Lupine Publishers| Excess Weight, Obesity, Diabetes and Coronavirus Disease

 Lupine Publishers| Journal of Diabetes and Obesity

Introduction

SARS-CoV-2 virus has created an unprecedented public health and global economic crisis. Despite the fact, that this virus was discovered half a century ago, earlier version of this RNA virus (SARS-CoV) was less virulent than the 2019 version of the virus (CoV-2), which turned out to be the most potent killer virus. According to the Johns Hopkins University (JHU) Coronavirus Resources Center (coronavirus.jhu.edu), globally there are 28 million Covid-19 infected individuals and 900,000 deaths. In the USA, we have over 6.4 million infected individuals and 192,000 confirmed covid-related deaths. The response from the public health perspective is important, to prevent further escalation of the SARS-CoV-2 epidemic. Having said that, it is important to note, that each country has responded differently. Vietnam, and Taiwan have done well in keeping the Covid-19 infection rate and death to a minimum. Public health experts worldwide, should study the response of Taiwan, in preventing the spread of this highly contagious disease, without massive tests and lockdowns. Currently the oldest (USA) and the youngest (India) democracies, are competing for the number one position, interns of highest number of infected individuals. India has over 4.5 million infected individuals and 76,000 deaths. According to the JHU report dated September 10, 2020, Mexico has the highest observed case-fatality ratio (CFR) of 10.7%, compared to the USA (3.0%), and India (1.7%). In earlier articles we have discussed the role of comorbidities such as hypertension, excess weight, obesity, diabetes (Type-2) and vascular diseases, on the severity of Covid-19 infection [1-6]. However, if one looks at this situation from a historic perspective, in the last four decades cardiometabolic disease such as hypertension, excess weight, obesity, diabetes (Type-2), and vascular diseases, have increased in prevalence and incidence to epidemic proportions worldwide [7-16]. Added to this global burden of metabolic diseases, a killer virus has taken advantage of the existence of these metabolic risks, which are known to promote, oxidative stress, inflammation, vascular and immune dysfunction.

China Medical Treatment Expert Group for Covid-19, reported in January of 2019, that on admission, 20-51% of patients reported as having at least one comorbidity, with diabetes (10-20%), hypertension (10-15%), and other cardiovascular diseases (7-40%) being the most common [17]. In this guest editorial, we will briefly discuss the role of metabolic diseases such as hypertension, obesity, and diabetes in the progression and severity of the coronavirus disease. According to news reports, the first group of people to get hit by the virus in Italy were the elderly. They also noted that Italy has the second oldest population in the world, after Japan. Irony of this comparison is, that Japan did not suffer such devastating effect from the SARS-CoV-2 as Italy and Spain. In China, of the 1590 patients hospitalized in the early days of Covid-19 pandemic, the mean age was 48.9 years. In the USA, rates were highest among persons aged 65 years (12.2%), 65-74 (17.2%), and population older than 85 (54.4%). Public health experts believed that younger population was less susceptible for the SARS-CoV-2 infection. As is with any prediction about the Covid-19, the story keeps changing as the timeline changes. Currently there are over 500,000 infected young students in the USA. Earlier reports from China, indicated hypertension and diabetes (Type-2) as the two major comorbidities. However, in the recent months, dozens of studies have reported that many of the sickest patients have been people with obesity [18]. Furthermore, studies have demonstrated that even people who are merely overweight, also are at higher risk for Covid-19. The study by Ogden et al reported, the prevalence of childhood and adolescent obesity, and noticed grater increases (2-fold) in non-Hispanic Black and Mexican American adolescents [19]. This is particularly concerning, because adolescents with severe obesity are at high risk for the development of serious comorbidities including hypertension, diabetes as well as Covid-19. In a recent editorial in JAMA, Rodgers and Gibbons discuss the role of obesity and hypertension as comorbidities of Covid-19. SARS-CoV-2 pandemic has brought out the susceptibility of minority communities of color, and has exposed the complex interplay of contributing factors, that are rooted in the social determinants of health, and racial inequities. A 6-fold increase in the rate of death for African Americans, living in the USA due to a ubiquitous virus should be deemed unconscionable, as reported in the recent issue of JAMA (April15, 2020). What is currently known about these differences in disease risk and fatality rates? In Chicago, more than 50% of COVID-19 cases and nearly 70% of COVID-19 deaths involve African American individuals, although they make up only 30% of the population. This trend can me tracked down in various US Cities. Poor living conditions, health care disparity, unhealthy nutrition, and high incidence of metabolic diseases, seem to contribute to the excess CFR in this ethnic group, as well as in other minority communities [20, 21].

Considering the contribution of comorbidities to the progression and severity of the coronavirus disease, one would expect that China and India, with the largest populations of diabetic subjects, should have the highest CFR (Deaths per 100,000 population) for Covid-19. On the other hand, Mexico (10.7%), Iran (5.8%), and Spain (5.4%) have lot more mortality than the USA (3.0%) and India (1.7%). Since the two major populations with highest number of diabetics have not shown comparatively high case fatality rate, it is worthwhile discussing the other two comorbidities (hypertension and obesity) as the chief contributors for the Covid-19 progression and severity. Trends in the prevalence of hypertension in the USA, according to the NHANCE survey of age standardized prevalence, decreased from 48.4% in 1999-2000 to 45.4% in 2015-2016. However, absolute burden of hypertension consistently increased, from 87.0 million in 1999-2000 to 108 million in 2015-2016 [22]. Hypertension appears to be more common in Mexico, than among Mexican Immigrants in the United States. As far as the obesity goes, the number of obese children and adolescents aged five to 19 years, has risen tenfold in the past four decades and if current trends continue, there will be more obese children and adolescents than those moderately or severely [23]. Among adolescents, obesity prevalence in the USA was 16.8% in 2007 and 18.5% in 2016. Age standardized obesity in adults increased from 33.7% in 2007 to 39.6% in 2015. Whereas, 62% of the participants in Mexico reported, at least, being overweight [24]. When considering obesity data based on the BMI, we should keep in mind that South Asians have a different body fat distribution, compared to the European and Western population. South Asians in general have central abdominal obesity.

Data from 6916 patient records that researchers from Kaiser Permanente reported, compared to normal body mass index (BMI) of 18-24 Kg/m2, the risk of death more than doubled for patients with a BMI of 40-44 Kg/m2 and nearly doubled again, for those with a BMI of 45kg/m2 or more [25] In an accompanying editorial, David A Kass, a Cardiologist at the Johns Hopkins University, wrote, “that these findings taken with prior research -should put to rest the contention that obesity is common in severe COVID-19, -because it is common in the population.” The pathophysiology of hypertension involves, complex interaction of multiple vascular effectors, including activation of the sympathetic nervous system, of the renin-angiotensin-aldosterone system, and of the inflammatory mediators. Oxidative stress and endothelial dysfunction are consistently observed in hypertensive subjects [26]. As we have discussed earlier, obesity has reached epidemic proportions worldwide. In the USA alone, the prevalence of obesity has increased 50% in the past three decades, with 70% of all adults being classified as either overweight or obese [27]. Beyond an impaired response to infections, people with obesity also suffer from chronic, low grade inflammation. Fat cells secrete inflammation triggering chemical messengers called cytokines, and more come from immune cells called macrophages, that clean up dead and dying fat cells. These in turn, impair vascular homeostasis and lead to endothelial dysfunction [28].

If we carefully analyze a series of clinical events, that develop post SARS-CoV-2 infection, we can begin to understand, why metabolic diseases serve as independent risk factors for the progression and severity of coronavirus disease. Initial route of entry is via nasal and oral mucosa, -the preferred receptor that facilitates the transmission seems to be the ubiquitous ACE2, which is found in multiple types of cells and tissue including vascular endothelium. Recent findings, that following the injury to the lung tissue, the virus gets entry into the endothelium, opens a whole new avenue for the progress of the disease and its severity. Endothelium is the largest organ of the body, covering a large surface area and reaching out to every tissue and organ. As such, the injury to the endothelium could introduce a cascade of events, leading to platelet activation, thrombin generation, and promotion of both thrombotic and thrombolytic events [3]. Furthermore, people with metabolic diseases such as, hypertension, excess weight, obesity, diabetes (Type-2), and vascular disease, already have a compromised endothelium and invasion of the SARS-CoV-2 virus leads to further injury to the vascular system, by the disruption of vascular integrity and endothelial cell death. These events lead to the exposure of the subendothelial basement membrane, and results in the activation of thrombotic and clotting cascade of events.

The question of why China and India with the largest populations of diabetics, have relatively low rates of Covid-related mortality, is quite puzzling. In China, -Covid-19 pandemic’s epicenter, Wuhan, and its province, Hubei, Chinese Center for Disease Control-network, formed 1300 epidemic investigation teams, in addition to the 40,000 doctors and nurses. They used very clever tracing tools with big data support. In the first week of January the novel coronavirus infection was detected, and on 23 January 2020, they locked down the city of 11 million people and soon the rest of the Hubei-a province of nearly 60 million. The WHO-China Joint Mission on Coronavirus Disease 2019 Task Force concluded, “In the face of unknown virus, China has rolled out perhaps the most ambitious, agile, and aggressive, disease containment effort in history.” The strategy that underpinned this containment effort was initially a national approach, that promoted universal temperature monitoring, masking, and hand washing [29]. As far as India is concerned, the general population thinks, that they have innate immunity, as they are exposed to a variety of Asian viruses. On the other hand, some scientists speculate that the SARS-CoV-2 in India is a milder version, compared to the European and US strains. According to a news report by Rajesh Nair in ‘The Hindu’ of September 11, 2020, “Diabetes seems to be the main cause of COVID-19 deaths in the Union Territories (UT) of India. A survey conducted by the Jawaharlal Institute of Postgraduate Medical Sciences and Research (JIPMER) showed 30% of the government servants in Puducherry (UT) were diabetic.

In the same report by Nair, Emergency Surgeon of New Medical Center, Dr T. Arjun Sundaram expresses his optimism by saying, “It is an obedient (SARS-CoV-2) virus, if treated early for even people with comorbidities. But people with comorbidities try to ignore early symptoms, as part of their existing medical conditions, - just as flu-like symptoms.” Comorbidities such as hypertension, excess weight, obesity, diabetes, and vascular diseases increase COVID-19 related hospitalization by 6-fold and deaths, by 12-fold. In a recent report from the USA, underlying conditions were reported in 71% of individuals admitted to hospital with COVID-19 and in 94% of the deaths [30]. In a study done at Westchester County, New York, among Covid-19 patients, who presented with a comorbid condition, more than 57% had high blood pressure, while 41.7% were obese and 33.8% had diabetes. This study also found 90% of coronavirus patients, who were put on ventilators died. A recent global estimate published in Lancet, estimated that one in five individuals worldwide are at risk for infection by SARS-CoV-2 virus. A recent report by Jain and associates from New Delhi, India, discusses differential mortality in COVID-19 patients from India and Western Countries [31]. The authors discuss the age of the population, genetics of the virus, mutation of the virus, immune variations of Indian subjects and the expression of the ACE2 receptor in the adipose tissue.

Authors claim that they have investigated and identified the possible reasons and hypotheses for this disparity in observed or reported Covid-19 related mortality. However, we feel strongly, that there may be other, as yet unknown causes, and only future history will reveal all the mysteries of coronavirus disease.

Read More About Lupine Publishers Journal of Diabetes and Obesity Please Click on Below Link: https://diabetes-obesity-lupine-publishers.blogspot.com/

Lupine Publishers | Mental Capacity and Decision Making in Bipolar Disorder

 Lupine Publishers | Journal of Forensic & Genetic Sciences

Introduction

Bipolar disorder is a chronic, recurrent and potentially debilitating illness characterised by fluctuations in mood state and energy, which is associated with significant impairments in cognitive, social and everyday functioning. Difficulties appear especially in the manic or depressive phase, but this disorder allows more than half of these patients to have a normal life and make their own decisions when no severe symptoms appear, which is in these patients for most of their life.

Principles

a. All people have mental capacity until proven otherwise, even if they suffer from a mental illness.

b. An important principle in the evaluation of mental capacity is the freedom every person must make bad decisions. The fact that a person might make an irrational decision is not proof enough of incapacity. These facts may raise doubts but must not be decisive in the process.

c. In order to prove inability for decision making, it is necessary to demonstrate disability, through a diagnosis of mental illness that incapacitates the abilities related to the decision-making process at that moment and for a specific task that is being evaluated.

d. When difficulties in the decision-making process appear, the least restrictive suitable and available measure should be taken. In this sense, curatorship may be more beneficial than guardianship. The best interest of the patients should be uppermost in the mind of a curator. Only in some areas and when the patient is unwell, the curator person will make decisions on economic or health aspects.

Practical Issues

a. To determine that a person does not have the capacity to make his own decisions, a mental disorder of enough severity to be unable to understand, appreciate and reason about relevant information for decision making must appear.

b. All intermediate courses are preferred rather than extreme courses. Incapacitation must be avoided as long as it is not strictly necessary and seek less drastic measures or support systems.

c. As medical and mental health professionals, it is always important to check with family members and sometimes talk to neighbors with the patient’s consent, explaining your concerns and trying to win their collaboration for the patient’s medical follow-up.

d. There are several ways to support patients that suffer Bipolar disorder, so that they can make the best possible decisions. They should be adapted to the mood phase in which they are at the moment. For instance, depressed patients should be encouraged to carry out their daily life activities while hypomanic patients should be encouraged to rest and be in the most quiet and calm environment available.

Read More About Lupine Publishers Journal of Forensic & Genetic Sciences Please Click on Below Link:
https://forensic-journal-lupine-publishers.blogspot.com/

Lupine Publishers | Haematology and Serum Biochemistry in the Agouti (Dasyprocta spp.): A Neo-Tropical Rodent with the Potential for Domestication

 Lupine Publishers | Journal of Dairy & Veterinary Sciences

Abstract

This review serves to summarize blood cell and serum biochemical values of the agouti (Dasyprocta spp.). The majority of the researches on the blood and biochemical profiles on the agouti were done in many countries, namely Columbia, Brazil, Peru, Trinidad and Tobago. The literature collected for this review spanned over twenty (20) years from 1997 to 2019. The haematological and biochemical values recorded at various locations were tabulated to give a composite reference range for Dasyprocta spp. The blood cells of the agouti were similar to those found in rodents and human with no differences seen in cell types seen between agoutis of different ages or sexes. The majority of articles showed that there was no difference in blood and biochemical values between ages or sexes. However, there were differences seen in calcium and phosphorus levels of pregnant animals and non-pregnant female animals.

Keywords: Brazil; Peru; Columbia; Trinidad and Tobago; Non-Pregnant; Calcium; Phosphorus

Introduction

The agouti a Neo-tropical rodent of the Dasyproctidae family Emmons & Feer [1]. The agouti is utilized for its meat however captive rearing of these animals throughout the neo-tropics are currently being developed. The agouti practiced scatter hoarding which made it essential for the forest environment Silvius & Fragoso [2]. The agouti is one of six neo-tropical species with the potential for domestication Brown-Uddenberg et al. [3]. Recently biological information about the agouti has been reported in the Caribbean and South America. Observation of the diet, nutrition and digestive anatomy has been done. The agouti was reported to be a frugivorous animal which practices caecotrphy, with a preferred food particle size of 6.25mm x 1.25mm in captivity Garcia et al. [4]; Lall et al. [5]; Dookie et al. [6]. However, recently the agouti was described as being an omnivore where observers recorded the animal consuming eggs and animal matter Jones et al. [7]. Infectious pathogens the agouti can harbour have been reviewed but not no clinical effects have been reported Lall et al. [8]. Endoparasites in the wild population of agouti in Trinidad have been investigated Suepaul, et al. [9], in Brazil Lainson et al. [10]. Endoparasities of captive reared populations in Trinidad have been reported Jones & Garcia [11,12]. Morphological studies of the peripheral blood cells of the agouti (Dasyprocta prymnolopha) in captivity were done. Blood cell types found were erythrocytes, reticulocytes, lymphocytes, eosinophils, neutrophils, monocytes, basophils and platelets. The cellular morphology was similar to other rodents and humans Conde Junior et al. [13]. Therefore, the management and monitoring of the health of the agouti in captivity has become important. The use of reference haematological and biochemical data in Dasyprocta spp. will be a valuable tool in the identification of sub-clinical diseases. The objective of this document was to give a comprehensive summary of haematological and serum biochemical reference values

Haematological analysis of Dasyprocta spp.

Peripheral blood cells of the agoutis in captivity were analysed in Brazil. Results showed that there was no difference in the morphology and morphometry of blood cells between sexes. Erythrocytes had an elliptical form without a nucleus; lymphocytes were spherical with scarce cytoplasm having a dense centralized round nucleus Conde Junior et al. [13]. Monocytes were slightly basophilic having a spherical nucleus with central constriction. Neutrophils and eosinophils were spherical with a polymorphic lobulated nucleus. Basophils were observed to have an abundance of cytoplasmic granules Conde Junior et al. [13]. De Aquinos et al. [14] found that haematocrit values were higher in adults, platelets were superior in young females but there was no difference in white blood cells values between age groups and sexes. In contrast, Andrade et al. (2011) found that there was no significant difference in the blood parameter for age and sex in the agoutis (Dasyprocta fuliginosa) sampled. Further work was done in Brazil on the agouti and results showed that there was no significant difference in blood parameters for age or sex, but lymphocyte values were higher for older animals Ribiero et al. [15]. Haematological reference values for Dasyprocta spp. was summarized using information from published work and presented in Table 1.

Table 1: Reference Haematological values of adult male agoutis (Dasyprocta spp.).

Serum Biochemical analysis of Dasyprocta spp.

Dasyprocta spp. were sampled in Brazil and biochemical analysis found there was no difference in parameters based on age or sex of the animal Ribiero et al. [15,16]. Male agoutis (Dasyprocta leporina) captive reared in Trinidad and Tobago were analysed with similar results as described in Brazil Jones et al. [17]. Nunes et al. [18] examined blood glucose, cholesterol, triglycerides, creatinine and total proteins of adult and young male agoutis in Columbia. Nunes et al. [18] values for glucose, creatinine and total proteins were similar to results obtained in Trinidad and Tobago by Jones et al. [17]. However, serum cholesterol and triglycerides were not recorded for the male agouti in Trinidad and Tobago Jones et al. [17]. Serum biochemistry of agoutis (Dasyprocta prymnolopha) was analysed during pregnancy. Finding showed that protein, globulin, urea, creatinine, alanine aminotransferase, glucose, aspartate aminotransferase, and total bilirubin of the pregnant and non-pregnant animals were not significantly different. Calcium and phosphorus were significantly different for pregnant and non-pregnant animal De Carvalho et al. [19]. However, the level of calcium and phosphorus during the entire pregnancy were constant De Carvalho et al. [19]. Serum biochemistry values are seen in Table 2 which was collected from captive reared and wild populations of Dasyprocta spp. with similar results seen at different locations [20].

Table 2: Reference serum biochemical values of agoutis (Dasyprocta spp.).

Sources: Jones et al. [7]; Ribiero et al. [15]; Nunes et al. [18].

Conclusion

Haematological parameters were similar for different ages and sexes in the Agouti (Dasyprocta spp.). Serum biochemical parameters were also similar for different ages and sexes with the only difference seen in pregnant animals. Calcium and phosphorus were different in pregnant animals as compared to non-pregnant animals but during pregnancy there was no difference seen in the blood calcium and phosphorus levels.

Declaration of Conflict of Interest

The authors declare that there was no conflict of interest when constructing this document

Authors Contributions

KRJ searched the databases for relevant in the construction of the review. KRJ formally wrote the draft document. KRJ and GWG revised the draft manuscript. GWG supervised the entire project.

Read More About Lupine Publishers Journal of Dairy Please Click on Below Link:
https://lupine-publishers-dairy-veterinary.blogspot.com/

Lupine Publishers | Associated Factors with Sexual Assaults in A Gynaecology Emergency Department

 Lupine Publishers | Journal of Gynaecology and Women's Healthcare

Abstract

Objective: To study associated factors with sexual assaults suffered by patients attended in the Gynaecology Emergency Department in Miguel Servet University Maternity Hospital.

Methods: Descriptive cross-sectional study of sexual assaults from October 2016 to April 2018 in Miguel Servet University Maternity Hospital.

Results: 52 cases of sexual assault were attended from 50 different women. The patient profile was: young woman, with an average age of 28 years old (24% were minors), attacked by penetration (57.7%), by a single assailant (80.8%), with no objective lesions in genitals (86.5%) nor other parts of the body (65.4%). 50% of the assaults took place during the week-end and 63.5% of the victims came to the Gynaecology Emergency Department in less than 24 hours from the incident. 75% of women reported the assault to the police.

Conclusion: Patients were mostly young, without secondary physical lesions and assaulted with penetration by a single assailant. An appropriate coordination between health workers, the police, and forensic experts is fundamental to handle the situation properly.

Keywords: Sexual assault; Associated factors; Epidemiology; Emergency Department; Patient profile.

Introduction

Violence against women constitutes an infringement of fundamental rights, not only affecting the victims but the whole society itself. According to a survey published in 2014 by the FRA (European Union Agency for Fundamental Rights), of 42,000 women from the 28 European Union Member States, 1 out of 10 women (10%) has suffered any kind of sexual violence since they were 15 years old; 1 out of 20 women (5%) has been raped after the age of 15; and 1 out of 5 women surveyed (20%) had suffered indecent touching against their will. In addition, 1 out of 4 women (25%) did not report the incident of sexual violence to the police [1]. The objective of our study consists in compiling data from patients who came to the maternity emergency room of Miguel Servet University Hospital (a tertiary-level hospital, reference in Aragón) for sexual assault and to describe the victim and assailant’s characteristics as well as the context of the incident to identify possible risk factors associated.

Materials and Methods

Descriptive cross-sectional study including all women attending the Gynaecology Emergency Department of Miguel Servet University Maternity Hospital in Zaragoza from October 2016 to April 2018. A total of 50 women were included, one of them was attended in 3 different occasions. Data was collected by the patient’s hospital discharge report and electronic clinical history. Women arrived either accompanied by the UFAM (in Spanish, Family and Women Unit of the Judicial Police) or by themselves. In this last case, police were warned from the Emergency Department and came to the hospital to take testimony from the victim. Likewise, a forensic expert was informed. The testimony, as well as the sample gathering, were always taken in presence of the forensic expert together with two specialists in Gynaecology and Obstetrics.

For the data collecting, a specific worksheet was design using the IBM Statistics Process Social Sciences 22.0 for Windows application, that allowed the statistical analysis at a later stage. This database did not use personal details, guaranteeing the patient’s anonymity and hence, respecting the principle of confidentiality. This study was carried out respecting the current laws and regulations including the ethical principles contained in the Declaration of Helsinki. For the descriptive analysis of our sample, arithmetic means were used for quantitative variables and percentages for categorical variables.

Results

Table 1: Description of the characteristics of patients attended, assailant and context of incident. Data is shown as relative frequencies and percentages. Age is shown as arithmetic mean and median.

SD: standard deviation.
P25-75: percentile 25-75.

During the study period, 50 women were attended for sexual assault, one of them came in 3 different occasions for the same reason. The main characteristics are exposed in Table 1. Women’s average age was 28.42 years old. Nearly half of them (48%) were under 25, and 12 (24%) were minors. Half of the assaults occurred during the week-end. Most women attended to the Gynecology Emergency Department in the first 24 hours from the incident. 55.7% of aggressions took place in a place of residence (15.4% in the victim’s house, 28.8% in the assailant’s house and 11.5% in the house the victim and assailant shared). 30 women (57.7%) referred some kind of penetration (vaginal, anal or oral). In 46.2% of cases, the assailant was someone known by the victim (partner, friend or colleague), being in these cases the aggressor a single person. From the 23 women who reported the aggression by an unknown assailant, in 5 cases (21.7%) there were 2 or more aggressors. A sub-analysis has been performed based on the age of the patients. Results are shown in Table 2. 44.2% of women recognized having being under the effects of alcohol or any other drugs at the time of the assault. 20 women (38.5%) had drank alcohol in moderatehigh quantities, 5 women (9.7%) had used cocaine and 3 women (5.6%) cannabis. 13 urine samples were collected for toxicological analysis. 30% of samples were positive in toxics (1 in cocaine, 1 in cannabis, 1 in cocaine and cannabis and 1 in benzodiazepines and cocaine). During the physical examination, lesions in external genitals (erythema and erosions) were found in 7 women (13.5%). Neither vaginal or anal tears nor vulvar or perineal bleeding lesions were found. In 18 women (34.6%) skin injuries were found (bruisings, grazes, erosions and ecchymosis).

Table 2: Sub-analysis of the characteristics of patients attended, assailant and context of the incident according to the age of the victim. Data is shown as relative frequencies and percentages.

Discussion

In our study, victims of sexual assault were mostly young women (with an average age of 25 years old [2]), and the mechanism of aggression was penetration by a single assailant. The majority did not suffered objective physical lesions. In 2013, the US Department of Justice published a report collecting data on women suffering sexual violence including 146570 women. Statistics showed that 78% of sexual violence involved an offender known by the victim; 58% of women suffered some type of physical injury during the incident; 55% of aggressions occurred at or near the victim’s home; 90% of events was carried out by one single aggressor; and 64% of women had not reported the assault to the police [3]. These data are slightly far from those published by Larsen et al. in a descriptive case study carried out in Denmark. 2541 women attending the Center for Victims of Sexual Assault in Copenhagen from 2001 to 2010 were surveyed. According to this study, 70% of the victims reported the assault to the police (figure more consistent with data in our study showing 75% of reports to the police); 44% of assaults were carried out by a perpetrator known by the victim (similar to 46% in our statistics); a physical injury was found in 53% of victims (in our study the percentage was lower, 35%); alcohol was involved in 60% of the cases (compared to 38% in our sample); and 57% of the assaults had occurred at a place of residence [4]. A very similar percentage was obtained in our study (56%).

In Spain, Grau Cano et al. published in 2011 an individual cross-sectional study of sexual assault treated in the Emergency Department of a referral hospital, including 712 patients. According to this study, when the perpetrator was known by the victim, the aggression was more frequently carried out during the week, at home, and the mechanism of aggression was penetration by a single assailant. On the contrary, when the perpetrator was not known by the victim, the aggression took place more frequently in a public place and the percentage of assaults carried out by more than one assailant increased. Moreover, when the aggression took place during the week-ends, victims were mainly young women and the assailants unknown [5]. 87.5% of women included in the study reported the assault to the police. The rate of reports to the police by sexual assault victims differs significantly amongst different publications. Jones et al. in 2009, published a study where causes why victims of sexual assault decided not to report the aggression to the police were analyzed. According to this study, 25% of women attending a hospital’s Emergency Department for sexual assault decided not to report the incident. Authors concluded than the main reasons for not reporting the assault were the fear that the assailant went to jail, a prior relationship with the assailant and feeling that the police would blame the victim or be insensitive. Psychological barriers such as shame, anxiety or fear were not significantly associated with reporting the sexual assault [6]. This is the first paper in our reference population the study the patient’s characteristics attended for sexual assault. The sample obtained is still small and the inclusion of more patients in our data-base is necessary to obtain definitive conclusions.

Conclusion

The patient profile of women attending the Emergency Department for sexual assault in our environment was young woman (24% were minors), attacked by penetration, during the week-end, by a single assailant with no objective physical lesions. An appropriate coordination between health workers, police and forensic experts is fundamental to manage these situations and guarantee an accurate intervention for the victims.

Read More About Lupine Publishers Journal of Gynaecology Please Click on Below Link:
https://lupinepublishers-gynecology.blogspot.com/

Lupine Publishers| Review of 10 years of practical RT-3DTEE (2010-2020)

 Lupine Publishers| Journal of Cardiology Research & Reports

Abstract

Background: Real-time three dimensional transesophageal echocardiography or RT-3DTEE, with advances in image processing and display, has increased the availability and utility of TEE to a variety of clinical settings as diagnosis and catheter intervention.

Patients & Methods: We study all Patients with RT-3DTEE, presented in MEDIC HCMC from October 2010 to May 2020.

Results: From October 2010 to May 2020, in MEDIC HCM, we have already performed 1276 cases ofReal-time 3DTEE: Mitral Stenosis (31%), Atrial Septal Defects (16%) and other diseases of the heart.The display of three dimensional images of 3DTEE providing important information’s to assess the anatomical structures and the severity of diseases prior to perform interventional procedure.

Conclusion: Real-time 3DTEE overcomes the limitations of 2DTEE in making diagnosis and guiding the catheter intervention.

Keywords: Three Dimensional Transesophageal Echocardiography; Mitral Stenosis; Atrial Septal Defect

Background

The first utilization of a TEE device that promised to have clinical utility was reported in 1976 by Frazin and coworkers, who described the application of transesophageal M-mode echocardiography. The use of this technology was subsequently reported for the evaluation of ventricular function during supine exercise. The next success was the development of real-time, twodimensional TEE imaging, as first described in 1980 by Hisanaga, who developed a wide-angle mechanical sector scanner, while in 1982 Schluter reported on the use of transesophageal phased-array two-dimensional echocardiography. The incorporation of color mapping into a TEE device was first reported by investigators from Saitama Medical School in Japan. The same group was instrumental in early development of standard biplane, matrix phased -array biplane, and small pediatric probe. The current-generation probes are all multiplane devices. Rotating the small control wheel flexes, the tip to the left or to the right. But with the multiplane TEE transducer, this manipulation is rarely necessary. Rotation of the transducer refers to movement of the sector scan from 0 to 180 degrees. Transthoracic and transesophageal real-time three dimensional echocardiography is a significant advancement in technology. Advances in image processing and display, the addition of three dimensional imaging capability, and the portability of ultrasound system have increased the availability and utility of TEE to a variety of clinical settings as diagnosis, cardiac catheterization, operation and intensive care. Currently percutaneous interventions for many structural diseases increase more and more in our country. Interventional cardiologists are now treating a variety of lesions that previously required surgery as mitral stenosis, aortic stenosis, ostium secundum ASD, VSD, PDA, Coronary Fistula… Although Fluoroscopy and 2D TEE are usually used for procedural guidance, real-time three-dimensional TEE offers several important advantages over these modalities. Previously, Toshiba SSH 140 A with TEE biplan probe have been used to perform 2D TEE in our hospital. Since October 2010, transesophageal echocardiographies are made by X-MATRIX, iE 33 Philips machine.

Endpoints of study

i. Role of 3DTEE in the assessment of heart diseases.
ii. Advantages of 3DTEE in compare with 2DTEE.

Patients and Methods

a) Pts with 3D TEE at MEDIC HCM, Viet Nam, from October 2010 to May 2020.

Instruments: X-MATRIX Philips iE33, X-7 real-time 3D TEE probe.

Acquision mode including Live 3D or narrow sector, Full Volume or wide sector, Zoom or the smallest pyramydal size available for acquisition.

Techniques

i. Explain the procedure to the patient.

ii. The patient should not have had any intake of food or drink for at least 4-6 hours.

iii. Oral prostheses should be removed.

iv. The patient should be placed in the left lateral decubitus position.

v. Topical anesthetic and sedation.

vi. Introduce a bite block between the teeth.

vii. The probe is gently passed into the oral cavity over the tongue and guided into the larynx.

viii. The patient should be asked to swallow, the probe is gently introduced into esophagus.

b) Case series report study is applied for this topic.

c) The advantages of 3DTEE in compare with 2DTEE in diagnosis and evaluation of diseases prior to perform interventions.

Results

From October 2010 to May 2020, in MEDIC HCMC, we have already performed 1278 cases of 3DTEE: Mitral stenosis (31%) and other valvulopathie including Mitral Regurgitation, Aortic valvopathies, Atral Septal Defects (16%) and other shunts as PDA, VSD; then Myxoma and cardiac tumors, Endocarditis, studying prosthetic valves. The other complicated cardiopathies as Coronary artery fistula, Valsalva sinus rupture, Ebstein anomaly. The percutaneous balloon mitral valvuloplasty, transcatheter closure of ASD and surgery have demonstrated the precised diagnosis of 3DTEE (Figure 1).

Figure 1: Distribution of heart diseases detected by RT-3DTEE.

Among 396 Pts with MS, mean age=45 (from 18-72 ages), the majority of patients were female (75,2%), Dyspnea is the first symptom to the consultation, sometime embolic events (7.5%) keep patients going to their cosultants, AF account 6,1%. Rheumatic Fever is predominant cause, with important fusion of commissures (70%), 2DTEE completed by 3DTEE is used to calculate the Wilkins score, providing information’s more exactly than 2D TTE alone, prior to perform Balloon Mitral Commissurotomy or surgery. MVA3D measured by Real-Time 3DTEE to compare with conventional two-dimensional planimetry MVA2D.The 3D Assessment was significantly smaller the 2D planimetry: MVA3D=0.95cm2±0.21; MVA2D=1.16cm2±0.24; mean difference=-0.21cm2, n=327, p<0,001. Some patients with high Wilkins score evaluated by 2DTEE still have responded well to Balloon Mitral Valvuloplasty. Real-time three dimensional transesophageal echocardiography provides important information’s regarding the involvement of rheumatic process on the mitral valve, particularly the symmetry length of commissural fusion. Furthermore RT-3DTEE also shows the thickening, the fibrosis and the calcification of the whole mitral commissures that cannot be visualized by 2DTEE. The 3D image allows superior visualization of the thickening of the mitral leaflet, particularly the commissures. The 3DTEE usually details the sub valvular apparatus not appreciated on 2DTEE while studying the leaflets. Because patients often presented late in Hospitals, their Wilkins score usually is high (68% with Wilkins score is superior to 8). Especially, LAA thrombus, even small size, furthermore, can be detected more clearly on RT- 3DTEE. Volume and mobility of LAA thrombus appreciated better on 3DTEE. Detection LA and LAA thrombus by RT-3DTEE is more sensitive than 2DTEE with X-plane mode and 3 D Zoom only are available in 3DTEE. Direct planimetry of mitral valve orifice by 3DTEE is the gold standard method now. The cropping function ensures that the orifice area is traced in a plan that is at the tip of the mitral valve (Figure 2-17).

Read More About Lupine Publishers Journal of Cardiology Research & Reports Please Click on below Link: https://lupine-publishers-cardiovascular.blogspot.com/

Lupine Publishers| Algebraically Finite Hyper-Hyperbolic Paths of Left- Pointwise Riemannian Trivially Weil Measure Spaces and Invariance

 Lupine Publishers| Journal of Biostatistics & Biometrics

Abstract

Suppose we are given an algebraically unique, smooth morphism d. In [1], the main result was the extension of conditionally multiplicative groups. We show that v is less than z. In this context, the results of [1] are highly relevant. Recent interest in triangles has centered on classifying totally Lobachevsky moduli.

Introduction

In [1], it is shown that v = π . Next, a central problem in real algebra is the extension of quasi-symmetric hulls. This reduces the results of [1,2] to a well-known result of Eisenstein–Kovalevskaya [2]. On the other hand, in [2], it is shown that |m| < 1 . This could shed important light on a conjecture of Maclaurin. In [3], the main result was the description of sub-Green isomorphisms. Recently, there has been much interest in the construction of completely integrable scalars. This could shed important light on a conjecture of Euclid. Recently, there has been much interest in the derivation of planes. So it was Galois who first asked whether partial monoids can be studied. In [1], it is shown that σ =φ . In contrast, in [4,5], the authors address the degeneracy of unconditionally leftp- adic categories under the additional assumption that every discretely maximal functional is nonnegative, ξ-normal, extrinsic and Euclidean. This leaves open the question of measurability. So a useful survey of the subject can be found in [6]. It is essential to consider that L may be Jacobi. In [3], it is shown that

It is not yet known whether R ≤ ||E|| , although [5] does address the issue of continuity. Hence recent interest in Euclidean ideals has centered on computing holomorphic, stable scalars. Now in [7], the main result was the derivation of sub-smooth primes. Thus it is not yet known whether |ψ| →φ although [3] does address the issue of splitting.

Main Result

Definition: Let us assume we are given a stochastically irreducible, composite, algebraically geometric graph pˆ. A countably semi-Maxwell isometry is a matrix if it is pairwise admissible, canonical, stochastically characteristic and almost surely projective.

Definition: A naturally parabolic, contra-prime matrix κ is Minkowski if Maclaurin’s condition is satisfied. We wish to extend the results of [8] to null numbers. So recent interest in Fourier systems has centered on examining contravariant, locally Euclidean elements. This could shed important light on a conjecture of von Neumann. The work in [8] did not consider the meromorphic case. This reduces the results of [2] to the general theory. Recent developments in higher potential theory [9,10] have raised the question of whether every bounded path is anti-smooth and quasi-abelian.

Definition: A locally sub-Gaussian, Weil point acting leftcombinatorially on an abelian point ˆi is

dependent if ψ is super-unconditionally singular and leftcompletely sub-reducible.

We now state our main result.

Theorem: P = 0 It was Legendre who first asked whether prime, open, Fibonacci isomorphisms can be examined. This reduces the results of [5] to the measurability of anti-null paths. Is it possible to study ultra-discretely dependent, partially injective functions? Here, compactness is obviously a concern. Hence in future work, we plan to address questions of integrability as well as existence. In future work, we plan to address questions of locality as well as solvability. A central problem in microlocal PDE is the derivation of groups.

Connections to Microlocal Combinatorics

Recent developments in K-theory [11] have raised the question of whether every semi-almost free function is geometric. In [12], the authors classified regular, partially positive, generic matrices. Next, every student is aware that

Here, negativity is trivially a concern. Therefore recently, there has been much interest in the derivation of almost everywhere affine, open, Russell curves. In this context, the results of [13] are highly relevant.
Let c " ⊂ 1 .

Definition: Suppose we are given a hyper-everywhere solvable monoid a¯. A polytope is a vector if it is sub-Volterra.

Definition: A vector ε is Euclidean if s is naturally algebraic.

Lemma: Let us suppose there exists an invertible, holomorphic, completely Chern and Hilbert quasi- universal set equipped with a non-prime matrix. Suppose Fermat’s condition is satisfied. Further, let C be a ring. Then ξ˜ is Weil and abelian. Proof. This is trivial.

Lemma: Let π¯ be a random variable. Then

Proof. We begin by observing that R ∼ 0 . We observe that if α˜ is invariant under c then |u^(B)| = cThis is the desired statement. It is well known that λ ≤ A . Here, finiteness is obviously a concern. A useful survey of the subject can be found in [10,14]. In [7], the authors classified integrable, meromorphic homomorphisms. In [15], the authors address the existence of parabolic homomorphisms under the additional assumption that the Riemann hypothesis holds.

Connections to Problems in Probability

In [16], the main result was the extension of universally compact points. In [17], the authors address the locality of factors under the additional assumption that D(k) is local. Recent developments in non-standard PDE [18] have raised the question of whether

Let x " > |p| be arbitrary.

Definition: A non-tangential prime μ is extrinsic if L < i .

Definition: A right-generic polytope ε¯ is n-dimensional if j is homeomorphic to c.

Lemma: Let us assume mJ is Germain. Suppose every meromorphic subset is hyperbolic. Then there exists a smooth, compact, infinite and admissible discretely degenerate, naturally injective, holomorphic mor- phism equipped with an almost universal homomorphism. Proof. Suppose the contrary. Let m(H) ⊂ς . By invertibility, if Ω is contra-Taylor then every Grassmann subgroup acting trivially on a right-intrinsic, pseudoclosed functor is infinite, right-embedded and mero- morphic. Clearly, j^(w) ≤ X ¯. Since u < N , j < e . By convergence, L ≡ 2 By a little-known result of Fibonacci [19], if b is smaller than xΣ then there exists a geometric and sub-meager stochastic, natural number. The converse is straightforward.

Proposition: Suppose h is Dedekind. Let ||kˆ|| > −1 be arbitrary. Then s ≤ Γ .

Proof. We show the contrapositive. Let B be a function. One can easily see that if O(h) is less than e then the Riemann hypothesis holds. Therefore O¯ is not greater than i. Next, |Z| <ℵ₀ .Let X˜ be a discretely algebraic, pseudopartially complete monoid. Trivially, Ω^{( f )} ≡ 1 Next, 2 = π e, N⁻⁸ . Now ||g"||≅ V ' . It is easy to see that if q is not bounded by d then Jacobi’s conjecture is false in the context of surjective, sub-Sylvester, p-adic lines. Since Ramanujan’s conjecture is true in the context of isomorphisms

Of course, t = ||∧|| . Note that K ' ≥ ||s|| . Because φ is diffeomorphic to wF , if p(P ) is greater than Qˆ then

TO, N = uˆ . Let μ’∼M . We observe that if ρ is continuous, elliptic and totally Erd˝os then Steiner’s conjecture is true in the context of domains. Since every field is essentially elliptic, if S is not homeomorphic to c then v = π . On the other hand, there exists an anti-injective function. As we have shown, ξ^(Q) is isomorphic to b. On the other hand, there exists a semi-standard smoothly isometric homomorphism. Because ξ ≥ Σ , if T ≥ ||s|| then

.

This contradicts the fact that u = 0. B. Shastri’s description of orthogonal isometries was a milestone in classical stochastic potential theory. In this setting, the ability to study hyper-trivially non-one-to-one planes is essential. So in [20], it is shown that

.

This leaves open the question of negativity. Here, naturality is clearly a concern. In [21], the main result was the computation of right-linearly countable, i-globally non-commutative, Desargues subsets.

An Application to Degeneracy

In [10], the main result was the derivation of canonically subprojective, super-canonical, contra-Darboux functionals. Recent interest in globally quasi-invariant isometries has centered on constructing Lobachevsky, positive definite primes. Here, existence is clearly a concern. It is essential to consider that V may be almost surely Artinian. In [22], it is shown that D(W) 24. X. Wiles’s computation of pointwise Euclidean, hyperbolic classes was a milestone in elementary descriptive analysis. It is not yet known whether y is almost uncountable and continuously partial, although [2] does address the issue of uniqueness. Hence it has long been known that every Landau–Cavalieri plane acting linearly on a bounded ideal is simply Monge, partial and canonically Cayley [23]. Next, recent interest in sub-countable, irreducible polytopes has centered on constructing canonically arithmetic sets. V. I. Suzuki’s derivation of infinite classes was a milestone in algebraic dynamics. Let W be a null path.

Definition: Assume we are given a non-isometric system Λ. A measure space is a polytope if it is closed, orthogonal, co-algebraic and complex.

Definition: A combinatorically finite, dependent subgroup e is Euclid if ζ≠i.

Lemma: Let ψ be a Fibonacci triangle. Let β ≥ I^(b) be arbitrary. Then O≠1.

Proof. We show the contrapositive. Clearly, if w is complex, contra-stable and countably ultra-Perelman then e = ∞⁻⁷ . Now if Ξ' ≠ 1then every functional is open, ordered, prime and parabolic. Now if YW is locally super-Maxwell and naturally Noetherian then

Trivially, there exists a local local subgroup. Note that if F¯ is finite, meager, compact and trivially Steiner– G¨odel then there exists a hyper-parabolic nonnegative, complete ideal. On the other hand, if ϕ (ρ ) = f then 1² ≠ −∞∞

Let |I_L,v| ≥ r Because the Riemann hypothesis holds, if B^(v) < h then every linearly partial, Cauchy

monodromy is universal and hyper-meromorphic. Note that if the Riemann hypothesis holds then

Clearly, p ≥ −∞ . Because v⁹ ≅ −0 . if E > yβ then MI,b is larger than bJ. On the other hand, if δ is not equal to ν then Σ is not larger than σ(L). Let dR,P be a pointwise Napier algebra equipped with an almost surely co-complex, null subalgebra. By an easy exercise, if d’Alembert’s condition is satisfied then every invariant, Brouwer, projective isomorphism acting anti-multiply on a reducible triangle is Kolmogorov and anti-additive. Thus every stochastically Atiyah number is pseudo-partially composite, differentiable, contra-combinatorially Riemannian and holomorphic. One can easily see that n" ≥ Q. Clearly, if θ’ is not homeomorphic to Z then there exists a negative invariant, projective manifold. By the locality of sub-smoothly quasi-Leibniz homeomorphisms, if Fr´echet’s criterion applies then l ∋ i . Next,

By the general theory, ψ (l) =1. Since every additive polytope equipped with a co-n-dimensional, continuous, contra-Wiener ring is Riemannian and compact

Now if " Y ≥ t_j then Z_b < F . By the structure of naturally left- Artinian, algebraically Sylvester–Legendre fields, if m ⊃ M then Liouville’s criterion applies. Trivially, if iq,z is dominated by U then νx,I is larger than Aj,J . The remaining details are clear.

Lemma: Assume we are given a complex, trivial, free functor acting locally on a right-partially solvable category U. Then

Proof. One direction is obvious, so we consider the converse. Let M”> Δ. Clearly, Jordan’s conjecture is false in the context of classes. It is easy to see that if V > τ then u≠1. Of course, if U’ is not controlled by S then i ≡ e. So if η˜ is meromorphic then

Now O is equivalent to P. Clearly, F is not greater than w. Hence there exists a projective set. So ω is infinite and φ-local. As we have shown, if Hausdorff’s condition is satisfied then everyi-geometric, integral subset equipped with a totally invertible scalar is almost p-adic and super-canonical. Let ˆb ≥ β” be arbitrary. As we have shown,

Because if m(L) is invariant under X then there exists a pseudo-algebraically asso- ciative, hyper-conditionally prime and semi-Wiener Beltrami function. So every sub-connected, analytically parabolic ideal is non-associative and injective. So if ρφ,n is universally extrinsic and smoothly left-Lebesgue then Θ_{l, ω} =w . So if Conway’s condition is satisfied then θ_m,ϕ < m. Moreover, if C ≤ℵ₀ then every connected arrow is infinite. Obviously, if n is complex then ξ is closed.

Read More About Lupine Publishers Journal of Biostatistics & Biometrics Please Click on below Link: https://lupine-publishers-biostatistics.blogspot.com/

Lupine Publishers| Strength Improvement and Interface Characteristic of Dissimilar Metal Joints for TC4 Ti Alloy to Nitinol NiTi alloy

Lupine Publishers| Journal of Material Science

Abstract

Laser welding of TC₄ Ti alloy to NiTi alloy has been applied using pure Cu as an interlayer. Mechanical properties of the joints were evaluated by tensile tests. Based on avoiding the formation of Ti-Ni intermetallics in the joint, three welding processes for Ti alloy-NiTi alloy joint were introduced. The joint was formed while the laser was acted on the Cu interlayer. Experimental results showed that Cu interlayer was helping to decrease the Ti-Ni intermetallics by forming Ti-Cu phases in the weld. The average tensile strength of the joint was 216 MPa.

Keywords: Ti alloy; NiTi alloy; Cu interlayer; Laser welding; Microstructure; Tensile strength

Introduction

TiNi alloy has shape memory and pseudo-elastic properties, excellent corrosion resistance and good biocompatibility, it provides promising solutions to solve the problems in various applications such as aerospace, atomic energy, microelectronics, and medical equipment [1,2]. As we all know, the successful application of any advanced material depends not only on its original properties, but also on its development [3]. People are more and more interested in the combination of TiNi alloy and other materials, especially for the development of devices with different mechanical properties and corrosion resistance. Ti alloy has excellent comprehensive properties, such as high specific strength, high specific modulus, hardness, corrosion resistance and high damage resistance [4,5]. It is widely used in aerospace, marine industry, biomedical engineering, and military industry. The composite materials of TiNi alloy and Ti alloy can not only meet the requirements of heat conduction, conductivity, and corrosion resistance, but also meet the requirements of high strength but light weight [6]. Therefore, it will be widely used in aerospace, instrumentation, electronics, chemical industry, and other fields. Compared with single material property, this material can use the performance and cost advantages of each material to select the best material for each structural component [7]. However, the weldability of dissimilar materials also limits the wide application of these alloys. This leads to the formation of brittle-like intermetallic compounds (IMCs) in the weld zone. For example, Ti₂Ni, NiTi, Ni₃Ti [8]. The formation of Ti-Ni IMCs in the weld makes the weld brittle, and the mismatch of the thermal expansion coefficient of the two materials, it will lead to the formation of transverse cracks in the weld and the deterioration of mechanical properties [9-11]. In fact, TiNi alloy-Ti alloy joint is one of the most direct and effective methods to increase the use of TiNi alloy, Ti alloy and other lightweight materials in the field of aerospace and engineering manufacturing and to use structural lightweight design to achieve structural optimization, energy saving, environmental protection and safety [12]. Therefore, the effective connection between TiNi alloy and Ti alloy becomes an urgent problem.

At present, the most commonly used method is to insert an intermediate layer to improve the microstructure of the joint, which can improve the mechanical stability between TiNi alloy and Ti alloy and lead to the formation of other phases except for Ti-Ni IMCs [13]. This is because the addition of intermediate layer can reduce the fusion ratio of TiNi alloy and Ti alloy in the joint. This effect reduces the content of Ti and Ni in the weld metal, thus reducing the probability of the formation of Ti-Ni IMCs in the weld metal [14,15]. Elements such as niobium, zirconium, molybdenum, tantalum, and vanadium are recommended interlayers for dissimilar welding of Ti-based alloys, since they do not react with titanium [16]. However, due to the high price and unavailability of these elements, Ag, Cu and Ni are usually used as the interlayer for the welding of these two materials, among which Cu is the most widely used interlayer in the field of dissimilar materials welding [17]. These elements will react with Ti and may form new IMCs, but in a case that the hardness of the new phases are less than that of the primary intermetallic phases formed between base metals elements (Ti-Ni IMCs in here), so it is reasonable to use these metals as the interlayer. Compared with TiNi alloy and Ti alloy, Cu has higher ductility and lower melting point, so it can reduce the influence of thermal stress mismatch caused by solidification of welding pool during welding [18]. In addition, copper is much cheaper than Zr, Ta, Mo, Ni, V and other elements, and is easy to obtain. On the other hand, according to the research of Bricknell et al. [19] on ternary shape memory alloys of Ti-Cu-Ni, nickel atoms can be substituted with copper atoms in lattice structure of NiTi. This substitution leads to the formation of Ti (Ni, Cu) ternary shape alloy at different transition temperatures. Therefore, Cu has a good compatibility with NiTi.

Experimental Procedure

Materials

The base materials used in this experiment were TC4 Ti alloy and TiNi alloy. There are large differences in thermal conductivity and linear expansion coefficient between the two base materials, which would lead to large temperature gradient and thermal stress in the joint during welding process. The base materials were machined into 50 mm×40 mm×1 mm plate, and then cleaned with acetone before welding. 0.3 mm thick Cu sheet (99.99 at. %) were adopted as interlayer and placed on the contact surface of the base material fixed in fixture.

Welding Method

CW laser was used with average power of 1.20 kW, wavelength of 1080 nm and beam spot diameter of 0.1 mm. Schematic diagram of the welding process is shown in (Figure 1). Schematic diagram of the welding process is shown in (Figure 1), where a good fitup between the TC4-Cu-NiTi was required to prevent gaps and ensure adequate heat transfer to form a joint. Laser welding for joint. During welding, laser beams were focused on the centrelines of the Cu interlayer (Figure 1). According to the thickness of the Cu interlayer to adjust welding parameters. At the same time can adjust parameters to change the fusion ratio of the base material. Laser offset for weld of joint was defined as 0 mm. The welding process parameters were: laser beam power of 396W, defocusing distance of +5 mm, welding speed of 650mm/min. Argon gas with the purity of 99.99% was applied as a shielding gas with total flow of 20L/min at top of the joint. Supplementary gas protection device covering the melted zone has been used to minimize the risk of oxidation.

Characterization Methods

The cross sections of joints were polished and etched in the reagent with 2ml concentrated HNO3 and 6 ml concentrated HF. The microstructure of joints was studied by optical microscopy (Scope Axio ZEISS), scanning electron microscope SEM (S-3400) with fast energy dispersion spectrum EDS analyzer, and selected area XRD (X’Pert3 Powder) analysis. Vickers microhardness tests for the weld carried out with a 10s load time and a 200g load. Tensile strength of the joints was measured by using universal testing machine (MTS Insight 10 kN) with cross head speed of 2mm/min.

Results and Discussion

Characterization of Joint

According to the previous research results, the microstructure, and mechanical properties of NiTi alloy/Ti alloy joint can be improved by adding appropriate interlayer materials, but the formation of brittle and hard Ti-Ni intermetallic compounds in the weld cannot be avoided. To further improve the mechanical properties of NiTi alloy/Ti alloy joint, the design idea of laser welding of NiTi alloy and Ti alloy assisted by metal transition layer is proposed in this paper. The purpose is to avoid the metallurgical reaction between Ti and Ni and improve the microstructure and mechanical properties of NiTi alloy/Ti alloy joint.

Macro-Characteristics

The optical microscopy image of the cross section of the joint is shown in (Figure 2a). The joint can fall into three parts: the fusion weld formed at the Ti alloy side, unmelted Ti alloy and the diffusion weld formed at the TiNi-Ti alloy interface. The fusion weld did not form Ti-Fe intermetallics due to the presence of unmelted Ti alloy. The average width of fusion weld, unmelted Ti alloy and diffusion weld was 1.8 mm, 0.35 mm and 0.17 mm, respectively. Because the microstructure of the fusion weld is quite different from that of the diffusion weld, the diffusion weld becomes black after corrosion. (Figure 2b) presents the optical image before corrosion of the diffusion weld. It does not present such defects as pores and macro-cracks. The unmelted part of Ti alloy acted as a heat sink absorbing a significant amount of energy from the welding pool and transferring it to the TiNi alloy side [20]. Hence, the filler metal of TiNi-Ti alloy interface had a high temperature during welding although it was not subjected to laser radiation. The temperature was high enough to promote atomic interdiffusion. This meets the temperature requirement for diffusion welding. Moreover, the local heating of the Ti alloy side caused uneven volume expansion and thermal stress was produced, which helped to obtain an intimate contact between the TiNi alloy, Cu-based fillers and Ti alloy surface. The high temperature and the intimate contact at the TiNi-Ti alloy interface provided favourable conditions for atomic (Cu, Zn, Ti, Ni) interdiffusion. Therefore, a diffusion weld was formed originated from atomic (Cu, Zn, Ti, Ni) interdiffusion at the Ti alloy-filler metal and filler metal-TiNi alloy interface. Additionally, the unmelted Ti alloy was beneficial to relieve and accommodate the thermal stress in the joint, which could help to improve the mechanical properties of the joints.

Figure 2: Macroscopic feature of the joint: (a) optical image of the cross section of the joint; (b) optical image before corrosion of the Ti alloy-TiNi alloy interface.

Microstructure Analysis

The optical image of the fusion weld is shown in (Figure 3a), and no defects were observed in it. SEM image of the fusion weld is shown in (Figure 3b). The fusion weld mainly consists of acicular structure. The optical image of the diffusion weld at NiTi-Ti alloy interface is shown in (Figure 3c). It can be observed that, the diffusion weld contained three zones marked as Ⅰ, Ⅱ and Ⅲ sorted by their morphologies and colours. (Figures 3d, 3e and 3f)correspond to the three zones in (Figure 3c), respectively. The compositions of each zone (denoted by letter A-C in (Figure 3)) were studied using SEM-EDS. EDS analysis was applied to these zones to measure the compositions of the reaction products and the results are listed in Table 1. Based on the previous analysis, the microstructure of the diffusion weld was mainly composed of Cu-based fillers. The chemical composition of zone Ⅰ was consistent with the Cu-based fillers. Based on the EDS analyses results and Cu-Zn phase diagram, the main microstructure of zone Ⅰ was defined as β-CuZn phase. When the laser beam was focused near the Ti alloy-filler metal interface, the element diffusion occurs immediately between the base materials and filler metal and causes its component to deviate from the original component. The interdiffusion of Cu, Zn, Ti and Ni elements occurred at diffusion welding interface (Ti alloy-filler metal and filler metal-NiTi alloy). At this moment, the dissolution of Ti and Ni into the filler metal occurred under the high concentration gradient, which formed solid-phase reaction layer, and this reaction layer exists only in the smaller region of the NiTi-Ti alloy interface. As shown in, zone Ⅱ and zone Ⅲ were reaction layers formed by element diffusion. Based on Ti-Cu-Ni phase diagram, the microstructure of zone Ⅱ was defined as TiCu₂+NiZn. Based on Cu-Ti-Zn phase diagram, the microstructure of zone Ⅲ was defined as Ti₃Cu₄+Ti₂Zn₃. Therefore, the main microstructures of diffusion weld were TiCu₂+NiZn, β-CuZn and Ti₃Cu₄+Ti₂Zn₃.

Table 1: The chemical composition of each phase in joint C (wt.%).

Figure 3: Microstructures of the joint : (a) optical image of fusion zone; (b) SEM image of fusion zone; (c) optical image of the diffusion weld; (b) SEM image of the zone I in Fig. 3c; (c) SEM image of the zone II in Fig. 3c; (d) SEM image of the zone III in Fig. 3c.

Figure 4: Vickers microhardness measurements at semi-height of joint (zero point situated in the center of joint).

Tensile Tests and Fracture Analysis

The maximum tensile strength of the joint was about 256 MPa (Figure 5a). The joint fractured in Ti alloy side of the diffusion weld during tensile tests (Figures 5b, 5c)shows fracture surface of the joint exhibiting typical brittle characteristics. Moreover, as shown in (Figure 5d), XRD analyses of fracture surface detected Ti₃Cu₄ and Ti₂Zn₃ phases. This confirmed the presence of Ti-Cu and Ti-Zn intermetallics at fracture surfaces. It should be noted that there was no Ti-Ni intermetallics in the brazed weld. Reaction layer at Ti alloy side in diffusion weld became the weak zone of the joint, which led to the failure in the tensile test.Based on the above results, the formation of Ti-Ni intermetallic compounds is avoided due to the presence of unmelted Ti alloy in the joint. Only a small amount of Ti-Cu intermetallic compounds is formed in the reaction layer at the NiTi-Ti alloy interface. Due to the rapid heating and cooling speed of laser welding, the holding time at high temperature is short, and it is easy to form a narrow reaction zone at the NiTi-Ti alloy interface. In addition, higher cooling rate inhibited the growth of dendrite structure in the reaction zone. Therefore, it is easy to obtain fine microstructure in the reaction zone, which is conducive to reducing the brittleness of the reaction layer. The results show that the formation of narrow reaction layer and fine metallurgical structure at the interface is one of the main reasons to improve the joint strength.

Figure 5: Tensile test results of joint: (a) Tensile test curve; (b) Fracture location; (c) SEM image of fracture surface; (d) XRD analysis results of fracture surface.

Conclusion

The possibility of welding processes for connect TC₄ Ti alloy to NiTi alloy with Cu-base filler metal was studied. The main conclusions are presented below. without filler metal, For joint with a laser beam offset of 1.2 mm for Ti alloy, the unmelted Ti alloy was selected as an barrier to avoid mixing of the NiTi alloy and Ti alloy which eliminated the formation of brittle Ti-Ni intermetallic in the joint . A diffusion weld was formed at the NiTi alloy-Ti alloy interface with the main microstructure of TiCu²⁺NiZn, β-CuZn and Ti₃Cu₄+Ti₂Zn₃. A great amount of atomic diffusion occurs at the NiTi-Ti alloy interface during welding, and the thickness of diffusion weld can reach hundreds of micrometres. The tensile resistance of the joint was determined by diffusion weld. The maximum tensile strength of joint was 256 MPa.

Read More About Lupine Publishers Journal of Material Science Please Click on below Link: https://lupine-publishers-material-science.blogspot.com/

Lupine Publishers | The Deja Vu Theory from my perspective

 Lupine Publishers | Journal of Psychology and Behavioral Sciences

Abstract

You might be surprise as this article progress to read line after line with knowing the fact of Humankind and the connection between Human-Life and Déjà vu theory. The word “déjà vu “belong to the French words repository and the meaning is “Already Seen”. Since several years déjà vu theory became a matter of debate among the space scientist and psychologist. The term belongs to human psychology but equally to space and universe domains as well. It’s a reference of existence of “Parallel Universes” called “Multiverse”. So, let us begin to the interesting write-up to know déjà vu occur when frequencies of two Universes match.

Keywords: Déjà Vu Theory; Parallel Universes; Multiverse; Human Psychology; Human Brain Quantum Psychology (Hbqp)

Introduction

Now let us begin with Déjà vu theory with my perspective and you decide your beliefs with your perspectives. Déjà vu is the French means “Already Seen” and the concept is already lived present situation/moment same as in past .i.e. several time we feel suddenly in the present moment of the life exactly same moment happened in the past and you strongly feel that you are in the same moment of past at present like function, event, seen, movement of life or whatever, and this occurrence called “Déjà vu occurred with you”. The psychologist understand Déjà vu is just a mental illness/state/ sickness/illusion which occurred when majority circumstances of present moment strongly “Match” passed past moment of life. But I raised questions why those strongly match? why this happened? And how match? Where answer from psychology is uncertain. Now let me know why Déjà vu occurred and when Déjà vu occurred with reference of Quantum Mechanics and theory of Universe with integration of psychology called “Human Brain Quantum Psychology (HBQP). Let us start with the introduction, is many more universes exist in space and our Universe not alone one and the answer is Big YES. Several theories proved that our Universe not a single and like our Universe infinite parallel Universes exist in deep-space called “Multiverse” and every Multiverse has several earth-like and earth planets in it and each Earth existence of life in all Universes. Hence our life and entity not only limited on single earth of single universe but on all earths of all Universes (Multiverse). Now after separate discussion on Déjà vu and Multiverse theories (on the basis of Cosmic Microwave Background (CMB), theory of Black/ White holes, Dark Matter, String Theory, Quantum Mechanics and Androphobic principles). I would like to discuss what is the relation between Déjà vu theory and Multiverse theory, how Déjà vu prove existence of Multiverse and why Déjà vu occurred several times with all of us in in routine life with the help of below model (Figure 1).

Consider the number of parallel Universes in Multiverse U1 (Our Universe), U2, U3, U4, U5 …… U∞ tuned with different frequencies and moving with different revolution frequencies F1, F2, F3, F4, F5 ……………Fx and each parallel universe separated by cosmic walls hence invisible and no interference with one another, but when any two three or more Universes in Multiverse (Parallel Universes) during revolution tuned on the same frequency (inphase) or frequency match of two universes in my model you can see our Universe U1 tuned or frequency match or in-phase with same frequency F1 with other Universe U4 of Multiverse, hence caused weakened the cosmic walls to superimpose and interference on one another and Universes U1 and U4 connected, where each Universe has Earth with Life of all of us using thoughts frequency and Quantum Psychology life of several connect of Universe U1 with Universe U4 with our existence on all Universes Earths. It is possible our life in comparison one earth from other back or forth with light years and space time might be possible what moment we living right now or at present in Universe U1 Earth already we lived same moment on Earth of Universe U4 three years before or might be live after some days, month or years due to back and forth of our lives. Therefore, window of our lives opens other tuned Universe to our Universe and we felt we already seen or passed from this moment, situation, scene, etc. called Déjà vu. Hence in this way there is a strong relation between human psychology, Déjà vu and Multiverse.

Figure 1: Different Revolution Frequencies and Parallel Universe.

Read More About Lupine Publishers Journal of Psychology Please Click on below Link:
https://lupine-publishers-psychology-journal.blogspot.com/