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Early attempts at surgical sperm retrieval focused on creating artificial spermatoceles in men with vas aplasia or uncorrectable obstructive azoospermia. The collected sperm was used for intrauterine insemination, and success was rare. The major impetus to sperm retrieval came soon after the development of intracytoplasmic sperm injection, which enabled high fertilization rates and live-birth rates using sperm from the testis or epididymis. Initial cases involved men with obstructive azoospermia and sperm were retrieved microsurgically from the epididymis. Subsequently, testicular sperm, obtained by conventional biopsy, were used when sperm could not be aspirated from the epididymis. Retrieval was simplified with the development of percutaneous techniques for extracting epididymal or testicular sperm. Techniques became more complex and varied when it was realized that men with nonobstructive azoospermia may also have sperm in their testes, but these sperm-containing tubules could be very localized. Hence, a variety of percutaneous and open methods were developed that could sample the testes extensively. Initially the sampling was blind, through multidirectional aspiration or multiple random biopsies. However, these blind techniques could still miss localized areas of sperm production. Also, multiple biopsies were shown to cause testicular damage. Hence, microdissection testicular sperm extraction (mTESE) was developed, which involved visual inspection of the entire testicular parenchyma under high magnification. mTESE gives the highest sperm retrieval rates, especially when the testes are small or atrophic.
Infertility is a difficult and stressful condition that impacts about 15 percent of couples attempting to conceive for the first time . In about half of these cases a male factor is causative and, in general, constitutes a major health issue. While the cornerstone of the evaluation of male infertility remains the basic semen analysis, the sperm penetration assay (SPA) is a useful laboratory test for predicting the capacity of an individual male’s spermatozoa to fertilize a female oocyte. This assay supplements standard semen parameters and aids clinicians in identifying couples who will have a high chance of success with in vitro fertilization. The test was first developed in the 1970s and gained momentum when, in 1976, Yanagimachi and colleagues noted that enzymatic removal of the zona pellucida of hamster ova allowed penetration by human spermatozoa . The goal of the SPA is to measure the spermatozoa’s ability to undergo capacitation, acrosome reaction, fusion and penetration through the oolemma (egg plasma membrane), and decondensation within the cytoplasm of hamster oocytes resulting in the formation of the male pronucleus .
We discuss the question of learning distributions over permutations of a given set of choices, options or items based on partial observations. This is central to capturing the so-called “choice’’ in a variety of contexts. The question of learning distributions over permutations arises beyond capturing “choice’’ too, e.g., tracking a collection of objects using noisy cameras, or aggregating ranking of web-pages using outcomes of multiple search engines. Here we focus on learning distributions over permutations from marginal distributions of two types: first-order marginals and pair-wise comparisons. We emphasize the ability to identify the entire distribution over permutations as well as the “best ranking’’.
Virtual reality (VR) is a promising tool with the potential to enhance care of cognitive and affective disorders in the aging population. VR has been implemented in clinical settings with adolescents and children; however, it has been less studied in the geriatric population.
The objective of this study is to determine the existing levels of evidence for VR use in clinical settings and identify areas where more evidence may guide translation of existing VR interventions for older adults.
Design and measurements:
We conducted a systematic review in PubMed and Web of Science in November 2019 for peer-reviewed journal articles on VR technology and its applications in older adults. We reviewed article content and extracted the number of study participants, study population, goal of the investigation, the level of evidence, and categorized articles based on the indication of the VR technology and the study population.
The database search yielded 1554 total results, and 55 articles were included in the final synthesis. The most represented study design was cross-sectional, and the most common study population was subjects with cognitive impairment. Articles fell into three categories for VR Indication: Testing, Training, and Screening. There was a wide variety of VR environments used across studies.
Existing evidence offers support for VR as a screening and training tool for cognitive impairment in older adults. VR-based tasks demonstrated validity comparable to some paper-based assessments of cognition, though more work is needed to refine diagnostic specificity. The variety of VR environments used shows a need for standardization before comparisons can be made across VR simulations. Future studies should address key issues such as usability, data privacy, and confidentiality. Since most literature was generated from high-income countries (HICs), it remains unclear how this may be translated to other parts of the world.
In 1988, Malaysia’s Constitution was amended to separate the Syariah and civil jurisdictions of the courts. Henceforth, matters involving Syariah (Islamic religious law) would only be litigated in the Syariah courts and not the civil courts. This move proved problematic especially since the Federal Constitution regulates all fundamental rights and liberties – including the right to religious freedom – while religion is regulated by the constituent states. State legislatures are thus empowered to create and punish offences against precepts of Islam. This chapter analyses how common law principles of administrative law have been applied and developed in Malaysia by studying their interaction with the administration of Syariah law. More specifically, it asks: How do the civil courts exercise its powers of judicial review in cases involving Syariah and the exercise of powers by both secular and religious authorities in such cases? It traces the patterns of judicial application and assessment of key administrative law principles such as natural justice, reasonableness, and proportionality and argues that while English precedents continue to be cited, these same precedents are often jettisoned and modified when it conflicts with the political power and primacy of Islamic law.
The COVID-19 outbreak has caused challenges for healthcare systems worldwide. Recent data indicates that the psychological impact has differed with respect to occupation. In many countries, medical residents have been on the front line of this pandemic. However, data on the psychological impact of infectious disease outbreaks, and COVID-19 in particular, on medical residents are relatively lacking.
The aim of our study was to assess the psychological impact of the COVID-19 pandemic on medical residents working on the front and second line.
An electronic survey was sent to all medical residents in Qatar. Depression, anxiety and stress were assessed by the Depression, Anxiety and Stress Scale – 21 Items. Professional quality of life was measured by the Professional Quality of Life measure.
Of the 640 medical residents contacted, 127 (20%) responded. A considerable proportion of residents reported symptoms of depression (42.5%), anxiety (41.7%) and stress (30.7%). Multivariate analysis of variance showed significant effects of seniority in residency, with junior residents having poorer outcomes. In addition, there was a statistically significant interaction effect with moderate effect sizes between gender and working on the front line, as well as gender, working on the front line and seniority, on mental health outcomes.
The COVID-19 pandemic may have a negative impact on junior residents’ mental health. Preventive measures to reduce stress levels and easy access to professional mental health services are crucial.
Antimicrobial spectrum scoring is a method to quantify the spectrum of antimicrobial utilization. Herein, we applied a locally adapted scoring system, with other pre-existing scoring systems, using a data set of prophylactically administered antibiotics following a 2-stage antimicrobial stewardship program (ASP) intervention in a population of patients on extracorporeal membrane oxygenation (ECMO).
This paper investigates the dynamics of an underwater vehicle-manipulator system (UVMS) consisting of a two-link flexible-joint manipulator affixed to an autonomous underwater vehicle. The quasi-Lagrange formulation is utilized in deriving a realistic mathematical model of the UVMS considering joints’ friction, hysteretic coupling between the joints and links, and the nonlinear hydrodynamic forces acting on the system, such as added mass, viscous damping, buoyancy, drag, and vortex-induced forces. Numerical simulations are performed to demonstrate the effects of hydrodynamic forces and system coupling between the vehicle and the manipulator and the joints and the links on the precise positioning of the end effector.
We assessed long-term incidence and prevalence trends of dementia and parkinsonism across major ethnic and immigrant groups in Ontario.
Linking administrative databases, we established two cohorts (dementia 2001–2014 and parkinsonism 2001–2015) of all residents aged 20 to 100 years with incident diagnosis of dementia (N = 387,937) or parkinsonism (N = 59,617). We calculated age- and sex-standardized incidence and prevalence of dementia and parkinsonism by immigrant status and ethnic groups (Chinese, South Asian, and the General Population). We assessed incidence and prevalence trends using Poisson regression and Cochran–Armitage trend tests.
Across selected ethnic groups, dementia incidence and prevalence were higher in long-term residents than recent or longer-term immigrants from 2001 to 2014. During this period, age- and sex-standardized incidence of dementia in Chinese, South Asian, and the General Population increased, respectively, among longer-term immigrants (by 41%, 58%, and 42%) and long-term residents (28%, 7%, and 4%), and to a lesser degree among recent immigrants. The small number of cases precluded us from assessing parkinsonism incidence trends. For Chinese, South Asian, and the General Population, respectively, prevalence of dementia and parkinsonism modestly increased over time among recent immigrants but significantly increased among longer-term immigrants (dementia: 134%, 217%, and 117%; parkinsonism: 55%, 54%, and 43%) and long-term residents (dementia: 97%, 132%, and 71%; parkinsonism: 18%, 30%, and 29%). Adjustment for pre-existing conditions did not appear to explain incidence trends, except for stroke and coronary artery disease as potential drivers of dementia incidence.
Recent immigrants across major ethnic groups in Ontario had considerably lower rates of dementia and parkinsonism than long-term residents, but this difference diminished with longer-term immigrants.
The ten-item short form of the Autism-Spectrum Quotient (AQ-10) has been used to efficiently assess autistic traits in the general population; however, the psychometric properties of the AQ-10 in terms of its internal reliability and its unifactorial structure have recently been questioned. In the present study (N = 797), whether the internal reliability is increased when the AQ-10 is applied with six rather than the conventional four response categories has been investigated. Moreover, correlational and confirmatory factor analyses were conducted to examine the reason for potential inhomogeneity within the AQ-10. The results suggest that the internal reliability of the AQ-10 was slightly increased but is still unsatisfactory, likely due to the incompatibility of items from two subdimensions: attention to detail and imagination. With six of the AQ-10 items, crucial aspects of the autistic personality may be measured, but other important aspects would be neglected; thus, the measure requires further psychometric development.
The rapid progress in the performance of today's sophisticated transmission electron microscopes also demands computational and educational tools capable of simulating the intricacy of electron image formation. The tools ideally should be widely accessible to the microscopy community and capable of covering both the breadth and depth demanded by modern materials science. Here, a cloud-based microscopy simulation platform, called cloudEMAPS and powered by cloud computing and modern server-client web programming architecture, is described. Compared to the current desktop solutions for electron microscopy simulations, cloud computing offers the unique advantages of on-demand, data sharing, high-performance computation and internet easy access using the state-of-the-art web infrastructure. This article will demonstrate these advantages using examples of interactive simulations of electron diffraction patterns and aberration-corrected electron optics.
India has introduced health technology assessment (HTA) as a tool for improving the allocation of health resources. The core mandate of HTA in India (HTAIn) is to undertake critical appraisal of available technologies, identify cost-effective interventions, and help the government pursue evidence-informed decisions regarding public health expenditures. We conducted a systematic review to assess economic evaluation studies published in the last four years from India.
Economic evaluations published from September 2015 to September 2019 were identified by searching various databases, including PubMed, Scopus, Embase, The Cochrane Library, and CINAHL according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guideline. Cost-effectiveness studies and HTAs reported or conducted in India were included. Two independent reviewers performed the final selection of studies by assessing the full-text articles and conducted the data extraction. Differences of opinions were resolved through discussion and mutual consensus.
After screening 2,837 articles, seventy met the inclusion criteria and were selected. The articles predominantly used secondary data (70%) to evaluate the cost effectiveness of an innovation. Among the technologies assessed, fifty-seven percent were curative in nature and most commonly addressed infectious diseases (27%), closely followed by non-communicable diseases, and maternal and child health. Principally, the cost effectiveness of a technology was expressed in terms of disability-adjusted or quality-adjusted life-years. Only two studies reported negative findings.
HTA can play a pivotal role in equipping policy makers and public health payers to make appropriate decisions for healthcare budget allocations when mapped with the true disease burden of the population. It is important to highlight negative results and to create a national repository of HTA studies to facilitate faster adoption of best practices in India.
To assess influenza symptoms, adherence to mask use recommendations, absenteesm and presenteeism in acute care healthcare workers (HCWs) during influenza epidemics.
The TransFLUas influenza transmission study in acute healthcare prospectively followed HCWs prospectively over 2 consecutive influenza seasons. Symptom diaries asking for respiratory symptoms and adherence with mask use recommendations were recorded on a daily basis, and study participants provided midturbinate nasal swabs for influenza testing.
In total, 152 HCWs (65.8% nurses and 13.2% physicians) were included: 89.1% of study participants reported at least 1 influenza symptom during their study season and 77.8% suffered from respiratory symptoms. Also, 28.3% of HCW missed at least 1 working day during the study period: 82.6% of these days were missed because of symptoms of influenza illness. Of all participating HCWs, 67.9% worked with symptoms of influenza infection on 8.8% of study days. On 0.3% of study days, symptomatic HCWs were shedding influenza virus while at work. Among HCWs with respiratory symptoms, 74.1% adhered to the policy to wear a mask at work on 59.1% of days with respiratory symptoms.
Respiratory disease is frequent among HCWs and imposes a significant economic burden on hospitals due to the number of working days lost. Presenteesm with respiratory illness, including influenza, is also frequent and poses a risk for patients and staff.
Antimicrobial resistance is a major problem in India with limited understanding of whether this issue is related to systems, prescriber characteristics, patient characteristics, or diagnostic technologies. In our survey, most of the issues lie in the easy availability of antimicrobials and the lack of electronic storage of medical and microbiological records.
Treatment of hypoplastic left heart syndrome varies across institutions. This study examined the impact of introducing a standardised programme.
This retrospective cohort study evaluated the effects of a comprehensive strategy on 1-year transplant-free survival with preserved ventricular and atrioventricular valve (AVV) function following a Norwood operation. This strategy included standardised operative and perioperative management and dedicated interstage monitoring. The post-implementation cohort (C2) was compared to historic controls (C1). Outcomes were assessed using logistic regression and Kaplan–Meier analysis.
The study included 105 patients, 76 in C1 and 29 in C2. Groups had similar baseline characteristics, including percentage with preserved ventricular (96% C1 versus 100% C2, p = 0.28) and AVV function (97% C1 versus 93% C2, p = 0.31). Perioperatively, C2 had higher indexed oxygen delivery (348 ± 67 ml/minute/m2 C1 versus 402 ± 102ml/minute/m2 C2, p = 0.015) and lower renal injury (47% C1 versus 3% C2, p = 0.004). The primary outcome was similar in both groups (49% C1 and 52% C2, p = 0.78), with comparable rates of death and transplantation (36% C1 versus 38% C2, p = 0.89) and ventricular (2% C1 versus 0% C2, p = 0.53) and AVV dysfunction (11% C1 versus 11% C2, p = 0.96) at 1-year. When accounting for cohort and 100-day freedom from hospitalisation, female gender (OR 3.7, p = 0.01) increased and ventricular dysfunction (OR 0.21, p = 0.02) and CPR (OR 0.11, p = 0.002) or ECMO use (OR 0.15, p = 001) decreased the likelihood of 1-year transplant-free survival.
Standardised perioperative management was not associated with improved 1-year transplant-free survival. Post-operative ventricular or AVV dysfunction was the strongest predictor of 1-year mortality.
Understanding individual differences in attitudes to autism is crucial for improving attitudes and reducing stigma towards autistic people, yet there is limited and inconsistent research on this topic. This is compounded by a lack of appropriate measures and multivariate analyses. Addressing these issues, using up-to-date measures and multiple linear regression, we examined the relative contributions of participant age, sex, autism knowledge, level of contact with autistic people, and autistic traits to attitudes towards autistic people. We found that greater autism knowledge and higher levels of contact, but no other variables, were uniquely predictive of attitudes towards autistic people. We conclude that, in addition to public awareness campaigns to raise knowledge of autism, it may be important to increase contact between autistic and non-autistic people to improve public attitudes towards autistic people.
A compact antenna module with a single band notch at wireless local area network (WLAN) (5.725–5.825 GHz) for ultra-wideband (UWB) multiple input multiple output (MIMO) applications is proposed. Proposed antenna which acquires size of 0.299 λ × 0.413 λ × 0.005 λ mm3 at 3.1 GHz consists of two symmetrical radiators placed side by side on global merchandise link (GML) 1000 substrate (εr = 3.2, tan δ = 0.004). Isolation between the antenna elements is >18 dB in the whole UWB band, which is achieved by introducing the vertical stub and H-slot between the monopole radiators in the ground plane. The simulated and measured results of the antenna system are in good agreement. The proposed antenna covers entire UWB with impedance bandwidth (|S11| < −15 dB) from 3.1 to 11 GHz except at WLAN notched band. The designed antenna module bears low envelope correlation coefficient and minimal multiplexing efficiency hence fulfilling criteria suitable for various wireless MIMO applications.
The snow leopard Panthera uncia is the flagship species of the high mountains of the Himalayas. There is potentially continuous habitat for the snow leopard along the northern border of Nepal, but there is a gap in information about the snow leopard in Gaurishankar Conservation Area. Previous spatial analysis has suggested that the Lamabagar area in this Conservation Area could serve as a transboundary corridor for snow leopards, and that the area may connect local populations, creating a metapopulation. However, there has been no visual confirmation of the species in Lamabagar. We set 11 infrared camera traps for 7 months in Lapchi Village of Gaurishankar Conservation Area, where blue sheep Pseudois nayaur, musk deer Moschus leucogaster and Himalayan tahr Hemitragus jemlahicus, all snow leopard prey species, had been observed. In November 2018 at 4,100 m, 5 km south-west of Lapchi Village, one camera recorded three images of a snow leopard, the first photographic evidence of the species in the Conservation Area. Sixteen other species of mammals were also recorded. Camera-trap records and sightings indicated a high abundance of Himalayan tahr, blue sheep and musk deer. Lapchi Village may be a potentially important corridor for snow leopard movement between the east and west of Nepal and northwards to Quomolongma National Park in China. However, plans for development in the region present increasing threats to this corridor. We recommend development of a transboundary conservation strategy for snow leopard conservation in this region, with participation of Nepal, China and international agencies.