3,520 research outputs found
Spinorial Characterizations of Surfaces into 3-dimensional pseudo-Riemannian Space Forms
We give a spinorial characterization of isometrically immersed surfaces of
arbitrary signature into 3-dimensional pseudo-Riemannian space forms. For
Lorentzian surfaces, this generalizes a recent work of the first author in
to other Lorentzian space forms. We also characterize
immersions of Riemannian surfaces in these spaces. From this we can deduce
analogous results for timelike immersions of Lorentzian surfaces in space forms
of corresponding signature, as well as for spacelike and timelike immersions of
surfaces of signature (0,2), hence achieving a complete spinorial description
for this class of pseudo-Riemannian immersions.Comment: 9 page
Review of adipocere formation on decomposing bodies
Decomposition is a process that occurs in a body after death involving the breakdown of organic matter. Decomposition is influenced by a range of factors that act together with the general outcome being the complete degradation of a body.
Adipocere formation is a disruption of the typical decomposition process with the final result being the preservation of remains, human or animal. Adipocere arises from the decomposition of adipose tissue within the body. Adipocere is composed mostly of saturated fatty acids with hydroxy fatty acids, oxo fatty acids and fatty acid salts formed as byâproducts. The mechanism of formation is not fully understood although several theories have been proposed. Adipocere is not an end product and will degrade under the right circumstances,
mainly exposure to aerobic conditions and may also be consumed by macrofauna.
The environments adipocere has been found in have been studied to elucidate the many factors that may influence formation. Water, soil, and dry environments are all capable of producing conditions conducive to adipocere formation. The main factors known to promote formation in all environments are an anaerobic environment, sufficient adipose tissue, warm temperatures, a mildly alkaline pH, bacteria and moisture.
Adipocere may form partially within the soft tissues or they may turn completely into adipocere, preserving the internal organs and bones which may also form adipocere. Formation can occur in as little as a day or form over many years.
Studying adipocere formation is important in forensic science as it may aid forensic professionals in their casework in terms of postâmortem interval and ause/manner of death determination and comparison between similar, previously reported cases and a current case may be useful in aiding the process of the investigation.
Additional research is needed in the area of adipocere degradation as there is little literature on it. The determination of the postâmortem interval is complicated by adipocere formation and there is still not a reliable way to estimate it in bodies with adipocere formation
Observation of nano-indent induced strain fields and dislocation generation in silicon wafers using micro-raman spectroscopy and white beam x-ray topography
In the semiconductor manufacturing industry, wafer handling introduces micro-cracks at the wafer edge. During heat treatment these can produce larger, long-range cracks in the wafer which can cause wafer breakage during manufacture. Two complimentary techniques, micro-Raman spectroscopy (ÎŒRS) and White Beam Synchrotron X-ray Topography (WBSXRT) were employed to study both the micro-cracks and the associated strain fields produced by nano-indentations in Si wafers, which were used as a means of introducing controlled strain in the wafers. It is shown that both the spatial lateral and depth distribution of these long range strain fields are relatively isotropic in nature. The Raman spectra suggest the presence of a region under tensile strain beneath the indents, which can indicate a crack beneath the indent and the data strongly suggests that there exists a minimum critical applied load below which cracking will not initiate
Experiences of Family Carers of People Diagnosed with Borderline Personality disorder
This is the peer reviewed version of the following article: [Lawn, S. and McMahon, J. (2015), Experiences of family carers of people diagnosed with borderline personality disorder. Journal of Psychiatric and Mental Health Nursing, 22: 234â243. ], which has been published in final form at [http://doi.org/10.1111/jpm.12193]. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.There is limited understanding of the experience of family carers of people diagnosed with borderline personality disorder (BPD). This study aimed to explore their experiences of being carers, their attempts to seek help for the person diagnosed with BPD, and their own carer needs. An invitation to participate in an online survey was distributed to carers across multiple consumer and carer organisations and mental health services, by the Private Mental Health Consumer Carer Network (Australia) in 2011. Responses from 121 carers showed that they experience significant challenges and discrimination when attempting to engage with and seek support from health services. Comparison with consumersâ experiences (reported elsewhere) showed that these carers have a clear understanding of the discrimination faced by people with this diagnosis, largely because they also experience exclusion and discrimination. Community carer support services were perceived as inadequate. General practitioners were an important source of support; however, they and other service providers need more education and training to support attitudinal change to address discrimination, recognise carersâ needs and provide more effective support. This study provides the first detailed account of BPD carersâ experiences across a broad range of support needs and interactions with community supports and health services
Predicting the long-term impact of antiretroviral therapy scale-up on population incidence of tuberculosis.
OBJECTIVE: To investigate the impact of antiretroviral therapy (ART) on long-term population-level tuberculosis disease (TB) incidence in sub-Saharan Africa. METHODS: We used a mathematical model to consider the effect of different assumptions about life expectancy and TB risk during long-term ART under alternative scenarios for trends in population HIV incidence and ART coverage. RESULTS: All the scenarios we explored predicted that the widespread introduction of ART would initially reduce population-level TB incidence. However, many modelled scenarios projected a rebound in population-level TB incidence after around 20 years. This rebound was predicted to exceed the TB incidence present before ART scale-up if decreases in HIV incidence during the same period were not sufficiently rapid or if the protective effect of ART on TB was not sustained. Nevertheless, most scenarios predicted a reduction in the cumulative TB incidence when accompanied by a relative decline in HIV incidence of more than 10% each year. CONCLUSIONS: Despite short-term benefits of ART scale-up on population TB incidence in sub-Saharan Africa, longer-term projections raise the possibility of a rebound in TB incidence. This highlights the importance of sustaining good adherence and immunologic response to ART and, crucially, the need for effective HIV preventive interventions, including early widespread implementation of ART
Noise induced rupture process: Phase boundary and scaling of waiting time distribution
A bundle of fibers has been considered here as a model for composite
materials, where breaking of the fibers occur due to a combined influence of
applied load (stress) and external noise. Through numerical simulation and a
mean-field calculation we show that there exists a robust phase boundary
between continuous (no waiting time) and intermittent fracturing regimes. In
the intermittent regime, throughout the entire rupture process avalanches of
different sizes are produced and there is a waiting time between two
consecutive avalanches. The statistics of waiting times follows a Gamma
distribution and the avalanche distribution shows power law scaling, similar to
what have been observed in case of earthquake events and bursts in fracture
experiments. We propose a prediction scheme that can tell when the system is
expected to reach the continuous fracturing point from the intermittent phase.Comment: 6 pages, 8 figure
Stillbirth should be given greater priority on the global health agenda
Stillbirths are largely excluded from international measures of mortality and morbidity. Zeshan Qureshi and colleagues argue that stillbirth should be higher on the global health agenda
Dynamic instabilities of fracture under biaxial strain using a phase field model
We present a phase field model of the propagation of fracture under plane
strain. This model, based on simple physical considerations, is able to
accurately reproduce the different behavior of cracks (the principle of local
symmetry, the Griffith and Irwin criteria, and mode-I branching). In addition,
we test our model against recent experimental findings showing the presence of
oscillating cracks under bi-axial load. Our model again reproduces well
observed supercritical Hopf bifurcation, and is therefore the first simulation
which does so
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