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When faced with the task of solving hyperbolic partial differential equations (PDEs), high order, strong stability-preserving (SSP) time integration methods are often needed to ensure preservation of the nonlinear strong stability properties of spatial discretizations. Among such methods, SSP second derivative time-stepping schemes have been recently introduced and used for evolving hyperbolic PDEs. In previous works, coupling of forward Euler and a second derivative formulation led to sufficient conditions for a second derivative general linear method (SGLM), which preserve the strong stability properties of spatial discretizations. However, for such methods, the types of spatial discretizations that can be used are limited. In this paper, we use a formulation based on forward Euler and Taylor series conditions to extend the SSP SGLM framework. We investigate the construction of SSP second derivative diagonally implicit multistage integration methods (SDIMSIMs) as a subclass of SGLMs with order
and stage order
up to order eight, where r is the number of external stages and s is the number of internal stages of the method. Proposed methods are examined on some one-dimensional linear and nonlinear systems to verify their theoretical order, and show potential of these schemes in preserving some nonlinear stability properties such as positivity and total variation.
The aim of the present study was to investigate the effect of cigarette smoke condensate (CSC) on in vitro development of mouse embryos. In total 3000 NMRI mice 2PN embryos were divided into six groups (n = 500). The test group was exposed to 20, 40, 80, 160 or 320 μg/ml of CSC. In the control group, CSC was not added to the culture medium during the development of 2PN embryos. The effects of 20 and 80 μg/ml of CSC on genes involved in pluripotency and apoptosis, and also, the aryl hydrocarbon receptor gene was assessed in the blastocysts. Our results showed that CSC had an adverse effect on the viability of mouse embryos at the concentrations of 80, 160 and 320 μg/ml compared with the control group (P < 0.05). In contrast, it had positive effects on the viability of mouse embryos at the concentrations of 20 and 40 μg/ml compared with the control group (P < 0.05). The 20 and 80 μg/ml concentrations of CSC increased the expression of pluripotency, apoptotic, and aryl hydrocarbon receptor genes in the blastocyst embryo stage compared with the control group (P < 0.05). It can be concluded that concentrations higher than 40 μg/ml of CSC have an adverse effect on mouse embryo development in the preimplantation stages. Also, 20 and 80 μg/ml concentrations of CSC have a significant effect on the expression of pluripotency, apoptotic, and the aryl hydrocarbon receptor genes in the blastocyst embryo stage compared with the control group.
Sea urchins have important effects on marine ecosystems such as rocky shores and coral reefs across the world. However, species diversity and molecular phylogeny of most echinoid taxa are poorly known in Iran. In this study, the phylogenetic relationships of one of the most abundant species of the genus Echinometra in the Persian Gulf were examined. Echinoids were collected from the intertidal zone of Qeshm Island and Lengeh Port on March and December 2017. Morphological criteria based on valid identification keys combined with molecular analysis of a fragment of the mitochondrial cytochrome c oxidase subunit I (COI) protein-coding gene were used to delineate Echinometra species. Our analyses showed that all specimens (N = 15) belong to Echinometra sp. EZ. Tree topologies indicated that our individuals from two sampling sites formed a distinct monophyletic clade with E. sp. EZ, demonstrating high support values. This is the first phylogenetic analysis of E. sp. EZ from Iran.
Afghanistan is one of the few places where the category of bachah—the beardless young male—has maintained its aesthetic and erotic aspects in the public imagination. This article provides an introduction to the history of the various arrangements of man-bachah relationships in Afghanistan from the rise of the Afghan kingdom in the late eighteenth century. By looking at both primary and secondary sources, alongside ethnographic materials gathered during fieldwork in Afghanistan between 2016 and 2021, this article shows how the content and implications of the category of bachah have been in constant flux and intimately connected to wider social, political, and economic developments both inside the country and beyond.
The objective of this study was to investigate the association between food patterns and serum vitamin D concentrations in US adults. Data from two cycles of National Health and Nutrition Examination Surveys, 2003–2004 and 2005–2006, were used (n 6637). Three major food patterns were derived using factor analysis. These three patterns were labeled as meat and processed meat foods (MPF), vegetables, fruit, nuts, and whole grains (VFNW), and sweet, snack, and beverage pattern (SSB). Serum vitamin D was measured with RIA and later standardized to reflect the assay changes over time. In multivariate-adjusted regression analysis, the MPF pattern was significantly, inversely associated with serum vitamin D concentrations (P < 0·001). However, the relation between the VFNW pattern and serum vitamin D was non-linear (P < 0·001). There was no relationship between SSB pattern and serum vitamin D in US adults. In conclusion, persons with a high intake of meat and processed meats are associated with lower serum vitamin D concentrations. Reducing processed foods and emphasizing VFNW will be beneficial from a health perspective.
The paper deals with the construction of explicit Nordsieck second derivative general linear methods with s stages of order p with
and high stage order
with inherent Runge–Kutta or quadratic stability properties. Satisfying the order and stage order conditions together with inherent stability conditions leads to methods with some free parameters, which will be used to obtain methods with a large region of absolute stability. Examples of methods with r external stages and
up to order five are given, and numerical experiments in a fixed stepsize environment are presented.
The Makira Natural Park (Makira) is the largest terrestrial protected area in Madagascar, supporting nearly 200,000 people living around the park, who derive a significant proportion of their animal-source foods from hunting. Makira is currently managed with three different policies: (1) traditional management with no external assistance; (2) community-based forest management (Gestion Contractualisée des Forêts; GCF) with non-governmental support and externally developed policies; and (3) strict external management policies (Zone d’Occupation Controlée; ZOC), meaning a zone of controlled residence for communities inside the core protected area. Here, we longitudinally assess the impacts of these policies on wildlife hunting and consumption by using a difference-in-differences method to evaluate policy efficacy. We found that externally developed conservation policies led to drastically reduced wildlife hunting and consumption in Makira. We also found that public education in the form of environmental awareness-raising, conducted 1 year before adoption, led to a greater concealment of hunting behaviours. Overall, wildlife hunting and consumption have decreased in the Makira region since the adoption of GCF and ZOC policies and could be effective at reducing the unsustainable wildlife hunting across the Makira, particularly when supported by economic development and the creation of alternative sources of livelihood and food.
Obesity and depression are increasing in prevalence and have become key issues in the public health of the modern day. We performed a meta-review to summarise the association between obesity and depression in adults.
A systematic literature search was undertaken on MEDLINE, PsychINFO, EMBASE and Web of Science for systematic reviews (SRs) with or without meta-analyses (MA) on the association between obesity and depression in adults (>18 years) published before 18 September 2018. Any approach to define depressive disorders (e.g. via structured interview or code in medical file) was accepted. Likewise, any method to assess obesity was accepted. Screening, data extraction and quality assessment was completed by two reviewers independently, with a third reviewer to arbitrate any disagreement. AMSTAR 2 tool was used to assess the methodological quality and risk of bias of the pertinent SRs/MAs.
After duplicate removal, we identified 6007 potentially pertinent citations. Following, title, abstract and full-text screening, 10 studies were included in the review; nine SRs with MAs and one SR. A statistically significant association between obesity and depression was reported in all nine SRs with MAs, with odds ratios ranging from 1.18 (95% CI = 1.11-1.26) to 1.57 (95% CI = 1.53-2.01). Increased severity of obesity (body mass index over 40) was associated with a greater odds of becoming depressed. Odds of developing depression were greater for obese females, compared to obese males, but this difference was not statistically significant. Depression was shown to be a significant risk factor for future obesity in all four relevant MAs with odds ratios ranging from 1.18 (95% CI = 1.13-1.23) to 1.40 (95% CI = 1.14-1.71) . Depressed adolescent females had the highest odds of becoming obese, significantly more so than depressed adolescent males and depressed adults. The quality of the included studies were mixed with five scoring moderate quality, three low quality and two critically low quality.
The findings suggest a reciprocal association between depression and obesity, which may be modulated by age and gender. Future research should assess the potential effect of obesity and depression severity more carefully while also exploring the underlying mechanisms. These results warrant the investigation of the effect of obesity or depression intervention on the outcomes of the other.
Compressed sensing allows recovery of image signals using a portion of data – a technique that has drastically revolutionized the field of through-the-wall radar imaging (TWRI). This technique can be accomplished through nonlinear methods, including convex programming and greedy iterative algorithms. However, such (nonlinear) methods increase the computational cost at the sensing and reconstruction stages, thus limiting the application of TWRI in delicate practical tasks (e.g. military operations and rescue missions) that demand fast response times. Motivated by this limitation, the current work introduces the use of a numerical optimization algorithm, called Limited Memory Broyden–Fletcher–Goldfarb–Shanno (LBFGS), to the TWRI framework to lower image reconstruction time. LBFGS, a well-known Quasi-Newton algorithm, has traditionally been applied to solve large scale optimization problems. Despite its potential applications, this algorithm has not been extensively applied in TWRI. Therefore, guided by LBFGS and using the Euclidean norm, we employed the regularized least square method to solve the cost function of the TWRI problem. Simulation results show that our method reduces the computational time by 87% relative to the classical method, even under situations of increased number of targets or large data volume. Moreover, the results show that the proposed method remains robust when applied to noisy environment.
ABSTRACT IMPACT: Specific recommendations will be suggested in this presentation as to how a health equity lens can be applied to implementation science frameworks. OBJECTIVES/GOALS: This systematic review consolidated literature on how implementation science (IS) frameworks (e.g., RE-AIM) have been used in cancer prevention services (e.g., screening, tobacco cessation programs)
to reduce health disparities. METHODS/STUDY POPULATION: The systematic review was conducted in accordance with PRISMA and registered with PROSPERO. Searches were conducted in Ovid MEDLINE, PubMed, PsycINFO, CINAHL, and EMBASE between January-May 2020. Search strategies used the combinations of terms related to implementation science frameworks, cancer prevention and/or intervention, and all search algorithms were validated by a public health librarian. RESULTS/ANTICIPATED RESULTS: A total of 1,025 articles were screened and 84 were deemed eligible for full-text screening. After full-text screening, n=27 articles were included for data abstraction and synthesis. Of the 27 studies that used an implementation science framework, only one-third of studies (N=9, 33.3%) used an IS framework to address cancer-related health disparities. Of those nine studies, six of them used the Consolidated Framework for Implementation Research (CFIR) to guide, inform, and/or adapt the implementation of a cancer prevention intervention to target health disparities. However, the variability in how this framework was applied remains a challenge. DISCUSSION/SIGNIFICANCE OF FINDINGS: Recommendations for how various IS frameworks can be used to address cancer prevention disparities will be presented, such as, guiding principles on how to intentionally select domains within the CFIR that will capture input from key stakeholders in health disparities populations.
Ultrasound is the investigation of choice for the initial assessment of fibroids. However, the density, number, size or location of the fibroids can degrade the image quality due to the attenuation of the sound waves. Magnetic resonance imaging (MRI) does not suffer the same limitations and is not operator-dependent; it provides detailed and consistent assessment, making it the ideal tool to evaluate fibroid characteristics over time, such as change in size or amount of necrosis following treatment.