On the Newtonian Anisotropic Configurations

In this paper we are concerned with the effects of anisotropic pressure on the boundary conditions of anisotropic Lane-Emden equation and homology theorem. Some new exact solutions of this equation are derived. Then some of the theorems governing the Newtonian perfect fluid star are extended taking the anisotropic pressure into account

Guaranteed Minimum-Rank Solutions of Linear Matrix Equations via Nuclear Norm Minimization

The affine rank minimization problem consists of finding a matrix of minimum rank that satisfies a given system of linear equality constraints. Such problems have appeared in the literature of a diverse set of fields including system identification and control, Euclidean embedding, and collaborative filtering. Although specific instances can often be solved with specialized algorithms, the general affine rank minimization problem is NP-hard. In this paper, we show that if a certain restricted isometry property holds for the linear transformation defining the constraints, the minimum rank solution can be recovered by solving a convex optimization problem, namely the minimization of the nuclear norm over the given affine space. We present several random ensembles of equations where the restricted isometry property holds with overwhelming probability. The techniques used in our analysis have strong parallels in the compressed sensing framework. We discuss how affine rank minimization generalizes this pre-existing concept and outline a dictionary relating concepts from cardinality minimization to those of rank minimization

Evaluation and Determination of the Appropriate Method for Assessing Optimum Utilisation Rate of \u3cem\u3eEurotia Ceratoides\u3c/em\u3e in Upland Grasslands of Iran

Determination of optimum utilisation rate for different range species is an important factor in assessing range grazing capacity. The vast rangelands in Iran with diverse vegetation types require an accurate, economic and quick method to determine the optimum utilisation rate for different range species. This experiment was conducted to determine the most appropriate method to determine the optimum utilisation rate for Eurotia ceratoides, which is one of the important grass species in upland grasslands in Iran

A type-2 fuzzy system model for reducing bullwhip effects in supply chains and its application in steel manufacturing

AbstractThe purpose of this paper is to evaluate and reduce the bullwhip effect in fuzzy environments by means of type-2 fuzzy methodology. In order to reduce the bullwhip effect in a supply chain, we propose a new method for demand forecasting. First, the demand data of a real steel industry in Canada is clustered with an interval type-2 fuzzy c-regression clustering algorithm. Then, a novel interval type-2 fuzzy hybrid expert system is developed for demand forecasting. This system uses Fuzzy Disjunctive Normal Forms (FDNF) and Fuzzy Conjunctive Normal Forms (FCNF) for the aggregation of antecedents. An interval type-2 fuzzy order policy is developed to determine orders in the supply chain. Then, the results of the proposed method are compared with the type-1 fuzzy expert system as well as the type-1 fuzzy time series method in the literature. The results show that the bullwhip effect is significantly reduced; also, the system has less error and high accuracy

Epidemiology of female reproductive cancers in Iran: Results of the gholestan population-based cancer registry

Background: Malignancies of the female reproductive tract are estimated to be the third most common group of cancers in women. Objectives: We here aimed to present their epidemiological features in Golestan provincelocated in Northeast of Iran. Materials and Methods: Data on primary female reproductive cancers diagnosed between 2004-2010 were obtained from Golestan Population-based Cancer Registry (GPCR). CanReg-4 and SPSS software were used for data entry and analysis. Age standardized incidence rates (ASR) (per 100,000 person-years) were calculated using the world standard population. Poisson regression analysis was used to compare incidence rates. P-values of less than 0.05 were considered as significant. Results: A total of 6,064 cancer cases were registered in Golestan females in the GPCR during 2004-2010, of which 652 cases (11%) were female reproductive cancers. Cancers of the ovary (ASR=6.03) and cervix (ASR=4.97) were the most common. We found significant higher rates in females living in cities than in villages. Our results showed a rapid increase in age specific incidence rates of female reproductive cancers at the age of 30 years. Conclusions: We found significant higher rates of female reproductive cancers among residents of cities than villages. Differences in the prevalence of risk factors including reproductive behavior between the two populations may partly explain such diversity. Our results also showed a rapid increase in incidence rates of these cancers in young age females. Further studies are warranted to determine risk factors of female reproductive cancers in our population

Individual-level risk factors for suicide mortality in the general population: an umbrella review

Background Deaths by suicide remain a major public health challenge worldwide. Identifying and targeting risk factors for suicide mortality is a potential approach to prevention. We aimed to summarise current knowledge on the range and magnitude of individual-level risk factors for suicide mortality in the general population and evaluate the quality of the evidence. Methods In this umbrella review, five bibliographic databases were systematically searched for articles published from database inception to Aug 31, 2022. We included meta-analyses of observational studies on individual-level risk factors for suicide mortality in the general population. Biological, genetic, perinatal, and ecological risk factors were beyond the scope of this study. Effect sizes were synthesised and compared across domains. To test robustness and consistency of the findings, evidence for small-study effects and excess significance bias (ie, the ratio between the overall meta-analysis effect size and that of its largest included study) was examined, and prediction intervals were calculated. Risk of bias was assessed by the Risk of Bias in Systematic Reviews instrument. The protocol was pre-registered with PROSPERO (CRD42021230119). Findings We identified 33 meta-analyses on 38 risk factors for suicide mortality in the general population. 422 (93%) of the 454 primary studies included in the meta-analyses were from high-income countries. A previous suicide attempt and suicidal ideation emerged as strong risk factors (with effect sizes ranging from 6 to 16). Psychiatric disorders were associated with a greatly elevated risk of suicide mortality, with risk ratios in the range of 4–13. Suicide risk for physical illnesses (such as cancer and epilepsy) and sociodemographic factors (including unemployment and low education) were typically increased two-fold. Contact with the criminal justice system, state care in childhood, access to firearms, and parental death by suicide also increased the risk of suicide mortality. Among risk factors for which sex-stratified analyses were available, associations were generally similar for males and females. However, the quality of the evidence was limited by excess significance and high heterogeneity, and prediction intervals suggested poor replicability for almost two-thirds of identified risk factors. Interpretation A wide range of risk factors were identified across various domains, which underscores suicide mortality as a multifactorial phenomenon. Prevention strategies that span individual and population approaches should account for the identified factors and their relative strengths. Despite the large number of risk factors investigated, few associations were supported by robust evidence. Evidence of causal inference will need to be tested in high-quality study designs. Funding Wellcome Trust

Access to and perceived unmet need for mental health services and support in a community sample of UK adolescents with and without experience of childhood adversity

Aims. Children and adolescents with a history of adverse childhood experiences (ACEs) are more likely than their peers to develop mental health difficulties, but not enough is known about their help-seeking behaviours and preferences. We aimed to determine whether and how ACEs are associated with access to and perceived unmet need for mental health services and support amongst secondary school students. Methods: We used multi-level logistic regression with data from the 2020 OxWell Student Survey to assess whether ACEs were associated with (1) prior access to mental health support and (2) perceived unmet need for mental health services in a community sample of English secondary school students. We assessed ACEs as a cumulative score from the Center for Youth Wellness Adverse Childhood Experiences Questionnaire: Teen Self-Report version and accounted for current mental health difficulties as measured by the 25-item Revised Children’s Anxiety and Depression Scale (RCADS). Results: Our analysis included 2018 students across 64 schools, of whom 29.9% (598/2002) reported prior access to mental health support and 34.1% (469/1377) reported a perceived unmet need for services. In the unadjusted models, the cumulative ACE score was significantly positively associated with both prior access to mental health support (odds ratio (OR)=1.36; 95% confidence interval (CI) 1.29–1.43) and perceived unmet need for mental health services (OR=1.47; 95% CI 1.37–1.59), meaning that students who had experienced adversity had a greater chance of having previously accessed support as well as perceiving an unmet need for services. After adjusting for mental health difficulties and other sociodemographic variables, cumulative ACE scores were positively associated with prior access (adjusted OR (aOR)=1.25; 95% CI 1.17–1.34 with a significant interaction between RCADS and ACE scores, aOR=0.88; 95% CI 0.84–0.93) as well as perceived unmet need (aOR=1.32; 95% CI 1.21–1.43 with a significant interaction between RCADS and ACE scores, aOR=0.85; 95% CI 0.78–0.91). Conclusions: Although it is encouraging that adolescents with experience of adversity are more likely than their peers with similar levels of depression and anxiety symptoms to have accessed mental health support, there remains a concern that those who have not accessed support are more likely to perceive an as-yet unmet need for it. Mental health support must be available, accessible, and acceptable to all who need it, especially for those groups that traditionally have not accessed services, including the more marginalised and vulnerable populations