1,220 research outputs found
About the barotropic compressible quantum Navier-Stokes equations
In this paper we consider the barotropic compressible quantum Navier-Stokes
equations with a linear density dependent viscosity and its limit when the
scaled Planck constant vanish. Following recent works on degenerate
compressible Navier-Stokes equations, we prove the global existence of weak
solutions by the use of a singular pressure close to vacuum. With such singular
pressure, we can use the standard definition of global weak solutions which
also allows to justify the limit when the scaled Planck constant denoted by
tends to 0
Local Bulletin of Earthquakes in the Southern California Region 1 January 1963 to 31 December 1966
The Local Bulletin of the Pasadena Seismological Laboratory has been issued regularly since the beginning of 1934, and the present Bulletin covers the four-year period from 1 January 1963 to 31 December 1966
Star Clusters in the Nearby Late-Type Galaxy NGC 1311
Ultraviolet, optical and near infrared images of the nearby (D ~ 5.5 Mpc) SBm
galaxy NGC 1311, obtained with the Hubble Space Telescope, reveal a small
population of 13 candidate star clusters. We identify candidate star clusters
based on a combination of their luminosity, extent and spectral energy
distribution. The masses of the cluster candidates range from ~1000 up to
~100000 Solar masses, and show a strong positive trend of larger mass with
increasing with cluster age. Such a trend follows from the fading and
dissolution of old, low-mass clusters, and the lack of any young super star
clusters of the sort often formed in strong starbursts. The cluster age
distribution is consistent with a bursting mode of cluster formation, with
active episodes of age ~10 Myr, ~100 Myr and ~1 Gyr. The ranges of age and mass
we probe are consistent with those of the star clusters found in quiescent
Local Group dwarf galaxies.Comment: 21 pages, 11 figures, accepted by A
HIV Stigma: Perspectives from Kenyan Child Caregivers and Adolescents Living with HIV
Stigma shapes all aspects of HIV prevention and treatment, yet there are limited data on how HIV-infected youth and their families are affected by stigma in sub-Saharan Africa. The authors conducted a qualitative study using focus group discussions among 39 HIV-infected adolescents receiving care at HIV clinics in western Kenya and 53 caregivers of HIV-infected children. Participants felt that while knowledge and access to treatment were increasing, many community members still held negative and inaccurate views about HIV, including associating it with immorality and believing in transmission by casual interactions. Stigma was closely related to a loss of social and economic support but also included internalized negative feelings about oneself. Participants identified treatment-related impacts of stigma, including nonadherence, nondisclosure of status to child or others, and increased mental health problems. Qualitative inquiry also provided insights into how to measure and reduce stigma among affected individuals and families
Marital interaction theory: some implications for research
This project examines specific basic areas of marital interaction theory. Individual chapters are developed around the following themes: historical development of the theory of interaction; a theoretical discussion of selected concepts; personality as a determinant of interaction; communication in marriage; marital interaction patterns; methodology pertaining to research findings; and finally some implications for research which became apparent as this project developed. The project lays the conceptual groundwork for a series of empirical studies that will use the interactional approach as a theoretical base. The immediate purpose of this project therefore is to describe the important dimensions of the interactional approach as these pertain to marital interaction. Interaction is defined as a reciprocal relationship in which each person may produce effects upon the other. Here the essence of marriage is interaction; thus marital interaction is critical in its effect on the spouses and the continuity of the marriage. Some of the basic concepts of George Mead are described and it is suggested that they are essential elements of the interactional approach. The major assumptions of this approach are that a) human behavior cannot be derived or inferred from nonhuman forms, b) the social act is the primary analytic unit for an understanding of society and the personality, c) the human infant is potentially social, and d) the human being is actor as well as reactor. Personality is discussed as a determinant of the quality and quantity of marital interaction. The issue of personal competence is explored, particularly in respect to verbal ability. Communication, the process of influence, is defined for marital interaction and the consequent formation of patterns. Identification and classification of marital interaction patterns are limited to a description of selected examples from family research and the observations of clinicians. Patterns tend to be defined in psychological terms although communicative behavior is stressed. The absence of common criteria and terminology is noted. Description of dysfunctional patterns predominates. Two methods frequently used in recent studies of marital interaction are direct observation and analysis of reports from marital partners. It is suggested that a combination of these techniques could increase the quantity of information about marital interaction. Research questions focus on the problem of adult socialization, its implications for the establishment of marital interaction patterns, and the need to determine the relation between the interaction process and the functional or dysfunctional quality of the resultant pattern. An inseparable part of the aforementioned research areas is the function of communication. It is suggested that investigation of verbal communication might yield significant data for the understanding of the interaction process as it affects the personalities of the spouses and the formation of patterns
Assessment of algorithms for mitosis detection in breast cancer histopathology images
The proliferative activity of breast tumors, which is routinely estimated by counting of mitotic figures in hematoxylin and eosin stained histology sections, is considered to be one of the most important prognostic markers. However, mitosis counting is laborious, subjective and may suffer from low inter-observer agreement. With the wider acceptance of whole slide images in pathology labs, automatic image analysis has been proposed as a potential solution for these issues.
In this paper, the results from the Assessment of Mitosis Detection Algorithms 2013 (AMIDA13) challenge are described. The challenge was based on a data set consisting of 12 training and 11 testing subjects, with more than one thousand annotated mitotic figures by multiple observers. Short descriptions and results from the evaluation of eleven methods are presented. The top performing method has an error rate that is comparable to the inter-observer agreement among pathologists
Small contribution of gold mines to the ongoing tuberculosis epidemic in South Africa: a modeling-based study.
BACKGROUND: Gold mines represent a potential hotspot for Mycobacterium tuberculosis (Mtb) transmission and may be exacerbating the tuberculosis (TB) epidemic in South Africa. However, the presence of multiple factors complicates estimation of the mining contribution to the TB burden in South Africa. METHODS: We developed two models of TB in South Africa, a static risk model and an individual-based model that accounts for longer-term trends. Both models account for four populations - mine workers, peri-mining residents, labor-sending residents, and other residents of South Africa - including the size and prevalence of latent TB infection, active TB, and HIV of each population and mixing between populations. We calibrated to mine- and country-level data and used the static model to estimate force of infection (FOI) and new infections attributable to local residents in each community compared to other residents. Using the individual-based model, we simulated a counterfactual scenario to estimate the fraction of overall TB incidence in South Africa attributable to recent transmission in mines. RESULTS: We estimated that the majority of FOI in each community is attributable to local residents: 93.9% (95% confidence interval 92.4-95.1%), 91.5% (91.4-91.5%), and 94.7% (94.7-94.7%) in gold mining, peri-mining, and labor-sending communities, respectively. Assuming a higher rate of Mtb transmission in mines, 4.1% (2.6-5.8%), 5.0% (4.5-5.5%), and 9.0% (8.8-9.1%) of new infections in South Africa are attributable to gold mine workers, peri-mining residents, and labor-sending residents, respectively. Therefore, mine workers with TB disease, who constitute ~ 2.5% of the prevalent TB cases in South Africa, contribute 1.62 (1.04-2.30) times as many new infections as TB cases in South Africa on average. By modeling TB on a longer time scale, we estimate 63.0% (58.5-67.7%) of incident TB disease in gold mining communities to be attributable to recent transmission, of which 92.5% (92.1-92.9%) is attributable to local transmission. CONCLUSIONS: Gold mine workers are estimated to contribute a disproportionately large number of Mtb infections in South Africa on a per-capita basis. However, mine workers contribute only a small fraction of overall Mtb infections in South Africa. Our results suggest that curtailing transmission in mines may have limited impact at the country level, despite potentially significant impact at the mining level
A Geographic Information System for Invasive Species: Sahara Mustard Weed
Invasive plant species are aggressively spreading and threatening the Joshua Tree National Park (JOTR) ecosystem. Uncontrolled invasives will crowd out native plants and disrupt the natural habitat for desert animal species. JOTR needed a geographic information system (GIS) that can provide support for developing weed control plans against the Sahara mustard threat. This project addressed this need by developing a geodatabase for analysis, compiling required GIS feature layers, developing a mustard weed data model and a predictive spread model to aid in tracking the invasive weed. The data model identifies the essential data to collect for assessing and monitoring mustard weed observations. The compiled GIS feature layers consists of human activity factors (road network, trail, disturbed areas) and land factors (soil type, elevation, slope, vegetation cover, etc.). Human activity is a strong predictor of weed spread and these feature classes are the main element in one tool, the Predict Weed Spread Model. Land assessment analysis helps identify JOTR areas that are potentially high risk to mustard weed infestation. Results showed that a fundamental understanding of the Sahara mustard dynamics is required to model weed habitats and to predict weed spread that contributed to its existence and spread
Proceedings of the Regional Conference on Gender Issues in Communitv-Based Natural Resource Management CBNRM (Cresta Lodge, Harare : 24 - 27 August 1998)
A conference paper on the need to preserve trees in the Mozambican refugee camps in Malawi. Paper presented at regional conference on gender issues in community-based natural resource management (CBNRM), Cresta Lodge, Harare, 24 - 27 August.Malawi is a landlocked country that is bordered by Mozambique in the south and east, Zambia in the west and Tanzania in the north. The total land area is 119,140 square kilometres, 20% is covered by water and approximately five million hectares is covered by indigenous forests and woodland. Of this 20% consists of national parks and game reserves and 20% forest reserves and protected hill tops and 60% of natural woodland on customary land, 80,000 hectares is under exotic plantation management.
Between 1986 and 1994 Malawi hosted over a million Mozambican refugees who fled their country following the protracted armed struggle between FRELIMO soldiers and REMAMO bandits. The large influx had negative effects on the socio-economic spheres of the society as well as the natural resources: such as water, land, trees and forests. This paper will assess how gender sensitive the measures taken by different organizations were and the impact that this had on the afforestation project.The success of this conference and the publication of these proceedings has been possible through support from the US Agency for International Development (USAID
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