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Sample records for male black howlers

  1. The Missing Fellow: First Description of the Trypanoxyuris pigrae Male (Nematoda: Oxyuridae), a Parasite of the Black Howler Monkey (Alouatta pigra) in Mexico.

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    Solórzano-García, B; Andrade, D M Güiris; de León, G Pérez-Ponce

    2017-08-01

    The first morphological description of the male of Trypanoxyuris pigrae Solórzano-García, Nadler, and Pérez-Ponce de León, 2016 , is presented in this study. Morphological data are supported by molecular data. Specimens of T. pigrae were recovered after the necropsy of a roadkill black howler monkey (Alouatta pigra) in southeastern Mexico. Males of T. pigrae are characterized by having 3 notched lips and a long esophagus with a posterior bulb; they also show a single crested lateral alae, a single spicule, and 4 caudal papillae. Morphological features coincide with those of the previously described T. pigrae females, and molecular profiles confirmed species identification. Males of T. pigrae are very similar to those of Trypanoxyuris minutus, another species of pinworm that also parasitizes the black howler monkey, A. pigra; however, the shape of the lips represents a very reliable diagnostic feature. Because of this, detailed en face observations are recommended to discriminate between these pinworm species.

  2. Feeding ecology of the black howler monkey (Alouatta pigra) in northern Belize.

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    Silver, S C; Ostro, L E; Yeager, C P; Horwich, R

    1998-01-01

    We studied the feeding ecology of the black howler monkey (Alouatta pigra) from March 1994 to April 1995 in the Community Baboon Sanctuary in northern Belize, Central America. Activity and diet composition were recorded using continuous focal animal sampling. Diet composition was compared with the relative abundance of plant parts eaten by the howlers within the study site. The study animals spent an average of 24.4% of their time feeding, 61.9% resting, and approximately 9.8% traveling. In contrast to previously published reports on A. pigra, we found the diet composition to be similar to that of other Alouatta species (conforming to the folivore/frugivore profile), with 41% of feeding time spent eating fruit, 45% foliage, and 11% flowers. This contrast may indicate a wide degree of dietary flexibility that allows A. pigra to inhabit a variety of habitat types. We suggest that a high level of resource abundance throughout the year makes the Community Baboon Sanctuary excellent habitat for Alouatta pigra.

  3. Demographic survey of black howler monkey (Alouatta pigra) in the Lachuá Eco-region in Alta Verapaz, Guatemala.

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    Rosales-Meda, Marleny; Estrada, Alejandro; López, Jorge E

    2008-03-01

    Guatemala harbors three species of primates (Alouatta palliata, Alouatta pigra and Ateles geoffroyi), but the distribution and state of conservation of populations of these species are poorly documented. In the case of A. pigra, populations have been studied recently and documented in several sites in Mexico and Belize, and only in one site in Guatemala (Tikal National Park). In this study, we report first-time population data for A. pigra existing in the Lachuá Eco-region in northwestern Guatemala. Surveys were conducted between September 2002 and April 2003 in the northern portion (32 km2) of the Lachuá National Park (LLNP; 145 km2) and in a fragmented landscape north of the protected area. In this latter area we surveyed a large forest fragment (17.14 km2), "Nueve Cerros", and 26 small forest fragments that ranged in size from 0.01 to 3.9 km2. Surveys resulted in a total count of 414 howler monkeys of which 403 belonged to 80 mixed-sex groups, four were solitary males, two were solitary females and five were found in two male groups. Standardized sampling effort among sites indicated 16.7 monkeys/100 survey hours at LLNP, 35.8 individuals/100 survey hours at "Nueve Cerros" and 71.0+/-62.2 individuals/100 survey hours in the forest fragments. Mean group size varied from 4.07 individuals at LLNP to 5.19 individuals in the forest fragments. Conservation problems for the black howler population surveyed are discussed, along with possible conservation scenarios.

  4. Black and gold howler monkeys (Alouatta caraya) as sentinels of ecosystem health: patterns of zoonotic protozoa infection relative to degree of human-primate contact.

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    Kowalewski, Martin M; Salzer, Johanna S; Deutsch, Joseph C; Raño, Mariana; Kuhlenschmidt, Mark S; Gillespie, Thomas R

    2011-01-01

    Exponential expansion of human populations and human activities within primate habitats has resulted in high potential for pathogen exchange creating challenges for biodiversity conservation and global health. Under such conditions, resilient habitat generalists such as black and gold howler monkeys (Alouatta caraya) may act as effective sentinels to overall ecosystem health and alert us to impending epidemics in the human population. To better understand this potential, we examined noninvasively collected fecal samples from black and gold howler monkeys from remote, rural, and village populations in Northern Argentina. We examined all samples (n=90) for the zoonotic protozoa Cryptosporidium sp. and Giardia sp. via immunofluorescent antibody (IFA) detection. All samples were negative for Cryptosporidium sp. The prevalence of Giardia sp. was significantly higher at the rural site (67%) compared with the remote forest (57%) and village (40%) sites. A lack of Cryptosporidium sp. in all samples examined suggests that this pathogen is not a natural component of the howler parasite communities at these sites and that current land-use patterns and livestock contact are not exposing Argentine howler monkeys to this pathogen. High prevalence of Giardia sp. at all sites suggests that howler monkeys may serve as a viable reservoir for Giardia. Significantly higher prevalence of Giardia sp. at the rural site, where primate-livestock contact is highest, suggests the presence of multiple Giardia clades or increased exposure to Giardia through repeated zoonotic transmission among nonhuman primates, livestock, and/or people. These results highlight the need for future research into the epidemiology, cross-species transmission ecology, and clinical consequences of Giardia and other infectious agents not only in humans and livestock, but also in the wild animals that share their environments. © 2010 Wiley-Liss, Inc.

  5. Black howler monkey (Alouatta pigra) activity, foraging and seed dispersal patterns in shaded cocoa plantations versus rainforest in southern Mexico.

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    Zárate, Diego A; Andresen, Ellen; Estrada, Alejandro; Serio-Silva, Juan Carlos

    2014-09-01

    Recent evidence has shown that primates worldwide use agroecosystems as temporary or permanent habitats. Detailed information on how these primates are using these systems is scant, and yet their role as seed dispersers is often implied. The main objective of this study was to compare the activity, foraging patterns and seed dispersal role of black howler monkeys (Alouatta pigra) inhabiting shaded cocoa plantations and rainforest in southern Chiapas, Mexico. We gathered data on three monkey groups living in shaded cocoa plantations and three groups living in rainforest, using focal sampling, and collecting fecal samples. General activity and foraging patterns were similar in both habitats, with the exception that monkeys in the cocoa habitat spent more time feeding on petioles. Monkeys in shaded cocoa plantations dispersed 51,369 seeds (4% were seeds ≥3 mm width) of 16 plant species. Monkeys in the rainforest dispersed 6,536 seeds (78% were seeds ≥3 mm width) of 13 plant species. Our data suggest that the difference between habitats in the proportion of large versus small seeds dispersed reflects differences in fruit species abundance and availability in cocoa versus forest. Mean seed dispersal distances were statistically similar in both habitats (cocoa = 149 m, forest = 86 m). We conclude that the studied cocoa plantations provide all elements necessary to constitute a long-term permanent habitat for black howler monkeys. In turn, howler monkeys living in these plantations are able to maintain their functional role as seed dispersers for those native tree and liana species present within their areas of activities. © 2014 Wiley Periodicals, Inc.

  6. The gut microbiota appears to compensate for seasonal diet variation in the wild black howler monkey (Alouatta pigra).

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    Amato, Katherine R; Leigh, Steven R; Kent, Angela; Mackie, Roderick I; Yeoman, Carl J; Stumpf, Rebecca M; Wilson, Brenda A; Nelson, Karen E; White, Bryan A; Garber, Paul A

    2015-02-01

    For most mammals, including nonhuman primates, diet composition varies temporally in response to differences in food availability. Because diet influences gut microbiota composition, it is likely that the gut microbiota of wild mammals varies in response to seasonal changes in feeding patterns. Such variation may affect host digestive efficiency and, ultimately, host nutrition. In this study, we investigate the temporal variation in diet and gut microbiota composition and function in two groups (N = 13 individuals) of wild Mexican black howler monkeys (Alouatta pigra) over a 10-month period in Palenque National Park, Mexico. Temporal changes in the relative abundances of individual bacterial taxa were strongly correlated with changes in host diet. For example, the relative abundance of Ruminococcaceae was highest during periods when energy intake was lowest, and the relative abundance of Butyricicoccus was highest when young leaves and unripe fruit accounted for 68 % of the diet. Additionally, the howlers exhibited increased microbial production of energy during periods of reduced energy intake from food sources. Because we observed few changes in howler activity and ranging patterns during the course of our study, we propose that shifts in the composition and activity of the gut microbiota provided additional energy and nutrients to compensate for changes in diet. Energy and nutrient production by the gut microbiota appears to provide an effective buffer against seasonal fluctuations in energy and nutrient intake for these primates and is likely to have a similar function in other mammal species.

  7. Risk factors connected to gastrointestinal parasites in mantled Alouatta palliata mexicana and black howler monkeys Alouatta pigra living in continuous and in fragmented rainforests in Mexico

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    Genoveva TREJO-MACÍAS, Alejandro ESTRADA

    2012-06-01

    Full Text Available In this study we document the prevalence of gastrointestinal parasites (helminths and protozoans found in fecal samples of populations of Alouatta palliata mexicana and of A. pigra in Los Tuxtlas and in Palenque, southeast Mexico, and its relation to habitat condition, sex/age and season. Nineteen parasite morphotypes were detected in the fecal samples from populations of the two howler monkeys, of which 58% were shared by both species. When considering all parasite species, populations of the two howler species were more likely to be parasitized in fragmented habitat compared to continuous habitat. Individuals of both howler monkey species that lived in fragmented habitat had a higher prevalence of Controrchis biliophilus. A. p. mexicana individuals had a higher prevalence of Trypanoxyuris minutus than A. pigra, probably the result of the larger group sizes found in the former species, and T. minutus was more likely to be found in A. palliata individuals that lived in fragmented habitat. Adult A. p. mexicana males had a higher risk of being parasitized compared to adult females, but these differences were not detected in A. pigra. Parasite species such as Entamoeba sp., Nematoda sp. 28, Nematoda sp. B and Parabronema sp. where only found during the wet season in both howler monkey species. Populations of both howler monkey species had a higher prevalence of Nematoda sp. A in the wet season and Ascaridae eggs were only detected during the wet season in A. pigra. Other parasites detected displayed no clear seasonal pattern [Current Zoology 58 (3: 375-383, 2012].

  8. Primates living outside protected habitats are more stressed: the case of black howler monkeys in the Yucatán Peninsula.

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    Ariadna Rangel-Negrín

    Full Text Available The non-invasive monitoring of glucocorticoid hormones allows for the assessment of the physiological effects of anthropogenic disturbances on wildlife. Variation in glucocorticoid levels of the same species between protected and unprotect areas seldom has been measured, and the available evidence suggests that this relationship may depend on species-specific habitat requirements and biology. In the present study we focused on black howler monkeys (Alouatta pigra, a canopy-dwelling primate species, as a case study to evaluate the physiological consequences of living in unprotected areas, and relate them with intragroup competition and competition with extragroup individuals. From February 2006 to September 2007 we collected 371 fecal samples from 21 adults belonging to five groups (two from protected and three from unprotected areas in Campeche, Mexico. We recorded agonistic interactions within groups and encounters with other groups (1,200 h of behavioral observations, and determined fecal glucocorticoid metabolite (FGM concentrations with radioimmunoassays. We used linear mixed models and Akaike's information criterion to choose the best model explaining variation in FGM concentrations between protected and unprotected areas calculated from five categorical variables: habitat type (protected vs. unprotected, participation in agonistic interactions, intergroup encounters, sex and female reproductive state, and season. The best model included habitat type, the interaction between habitat type and agonism, and the interaction between habitat type and season. FGM concentrations were higher in unprotected habitats, particularly when individuals were involved in agonistic interactions; seasonal variation in FGM concentrations was only detected in protected habitats. High FGM concentrations in black howler monkeys living in unprotected habitats are associated with increased within-group food competition and probably associated with exposure to

  9. Pinworm diversity in free-ranging howler monkeys (Alouatta spp.) in Mexico: Morphological and molecular evidence for two new Trypanoxyuris species (Nematoda: Oxyuridae).

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    Solórzano-García, Brenda; Nadler, Steven A; Pérez-Ponce de León, Gerardo

    2016-10-01

    Two new species of Trypanoxyuris are described from the intestine of free-ranging howler monkeys in Mexico, Trypanoxyuris multilabiatus n. sp. from the mantled howler Alouatta palliata, and Trypanoxyuris pigrae n. sp. from the black howler Alouatta pigra. An integrative taxonomic approach is followed, where conspicuous morphological traits and phylogenetic trees based on DNA sequences are used to test the validity of the two new species. The mitochondrial cytochrome oxidase subunit 1 gene, and the nuclear ribosomal 18S and 28S rRNA genes were used for evolutionary analyses, with the concatenated dataset of all three genes used for maximum likelihood and Bayesian phylogenetic analyses. The two new species of pinworms from howler monkeys were morphologically distinct and formed reciprocally monophyletic lineages in molecular phylogenetic trees. The three species from howler monkeys, T. multilabiatus n. sp., T. pigrae n. sp., and Trypanoxyuris minutus, formed a monophyletic group with high bootstrap and posterior probability support values. Phylogenetic patterns inferred from sequence data support the hypothesis of a close evolutionary association between these primate hosts and their pinworm parasites. The results suggest that the diversity of pinworm parasites from Neotropical primates might be underestimated. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  10. Survey of black howler (Alouatta pigra) and spider (Ateles geoffroyi) monkeys in the Mayan sites of Calakmul and Yaxchilán, Mexico and Tikal, Guatemala.

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    Estrada, Alejandro; Luecke, Leandra; Van Belle, Sarie; Barrueta, Emilio; Meda, Marleny Rosales

    2004-01-01

    Surveys of populations of spider and howler monkeys were conducted at the Mayan sites of Calakmul and Yaxchilán, Mexico and Tikal, Guatemala. The forests in which these sites are found are part of the largest landmass of tropical rain forests present in Mesoamerica, encompassing about 4 million ha. Triangulation of monkey vocalization combined with ground surveys was used to determine the presence of howler and spider monkey groups. Howler monkey mean troop size at these sites varied from 6.6+/-2.1 individuals in Yaxchilán to 7.5+/-1.9 in Calakmul to 8.7+/-2.2 in Tikal. Density estimates varied from 12.8 individuals/km(2 )in Yaxchilán to 15.2 individuals/km(2 )in Calakmul to 17.8 individuals/km(2 )in Tikal. Mean spider monkey subgroup size varied from 4.7+/-2.6 individuals in Tikal to 5.6+/-3.0 individuals in Yaxchilán to 7.7+/-3.8 individuals in Calakmul. Spider monkey density varied from 17.0 individuals/km(2 )in Yaxchilán to 17.2 individuals/km(2 )in Calakmul to 56.4 individuals/km(2 )in Tikal. All sightings of both howler and spider monkeys at the three sites were in undisturbed rain forest vegetation and spider monkeys in general were more frequently sighted at higher tree heights than howlers. We discuss the value of further acquiring data on howler and spider monkey populations existing in extensive forest tracts and on the conservation value for both primate species of the forests surrounding the Mayan ruins found in this area of Mesoamerica.

  11. A demographic history of a population of howler monkeys (Alouatta palliata living in a fragmented landscape in Mexico

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    Jurgi Cristóbal Azkarate

    2017-08-01

    Full Text Available Long-term field studies are critical for our understanding of animal life history and the processes driving changes in demography. Here, we present long-term demographic data for the northernmost population of mantled howler monkeys (Alouatta palliata residing in a highly anthropogenically fragmented landscape in Los Tuxtlas, Mexico. We carried out 454 monthly group visits to 10 groups of mantled howler monkeys between 2000 and 2011. The population remained relatively stable over the 11-year study period, with an overall increase in the total number of individuals. Birth rates and inter-birth intervals were comparable to those of howler monkeys at non-fragmented sites, suggesting that living in a fragmented landscape did not affect the reproductive output of our study population. Moreover, despite the landscape, dispersal events were commonplace, including many secondary dispersals (individuals emigrating from groups that they had previously immigrated into. Finally, we found a marked effect of seasonality on the dynamics of our study population. In particular, the period of lowest temperatures and resource scarcity between November and March was associated with higher mortality and reproductive inhibition, while the period of resource abundance between April and May was associated with the majority of conceptions and weaning of offspring. This, in turn, could be influencing dispersal patterns in our study area, as male howler monkeys seem to time some of their immigrations into new groups to coincide with the start of the period of higher fertility, while females preferentially joined new groups several months before the onset of this period. These data have important implications for the conservation and management of howler monkeys in fragmented landscapes, as well as for our understanding of the effect of seasonality over howler monkey dispersal, reproduction and survival.

  12. Dental disorders in brown howler monkeys (Alouatta guariba clamitans) maintained in captivity.

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    Dias Neto, Ramiro das Neves; Fecchio, Roberto Silva; Rahal, Sheila Canevese; Teixeira, Carlos Roberto; Gioso, Marco Antônio; Pereira, Camila Trevisan; Santos, Maria Augusta Adami Pereira Dos; Milanelo, Liliane

    2016-04-01

    The aim of this study was to investigate dental disorders of brown howler monkeys maintained in captivity. The hypothesis is that the identification and diagnosis of the lesions may contribute to control and prevention. Sixteen intact brown howler monkeys (Alouatta guariba clamitans), eight females and eight males, weighing from 3.9 to 6.8 kg, were studied. Under general anesthesia, the teeth were evaluated by visual inspection, probing, palpation, and intra-oral radiographic exam. The findings were registered on a dental chart specific for primates. Of the 16 monkeys evaluated in the present study, 94% (n = 15) had some type of dental disorder. The lesions observed were dental calculus (88%), dental wear (81%), missing teeth (38%), gingivitis (19%), gingival recession (6%), dental fracture (19%), pulp exposure (19%), and dental staining (25%). Alouatta guariba clamitans maintained in captivity have a high rate of dental problems. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  13. Parasites of free-ranging black howler monkeys (Alouatta pigra) from Belize and Mexico.

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    Vitazkova, Sylvia K; Wade, Susan E

    2006-11-01

    Parasites are important members of the ecological web within which an animal lives, and can be used as indicators of ecosystem health. However, few baseline parasitological data are available for free-ranging animals, particularly for the black howler monkey (Alouatta pigra). In this study a total of 283 fecal samples were collected from 50 individually identified A. pigra during 2003 and 2004 and examined for parasites. The samples were processed using standard quantitative centrifugation concentration techniques, with sugar and zinc sulfate used as flotation media. The slides were examined using bright-field and phase microscopy. Antigen capture enzyme-linked immunosorbent assays (ELISAs) were used to detect protozoa. Four parasites were detected: 1) Controrchis biliophilus (Dicrocoeliidae), 2) Trypanoxyuris minutus (Oxyuridae), 3) Giardia sp. (Hexamitidae), and 4) Entamoeba sp. (Endamoebidae). Controrchis biliophilus was detected in 80% (wet season) and 81% (dry season) of the A. pigra samples; Trypanoxyuris minutus was detected in 8% (wet season) and 27% (dry season) of samples; and Giardia sp. was detected in 40% (wet season) and 27% (dry season) of samples. For the first time, DNA from Giardia sp.-positive fecal samples was extracted from A. pigra. Alouatta pigra individuals that lived near human settlements in Belize were infected with Giardia duodenalis (syn. G. lamblia, G. intestinalis) Assemblages A and B. These results suggest that G. duodenalis is transmitted from people and/or domestic animals to A. pigra. (c) 2006 Wiley-Liss, Inc.

  14. Detection of the mosquito-borne flaviviruses, West Nile, Dengue, Saint Louis Encephalitis, Ilheus, Bussuquara, and Yellow Fever in free-ranging black howlers (Alouatta caraya of Northeastern Argentina.

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    María A Morales

    2017-02-01

    Full Text Available Several medically important mosquito-borne flaviviruses have been detected in Argentina in recent years: Dengue (DENV, St. Louis encephalitis (SLEV, West Nile (WNV and Yellow Fever (YFV viruses. Evidence of Bussuquara virus (BSQV and Ilheus virus (ILHV activity were found, but they have not been associated with human disease. Non-human primates can act as important hosts in the natural cycle of flaviviruses and serological studies can lead to improved understanding of virus circulation dynamics and host susceptibility. From July-August 2010, we conducted serological and molecular surveys in free-ranging black howlers (Alouatta caraya captured in northeastern Argentina. We used 90% plaque-reduction neutralization tests (PRNT90 to analyze 108 serum samples for antibodies to WNV, SLEV, YFV, DENV (serotypes 1and 3, ILHV, and BSQV. Virus genome detection was performed using generic reverse transcription (RT-nested PCR to identify flaviviruses in 51 antibody-negative animals. Seventy animals had antibodies for one or more flaviviruses for a total antibody prevalence of 64.8% (70/108. Monotypic (13/70, 19% and heterotypic (27/70, 39% patterns were differentiated. Specific neutralizing antibodies against WNV, SLEV, DENV-1, DENV-3, ILHV, and BSQV were found. Unexpectedly, the highest flavivirus antibody prevalence detected was to WNV with 9 (8.33% monotypic responses. All samples tested by (RT-nested PCR were negative for viral genome. This is the first detection of WNV-specific antibodies in black howlers from Argentina and the first report in free-ranging non-human primates from Latin-American countries. Given that no animals had specific neutralizing antibodies to YFV, our results suggest that the study population remains susceptible to YFV. Monitoring of these agents should be strengthened to detect the establishment of sylvatic cycles of flaviviruses in America and evaluate risks to wildlife and human health.

  15. Timing of births in sympatric brown howler monkeys (Alouatta fusca clamitans) and northern muriquis (Brachyteles arachnoides hypoxanthus).

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    Strier, K B; Mendes, S L; Santos, R R

    2001-10-01

    We monitored the birth patterns of sympatric brown howler monkeys (Alouatta fusca clamitans) and northern muriquis (Brachyteles arachnoides hypoxanthus) during a 4-yr period from October 1996 to August 2000 at the Estação Biológica de Caratinga, Minas Gerais, Brazil. Brown howler monkey births (n = 34) occurred throughout the year, and birth frequencies did not differ between rainy and dry season months. The aseasonal birth patterns of the howler monkeys differed significantly from the dry season concentration and dry month peak in muriqui births (n = 23). We found no effects of infant sex or the number of females on interbirth intervals (IBIs) in our 10 howler monkey study troops. IBIs of brown howler monkeys averaged 21.2 +/- 2.5 mo (n = 8, median = 21.0 mo), and were significantly shorter following dry season births than rainy season births. Their IBIs and yearling survivorship (74%) were similar to those reported for other species of howler monkeys, but yearling survivorship was much lower than that of muriquis (94%), whose IBIs were more than 12 mo longer than those of the howler monkeys. Our study extends comparative knowledge of birth patterns in Alouatta to a poorly known species, and provides insights into the different ways in which diet and life history may affect the timing of births in large-bodied platyrrhines under the same seasonal ecological conditions. Copyright 2001 Wiley-Liss, Inc.

  16. Molecular characterization of trypanosomatid infections in wild howler monkeys (Alouatta caraya in northeastern Argentina

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    Mariela Florencia Martínez

    2016-08-01

    Full Text Available The transmission of Trypanosoma cruzi by vectors is confined to the Americas, and the infection circulates in at least two broadly defined transmission cycles occurring in domestic and sylvatic habitats. This study sought to detect and characterize infection by T. cruzi and other trypanosomes using PCR strategies in blood samples from free-ranging howler monkeys, Alouatta caraya, in the northeastern Argentina. Blood samples were collected at four sites with variable levels of habitat modification by human activity. PCR was conducted using primers for kinetoplast DNA, satellite DNA and ribosomal DNA of the trypanosomatid parasites. Ribosomal and satellite DNA fragments were sequenced to identify the trypanosomatid species and to characterize the discrete typing units (DTUs of T. cruzi. Overall, 46% (50/109 of the howlers were positive according to the kDNA-PCR assay, but only 7 of the howlers were positive according to the SatDNA-PCR protocol. We sequenced the amplicons of the satellite DNA obtained from five specimens, and the sequences were 99% and 100% similar to T. cruzi. A sequence typical of DTU T. cruzi I was found in one howler monkey from the “remote” site, while sequences compatible with DTUs II, V, and VI were found in howlers from the “remote”, “rural” and “village” sites. We detected 96% positive samples for RibDNA-PCR, 9 of which were sequenced and displayed 99% identity with Trypanosoma minasense, while none showed identity with T. cruzi. The results demonstrated the presence of T. cruzi and a species closely related to T. minasense in blood samples from free-ranging A. caraya, belonging to different T. cruzi DTUs circulating in these howler monkey populations. The results obtained in this study could help evaluate the role of A. caraya as a reservoir of T. cruzi in regions where Chagas disease is hyper-endemic and where the human-wildlife interface is increasing.

  17. Structure of Black Male Students Academic Achievement in Science

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    Rascoe, Barbara

    Educational policies and practices have been largely unsuccessful in closing the achievement gap between Black and White students "Schwartz, 2001". This achievement gap is especially problematic for Black students in science "Maton, Hrabrowski, - Schmitt, 2000. Given the fact that the Black-White achievement gap is still an enigma, the purpose of this article is to address the Black female-Black male academic achievement gap in science majors. Addressing barriers that Black male students may experience as college science and engineering majors, this article presents marketing strategies relative to politics, emotional intelligence, and issues with respect to how science teaching, and Black male students' responses to it, are different. Many Black male students may need to experience a paradigm shift, which structures and enhances their science achievement. Paradigm shifts are necessary because exceptional academic ability and motivation are not enough to get Black males from their first year in a science, technology, education, and mathematics "STEM" major to a bachelor's degree in science and engineering. The conclusions focus on the balance of truth-slippery slopes concerning the confluence of science teachers' further ado and Black male students' theories, methods, and values that position their academic achievement in science and engineering majors.

  18. THE BITTER TRUTH: A COMPARATIVE ANALYSIS OF BLACK MALE AND BLACK FEMALE ENTREPRENEURS

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    SHERRHONDA R. GIBBS

    2014-01-01

    The paper examines variables stated to be central to entrepreneurial success and reports differences between black male and black female entrepreneurs. Variables studied include task-specific efficacy, firm performance and opportunity recognition. Using a sample of 85 males and 58 females, results indicated that although black male and female entrepreneurs are somewhat similar in terms of business environment and demographics (e.g., education levels, years of business industry experience, lik...

  19. Engaging Black Males on Their Own Terms: What Schools Can Learn from Black Males Who Produce Hip-Hop

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    Irby, Decoteau J.; Petchauer, Emery; Kirkland, David

    2013-01-01

    Education scholars and practitioners have much to learn about engagement and motivation of Black males by directing their inquiries to more organic sites of hip-hop cultural production outside of schools. One such site is the hip-hop's informal labor economy where Black males engage in earning money through hip-hop cultural production. Labor…

  20. A Demographic Analysis of Suicide among Black Males.

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    Davis, Robert

    Although statistical patterns associated with suicide suggest that blacks should be the least likely to commit suicide, black men between the ages of 18-25 do not conform to this pattern. The suicide rate for black males in this age group, which approximates and sometimes surpasses the rate for their white male cohorts, is more than three times…

  1. Communities for and with Black Male Students

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    Jett, Christopher C.; Stinson, David W.; Williams, Brian A.

    2015-01-01

    The social and educational status of black male youth in the United States has been receiving increasing attention. In February 2014, President Barack Obama announced a new national initiative--My Brother's Keeper--for helping black boys and male youth or, to speak more generally, boys and young men of color, to "stay on track; providing the…

  2. Culturally Responsive Social Skills Instruction for Adolescent Black Males

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    Robinson-Ervin, Porsha; Cartledge, Gwendolyn; Keyes, Starr

    2011-01-01

    The cultural disconnect between black males and the school environment has been correlated with poor academic achievement and high discipline rates for Black males. Instructional strategies that draw upon the learner?s cultural background hold promise as one means for intervention. This paper addresses the social skills needs of black adolescent…

  3. Empowering Young Black Males--III: A Systematic Modular Training Program for Black Male Children & Adolescents.

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    Lee, Courtland C.

    This series of five interrelated modules is an update and revision of "Saving the Native Son: Empowerment Strategies for Young Black Males (1996)." It offers specific strategies for empowering young African American males to help them achieve optimal educational and social success. Empowerment is a developmental process by which people who are…

  4. Modeling Manhood: Reimagining Black Male Identities in School

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    Givens, Jarvis R.; Nasir, Na'ilah; ross, kihana; de Royston, Maxine McKinney

    2016-01-01

    This paper examines the process by which stereotypical mainstream representations of black males (as hard, as anti-school, and as disconnected from the domestic sphere) were reimagined in all-black, all-male manhood development classes for 9th graders in urban public high schools. Findings show that instructors debunked stereotypes and created new…

  5. Anotaciones de la ecología alimentaria de monos aulladores negros en un fragmento con condiciones de hacinamiento (Balancán, Tabasco, México

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    John Aristizábal-Borja

    2011-08-01

    Full Text Available Annotations on the feeding ecology of black howler monkeys in an overcrowded fragment in Balancán, Tabasco, México. Wedescribed the feeding behavior of Central-American black howler monkey (Alouatta pigra in a fragment of less than one hectare ofhumid evergreen forest surrounded by grassland for livestock use, isolated trees and mango orchards, in the region of Balancán (Tabasco,México. Objective: To record the diet and activity of black howler monkeys in crowded conditions during the wettest month in Balancán(Tabasco, México. Methods and methods: The behavioral observations (81 h were made using the focal animal methodology withan A. pigra troop made up of three individuals (1 adult male, 1 adult female and 1 infant. Results: Feeding time represented 15.97%,rest 78% and locomotion 4.57% of total time. In the study area we recorded 14 plant species, with 10 being consumed by howlermonkeys. 55% of feeding time was devoted to the consumption of fruits, 27% to leaves, 17% to stems, and 1% to sprouts. Spondiasmombin was the tree species most consumed, with 61% of the time invested on it. Conclusion: Like other studies, we confirmed thefrugivore-folivore feeding tendency of the genus Alouatta. We provide information on the black howler monkey flexibility to live andmaintain themselves in extreme perturbation conditions, where their habitat is 0.1 ha with few tree species to use, forcing individualsto move around the ground.

  6. When top-down becomes bottom up: behaviour of hyperdense howler monkeys (Alouatta seniculus) trapped on a 0.6 ha island.

    Science.gov (United States)

    Orihuela, Gabriela; Terborgh, John; Ceballos, Natalia; Glander, Kenneth

    2014-01-01

    Predators are a ubiquitous presence in most natural environments. Opportunities to contrast the behaviour of a species in the presence and absence of predators are thus rare. Here we report on the behaviour of howler monkey groups living under radically different conditions on two land-bridge islands in Lago Guri, Venezuela. One group of 6 adults inhabited a 190-ha island (Danto) where they were exposed to multiple potential predators. This group, the control, occupied a home range of 23 ha and contested access to food resources with neighbouring groups in typical fashion. The second group, containing 6 adults, was isolated on a remote, predator-free 0.6 ha islet (Iguana) offering limited food resources. Howlers living on the large island moved, fed and rested in a coherent group, frequently engaged in affiliative activities, rarely displayed agonistic behaviour and maintained intergroup spacing through howling. In contrast, the howlers on Iguana showed repulsion, as individuals spent most of their time spaced widely around the perimeter of the island. Iguana howlers rarely engaged in affiliative behaviour, often chased or fought with one another and were not observed to howl. These behaviors are interpreted as adjustments to the unrelenting deprivation associated with bottom-up limitation in a predator-free environment.

  7. When top-down becomes bottom up: behaviour of hyperdense howler monkeys (Alouatta seniculus trapped on a 0.6 ha island.

    Directory of Open Access Journals (Sweden)

    Gabriela Orihuela

    Full Text Available Predators are a ubiquitous presence in most natural environments. Opportunities to contrast the behaviour of a species in the presence and absence of predators are thus rare. Here we report on the behaviour of howler monkey groups living under radically different conditions on two land-bridge islands in Lago Guri, Venezuela. One group of 6 adults inhabited a 190-ha island (Danto where they were exposed to multiple potential predators. This group, the control, occupied a home range of 23 ha and contested access to food resources with neighbouring groups in typical fashion. The second group, containing 6 adults, was isolated on a remote, predator-free 0.6 ha islet (Iguana offering limited food resources. Howlers living on the large island moved, fed and rested in a coherent group, frequently engaged in affiliative activities, rarely displayed agonistic behaviour and maintained intergroup spacing through howling. In contrast, the howlers on Iguana showed repulsion, as individuals spent most of their time spaced widely around the perimeter of the island. Iguana howlers rarely engaged in affiliative behaviour, often chased or fought with one another and were not observed to howl. These behaviors are interpreted as adjustments to the unrelenting deprivation associated with bottom-up limitation in a predator-free environment.

  8. Black Males and Television: New Images Versus Old Stereotypes.

    Science.gov (United States)

    Douglas, Robert L.

    1987-01-01

    This paper focuses on historic portrayal of black males in service and support roles in the media and their relation to social reality. Both television and films use glamorous sophisticated trappings seemingly to enhance the image of black males, but the personalities of the characters they play remain stereotypic. (VM)

  9. Touchdowns and Honor Societies: Expanding the Focus of Black Male Excellence

    Science.gov (United States)

    Morris, Jerome E.; Adeyemo, Adeoye O.

    2012-01-01

    The athletic/academic paradox for black males is historically rooted in rank-and-file notions of black people primarily as workers rather than thinkers. Policymakers, educators, and administrators should think more deeply about how societal perceptions of black males as "natural" athletes, rather than intelligent students adversely influences how…

  10. Young, Black, and Sentenced To Die: Black Males and the Death Penalty.

    Science.gov (United States)

    Joseph, Janice

    1996-01-01

    Explores the death penalty as imposed on young black males in the United States and examines the disparity in death penalty rates for homicides with black offenders and white victims. States continue to impose the death penalty rather than viewing youth violence as a failure of the social system. (SLD)

  11. Black Otherfathering in the Educational Experiences of Black Males in a Single-Sex Urban High School

    Science.gov (United States)

    Brooms, Derrick R.

    2017-01-01

    Background/Context: A good deal of research has been written about the problems and challenges facing Black male youth in their educational endeavors, ranging from academic performances, aspirations, and outcomes to student-teacher relationships, social experiences, and identity development. Statements calling for more Black male teachers abound…

  12. Teacher Education and Black Male Students in the United States

    Directory of Open Access Journals (Sweden)

    H. Richard Milner

    2013-10-01

    Full Text Available Teacher education programs in the United States (U.S. struggle to prepare teachers to meet the complex needs of elementary and secondary students in public schools - especially those of color, those living in poverty, and those whose first language is not English. In this article, we argue for focused attention on preparing educators to teach African American male students as these students face particular institutional challenges in successfully navigating the U.S. public school system. Drawing from the significant body of research on teacher education and teacher learning for equity and social justice, four Black teacher educators discuss challenges they have faced in classes designed to prepare teachers to teach Black male students. Through an analysis of commonalities in their experiences, they propose means for teacher educators to foster greater understandings of the heterogeneity found among Black male students so that teachers can craft more responsive and responsible educational experiences for Black males.

  13. Treating Mental Illness among Diabetic Black Male Adolescents: A Review

    Science.gov (United States)

    Banks, Andrae; Fields, Lashawnda; O'Dwyer, Curtis; Scott, Marquisha Lawrence; Joe, Sean

    2018-01-01

    Objective: To examine randomized controlled trials (RCTs) for treatment evidence for Black male adolescents suffering from comorbid mental illness and diabetes mellitus. Method: A review of the studies published in English-language journals was conducted. Results: We found no RCT focused on Black males with diabetes mellitus Type 2 (DMT2).…

  14. Adolescent Black Males' Drug Trafficking and Addiction: Three Theoretical Perspectives.

    Science.gov (United States)

    Moore, Sharon E.

    1995-01-01

    Explains the incidence and nature of drug trafficking and chemical dependency among adolescent black males. The paper also discusses the social science theories of Emile Durkheim, Karl Marx, and Molefi Asante to better understand the behaviors, and the consequences of those behaviors, of young black males who participate in drug trafficking. (GR)

  15. Cascading impacts of anthropogenically driven habitat loss: deforestation, flooding, and possible lead poisoning in howler monkeys (Alouatta pigra).

    Science.gov (United States)

    Serio-Silva, Juan Carlos; Olguín, Eugenia J; Garcia-Feria, Luis; Tapia-Fierro, Karla; Chapman, Colin A

    2015-01-01

    To construct informed conservation plans, researchers must go beyond understanding readily apparent threats such as habitat loss and bush-meat hunting. They must predict subtle and cascading effects of anthropogenic environmental modifications. This study considered a potential cascading effect of deforestation on the howler monkeys (Alouatta pigra) of Balancán, Mexico. Deforestation intensifies flooding. Thus, we predicted that increased flooding of the Usumacinta River, which creates large bodies of water that slowly evaporate, would produce increased lead content in the soils and plants, resulting in lead exposure in the howler monkeys. The average lead levels were 18.18 ± 6.76 ppm in the soils and 5.85 ± 4.37 ppm in the plants. However, the average lead content of the hair of 13 captured howler monkeys was 24.12 ± 5.84 ppm. The lead levels in the animals were correlated with 2 of 15 blood traits (lactate dehydrogenase and total bilirubin) previously documented to be associated with exposure to lead. Our research illustrates the urgent need to set reference values indicating when adverse impacts of high environmental lead levels occur, whether anthropogenic or natural, and the need to evaluate possible cascading effects of deforestation on primates.

  16. The Sexual Stereotype of the Black Male.

    Science.gov (United States)

    Davis, Gary L.; Cross, Herbert J.

    This paper presents the results of a study to examine the existence of sexual stereotyping of black males by white college students. Subjects were 180 male and 180 female white undergraduates; they were tested in sexually segregated groups. Each read one of three types of pornographic stories (hard-core, erotic realism, or sexual fantasy). The…

  17. Playing the Game: Recruiting Black Males in Teaching

    Science.gov (United States)

    Green, Satasha L.; Martin, Darren

    2018-01-01

    The purpose of this comparative study is to ascertain the experiences and perceptions of four Black males enrolled in teacher preparation programs, one at a Predominantly Black Institution (PBI) and three at a Predominantly White Institution (PWI). Findings provide insight for Colleges of Teacher Education to understand the barriers that prevent…

  18. "The Discipline Stop": Black Male Teachers and the Politics of Urban School Discipline

    Science.gov (United States)

    Brockenbrough, Ed

    2015-01-01

    Calls for the recruitment and retention of more Black male teachers have unfolded amid popular depictions of Black men as patriarchal disciplinarians. Against that backdrop, this article investigates how 11 Black male teachers were positioned as disciplinary agents in a predominantly Black urban school district on the east coast of the United…

  19. Masculinity Identity Development and Its Relevance to Supporting Talented Black Males

    Science.gov (United States)

    Henfield, Malik S.

    2012-01-01

    The purpose of the article is to provide a brief introduction to Black male masculine identity development and relate it to the field of gifted education. It will begin with information related to identity development that is applicable to Black males. Next, the phenomenological variant of ecological systems theory (PVEST) will be explored and…

  20. Promoting the Academic Engagement and Success of Black Male Student-Athletes

    Science.gov (United States)

    Harris, Paul C.; Hines, Erik M.; Kelly, Darren D.; Williams, Derick J.; Bagley, Bethany

    2014-01-01

    The goal of this study was to provide a qualitative look at the factors associated with the academic engagement and success of Black male student-athletes in high school. The research team employed a thematic analysis to examine semi-structured interviews conducted with two successful Black male student-athletes, along with their principal,…

  1. From "brute" to "thug:" the demonization and criminalization of unarmed Black male victims in America.

    Science.gov (United States)

    Smiley, CalvinJohn; Fakunle, David

    The synonymy of Blackness with criminality is not a new phenomenon in America. Documented historical accounts have shown how myths, stereotypes, and racist ideologies led to discriminatory policies and court rulings that fueled racial violence in a post-Reconstruction era and has culminated in the exponential increase of Black male incarceration today. Misconceptions and prejudices manufactured and disseminated through various channels such as the media included references to a " brute " image of Black males. In the 21 st century, this negative imagery of Black males has frequently utilized the negative connotation of the terminology " thug ." In recent years, law enforcement agencies have unreasonably used deadly force on Black males allegedly considered to be "suspects" or "persons of interest." The exploitation of these often-targeted victims' criminal records, physical appearances, or misperceived attributes has been used to justify their unlawful deaths. Despite the connection between disproportionate criminality and Black masculinity, little research has been done on how unarmed Black male victims, particularly but not exclusively at the hands of law enforcement, have been posthumously criminalized. This paper investigates the historical criminalization of Black males and its connection to contemporary unarmed victims of law enforcement. Action research methodology in the data collection process is utilized to interpret how Black male victims are portrayed by traditional mass media, particularly through the use of language, in ways that marginalize and de-victimize these individuals. This study also aims to elucidate a contemporary understanding of race relations, racism, and the plight of the Black male in a 21-century "post-racial" America.

  2. Cranial shape variation in adult howler monkeys (Alouatta seniculus).

    Science.gov (United States)

    Fiorenza, Luca; Bruner, Emiliano

    2018-01-01

    Howler monkeys (genus Alouatta) display a distinctive cranial architecture characterized by airorhynchy (or retroflexion of the facial skeleton on the cranial base), a small braincase, and a posteriorly oriented foramen magnum. This configuration has been associated with distinct factors including a high folivory diet, locomotion, and the presence of a specialized vocal tract characterized by large hyoid bone. However, the morphological relationships between the facial and neurocranial blocks in Alouatta have been scarcely investigated. In this study we quantitatively analyzed the cranial shape variation in Alouatta seniculus, to evaluate possible influences and constraints in face and braincase associated with airorhynchy. We also considered the structural role of the pteric area within the cranial functional matrix. We applied landmark-based analysis and multivariate statistics to 31 adult crania, computing shape analyses based on 3D coordinates registration as well as the analysis of the Euclidean distance matrix to investigate patterns of intraspecific morphological variability. Our results suggest that allometry is the main source of variation involved in shaping cranial morphology in howlers, influencing the degree of facial proportions and braincase flattening, and generating the main sexual differences. Larger individuals are characterized by a higher degree of airorhynchy, neurocranial flattening, and expansion of the zygomatic arch. Allometric variations influence the skull as a whole, without distinct patterns for face and braincase, which behave as an integrated morphological unit. A preliminary survey on the pteric pattern suggests that the morphology of this area may be the result of variations in the vertical growth rates between face and braincase. Future studies should be dedicated to the ontogenetic series and focus on airorhynchy in terms of differential growth among distinct cranial districts. © 2017 Wiley Periodicals, Inc.

  3. Negative Social Contextual Stressors and Somatic Symptoms Among Young Black Males: An Exploratory Study

    OpenAIRE

    Scott, Lionel D.; McCoy, Henrika

    2015-01-01

    This study examines whether negative social contextual stressors were associated with somatic symptoms among young Black males (N = 74) after accounting for background and psychological characteristics. Using Cunningham and Spencer’s Black Male Experiences Measure, negative social contextual stressors connoted those experiences connected to the personal attributes, devaluation, and negative imagery of young Black males, such as being followed when entering a store or police or security guards...

  4. Cause-specific contributions to black-white differences in male mortality from 1960 to 1995

    Directory of Open Access Journals (Sweden)

    2004-04-01

    Full Text Available Between 1960 and 1995 the black-white difference in male life expectancy in the United States increased from 6.7 years to 8.2 years. To provide insights into why mortality trends have been more adverse for black men than for white men, we investigate which causes of death were principally responsible for changes in the black-white difference in male mortality at ages 15-64 between 1960 and 1995. We find that black-white differences in male mortality varied substantially during this period. The gap increased in the 1960s, declined in the 1970s, and widened in the 1980s-early 1990s. Our findings reveal considerable variation in black-white disparities by cause of death and by age, as well as changes in the relative importance of various causes of death to the black-white male mortality disparity over time. The results suggest that consequences of black-white differences in socioeconomic status, access to quality health care, living conditions, and residential segregation vary by cause of death.

  5. Trayvon Martin: Racial Profiling, Black Male Stigma, and Social Work Practice.

    Science.gov (United States)

    Teasley, Martell Lee; Schiele, Jerome H; Adams, Charles; Okilwa, Nathern S

    2018-01-01

    To address a critical gap in the social work literature, this article examines the deleterious effects of racial profiling as it pertains to police targeting of male African Americans. The authors use the Trayvon Martin court case to exemplify how racial profiling and black male stigma help perpetuate social inequality and injustice for black men. A racism-centered perspective is examined historically and contemporarily as a theoretical approach to understanding the role that race plays in social injustice through racial profiling. Implications for social work research design and practice aimed at increasing the social work knowledge base on racial profiling are discussed. The authors call for attention and advocacy by major social work organizations in the reduction of black male stigma and racial profiling. © 2017 National Association of Social Workers.

  6. Negative Social Contextual Stressors and Somatic Symptoms Among Young Black Males: An Exploratory Study.

    Science.gov (United States)

    Scott, Lionel D; McCoy, Henrika

    This study examines whether negative social contextual stressors were associated with somatic symptoms among young Black males ( N = 74) after accounting for background and psychological characteristics. Using Cunningham and Spencer's Black Male Experiences Measure, negative social contextual stressors connoted those experiences connected to the personal attributes, devaluation, and negative imagery of young Black males, such as being followed when entering a store or police or security guards asking them what they are doing when hanging out (e.g., in the park or playground or on the street corner). Results showed that such stressors made a unique and significant contribution to the experience of somatic symptoms. Future research directions and implications for addressing the larger societal perceptions of young Black males are discussed.

  7. Black and blue: Exploring racial bias and law enforcement in the killings of unarmed black male civilians.

    Science.gov (United States)

    Hall, Alison V; Hall, Erika V; Perry, Jamie L

    2016-04-01

    In late 2014, a series of highly publicized police killings of unarmed Black male civilians in the United States prompted large-scale social turmoil. In the current review, we dissect the psychological antecedents of these killings and explain how the nature of police work may attract officers with distinct characteristics that may make them especially well-primed for negative interactions with Black male civilians. We use media reports to contextualize the precipitating events of the social unrest as we ground our explanations in theory and empirical research from social psychology and industrial and organizational (I/O) psychology. To isolate some of the key mechanisms at play, we disentangle racial bias (e.g., stereotyping processes) from common characteristics of law enforcement agents (e.g., social dominance orientation), while also addressing the interaction between racial bias and policing. By separating the moving parts of the phenomenon, we provide a more fine-grained analysis of the factors that may have contributed to the killings. In doing so, we endeavor to more effectively identify and develop solutions to eradicate excessive use of force during interactions between "Black" (unarmed Black male civilians) and "Blue" (law enforcement). (c) 2016 APA, all rights reserved).

  8. Understanding Black Male Student Athletes' Experiences at a Historically Black College/University: A Mixed Methods Approach

    Science.gov (United States)

    Cooper, Joseph N.; Hall, Jori

    2016-01-01

    The purpose of this article is to describe how a mixed methods approach was employed to acquire a better understanding of Black male student athletes' experiences at a historically Black college/university in the southeastern United States. A concurrent triangulation design was incorporated to allow different data sources to be collected and…

  9. Transitioning from Elementary School to Middle School: The Ecology of Black Males' Behavior

    Science.gov (United States)

    Mundy, Alma Christienne

    2014-01-01

    The purpose of this mixed method study is to explain the ecology Black males experience as they transition from elementary school to middle school in terms of behavior. The Black male graduation rate is well below 50% nationally (Orfield, Losen, Wald, & Swanson, 2004; Schott Foundation for Public Education, 2010). Graduating from high school…

  10. Research Concerns, Cautions and Considerations on Black Males in a "Post-Racial" Society

    Science.gov (United States)

    Howard, Tyrone C.; Flennaugh, Terry

    2011-01-01

    Black males continue to be one of the most academically marginalized groups of students in US schools, and undoubtedly the role of race and racism has largely influenced these experiences. The paradox of the underperformance of Black males has been the election of President Obama in 2008. The Obama election has led some to question whether or not…

  11. Attitudes about Male-Female Relations among Black Adolescents.

    Science.gov (United States)

    Rubin, Roger H.

    1981-01-01

    Examines the relationship of family structure, peer group affiliation, social class, and sex with five dependent variables concerned with attitudes toward dating values, marriage, romanticism, premarital pregnancy, and premarital sexual permissiveness among 85 rural, Black adolescent males and females. Findings suggest general community norms and…

  12. Healthcare Providers' Formative Experiences with Race and Black Male Patients in Urban Hospital Environments.

    Science.gov (United States)

    Plaisime, Marie V; Malebranche, David J; Davis, Andrea L; Taylor, Jennifer A

    2017-12-01

    We explored health providers' formative personal and professional experiences with race and Black men as a way to assess their potential influence on interactions with Black male patients. Utilizing convenience sampling with snowballing techniques, we identified healthcare providers in two urban university hospitals. We compared Black and White providers' experiences based on race and level of training. We used the Gardener's Tale to conceptualize how racism may lead to racial health disparities. A semi-structured interview guide was used to conduct in-person interviews (n = 16). Using the grounded theory approach, we conducted three types of coding to examine data patterns. We found two themes reflective of personally mediated racism: (1) perception of Black males accompanied by two subthemes (a) biased care and (b) fear and discomfort and (2) cognitive dissonance. While this latter theme is more reflective of Jones's internalized racism level, we present its results because its novelty is compelling. Perception of Black males and cognitive dissonance appear to influence providers' approaches with Black male patients. This study suggests the need to develop initiatives and curricula in health professional schools that address provider racial bias. Understanding the dynamics operating in the patient-provider encounter enhances the ability to address and reduce health disparities.

  13. Gastrointestinal Parasites of Ecuadorian Mantled Howler Monkeys (Alouatta palliata aequatorialis) Based on Fecal Analysis.

    Science.gov (United States)

    Helenbrook, William D; Wade, Susan E; Shields, William M; Stehman, Stephen V; Whipps, Christopher M

    2015-06-01

    An analysis of gastrointestinal parasites of Ecuadorian mantled howler monkeys, Alouatta palliata aequatorialis, was conducted based on examination of fecal smears, flotations, and sedimentations. At least 1 type of parasite was detected in 97% of the 96 fecal samples screened across 19 howler monkey groups using these techniques. Samples averaged 3.6 parasite species per individual (±1.4 SD). Parasites included species representing genera of 2 apicomplexans: Cyclospora sp. (18% of individual samples) and Isospora sp. (3%); 6 other protozoa: Balantidium sp. (9%), Blastocystis sp. (60%), Chilomastix sp. (4%), Dientamoeba sp. (3%), Entamoeba species (56%), Iodamoeba sp. (5%); 4 nematodes: Enterobius sp. (3%), Capillaria sp. (78%), Strongyloides spp. (88%) which included 2 morphotypes, Trypanoxyuris sp. (12%); and the platyhelminth Controrchis sp. (15%). A statistically significant positive correlation was found between group size and each of 3 different estimators of parasite species richness adjusted for sampling effort (ICE: r(2) = 0.24, P = 0.05; Chao2: r(2) = 0.25, P = 0.05, and Jackknife: r(2) = 0.31, P = 0.03). Two significant associations between co-infecting parasites were identified. Based on the prevalence data, individuals infected with Balantidium sp. were more likely to also be infected with Isospora sp. (χ(2) = 6.02, P = 0.01), while individuals harboring Chilomastix sp. were less likely to have Capillaria sp. present (χ(2) = 4.03, P = 0.04).

  14. Modeling the impacts of hunting on the population dynamics of red howler monkeys (Alouatta seniculus)

    Science.gov (United States)

    Wiederholt, Ruscena; Fernandez-Duque, Eduardo; Diefenbach, Duane R.; Rudran, Rasanayagam

    2010-01-01

    Overexploitation of wildlife populations occurs across the humid tropics and is a significant threat to the long-term survival of large-bodied primates. To investigate the impacts of hunting on primates and ways to mitigate them, we developed a spatially explicit, individual-based model for a landscape that included hunted and un-hunted areas. We used the large-bodied neotropical red howler monkey (Alouatta seniculus) as our case study species because its life history characteristics make it vulnerable to hunting. We modeled the influence of different rates of harvest and proportions of landscape dedicated to un-hunted reserves on population persistence, population size, social dynamics, and hunting yields of red howler monkeys. In most scenarios, the un-hunted populations maintained a constant density regardless of hunting pressure elsewhere, and allowed the overall population to persist. Therefore, the overall population was quite resilient to extinction; only in scenarios without any un-hunted areas did the population go extinct. However, the total and hunted populations did experience large declines over 100 years under moderate and high hunting pressure. In addition, when reserve area decreased, population losses and losses per unit area increased disproportionately. Furthermore, hunting disrupted the social structure of troops. The number of male turnovers and infanticides increased in hunted populations, while birth rates decreased and exacerbated population losses due to hunting. Finally, our results indicated that when more than 55% of the landscape was harvested at high (30%) rates, hunting yields, as measured by kilograms of biomass, were less than those obtained from moderate harvest rates. Additionally, hunting yields, expressed as the number of individuals hunted/year/km2, increased in proximity to un-hunted areas, and suggested that dispersal from un-hunted areas may have contributed to hunting sustainability. These results indicate that un

  15. Through the eyes of children: Drawings as an evaluation tool for children's understanding about endangered Mexican primates.

    Science.gov (United States)

    Franquesa-Soler, Montserrat; Serio-Silva, Juan Carlos

    2017-12-01

    This study seeks to understand children's perceptions and knowledge of endangered Mexican primates. The black howler monkey (Alouatta pigra) is a charismatic species endemic to Southern Mexico, Northern Belize, and Guatemala and is a symbol of the region that fosters a sense of local pride. Therefore, it can be considered a flagship species for the forests of Southern Mexico. We evaluated the perception and knowledge that 297 Mexican elementary school children (8-10 years old) have about black howler monkeys. Specifically, we analyzed and categorized drawings made by these children based on gender, geographic context (rural or urban), and residence within or outside of Protected Areas (PAs). Student drawings were categorized into three levels of knowledge (no familiarity, basic knowledge, and sophisticated knowledge). Common misconceptions and important landscape elements for black howler conservation were gathered from these visual representations. Children were largely unfamiliar with black howlers, despite sharing the same geographical location. Knowledge was affected by context and residence, with students living within PAs more aware of black howlers than students living outside of PAs. However, overall the children showed a deep understanding of the current forest conservation situation in Southern Mexico; meaning they could be presenting a shifting baseline syndrome. The study highlights the value of assessing children's drawings as a tool that can be used to help policy makers and educational practitioners in fine-tuning educational, environmental, and marketing programs. More importantly, it is a methodology that can be applied in future research for understanding children's perceptions and knowledge about endangered species and environmental change in deciding how to improve the effectiveness of conservation messaging. © 2017 Wiley Periodicals, Inc.

  16. Racial Microaggressions: The Schooling Experiences of Black Middle-Class Males in Arizona’s Secondary Schools

    Directory of Open Access Journals (Sweden)

    Quaylan Allen

    2010-05-01

    Full Text Available The literature on Black education has often neglected significant analysis of life in schools and the experience of racism among Black middle-class students in general and Black middle-class males specifically. Moreover, the achievement gap between this population and their White counterparts in many cases is greater than the gap that exists among working-class Blacks and Whites. This study begins to document the aforementioned by illuminating the racial microaggressions experienced by Black middle-class males while in school and how their families’ usage of social and cultural capital deflect the potential negative outcomes of school racism.

  17. New Directions for Gifted Black Males Suffering from Bystander Effects: A Call for Upstanders

    Science.gov (United States)

    Grantham, Tarek C.

    2011-01-01

    An educational crisis in Black male representation in gifted programs exists, requiring a new lens through which to view problems and find solutions. Though many people observe that Black males face extraordinary barriers to successful participation in gifted programs, many stand by, watching as they are overlooked for or drop out of gifted…

  18. From Subhuman to Human Kind: Implicit Bias, Racial Memory, and Black Males in Schools and Society

    Science.gov (United States)

    Brown, Anthony L.

    2018-01-01

    This paper argues that implicit racial bias regarding black males is a manifestation of a long trajectory of Western racial memory and anti-blackness where black males have been considered subhuman or as human kinds. The author draws from theological, scientific, and social science literature to illustrate how racial discourses have historically…

  19. From “brute” to “thug:” the demonization and criminalization of unarmed Black male victims in America

    Science.gov (United States)

    Smiley, CalvinJohn; Fakunle, David

    2016-01-01

    The synonymy of Blackness with criminality is not a new phenomenon in America. Documented historical accounts have shown how myths, stereotypes, and racist ideologies led to discriminatory policies and court rulings that fueled racial violence in a post-Reconstruction era and has culminated in the exponential increase of Black male incarceration today. Misconceptions and prejudices manufactured and disseminated through various channels such as the media included references to a “brute” image of Black males. In the 21st century, this negative imagery of Black males has frequently utilized the negative connotation of the terminology “thug.” In recent years, law enforcement agencies have unreasonably used deadly force on Black males allegedly considered to be “suspects” or “persons of interest.” The exploitation of these often-targeted victims' criminal records, physical appearances, or misperceived attributes has been used to justify their unlawful deaths. Despite the connection between disproportionate criminality and Black masculinity, little research has been done on how unarmed Black male victims, particularly but not exclusively at the hands of law enforcement, have been posthumously criminalized. This paper investigates the historical criminalization of Black males and its connection to contemporary unarmed victims of law enforcement. Action research methodology in the data collection process is utilized to interpret how Black male victims are portrayed by traditional mass media, particularly through the use of language, in ways that marginalize and de-victimize these individuals. This study also aims to elucidate a contemporary understanding of race relations, racism, and the plight of the Black male in a 21-century “post-racial” America. PMID:27594778

  20. Intrinsic and Extrinsic Factors That Influence Black Males to Attend Institutions of Higher Education

    Science.gov (United States)

    Etheridge, Robert

    2013-01-01

    The purpose of this qualitative, narrative study was to explore the intrinsic and extrinsic factors that motivated Black males to attend institutions of higher education. The Self-determination theory and the Integrated Model for Educational Choice formed the theoretical framework for this study. Eight Black males who were between the ages of 18…

  1. Health risk behaviors of black male college students: seat belt use, smoking, and obesity status.

    Science.gov (United States)

    Ajibade, Phoebe Butler

    2010-01-01

    This paper examined health behaviors (seatbelt use, tobacco use, and obesity status) of 127 black male college students using data obtained from the National College Health Risk Behavior Survey. The majority of the participants were freshmen and sophomores (70%), full time students (95%), and lived on campus (85%). The results indicated that black males often failed to use seatbelts while riding as a passenger (69%) or driving (48%). Although 15% of the students smoked, 1/3 of the smokers began smoking during college. Approximately 50% of the students were overweight or obese; among students attempting to lose weight, exercise versus nutrient intake was used as a means to lose weight. The study recommendations included the need to increase educational efforts to alert black males to their risks for a premature death, and to provide programming/mentoring initiatives to assist males in dealing with stress and discrimination that may impact their health-related decision making. The implications of this study suggest that even educated black males are at risk for premature disease and disability as a result of their health behaviors.

  2. Primatology in southern Brazil: a transdisciplinary approach to the conservation of the brown-howler-monkey Alouatta guariba clamitans (Primates, Atelidae

    Directory of Open Access Journals (Sweden)

    Leandro Jerusalinsky

    2010-12-01

    Full Text Available Human interventions in natural environments are the main cause of biodiversity loss worldwide. The situation is not different in southern Brazil, home of five primate species. Although some earlier studies exist, studies on the primates of this region began to be consistently carried out in the 1980s and have continued since then. In addition to important initiatives to study and protect the highly endangered Leontopithecus caissara Lorrini & Persson, 1990 and Brachyteles arachnoides E. Geoffroy, 1806, other species, including locally threatened ones, have been the focus of research, management, and protection initiatives. Since 1993, the urban monkeys program (PMU, Programa Macacos Urbanos has surveyed the distribution and assessed threats to populations of Alouatta guariba clamitans (Cabrera, 1940 in Porto Alegre and vicinity. PMU has developed conservation strategies on four fronts: (1 scientific research on biology and ecology, providing basic knowledge to support all other activities of the group; (2 conservation education, which emphasizes educational presentations and long-term projects in schools near howler populations, based on the flagship species approach; (3 management, analyzing conflicts involving howlers and human communities, focusing on mitigating these problems and on appropriate relocation of injured or at-risk individuals; and finally, (4 Public Policies aimed at reducing and/or preventing the impact of urban expansion, contributing to create protected areas and to strengthen environmental laws. These different approaches have contributed to protect howler monkey populations over the short term, indicating that working collectively and acting on diversified and interrelated fronts are essential to achieve conservation goals. The synergistic results of these approaches and their relationship to the prospects for primatology in southern Brazil are presented in this review.

  3. Darker Skin Tone Increases Perceived Discrimination among Male but Not Female Caribbean Black Youth

    Directory of Open Access Journals (Sweden)

    Shervin Assari

    2017-12-01

    Full Text Available Background: Among most minority groups, males seem to report higher levels of exposure and vulnerability to racial discrimination. Although darker skin tone may increase exposure to racial discrimination, it is yet unknown whether skin tone similarly influences perceived discrimination among male and female Caribbean Black youth. Objective: The current cross-sectional study tests the role of gender on the effects of skin tone on perceived discrimination among Caribbean Black youth. Methods: Data came from the National Survey of American Life-Adolescent Supplement (NSAL-A, 2003–2004, which included 360 Caribbean Black youth (ages 13 to 17. Demographic factors (age and gender, socioeconomic status (SES; family income, income to needs ratio, and subjective SES, skin tone, and perceived everyday discrimination were measured. Linear regressions were used for data analysis. Results: In the pooled sample, darker skin tone was associated with higher levels of perceived discrimination among Caribbean Black youth (b = 0.48; 95% Confidence Interval (CI = 0.07–0.89. A significant interaction was found between gender and skin tone (b = 1.17; 95% CI = 0.49–1.86, suggesting a larger effect of skin tone on perceived discrimination for males than females. In stratified models, darker skin tone was associated with more perceived discrimination for males (b = 1.20; 95% CI = 0.69–0.72 but not females (b = 0.06; 95% CI = −0.42–0.55. Conclusion: Similar to the literature documenting male gender as a vulnerability factor to the effects of racial discrimination, we found that male but not female Caribbean Black youth with darker skin tones perceive more discrimination.

  4. The Destruction of the Young Black Male: The Impact of Popular Culture and Organized Sports.

    Science.gov (United States)

    Gaston, John C.

    1986-01-01

    Argues that the negative aspects of popular culture and organized sports in American society contribute to the economic, psychological, and social destruction of the Black male. The media nurtures unrealistic fantasies in young Black males, preventing them from acquiring the education and skills necessary to participate in the mainstream. (ETS)

  5. Dirt on My Record: Rethinking Disciplinary Practices in an All-Black, All-Male Alternative Class

    Science.gov (United States)

    Nasir, Na'Ilah Suad; Ross, Kihana Miraya; McKinney de Royston, Maxine; Givens, Jarvis; Bryant, Jalessa N.

    2013-01-01

    In this empirical study, the authors draw on classroom observations and interviews with twenty-three Black male ninth graders in an urban district to focus on the nature of disciplinary practices in an all-Black, all-male manhood development class. While scholars have identified the "discipline gap" as a salient aspect of the experience…

  6. Is perceived parental monitoring associated with sexual risk behaviors of young Black males?

    Directory of Open Access Journals (Sweden)

    Richard Crosby

    2015-01-01

    Full Text Available This study determined whether perceived parental monitoring is associated with any of twelve selected outcomes related to sexual risk behaviors of young Black males. Recruitment occurred in clinics diagnosing and treating sexually transmitted infections. Young Black males living with a parent or guardian (N = 324 were administered a 9-item scale assessing level of perceived parental monitoring. The obtained range was 10–45, with higher scores representing more frequent monitoring. The mean was 29.3 (sd = 7.0. Eight of the twelve outcomes had significant associations with perceived parental monitoring (all in a direction indicating a protective effect. Of these eight, five retained significance in age-adjusted models were ever causing a pregnancy, discussing pregnancy prevention, safer sex, and condom use with sex partners, and using a condom during the last act of penile–vaginal sex. Monitoring by a parent figure may be partly protective against conceiving a pregnancy for Black males 15–23 years of age.

  7. Black males' self-perceptions of academic ability and gifted potential in advanced science classes

    Science.gov (United States)

    Rascoe, Barbara; Monroe Atwater, Mary

    2005-10-01

    The purpose of this research effort was to examine Black male students' self-perceptions of academic ability and gifted potential in science. The purposeful sample consisted of nine Black males between the ages of 14 and 18 years. Four categories of self-perceptions of academic ability and gifted potential emerged from the data. These included: (a) gifted high achievers; (b) gifted could do better high achievers; (c) gifted could do better situational nonachievers; and (d) gifted could do better underachievers. Science teachers' influences that referenced participants' academic achievement pointed to validation. Participants' perceptions regarding how science teachers' influenced their academic performance focused on science teachers' content knowledge. Power dynamics germane to Black male participants' value or worth that directed their efforts in science learning environments are discussed. Implications are posited for science teaching, science education programs, and future research. This research endeavor was based on two premises. The first premise is that Black males' self-perceptions of academic ability affect their science academic achievement. The second premise is that, given parental, peer, and community influences, science teachers have considerable influence on students' self-perceptions of academic ability. However, the focus of this research was not on parental influences, peer influences, or any potential influences that participants' communities may have on their academic achievement.

  8. "STEMulating" success factors: An investigation of the academic talents of successful Black male college graduates from STEM programs

    Science.gov (United States)

    Hendricks, Jill T.

    This phenomenological research study explored the contributing factors experienced by Black males that epitomized their academic success in a STEM (Science, Technology, Engineering, and Mathematics) area of study. During this investigative project, eleven Black male students were interviewed to determine how they were able to successfully navigate and complete a STEM degree. The data was collected through a qualitative inquiry, which involved interviewing students and collecting the data and organizing their perspectives into common themes. The principal findings in this study suggest that Black males can excel when primary influential people establish high expectations and believe and encourage Black males to succeed by providing the essential educational support models requisite to warrant success; the Black male maintains and affirms a self-assured self-worth in himself; the Black male is exposed to these fields and professions early on in their educational quest to enable them to witness first hand powerful and productive opportunities and pathways to academic success; exposure to other Black successful male role models who can mentor and show positive proof that with effort, these fields can become a reality; increase in academic motivation and recommendations from educators and counselors who direct and guide students into and away from these rigorous career fields. An analysis of the students' individual stories gave a revealing look into the pathways of their consciousness, emotional growth, and perspectives about being a successful STEM major. This kind of insight can be a constructive diagnostic tool for students, educators, counselors, and administrators who want to motivate and influence future students to major in STEM fields of study.

  9. Using Our Voices, Losing Our Bodies: Michael Brown, Trayvon Martin, and the Spirit Murders of Black Male Professors in the Academy

    Science.gov (United States)

    Johnson, Lamar; Bryan, Nathaniel

    2017-01-01

    The recent deaths of Michael Brown, Trayvon Martin, and other Black males have generated new civil rights urgencies in Black communities and spirited academic discourses in higher education regarding the educational and social plight of Black males in America. Connecting the deaths of Black males to our lived experiences in the academy, we use a…

  10. Attitudes, Knowledge, and Behavior Regarding Condom Use in Urban Black Adolescent Males.

    Science.gov (United States)

    Wilson, Michele D.; And Others

    1994-01-01

    Examined male adolescent behavior, attitudes, and knowledge concerning condom use. Findings from 241 sexually active black adolescent males revealed that factors associated with condom use included higher grade level, having 2 or more sexual partners in past 6 months, communication about contraception with sexual partner, desire for sexually…

  11. Multi-scale habitat use of male ruffed grouse in the Black Hills National Forest

    Science.gov (United States)

    Cassandra L. Mehls; Kent C. Jensen; Mark A. Rumble; Michael C. Wimberly

    2014-01-01

    Ruffed grouse (Bonasa umbellus) are native upland game birds and a management indicator species (MIS) for aspen (Populus tremuloides) in the Black Hills National Forest (Black Hills). Our objective was to assess resource selection of male ruffed grouse to identify the most appropriate scale to manage for aspen and ruffed grouse in the Black Hills. During spring 2007...

  12. New Possibilities: (Re)Engaging Black Male Youth within Community-Based Educational Spaces

    Science.gov (United States)

    Baldridge, Bianca J.; Hill, Marc Lamont; Davis, James Earl

    2011-01-01

    Despite the assertion that due to an Obama presidency America has become a post-racial society, Black males still face a unique social crisis. In this article, we hold that both race and gender continue to work in tandem to produce a certain set of social outcomes for young Black men in America despite this assertion. The educational, economic,…

  13. Promising Practices and Unfinished Business: Fostering Equity and Excellence for Black and Latino Males. Executive Summary

    Science.gov (United States)

    Tung, Rosann; Carlo, Vivian Dalila; Colón, Melissa; Del Razo, Jaime L.; Diamond, John B.; Raynor, Alethea Frazier; Graves, Daren; Kuttner, Paul J.; Miranda, Helena; St. Rose, Andresse

    2015-01-01

    Boston Public Schools (BPS) commissioned companion studies as part of its efforts to address achievement gaps for Black and Latino males. The first study revealed the increasing diversity of Black and Latino males and stark opportunity gaps throughout the system that contribute in large part to wide attainment gaps for these students. We…

  14. Mortality among white, black, and Hispanic male and female state prisoners, 2001–2009

    Directory of Open Access Journals (Sweden)

    Christopher Wildeman

    2016-12-01

    Full Text Available Although much research considers the relationship between imprisonment and mortality, little existing research has tested whether the short-term mortality advantage enjoyed by prisoners extends to Hispanics. We compared the mortality rates of non-Hispanic white, non-Hispanic black, and Hispanic male and female state prisoners to mortality rates in the general population using data from the Deaths in Custody Reporting Program, the National Prisoner Statistics, the National Corrections Reporting Program, and the Centers for Disease Control and Prevention. The results indicate that the mortality advantage for prisoners was greatest for black males, followed by black females, Hispanic males, white females, and white males. Hispanic female prisoners were the only group not at a mortality advantage relative to the general population, with an SMR of 1.18 [95% CI: 0.93–1.43]. Taken together, the results suggest that future research should seek to better understand the curious imprisonment–mortality relationship among Hispanic females, although given the small number of inmate deaths that happen to this group (~0.6%, this research should not detract from broader research on imprisonment and mortality. Keywords: Imprisonment, Mortality, Population health, Racial disparities

  15. The Sports Participation Effect on Educational Attainment of Black Males

    Science.gov (United States)

    Harris, Paul C.

    2014-01-01

    The purpose of this study is to explore the direct, indirect, and total effects of high school sports participation on educational attainment for Black males using the Educational Longitudinal Study (2002/2006), a large, nationally representative, database. A path analysis procedure for determining underlying causal relationships between variables…

  16. Meditating Gunrunner Speaking, Part I: A Black Male Journey Teaching in South Korea

    Science.gov (United States)

    Jackson, Johnnie

    2016-01-01

    In this article, I offer my own decolonizing counterstory of teaching as a Black American man in a teacher education program in South Korea, to purport how I was both a colonizer and the colonized, inside and outside of the classroom and the curriculum (Asher, 2010; Baszile, 2008, 2009, 2010). To further complicate matters, my Black male body did…

  17. "You Ain't My Daddy!": Black Male Teachers and the Politics of Surrogate Fatherhood

    Science.gov (United States)

    Brockenbrough, Ed

    2012-01-01

    Recent scholarship on male teachers across several national contexts has investigated the dilemmas of hegemonic masculinity for male educators while only recently beginning to examine race as a mediator of masculinity politics in teaching. Conversely, an emergent body of work on Black male teachers has centred analyses of race and culture, but has…

  18. Combating “I Hate This Stupid Book!”: Black Males and Critical Literacy

    Science.gov (United States)

    Wood, Summer; Jocius, Robin

    2013-01-01

    Too often, instruction designed to improve literacy achievement for black male readers and writers focuses on skill-based learning, ignoring cultural, social, and personal development. This article calls for the use of critical literacy strategies with African American male students, which can raise expectations for academic achievement by…

  19. Self-Esteem and Achievement of At-Risk Adolescent Black Males.

    Science.gov (United States)

    Howerton, D. Lynn; And Others

    The relationship between self-esteem and academic achievement of at-risk adolescent black males was studied for 42 students in grades 6, 7, and 8. The Coopersmith Self-Esteem Inventory (SEI) was used to provide global measures of self-esteem. School grades and scores from the Stanford Achievement Test battery were used to measure academic…

  20. Ovarian cycle of southern brown howler monkey (Alouatta guariba clamitans) through fecal progestin measurement.

    Science.gov (United States)

    Silvestre, Thiago; Zanetti, Eveline S; Duarte, José M B; Barriento, Fernando G; Hirano, Zelinda M B; Souza, Júlio C; Passos, Fernando C

    2017-01-01

    The ovarian cycle in howler monkeys (genus Alouatta) has beean investigated through several biological parameters (ranging between 16.3 and 29.5 days); however, no data exist concerning the ovarian activity of the southern brown howler monkey (Alouatta guariba clamitans). This study aimed to describe the ovarian cycle of A. g. clamitans by profiling fecal progestin concentrations. Over 20 weeks, fecal samples of eight captive adult females of A. g. clamitans were collected. The collections were made at dawn, 5 days a week, and the samples were frozen immediately following collection. Next, they were dried, pulverized and hormonal metabolites were extracted to determine progestin concentrations by enzyme immunoassay. Of the 758 samples tested, the mean concentration of fecal progestins was 2866.40 ± 470.03 ng/g of dry feces, while the mean concentration at baseline was 814.47 ± 164.36 ng/g of dry feces. Among the eight females, one showed no ovarian cyclicity and three presented periods of probable absence of cyclicity and low progestin concentrations. A mean duration of 16 ± 0.52 days was observed for the 35 cycles studied. The interluteal phase lasted 4 ± 0.37 days on average, with a mean concentration of fecal progestins of 467.98 ± 29.12 ng/g of dry feces, while the luteal phase lasted 11 ± 0.50 days, with a mean concentration of 4283.27 ± 193.31 ng/g of dry feces. Besides describing the characteristics of the ovarian cycle, possible causes for the low concentrations of fecal progestins and periods of absence of cyclicity are also discussed.

  1. Behavioral and physiological responses to subgroup size and number of people in howler monkeys inhabiting a forest fragment used for nature-based tourism.

    Science.gov (United States)

    Aguilar-Melo, Adriana R; Andresen, Ellen; Cristóbal-Azkarate, Jurgi; Arroyo-Rodríguez, Victor; Chavira, Roberto; Schondube, Jorge; Serio-Silva, Juan Carlos; Cuarón, Alfredo D

    2013-11-01

    Animals' responses to potentially threatening factors can provide important information for their conservation. Group size and human presence are potentially threatening factors to primates inhabiting small reserves used for recreation. We tested these hypotheses by evaluating behavioral and physiological responses in two groups of mantled howler monkeys (Alouatta palliata mexicana) at the "Centro Ecológico y Recreativo El Zapotal", a recreational forest reserve and zoo located in the Mexican state of Chiapas. Both groups presented fission-fusion dynamics, splitting into foraging subgroups which varied in size among, but not within days. Neither subgroup size nor number of people had an effect on fecal cortisol. Out of 16 behavioral response variables tested, the studied factors had effects on six: four were affected by subgroup size and two were affected by number of people. With increasing subgroup size, monkeys increased daily path lengths, rested less, increased foraging effort, and used more plant individuals for feeding. As the number of people increased, monkeys spent more time in lower-quality habitat, and less time engaged in social interactions. Although fecal cortisol levels were not affected by the factors studied, one of the monkey groups had almost twice the level of cortisol compared to the other group. The group with higher cortisol levels also spent significantly more time in the lower-quality habitat, compared to the other group. Our results suggest that particular behavioral adjustments might allow howler monkeys at El Zapotal to avoid physiological stress due to subgroup size and number of people. However, the fact that one of the monkey groups is showing increased cortisol levels may be interpreted as a warning sign, indicating that an adjustment threshold is being reached, at least for part of the howler monkey population in this forest fragment. © 2013 Wiley Periodicals, Inc.

  2. The effect of survivalism--self-expressionism culture on black male suicide acceptability: a cross-national analysis.

    Science.gov (United States)

    Stack, Steven; Kposowa, Augustine J

    2011-04-01

    Cultural explanations of black suicide have focused on the US and stressed religiosity as a protective factor. This paper adds to this literature by (1) expanding the analysis of the impact of religiosity on black suicide to 10 nations, and (2) assessing the extent to which a broader cultural construct (self expressionism) affects black suicide acceptability. Data are from Wave 4 of the World Values Surveys 1991-2001 and refer to 3580 black males nested in ten countries. A hierarchical linear regression model determined that religiosity predicted black suicide acceptability across ten nations. Self expressionism was positively associated with individual level suicide acceptability. Further, a cross-level interaction was found wherein individual level and societal level self expressionism combined to affect suicide acceptability. The variability in suicide acceptability among black males is predicted, in part, by both individual and group levels of adherence to values contained in a major cultural axis of nations: self expressionism. These new found associations compliment the impact of a standard predictor, religiosity, on suicide acceptability. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Lianas as a food resource for brown howlers (Alouatta guariba) and southern muriquis (Brachyteles arachnoides) in a forest fragment

    OpenAIRE

    M. M. Martins

    2009-01-01

    Lianas as a food resource for brown howlers (Alouatta guariba) and southern muriquis (Brachyteles arachnoides) in a forest fragment.— Lianas, woody vines, are abundant and diverse in tropical forests, but their relative contribution as a source of food for herbivores has been neglected. I compared feeding rates on lianas and trees of two sympatric primates, A. guariba and B. arachnoides, in Southeastern Brazil. Availability of liana foods was gathered in parallel with primate behavioral data ...

  4. A chasm between injury and care: experiences of black male victims of violence.

    Science.gov (United States)

    Liebschutz, Jane; Schwartz, Sonia; Hoyte, Joel; Conoscenti, Lauren; Christian, Anthony B; Muhammad, Leroy; Harper, Derrick; James, Thea

    2010-12-01

    Despite higher rates of stabbing and shooting violence among black men, healthcare systems have not demonstrated an efficacious response to these patients. This study describes challenges and promotive factors for engaging black male violence victims of violence with medical and mental healthcare. Black male victims of stabbings and shootings were recruited through fliers and word of mouth, and were interviewed individually (n = 12) or in pairs (n = 4) using a semistructured guide. A racially diverse multidisciplinary team analyzed the data using Grounded Theory methods. Challenges to engagement with healthcare included the following: (1) Disconnect in the aftermath; e.g. participants reported not realizing they were seriously injured ("just a scratch" "poke"), were disoriented ("did not know where I was"), or were consumed with anger. (2) Institutional mistrust: blurred lines between healthcare and police, money-motivated care. (3) Foreshortened future: expectations they would die young. (4) Self-reliance: fix mental and substance abuse issues on their own. (5) Logistical issues: postinjury mental health symptoms, disability, and safety concerns created structural barriers to recovery and engagement with healthcare. Promotive factors included the following: (1) desire professionalism, open personality, and shared experience from clinicians; (2) turning points: injury or birth of a child serve as a "wake up call"; and (3) positive people, future-oriented friends and family. For black male violence victims, medical treatment did not address circumstances of and reactions to injury. Policies delineating boundaries between medical care and law enforcement and addressing postinjury mental health symptoms, disability, and safety concerns may improve the recovery process.

  5. Scripted Curriculum: What Movies Teach about Dis/ability and Black Males

    Science.gov (United States)

    Agosto, Vonzell

    2014-01-01

    Background/Context: Tropes of dis/ability in the movies and master-narratives of Black males in education and society are typically treated in isolation. Furthermore, education research on Hollywood movies has typically focused on portrayals of schools, principals, and teachers even though education professionals are exposed to a broader range of…

  6. Ejaculate of sneaker males is pheromonally inconspicuous in the black goby, Gobius niger (Teleostei, Gobiidae).

    Science.gov (United States)

    Locatello, L; Mazzoldi, C; Rasotto, M B

    2002-11-01

    The black goby, Gobius niger, shows alternative male mating tactics, i.e., parental and sneaker males. Males release a sexual pheromone that attracts females and stimulates aggressive displays in males. This pheromone is produced by the mesorchial gland, a structure well developed in parental males but markedly undeveloped in sneakers. We measured the behavioral response of parental males to the ejaculates of males performing different reproductive tactics. Parental males reacted to the ejaculate of other parental males, with stereotypic aggressive behaviors, but not to the ejaculate of sneakers; consequently sneaker male ejaculate appears to be pheromonally inconspicuous. Copyright 2002 Wiley-Liss, Inc.

  7. Academic and Career Advancement for Black Male Athletes at NCAA Division I Institutions

    Science.gov (United States)

    Baker, Ashley R.; Hawkins, Billy J.

    2016-01-01

    This chapter examines the structural arrangements and challenges many Black male athletes encounter as a result of their use of sport for upward social mobility. Recommendations to enhance their preparation and advancement are provided.

  8. Black Generation Y male students' fashion consciousness and need for uniqueness / Matebello Dieketseng Bethsheba Motale

    OpenAIRE

    Motale, Matebello Dieketseng Bethsheba

    2015-01-01

    While there have been numerous studies directed at addressing the female Generation Y cohort’s fashion consumption patterns, there is a dearth of published research focused on male consumer fashion conscious behaviour, especially not that of the African Generation Y (hereafter referred to as black Generation Y) males. There are global indications that contemporary males are engaging in fashion apparel shopping more frequently than ever before. Moreover, unlike past generations, today’s male c...

  9. New Entamoeba group in howler monkeys (Alouatta spp.) associated with parasites of reptiles.

    Science.gov (United States)

    Villanueva-García, Claudia; Gordillo-Chávez, Elías José; Baños-Ojeda, Carlos; Rendón-Franco, Emilio; Muñoz-García, Claudia Irais; Carrero, Julio César; Córdoba-Aguilar, Alex; Maravilla, Pablo; Galian, José; Martínez-Hernández, Fernando; Villalobos, Guiehdani

    2017-08-01

    Our knowledge of the parasite species present in wildlife hosts is incomplete. Protozoans such as amoebae of the genus Entamoeba infect a large variety of vertebrate species, including NHPs. However, traditionally, their identification has been accomplished through microscopic evaluation; therefore, amoeba species have not always been identified correctly. We searched for Entamoeba spp. using a fragment of the small subunit rDNA in free-ranging howler monkeys (Alouatta palliata and A. pigra) from southeast Mexico. One hundred fifty five samples were collected, with 46 from A. palliata and 109 from A. pigra and 8 of the total samples were positive. We detected a new clade of Entamoeba, which was separated from other described species but closer to E. insolita, as well as an unnamed sequence typically found in iguana species with low shared identity values (reptiles.

  10. To Be Alone or in a Group: An Exploration into How the School-Based Experiences Differ for Black Male Teachers across One Urban School District

    Science.gov (United States)

    Bristol, Travis J.

    2018-01-01

    One urban district administered the Black Male Teacher Environment Survey (BMTES) to each of its Black male teachers to measure their school-based experiences. This article highlights descriptive statistics from the 86 Black male teacher respondents. Findings suggest that participants' background characteristics and school-based experiences varied…

  11. The Male Initiative on Leadership and Excellence (MILE) and Its Impact on Retention and Persistence of Black Men at Historically Black Colleges and Universities (HBCUs)

    Science.gov (United States)

    Palmer, Robert T.; Maramba, Dina C.; Dancy, T. Elon

    2013-01-01

    A strong body of research has documented the supportive environments of historically Black colleges and universities (HBCUs) and their impact on facilitating student success. Notwithstanding the consistency of these findings, recent reports and empirical research have highlighted the problems that HBCUs are experiencing with Black male enrollment,…

  12. Building a Species Conservation Strategy for the brown howler monkey (Alouatta guariba clamitans) in Argentina in the context of yellow fever outbreaks

    OpenAIRE

    Agostini, Ilaria; Holzmann, Ingrid; Di Bitetti, Mario Santiago; Oklander, Luciana Inés; Kowalewski, Martín M.; Beldomenico, Pablo Martín; Goenaga, Silvina; Martinez, Mariela; Moreno, Eduardo S.; Lestani, Eduardo; Desbiez, Arnaud L.J.; Miller, Philip

    2017-01-01

    The brown howler monkey (Alouatta guariba clamitans) is endemic to South America’s Atlantic Forest, with a small population extending into the northern portion of Misiones province in northeastern Argentina. In 2012, the species was classified as Critically Endangered in Argentina due to its highly restricted distribution, low population density and dramatic declines from recent Yellow Fever outbreaks. In March 2013, we organized an international workshop in Misiones to evaluate population st...

  13. Black Male Graduation Rates in Community Colleges: Do Institutional Characteristics Make a Difference

    Science.gov (United States)

    Vasquez Urias, Marissa; Wood, J. Luke

    2014-01-01

    The purpose of this study was to investigate Black male graduation rates in public two-year, degree-granting institutions. Specifically, the researchers were interested in determining the influence (if any) of select institutional characteristics (e.g., attendance intensity, degree of urbanization, geographic region, institutional size) on…

  14. What Works for Adolescent Black Males at Risk of Suicide: A Review

    Science.gov (United States)

    Joe, Sean; Scott, Marquisha Lawrence; Banks, Andrae

    2018-01-01

    We reviewed the controlled studies that report outcome findings for Black adolescent males 24 years of age and younger at risk of suicide. Our review identified 48 articles published from 2000 to 2015, 33 that met our initial criteria for full-text articles review, resulting in 6 that met all inclusion criteria. We sought to understand what works…

  15. Popular Visual Images and the (Mis)Reading of Black Male Youth: A Case for Racial Literacy in Urban Preservice Teacher Education

    Science.gov (United States)

    Sealey-Ruiz, Yolanda; Greene, Perry

    2015-01-01

    In the majority of public schools across the nation, Black male youth are undergoing what can be deemed as "educational genocide"--the killing off of any chances for an equitable education. This dramatically decreases opportunities for Black male youth to develop into fully participating citizens in a democratic society. In many ways,…

  16. After-School Programs: A Resource for Young Black Males and Other Urban Youth

    Science.gov (United States)

    Woodland, Malcolm H.

    2016-01-01

    While after-school programs are plentiful, they are often developed arbitrarily with little attention given to theoretical underpinnings that may inform program interventions. In this article, after-school programs are situated in resilience theory as protective factors, which encourage resilience among young Black males and other urban youth. The…

  17. From sneaker to parental male: change of reproductive traits in the black goby, Gobius niger (Teleostei, Gobiidae).

    Science.gov (United States)

    Immler, Simone; Mazzoldi, Carlotta; Rasotto, Maria Berica

    2004-02-01

    This study focuses on the consequences of the switch of tactic from parasitic to parental male in the black goby, Gobius niger (Teleostei: Gobiidae), a species showing two alternative male mating tactics. Older and larger males defend nests, court, and perform parental care on eggs, while younger and smaller ones behave as parasites, sneaking into nests while spawning occurs. Males adopting different tactics are known to present differences in primary and secondary sex traits. The social context of sneaker males was manipulated to induce a tactic switch. Sneakers were kept under two different experimental treatments with or without a female, and under exclusion of male-male competition. Males changed tactics, courting females, spawning, and performing parental care. All males showed substantial changes in primary sexual traits, such as a reduction in gonadal development and an increase in the investment in accessory structures. The experimental groups differed in the functionality of gonads and accessory organs and in the development of the secondary sex traits. These results demonstrate that the moment of switching is not genetically fixed in the black goby. Sneaker males are able to quickly reallocate energy in primary and secondary sex traits, in accordance with the adopted tactic. Several aspects of this flexible reproductive pattern resemble the socially controlled sex change found in sequential hermaphrodites. Copyright 2004 Wiley-Liss, Inc.

  18. The Death of Imhotep: A Hermeneutical Framework for Understanding the Lack of Black Males in STEM Fields

    Science.gov (United States)

    Mocombe, Paul C.

    2018-01-01

    In Afrocentric circles in the United States, ancient Kemetic (Egyptian) scientist Imhotep is considered the Black father of medicine. In this article, I use his name in the title as an allusion to highlight the lack of Black males matriculating in science, technology, engineering, and mathematics (STEM) programs or fields in the United States. The…

  19. Testosterone affects song modulation during simulated territorial intrusions in male black redstarts (Phoenicurus ochruros.

    Directory of Open Access Journals (Sweden)

    Beate Apfelbeck

    Full Text Available Although it has been suggested that testosterone plays an important role in resource allocation for competitive behavior, details of the interplay between testosterone, territorial aggression and signal plasticity are largely unknown. Therefore, we investigated if testosterone acts specifically on signals that communicate the motivation or ability of individuals to engage in competitive situations in a natural context. We studied the black redstart, a territorial songbird species, during two different life-cycle stages, the early breeding phase in spring and the non-breeding phase in fall. Male territory holders were implanted with the androgen receptor blocker flutamide (Flut and the aromatase inhibitor letrozole (Let to inhibit the action of testosterone and its estrogenic metabolites. Controls received a placebo treatment. Three days after implantation birds were challenged with a simulated territorial intrusion (STI. Song was recorded before, during and after the challenge. In spring, both treatment groups increased the number of elements sung in parts of their song in response to the STI. However, Flut/Let-implanted males reacted to the STI with a decreased maximum acoustic frequency of one song part, while placebo-implanted males did not. Instead, placebo-implanted males sang the atonal part of their song with a broader frequency range. Furthermore, placebo-, but not Flut/Let-implanted males, sang shorter songs with shorter pauses between parts in the STIs. During simulated intrusions in fall, when testosterone levels are naturally low in this species, males of both treatment groups sang similar to Flut/Let-implanted males during breeding. The results suggest that song sung during a territorial encounter is of higher competitive value than song sung in an undisturbed situation and may, therefore, convey information about the motivation or quality of the territory holder. We conclude that testosterone facilitates context-dependent changes

  20. Do male and female black-backed woodpeckers respond differently to gaps in habitat?

    Science.gov (United States)

    Jennifer Pierson; Fred W. Allendorf; Vicki Saab; Pierre Drapeau; Michael K. Schwartz

    2010-01-01

    We used population- and individual-based genetic approaches to assess barriers to movement in black-backed woodpeckers (Picoides arcticus), a fire-specialist that mainly occupies the boreal forest in North America. We tested if male and female woodpeckers exhibited the same movement patterns using both spatially implicit and explicit genetic analyses to define...

  1. Racial and gender identity among Black adolescent males: an intersectionality perspective.

    Science.gov (United States)

    Rogers, Leoandra Onnie; Scott, Marc A; Way, Niobe

    2015-01-01

    A considerable amount of social identity research has focused on race and racial identity, while gender identity, particularly among Black adolescents, remains underexamined. The current study used survey data from 183 Black adolescent males (13-16 years old) to investigate the development and relation between racial and gender identity centrality and private regard, and how these identities impact adjustment over time. It was found that dimensions of racial and gender identity were strongly correlated. Levels of racial centrality increased over time while gender centrality, and racial and gender private regard declined. In addition, racial and gender identity uniquely contributed to higher levels of psychological well-being and academic adjustment. These findings are discussed within the context of existing identity theories and intersectionality theory. © 2014 The Authors. Child Development © 2014 Society for Research in Child Development, Inc.

  2. Enhancing condom use among Black male youths: a randomized controlled trial.

    Science.gov (United States)

    Crosby, Richard A; Charnigo, Richard J; Salazar, Laura F; Pasternak, Ryan; Terrell, Ivy W; Ricks, JaNelle; Smith, Rachel V; Taylor, Stephanie N

    2014-11-01

    We tested the efficacy of a brief intervention to promote correct and consistent use of condoms among Black male youths attending sexually transmitted infection (STI) clinics in 3 southern US cities. In 2010 to 2012, we screened (n = 1102) and enrolled (n = 702) youths aged 15 to 23 years who identified as Black and reported recent (past 2 months) sexual activity and randomized them to a private, brief, interactive intervention (n = 349) or an attention-equivalent control condition (n = 353). Assessments occurred at baseline and 2 and 6 months after the intervention. At 6 months, with adjustment for age and pretest nonequivalence of the outcome variable, an estimated odds ratio (EOR) of 1.63 (95% confidence interval [CI] = 1.07, 2.49; P = .02) indicated efficacy for correct condom use. An adjusted generalized estimating equations model with both 2- and 6-month condom use variables produced an EOR of 1.49 (95% CI = 1.06, 2.08; P = .02). We did not observe significant effects on chlamydia and gonorrhea incidence. This brief intervention, delivered as part of STI clinical care, could help alleviate the disproportionate STI-HIV burden among young Black men.

  3. "To look at death another way": Black teenage males' perspectives on second-lines and regular funerals in New Orleans.

    Science.gov (United States)

    Bordere, Tashel C

    The purpose of this study was to describe how Black adolescent males understand "second-line" (musical processions) and "regular"/traditional funeral rituals in New Orleans following the violent deaths of significant persons in their lives. In-depth interviews were conducted with 10 Black males between the ages of 12 and 15 using descriptive phenomenology methodology. Findings revealed that these participants understood death as a cause for celebration, remembrance, and unity related to their experiences with the second-line ritual. Three elements of the life world of Black teenage males were descriptive of second lines, including: a) observed locations of second lines; b) dancing to good music; and c) observed messages conveyed through t-shirts. Participants provided gender-based descriptions of perceived spoken and unspoken rights in grieving at the two distinct rituals. Related to their second-line experience, the teens reflect on ways in which they wish to have their deaths ritualized.

  4. Job Attitudes of Black and White Workers: Male Blue-Collar Workers in Six Companies

    Science.gov (United States)

    Katzell, Raymond A.; And Others

    1974-01-01

    A 74-item attitude questionnaire was administered in six companies to 101 black and 87 white male blue-collar employees holding similar jobs in the same company. Differences between the two ethnic groups were not marked, both in terms of job satisfaction and in other respects. (Author)

  5. The Most Blessed Room in the City: The Influence of a Youth Development Program on Three Young Black Males

    Science.gov (United States)

    Woodland, Malcolm H.; Martin, Justin F.; Hill, R. LeRoi; Worrell, Frank C.

    2009-01-01

    The social and educational life risks associated with being a Black male in the United States are not novel concerns. However, researchers, policymakers, educators, and other stakeholders have yet to consistently identify programs and interventions that can mediate the inequities that confront young Black men. Some researchers have indicated that…

  6. Math Achievement Trajectories among Black Male Students in the Elementary- and Middle-School Years

    Science.gov (United States)

    Zilanawala, Afshin; Martin, Margary; Noguera, Pedro A.; Mincy, Ronald B.

    2018-01-01

    In this article, we analyze the variation in math achievement trajectories of Black male students to understand the different ways these students successfully or unsuccessfully navigate schools and the school characteristics that are associated with their trajectories. Using longitudinal student-level data from a large urban US city (n = 7,039),…

  7. SAAB Tackling the Black, Brown Male Crisis

    Science.gov (United States)

    Pluviose, David

    2007-01-01

    Increasingly, dropping out of high school is a one-way ticket to prison for Black men. Recent research conducted by sociologists Becky Pettit and Bruce Western indicates that 3 percent of Whites and 20 percent of Blacks born between 1965 and 1969 had served time in prison by their early thirties. The crisis among Black and Hispanic men mobilized…

  8. Negotiating Race and Sexual Orientation in the College Choice Process of Black Gay Males

    Science.gov (United States)

    Squire, Dian D.; Mobley, Steve D., Jr.

    2015-01-01

    This study explores the college choice process for Black gay males and what factors played significant roles in why they chose to attend either HBCUs or PWIs. Findings revealed that these students considered race and sexual orientation in different ways when deciding to attend either an HBCU or PWI. Implications for high school counselors and…

  9. How Does It Feel to Be a Problem? Black Male Students, Schools, and Learning in Enhancing the Knowledge Base to Disrupt Deficit Frameworks

    Science.gov (United States)

    Howard, Tyrone C.

    2013-01-01

    A close examination of a number of political, social, and economic indicators reveals the ongoing challenges of what it means to be Black and male in the United States. Many of these challenges begin at birth and persist over time. The complex, yet complicated picture of life for Black males in the United States remains a topic of study and…

  10. The number of life-history stages does not influence the androgen responsiveness to male-male interactions: sedentary and migratory black redstarts (Phoenicurus ochruros) do not elevate testosterone in response to simulated territorial intrusions.

    Science.gov (United States)

    Villavicencio, C P; Blas, J; Goymann, W

    2014-09-01

    High plasma levels of testosterone at the beginning of the breeding season adjust male physiology for mating and promote territorial behavior in birds. Conversely intra-sexual competition may elicit a temporary increase in circulating testosterone. Male black redstarts (Phoenicurus ochruros) from migratory populations show the expected increase in baseline testosterone during early breeding, but circulating testosterone levels do not change in response to male-male interactions. Because sedentary populations express fewer life-history stages they may be more flexible in timing of life-history stages and more responsive to environmental modulation of hormone concentrations. Therefore, we tested whether the androgen responsiveness to male-male interactions differs between migratory (6 life-history stages) and sedentary black redstarts (3 life-history stages) during early breeding, predicting that in contrast to migratory birds, sedentary birds would modulate testosterone in response to simulated territorial intrusions (STI). In contrast to our prediction, sedentary males did not modulate post-capture testosterone levels in response to simulated territorial intrusions. Males of both populations increased testosterone after an injection of gonadotropin releasing hormone (GnRH), demonstrating that they were capable of increasing testosterone. Interestingly, in sedentary males the GnRH injection elicited a higher testosterone response in STI males than in control males. The two populations did not differ in their behavioral response to the STIs, except that sedentary males spent less time close to the decoy. In combination with previous data from black redstarts and other socially monogamous and biparental birds our current study adds to the growing evidence that current theory regarding hormone-behavior relationship needs to be refined. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Ebony in the Ivory Tower: Examining Trends in the Socioeconomic Status, Achievement, and Self-Concept of Black, Male Freshmen

    Science.gov (United States)

    Griffin, Kimberly A.; Jayakumar, Uma M.; Jones, Malana M.; Allen, Walter R.

    2010-01-01

    Despite the educational challenges African American males face, there is a sizeable population successfully finishing high school and entering college. This study provides an overview of how a national sample of black male freshmen embodied the cognitive, social, and institutional factors related to college access between 1971 and 2004. Data…

  12. The Gender and Race Composition of Jobs and the Male/Female, White/Black Pay Gaps.

    Science.gov (United States)

    Tomaskovic-Devey, Donald

    1993-01-01

    Analysis of North Carolina survey data indicates that females' average hourly wages were 71% of males', and blacks' wages were 78% of whites'. Human capital factors (educational attainment and occupational experience) explained 31% and 3% of the racial and gender gaps, respectively. Job gender composition explained 56% of the gender gap; job…

  13. Internal/external locus of control, self-esteem, and parental verbal interaction of at-risk black male adolescents.

    Science.gov (United States)

    Enger, J M; Howerton, D L; Cobbs, C R

    1994-06-01

    We investigated the relationship between three factors--internal/external locus of control, self-esteem, and parental verbal interaction--for at-risk Black male adolescents in the United States. Forty-two male students in Grades 6, 7, and 8 who had been identified by their teachers as being at risk completed the Locus of Control Scale for Children (Nowicki & Strickland, 1973), the Self-Esteem Inventory (Coopersmith, 1967), and the Verbal Interaction Questionnaire (Blake, 1991). A moderate positive relationship found between self-esteem and parental verbal interaction was consistent with a previous finding for White high school students. A moderate negative relationship found between locus of control and self-esteem differed from a previous finding of no significant relationship for Black elementary children. A weak, yet significant, negative relationship was found between locus of control and parental verbal interaction.

  14. "Machismo," self-esteem, education and high maximum drinking among anglo, black and Mexican-American male drinkers.

    Science.gov (United States)

    Neff, J A; Prihoda, T J; Hoppe, S K

    1991-09-01

    This study seeks to clarify the relevance of machismo to patterns of high maximum drinking among male drinkers. Specifically, the study describes the psychometric properties of a newly developed 7-item machismo measure, compares levels of machismo and self-esteem for a sample of Anglo, black and Mexican-American males, and examines both main and interaction effects of machismo, self-esteem and education as predictors of alcohol use in these racial/ethnic subgroups. Logistic regression analyses document interaction between race/ethnicity, machismo, self-esteem and education, which calls into question the presumed importance of machismo as a cultural element causing heavy drinking patterns among Mexican-American males.

  15. Black Adolescent Males: Intersections Among Their Gender Role Identity and Racial Identity and Associations With Self-Concept (Global and School).

    Science.gov (United States)

    Buckley, Tamara R

    2017-09-12

    Intersectional approaches for understanding identity have gained momentum in the social sciences. Black adolescent males are often perceived as threatening, underachieving, and hypermasculine, which is reinforced through media outlets and psychological research that portray them as a monolith rather than a heterogeneous group with multiple intersecting identities. This cross-sectional study of 70 Black adolescent males between 14 and 18 years old simultaneously explores their race and gender identities and associations with self-concept (global and school). Results demonstrated that participants reported a combination of feminine and masculine gender roles, rather than hypermasculine. A canonical correlation analysis found that Black racial identity attitudes (RIAS-L) and gender roles simultaneously contributed to significant relationships with total and school self-concept. Study limitations and future directions for research and practice are discussed. © 2017 The Authors. Child Development © 2017 Society for Research in Child Development, Inc.

  16. Within-group Ethnic Differences of Black Male STEM Majors and Factors Affecting Their Persistence in College

    Directory of Open Access Journals (Sweden)

    Shane Y. Williamson

    2010-04-01

    Full Text Available The present study examined how familial and institutional factors interact with the academic experiences of a diverse group of Black males enrolled as science, technology, engineering, and mathematics (STEM majors at one university. Ogbu’s (1998 Cultural-Ecological Theory of Minority School Performance, a theoretical framework, posits that the manner by which a group achieves minority status, coupled with community and family educational values, impacts academic achievement. Immigrants, voluntary minorities, perform better academically than involuntary minorities (nonimmigrants because they are more accepting of and more likely to adapt to the White middle-class norms upon which schools in the United States are based (Ogbu, 1994, 2004. While the data overall are positive for the sample, when viewed by ethnic group, it was evident the African and Caribbean students are more academically integrated to campus than African American students. The African students, more so than any other ethnic group, are connecting, interacting, and forming relationships with faculty outside of the classroom; conversely, African American students in this study reported having the least amount of effective connections with faculty. This research study found that for the Black male STEM students in this project (a their families are a pivotal force, (b academic experiences vary across ethnicities, (c faculty mediate student success, and (d there is a lack of interactions between ethnic groups (Black Distance on campus.

  17. Social Success Skills: Black Male High School Students' Perspectives on Society and Their Media Experiences

    Science.gov (United States)

    Degand, Darnel

    2013-01-01

    This dissertation's purpose was to better understand how messages received through different cultural mediums influences the development of social success skills. Black male students were chosen as the focal participants for this year-long study because they are included among the groups whose social success skills development are thought to…

  18. Health, Trust, or “Just Understood”: Explicit and Implicit Condom Decision-Making Processes Among Black, White, and Interracial Same-Sex Male Couples

    Science.gov (United States)

    Campbell, Chadwick K.; Gómez, Anu Manchikanti; Dworkin, Shari; Wilson, Patrick A.; Grisham, Kirk; McReynolds, Jaih; Vielehr, Peter; Hoff, Colleen

    2013-01-01

    Among gay and bisexual men, primary partners are a leading source of HIV infection. Trust, intimacy, and advancements in HIV treatment may impact same-sex male couples’ decisions to engage in unprotected anal intercourse (UAI). This qualitative study explored how Black, White and interracial couples discussed, and made decisions regarding condoms. Qualitative interviews were conducted with 48 same-sex male couples in the New York and San Francisco metropolitan areas. Stratified purposive sampling was used to include Black (n = 16), White (n = 17), and interracial (Black-White) (n = 15) couples. Twenty-six couples were concordant HIV-negative and 22 were HIV-discordant. Interviews were recorded, transcribed, coded, and analyzed using a grounded theory approach. Some couples described explicit processes, which involved active discussion, while others described implicit processes, where condom-use decisions occurred without any explicit discussion. These processes also differed by race and HIV status. Black couples tended to report condom-use as “just understood.” White, HIV-discordant couples decided not to use condoms, with some identifying the HIV-positive partner’s suppressed viral load and high CD4 count as deciding factors. After an unplanned episode of UAI, White, HIV-negative couples tended to discontinue condom use while Black HIV-negative couples decided to revert to using condoms. HIV prevention efforts focused on same-sex, male couples must consider the explicit/implicit nature of condom decision-making processes. Understanding differences in these processes and considering relationship dynamics, across race and HIV status, can promote the development of innovative couple–level, HIV prevention interventions. PMID:23912774

  19. "Nothing Has Stopped Me. I Keep Going:" Black Gay Narratives

    Science.gov (United States)

    Bartone, Michael D.

    2017-01-01

    Are being Black and gay problematic in the United States? Are Black gay youth "suffering" with these two intersecting identities? Traditional Eurocentric epistemologies would have one believe that Black males, Black gay males, and gay males (liminal groups) are suffering, rarely acknowledging those successfully navigating through…

  20. African American Males Navigate Racial Microaggressions

    Science.gov (United States)

    Hotchkins, Bryan K.

    2016-01-01

    Background/Context: High school educational environments find Black males experience systemic racial microaggressions in the form of discipline policies, academic tracking and hegemonic curriculum (Allen, Scott, & Lewis, 2013). Black males in high school are more likely than their White male peers to have high school truancies and be viewed as…

  1. Sexy faces in a male paper wasp.

    Science.gov (United States)

    de Souza, André Rodrigues; Alberto Mourão Júnior, Carlos; do Nascimento, Fabio Santos; Lino-Neto, José

    2014-01-01

    Sexually selected signals are common in many animals, though little reported in social insects. We investigated the occurrence of male visual signals mediating the dominance relationships among males and female choice of sexual partner in the paper wasp Polistes simillimus. Males have three conspicuous, variable and sexually dimorphic traits: black pigmentation on the head, a pair of yellow abdominal spots and body size differences. By conducting behavioral assays, we found that none of the three visual traits are associated with male-male dominance relationship. However, males with higher proportion of black facial pigmentation and bigger yellow abdominal spots are more likely chosen as sexual partners. Also, after experimentally manipulating the proportion of black pigment on males' face, we found that females may evaluate male facial coloration during the choice of a sexual partner. Thus, the black pigmentation on P. simillimus male's head appears to play a role as a sexually selected visual signal. We suggest that sexual selection is a common force in Polistes and we highlight the importance of this group as a model for the study of visual communication in insects.

  2. A Phenomenological Study of What Black Male TRiO Student Support Services Program Members Attribute to Their Decision to Drop out of College

    Science.gov (United States)

    Jones, LaTonya S.

    2011-01-01

    Compared to other races, the college achievement gap is largest between Black men and women where females earn twice as many degrees as their male counterparts (National Center for Education Statistics, 2010, Status and trends in the education of racial and ethnic minorities). Many Black men attempt college and eventually drop out forfeiting their…

  3. Demonized No More: The Spiritual Journeys and Spaces of Black Gay Male College Students at Predominantly White Institutions

    Science.gov (United States)

    Means, Darris R.

    2014-01-01

    Spirituality plays a significant role in the lives of college students (Astin, Astin, & Lindholm, 2011; Bryant, Choi, & Yasuno, 2003; Chickering, 2006; Parks, 2000). However, Black gay males are uniquely positioned with regards to spirituality given how race, gender, and sexual orientation are generally perceived and experienced in the…

  4. Sexy faces in a male paper wasp.

    Directory of Open Access Journals (Sweden)

    André Rodrigues de Souza

    Full Text Available Sexually selected signals are common in many animals, though little reported in social insects. We investigated the occurrence of male visual signals mediating the dominance relationships among males and female choice of sexual partner in the paper wasp Polistes simillimus. Males have three conspicuous, variable and sexually dimorphic traits: black pigmentation on the head, a pair of yellow abdominal spots and body size differences. By conducting behavioral assays, we found that none of the three visual traits are associated with male-male dominance relationship. However, males with higher proportion of black facial pigmentation and bigger yellow abdominal spots are more likely chosen as sexual partners. Also, after experimentally manipulating the proportion of black pigment on males' face, we found that females may evaluate male facial coloration during the choice of a sexual partner. Thus, the black pigmentation on P. simillimus male's head appears to play a role as a sexually selected visual signal. We suggest that sexual selection is a common force in Polistes and we highlight the importance of this group as a model for the study of visual communication in insects.

  5. The (End)Angered Black Male Swimming against the Current

    Science.gov (United States)

    Guy, Talmadge C.

    2014-01-01

    This chapter discusses the sociohistorical and deeply embedded myths and stereotypes that have dominated narratives about Black men and how these shape the educational and professional experiences of Black men.

  6. Health, trust, or "just understood": explicit and implicit condom decision-making processes among black, white, and interracial same-sex male couples.

    Science.gov (United States)

    Campbell, Chadwick K; Gómez, Anu Manchikanti; Dworkin, Shari; Wilson, Patrick A; Grisham, Kirk K; McReynolds, Jaih; Vielehr, Peter; Hoff, Colleen

    2014-05-01

    Among gay and bisexual men, primary partners are a leading source of HIV infection. Trust, intimacy, and advancements in HIV treatment may impact same-sex male (SSM) couples' decisions to engage in unprotected anal intercourse (UAI). This qualitative study explored how Black, White and interracial couples discussed, and made decisions regarding condoms. Qualitative interviews were conducted with 48 SSM couples in the New York and San Francisco metropolitan areas. Stratified purposive sampling was used to include Black (n = 16), White (n = 17), and interracial (Black-White) (n = 15) couples. Twenty-six couples were concordant HIV-negative and 22 were HIV-discordant. Interviews were recorded, transcribed, coded, and analyzed using a grounded theory approach. Some couples described explicit processes, which involved active discussion, while others described implicit processes, where condom-use decisions occurred without any explicit discussion. These processes also differed by race and HIV status. Black couples tended to report condom-use as "just understood." White, HIV-discordant couples decided not to use condoms, with some identifying the HIV-positive partner's suppressed viral load and high CD4 count as deciding factors. After an unplanned episode of UAI, White, HIV-negative couples tended to discontinue condom use while Black HIV-negative couples decided to revert to using condoms. HIV prevention efforts focused on same-sex, male couples must consider the explicit/implicit nature of condom decision-making processes. Understanding differences in these processes and considering relationship dynamics, across race and HIV status, can promote the development of innovative couple-level, HIV prevention interventions.

  7. Behavioral and physiological responses to male handicap in chick-rearing black-legged kittiwakes

    Science.gov (United States)

    Leclaire, S.; Bourret, V.; Wagner, R.H.; Hatch, Shyla A.; Helfenstein, F.; Chastel, O.; Danchin, E.

    2011-01-01

    Parental investment entails a trade-off between the benefits of effort in current offspring and the costs to future reproduction. Long-lived species are predicted to be reluctant to increase parental effort to avoid affecting their survival. We tested this hypothesis in black-legged kittiwakes Rissa tridactyla by clipping flight feathers of experimental males at the beginning of the chick-rearing period. We analyzed the consequences of this handicap on feeding and attendance behavior, body condition, integument coloration, and circulating levels of corticosterone and prolactin in handicapped males and their mates in comparison to unmanipulated controls. Chicks in both groups were compared in terms of aggressive behavior, growth, and mortality. Handicapped males lost more mass, had less bright integuments, and attended the nest less often than controls. Nevertheless, they fed their chicks at the same rate and had similar corticosterone and prolactin levels. Compared with control females, females mated with handicapped males showed a lower provisioning rate and higher nest attendance in the first days after manipulation. Their lower feeding rate probably triggered the increased sibling aggression and mortality observed in experimental broods. Our findings suggest that experimental females adaptively adjusted their effort to their mate's perceived quality or that their provisioning was constrained by their higher nest attendance. Overall, our results suggest that kittiwake males can decrease their condition for the sake of their chicks, which seems to contradict the hypothesis that kittiwakes should be reluctant to increase parental effort to avoid affecting their survival. ?? 2011 The Author. Published by Oxford University Press on behalf of the International Society for Behavioral Ecology. All rights reserved.

  8. "I 'See' Trayvon Martin": What Teachers Can Learn from the Tragic Death of a Young Black Male

    Science.gov (United States)

    Love, Bettina L.

    2014-01-01

    The goal of this article is to examine the racially hostile environment of U.S. public schooling towards Black males. Drawing on the work of Foucault ("Discipline and punish. The birth of the prison," Penguin Books, London, 1977; "Michel Foucault: beyond structuralism and hermeneutics," The Harvester Press, Brighton, 1982)…

  9. The Effect of College Selection Factors on Persistence: An Examination of Black and Latino Males in the Community College

    Science.gov (United States)

    Wood, J. Luke; Harris, Frank, III

    2015-01-01

    The purpose of this study was to understand the relationship (if any) between college selection factors and persistence for Black and Latino males in the community college. Using data derived from the Educational Longitudinal Study, backwards stepwise logistic regression models were developed for both groups. Findings are contextualized in light…

  10. “They think you’re lazy,” and Other Messages Black Parents Send Their Black Sons: An Exploration of Critical Race Theory in the Examination of Educational Outcomes for Black Males

    Directory of Open Access Journals (Sweden)

    Rema Reynolds

    2010-05-01

    Full Text Available Parents play an integral role in the social, emotional, physical, and intellectual development of their children. We know that school success has been associated with parents’ involvement and engagement1 practices. Studies have shown that despite socioeconomic disparities, children whose parents are involved perform markedly better than those whose parents are not. Little research has looked exclusively at parent involvement and its effects on the educational outcomes of Black males. A qualitative study conducted with Black parents and their involvement and engagement practices as the focus proved that this relationship warrants scholarly attention using Critical Race Theory as a tool for examination. Parents in this study were involved in their children’s educational processes in ways not always validated or valued by schools. Instead of engaging in conventional forms of involvement such as volunteering in the classroom, parents spent time and resources supplementing their children’s education at home. Subtle acts of racism manifested through microaggressions were detected by parents when interfacing with school officials2 and these exchanges prompted candid conversations with their sons. According to the parents in this study, deliberate messages about racism and educator expectations were often critical supplements for their Black sons in order to ensure educational success.

  11. Consequences of Conservatism: Black Male Undergraduates and the Politics of Historically Black Colleges and Universities

    Science.gov (United States)

    Harper, Shaun R.; Gasman, Marybeth

    2008-01-01

    Previous research has highlighted numerous ways in which historically Black colleges and universities (HBCUs) offer more supportive educational environments for Black students than do predominantly White institutions (PWIs). Notwithstanding the consistency of these findings, persistence and graduation rates remain low for undergraduates,…

  12. Alcohol Use and Mental Health Conditions Among Black College Males: Do Those Attending Postsecondary Minority Institutions Fare Better Than Those at Primarily White Institutions?

    Science.gov (United States)

    Barry, Adam E; Jackson, Zachary; Watkins, Daphne C; Goodwill, Janelle R; Hunte, Haslyn E R

    2017-07-01

    While there is a sizeable body of research examining the association between alcohol use and mental health conditions among college students, there are sparse investigations specifically focusing on these associations among Black college students. This is concerning given Black college students face different stressors compared with their non-Black peers. Black males appear especially at risk, exhibiting increased susceptibility to mental health issues and drinking in greater quantities and more frequently than Black females. This investigation examined the association between alcohol consumption and mental health conditions among Black men attending institutions of higher education in the United States and sought to determine differences between Black men attending predominantly White institutions (PWIs) compared with those attending postsecondary minority institutions. Final sample included 416 Black men, 323 of which attended a PWI. Data were from the National College Health Assessment. Black men attending a PWI reported significantly greater levels of alcohol consumption and significantly more mental health conditions. Attendance at a minority-serving institution was associated with fewer mental health conditions among Black men. Future studies should seek to replicate these findings and conduct culturally sensitive and gender-specific research examining why Black men at PWIs report greater alcohol consumption and more mental health conditions than their peers attending postsecondary minority institutions.

  13. Demographic response of black bears at Cold Lake, Alberta, to the removal of adult males

    Science.gov (United States)

    Sargeant, Glen A.; Ruff, Robert L.

    2001-01-01

    Previous reports described an increase in population density following the removal of 23 adult male black bears (Ursus americanus) from a 218-km2 study area near Cold Lake, Alberta (the CLSA). This finding plays a central role in continuing debates over population regulation in bears, but has recently been criticized because density estimates were based on assumptions that were not met. Moreover, subsequent discussion has been predicated on conjecture that human exploitation had minimal influence on population dynamics. Our reanalysis supports previous descriptions of trends in bear density at Cold Lake. However, survival records revealed heavier exploitation than previously suspected. An underlying assumption of previous interpretationsCthat the Cold Lake bear population was naturally regulated near carrying capacityCno longer seems reasonable. Adult males deterred bears in other sex-age groups from using the CLSA; however, we found no evidence that birth or death rates were affected. The observed increase in local density should not be construed as a density-dependent response. Abrupt changes in local density might not have occurred if males had been removed from a larger area encompassing the CLSA.

  14. Hip Hop Culture's OGs: A Narrative Inquiry into the Intersection of Hip Hop Culture, Black Males and Their Schooling Experiences

    Science.gov (United States)

    Buchanan, Ian P.

    2013-01-01

    Using a critical race lens, this narrative study employs a focus group design to explore the intersections between black males, hip hop culture and schooling experiences. To provide a sociocultural grounding, this study first reviews the research literature around hip hop culture.s sociocultural development and its impact as a culture force that…

  15. Lianas as a food resource for brown howlers (Alouatta guariba and southern muriquis (Brachyteles arachnoides in a forest fragment

    Directory of Open Access Journals (Sweden)

    M. M. Martins

    2009-01-01

    Full Text Available Lianas as a food resource for brown howlers (Alouatta guariba and southern muriquis (Brachyteles arachnoides in a forest fragment.— Lianas, woody vines, are abundant and diverse in tropical forests, but their relative contribution as a source of food for herbivores has been neglected. I compared feeding rates on lianas and trees of two sympatric primates, A. guariba and B. arachnoides, in Southeastern Brazil. Availability of liana foods was gathered in parallel with primate behavioral data collection. Liana represented 33.9% and 27.3% of food sources for A. guariba and B. arachnoides, respectively. Foods coming from trees, rather than from lianas, were significantly more consumed by B. arachnoides. However, both species took advantage of the continuously renewable and ephemeral food resources provided by liana. Availability of liana flowers correlated positively with A. guariba feeding proportions. The nutritional supply provided by lianas is apparently beneficial, or at least unharmful, but experiments comparing primate choices in forests with different liana abundances will help to shed light on their possible negative effect on communities.

  16. Exploration of Factors Affecting Success of Undergraduate Engineering Majors at a Historically Black University

    Science.gov (United States)

    Igbinoba, Egheosa P.

    Blacks are underrepresented amongst persons who earn college degrees in the United States and Black males attend and complete college at a lower rate than Black females (Toldson, Fry Brown, & Sutton, 2009). According to Toldson et al. (2009), this quandary may be attributed to Black males' apathy toward education in general, waning support and ideological challenges toward Pell Grants and affirmative action, cultural incompetency on the part of the 90% White, ethnic makeup of the U.S. teaching force, and the relatively high numbers of Black males who are held back in school. In spite of the dismal statistics regarding Black male academic achievement and matriculation, there are those Black males who do participate in postsecondary education. While many studies have highlighted reasons that Black males do not achieve success in attending and persisting through college, few have adopted the anti-deficit research framework suggested by Harper (2010), identifying reasons Black males do persist in higher education. Although science, technology, engineering, and mathematics careers are identified as those most imperative to the economic competitiveness of the United States, few studies have concentrated solely on engineering majors and fewer, if any, solely on Black male engineering majors at an historically Black college and university. The aim of this study was to address an apparent gap in the literature and invoke theories for recruitment, retention, and success of Black males in engineering degree programs by employing an anti-deficit achievement framework for research of students of color in science, technology, engineering, and mathematics. Data garnered from the study included insight into participants' definitions of success, precollege experiences, factors contributing to the persistence during undergraduate study, and perceptions of attending a historically Black college and university versus a primarily White institution.

  17. Weaponization and Prisonization of Toronto’s Black Male Youth

    Directory of Open Access Journals (Sweden)

    Wesley Crichlow

    2014-12-01

    Full Text Available Informed by Galtung (1969, Anderson (2012 and Wacquant (2001, this paper argues that a lifetime of spiralling and everyday state structural violence and overtly racist criminal profiling principally targeted at young Black men living in the Toronto Community Housing Corporation prepares them for prison. Moreover, it contends that interpersonal violence, transmitted from generation to generation and producing a vicious cycle, is a manifestation of institutionalized and systemic inequity. In the context of a hypermasculine culture, young Black men are both victims and participants in a dialectic of interpersonal-structural violence. Routinely precipitated by powerful state actors and agencies of criminal justice, public policy and assorted ‘moral entrepreneurs’, young Black men have their masculinity weaponized and prisonized by the state’s low-intensity declaration of war against them, and, among others, the poor, LGBTQ, immigrants, and First Nations and other people of colour.

  18. Geographical distribution of the red howler monkey (Alouatta seniculus) and yellow fever in Colombia.

    Science.gov (United States)

    Piedrahita-Cortés, Juan; Soler-Tovar, Diego

    2016-02-11

    Colombia is a country with an important diversity of non-human primates, of which the red howler monkey (Alouatta seniculus) stands out because of its distribution and the role it plays in the occurrence of yellow fever.  To describe the geographic co-occurrence of Alouatta seniculus and the reported presence of yellow fever.  We conducted a descriptive study. The reported presence of yellow fever in Colombia was obtained from the reports and bulletins issued by the Instituto Nacional de Salud, and the study by Segura, et al. (2013). The occurrence of A. seniculus was determined based on the data from the Global Biodiversity Information Facility and the Colombian Biodiversity Information System. A map of the occurrence was developed using the DIVA-GIS program, and the ecological niche model under current conditions was created with the Maxent program.  The departments with the highest occurrence of A. seniculus were Antioquia, Meta and Casanare; 69.5% of the departments with reported history of yellow fever had co-occurrence with A. seniculus. The ecological niche model showed that Antioquia, Bolívar, La Guajira, Magdalena, Meta, Santander, Norte de Santander and Vichada had geographical portions with a probability rate nearing to 0.9 (90%).  In 69.5% of the departments with a history of yellow fever there was co-occurrence with A. seniculus, which is relevant because non-human primates play a well-known role as natural reservoirs of the virus, and they might contribute to the occurrence of the yellow fever, which makes them very useful as sentinels.

  19. Gender and the Residential Mobility and Neighborhood Attainment of Black-White Couples.

    Science.gov (United States)

    Gabriel, Ryan

    2018-04-01

    Including black-white couples in the study of residential stratification accentuates gendered power disparities within couples that favor men over women, which allows for the analysis of whether the race of male partners in black-white couples is associated with the racial and ethnic composition of their neighborhoods. I investigate this by combining longitudinal data between 1985 and 2015 from the Panel Study of Income Dynamics linked to neighborhood- and metropolitan-level data compiled from four censuses. Using these data, I assess the mobility of black male-white female and white male-black female couples out of and into neighborhoods defined respectively by their levels of whites, blacks, and ethnoracial diversity. My results show that the race of the male partner in black-white couples tends to align with the racial and ethnic composition of the neighborhoods where these couples reside. This finding highlights that the racial hierarchy within the United States affects the residential mobility and attainment of black-white couples, but its influence is conditioned by the race and gender composition of these couples.

  20. Male Adolescent Contraceptive Utilization.

    Science.gov (United States)

    Finkel, Madelon Lubin; Finkel, David J.

    1978-01-01

    The contraceptive utilization of a sample of sexually active, urban, high school males (Black, Hispanic, and White) was examined by anonymous questionnaire. Contraceptive use was haphazard, but White males tended to be more effective contraceptors than the other two groups. Reasons for nonuse were also studied. (Author/SJL)

  1. Estudo florístico de segmentos de Mata Atlântica em Parelheiros, São Paulo, SP, para soltura de bugio-ruivo Alouatta clamitans (Cabrera, 1940. Floristic survey of Atlantic Rain Forest in the District of Parelheiros, São Paulo, southeastern Brazil, for reintroduction of the Brown Howler Monkey, Alouatta clamitans (Cabrera, 1940

    Directory of Open Access Journals (Sweden)

    Ricardo José Francischetti GARCIA

    2014-06-01

    Full Text Available A fim de minimizar os efeitos da pressão da urbanização sobre bugios-ruivos, Alouatta clamitans (Cabrera, 1940, a Divisão de Fauna em parceria com o Herbário Municipal realiza, desde 1996, o Programa de Reintrodução de Bugios, com o objetivo de viabilizar o retorno à vida livre dos indivíduos aptos. Entre várias áreas prospectadas para possível soltura de bugios-ruivos, o Sítio Roda d’Água, distrito de Parelheiros, município de São Paulo, foi selecionado para realização do presente estudo. Todos os componentes da mata, em uma área de 89,9 hectares, foram amostrados para avaliação da disponibilidade de alimentos. Foram registradas 251 espécies vasculares, sendo 13 pteridófitas, uma gimnosperma e 237 angiospermas. O material testemunho está depositado no Herbário Municipal. Na área estudada foram registradas duas espécies ameaçadas e quatro quase ameaçadas. As espécies dos componentes arbóreo-arbustivo e epifítico, que constituem o hábitat preferencial dos bugios-ruivos, correspondem a 73,7% do total levantado. Dentro deste grupo de espécies, 17,8% já foram registradas como fontes alimentares para a espécie-alvo. Dentre as espécies já referidas na dieta de bugios-ruivos, registradas na área de estudo, todas apresentam distribuição geográfica ampla. Desta forma, a área estudada foi considerada apropriada para a soltura de bugios-ruivos, quanto à disponibilidade de recursos para alimentação. In order to minimize the urbanization pressure effects over Brown Howler Monkeys, Alouatta clamitans (Cabrera, 1940, the Fauna Division in partnership with the Municipal Herbarium carries out a Brown Howler Monkey Reintroduction Program since 1996, with the aim of enabling the return of fit individuals to the wild. Among several areas prospected for possible reintroduction of the Brown Howler Monkey, Roda d’Água Ranch, District of Parelheiros, City of São Paulo, was selected to carry out this study. All

  2. Whites excrete a water load more rapidly than blacks.

    Science.gov (United States)

    Weder, Alan B; Gleiberman, Lillian; Sachdeva, Amit

    2009-04-01

    A recent report demonstrated a racial difference in response to furosemide compatible with increased ion reabsorption in the thick ascending limb of the loop of Henle in blacks. Urinary dilution is another function of the loop-diuretic-sensitive Na,K,2Cl cotransporter in the thick ascending limb, and racial differences in urinary diluting capacity have not been reported previously. We assessed diluting segment (cortical thick ascending limb and distal convoluted tubule) function in black and white normotensives in 2 studies using a water-loading approach. In both studies, we found that whites excreted a water load more rapidly than blacks. In the first study, the final free water clearance rates (mean+/-SD) were 7.3+/-4.7 mL/min in whites (n=17, 7 females and 10 males) and 3.8+/-3.6 mL/min in blacks (n=14, 9 females and 5 males; Pwater clearance rates were 8.3+/-2.6 mL/min in whites (n=17, 8 females and 9 males) and 6.4+/-1.8 mL/min in blacks (n=11, 8 females and 3 males; Pwater excretion. We conclude that our observations are most consistent with a lower capacity of ion reabsorption in the renal diluting segment in blacks. Slower excretion of an acute water load may have been an advantage during natural selection of humans living in arid, hot climates.

  3. Communication Apprehension among Black Students on Predominantly White Campuses.

    Science.gov (United States)

    Byrd, Marquita L.; Sims, Anntarie L.

    1987-01-01

    A study of 114 Black undergraduates in two predominantly White midwestern universities demonstrates that communication apprehension (CA) among Blacks appears to be an audience-based phenomenon. Black females scored lower than Black males on the Personal Report of Communication Apprehension-24 (PRCA-24). The higher the CA score, the higher the…

  4. Census Undercount and the Undercount of the Black Population.

    Science.gov (United States)

    Nguyen, Phung

    1996-01-01

    Argues that blacks have been disproportionately undercounted in the census and this undercount has resulted in such biased statistics as proportions of black female-headed households, victimization rates of black males, or crude death rates of blacks. Further, these statistics are biased upward and downward, and together they generate distorted…

  5. Black Males and Crime and Delinquency: Violence in Search of Purpose.

    Science.gov (United States)

    Pearson, Dale F.

    1994-01-01

    Economic restructuring has exacerbated problems of black men such as poverty, unemployment, lowered life expectancy, and low expectations. Power diverted from productive channels is expressed in gang violence, homicide, and suicide. Recommendations include a national agency to eliminate poverty, involve the black community, and increase funding…

  6. The Racial Hauntings of One Black Male Professor and the Disturbance of the Self(ves): Self-Actualization and Racial Storytelling as Pedagogical Practices

    Science.gov (United States)

    Johnson, Lamar L.

    2017-01-01

    Through a series of racialized stories, I illustrate the familial knowledge, racial hauntings, and educational experiences that forge(d) the beginning and the continuing of my racial identity as a Black male. To examine these stories, I employ racial storytelling as a theoretical, methodological, curricular, and pedagogical tool to assist me in a…

  7. Primary vesicoureteral reflux in Blacks with posterior urethral valves: Does it occur?

    International Nuclear Information System (INIS)

    Nancarrow, P.A.; Lebowitz, R.L.

    1988-01-01

    Primary vesicoureteral reflux (VUR) is thought to be largely independent of obstruction. Therefore, in patients with urethral obstruction due to posterior urethral valves (PUV) the occurrence of VUR is coincidental. In addition, primary VUR is reported to be uncommon in black children. If these two premises are correct, then primary VUR should be rare in black males with PUV. To test this hypothesis, we reviewed the medical records and radiographs of 43 males with PUV. Twenty-one of the 37 non-black males with PUV had VUR, of which 67% was primary and 33% was secondary. Three of the six Blacks with PUV had VUR of which none was primary and all was secondary. Thus, Blacks with PUV lend credence to the theory that primary VUR is not caused by obstruction and support the observation that primary VUR is rare in black children, even those with PUV. (orig.)

  8. Perceived Discrimination among Black Youth: An 18-Year Longitudinal Study

    Directory of Open Access Journals (Sweden)

    Shervin Assari

    2018-04-01

    Full Text Available Background: Recent research has suggested vulnerability to perceived racial discrimination (PRD as a mechanism behind high levels of depression seen in high socioeconomic status (SES Black males. To better understand the effects of gender and SES on shaping experiences of PRD among Black youth in the United States, we used data from the Family and Community Health Study (FACHS to explore the trajectory of PRD in Black youth by gender, SES, and place. Methods: Data came from FACHS, 1997–2017, which followed 889 children aged 10–12 years old at Wave 1 (n = 478; 53.8% females and n = 411; 46.2% males for up to 18 years. Data were collected in seven waves. The main predictors of interest were gender, SES (parent education and annual family income, age, and place of residence. Main outcomes of interest were baseline and slope of PRD. Latent growth curve modeling (LGCM was used for data analysis. Results: Gender, SES, place, and age were correlated with baseline and change in PRD over time. Male, high family income, and younger Black youth reported lower PRD at baseline but a larger increase in PRD over time. Youth who lived in Iowa (in a predominantly White area reported higher PRD at baseline and also an increase in PRD over time. High parental education was not associated with baseline or change in PRD. Conclusion: In the United States, Black youth who are male, high income, and live in predominantly White areas experience an increase in PRD over time. Future research is needed on the interactions between gender, SES, and place on exposure and vulnerability of Black youth to PRD. Such research may explain the increased risk of depression in high SES Black males.

  9. The Nigrescence of the "Okay" Brother: a Phenomenological Study on the Impact of an Education in a Traditionally White Learning Institution on the Racial Identity Development of Black Males in Professional Careers

    Science.gov (United States)

    Edwards, Hayley E.

    2012-01-01

    There are many stereotypes of the Black male that have been portrayed in the media through news stories, film, and television. They are often portrayed as shiftless, lazy, violent, or subservient, or praised for their athletic prowess, their music, or their value as entertainers. Occasionally, Black men are portrayed as the lone person of color…

  10. Hispanic and Black American Adolescents' Beliefs Relating to Sexuality and Contraception.

    Science.gov (United States)

    Scott, Clarissa S.; And Others

    1988-01-01

    Explored the level of scientific knowledge regarding sexuality and contraception of Black and Hispanic inner-city adolescents. Results indicated that Hispanic males were the most knowledgeable, Hispanic females the least, and Black males and females were intermediate. A cultural basis for this difference is considered, and the need to design…

  11. Educational Lynching: Critical Race Theory and the Suspension of Black Boys

    Science.gov (United States)

    Payne, Macheo

    2010-01-01

    Looking at the disproportionate suspension of African American, Black male students through the lens of critical race theory, this presents arguments from a CRT how the disproportionate suspension of Black male students is rooted in white supremacy and racist policy in the United States. Local recommendations are offered for Oakland Unified School…

  12. Vignettes of scholars: A case study of black male students at a STEM early college high school

    Science.gov (United States)

    Adams, Tempestt Richardson

    Ensuring students graduate high school ready to enter college or the workforce has become a prime focus within secondary education. High school graduates are often ill-prepared for college-level work and often have to register for remedial courses before they can take standard college level courses (Southern Regional Education Board, 2010). Serving as both a solution to this concern and an alternative to traditional high schools, early college high schools were created to focus on increasing the number of students graduating from high school and enrolling in college. Early college high schools seek to serve students who have traditionally underperformed in school and those who are underrepresented in higher education including students of color, first-generation college students, students from low socioeconomic backgrounds, and English language learners (Barnett, Bucceri, Hindo, Kim, 2013; "Overview & FAQS," 2013). In efforts to learn more about how early colleges are meeting the needs of students, this dissertation examines the experiences, identity construction, and perceptions of Black male students at a science, technology, engineering, and mathematics (STEM) based early college high school. Using a qualitative case study design, participants were eight Black male upperclassmen enrolled in a STEM early college high school, located on the campus of a four-year university. Data was collected through focus groups and individual interviews and data was analyzed thematically. Findings suggest students in this study have largely positive experiences at their early college high school. Despite some challenges, the early college high school environment helps facilitate scholar identities, and the STEM focus of the school helps students learn more about their strengths and weaknesses. The implications of the research, recommendations for educational stakeholders, and recommendations for future research are discussed.

  13. Seminal fluid enhances competitiveness of territorial males' sperm in a fish with alternative male reproductive tactics.

    Science.gov (United States)

    Poli, Federica; Locatello, Lisa; Rasotto, Maria B

    2018-05-29

    The most common adaptation to sperm competition in males is represented by an increase in the sperm number and/or quality released at mating, to raise their probability of egg fertilization. However, rapidly mounting evidence highlights that seminal fluid may directly influence the competitive fertilization success of a male by affecting either own and/or rival sperm performances. In the black goby, Gobius niger , an external fertilizer with guard-sneaker mating tactics and high sperm competition level, sneaker males' ejaculates contain less seminal fluid and more sperm, that are also of better quality, than those of territorial males. However, territorial males, gain a higher paternity success inside natural nests. Here, we ask whether the seminal fluid can contribute to territorial males' reproductive success by enhancing their sperm performances and/or by decreasing those of sneaker males. Using sperm and seminal fluid manipulation and in vitro fertilization tests, we found that own seminal fluid influences the velocity and fertilization ability of sperm only in territorial males, making them as faster as those of sneakers and with similar fertilization rate. Moreover, both sneaker and territorial males' sperm remain unaffected by the seminal fluid of rival males. Thus, black goby males respond to the different level of sperm competition faced by differently allocating in sperm and non-sperm components of the ejaculate, with sneakers primarily investing in sperm of intrinsic high quality and territorial males relying on the effect of seminal fluid to increase the lower intrinsic quality of their sperm. © 2018. Published by The Company of Biologists Ltd.

  14. Pride and Purpose as Antidotes to Black Homicidal Violence

    Science.gov (United States)

    Thomas, Charles W.

    1987-01-01

    The incidence of black male homicide is a major public menace. The lowest incidence of black male homicide was when the black power movement was visible and flourishing. Psychohistorical data support the contention that racial pride is an effective means for regulating intragroup tensions. In the absence of an Afrocentric orientation that promotes community power and self-determination, the need for self-reliance is eroded by value illnesses. The value orientation of the black movement supplied the pride used to obtain academic success, to reduce juvenile delinquency, and to help Afro-Americans to structure their lives for personal satisfactions. Blackness has always been about personal power and social control, but society does not allow much access to either for Afro-Americans. As a consequence, stress from racism is severe, asymptomatic, and multi-faceted. The best antidote to black homicidal violence comes from a pro-social effort based upon a self-image that gives a feeling of positive accomplishment and appreciation. Afrocentric pride promotes or enhances pro-social behavior. PMID:3560242

  15. Overexpression of rice black-streaked dwarf virus p7-1 in Arabidopsis results in male sterility due to non-dehiscent anthers.

    Directory of Open Access Journals (Sweden)

    Feng Sun

    Full Text Available Rice black-streaked dwarf virus (RBSDV, a member of the genus Fijivirus in the family Reoviridae, is propagatively transmitted by the small brown planthopper (Laodelphax striatellus Fallén. RBSDV causes rice black-streaked dwarf and maize rough dwarf diseases, which lead to severe yield losses in crops in China. Although several RBSDV proteins have been studied in detail, the functions of the nonstructural protein P7-1 are still largely unknown. To investigate the role of the P7-1 protein in virus pathogenicity, transgenic Arabidopsis thaliana plants were generated in which the P7-1 gene was expressed under the control of the 35S promoter. The RBSDV P7-1-transgenic Arabidopsis plants (named P7-1-OE were male sterility. Flowers and pollen from P7-1-transgenic plants were of normal size and shape, and anthers developed to the normal size but failed to dehisce. The non-dehiscent anthers observed in P7-1-OE were attributed to decreased lignin content in the anthers. Furthermore, the reactive oxygen species levels were quite low in the transgenic plants compared with the wild type. These results indicate that ectopic expression of the RBSDV P7-1 protein in A. thaliana causes male sterility, possibly through the disruption of the lignin biosynthesis and H2O2-dependent polymerization pathways.

  16. Overexpression of rice black-streaked dwarf virus p7-1 in Arabidopsis results in male sterility due to non-dehiscent anthers.

    Science.gov (United States)

    Sun, Feng; Yuan, Xia; Xu, Qiufang; Zhou, Tong; Fan, Yongjian; Zhou, Yijun

    2013-01-01

    Rice black-streaked dwarf virus (RBSDV), a member of the genus Fijivirus in the family Reoviridae, is propagatively transmitted by the small brown planthopper (Laodelphax striatellus Fallén). RBSDV causes rice black-streaked dwarf and maize rough dwarf diseases, which lead to severe yield losses in crops in China. Although several RBSDV proteins have been studied in detail, the functions of the nonstructural protein P7-1 are still largely unknown. To investigate the role of the P7-1 protein in virus pathogenicity, transgenic Arabidopsis thaliana plants were generated in which the P7-1 gene was expressed under the control of the 35S promoter. The RBSDV P7-1-transgenic Arabidopsis plants (named P7-1-OE) were male sterility. Flowers and pollen from P7-1-transgenic plants were of normal size and shape, and anthers developed to the normal size but failed to dehisce. The non-dehiscent anthers observed in P7-1-OE were attributed to decreased lignin content in the anthers. Furthermore, the reactive oxygen species levels were quite low in the transgenic plants compared with the wild type. These results indicate that ectopic expression of the RBSDV P7-1 protein in A. thaliana causes male sterility, possibly through the disruption of the lignin biosynthesis and H2O2-dependent polymerization pathways.

  17. "I Have Goals to Prove All Those People Wrong and Not Fit into Any One of Those Boxes": Paths of Resistance to Stereotypes among Black Adolescent Males

    Science.gov (United States)

    Rogers, Leoandra Onnie; Way, Niobe

    2016-01-01

    Adolescents form their identities by both accommodating (endorsing) and resisting (challenging) cultural stereotypes. Most research on Black males focuses on how they accommodate to negative stereotypes (e.g., delinquency, aggression), but a growing literature emphasizes how youth resist stereotypes. Semi-structured interviews were analyzed to…

  18. Prevalence and acceptability of male circumcision in South Africa ...

    African Journals Online (AJOL)

    ... groups and having heard of the HIV protective effect of male circumcision were significant predictors for male circumcision acceptability, and among women with a non-circumcised sexual partner, Black African and Coloured population groups and higher education were predictors for male circumcision acceptability.

  19. Assessment of the bone quality of black male athletes using calcaneal ultrasound: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Sendeht Ayuba J

    2008-05-01

    Full Text Available Abstract Background Lifestyle, genetics and environmental factors are established determinants of bone density. We aimed to describe the bone characteristics of competitive top-ranked Nigerian male athletes using calcaneal ultrasound and to assess whether intensive training promotes higher bone density in an environment with reportedly low calcium intake; to compare the bone characteristics of footballers with runners and other sportsmen; and to assess the correlation of stiffness index (SI with activity level, since energy expenditure correlates with length of training and by extension, magnitude of skeletal loading. Methods We recruited 102 male athletes: these included football (n = 68, running (n = 15, handball (n = 7, taekwando (n = 6, cycling (n = 2, judo (1, badminton (1 and high jump (1. Anthropometric data were first recorded on a structured form and energy expenditure was indirectly estimated with a validated questionnaire. Bone density was assessed using the Lunar Achilles+ calcaneal ultrasonometer. Results The mean age of athletes was 25 ± 6 years. The means of BMI and energy expenditure were 21.9 ± 2.0 kg/m2 and 35.0 ± 13.7 kcal/kg/day, respectively. Footballers were younger (p Conclusion Repetitive skeletal loading at the heel has the potential to improve bone density in black male athletes. The magnitude of increase may be higher in medium impact sports such as soccer and running compared with low or non-impact sports such as judo or taekwando, and is independent of age and BMI. However, future longitudinal data will be required to support our observations.

  20. Black and White Viewers' Perception and Recall of Occupational Characters on Television.

    Science.gov (United States)

    Appiah, Osei

    2002-01-01

    Examines the differences in how Black and White viewers process messages based on the race of television characters representing five occupations. Notes that findings from male college students suggest that Black viewers have better recall of Black occupational characters than White characters on television. Reveals evidence that both Black and…

  1. An Exploration of the Impact of Critical Math Literacies and Alternative Schooling Spaces on the Identity Development of High School-Aged Black Males in South Los Angeles

    Science.gov (United States)

    Terry, Clarence La Mont

    2009-01-01

    Urban schools, for many African American students, have effectively become a space for the perpetuation of modern slavery. Large numbers of students, particularly Black males, are being funneled without choice into low-wage labor sectors, military service, underground economies and, eventually, prisons or worse. Key work by math education…

  2. Differentiation in boron distribution in adult male and female rats' normal brain: A BNCT approach

    Energy Technology Data Exchange (ETDEWEB)

    Goodarzi, Samereh, E-mail: samere.g@gmail.com [Department of Nuclear Engineering, Science and Research Branch, Islamic Azad University, PO Box 19395-1943, Tehran (Iran, Islamic Republic of); Pazirandeh, Ali, E-mail: paziran@yahoo.com [Department of Nuclear Engineering, Science and Research Branch, Islamic Azad University, PO Box 19395-1943, Tehran (Iran, Islamic Republic of); Jameie, Seyed Behnamedin, E-mail: behnamjameie@tums.ac.ir [Basic Science Department, Faculty of Allied Medicine, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Department of Anatomy, Faculty of Medicine, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Baghban Khojasteh, Nasrin, E-mail: khojasteh_n@yahoo.com [Department of Nuclear Engineering, Science and Research Branch, Islamic Azad University, PO Box 19395-1943, Tehran (Iran, Islamic Republic of)

    2012-06-15

    Boron distribution in adult male and female rats' normal brain after boron carrier injection (0.005 g Boric Acid+0.005 g Borax+10 ml distilled water, pH: 7.4) was studied in this research. Coronal sections of control and trial animal tissue samples were irradiated with thermal neutrons. Using alpha autoradiography, significant differences in boron concentration were seen in forebrain, midbrain and hindbrain sections of male and female animal groups with the highest value, four hours after boron compound injection. - Highlights: Black-Right-Pointing-Pointer Boron distribution in male and female rats' normal brain was studied in this research. Black-Right-Pointing-Pointer Coronal sections of animal tissue samples were irradiated with thermal neutrons. Black-Right-Pointing-Pointer Alpha and Lithium tracks were counted using alpha autoradiography. Black-Right-Pointing-Pointer Different boron concentration was seen in brain sections of male and female rats. Black-Right-Pointing-Pointer The highest boron concentration was seen in 4 h after boron compound injection.

  3. Black-white differences in the economic value of improving health.

    Science.gov (United States)

    Murphy, Kevin M; Topel, Robert H

    2005-01-01

    This article examines how differences in longevity over time and across groups add to the typical measures of economic progress and intergroup differentials. We focus on gains for and differences between groups defined both by race (black and white) and by gender, relying on willingness to pay as our measure of the economic value of gains in longevity. Measured at birth, the gains for white males between 1968 and 1998 were about 245,000 dollars per person, while the gains for black males were far larger, about 390,000 dollars per person. The gains for women were somewhat smaller, with white females gaining about 150,000 dollars per person and black females gaining about 305,000 dollars per person. Our estimates suggest that differences in income explain about 1/3 to 1/2 of the current black-white gap in longevity.

  4. Intersectionality, critical race theory, and American sporting oppression: examining black and gay male athletes.

    Science.gov (United States)

    Anderson, Eric; McCormack, Mark

    2010-01-01

    This article examines the influence of the racial categories of White and Black and the sexual categories of gay and straight on sporting American men. The effect of the intersection of these cultural categories is discussed by investigating the exclusion of athletes who are both Black and gay, as well as highlighting the culturally perceived differences of (straight) Black and (White) gay men. However, the analysis accounts for more than just difference, examining the commonalities of oppression between these discrete identity groups. We use the research on Black athletes to call for further empirical study on gay athletes. It is argued that critical race theory and intersectionality offer complex and nuanced understandings of these oppressions, which, when theorizing is left solely to the realm of poststructuralism, can otherwise be missed.

  5. Romanticism and Eroticism among Black and White College Students.

    Science.gov (United States)

    Houston, Lawrence N.

    1981-01-01

    A questionnaire was administered to 1,142 Black and White university students of both sexes in an effort to determine the relationship between eroticism, romanticism and sexual identity. Results indicated that males were more erotic, females more romantic, and that the discrepancy was greater for Blacks than for Whites. (Author/CM)

  6. More Young Black Men Choosing Not to Go to College.

    Science.gov (United States)

    Collison, Michele N-K

    1987-01-01

    More and more young Black males are choosing to enlist in the military, attend vocational and technical schools, or take jobs instead of going to college. Many yield to peer pressure and stop studying; further, role models do not exist for young Black men. (MLW)

  7. Being White in Black Spaces: Teaching and Learning at a Predominately Black Institution

    Science.gov (United States)

    Harrington, Timothy E.; Thomas, Michael

    2018-01-01

    This paper serves as a beginning conversation of how two White males perspectives' were shaped and how those perspectives evolved while attending and teaching at a Predominately Black Institution (PBI). Their initial understandings of Whiteness are introduced. This is an ethnographic study that utilized personal narratives from a college professor…

  8. Social Determinants of Perceived Discrimination among Black Youth: Intersection of Ethnicity and Gender.

    Science.gov (United States)

    Assari, Shervin; Caldwell, Cleopatra Howard

    2018-02-15

    Most of the existing sociological and epidemiological literature has focused on the protective effects of high socioeconomic status (SES) on population health through reducing exposure to risk factors and increasing human and material resources that can mitigate adversities. Recent studies, however, have documented poor mental health of high SES Blacks, particularly African American males and Caribbean Black females. The literature also shows a link between perceived discrimination and poor mental health. To better understand the extra costs of upward social mobility for minority populations, this study explored ethnic by gender variations in the associations between SES indicators and perceived discrimination in an ethnically diverse national sample of Black youth. This study included 810 African American and 360 Caribbean Black youth who were sampled in the National Survey of American Life-Adolescent supplement (NSAL-A). Three SES indicators (financial hardship, family income, and income to needs ratio) were the independent variables. The dependent variable was perceived (daily) discrimination. Age was the covariate. Ethnicity and gender were the focal moderators. Linear regressions were used for data analysis in the pooled sample and also based on the intersection of ethnicity and gender. Considerable gender by ethnicity variations were found in the patterns of the associations between SES indicators and perceived discrimination. Financial hardship was a risk factor for perceived discrimination in African American males only. High family income and income to needs ratio were associated with high (but not low) perceived discrimination in African American males and Caribbean Black females. SES indicators were not associated with perceived discrimination for African American females or Caribbean Black males. When it comes to Black youth, high SES is not always protective. Whether SES reduces or increases perceived discrimination among Black youth depends on the

  9. Social Determinants of Perceived Discrimination among Black Youth: Intersection of Ethnicity and Gender

    Directory of Open Access Journals (Sweden)

    Shervin Assari

    2018-02-01

    Full Text Available Most of the existing sociological and epidemiological literature has focused on the protective effects of high socioeconomic status (SES on population health through reducing exposure to risk factors and increasing human and material resources that can mitigate adversities. Recent studies, however, have documented poor mental health of high SES Blacks, particularly African American males and Caribbean Black females. The literature also shows a link between perceived discrimination and poor mental health. To better understand the extra costs of upward social mobility for minority populations, this study explored ethnic by gender variations in the associations between SES indicators and perceived discrimination in an ethnically diverse national sample of Black youth. This study included 810 African American and 360 Caribbean Black youth who were sampled in the National Survey of American Life—Adolescent supplement (NSAL-A. Three SES indicators (financial hardship, family income, and income to needs ratio were the independent variables. The dependent variable was perceived (daily discrimination. Age was the covariate. Ethnicity and gender were the focal moderators. Linear regressions were used for data analysis in the pooled sample and also based on the intersection of ethnicity and gender. Considerable gender by ethnicity variations were found in the patterns of the associations between SES indicators and perceived discrimination. Financial hardship was a risk factor for perceived discrimination in African American males only. High family income and income to needs ratio were associated with high (but not low perceived discrimination in African American males and Caribbean Black females. SES indicators were not associated with perceived discrimination for African American females or Caribbean Black males. When it comes to Black youth, high SES is not always protective. Whether SES reduces or increases perceived discrimination among Black youth

  10. VIOLENT BLACK MAN AND THE MYTH OF BLACK MACHO IN EUGENE O’NEILL’S "THE DREAMY KID"

    Directory of Open Access Journals (Sweden)

    Agnieszka Łobodziec

    2014-10-01

    Full Text Available The aim of this article is the investigation of the extent to which Eugene O’Neill, in his drama "The Dreamy Kid", (reconstructs, or employs, the black macho myth, which negatively images black men as marginalized and violent. This undertaking questions O’Neill’s self-proclaimed progressive racial attitudes and stated focus on the universal nature of human existence, which he professed to express through drama. Moreover, the article challenges the mainstream view of "The Dreamy Kid" as progressive. Although the play focalizes the experience of a marginalized black man, which could be interpreted as the playwright’s concern with the unjust racial and class stratification of American society, O’Neill’s production, unfortunately, contains a number of pervasive stereotypes relative to black people’s alleged moral degeneracy, primitiveness, and violent behavior, which threatens the white dominated constructed order. In terms of gendered racial politics, in the article attention is given to O’Neill’s presentation of black male negotiations with the white patriarchal power structure, embodied by the police forces, and with black matriarchy, represented by O’Neill’s stereotypical character portrayal of a dominant elderly black woman. Lastly, an overall analysis is performed in light of the call for an autonomous black art, which emerged among black artists in opposition to the demeaning, unrealistic, stereotypical portrayals of black victims of oppression by white American writers.

  11. Affirmative action and the Black women in South Africa.

    Science.gov (United States)

    Serote, P

    1994-02-01

    An overview was given of how affirmative action for Blacks and women in South Africa in fact marginalizes Black women. The definition of the problem influences the solution; affirmative action obscures the complex nature of discrimination experienced by Black women by class, role, and culture and focuses only on gender and race. Secondly, the power of White women and Black men supercede the power of Black women. Apartheid benefitted White women over Black men. Affirmative action, as shifting power between groups, would solidify White women's power. The debates have taken place within university and academic contexts, a place where Black women have been excluded and the dominant groups are White men, followed by White women, and then Black men. The debate in the private sector also is devoid of Black women's voices; multinationals began to hire and train Black male managers, and there was criticism that standards were falling. Recruitment of Black women is unknown, but only 1.1% of managers are Black. Visibility within the academic and private sector debates has excluded Black women. In the articulation of ideas, most literature has been written by White men. The intersection of power and privilege belongs to males and White women as part of the larger dominant ideology. Black women's marginalization means their issues will not be addressed. The people who stand to benefit the most from affirmative action are those who are in need of improved living conditions, literacy, and employment, or those excluded from jobs and position in spite of being qualified. Black women without a societal power base have no bargaining power. To insure that Black women benefit, there is need to treat Black women as a distinctive group with priority. There is also a need to examine the myths that have been spun around Black women, their needs, abilities, and controlling images. There is a need to integrate Black womens ideas into the mainstream and recognize that maybe Black women need

  12. Empty Promise: Black American Veterans and the New GI Bill

    Science.gov (United States)

    Ottley, Alford H.

    2014-01-01

    The 2008 GI Bill offers college funds for veterans. Yet Black male vets are not taking advantage of these benefits. This chapter examines personal and societal problems that hinder access to higher education for Black vets, and suggests some ways adult educators can advocate for these young men.

  13. Job Orientation of Black and White College Graduates in Business.

    Science.gov (United States)

    Brenner, O. C.; Tomkiewicz, Joseph

    1982-01-01

    Examined differences in job orientation between Black and White male and female business college graduates. Significant race differences were found. Factor analysis indicates that Blacks value long-range career objectives and structure considerably more than do Whites, while their preference for intrinsic and extrinsic factors was less pronounced.…

  14. Length of Coronary Sinus in a Black Kenyan Population: Correlation ...

    African Journals Online (AJOL)

    The aim of the current study was to determine the length of coronary sinus among black Kenyans. Coronary sinuses of seventy-four hearts (43 males and 31 females) of adult age range (20-70years) black Kenyans obtained during autopsy were studied at the Department of Human Anatomy, University of Nairobi, Kenya.

  15. Social network analysis of mating patterns in American black bears (Ursus americanus).

    Science.gov (United States)

    Moore, Jennifer A; Xu, Ran; Frank, Kenneth; Draheim, Hope; Scribner, Kim T

    2015-08-01

    Nonrandom mating can structure populations and has important implications for population-level processes. Investigating how and why mating deviates from random is important for understanding evolutionary processes as well as informing conservation and management. Prior to the implementation of parentage analyses, understanding mating patterns in solitary, elusive species like bears was virtually impossible. Here, we capitalize on a long-term genetic data set collected from black bears (Ursus americanus) (N = 2422) in the Northern Lower Peninsula (NLP) of Michigan, USA. We identified mated pairs using parentage analysis and applied logistic regression (selection) models that controlled for features of the social network, to quantify the effects of individual characteristics, and spatial and population demographic factors on mating dynamics. Logistic regression models revealed that black bear mating was associated with spatial proximity of mates, male age, the time a pair had coexisted, local population density and relatedness. Mated pairs were more likely to contain older males. On average, bears tended to mate with nearby individuals to whom they were related, which does not support the existence of kin recognition in black bears. Pairwise relatedness was especially high for mated pairs containing young males. Restricted dispersal and high male turnover from intensive harvest mortality of NLP black bears are probably the underlying factors associated with younger male bears mating more often with female relatives. Our findings illustrate how harvest has the potential to disrupt the social structure of game species, which warrants further attention for conservation and management. © 2015 John Wiley & Sons Ltd.

  16. Use of Black English and Racial Discrimination in Urban Housing Markets.

    Science.gov (United States)

    Massey, Douglas S.; Lundy, Garvey

    2001-01-01

    Compared male and female speakers of white middle class English, black accented English, and black English vernacular in their telephone contacts with rental agents who were advertising apartments for rent in Philadelphia. Results found clear, dramatic evidence of telephone-based racial discrimination. Callers perceived as lower class black…

  17. Childhood risk factors associated with adolescent gun carrying among Black and White males: An examination of self-protection, social influence, and antisocial propensity explanations.

    Science.gov (United States)

    Beardslee, Jordan; Docherty, Meagan; Mulvey, Edward; Schubert, Carol; Pardini, Dustin

    2018-04-01

    Adolescent gun violence is a serious public health issue that disproportionately affects young Black males. Although it has been postulated that differential exposure to childhood risk factors might account for racial differences in adolescent gun carrying, no longitudinal studies have directly examined this issue. We examined whether childhood risk factors indexing neighborhood crime, peer delinquency, and conduct problems predicted the initiation of adolescent gun carrying among a community sample of Black and White boys. Analyses then examined whether racial differences in risk factors accounted for racial differences in gun carrying. Data came from a sample of 485 Black and White boys who were repeatedly assessed from 2nd grade until age 18. Multi-informant data collected across the first 3 years of the study were used to assess neighborhood crime, peer delinquency, and conduct problems. Illegal gun carrying was assessed annually from 5th grade through age 18. Growth curve analyses indicated that children with higher initial levels of conduct problems and delinquent peer involvement, as well as those who increased in conduct problems across childhood, were more likely to carry a gun prior to age 18. Black boys were also more likely to carry guns than Whites. Racial differences were greatly reduced, but not eliminated, after controlling for initial levels of conduct problems and delinquent peer involvement. Findings suggest that early prevention programs designed to reduce adolescent gun violence (including racial disparities in gun violence) should target boys with severe conduct problems and those who affiliate with delinquent peers during elementary school. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  18. Psychological Predictors of Sexual Intimate Partner Violence against Black and Hispanic Women

    Directory of Open Access Journals (Sweden)

    Brianna Preiser

    2017-12-01

    Full Text Available Background: Although various types of intimate partner violence (IPV tend to co-occur, risk factors of each type of IPV may differ. At the same time, most of the existing literature on risk factors of IPV among minorities has used a cross-sectional design and has focused on physical rather than sexual IPV. We conducted the current study to compare Black and Hispanic women for psychological predators of change in sexual IPV over time. Methods: Using data from the Fragile Families and Child Wellbeing Study (FFCWS, this study followed 561 Black and 475 Hispanic women with their male partners for four years. Independent variables included male partners’ depression, anxiety, problem alcohol use, and male-to-female physical and psychological IPV perpetration. The dependent variable was sexual IPV reported by female partners, measured at baseline, two years, and four years later. Covariates included age, income, marital status and educational level. We used a multi-group latent growth curve model (LGCM to explain intercept, linear, and quadratic slopes, which represent the baseline, and linear and curvilinear trajectories of male-to-female sexual IPV, where groups were defined based on ethnicity. Results: Psychological IPV was associated with sexual IPV at baseline among both ethnic groups. The male partner’s depression was a risk factor for an increase in sexual IPV over time among Black but not Hispanic women. Anxiety, problem alcohol use and physical IPV did not have an effect on the baseline or change in sexual IPV over time. Psychological IPV was not associated with an increase in sexual IPV over time in either ethnic groups. Conclusions: There is a need for screening of sexual IPV in the presence of psychological IPV among minority women. There is also a need for screening and treatment of male partners’ depression as a strategy to reduce sexual IPV among Black women.

  19. Psychological Predictors of Sexual Intimate Partner Violence against Black and Hispanic Women.

    Science.gov (United States)

    Preiser, Brianna; Assari, Shervin

    2017-12-27

    Background: Although various types of intimate partner violence (IPV) tend to co-occur, risk factors of each type of IPV may differ. At the same time, most of the existing literature on risk factors of IPV among minorities has used a cross-sectional design and has focused on physical rather than sexual IPV. We conducted the current study to compare Black and Hispanic women for psychological predators of change in sexual IPV over time. Methods: Using data from the Fragile Families and Child Wellbeing Study (FFCWS), this study followed 561 Black and 475 Hispanic women with their male partners for four years. Independent variables included male partners' depression, anxiety, problem alcohol use, and male-to-female physical and psychological IPV perpetration. The dependent variable was sexual IPV reported by female partners, measured at baseline, two years, and four years later. Covariates included age, income, marital status and educational level. We used a multi-group latent growth curve model (LGCM) to explain intercept, linear, and quadratic slopes, which represent the baseline, and linear and curvilinear trajectories of male-to-female sexual IPV, where groups were defined based on ethnicity. Results: Psychological IPV was associated with sexual IPV at baseline among both ethnic groups. The male partner's depression was a risk factor for an increase in sexual IPV over time among Black but not Hispanic women. Anxiety, problem alcohol use and physical IPV did not have an effect on the baseline or change in sexual IPV over time. Psychological IPV was not associated with an increase in sexual IPV over time in either ethnic groups. Conclusions: There is a need for screening of sexual IPV in the presence of psychological IPV among minority women. There is also a need for screening and treatment of male partners' depression as a strategy to reduce sexual IPV among Black women.

  20. Crossing the Color Line: Black Professional Men’s Development of Interracial Social Networks

    Directory of Open Access Journals (Sweden)

    Adia Harvey Wingfield

    2014-05-01

    Full Text Available Sociologists have established that social networks often play an important role in hiring, promotions, and occupational mobility. For black workers, however, social networks can be racialized in ways that work to their disadvantage. In this paper, I consider how black professional men develop and maintain interracial social networks with white men and women. I argue that these networks are shaped by intersections of race and gender and are intentionally constructed in response to black professional men’s perceptions of their positioning within male-dominated occupations. Specifically, this paper examines how black men establish social networks with white men, their perceptions of how diverging levels of social capital shape these networks compared to their white male peers, and their observations of ways that women are less advantaged than they are in constructing social networks.

  1. Education and black-white interracial marriage.

    Science.gov (United States)

    Gullickson, Aaron

    2006-11-01

    This article examines competing theoretical claims regarding how an individual's education will affect his or her likelihood of interracial marriage. I demonstrate that prior models of interracial marriage have failed to adequately distinguish the joint and marginal effects of education on interracial marriage and present a model capable of distinguishing these effects. I test this model on black-white interracial marriages using 1980, 1990, and 2000 U.S. census data. The results reveal partial support for status exchange theory within black male-white female unions and strong isolation of lower-class blacks from the interracial marriage market. Structural assimilation theory is not supported because the educational attainment of whites is not related in any consistent fashion to the likelihood of interracial marriage. The strong isolation of lower-class blacks from the interracial marriage market has gone unnoticed in prior research because of the failure of prior methods to distinguish joint and marginal effects.

  2. The transillumination technique as a method for the assessment of spermatogenesis using medicinal plants: the effect of extracts of black maca (Lepidium meyenii) and camu camu (Myrciaria dubia) on stages of the spermatogenic cycle in male rats.

    Science.gov (United States)

    Gonzales, Gustavo F; Vasquez, Vanessa Bertha; Gasco, Manuel

    2013-10-01

    Transillumination technique for assessment of stages of spermatogenic cycle is a useful tool for toxicological studies. This study was designed to determine the effect of two medicinal plants on spermatogenesis in male rats using the transillumination technique. For this, the effect of the combination of a fruit with highest content of ascorbic acid (Myrciaria dubia, camu camu) and extract of black maca (Lepidium meyenii) on seminiferous tubule stages scored by transillumination on intact tubules in adult male rats was assessed. Animals were treated during seven days with vehicle, black maca, camu camu or a mixture of black maca + camu camu and assessed for daily sperm production (DSP), stages of spermatogenic cycle as well as antioxidant activity and levels of flavonoids and polyphenols. Black maca increased stages of spermiation (VII-VIII) and mitosis of germ cells (IX-XI), whereas camu camu increased stages of mitosis (IX-XI) and meiosis (XII). Mixture of maca + camu camu increased stages of spermiation, mitosis and meiosis. All treatments increased DSP (pmaca. In conclusion, M. dubia (camu camu) has potential effects improving spermatogenesis and co-administered with maca increase stages of mitosis, meiosis and spermiation of the spermatogenic cycle as assessed by the transillumination technique. This technique is becoming increasingly a useful tool for assessment spermatogenesis.

  3. Carbon black nanoparticle exposure during middle and late fetal development induces immune activation in male offspring mice

    International Nuclear Information System (INIS)

    El-Sayed, Yasser S.; Shimizu, Ryuhei; Onoda, Atsuto; Takeda, Ken; Umezawa, Masakazu

    2015-01-01

    Increasing exposure to nanoparticles (NPs) has raised concerns regarding their health and safety profiles in humans and animals, especially in developing organisms, which may display increased sensitivity to NP toxicity. The present study examined the effects of gestational exposure to carbon black NP (CB-NP) on the development of the offspring immune system. Pregnant mice were exposed to CB-NP (95 μg/kg body weight) by intranasal instillation on gestational days 9 and 15. The thymus and spleen were collected from their offspring mice on postnatal day (PND) 1, 3 and 5. Thymocyte and splenocyte phenotypes were examined by determining the expression of cell-surface molecules using flow cytometry. Gene expression in the thymus and spleen was examined using quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Prenatal exposure to CB-NP increased total thymocytes and their immunophenotypes (CD4 − CD8 − and CD4 + CD8 + cells). It also induced an increase in total lymphocytes, and CD4 − CD8 − , particularly CD3 − B220 − cells, at PND 5 in the spleen of newborn male offspring, reflecting the stimulation of immature splenocytes. Furthermore, mRNA expression of genes related to the induction of peripheral tolerance (i.e. thymic Traf6) was upregulated. These data suggest that respiratory exposure to CB-NP during middle and late gestation may have allergic or inflammatory effects in male offspring, and may provide initial information on the potential developmental immunotoxicity of nanoparticles

  4. ‘This is the Age of Woman’: Black Feminism and Black Internationalism in the Works of Una Marson, 1928-1938

    Directory of Open Access Journals (Sweden)

    Imaobong D. Umoren

    2013-04-01

    Full Text Available Una Marson (1905-1965 was an Afro-Jamaican intellectual who in the 1930s became an internationally famous feminist, Pan-Africanist, poet, playwright, journalist and social activist. Between 1932 and 1936 Marson lived in London and became involved in the burgeoning Pan-African movement and a number of British and international women’s and feminist organisations. In 1936, she briefly returned to Jamaica amidst the nationalist movements of the time before journeying back to Britain in 1938, where she remained until 1946. This article builds on and differs from previous scholarship on Marson through its exploration of the changes that took place in her black feminist ideas relating to race, gender and class between 1928 and 1938, and how these influenced her intellectual view concerning black internationalism. This article puts two arguments forward. First, Marson’s engagement with Pan-Africanism and her experiences of racism and sexism in London changed her vision of black feminism. Second, this change contributed to her bringing black feminism into the male-dominated sphere of black internationalism. Thus, it calls for more recognition of Una Marson both as a black feminist and a black internationalist

  5. A New Business: Redirecting Black Youth from the Illegal Economy

    Science.gov (United States)

    Cox Edmondson, Vickie

    2009-01-01

    Young Black males are an at-risk group for earning a living through illegal activities in the U.S. As with most at-risk groups, concerted efforts have been made to help prepare them to become viable contributors and valued members of society. Anecdotal evidence shows that faculty members have also tried to reach out and influence young Black males…

  6. Cancer through black eyes - The views of UK based black men towards cancer: A constructivist grounded theory study.

    Science.gov (United States)

    Mulugeta, Betselot; Williamson, Susan; Monks, Rob; Hack, Thomas; Beaver, Kinta

    2017-08-01

    Little is known about black African (BA) and black African-Caribbean (BAC) men's views towards cancer; yet culture and acculturation can contribute to the way in which people understand, explain and develop their attitudes towards cancer. Hence, cancer prevention and early detection strategies may not be sensitive to United Kingdom (UK)-based black men's views, affecting their awareness of risk factors and early detection services. This study explored the views of UK-based BA and BAC men towards cancer. In collaboration with black community organisations based in four major cities in the UK, 25 participants were recruited using convenience and theoretical sampling methods. Data were collected using 33 semi-structured interviews, and analysed using grounded theory analytic procedures. One core category (cancer through black eyes) and seven sub-categories emerged; 'cultural views', 'religious beliefs', 'avoiding Babylon', 'alienation', 'suspicious mind', 'advertisements and information influence very little', and 'gap in service provision (bridging the gap)'. Participants' views towards cancer were linked to socially constructed perspectives, linked with cultural and religious beliefs, and shaped by what being a black male means in society. Risk factors such as smoking and obesity had different meanings and symbolisation through black eyes. There were macro- and micro-level similarities and differences between BA and BAC men. Cancer services and related public-health campaigns aimed at black men need to understand cancer through black eyes. Public health campaigns based solely on the clinical meaning of cancer are incongruent with black men's understandings of cancer, and therefore ineffective at reducing health inequality. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Black to Black

    DEFF Research Database (Denmark)

    Langkjær, Michael Alexander

    2012-01-01

    Pop musicians performing in black stage costume take advantage of cultural traditions relating to matters black. Stylistically, black is a paradoxical color: although a symbol of melancholy, pessimism, and renunciation, black also expresses minimalist modernity and signifies exclusivity (as is hi...

  8. Gender and Ethnic Differences in the Association Between Obesity and Depression Among Black Adolescents.

    Science.gov (United States)

    Assari, Shervin; Caldwell, Cleopatra Howard

    2015-12-01

    This study aimed to investigate the association between obesity and major depression disorder (MDD) in a nationally representative sample of Black adolescents in the USA. The study also tested the effects of ethnicity and gender as possible moderators. Data came from the National Survey of American Life (NSAL)-Adolescents, a representative household mental health survey of Black adolescents in the USA. Participants consisted of 1170 Black adolescents (810 African Americans and 360 Caribbean Blacks). Obesity was defined determined by the cutoff points based on the body mass index (BMI) appropriate for age and gender. Twelve-month MDD was measured using the World Mental Health Composite International Diagnostic Interview (CIDI). In the first step, the association between obesity and MDD in the pooled sample, controlling for the main effects of gender and ethnicity. In the next steps, two interactions were tested: (1) obesity and ethnicity and (2) obesity and gender. Although any associations between obesity and MDD in the pooled sample of Blacks were not found, there was a significant interaction between ethnicity and obesity on MDD. Upon testing the associations across intersections of ethnicity and gender, a positive association was found among Caribbean Black females but not Caribbean Black males, African American males, or African American female. The link between BMI and MDD among Blacks depends on ethnicity and gender, and risk of comorbid depression among Black youth with obesity is highest among Caribbean Black females.

  9. Sexual Stereotypes Ascribed to Black Men Who Have Sex with Men: An Intersectional Analysis.

    Science.gov (United States)

    Calabrese, Sarah K; Earnshaw, Valerie A; Magnus, Manya; Hansen, Nathan B; Krakower, Douglas S; Underhill, Kristen; Mayer, Kenneth H; Kershaw, Trace S; Betancourt, Joseph R; Dovidio, John F

    2018-01-01

    Sexual stereotypes may adversely affect the health of Black men who have sex with men (MSM). Greater understanding of the nature and nuances of these stereotypes is needed. This online, survey-based study used an inductive, intersectional approach to characterize the sexual stereotypes ascribed to Black MSM by the U.S. general public, their distinctiveness from those ascribed to Black men and MSM in general, and their relative prototypicality as compared to dominant subgroups. Members of the public, recruited in 2014-2015, were randomly assigned to survey conditions that varied systematically by race (Black, White, or unspecified) and sexual orientation (gay, heterosexual, or unspecified) of a designated social group. Participants (n = 285) reported stereotypes of their assigned group that they perceived to exist in U.S. culture in an open-response format. Cross-condition comparisons revealed that, overall, Black gay male stereotypes were non-prototypical of Black men or gay men. Rather, stereotypes of Black men were more similar to Black heterosexual men and stereotypes of gay men were more similar to White gay men. Nonetheless, 11 of the 15 most frequently reported Black gay male stereotypes overlapped with stereotypes of Black men (e.g., large penis), gay men (e.g., deviant), or both (e.g., promiscuous). Four stereotypes were unique relative to both Black men and gay men: down low, diseased, loud, and dirty. Findings suggest that Black MSM face multiple derogatory sexual stereotypes, several of which are group-specific. These stereotypes are consistent with cultural (mis)representations of Black MSM and suggest a need for more accurate portrayals of existing sexual diversity within this group.

  10. Understanding racial HIV/STI disparities in black and white men who have sex with men: a multilevel approach.

    Directory of Open Access Journals (Sweden)

    Patrick S Sullivan

    Full Text Available The reasons for black/white disparities in HIV epidemics among men who have sex with men have puzzled researchers for decades. Understanding reasons for these disparities requires looking beyond individual-level behavioral risk to a more comprehensive framework.From July 2010-December 2012, 803 men (454 black, 349 white were recruited through venue-based and online sampling; consenting men were provided HIV and STI testing, completed a behavioral survey and a sex partner inventory, and provided place of residence for geocoding. HIV prevalence was higher among black (43% versus white (13% MSM (prevalence ratio (PR 3.3, 95% confidence interval (CI: 2.5-4.4. Among HIV-positive men, the median CD4 count was significantly lower for black (490 cells/µL than white (577 cells/µL MSM; there was no difference in the HIV RNA viral load by race. Black men were younger, more likely to be bisexual and unemployed, had less educational attainment, and reported fewer male sex partners, fewer unprotected anal sex partners, and less non-injection drug use. Black MSM were significantly more likely than white MSM to have rectal chlamydia and gonorrhea, were more likely to have racially concordant partnerships, more likely to have casual (one-time partners, and less likely to discuss serostatus with partners. The census tracts where black MSM lived had higher rates of poverty and unemployment, and lower median income. They also had lower proportions of male-male households, lower male to female sex ratios, and lower HIV diagnosis rates.Among black and white MSM in Atlanta, disparities in HIV and STI prevalence by race are comparable to those observed nationally. We identified differences between black and white MSM at the individual, dyadic/sexual network, and community levels. The reasons for black/white disparities in HIV prevalence in Atlanta are complex, and will likely require a multilevel framework to understand comprehensively.

  11. African American Male Achievement: Using a Tenet of Critical Theory to Explain the African American Male Achievement Disparity

    Science.gov (United States)

    Palmer, Robert T.; Maramba, Dina C.

    2011-01-01

    Although African Americans continue to demonstrate a desire for education, Black male enrollment and completion rates in higher education are dismal when compared to other ethnic groups. Researchers and scholars have noted various theories and philosophies responsible for the academic disengagement of African American men in higher education. This…

  12. Diversity of Nuptial Plumages in Male Ruffs

    NARCIS (Netherlands)

    Van Rhijn, J.; Jukema, J.; Piersma, T.

    2014-01-01

    Nuptial ornament diversity was studied in 1814 individual male Ruffs that were caught in their spring staging areas in Friesland, The Netherlands. Ornaments (hereafter called plumages) comprised of a ruff, two head tufts and facial wattles. Individual feathers were found to be plain (white, black or

  13. Observations in infertile African males at an andrology clinic in South Africa.

    Science.gov (United States)

    Bornman, M S; Schulenburg, G W; Boomker, D; Chauke, T R; Reif, S

    1994-01-01

    The major cause of infertility among black Africans is traditionally attributed to a female factor and few reports are available on the male factor. This study analyzed the clinical and seminal data obtained from a population of 1726 suspected infertile African men evaluated from July 1985 to June 1991. The possible cause of infertility was judged on the results of first semen analysis. Of these men, 49% were secondarily infertile and 36% had previously received treatment for a urethral discharge. Varicocoeles were present in 183 cases (11%) and 11% had serological evidence of previous exposure to syphilis. Azoospermia was present in 152 patients (9%), 5% had polizoospermia, 45% had hypospermia ( 6 mL) had hyperspermia. In 70% of patients a possible contributing male factor for infertility was found. It would appear that the male factor contributed significantly to infertility, and evaluation of the black African male can therefore be regarded as a rewarding venture.

  14. Variability of resistance in Black Bengal goats naturally infected with Haemonchus contortus.

    Science.gov (United States)

    Kumar, Ratnesh; Ranjan, Sanjeev; Vishnu, P Guru; Negi, Mamta; Senapati, P K; Charita, V Gnani

    2015-03-01

    A total 290 Black Bengal goats (6 buck, 109 doe and 175 kids born from 11 sires) were studied to evaluate the variability of resistance in Black Bengal goats naturally infected with Haemonchus contortus. The variability of resistance in Black Bengal goat was studied for both genetic and non-genetic factors like village, sex, age dam, sire, dam resistance group and offspring resistance group. Male kids have slightly higher resistance than female kids although it was not significant. Resistance of kids was increased as age increases and kid population showed significantly different resistance status among the offspring resistant groups. The doe population showed significantly different LEPG as per the resistance group in all the collections. The present study found that the resistance of kids under sire were varied significantly and observed that the kids under sire 1, 6-8 were significantly more resistant than the kids of the sire 2, 5 and 11 in 3rd collection and it is also noticed that maternal genetic effect has a very little impact on resistance of kids. Males (buck) were most resistant and the kids were least resistant and the resistance of dam was in between the male and kids population.

  15. "They Think Minority Means Lesser than": Black Middle-Class Sons and Fathers Resisting Microaggressions in the School

    Science.gov (United States)

    Allen, Quaylan

    2013-01-01

    The current literature on Black middle-class men is sparse, leaving little to be known about the raced, classed, and gendered experiences for many Black middle-class male students and their families. Employing qualitative methodology, this study uses critical race theory (CRT) to examine the educational experiences of Black middle-class high…

  16. Do men need empowering too? A systematic review of entrepreneurial education and microenterprise development on health disparities among inner-city black male youth.

    Science.gov (United States)

    Jennings, Larissa

    2014-10-01

    Economic strengthening through entrepreneurial and microenterprise development has been shown to mitigate poverty-based health disparities in developing countries. Yet, little is known regarding the impact of similar approaches on disadvantaged U.S. populations, particularly inner-city African-American male youth disproportionately affected by poverty, unemployment, and adverse health outcomes. A systematic literature review was conducted to guide programming and research in this area. Eligible studies were those published in English from 2003 to 2014 which evaluated an entrepreneurial and microenterprise initiative targeting inner-city youth, aged 15 to 24, and which did not exclude male participants. Peer-reviewed publications were identified from two electronic bibliographic databases. A manual search was conducted among web-based gray literature and registered trials not yet published. Among the 26 papers retrieved for review, six met the inclusion criteria and were retained for analysis. None of the 16 registered microenterprise trials were being conducted among disadvantaged populations in the U.S. The available literature suggests that entrepreneurial and microenterprise programs can positively impact youth's economic and psychosocial functioning and result in healthier decision-making. Young black men specifically benefited from increased autonomy, engagement, and risk avoidance. However, such programs are vastly underutilized among U.S. minority youth, and the current evidence is insufficiently descriptive or rigorous to draw definitive conclusions. Many programs described challenges in securing adequate resources, recruiting minority male youth, and sustaining community buy-in. There is an urgent need to increase implementation and evaluation efforts, using innovative and rigorous designs, to improve the low status of greater numbers of African-American male youth.

  17. Sub-chronic indomethacin treatment and its effect on the male reproductive system of albino rats: possible protective role of black tea extract.

    Science.gov (United States)

    Bagoji, Ishwar B; Hadimani, Gavishiddappa A; Yendigeri, Saeed M; Das, Kusal K

    2017-05-01

    Indomethacin is commonly used as a nonsteroidal anti-inflammatory drug (NSAID) to treat inflammation, arthritis and joint pains. Unfortunately, it has a wide range of adverse effects on the physiological system, including gonads. This study aimed to assess possible beneficial effects of black tea extract (BTE) against indomethacin-induced alteration of gonadal hormone levels in male rats. Adult male rats were divided into Group I (control), Group II (indomethacin, 5 mg/kg body weight [bwt.]; i.p., 21 days), Group III (BTE, 2.5 g tea leaf/dL of water, i.e. 2.5% of aqueous BTE, orally, 21 days) and Group IV (indomethacin+BTE, 21 days). Sperm count and motility, serum luteinising hormone (LH), follicle-stimulating hormone (FSH) and testosterone, along with histopathology of testes were studied. One-way ANOVA, followed by post-hoc t-test were conducted. Indomethacin-treated rats showed significant decrease in testicular weight, sperm count, sperm motility, serum gonadotropins and testosterone concentrations. Histopathology of the testes showed tortuous and distorted seminiferous tubules, marked thickening of the tubular basement membrane, reduced spermatogenesis process (>30%) and marked decrease in the number of interstitial cells of Leydig in indomethacin-treated rats. Interestingly, rats supplemented with BTE showed remarkable improvements in testicular weight gain, sperm count and motility, serum gonadotropins and testosterone concentrations, along with testicular histopathology. The results suggest that BTE might have potential ameliorative effects against sub-chronic indomethacin-induced alteration of gonadal hormone levels in male albino rats.

  18. Neighborhood Safety and Major Depressive Disorder in a National Sample of Black Youth; Gender by Ethnic Differences

    Science.gov (United States)

    Assari, Shervin; Caldwell, Cleopatra Howard

    2017-01-01

    Adolescence is a developmental period marked by increased stress, especially among Black youth. In addition to stress related to their developmental transition, social factors such as a perceived unsafe neighborhood impose additional risks. We examined gender and ethnic differences in the association between perceived neighborhood safety and major depressive disorder (MDD) among a national sample of Black youth. We used data from the National Survey of American Life - Adolescents (NSAL-A), 2003–2004. In total, 1170 Black adolescents entered the study. This number was composed of 810 African American and 360 Caribbean Black youth (age 13 to 17). Demographic factors, perceived neighborhood safety, and MDD (Composite International Diagnostic Interview, CIDI) were measured. Logistic regressions were used to test the association between neighborhood safety and MDD in the pooled sample, as well as based on ethnicity by gender groups. In the pooled sample of Black youth, those who perceived their neighborhoods to be unsafe were at higher risk of MDD (Odds Ratio [OR] = 1.25; 95% Confidence Interval [CI] = 1.02-1.51). The perception that one’s neighborhood is unsafe was associated with a higher risk of MDD among African American males (OR=1.41; 95% CI = 1.03–1.93) but not African American females or Caribbean Black males and females. In conclusion, perceived neighborhood safety is not a universal psychological determinant of MDD across ethnic by gender groups of Black youth; however, policies and programs that enhance the sense of neighborhood safety may prevent MDD in male African American youth. PMID:28241490

  19. Adolescent males' orientation toward paternity and contraception.

    Science.gov (United States)

    Marsiglio, W

    1993-01-01

    Data from a nationally representative sample of 1,880 young men aged 15-19 reveal that neighborhood quality, parental education, race or ethnicity, and attitudes about male gender roles are related to young men's attitudes toward an unplanned pregnancy and to their contraceptive experiences. Young men who live in poor neighborhoods are more likely to be pleased about an unplanned pregnancy than those who have better living conditions (12% vs. 2%) and are also more likely to view impregnating a woman as enhancing their masculinity (8% vs. 3%). Among men with average living conditions, 12% of black adolescents view fathering a child as enhancing their masculinity, compared with 6% of white adolescents; among those with very good living conditions, these proportions were 10% and 2%, respectively. Young men whose parents had less education and those who held traditional male gender role attitudes were also more likely than their counterparts to view fathering a child as enhancing their masculinity. Regarding contraceptive behavior, sexually active black men and Hispanic men were more likely than white men to have discussed contraception with their last partner; black men were more likely to have used an effective contraceptive method the last time they had intercourse; and black men were more likely to have used a condom at last intercourse. However, young men who were aware that they had been responsible for a previous pregnancy were less likely than those who reported no pregnancies to have used an effective contraceptive the last time they had intercourse. These same young men were also more likely to report that fathering a child would please them and enhance their masculinity.

  20. Emasculation of male characters as seen through Sula by Toni Morrison

    Directory of Open Access Journals (Sweden)

    Ferdinand KPOHOUE

    2018-03-01

    Full Text Available Emasculation is a drawback of slavery as it was practiced in the Americas. Men are limited in their power in order to be exploited without strong reactions. This aspect appears in Sula where female characters play the main roles. Male characters are shaped to be absent, irresponsible or insane. Female characters take care of the household and fight for their own survival. Children are educated by the female characters, male characters are regularly absent, some of them have deserted the household. The objective of this paper is to explain, through the emasculation system, the behaviors of some male characters such as Shadrack, Plum Peace, BoyBoy, Jude and Ajax (Albert Jacks in Sula in order to provide deeper understanding to Toni Morrison’s skills to deal with the conditions of Blacks in the South of the USA.  This can help to understand more Sula which is deeply rooted in the black community with its traditions and realities.

  1. Leading Causes of Death Contributing to Decrease in Life Expectancy Gap Between Black and White Populations: United States, 1999-2013.

    Science.gov (United States)

    Kochanek, Kenneth D; Anderson, Robert N; Arias, Elizabeth

    2015-11-01

    Life expectancy at birth has increased steadily since 1900 to a record 78.8 years in 2013. But differences in life expectancy between the white and black populations still exist, despite a decrease in the life expectancy gap from 5.9 years in 1999 to 3.6 years in 2013. Differences in the change over time in the leading causes of death for the black and white populations have contributed to this decrease in the gap in life expectancy. Between 1999 and 2013, the decrease in the life expectancy gap between the black and white populations was mostly due to greater decreases in mortality from heart disease, cancer, HIV disease, unintentional injuries, and perinatal conditions among the black population. Similarly, the decrease in the gap between black and white male life expectancy was due to greater decreases in death rates for HIV disease, cancer, unintentional injuries, heart disease, and perinatal conditions in black males. For black females, greater decreases in diabetes death rates, combined with decreased rates for heart disease and HIV disease, were the major causes contributing to the decrease in the life expectancy gap with white females. The decrease in the gap in life expectancy between the white and black populations would have been larger than 3.6 years if not for increases in death rates for the black population for aortic aneurysm, Alzheimer’s disease, and maternal conditions. For black males, the causes that showed increases in death rates over white males were hypertension, aortic aneurysm, diabetes, Alzheimer’s disease, and kidney disease, while the causes that showed increases in death rates for black females were Alzheimer’s disease, maternal conditions, and atherosclerosis. This NCHS Data Brief is the second in a series of data briefs that explore the causes of death contributing to differences in life expectancy between detailed ethnic and racial populations in the United States. The first data brief focused on the racial differences in life

  2. Racial Discrimination during Adolescence Predicts Mental Health Deterioration in Adulthood: Gender Differences among Blacks.

    Science.gov (United States)

    Assari, Shervin; Moazen-Zadeh, Ehsan; Caldwell, Cleopatra Howard; Zimmerman, Marc A

    2017-01-01

    Despite the existing knowledge regarding the negative mental health consequences of perceived racial discrimination, very few researchers have used a longitudinal design with long-term follow-up periods to explore gender differences in this association over time. The current longitudinal study aimed to investigate gender differences in predictive role of an increase in perceived racial discrimination during adolescence for mental health deterioration a decade later when they are transitioning to young adulthood. Current study followed 681 Black youths for 18 years from 1994 (mean age 15) to 2012 (mean age 32). All participants spent their adolescence and transition to young adulthood in an economically disadvantaged urban area in the Midwest of the United States. Independent variable was perceived racial discrimination measured in 1999 and 2002. Outcomes were psychological symptoms (anxiety and depression) measured in 1999 and at end of follow-up (2012). Covariates included sociodemographics (age, family structure, and parental employment) measured in 1994. Gender was used to define groups in a multigroup structural equation model to test moderating effects. Multigroup structural equation modeling showed that among male Black youth, an increase in perceived racial discrimination from age 20 to 23 was predictive for an increase in symptoms of anxiety and depression from age 20 to 32. Among female Black youth, change in perceived racial discrimination did not predict future change in depressive or anxiety symptoms. While racial discrimination is associated with negative mental health consequences for both genders, male and female Black youth differ in regard to long-term effects of an increase in perceived discrimination on deterioration of psychological symptoms. Black males seem to be more susceptible than Black females to the psychological effects of an increase in racial discrimination over time.

  3. Racial Discrimination during Adolescence Predicts Mental Health Deterioration in Adulthood: Gender Differences among Blacks

    Directory of Open Access Journals (Sweden)

    Shervin Assari

    2017-05-01

    Full Text Available BackgroundDespite the existing knowledge regarding the negative mental health consequences of perceived racial discrimination, very few researchers have used a longitudinal design with long-term follow-up periods to explore gender differences in this association over time.ObjectiveThe current longitudinal study aimed to investigate gender differences in predictive role of an increase in perceived racial discrimination during adolescence for mental health deterioration a decade later when they are transitioning to young adulthood.MethodsCurrent study followed 681 Black youths for 18 years from 1994 (mean age 15 to 2012 (mean age 32. All participants spent their adolescence and transition to young adulthood in an economically disadvantaged urban area in the Midwest of the United States. Independent variable was perceived racial discrimination measured in 1999 and 2002. Outcomes were psychological symptoms (anxiety and depression measured in 1999 and at end of follow-up (2012. Covariates included sociodemographics (age, family structure, and parental employment measured in 1994. Gender was used to define groups in a multigroup structural equation model to test moderating effects.ResultsMultigroup structural equation modeling showed that among male Black youth, an increase in perceived racial discrimination from age 20 to 23 was predictive for an increase in symptoms of anxiety and depression from age 20 to 32. Among female Black youth, change in perceived racial discrimination did not predict future change in depressive or anxiety symptoms.ConclusionWhile racial discrimination is associated with negative mental health consequences for both genders, male and female Black youth differ in regard to long-term effects of an increase in perceived discrimination on deterioration of psychological symptoms. Black males seem to be more susceptible than Black females to the psychological effects of an increase in racial discrimination over time.

  4. Skeletal Myocyte Types and Vascularity in the Black Sicilian Pig

    OpenAIRE

    S. Velotto; E. Varricchio; M. R. Di Prisco; T. Stasi; A. Crasto

    2007-01-01

    The objective of this study was to verify the presence of giant fibres in the Black Sicilian pig skeletal muscle and to evaluate the effect of sex on histochemical and morphometric characteristics of the myocytes (myofibres) as well as vascularity of the muscle. Twenty Black Sicilian pigs (10 males, 10 females) from a farm in Sicily (Italy) were slaughtered at two years of age. Muscle tissues were obtained from three muscles: psoas major, longissimus dorsi, and trapezius. Myofibres were stain...

  5. "Deeper than Rap": Gifted Males and Their Relationship with Hip Hop Culture

    Science.gov (United States)

    Callahan, J. Sean; Grantham, Tarek C.

    2012-01-01

    One would be hard-pressed to deny the impact that hip hop is having on gifted students. More specifically, because hip hop is a creative and exciting male-dominated culture, gifted males gravitate to hip hop culture. From the perspective of two Black men from two different generations, this article was inspired by discussions about the role of hip…

  6. Looking for the invisible universe - Black matter, black energy, black holes

    International Nuclear Information System (INIS)

    Elbaz, David

    2016-01-01

    As the discovery of the expansion of the universe and of black holes put the study of cosmology into question again because it now refers to invisible things such as black holes, black energy and black matter, the author proposes an other view on the universe within such a context. He first discusses these three enigmas of black matter, black energy and black holes. In a second part, he addresses, discusses and comments five illusions: the Uranian illusion (questions of the existence of an anti-world, of black matter temperature), the Mercurian illusion (quantum gravity, the string theory), the Martian illusion (a patchwork universe, the illusion of the infinite), the cosmic Maya (the John Wheeler's cup, the holographic universe), and the narcissistic illusion

  7. Black South African freshmen's experience of first coitus and contraception.

    Science.gov (United States)

    Nicholas, L

    1994-01-01

    An anonymous questionnaire investigating Black South African first-year college students' experience of first intercourse and contraception was administered during the February 1993 orientation at a Black university. 754 females and 959 males of mean age 20.4 years in an age range of 16-50 years participated. 96.5% of the respondents were single. The study findings relate to the 894 single students who reported having experienced sexual intercourse. Male and female respondents' mean ages at first intercourse were, respectively, 15.5 and 17.8 years. 35.7% of males and 32.8% of females reported not using contraception during first intercourse, 12.3% of males and 7.1% of females were unsure, and 6.2% reported using withdrawal. 36.8% reported not using a condom because first sexual intercourse was unplanned, while 38.1% simply did not think about contraception at the time. Peers were reported as the primary first source of learning about sexual intercourse as well as the preferred source. These findings lend support to the need to target safer sex messages to college freshmen in this setting. In so doing, safer sex behavior can be encouraged and possibly adopted before high-risk sex behavior patterns develop.

  8. 'What does it take to be a man? What is a real man?': ideologies of masculinity and HIV sexual risk among Black heterosexual men.

    Science.gov (United States)

    Bowleg, Lisa; Teti, Michelle; Massie, Jenné S; Patel, Aditi; Malebranche, David J; Tschann, Jeanne M

    2011-05-01

    Research documents the link between traditional ideologies of masculinity and sexual risk among multi-ethnic male adolescents and White male college students, but similar research with Black heterosexual men is scarce. This exploratory study addressed this gap through six focus groups with 41 Black, low- to middle-income heterosexual men aged 19 to 51 years in Philadelphia, PA. Analyses highlighted two explicit ideologies of masculinity: that Black men should have sex with multiple women, often concurrently, and that Black men should not be gay or bisexual. Analyses also identified two implicit masculinity ideologies: the perception that Black heterosexual men cannot decline sex, even risky sex, and that women should be responsible for condom use. The study's implications for HIV prevention with Black heterosexual men are discussed. © 2011 Taylor & Francis

  9. The Crisis in Black and Black.

    Science.gov (United States)

    Hutchinson, Earl Ofari

    These essays explore why the historic conflict between blacks and whites in the United States has become a crisis that divides many African Americans. The changing racial dynamic is not marked by conflicts. between the black middle class and the poor, black men and women, the black intellectual elite and rappers, black politicians and the urban…

  10. The Tuskegee Syphilis Study, 1932 to 1972: Implications for HIV Education and AIDS Risk Education Programs in the Black Community.

    Science.gov (United States)

    Thomas, Stephen B.; Quinn, Sandra Crouse

    1991-01-01

    The Tuskegee study of untreated syphilis in black males caused distrust by blacks of the public health system that has implications for Acquired Immune Deficiency Syndrome (AIDS) and Human Immunodeficiency Virus (HIV) studies. AIDS prevention among blacks may require openness about the Tuskegee study to allay fears of repetition. (SLD)

  11. Hormone receptor expression in male breast cancers | Akosa ...

    African Journals Online (AJOL)

    Male breast cancers are rare but have been found in higher proportions in Black Africans. Prognostic factors for breast cancers include tumour size, grade and stage, and hormone receptor status. The hormone receptor status is an invaluable guide in the use of adjuvant endocrine therapy, but none of the reports available ...

  12. Influence of turmeric rhizome and black pepper on blood ...

    African Journals Online (AJOL)

    2012-04-26

    ) and black pepper. (BP) on blood components and performance of male broiler chickens. A 2 × 3 factorial arrangement with two levels of TRP (0 and 0.5 g/kg) and three levels of BP (0, 0.5 and 1 g/kg) were used to provide six.

  13. Patterns in Gut Microbiota Similarity Associated with Degree of Sociality among Sex Classes of a Neotropical Primate.

    Science.gov (United States)

    Amato, Katherine R; Van Belle, Sarie; Di Fiore, Anthony; Estrada, Alejandro; Stumpf, Rebecca; White, Bryan; Nelson, Karen E; Knight, Rob; Leigh, Steven R

    2017-07-01

    Studies of human and domestic animal models indicate that related individuals and those that spend the most time in physical contact typically have more similar gut microbial communities. However, few studies have examined these factors in wild mammals where complex social dynamics and a variety of interacting environmental factors may impact the patterns observed in controlled systems. Here, we explore the effect of host kinship and time spent in social contact on the gut microbiota of wild, black howler monkeys (Alouatta pigra). Our results indicate that closely related individuals had less similar gut microbial communities than non-related individuals. However, the effect was small. In contrast, as previously reported in baboons and chimpanzees, individuals that spent more time in contact (0 m) and close proximity (0-1 m) had more similar gut microbial communities. This pattern was driven by adult female-adult female dyads, which generally spend more time in social contact than adult male-adult male dyads or adult male-adult female dyads. Relative abundances of individual microbial genera such as Bacteroides, Clostridium, and Streptococcus were also more similar in individuals that spent more time in contact or close proximity. Overall, our data suggest that even in arboreal primates that live in small social groups and spend a relatively low proportion of their time in physical contact, social interactions are associated with variation in gut microbiota composition. Additionally, these results demonstrate that within a given host species, subgroups of individuals may interact with the gut microbiota differently.

  14. Eating attitudes, body image satisfaction and self-esteem of South African Black and White male adolescents and their perception of female body silhouettes.

    Science.gov (United States)

    Gitau, Tabither M; Micklesfield, Lisa K; Pettifor, John M; Norris, Shane A

    2014-01-01

    This cross-sectional study of urban high schools in Johannesburg, South Africa, sought to examine eating attitudes, body image and self-esteem among male adolescents (n = 391). Anthropometric measurements, Eating Attitudes Test-26 (EAT-26), Rosenberg self-esteem, body image satisfaction and perception of females were collected at age 13, 15 and 17 years. Descriptive analysis was done to describe the sample, and non-parametric Wilcoxon Mann-Whitney test was used to test for significant differences between data that were not normally distributed (EAT-26). Spearman's rank correlation coefficient analyses were conducted to test for associations between self-esteem scores and eating attitudes, body mass indices and body image satisfaction scores. To assess the differences between groups that were normally distributed chi-square tests were carried out. Ethnic differences significantly affected adolescent boys' body mass index (BMI), eating attitudes and self-esteem; White boys had higher self-esteem, BMI and normal eating attitudes than the Black boys did. BMI was positively associated with self-esteem (p = 0.01, r = 0.134) and negatively with dieting behaviour in White boys (p = 0.004, r = -0.257), and with lower EAT-26 bulimic and oral control scores in Black boys. In conclusion, the findings highlight ethnic differences and a need to better understand cultural differences that influence adolescent attitudes and behaviour.

  15. On Einstein's kinematics and his derivation of Lorentz transformation equations

    International Nuclear Information System (INIS)

    Gulati, Shobha; Gulati, S.P.

    1981-01-01

    Recently the present authors have claimed that Einstein's historic derivation of 1905 of Lorentz transformation equations is a 'howler' - a correct result achieved through some incorrect steps. In the present contribution, this howler is fully resolved. Incidently, Einstein's kinematical considerations are found to be void of any new definitional elements or conventionality as unjustifiably claimed by Einstein and some other scientists. (author)

  16. Sexual selection on male size drives the evolution of male-biased sexual size dimorphism via the prolongation of male development.

    Science.gov (United States)

    Rohner, Patrick T; Blanckenhorn, Wolf U; Puniamoorthy, Nalini

    2016-06-01

    Sexual size dimorphism (SSD) arises when the net effects of natural and sexual selection on body size differ between the sexes. Quantitative SSD variation between taxa is common, but directional intraspecific SSD reversals are rare. We combined micro- and macroevolutionary approaches to study geographic SSD variation in closely related black scavenger flies. Common garden experiments revealed stark intra- and interspecific variation: Sepsis biflexuosa is monomorphic across the Holarctic, while S. cynipsea (only in Europe) consistently exhibits female-biased SSD. Interestingly, S. neocynipsea displays contrasting SSD in Europe (females larger) and North America (males larger), a pattern opposite to the geographic reversal in SSD of S. punctum documented in a previous study. In accordance with the differential equilibrium model for the evolution of SSD, the intensity of sexual selection on male size varied between continents (weaker in Europe), whereas fecundity selection on female body size did not. Subsequent comparative analyses of 49 taxa documented at least six independent origins of male-biased SSD in Sepsidae, which is likely caused by sexual selection on male size and mediated by bimaturism. Therefore, reversals in SSD and the associated changes in larval development might be much more common and rapid and less constrained than currently assumed. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

  17. Brumation of introduced Black and White Tegus, Tupinambis merianae (Squamata: Teiidae), in southern Florida

    Science.gov (United States)

    McEachern, Michelle; Yackel Adams, Amy A.; Klug, Page E.; Fitzgerald, Lee A.; Reed, Robert N.

    2015-01-01

    An established population of Tupinambis merianae (Black and White Tegu) in southeastern Florida threatens the Everglades ecosystem. Understanding the behavioral ecology of Black and White Tegus could aid in management and control plans. Black and White Tegus are seasonally active and brumate during the winter in their native range, but brumation behavior is largely unstudied in either the native or the invasive range. We describe the first observations of Black and White Tegu brumation in southeastern Florida after monitoring 5 free-ranging, adult male Black and White Tegus through an inactive season using radiotelemetry and automated cameras. Duration of brumation averaged 137 days, beginning in September and ending by February. One of the 5 Black and White Tegus emerged to bask regularly during brumation, which to our knowledge represents the first documented instance of a free-ranging Black and White Tegu basking during brumation. These preliminary findings provide a basis for future research of brumation behavior.

  18. Responses of Neomegalotomus parvus (Hemiptera: Alydidae to color and male-lured traps

    Directory of Open Access Journals (Sweden)

    Maurício Ursi Ventura

    2004-08-01

    Full Text Available In 1998, the relative responses of Neomegalotomus parvus (Westwood (Hemiptera: Alydidae to colors in traps were assessed in the field. Colors were printed in white alkaline paper and covered with transparent plastic. Printed colors were black, green, yellow, red and blue. Treatments also included white paper and aluminum foil. Green traps captured more bugs than the other traps (except yellow. Yellow traps caught significantly more N. parvus males than blue, black and aluminum traps. White, red and blue traps captured significantly more N. parvus males than black traps. In 1999, the same treatments were used and additionally included the factor presence (X absence of males in cages in the traps. Four males were confined in the cages together with pigeon pea seeds and water. Control traps received only pigeon pea seeds and water. No responses were found for color comparisons. Male-lured traps captured significantly more males than control traps.Em 1998, as respostas relativas de Neomegalotomus parvus (Westwood (Hemiptera: Alydidae a cores em armadilhas foram avaliadas no campo. As cores foram impressas (preto, verde, amarelo, vermelho e azul, em papel alcalino branco e coberto com plástico transparente. Também se incluiu papel branco e folha de alumínio, como tratamentos. Armadilhas verdes capturaram mais insetos que outras armadilhas (exceto amarelo. Armadilhas amarelas capturaram significativamente mais machos de N. parvus do que armadilhas azuis, pretas e alumínio. Armadilhas brancas, vermelhas e azuis capturaram significativamente mais machos de N. parvus do que armadilhas pretas. Em 1999, os mesmos tratamentos foram usados e também se incluiu fator presença (X ausência de machos em gaiolas nas armadilhas. Quatro machos foram confinados nas gaiolas junto com sementes de guandu e água. Testemunhas receberam somente sementes de guandu e água. Não foram obtidas respostas significativas à cores. Armadilhas com machos capturaram

  19. Influence of turmeric rhizome and black pepper on blood ...

    African Journals Online (AJOL)

    ) and black pepper (BP) on blood components and performance of male broiler chickens. A 2 × 3 factorial arrangement with two levels of TRP (0 and 0.5 g/kg) and three levels of BP (0, 0.5 and 1 g/kg) were used to provide six dietary treatments ...

  20. Increasing Sex Mortality Differentials among Black Americans, 1950-1978.

    Science.gov (United States)

    Gee, Ellen M.; Veevers, Jean E.

    1985-01-01

    In regard to sex differentials in mortality among Blacks, explores (1) age groups responsible for increasing the differential, (2) causes of death that have contributed to the increased differential, and (3) whether the phenomenon derives from decreased female mortality, increased male mortality, or both rates moving in the same direction at…

  1. “What Does it Take to be a Man? What is a Real Man?”: Ideologies of masculinity and HIV sexual risk among Black heterosexual men

    Science.gov (United States)

    Bowleg, Lisa; Teti, Michelle; Massie, Jenné S.; Patel, Aditi; Malebranche, David J.; Tschann, Jeanne M.

    2011-01-01

    Research documents the link between traditional ideologies of masculinity and sexual risk among multi-ethnic male adolescents and White male college students, but similar research with Black heterosexual men is scarce. This exploratory study addressed this gap through six focus groups with 41 Black, low to middle income heterosexual men aged 19 to 51 years in Philadelphia, PA. Analyses highlighted two explicit ideologies of masculinity: that Black men should have sex with multiple women, often concurrently; and that Black men should not be gay or bisexual. Analyses also identified two implicit masculinity ideologies: the perception that Black heterosexual men cannot decline sex, even risky sex; and that women are primarily responsible for condom use. The study’s implications for HIV prevention with Black heterosexual men are discussed. PMID:21390949

  2. Gender Differences in African American Attitudes toward Gay Males.

    Science.gov (United States)

    Battle, Juan; Lemelle, Anthony J., Jr.

    2002-01-01

    Used data from the 1993 National Black Politics Study to examine the way gender worked in explaining African American attitudes toward gay men. Results indicated that African American females expressed more positive attitudes toward homosexual men than did African American males, and of the variables examined (including age, church attendance,…

  3. Fruit diet of Alouatta guariba and Brachyteles arachnoides in Southeastern Brazil: comparison of fruit type, color, and seed size.

    Science.gov (United States)

    Martins, Milene Moura

    2008-01-01

    Fruit is an important food resource for neotropical primates. In this study I compare the fruit diet of sympatric brown howlers (Alouatta guariba) and southern muriquis (Brachyteles arachnoides). Feeding behavior was studied over 12 months and fruit species consumed were identified and assigned to the categories fruit type, fruit color, and seed size. Observed-fruit feeding records were compared with expected records determined from local availability of the fruit of the tree species. I also determined dietary overlap. Fruit consumption occupied 8 and 12% of the feeding time of A. guariba and B. arachnoides, respectively. Fruit from eight tree species were consumed by the former and fruit from twenty-two species by the latter. Patterns of fruit selection of A. guariba and B. arachnoides varied widely. Although howlers and muriquis converge behaviorally by selecting fruit with common attributes (fleshy/unprotected, violet and brown/black-colored), unlike A. guariba, B. arachnoides fed on immature seeds of fleshy/protected and dry fruit. Large seeds were ingested, and defecated intact, by B. arachnoides only. There was little overlap of fruit diet even within categories that had been selected by both, suggesting that dietary divergence is occurring at the interspecific level. Different resource exploitation probably mediates the coexistence of A. guariba and B. arachnoides in low diversity, semideciduous forests, where the environment imposes narrow limits on primate food choices.

  4. The Effects of Chess Instruction on the Mathematics Achievement of Southern, Rural, Black Secondary Students.

    Science.gov (United States)

    Smith, James P.; Cage. Bob N.

    2000-01-01

    Studied the effects of 120 hours of chess instruction on the mathematics achievement of southern, rural, black secondary students. Analysis of covariance results show the treatment group (11 females, 9 males) scored significantly higher than the control group (10 females, 10 males) in mathematics achievement. Discusses results in terms of altering…

  5. A comparative study of central corneal thickness (CCT and intraocular pressure (IOP in University of KwaZulu-Natal students of Black and Indian ethnicity*

    Directory of Open Access Journals (Sweden)

    Z. Sardiwalla

    2012-12-01

    Full Text Available Thisstudy compared central corneal thickness (CCT and intraocular pressure (IOP of Black and Indian students from the University of Kwa-Zulu-Natal. Two hundred (100 Black and 100 Indi- an participants of both genders aged 18-25 years (mean and standard deviation; 20.1±1.6 years participated in this study. CCT and IOP were measured for the right eye of each participant using a Tono-Pachymeter (NT530P and a Goldmann applanation tonometer (GAT respectively. Data was analyzed with descriptive, t-test and Pearson’s cor-relation statistics. In the total sample (N = 200, the mean CCT value was 519.5 ± 38.6 μm and CCT was higher in the Indians (526.5 ± 37.2 µm than in the Blacks (512.4 ± 38.9 µm (p = 0.01.  Also, it was higher in the females (522.3 µm than in males (516.7 µm, but the difference was insignificant (p = 0.07. The mean CCT was higher in the Indian males (520.1 µm than in the Black males (513.2 µm, but the difference was insignificant (p=0.39.  However, it was significantly higher in the Indian females (533 µm than in the Black females (511.6 µm (p = 0.003. In the total sample, the mean IOP was 14.6 mmHg and IOP was greater in Indiansthan Blacks (mean = 15.3 ± 2.9 mmHg and 13.8 ± 2.6 mmHg respectively (p = 0.01. Also, the mean IOP (N = 200 value was slightly higher in the females (14.7 mmHg than in males (14.5 mmHg (p = 0.51. The mean IOP was higher in the Indian males (15.0 mmHg than in the Black males (14.0 mmHg (p = 0.07 and the mean IOP value was higher in the Indian females (15.7 mmHg than in the Black females (13.6 mmHg (p < 0.001. The higher mean IOP value in the Indian than Black participants was attributed to the higher mean CCT values. A positive, but inconsistent association between CCT and IOP was found in this study, the coefficient in the total sample (r = 0.382, p = 0.000, in the Blacks (r = 0.196, p = 0.05 and in Indians (r = 0.498, p = 0.000. A national population study comparing CCT and IOP in the various

  6. Men Do Matter: Ethnographic Insights on the Socially Supportive Role of the African American Uncle in the Lives of Inner-City African American Male Youth

    Science.gov (United States)

    Richardson, Joseph B., Jr.

    2009-01-01

    This article examines the role of the African American uncle as a vital yet overlooked form of social support and social capital in the lives of adolescent African American male sons living in single-female-headed households. Research rarely examines the affective roles and functions of men in Black families; moreover, poor urban Black male youth…

  7. Seed source, seed traits, and frugivore habits: Implications for dispersal quality of two sympatric primates.

    Science.gov (United States)

    Benítez-Malvido, Julieta; González-Di Pierro, Ana Ma; Lombera, Rafael; Guillén, Susana; Estrada, Alejandro

    2014-06-01

    • Premise of the study: Frugivore selection of fruits and treatment of seeds together with seed deposition site are crucial for the population dynamics of vertebrate-dispersed plants. However, frugivore species may influence dispersal quality differently even when feeding on the same fruit species and, while animals disperse some seeds, others simply fall beneath the parent plant.• Methods: In southern Mexico, we investigated to see if within-species seed traits (i.e., length, width, weight, and volume) and germination success differed according to seed source. For five tropical tree species we obtained ingested seeds from two sources, howler monkey (Alouatta pigra) and spider monkey (Ateles geoffroyi) feces; and noningested seeds from two sources, the ground and tree crowns (with predispersed seeds used as control).• Key results: A principal components' analysis showed that traits of seeds ingested by howler monkeys differed from other sources while seeds ingested by spider monkeys were similar to noningested seeds. Howlers consumed on average the larger seeds in Ampelocera hottlei, Brosimum lactescens, and Dialium guianense. Both primate species consumed the smaller seeds in Spondias mombin, while no seed trait differences among seed sources were found in Spondias radlkoferi. For all five tree species, germination rate was greatest for seeds ingested by howler monkeys.• Conclusions: For the studied plant species, seed ingestion by howler monkeys confers higher dispersal quality than ingestion by spider monkeys or nondispersal. Dispersal services of both primate species, however, are not redundant and may contribute to germination heterogeneity within plant populations in tropical forests. © 2014 Botanical Society of America, Inc.

  8. Corticosterone and time-activity budget: an experiment with Black-legged kittiwakes.

    Science.gov (United States)

    Angelier, Frédéric; Clément-Chastel, Céline; Gabrielsen, Geir Wing; Chastel, Olivier

    2007-11-01

    In vertebrates, the well established increase in plasma corticosterone in response to food shortage is thought to mediate adjustments of foraging behavior and energy allocation to environmental conditions. However, investigating the functional role of corticosterone is often constrained by the difficulty to track time-activity budget of free-ranging animals. To examine how an experimental increase in corticosterone affects the activity budget of male Black-legged kittiwakes (Rissa tridactyla), we used miniaturized activity loggers to record flying/foraging, presence on the sea surface and nest attendance. To investigate how corticosterone affects allocation processes between self-foraging and foraging devoted to the brood, we monitored body mass change of males from capture (day 0) to recapture (day 3). Among control birds, males in poor condition at day 0 spent significantly more time flying/foraging and less time attending the nest site than did males in good condition. Corticosterone treatment affected time spent flying/foraging in interaction with body condition at day 0: corticosterone-implanted males in good condition spent more time flying/foraging than control ones; this was not observed in poor condition males. In control birds, change in body mass was negatively correlated with body condition at day 0. This was reinforced by corticosterone treatment and, on average, corticosterone-implanted males gained much more mass than controls. These results suggest that in Black-legged kittiwakes, body condition and corticosterone levels can interact to mediate foraging decisions and possibly energy allocation: when facing stressful environmental conditions, birds in good body condition may afford to increase the time spent foraging probably to maintain brood provisioning, whereas poor body condition birds seemed rather to redirect available energy from reproduction to self-maintenance.

  9. Estimating grizzly and black bear population abundance and trend in Banff National Park using noninvasive genetic sampling.

    Directory of Open Access Journals (Sweden)

    Michael A Sawaya

    Full Text Available We evaluated the potential of two noninvasive genetic sampling methods, hair traps and bear rub surveys, to estimate population abundance and trend of grizzly (Ursus arctos and black bear (U. americanus populations in Banff National Park, Alberta, Canada. Using Huggins closed population mark-recapture models, we obtained the first precise abundance estimates for grizzly bears (N= 73.5, 95% CI = 64-94 in 2006; N= 50.4, 95% CI = 49-59 in 2008 and black bears (N= 62.6, 95% CI = 51-89 in 2006; N= 81.8, 95% CI = 72-102 in 2008 in the Bow Valley. Hair traps had high detection rates for female grizzlies, and male and female black bears, but extremely low detection rates for male grizzlies. Conversely, bear rubs had high detection rates for male and female grizzlies, but low rates for black bears. We estimated realized population growth rates, lambda, for grizzly bear males (λ= 0.93, 95% CI = 0.74-1.17 and females (λ= 0.90, 95% CI = 0.67-1.20 using Pradel open population models with three years of bear rub data. Lambda estimates are supported by abundance estimates from combined hair trap/bear rub closed population models and are consistent with a system that is likely driven by high levels of human-caused mortality. Our results suggest that bear rub surveys would provide an efficient and powerful means to inventory and monitor grizzly bear populations in the Central Canadian Rocky Mountains.

  10. Estimating grizzly and black bear population abundance and trend in Banff National Park using noninvasive genetic sampling.

    Science.gov (United States)

    Sawaya, Michael A; Stetz, Jeffrey B; Clevenger, Anthony P; Gibeau, Michael L; Kalinowski, Steven T

    2012-01-01

    We evaluated the potential of two noninvasive genetic sampling methods, hair traps and bear rub surveys, to estimate population abundance and trend of grizzly (Ursus arctos) and black bear (U. americanus) populations in Banff National Park, Alberta, Canada. Using Huggins closed population mark-recapture models, we obtained the first precise abundance estimates for grizzly bears (N= 73.5, 95% CI = 64-94 in 2006; N= 50.4, 95% CI = 49-59 in 2008) and black bears (N= 62.6, 95% CI = 51-89 in 2006; N= 81.8, 95% CI = 72-102 in 2008) in the Bow Valley. Hair traps had high detection rates for female grizzlies, and male and female black bears, but extremely low detection rates for male grizzlies. Conversely, bear rubs had high detection rates for male and female grizzlies, but low rates for black bears. We estimated realized population growth rates, lambda, for grizzly bear males (λ= 0.93, 95% CI = 0.74-1.17) and females (λ= 0.90, 95% CI = 0.67-1.20) using Pradel open population models with three years of bear rub data. Lambda estimates are supported by abundance estimates from combined hair trap/bear rub closed population models and are consistent with a system that is likely driven by high levels of human-caused mortality. Our results suggest that bear rub surveys would provide an efficient and powerful means to inventory and monitor grizzly bear populations in the Central Canadian Rocky Mountains.

  11. The effects of black garlic ethanol extract on the spatial memory and estimated total number of pyramidal cells of the hippocampus of monosodium glutamate-exposed adolescent male Wistar rats.

    Science.gov (United States)

    Hermawati, Ery; Sari, Dwi Cahyani Ratna; Partadiredja, Ginus

    2015-09-01

    Monosodium glutamate (MSG) is believed to exert deleterious effects on various organs, including the hippocampus, likely via the oxidative stress pathway. Garlic (Alium sativum L.), which is considered to possess potent antioxidant activity, has been used as traditional remedy for various ailments since ancient times. We have investigated the effects of black garlic, a fermented form of garlic, on spatial memory and estimated the total number of pyramidal cells of the hippocampus in adolescent male Wistar rats treated with MSG. Twenty-five rats were divided into five groups: C- group, which received normal saline; C+ group, which was exposed to 2 mg/g body weight (bw) of MSG; three treatment groups (T2.5, T5, T10), which were treated with black garlic extract (2.5, 5, 10 mg/200 g bw, respectively) and MSG. The spatial memory test was carried out using the Morris water maze (MWM) procedure, and the total number of pyramidal cells of the hippocampus was estimated using the physical disector design. The groups treated with black garlic extract were found to have a shorter path length than the C- and C+ groups in the escape acquisition phase of the MWM test. The estimated total number of pyramidal cells in the CA1 region of the hippocampus was higher in all treated groups than that of the C+ group. Based on these results, we conclude that combined administration of black garlic and MSG may alter the spatial memory functioning and total number of pyramidal neurons of the CA1 region of the hippocampus of rats.

  12. Make me wanna holler: Meshell Ndegeocello, Black queer aesthetics, and feminist critiques.

    Science.gov (United States)

    Richardson, Matt

    2014-01-01

    This article examines the music and performance of Meshell Ndegeocello, arguing that they are part of a cross-Atlantic conversation that pushes the boundaries of Black feminist thought on masculinity and desire. From the time of her debut album in 1993, Ndegeocello has resisted categorization both in her public personae and in her music. Ndegeocello's refusal to be restricted in her stage performance and in her musical expression has created a rich text through which to read Black female masculinity. Her work has been particularly productive in rethinking (Black) feminist couplings of patriarchy with male anatomy. Ndegeocello's music challenges any one representation of female masculinity, mixing critiques of masculine privilege and violence with celebrations of pleasure and pansexual desire.

  13. Gender, Mentoring Experiences, and Salary Attainment among Graduates of an Historically Black University.

    Science.gov (United States)

    Dreher, George F.; Chargois, Josephine A.

    1998-01-01

    Survey responses from 170 of 685 African-American graduates of historically Black colleges revealed no gender-based pay differences. Those who had White male mentors had some pay advantages over those without mentors. (SK)

  14. Sleep in healthy black and white adolescents.

    Science.gov (United States)

    Matthews, Karen A; Hall, Martica; Dahl, Ronald E

    2014-05-01

    Inadequate sleep among adolescents has negative consequences for self-regulation, emotional well-being, and risk behaviors. Using multiple assessment methods, we evaluated the adequacy of sleep among healthy adolescents from a lower socioeconomic community and expected differences by race. A total of 250 healthy high school students enrolled in public school (mean age: 15.7 years; 57% black, 54% female) from families of low to middle class according to the Hollingshead scale participated in weeklong assessments of sleep duration and fragmentation, assessed by using actigraphy; sleep duration and perceived quality, assessed by using daily diaries; and daytime sleepiness and sleep delay, assessed by using a questionnaire. Students slept during the school week a mean ± SD of 6.0 ± 0.9 hours per night according to actigraphy and 6.8 ± 1.1 hours according to daily diary, and during the weekend, a mean of 7.4 ± 1.2 and 8.7 ± 1.4 hours, respectively. Black participants and male participants slept less and had more fragmented sleep; female participants reported poorer quality of sleep in their daily diaries and more daytime sleepiness. The results remained significant after adjustments for age, physical activity, smoking status, and percentile BMI. Most students slept less than the 8 to 9 hours suggested by the guidelines of the Centers for Disease Control and Prevention. Black male participants had the least amount of sleep, which may play a role in the substantial risks experienced by this demographic group. Our findings are consistent with recommendations that pediatricians should routinely screen their adolescent patients about their sleep, especially those from at-risk subgroups. Copyright © 2014 by the American Academy of Pediatrics.

  15. Black Silicon Solar Cells with Black Ribbons

    DEFF Research Database (Denmark)

    Davidsen, Rasmus Schmidt; Tang, Peter Torben; Mizushima, Io

    2016-01-01

    We present the combination of mask-less reactive ion etch (RIE) texturing and blackened interconnecting ribbons as a method for obtaining all-black solar panels, while using conventional, front-contacted solar cells. Black silicon made by mask-less reactive ion etching has total, average...... in the range 15.7-16.3%. The KOH-textured reference cell had an efficiency of 17.9%. The combination of black Si and black interconnecting ribbons may result in aesthetic, all-black panels based on conventional, front-contacted silicon solar cells....... reflectance below 0.5% across a 156x156 mm2 silicon (Si) wafer. Black interconnecting ribbons were realized by oxidizing copper resulting in reflectance below 3% in the visible wavelength range. Screen-printed Si solar cells were realized on 156x156 mm2 black Si substrates with resulting efficiencies...

  16. Characterization of breeding habitats for black and surf scoters in the eastern boreal forest and subarctic regions of Canada

    Science.gov (United States)

    Perry, M.C.; Kidwell, D.M.; Wells, A.M.; Lohnes, E.J.R.; Osenton, P.C.; Altmann, S.H.; Hanson, Alan; Kerekes, Joseph; Paquet, Julie

    2006-01-01

    We analyzed characteristics of wetland habitats used by breeding black scoters (Melanitta nigra) and surf scoters (M. perspicillata) in the eastern boreal forest and subarctic regions of Canada based on satellite telemetry data collected in the spring and summer. During 2002 and 2004, nine black scoters (four males, five females) were tracked to breeding areas in Quebec, Manitoba, and Northwest Territories. In addition, in 2001?04, seven surf scoters (three males, four females) were tracked to breeding areas in Labrador, Quebec, Northwest Territories, and Nunavut. Based on satellite telemetry data, locations of black and surf scoters in breeding areas were not significantly different in regard to latitude and longitude. Presumed breeding areas were manually plotted on topographic maps and percent cover type and water were estimated. Breeding habitat of black scoters was significantly different than that for surf scoters, with black scoters mainly using open (tundra) areas (44%) and surf scoters using mainly forest areas (66%). Surf scoters presumed breeding areas were at significantly higher elevations than areas used by black scoters. Some breeding areas were associated with islands, but the role of islands for breeding areas is equivocal. These results aid in the identification of potentially critical breeding areas and provide a baseline classification of breeding habitats used by these two species.

  17. CARDIOTHORACIC RATIO AND VERTEBRAL HEART SCALE IN CLINICALLY NORMAL BLACK-RUMPED AGOUTIS (DASYPROCTA PRYMNOLOPHA, WAGLER 1831).

    Science.gov (United States)

    de Moura, Charlys Rhands Coelho; das Neves Diniz, Anaemilia; da Silva Moura, Laecio; das Chagas Araújo Sousa, Francisco; Baltazar, Pollyana Irene; Freire, Larisse Danielle; Guerra, Porfírio Candanedo; de Sousa, João Macedo; Giglio, Robson Fortes; Pessoa, Gerson Tavares; de Sá, Renan Paraguassu; Alves, Flávio Ribeiro

    2015-06-01

    Wild rodents, such as the lowland paca (Cuniculus paca), capybara (Hydrochoerus hydrochaeris), rock cavy (Kerodon rupestris), guinea pig (Cavia aperea), and black-rumped agouti (Dasyprocta prymnolopha) are intensely hunted throughout Amazonia and at the semiarid regions of northeastern Brazil. To contribute to the preservation of these species, more information about their anatomy, physiology and pathophysiology is needed. The aim of this study was to standardize the vertebral heart scale (VHS) and cardiothoracic ratio (CTR) in clinically normal black-rumped agouti, as well as to compare the results of these two methods, which are commonly used to evaluate the cardiac silhouette in domestic animals. Twelve healthy black-rumped agoutis, divided into two groups (six males and six females), obtained from the Nucleus for Wild Animal Studies and Conservation at the Federal University of Piauí, were radiographed in right and left lateral and dorsoventral projections. The values of the VHS were 8.00±0.31v (the number of thoracic vertebral length spanned by each dimension, starting at T4) for males and 8.11±0.41v for females, and there was no statistical difference between the decubitus (right and left) or between males and females (P>0.05). The CTR mean values obtained were 0.51±0.03 for males, and 0.52±0.02 for females, and there was no statistical difference between the genders (P>0.05). However, there was positive correlation between VHS and CTR (r=0.77 right decubitus and r=0.82 left decubitus). The thoracic and heart diameter had mean values of 6.72±0.61 and 3.48±0.30 cm (males), and for the females, it was 6.61±0.51 and 3.5±0.30 cm, respectively, and there was statistical difference between the genders. The results demonstrated high correlation between the VHS and CTR producing similar results, indicating similar clinical precision for assessing the size of the cardiac silhouette in the black-rumped agoutis.

  18. Juodosios moters savikūra Gayl Jones romane Evos vyras | Black Woman’s Self-Creation in Gayl Jones’s Novel Eva’s Man

    Directory of Open Access Journals (Sweden)

    Rasa Juozapaitytė

    2005-01-01

    Full Text Available The paper analyses the discourse of the black narrator and protagonist – Eva in Gayl Jones’s novel Eva’s Man. The French feminist theory of l’écriture féminine with its emphasis on textuality of gender has been applied to prove that the Afro-American woman creates her Self while writing and her text becomes the essence of her identity since any other opportunity of emotional, intellectual and spiritual evolution has been denied to her. It is explained that the black woman revolves against the boundaries of the hierarchical system, into which she had been placed, silenced and transformed into an object of male manipulation. The analysis of the novel suggests that the liberation of the black woman from the male construct coincides with the progress of her self-creation. Eva disrupts the rationalistic discourse, subverts the phallologocentric order, and establishes a dialogue of gap and silence. The black narrator’s text transforms the traditional canon of woman as ground, her body as the blank page and subjugates the black male body to secure her ciphers on it as her own text. It has been stressed that the woman’s conscious conversion into the subject and the creator enables her to translate the man into the object.

  19. High risk of metabolic syndrome among black South African women with severe mental illness

    Directory of Open Access Journals (Sweden)

    Shamima Saloojee

    2017-04-01

    Full Text Available Background: There is an increased prevalence of metabolic syndrome (MetS in individuals with severe mental illness (SMI globally. The prevalence of MetS is higher in black women compared to black men from South Africa. Aim: To compare the prevalence of MetS between black South African men and women with SMI taking antipsychotic medication. Further, this prevalence was compared to the prevalence in a matched control group of black South African men and women without SMI. Setting: A general hospital psychiatric unit. Methods: A cross-sectional study was undertaken to compare the prevalence of MetS in a group of multi-ethnic participants with SMI treated with antipsychotic medication and a matched control group without SMI, applying the 2009 Joint Interim Statement (JIS criteria. Here, we included only the black African participants to compare MetS prevalence between men and women. Results: There were 232 participants in the group with SMI (male 155 and female 77 and without SMI (male 156 and female 76. The prevalence of MetS was more than three times higher in women with SMI compared to men with SMI (37.7% vs. 10.3%, p < 0.001. There was no significant difference in the prevalence of MetS in men or women between the groups with and without SMI. In multivariate logistic regression analysis, female gender (odds ratio [OR] 7.66, advancing age (OR 1.08 and longer duration of illness (OR = 1.15 were significant risk factors for MetS in SMI. Conclusion: In black South Africans with SMI on antipsychotic medication, there is a higher prevalence and risk for MetS in women compared to men.

  20. Food availability and foraging near human developments by black bears

    Science.gov (United States)

    Merkle, Jerod A.; Robinson, Hugh S.; Krausman, Paul R.; Alaback, Paul B.

    2013-01-01

    Understanding the relationship between foraging ecology and the presence of human-dominated landscapes is important, particularly for American black bears (Ursus americanus), which sometimes move between wildlands and urban areas to forage. The food-related factors influencing this movement have not been explored, but can be important for understanding the benefits and costs to black bear foraging behavior and the fundamental origins of bear conflicts. We tested whether the scarcity of wildland foods or the availability of urban foods can explain when black bears forage near houses, examined the extent to which male bears use urban areas in comparison to females, and identified the most important food items influencing bear movement into urban areas. We monitored 16 collared black bears in and around Missoula, Montana, during 2009 and 2010, while quantifying the rate of change in green vegetation and the availability of 5 native berry-producing species outside the urban area, the rate of change in green vegetation, and the availability of apples and garbage inside the urban area. We used parametric time-to-event models in which an event was a bear location collected within 100 m of a house. We also visited feeding sites located near houses and quantified food items bears had eaten. The probability of a bear being located near a house was 1.6 times higher for males, and increased during apple season and the urban green-up. Fruit trees accounted for most of the forage items at urban feeding sites (49%), whereas wildland foods composed fruit trees, appear to be more important than the availability of garbage in influencing when bears forage near houses.

  1. Relationship power and HIV risk among young Black men who have sex with men in the Southern United States.

    Science.gov (United States)

    Ricks, JaNelle M; Crosby, Richard A; Mena, Leandro

    2018-05-01

    Background: The purpose of this study was to examine the impact of relationship power on HIV risk behaviour among young Black men who have sex with men (MSM) in the Southern US. Methods: Data from 425 Black/African American males aged 18-29 years who reported recent anal intercourse with a male partner were analysed. Five selected measures of relationship power were tested for correlation and association with protected receptive anal intercourse using contingency tables and logistic regression analysis. Results: Acts of 100% protected receptive anal intercourse were common (n=277, 65.2%). Men who reported low barriers to condom negotiation were significantly more likely to report protected acts (P<0.001). Men who reported 100% protected acts were less likely to report financial dependence on male sexual partners and serosorting behaviour (12.0% vs 20.7%, P=0.02; 31.5% vs 49.8%, P<0.001 respectively). Conclusion: Future efforts should further examine the role of relationship power in HIV risk among young Black MSM, including the intersection of individual, dyadic and social-structure risks.

  2. Cost-effectiveness of newborn circumcision in reducing lifetime HIV risk among U.S. males.

    Directory of Open Access Journals (Sweden)

    Stephanie L Sansom

    Full Text Available BACKGROUND: HIV incidence was substantially lower among circumcised versus uncircumcised heterosexual African men in three clinical trials. Based on those findings, we modeled the potential effect of newborn male circumcision on a U.S. male's lifetime risk of HIV, including associated costs and quality-adjusted life-years saved. METHODOLOGY/PRINCIPAL FINDINGS: Given published estimates of U.S. males' lifetime HIV risk, we calculated the fraction of lifetime risk attributable to heterosexual behavior from 2005-2006 HIV surveillance data. We assumed 60% efficacy of circumcision in reducing heterosexually-acquired HIV over a lifetime, and varied efficacy in sensitivity analyses. We calculated differences in lifetime HIV risk, expected HIV treatment costs and quality-adjusted life years (QALYs among circumcised versus uncircumcised males. The main outcome measure was cost per HIV-related QALY saved. Circumcision reduced the lifetime HIV risk among all males by 15.7% in the base case analysis, ranging from 7.9% for white males to 20.9% for black males. Newborn circumcision was a cost-saving HIV prevention intervention for all, black and Hispanic males. The net cost of newborn circumcision per QALY saved was $87,792 for white males. Results were most sensitive to the discount rate, and circumcision efficacy and cost. CONCLUSIONS/SIGNIFICANCE: Newborn circumcision resulted in lower expected HIV-related treatment costs and a slight increase in QALYs. It reduced the 1.87% lifetime risk of HIV among all males by about 16%. The effect varied substantially by race and ethnicity. Racial and ethnic groups who could benefit the most from circumcision may have least access to it due to insurance coverage and state Medicaid policies, and these financial barriers should be addressed. More data on the long-term protective effect of circumcision on heterosexual males as well as on its efficacy in preventing HIV among MSM would be useful.

  3. Hair penalties: The negative influence of Afrocentric hair on ratings of Black women's dominance and professionalism.

    Directory of Open Access Journals (Sweden)

    Tina R. Opie

    2015-08-01

    Full Text Available Purpose: Women are penalized if they do not behave in a stereotype-congruent manner (Eagly & Carli, 2007; Heilman, 1983; 2001. For example, because women are not expected to be agentic they incur an agency penalty for expressing anger, dominance or assertiveness (Brescoll & Uhlmann, 2008; Eagly & Karau, 2002; Livingston, Rosette, & Washington, 2012; Rudman, 1998; Rudman & Fairchild, 2004; Rudman & Glick, 1999, 2001. Yet, all women are not equally penalized (Livingston, Rosette, & Washington, 2012. We make a novel contribution by examining how both White and Black evaluators respond to Black women’s dominance, in this case, whether Black women choose to wear Afrocentric or Eurocentric hairstyles. Design/methodology/approach: We conducted three experimental studies to examine the influence of target hairstyle and participant race on ratings of the target’s professionalism (Studies 1, 2 and 3 and dominance (Study 2. Study 1 was an online experimental study with 200 participants (112 females, 87 males, 1 missing gender; 160 Whites, 19 Blacks, 11 Latinos, 7 Asian Americans and 3 who identify as other; Mage= 35.5, SD = 11.4. Study 2 was an online experimental study with 510 participants (276 women, 234 males; 256 Blacks, 254 Whites; Mage = 41.25 years, SD = 12.21. Study 3 was an online experimental study with 291 participants (141 Blacks, 150 Whites, Mage= 47.5 years, SD = 11.66. Findings: Black, as compared to White, evaluators gave higher agency penalties to Black employment candidates when they donned Afrocentric versus Eurocentric hair, rating them as more dominant and less professional. Implications: The present research illustrates the significance of considering both target and evaluator race when examining the influence of agency, and specifically dominance, on ratings of professionalism.

  4. Black holes

    International Nuclear Information System (INIS)

    Feast, M.W.

    1981-01-01

    This article deals with two questions, namely whether it is possible for black holes to exist, and if the answer is yes, whether we have found any yet. In deciding whether black holes can exist or not the central role in the shaping of our universe played by the forse of gravity is discussed, and in deciding whether we are likely to find black holes in the universe the author looks at the way stars evolve, as well as white dwarfs and neutron stars. He also discusses the problem how to detect a black hole, possible black holes, a southern black hole, massive black holes, as well as why black holes are studied

  5. Black silicon with black bus-bar strings

    DEFF Research Database (Denmark)

    Davidsen, Rasmus Schmidt; Tang, Peter Torben; Mizushima, Io

    2016-01-01

    We present the combination of black silicon texturing and blackened bus-bar strings as a potential method for obtaining all-black solar panels, while using conventional, front-contacted solar cells. Black silicon was realized by mask-less reactive ion etching resulting in total, average reflectance...... below 0.5% across a 156x156 mm2 silicon wafer. Black bus-bars were realized by oxidized copper resulting in reflectance below 3% in the entire visible wavelength range. The combination of these two technologies may result in aesthetic, all-black panels based on conventional, front-contacted solar cells...

  6. Lead exposure in adult males in urban Transvaal Province, South Africa during the apartheid era.

    Science.gov (United States)

    Hess, Catherine A; Cooper, Matthew J; Smith, Martin J; Trueman, Clive N; Schutkowski, Holger

    2013-01-01

    Human exposure to lead is a substantial public health hazard worldwide and is particularly problematic in the Republic of South Africa given the country's late cessation of leaded petrol. Lead exposure is associated with a number of serious health issues and diseases including developmental and cognitive deficiency, hypertension and heart disease. Understanding the distribution of lifetime lead burden within a given population is critical for reducing exposure rates. Femoral bone from 101 deceased adult males living in urban Transvaal Province (now Gauteng Province), South Africa between 1960 and 1998 were analyzed for lead concentration by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Of the 72 black and 29 white individuals sampled, chronic lead exposure was apparent in nearly all individuals. White males showed significantly higher median bone lead concentration (ME = 10.04 µg·g(-1)), than black males (ME = 3.80 µg·g(-1)) despite higher socioeconomic status. Bone lead concentration covaries significantly, though weakly, with individual age. There was no significant temporal trend in bone lead concentration. These results indicate that long-term low to moderate lead exposure is the historical norm among South African males. Unexpectedly, this research indicates that white males in the sample population were more highly exposed to lead.

  7. Effects of playing a violent video game as male versus female avatar on subsequent aggression in male and female players.

    Science.gov (United States)

    Yang, Grace S; Huesmann, L Rowell; Bushman, Brad J

    2014-01-01

    Previous research has shown that violent video games can increase aggression in players immediately after they play. The present research examines the effects of one subtle cue within violent video games that might moderate these effects-whether the avatar is male or female. One common stereotype is that males are more aggressive than females. Thus, playing a violent video game as a male avatar, compared to a female avatar, should be more likely to prime aggressive thoughts and inclinations in players and lead to more aggressive behavior afterwards. Male and female university students (N = 242) were randomly assigned to play a violent video game as a male or female avatar. After gameplay, participants gave an ostensible partner who hated spicy food hot sauce to eat. The amount of hot sauce given was used to measure aggression. Consistent with priming theory, results showed that both male and female participants who played a violent game as a male avatar behaved more aggressively afterwards than those who played as female avatar. The priming effects of the male avatar were somewhat stronger for male participants than for female participants, suggesting that male participants identified more with the male avatar than did the female participants. These results are particularly noteworthy because they are consistent with another recent experiment showing that playing a violent game as an avatar with a different stereotypically aggressive attribute (black skin color) stimulates more aggression than playing as an avatar without the stereotypically aggressive attribute (Yang et al., 2014, Social Psychological and Personality Science). © 2014 Wiley Periodicals, Inc.

  8. Factors associated with leisure time physical inactivity in black individuals: hierarchical model

    Directory of Open Access Journals (Sweden)

    Francisco José Gondim Pitanga

    2014-09-01

    Full Text Available Background. A number of studies have shown that the black population exhibits higher levels of leisure-time physical inactivity (LTPI, but few have investigated the factors associated with this behavior.Objective. The aim of this study was to analyze associated factors and the explanatory model proposed for LTPI in black adults.Methods. The design was cross-sectional with a sample of 2,305 adults from 20–96 years of age, 902 (39.1% men, living in the city of Salvador, Brazil. LTPI was analyzed using the International Physical Activity Questionnaire (IPAQ. A hierarchical model was built with the possible factors associated with LTPI, distributed in distal (age and sex, intermediate 1 (socioeconomic status, educational level and marital status, intermediate 2 (perception of safety/violence in the neighborhood, racial discrimination in private settings and physical activity at work and proximal blocks (smoking and participation in Carnival block rehearsals. We estimated crude and adjusted odds ratio (OR using logistic regression.Results. The variables inversely associated with LTPI were male gender, socioeconomic status and secondary/university education, although the proposed model explains only 4.2% of LTPI.Conclusions. We conclude that male gender, higher education and socioeconomic status can reduce LTPI in black adults.

  9. Institutional Identity and Self-Esteem among African American Males in College

    Science.gov (United States)

    Thomas, Dominique L.; Smith, Chauncey D.; Marks, Bryant T.; Crosby, Brandon

    2012-01-01

    Social identity theory maintains that one's self-concept is partially determined by the social groups to which the individual belongs. Using this as a theoretical framework, this study examined the relationship between multiple dimensions of institutional identity and self-esteem in 411 Black male college freshmen. It was hypothesized that…

  10. Black rings

    International Nuclear Information System (INIS)

    Emparan, Roberto; Reall, Harvey S

    2006-01-01

    A black ring is a five-dimensional black hole with an event horizon of topology S 1 x S 2 . We provide an introduction to the description of black rings in general relativity and string theory. Novel aspects of the presentation include a new approach to constructing black ring coordinates and a critical review of black ring microscopics. (topical review)

  11. "Black Like Me": Reframing Blackness for Decolonial Politics

    Science.gov (United States)

    Dei, George J. Sefa

    2018-01-01

    From a particular vantage point, as an African-born scholar with a politics to affirm my Black subjectivity and Indigeneity in a diasporic context, my article engages a (re)theorization of Blackness for decolonial politics. Building on existing works of how Black scholars, themselves, have theorized Blackness, and recognizing the fluid,…

  12. Temporal trends in cardiovascular disease risk factors among white, South Asian, Chinese and black groups in Ontario, Canada, 2001 to 2012: a population-based study.

    Science.gov (United States)

    Chiu, Maria; Maclagan, Laura C; Tu, Jack V; Shah, Baiju R

    2015-08-10

    To determine ethnic-specific temporal trends in cardiovascular risk factors in Ontario between 2001 and 2012. A population-based repeated cross-sectional study. Ontario, Canada. 219,276 participants of the Canadian Community Health Survey (205,326 white, 5620 South Asian, 4368 Chinese and 3962 black) during the period 2001 to 2012. Age-standardised ethnic-sex-specific prevalence of cardiovascular risk factors for three time periods: 2001-2004, 2005-2008 and 2009-2012 among Canada's four major ethnic groups: white, South Asian, Chinese and black. During the study period, the prevalence of diabetes increased 2.3-fold (p = 0.0001) among South Asian males and 1.9-fold (p = 0.02) among black females. The prevalence of obesity (body mass index ≥ 30 kg/m(2)) increased over time across all ethnic groups, with the largest relative increases observed among males of Chinese (2.1-fold increase, p = 0.04) and black (1.7-fold increase, p = 0.06) descent. The prevalence of hypertension increased the most among black females. Smoking prevalence decreased by more than 20% among South Asian, Chinese and white females. Overall, South Asian males and black males and females showed the greatest declines in cardiovascular health over the study period. We observed important ethnic differences in the temporal trends in cardiovascular risk factor profiles in Ontario. Awareness of the direction and magnitude of these risk factor trends may be useful in informing targeted strategies for preventing cardiovascular diseases in multiethnic populations. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  13. Mating success of males with and without wing patch in Drosophila biarmipes.

    Science.gov (United States)

    Hegde, S N; Chethan, B K; Krishna, M S

    2005-10-01

    Some males of D. biarmipes--synonym of D. rajasekari and D. raychaudhuri have a black patch on the wing. The patch extends from the apical margin of wing to the third longitudinal vein. Field and laboratory studies have been carried out in D. biarmipes to study role of male's wing patch in mating success. The field study shows that nature favors D. biarmipes males with patch. Although males without patch mated, males with patch have higher mating success suggesting the role of wing patch during courtship. Further, among mating males, males with patch had longer wings than males without patch. During courtship, males with patch oriented and mated faster; performed courtship acts such as tapping, scissoring, vibration, licking and twist dance more times than males without patch in both competitive and non-competitive situations. The results indicate that there is a casual relationship between the presence of wing patch, mating speed and success. Also there is a correlation between presence of wing patch, size of the flies and mating success.

  14. Habitats used by black and surf scoters in eastern North America as determined by satellite radio telemetry

    Science.gov (United States)

    Perry, M.C.; Kidwell, D.M.; Wells-Berlin, A. M.; Lohnes, E.J.R.; Olsen, Glenn H.; Osenton, P.C.

    2005-01-01

    Satellite radio telemetry was used to determine the movements and habitats of black scoters (Melanitta nigra) and surf scoters (Melanitta perspicillata) in eastern North America. A total of 21 surf scoters were instrumented during five years (2001-05) and 32 black scoters were instrumented during three years (2002-04) with implanted PTT 100 satellite transmitters (39 g) with external antenna. Nesting habitat of black scoters was more open than surf scoters (44% vs. 11%), whereas nesting habitat for surf scoters was located in more forested areas (66% vs. 20%). Locations of black scoters in breeding areas on average were at significantly higher latitude and lower elevations than sites used by surf scoters. Satellite telemetry determined that James Bay was the major molting area for male black and surf scoters, although some males molted along the coast of Labrador-Newfoundland. Black scoters instrumented on the Restigouche River, which is a major staging area, were widely distributed along the Atlantic Coast from Cape Cod to Georgia during winter. Major wintering areas for black scoters were Cape Cod (Martha's Vineyard and Nantucket Island), Long Island, and New Jersey. In these northern marine wintering areas, black scoters were located farther from shore (4.2 km) and in deeper water (8.3 m) than black scoters in more southern estuarine areas, where distance from shore was 3.1 km and water depth was 5.2 m. Surf scoters instrumented in Chesapeake Bay in late winter showed a strong tendency to return to the Bay the following winter after they had migrated to and from breeding areas. In Chesapeake Bay, black scoters and surf scoters were located mostly in mesohaline areas that had similar water depths (5.1 m vs. 7.5 m) and distances from shore (3.0 km vs. 2.9 km). Distance from shore and depth of water increased over time during the winter for both species. Updated information from the ARGOS Systems aboard the NOAA satellites on scoter movements was made accessible on

  15. The relationships among Black consciousness, self-esteem, and academic self-efficacy in African American men.

    Science.gov (United States)

    Okech, Allan Prince; Harrington, Rick

    2002-03-01

    The purpose of this study was to investigate the relationships among Black consciousness, self-esteem, and academic self-efficacy in African American men. The participants were 120 African American male college students at a predominantly African American university. The authors administered 3 instruments--the Developmental Inventory of Black Consciousness (DIB-C; J. Milliones, 1980), the M. Rosenberg (1965) Self-Esteem Scale, and R. E. Wood and E. A. Locke's (1987) Academic Self-Efficacy Scale--to test the hypotheses. They used an independent-measures t test and a Pearson r correlation to analyze the data. The results of the study supported the hypotheses under investigation. Significant positive relationships were found between Black consciousness and self-esteem and Black consciousness and academic self-efficacy. The results of the study showed that Black consciousness appears to be an important construct to use in understanding self-esteem and academic self-efficacy in African American men.

  16. Black Hole Sign Predicts Poor Outcome in Patients with Intracerebral Hemorrhage.

    Science.gov (United States)

    Li, Qi; Yang, Wen-Song; Chen, Sheng-Li; Lv, Fu-Rong; Lv, Fa-Jin; Hu, Xi; Zhu, Dan; Cao, Du; Wang, Xing-Chen; Li, Rui; Yuan, Liang; Qin, Xin-Yue; Xie, Peng

    2018-01-01

    In spontaneous intracerebral hemorrhage (ICH), black hole sign has been proposed as a promising imaging marker that predicts hematoma expansion in patients with ICH. The aim of our study was to investigate whether admission CT black hole sign predicts hematoma growth in patients with ICH. From July 2011 till February 2016, patients with spontaneous ICH who underwent baseline CT scan within 6 h of symptoms onset and follow-up CT scan were recruited into the study. The presence of black hole sign on admission non-enhanced CT was independently assessed by 2 readers. The functional outcome was assessed using the modified Rankin Scale (mRS) at 90 days. Univariate and multivariable logistic regression analyses were performed to assess the association between the presence of the black hole sign and functional outcome. A total of 225 patients (67.6% male, mean age 60.3 years) were included in our study. Black hole sign was identified in 32 of 225 (14.2%) patients on admission CT scan. The multivariate logistic regression analysis demonstrated that age, intraventricular hemorrhage, baseline ICH volume, admission Glasgow Coma Scale score, and presence of black hole sign on baseline CT independently predict poor functional outcome at 90 days. There are significantly more patients with a poor functional outcome (defined as mRS ≥4) among patients with black hole sign than those without (84.4 vs. 32.1%, p black hole sign independently predicts poor outcome in patients with ICH. Early identification of black hole sign is useful in prognostic stratification and may serve as a potential therapeutic target for anti-expansion clinical trials. © 2018 S. Karger AG, Basel.

  17. African American Male Faculty Satisfaction: Does Institutional Type Make a Difference?

    Directory of Open Access Journals (Sweden)

    Kendricks Hooker

    2011-08-01

    Full Text Available This qualitative study explored the job satisfaction of 16 tenure-line, African American male faculty at a historically Black university and a predominantly White institution. The common themes found in this study were autonomy and flexibility, location, institutional fit, and salary. In addition, there were some themes that were unique to institutional type such as the opportunity to give back to students and student diversity. Findings provide insight for institutional leaders to understand what influences the satisfaction of African American male faculty in different institutional contexts.

  18. Racial Identity and the MMPI in African American Male College Students.

    Science.gov (United States)

    Whatley, P. Richard; Allen, James; Dana, Richard H.

    2003-01-01

    Examines the relation of the Minnesota Multiphasic Personality Inventory (MMPI) to the Racial Identity Attitude Scale-Black, Short Form (RIAS-B) was examined among 50 African American male college students Results indicated RIAS-B scale scores functioned as predictors of MMPI scale scores. Implications of these findings for MMPI-2 research with…

  19. The Black of Strei – a Swine Population on the Verge of Extinction in Banat

    Directory of Open Access Journals (Sweden)

    Marcel Matiuti

    2011-05-01

    Full Text Available The Black of Strei swine was declared to be extinct in 1974, but research conducted in 2008-2010 proved that there are still 61 specimens (Black of Strei proper and hybrids in the Hatzeg county and in the Lugoj area. Body measurements have been made in the case of those specimens and they showed that the specimens are a morphoproductive type. The local people appreciate the Black of Strei especially for its fat and bard which are very dry and used in order to obtain the traditional food products in the area. Prolificacy of sows farrowing is an 8 piglets per gestation. This breed is best kept in organic farms. The Black of Strei females are usually cross-bred with wildboar (Sus scrofa ferus males, the hybrids’ meat being very appreciated.

  20. Interfering Effect of Black Tea Consumption on Diagnosis of Pancreatic Cancer by CA 19-9.

    Science.gov (United States)

    Al-Janabi, Ali Abdul Hussein S; Tawfeeq, Ekhlas F

    2017-06-01

    The study aims to determine the possible effects of black tea consumption on the level of CA 19-9 antigen in the human body. The level of CA 19-9 was measured in 270 healthy individuals who consumed heavy amounts of black tea. About 43.3 % of involved individuals were revealed to have elevated levels of CA 19-9. Males with high values of CA 19-9 represented the greatest number of involved individuals. The cutoff value of high levels of CA 19-9 in all individuals was ranged 69-105 U/ml. Consuming heavy amounts of black tea could be considered an important interfering factor that affects the levels of CA 19-9. The cutoff or predictive value of CA 19-9 in heavy-consuming people of black tea was determined.

  1. Contrasting activity patterns of sympatric and allopatric black and grizzly bears

    Science.gov (United States)

    Schwartz, C.C.; Cain, S.L.; Podruzny, S.; Cherry, S.; Frattaroli, L.

    2010-01-01

    The distribution of grizzly (Ursus arctos) and American black bears (U. americanus) overlaps in western North America. Few studies have detailed activity patterns where the species are sympatric and no studies contrasted patterns where populations are both sympatric and allopatric. We contrasted activity patterns for sympatric black and grizzly bears and for black bears allopatric to grizzly bears, how human influences altered patterns, and rates of grizzlyblack bear predation. Activity patterns differed between black bear populations, with those sympatric to grizzly bears more day-active. Activity patterns of black bears allopatric with grizzly bears were similar to those of female grizzly bears; both were crepuscular and day-active. Male grizzly bears were crepuscular and night-active. Both species were more night-active and less day-active when ???1 km from roads or developments. In our sympatric study area, 2 of 4 black bear mortalities were due to grizzly bear predation. Our results suggested patterns of activity that allowed for intra- and inter-species avoidance. National park management often results in convergence of locally high human densities in quality bear habitat. Our data provide additional understanding into how bears alter their activity patterns in response to other bears and humans and should help park managers minimize undesirable bearhuman encounters when considering needs for temporal and spatial management of humans and human developments in bear habitats. ?? 2010 The Wildlife Society.

  2. Black Alcoholism.

    Science.gov (United States)

    Watts, Thomas D.; Wright, Roosevelt

    1988-01-01

    Examines some aspects of the problem of alcoholism among Blacks, asserting that Black alcoholism can best be considered in an ecological, environmental, sociocultural, and public health context. Notes need for further research on alcoholism among Blacks and for action to reduce the problem of Black alcoholism. (NB)

  3. Beyond Black and White: How White, Male, College Students See Their Asian American Peers

    Science.gov (United States)

    Cabrera, Nolan L.

    2014-01-01

    This research is a cross-site analysis of how white, male, college students see their Asian American peers. Semi-structured interviews with 43 white males were conducted at two universities that differed substantially in their representation of Asian American students. The interviews were theoretically framed by Critical Whiteness Studies and Bobo…

  4. Trends with corticosteroid use in males with Duchenne muscular dystrophy born 1982-2001.

    Science.gov (United States)

    Fox, Deborah J; Kumar, Anil; West, Nancy A; DiRienzo, A Gregory; James, Katherine A; Oleszek, Joyce

    2015-01-01

    This study examines trends in corticosteroid use for males with Duchenne muscular dystrophy by birth year, race/ethnicity, and knowledge of Duchenne muscular dystrophy family history. Firstborn males (n = 521) selected from a population-based surveillance system of Duchenne muscular dystrophy were analyzed using Kaplan Meier and regression methods. Comparing males born 1982 to 1986 with males born 1997 to 2001, steroid use increased from 54% to 72% and mean age at steroid initiation decreased from 8.2 to 7.1 years. Hispanics and non-Hispanic Black males used steroids less frequently and delayed initiation compared to white males. Compared to males without a Duchenne muscular dystrophy family history, males with known family history were half as likely to use steroids. Duration of steroid use increased over time and age at initiation decreased. Racial/ethnic disparities exist for steroid use and should be addressed to improve outcome and quality of life for boys with Duchenne muscular dystrophy. © The Author(s) 2014.

  5. Effect of Black maca (Lepidium meyenii) on one spermatogenic cycle in rats.

    Science.gov (United States)

    Gonzales, G F; Nieto, J; Rubio, J; Gasco, M

    2006-10-01

    Lepidium meyenii (Maca) grows exclusively between 4000 and 4500 m above sea level in the Peruvian central Andes. The hypocotyls of this plant are traditionally used in the Andean region for their supposed fertility-enhancing properties. The hypocotyls have different colours. Of these, Black maca has better effects on spermatogenesis. The present study aimed to test the hypothesis that Black maca has early effects during a spermatogenic cycle (12 days) of male rats. For this, testicular spermatid, epididymal sperm and vas deferens sperm counts were measured after 1, 3, 5, 7 and 12 days of treatment with Black maca. Aqueous extract of Black maca was given orally by daily gavage at a dose of 2 g kg(-1). In a spermatogenic cycle, compared with day 1, daily sperm production (DSP) was lower at day 7 (control), whereas with Black maca, the difference was observed at day 12. Epididymal sperm count was higher in rats treated with Black maca at days 1, 3 and 7, but similar to controls at days 5 and 12; similarly sperm counts in vas deferens was higher in rats treated with Black maca in days 3, 5 and 7, but similar to controls at days 1 and 12. From this, it is suggested that first action of Black maca was at epididymal level increasing sperm count after 1 day of treatment, whereas an increase in sperm count was observed in vas deferens at day 3 of treatment. Finally, an increase in DSP was observed after 7 days of treatment with Black maca. Testicular testosterone was not affected after 7 days treatment with Black maca. In conclusion, Black maca affects sperm count as early as 1 day after beginning of treatment.

  6. Black holes

    OpenAIRE

    Brügmann, B.; Ghez, A. M.; Greiner, J.

    2001-01-01

    Recent progress in black hole research is illustrated by three examples. We discuss the observational challenges that were met to show that a supermassive black hole exists at the center of our galaxy. Stellar-size black holes have been studied in x-ray binaries and microquasars. Finally, numerical simulations have become possible for the merger of black hole binaries.

  7. The phase structure of higher-dimensional black rings and black holes

    International Nuclear Information System (INIS)

    Emparan, Roberto; Harmark, Troels; Niarchos, Vasilis; Obers, Niels A.; RodrIguez, Maria J.

    2007-01-01

    We construct an approximate solution for an asymptotically flat, neutral, thin rotating black ring in any dimension D ≥ 5 by matching the near-horizon solution for a bent boosted black string, to a linearized gravity solution away from the horizon. The rotating black ring solution has a regular horizon of topology S 1 x S D-3 and incorporates the balancing condition of the ring as a zero-tension condition. For D = 5 our method reproduces the thin ring limit of the exact black ring solution. For D ≥ 6 we show that the black ring has a higher entropy than the Myers-Perry black hole in the ultra-spinning regime. By exploiting the correspondence between ultra-spinning black holes and black membranes on a two-torus, we take steps towards qualitatively completing the phase diagram of rotating blackfolds with a single angular momentum. We are led to propose a connection between MP black holes and black rings, and between MP black holes and black Saturns, through merger transitions involving two kinds of 'pinched' black holes. More generally, the analogy suggests an infinite number of pinched black holes of spherical topology leading to a complicated pattern of connections and mergers between phases

  8. On the Charter Question: Black Marxism and Black Nationalism

    Science.gov (United States)

    Stern, Mark; Hussain, Khuram

    2015-01-01

    This article brings two black intellectual traditions to bear on the question of charter schools: black Marxism and black nationalism. The authors examine the theoretical and rhetorical devices used to talk about charters schools by focusing on how notions of "black liberation" are deployed by the charter movement, and to what end. The…

  9. "Be Real Black for Me": Imagining BlackCrit in Education

    Science.gov (United States)

    Dumas, Michael J.; ross, kihana miraya

    2016-01-01

    The authors put forward a theorization of a Black Critical Theory, or what might be called BlackCrit, within, and in response to, Critical Race Theory, and then outline ways that BlackCrit in education helps us to more incisively analyze how the specificity of (anti)blackness matters in explaining how Black bodies become marginalized, disregarded,…

  10. Black hole astrophysics

    International Nuclear Information System (INIS)

    Blandford, R.D.; Thorne, K.S.

    1979-01-01

    Following an introductory section, the subject is discussed under the headings: on the character of research in black hole astrophysics; isolated holes produced by collapse of normal stars; black holes in binary systems; black holes in globular clusters; black holes in quasars and active galactic nuclei; primordial black holes; concluding remarks on the present state of research in black hole astrophysics. (U.K.)

  11. What explains the different rates of human papillomavirus vaccination among adolescent males and females in the United States?

    Directory of Open Access Journals (Sweden)

    Yoonyoung Choi

    2016-12-01

    Full Text Available Purpose: To identify factors that explain differences in HPV vaccination rates for male and female adolescents and to determine self-reported barriers by parents affecting vaccination decisions. Methods: The sample included adolescents 13–17 years old with a vaccination record documented in the 2012 and 2013 National Immunization Survey-Teen dataset. A logistic regression model was developed with 13 socio-demographic factors and survey year, along with significant interaction pairs with gender. Results: Subjects included 20,355 and 18,350 adolescent boys and girls, respectively. About half of the females (56% received at least one dose of HPV vaccine, compared to 28% of males. Several factors differed between males and females, including higher vaccination rates among non-Hispanic Black males and lower vaccination rates for non-Hispanic Black females compared to Whites; and a stronger association with health care provider recommendation among males. The most common parental reasons for not vaccinating their children included ‘not recommended by a health care provider’ for males (24%, and ‘unnecessary’ for females (18%. Conclusion: We found a significant gender interaction with several socio-demographic variables in predicting vaccination uptake. These gender differences may be partially an artifact of timing, because male vaccination became routine approximately five years after female vaccination. Keywords: Human papillomavirus, Adolescent health, Vaccination, NIS-Teen, Gender interaction

  12. Dominant lethal mutations research in mice fed with irradiated black beams

    International Nuclear Information System (INIS)

    Andrade, Z.P.

    1982-01-01

    To evaluate the potential mutagenic effects of irradiated black beans (Phaseolus vulgaris) with conservation purpose, in germ cells of mice, dominant lethal assay were employed. Three groups of albino swiss male mice (S W-55) were fed with a normal ration, or unirradiated or irradiated (0,2; 0,5; 1; 5; 10; 15 e 20 KGy) test diets for eight weeks. After the feeding period the males were mated with groups of untreated females mice for four consecutive weeks. Numbers of pregnancy rates females were observed. The females were autopsied at mid-term pregnancy for evaluation of dominant lethal mutations. (author)

  13. Blood biochemical parameters in male American mink (Neovison vison before and during the breeding season

    Directory of Open Access Journals (Sweden)

    Bogdan Lasota

    2014-05-01

    Full Text Available This study was aimed at selected blood biochemical parameters in the male American mink before (September-November and during the breeding (January-March season. Blood from 143 Black and Sapphire male mink at one year age was collected. The plasma was assayed for the concentration of glucose, total protein, cholesterol, HDL and LDL fractions, triacylglycerides (TG, and the activity of ALT and AST. Concentrations of glucose, protein, total and HDL/LDL cholesterol, and AST activity were generally slightly higher during the breeding season than during the non-breeding season, but remained within the reference range. In the case of ALT activity and TG concentration, the relations were reversed. The parameters studied in the Sapphire mink showed greater variation, both in- and out of the season. In Black and Sapphire males of the American mink, the studied parameters revealed slightly higher values during the breeding season than the non-breeding season. This will vary depending on the color variety. The decrease in TG concentration during the breeding season may indicate an increased energy demand due to ambient temperature falls, and/or may be a sign of increased energy consumption associated with physical exertion during mating. Consideration should be given to the nutrition of male mink during the breeding season.

  14. "I am Not a Statistic": Identities of African American Males in Advanced Science Courses

    Science.gov (United States)

    Johnson, Diane Wynn

    African American males' interest, motivation, and enjoyment for science. They also focused on the personal importance they placed on doing well on a task (attainment value), or how useful the students believe the course relates to their current or future goals (utility value). Students who strongly or moderately identified with science were more likely to stress the value of the advanced science course(s), in terms of enjoyment, utility for their futures, and personal importance, and to downplay the work involved. Students who had low or no identification with science were more likely to stress the social enjoyment of the course they were enrolled in, relating to the other students, the fun activities, the teacher, and more likely to address the difficulty of the course. However, all of the students stressed the value of the course for their future as college students. Regardless of the level of identification with science, students were effusive in their respect for and praise of their science teacher(s) and the role he and/or she played in their interest in the subject matter, providing interesting and engaging work in class. The teacher as a role model, especially the Black male teacher, was critical to the learning of science for these students. Parents of all of these African American males conveyed the importance of academic achievement, and participated in school events as well as monitored their students' activities outside of school. All of the parents of the students in this study were supportive of their sons and had high expectations for academic success, regardless of whether they had attended college or completed a degree. In contrast to the literature on African American males, these students had a sense of academic excellence, high self-esteem, and their families and science teachers had high academic expectations for them. This study addresses a group often missing from the literature: successful African American male high school students. The study

  15. Contemporary Black Theatre.

    Science.gov (United States)

    Thomas, Pearl

    The distinguishable black theatre in America, mirroring a distinguishable black experience, is an artistic product which demands audience involvement. Both the Afro-American oral tradition and the art of gesture are integral aspects of black theatre. In addition, the tragedy found black theatre is not tragedy in the classic sense, as blacks feel…

  16. The trials, tribulations, and triumphs of black faculty in the math and science pipeline: A life history approach

    Science.gov (United States)

    Williams, Lisa D.

    2000-12-01

    This study explores the career progression and life history of black mathematicians and scientists who teach on university faculties in the United States. It investigates the following questions: Why are there so few black mathematicians and scientists in colleges and universities in the United States? What is the experience of black students who express an interest in science and math? What barriers do black scientists and mathematicians face as they move through school towards their career in higher education? What factors facilitate their success? The current literature shows that there are few women and minorities teaching or working in math and science compared to white men, although reasons for this underrepresentation are still not well understood. I explored this phenomenon by conducting two sets of in-depth interviews with twelve black faculty, six women, six men, from both historically black and predominantly white higher educational institutions in the United States. My interviews were based upon a life history approach that identified the participants' perceptions of the barriers and obstacles, as well as the supports and facilitators encountered in their schooling and career progression. The findings from the study show the importance of a strong family, community, and teacher support for the participants throughout their schooling. Support systems continued to be important in their faculty positions. These support systems include extended family members, teachers, community members, supervisors, and classmates, who serve as role models and mentors. The life study interviews provide striking evidence of the discrimination, isolation, and harassment due to race and gender experienced by black male and female mathematicians and scientists. The racial discrimination and the compounding effect of racism and sexism play out differently for the male and female participants in this study. This study suggests directions for future research on the experiences

  17. Caged black holes: Black holes in compactified spacetimes. I. Theory

    International Nuclear Information System (INIS)

    Kol, Barak; Sorkin, Evgeny; Piran, Tsvi

    2004-01-01

    In backgrounds with compact dimensions there may exist several phases of black objects including a black hole and a black string. The phase transition between them raises questions and touches on fundamental issues such as topology change, uniqueness, and cosmic censorship. No analytic solution is known for the black hole, and moreover one can expect approximate solutions only for very small black holes, while phase transition physics happens when the black hole is large. Hence we turn to numerical solutions. Here some theoretical background to the numerical analysis is given, while the results will appear in a subsequent paper. The goals for a numerical analysis are set. The scalar charge and tension along the compact dimension are defined and used as improved order parameters which put both the black hole and the black string at finite values on the phase diagram. The predictions for small black holes are presented. The differential and the integrated forms of the first law are derived, and the latter (Smarr's formula) can be used to estimate the 'overall numerical error'. Field asymptotics and expressions for physical quantities in terms of the numerical values are supplied. The techniques include the 'method of equivalent charges', free energy, dimensional reduction, and analytic perturbation for small black holes

  18. Primary black holes

    International Nuclear Information System (INIS)

    Novikov, I.; Polnarev, A.

    1981-01-01

    Proves are searched for of the formation of the so-called primary black holes at the very origin of the universe. The black holes would weigh less than 10 13 kg. The formation of a primary black hole is conditional on strong fluctuations of the gravitational field corresponding roughly to a half of the fluctuation maximally permissible by the general relativity theory. Only big fluctuations of the gravitational field can overcome the forces of the hot gas pressure and compress the originally expanding matter into a black hole. Low-mass black holes have a temperature exceeding that of the black holes formed from stars. A quantum process of particle formation, the so-called evaporation takes place in the strong gravitational field of a black hole. The lower the mass of the black hole, the shorter the evaporation time. The analyses of processes taking place during the evaporation of low-mass primary black holes show that only a very small proportion of the total mass of the matter in the universe could turn into primary black holes. (M.D.)

  19. Black Male College Achievers and Resistant Responses to Racist Stereotypes at Predominantly White Colleges and Universities

    Science.gov (United States)

    Harper, Shaun R.

    2015-01-01

    In this article, Shaun R. Harper investigates how Black undergraduate men respond to and resist the internalization of racist stereotypes at predominantly White colleges and universities. Prior studies consistently show that racial stereotypes are commonplace on many campuses, that their effects are usually psychologically and academically…

  20. 77 FR 70423 - Black Bear Hydro Partners, LLC and Black Bear Development Holdings, LLC and Black Bear SO, LLC...

    Science.gov (United States)

    2012-11-26

    ... Bear Hydro Partners, LLC and Black Bear Development Holdings, LLC and Black Bear SO, LLC; Notice of..., 2012, Black Bear Hydro Partners, LLC, sole licensee (transferor) and Black Bear Development Holdings, LLC and Black Bear SO, LLC (transferees) filed an application for the partial the transfer of licenses...

  1. Phase transition for black holes with scalar hair and topological black holes

    International Nuclear Information System (INIS)

    Myung, Yun Soo

    2008-01-01

    We study phase transitions between black holes with scalar hair and topological black holes in asymptotically anti-de Sitter spacetimes. As the ground state solutions, we introduce the non-rotating BTZ black hole in three dimensions and topological black hole with hyperbolic horizon in four dimensions. For the temperature matching only, we show that the phase transition between black hole with scalar hair (Martinez-Troncoso-Zanelli black hole) and topological black hole is second-order by using differences between two free energies. However, we do not identify what order of the phase transition between scalar and non-rotating BTZ black holes occurs in three dimensions, although there exists a possible decay of scalar black hole to non-rotating BTZ black hole

  2. From binary black hole simulation to triple black hole simulation

    International Nuclear Information System (INIS)

    Bai Shan; Cao Zhoujian; Han, Wen-Biao; Lin, Chun-Yu; Yo, Hwei-Jang; Yu, Jui-Ping

    2011-01-01

    Black hole systems are among the most promising sources for a gravitational wave detection project. Now, China is planning to construct a space-based laser interferometric detector as a follow-on mission of LISA in the near future. Aiming to provide some theoretical support to this detection project on the numerical relativity side, we focus on black hole systems simulation in this work. Considering the globular galaxy, multiple black hole systems also likely to exist in our universe and play a role as a source for the gravitational wave detector we are considering. We will give a progress report in this paper on our black hole system simulation. More specifically, we will present triple black hole simulation together with binary black hole simulation. On triple black hole simulations, one novel perturbational method is proposed.

  3. Surface geometry of 5D black holes and black rings

    International Nuclear Information System (INIS)

    Frolov, Valeri P.; Goswami, Rituparno

    2007-01-01

    We discuss geometrical properties of the horizon surface of five-dimensional rotating black holes and black rings. Geometrical invariants characterizing these 3D geometries are calculated. We obtain a global embedding of the 5D rotating black horizon surface into a flat space. We also describe the Kaluza-Klein reduction of the black ring solution (along the direction of its rotation) which, though it is nakedly singular, relates this solution to the 4D metric of a static black hole distorted by the presence of external scalar (dilaton) and vector ('electromagnetic') fields. The properties of the reduced black hole horizon and its embedding in E 3 are briefly discussed

  4. Discrimination Increases Suicidal Ideation in Black Adolescents Regardless of Ethnicity and Gender

    Directory of Open Access Journals (Sweden)

    Shervin Assari

    2017-11-01

    Full Text Available Background: Discrimination is a common experience for Blacks across various developmental periods. Although much is known about the effect of discrimination on suicidal ideation of adults, less is known about the same association in Black youth. Aim: We examined the association between discrimination and suicidal ideation in a national sample of Black youth. We also explored gender and ethnic differences in this association. Methods: We used data from the National Survey of American Life-Adolescents (NSAL-A, 2003–2004. In total, 1170 Black adolescents entered the study. This number was composed of 810 African American and 360 Caribbean Black youth (aged 13 to 17 years. Demographic and socioeconomic factors were controls, perceived discrimination was the predictor, and lifetime suicidal ideation was the outcome. Logistic regression was used to test the association between perceived discrimination and suicidal ideation in the pooled sample, as well as based on ethnicity and gender. Results: In the pooled sample of Black youth, higher perceived discrimination was associated with higher odds of suicidal ideation (Odds Ratio (OR = 1.09; 95% Confidence Interval (CI = 1.02−1.17. This association was significant net of age, ethnicity, gender, and socioeconomic status. We did not find interactions between perceived discrimination and ethnicity or gender on suicidal ideation. Perceived discrimination was associated with suicidal ideation in African Americans (CI = 1.09; 95% CI = 1.01−1.17 and Caribbean Blacks (CI = 1.16; 95% CI = 1.03−1.32, males (CI = 1.11; 95% CI = 1.00−1.25, and females (CI = 1.08; 95% CI = 1.00−1.16. Conclusion: Discrimination jeopardizes the mental health of Black youth. In a universal pattern, discrimination is associated with suicidal ideation in Black youth. More research is needed on this topic.

  5. Discrimination Increases Suicidal Ideation in Black Adolescents Regardless of Ethnicity and Gender.

    Science.gov (United States)

    Assari, Shervin; Moghani Lankarani, Maryam; Caldwell, Cleopatra Howard

    2017-11-06

    Discrimination is a common experience for Blacks across various developmental periods. Although much is known about the effect of discrimination on suicidal ideation of adults, less is known about the same association in Black youth. We examined the association between discrimination and suicidal ideation in a national sample of Black youth. We also explored gender and ethnic differences in this association. We used data from the National Survey of American Life-Adolescents (NSAL-A), 2003-2004. In total, 1170 Black adolescents entered the study. This number was composed of 810 African American and 360 Caribbean Black youth (aged 13 to 17 years). Demographic and socioeconomic factors were controls, perceived discrimination was the predictor, and lifetime suicidal ideation was the outcome. Logistic regression was used to test the association between perceived discrimination and suicidal ideation in the pooled sample, as well as based on ethnicity and gender. In the pooled sample of Black youth, higher perceived discrimination was associated with higher odds of suicidal ideation (Odds Ratio (OR) = 1.09; 95% Confidence Interval (CI) = 1.02-1.17). This association was significant net of age, ethnicity, gender, and socioeconomic status. We did not find interactions between perceived discrimination and ethnicity or gender on suicidal ideation. Perceived discrimination was associated with suicidal ideation in African Americans (CI = 1.09; 95% CI = 1.01-1.17) and Caribbean Blacks (CI = 1.16; 95% CI = 1.03-1.32), males (CI = 1.11; 95% CI = 1.00-1.25), and females (CI = 1.08; 95% CI = 1.00-1.16). Discrimination jeopardizes the mental health of Black youth. In a universal pattern, discrimination is associated with suicidal ideation in Black youth. More research is needed on this topic.

  6. Black Holes

    OpenAIRE

    Townsend, P. K.

    1997-01-01

    This paper is concerned with several not-quantum aspects of black holes, with emphasis on theoretical and mathematical issues related to numerical modeling of black hole space-times. Part of the material has a review character, but some new results or proposals are also presented. We review the experimental evidence for existence of black holes. We propose a definition of black hole region for any theory governed by a symmetric hyperbolic system of equations. Our definition reproduces the usu...

  7. The Overrepresentation of African-American Males in Special Education and the Effects on Self Esteem Based on Teachers' Perceptions

    Science.gov (United States)

    Parker, DeJuan Dennis

    2013-01-01

    In this twenty-first century there is a disproportionate amount of African American males in special education in the U.S. This is a factor happening day by day affecting the achievement gap between Black and White students, especially males. The purpose of this study is to point out factors that contribute to the overrepresentation of African…

  8. Black silicon solar cells with black bus-bar strings

    DEFF Research Database (Denmark)

    Davidsen, Rasmus Schmidt; Tang, Peter Torben; Mizushima, Io

    2016-01-01

    We present the combination of black silicon texturing and blackened bus-bar strings as a potential method for obtaining all-black solar panels, while using conventional, front-contacted solar cells. Black silicon was realized by maskless reactive ion etching resulting in total, average reflectance...... below 0.5% across a 156x156 mm2 silicon wafer. Four different methods to obtain blackened bus-bar strings were compared with respect to reflectance, and two of these methods (i.e., oxidized copper and etched solder) were used to fabricate functional allblack solar 9-cell panels. The black bus-bars (e.......g., by oxidized copper) have a reflectance below 3% in the entire visible wavelength range. The combination of black silicon cells and blackened bus-bars results in aesthetic, all-black panels based on conventional, front-contacted solar cells without compromising efficiency....

  9. Sex ratio at birth and racial differences: Why do Black women give ...

    African Journals Online (AJOL)

    The two important questions that this paper will attempt to answer are: (1) why is it that regardless of race/ethnicity or geographic location, the sex ratio data at birth show more males than females?; and (2) Why is it that regardless of geographic location compared to other racial/ethnic groups, Black women or Women of ...

  10. Effect of contact with male on the physical and chemical qualities of ...

    African Journals Online (AJOL)

    A group of 30 Black HARCO laying hens were reared together with 3 mature cocks, while another group were reared in an adjacent pen without cocks. Thus, while the first group of hens had full physical contact (including mating) with the males, the second group was restricted only to auditory and visual contacts with the ...

  11. Racializing Experiences of Foreign-Born and Ethnically Diverse Black Male Engineering Graduate Students: Implications for Student Affairs Practice, Policy, and Research

    Science.gov (United States)

    Burt, Brian A.; Knight, Alexander; Robeson, Justin

    2017-01-01

    Despite a growing body of work on the experiences of Black collegians, the higher education knowledge base lacks scholarship focused on Black men in graduate programs who are foreign-born and/or identify ethnically as other than African American. In this article, we provide a domain-specific investigation (i.e., based on students' field of study),…

  12. Distortion of Schwarzschild-anti-de Sitter black holes to black strings

    International Nuclear Information System (INIS)

    Tomimatsu, Akira

    2005-01-01

    Motivated by the existence of black holes with various topologies in four-dimensional spacetimes with a negative cosmological constant, we study axisymmetric static solutions describing any large distortions of Schwarzschild-anti-de Sitter black holes parametrized by the mass m. Under the approximation such that m is much larger than the anti-de Sitter radius, it is found that a cylindrically symmetric black string is obtained as a special limit of distorted spherical black holes. Such a prolonged distortion of the event horizon connecting a Schwarzschild-anti-de Sitter black hole to a black string is allowed without violating both the usual black hole thermodynamics and the hoop conjecture for the horizon circumference

  13. Saving Black and Latino Boys: What Schools Can Do to Make a Difference

    Science.gov (United States)

    Noguera, Pedro A.

    2012-01-01

    More educators are embracing the idea that the educational and social challenges confronting black and Latino males can be solved, or at least ameliorated, through single-sex education; such schools specifically designed for young men of color, are now proliferating across the nation. Nonetheless, there is a pressing need for an applied research…

  14. Scream-embrace displays in wild black-horned capuchin monkeys.

    Science.gov (United States)

    Lynch Alfaro, Jessica

    2008-06-01

    Reintroduction of capuchin monkeys (Cebus apella) into their social group in captivity can elicit sirena screams and embraces. Captive scream-embrace displays are male biased, and females never perform sirena screams. One hypothesis is that scream-embrace displays serve a tension-reduction or reconciliatory function between males with conflicting interests. Alternatively, these displays may function to maintain strong affiliative bonds between friendly male dyads. Scream and/or embrace displays in wild Brazilian black-horned capuchins were analyzed for social and ecological contexts, behavioral components, and individuals involved. Seventy-two displays were observed during the 199-day study period. Among the 66 displays for which both members could be identified by sex, there were 42 occurrences of male-male dyads, 17 of male-female dyads, and seven of female-female dyads. Scream-embrace dyads were male-male pairs significantly more often than expected from group membership, and the alpha male was the only male to engage in scream-embrace displays with females. Female-female pairs did embrace, but never emitted sirena screams. Displays most commonly occurred in "reunion" contexts, primarily the reuniting of subgroups after hours or days out of contact, but also after intergroup encounters, and across groups in "intergroup" displays. Displays were rare, but socially contagious, and subgroup reunions could elicit multiple displays in rapid succession. Although the occurrence of screams and embraces was positively correlated, both behaviors also occurred independently, and their functions may be different. Male sirena screams may be honest advertisements of united alliances, directed toward a third party, whereas the embrace may be a risky affiliative signal, directed primarily within the dyad. Copyright 2008 Wiley-Liss, Inc.

  15. Low-mass black holes as the remnants of primordial black hole formation.

    Science.gov (United States)

    Greene, Jenny E

    2012-01-01

    Bridging the gap between the approximately ten solar mass 'stellar mass' black holes and the 'supermassive' black holes of millions to billions of solar masses are the elusive 'intermediate-mass' black holes. Their discovery is key to understanding whether supermassive black holes can grow from stellar-mass black holes or whether a more exotic process accelerated their growth soon after the Big Bang. Currently, tentative evidence suggests that the progenitors of supermassive black holes were formed as ∼10(4)-10(5) M(⊙) black holes via the direct collapse of gas. Ongoing searches for intermediate-mass black holes at galaxy centres will help shed light on this formation mechanism.

  16. Seroprevalence of Toxoplasma gondii and Trichinella spiralis in North Carolina black bears (Ursus americanus).

    Science.gov (United States)

    Nutter, F B; Levine, J F; Stoskopf, M K; Gamble, H R; Dubey, J P

    1998-10-01

    Serum samples from 143 hunter-killed black bears were collected during the 1996 and 1997 black bear hunting seasons in eastern North Carolina. All samples were tested for antibodies to Toxoplasma gondii by the modified agglutination test. Antibodies to T. gondii were present in 120 of 143 (84%) bears. Females had significantly higher titers than males (Wilcoxon rank sums test, P = 0.045), and titers increased with age (Jonckheere test, P = 0.01). Samples collected during 1996 (n = 79) were tested for antibodies to Trichinella spiralis by enzyme-linked immunosorbent assay. No samples were positive for antibodies to T. spiralis.

  17. Motivations of female Black Hills deer hunters

    Science.gov (United States)

    Gigliotti, Larry M.; Covelli Metcalf, Elizabeth

    2016-01-01

    State fish and wildlife agencies are particularly interested in attracting female participation because of the potential to offset declining participation in hunting. Understanding female hunters’ motivations will be critical for designing effective recruitment and retention programs for women hunters. Although female participation in hunting is increasing, males still outnumber females by about tenfold. Gender differences in deer hunters were explored by comparing ratings of eight motivations (social, nature, excitement, meat, challenge, trophy, extra hunting opportunity, and solitude). Hunter types were defined by hunters’ selection of the most important motivation for why they like Black Hills deer hunting. Overall, females and males were relatively similar in their ratings of the eight motivations, and we found 85% gender similarity in the selection of the most important motivation. Women were slightly more motivated by the food aspect of the hunt while men placed slightly more value on the hunt as a sporting activity.

  18. Fluctuations in daily energy intake do not cause physiological stress in a Neotropical primate living in a seasonal forest.

    Science.gov (United States)

    Martínez-Mota, Rodolfo; Righini, Nicoletta; Palme, Rupert

    2016-12-01

    Animals may face periods of nutritional stress due to short-term food shortage and/or low energy consumption associated with seasonal fluctuations in resource availability. We tested the hypothesis that periods of restricted macronutrient and energy intake result in energy deficits and physiological stress in wild black howler monkeys (Alouatta pigra) inhabiting seasonal tropical semi-deciduous forests. We conducted full-day follows of focal animals recording feeding rates, time spent feeding, and total amount of food ingested. We carried out nutritional analysis of foods collected from feeding trees and calculated the daily nutrient and energy intake of each focal individual. Fecal glucocorticoid metabolites (fGCM) of focal animals were used as an indicator of physiological stress. We found that fluctuations in daily energy intake across seasons did not have significant effects on fGCM of individuals. However, protein intake was negatively associated with fGCM, highlighting the interplay among macronutrients, metabolism, and the endocrine system. Fecal glucocorticoid metabolites were also positively related to fruit availability, but this relationship was most likely due to social stress associated with intergroup encounters and resource defense that occurred when preferred trees were fruiting. Behavioral strategies such as dietary shifts and nutrient mixing, and metabolic adaptations such as low energy expenditure allowed individuals to fulfill their minimum energy requirements even during periods of decreased resource availability and intake. The present study suggests that seasonal variations in food, macronutrient, and energy acquisition may have limited physiological costs for animals that exploit different types of plant resources such as howler monkeys.

  19. Black Culture

    Directory of Open Access Journals (Sweden)

    Angela Khristin Brown

    2013-07-01

    Full Text Available The migration of blacks in North America through slavery became united.  The population of blacks past downs a tradition of artist through art to native born citizens. The art tradition involved telling stories to each generation in black families. The black culture elevated by tradition created hope to determine their personal freedom to escape from poverty of enslavement and to establish a way of life through tradition. A way of personal freedoms was through getting a good education that lead to a better foundation and a better way of life.

  20. Magnetized black holes and black rings in the higher dimensional dilaton gravity

    International Nuclear Information System (INIS)

    Yazadjiev, Stoytcho S.

    2006-01-01

    In this paper we consider magnetized black holes and black rings in the higher dimensional dilaton gravity. Our study is based on exact solutions generated by applying a Harrison transformation to known asymptotically flat black hole and black ring solutions in higher dimensional spacetimes. The explicit solutions include the magnetized version of the higher dimensional Schwarzschild-Tangherlini black holes, Myers-Perry black holes, and five-dimensional (dipole) black rings. The basic physical quantities of the magnetized objects are calculated. We also discuss some properties of the solutions and their thermodynamics. The ultrarelativistic limits of the magnetized solutions are briefly discussed and an explicit example is given for the D-dimensional magnetized Schwarzschild-Tangherlini black holes

  1. 'The singing hospital'--integrated group therapy in the Black mentally ill.

    Science.gov (United States)

    Benjamin, B

    1983-06-04

    Integrated group therapy was originally introduced at Sterkfontein Hospital in 1957, and reintroduced 6 years ago in an effort to overcome difficulties in communication with approximately 100 Black male and female mental hospital patients. This therapy consisted mainly of song and dance activation, sociodrama, psychodrama and behavioural modification methods. These techniques are flexible, and can be carried out by proxy therapists working with doctors and psychologists.

  2. Agronomic Performance of Flue-Cured Tobacco F1 Hybrids Obtained with Different Sources of Male Sterile Cytoplasm

    Directory of Open Access Journals (Sweden)

    Berbec A

    2014-12-01

    Full Text Available Four cytoplasmic male sterile (cms F1flue-cured hybrids cv. Wiaelica × cv. Virginia Golta (VG, the male fertile analogue and the parental varieties were tested at two locations in Poland in a replicated field trial. The cms sources in the hybrids wereN. suaveolens,N. amplexicaulis,N. bigeloviiand aN. tabacumcms mutant. Under the slight to moderate pressure from black root rot present at the trial sites the hybrids showed a moderate tolerance of the disease characteristic of VG as opposed to medium strong susceptibility of Wislica. Apart from the effect of black root rot tolerance the vegetative vigor of the hybrids (plant height, leaf size, earliness was affected by cytoplasm source. The F1hybrid withN. suaveolens cytoplasm flowered approximately three days later than the remaining hybrids. Of the cms hybrids tested cmsN. bigelovii produced the tallest plants with largest mid-position leaves. Yields of cured leaves were largely influenced by black root rot and were generally higher in VG and in the hybrids than in Wislica. Leaf yields and curability were generally little affected by cms source under low pressure from black root rot. At the site with a relatively high level of black root rot infestation the yields of cmsN. suaveolens were slightly lower but the percentage of light grades slightly higher compared to those of other cms hybrids. CmsN. suaveolens was the best hybrid in terms of money returns at the low black root rot field but it was the poorest hybrid performer under high pressure from the disease. Contents of nitrogen, sugars, nicotine and ash was little affected by source of cms. There was an increased incidence of potato virus Y (PVY and white spots in cmsN. suaveolens and, to a lesser extent, in cmsN. bigelovii as compared to the remaining disease-free entries.

  3. The relationship between gender role conflict and condom use among black MSM.

    Science.gov (United States)

    Malebranche, David J; Gvetadze, Roman; Millett, Gregorio A; Sutton, Madeline Y

    2012-10-01

    Gender role conflict may influence condom use among black MSM. We examined relationships between the Gender Role Conflict Scale (GRCS), social/demographic variables and condom use among 456 black MSM. Higher total GRCS scores did not predict unprotected insertive anal intercourse (UIAI) or unprotected receptive anal intercourse (URAI) with men, but were associated with unprotected vaginal or anal intercourse (UVI/UAI) with women among bisexually active participants (n = 69). Higher perceived HIV risk reduced the likelihood of both UIAI and URAI with men. Internet recruitment venues, sexual discrimination experiences, higher numbers of sex partners and UVI/UAI with women all increased the likelihood of UIAI with men, while education (college/technical school or college degree) was associated with URAI with men. Future sexual health interventions for black MSM should emphasize broader social/demographic and alternative gender role variables with male sexual partners, while traditional GRCS variables may prove useful among those with female sexual partners.

  4. A Comparative Study of Self-Esteem Among Young Black, Spanish, and White Children.

    Science.gov (United States)

    Burger, Mary Louise Hirsh

    This dissertation compared the self-esteem of low socioeconomic black, Spanish, and white males and females in kindergarten, first, and second grades. The subjects used were 416 primary children from two suburban communities adjoining Chicago to whom the Coopersmith Self-Esteem Inventory was given in a revised form. The schools used in the study…

  5. Gender influencers on work values of black adolescents.

    Science.gov (United States)

    Thomas, V G; Shields, L C

    1987-01-01

    Work values and key influencers of a sample of black male and female adolescents were examined. Results indicated that boys and girls valued both the intrinsic and extrinsic rewards of work; however, girls reported slighter stronger extrinsic values than did boys. In addition, the sexes reported differences in the importance of specific work values such as "making lots of money," and "doing important things." When naming a key influencer, respondents tended to cite a same-sex and race individual. Sex of one's key influencer was related to certain work values, with subjects reporting a male key influencer valuing "trying out one's own ideas" and "having a secure future" more than those reporting a female key influencer. The interaction of sex of subject and sex of key influencer was significant on one of the work value outcomes. Implications of these findings are considered.

  6. The Black Lives Matter Movement and Historically Black Colleges and Universities

    Science.gov (United States)

    Gasman, Marybeth

    2017-01-01

    This article looks at the Black Lives Matter Movement and Historically Black Colleges and Universities. Historically Black Colleges and Universities (HBCUs) continue to play an important role in society. However, what the Black Lives Matter movement shows consistently is that predominantly White institutions need to change, to step up and embrace…

  7. Survival advantage in black versus white men with CKD: effect of estimated GFR and case mix.

    Science.gov (United States)

    Kovesdy, Csaba P; Quarles, L Darryl; Lott, Evan H; Lu, Jun Ling; Ma, Jennie Z; Molnar, Miklos Z; Kalantar-Zadeh, Kamyar

    2013-08-01

    Black dialysis patients have significantly lower mortality compared with white patients, in contradistinction to the higher mortality seen in blacks in the general population. It is unclear whether a similar paradox exists in patients with non-dialysis-dependent chronic kidney disease (CKD), and if it does, what its underlying reasons are. Historical cohort. 518,406 white and 52,402 black male US veterans with non-dialysis-dependent CKD stages 3-5. Black race. We examined overall and CKD stage-specific all-cause mortality using parametric survival models. The effect of sociodemographic characteristics, comorbid conditions, and laboratory characteristics on the observed differences was explored in multivariable models. During a median follow-up of 4.7 years, 172,093 patients died (mortality rate, 71.0 [95% CI, 70.6-71.3] per 1,000 patient-years). Black race was associated with significantly lower crude mortality (HR, 0.95; 95% CI, 0.94-0.97; P case-mix and laboratory characteristics occurring during the course of kidney disease. Published by Elsevier Inc. on behalf of the National Kidney Foundation, Inc.

  8. Tooth width predictions in a sample of Black South Africans.

    Science.gov (United States)

    Khan, M I; Seedat, A K; Hlongwa, P

    2007-07-01

    Space analysis during the mixed dentition requires prediction of the mesiodistal widths of the unerupted permanent canines and premolars and prediction tables and equations may be used for this purpose. The Tanaka and Johnston prediction equations, which were derived from a North American White sample, is one example which is widely used. This prediction equation may be inapplicable to other race groups due to racial tooth size variability. Therefore the purpose of this study was to derive prediction equations that would be applicable to Black South African subjects. One hundred and ten pre-treatment study casts of Black South African subjects were analysed from the Department of Orthodontics' records at the University of Limpopo. The sample was equally divided by gender with all subjects having Class I molar relationship and relatively well aligned teeth. The mesiodistal widths of the maxillary and mandibular canines and premolars were measured with a digital vernier calliper and compared with the measurements predicted with the Tanaka and Johnston equations. The relationship between the measured and predicted values were analysed by correlation and regression analyses. The results indicated that the Tanaka and Johnston prediction equations were not fully applicable to the Black South African sample. The equations tended to underpredict the male sample, while slight overprediction was observed in the female sample. Therefore, new equations were formulated and proposed that would be accurate for Black subjects.

  9. Between-year survival and rank transitions in male Black-capped Chickadees (Poecile atricapillus) : A multistate modeling approach

    NARCIS (Netherlands)

    Schubert, Kristin A.; Mennill, Daniel J.; Ramsay, Scott M.; Otter, Ken A.; Ratcliffe, Laurene M.; Kraus, Cornelia

    In dominance-structured animal societies, variation in individual fitness is often related to social status. Like many passerine birds, Black-capped Chickadees (Poecile atricapillus) have a short average adult life-expectancy (similar to 2 years); however, the maximum recorded life span is >5x as

  10. Black hole levitron

    International Nuclear Information System (INIS)

    Arsiwalla, Xerxes D.; Verlinde, Erik P.

    2010-01-01

    We study the problem of spatially stabilizing four dimensional extremal black holes in background electric/magnetic fields. Whilst looking for stationary stable solutions describing black holes placed in external fields we find that taking a continuum limit of Denef et al.'s multicenter supersymmetric black hole solutions provides a supergravity description of such backgrounds within which a black hole can be trapped within a confined volume. This construction is realized by solving for a levitating black hole over a magnetic dipole base. We comment on how such a construction is akin to a mechanical levitron.

  11. Black Holes

    OpenAIRE

    Horowitz, Gary T.; Teukolsky, Saul A.

    1998-01-01

    Black holes are among the most intriguing objects in modern physics. Their influence ranges from powering quasars and other active galactic nuclei, to providing key insights into quantum gravity. We review the observational evidence for black holes, and briefly discuss some of their properties. We also describe some recent developments involving cosmic censorship and the statistical origin of black hole entropy.

  12. Inequality in Black and White High School Students' Perceptions of School Support: An Examination of Race in Context.

    Science.gov (United States)

    Bottiani, Jessika H; Bradshaw, Catherine P; Mendelson, Tamar

    2016-06-01

    Supportive relationships with adults at school are critical to student engagement in adolescence. Additional research is needed to understand how students' racial backgrounds interact with the school context to shape their perceptions of school support. This study employed multilevel, latent variable methods with a sample of Black and White students (N = 19,726, 35.8 % Black, 49.9 % male, mean age = 15.9) in 58 high schools to explore variation in perceived caring, equity, and high expectations by student race, school diversity, and socioeconomic context. The results indicated that Black students perceived less caring and equity relative to White students overall, and that equity and high expectations were lower in diverse schools for both Black and White students. Nonetheless, racial disparities were attenuated in more diverse schools. The findings point to the need for intervention to improve perceptions of school support for Black youth and for all students in lower income and more diverse schools.

  13. Brain nonapeptide and gonadal steroid responses to deprivation of heterosexual contact in the black molly

    Directory of Open Access Journals (Sweden)

    Ewa Kulczykowska

    2014-12-01

    Full Text Available Fish may respond to different social situations with changes in both physiology and behaviour. A unique feature of fish is that social interactions between males and females strongly affect the sexual characteristics of individuals. Here we provide the first insight into the endocrine background of two phenomena that occur in mono-sex groups of the black molly (Poecilia sphenops: masculinization in females and same-sex sexual behaviour, manifested by gonopodial displays towards same-sex tank mates and copulation attempts in males. In socially controlled situations, brain neurohormones impact phenotypic sex determination and sexual behaviour. Among these hormones are the nonapeptides arginine vasotocin (AVT and isotocin (IT, counterparts of the well-known mammalian arginine vasopressin and oxytocin, respectively. To reveal potential hormone interactions, we measured the concentrations of bioactive AVT and IT in the brain, along with those of the sex steroids 17β-estradiol and 11-ketotestosterone in the gonads, of females, masculinized females, males displaying same-sex sexual behaviour and those who did not. These data were supplemented by morphological and histological analyses of the gonads. Correlations between brain nonapeptides and gonadal steroids strongly suggest a cross talk between hormonal systems. In the black molly, the masculinization process was associated with the production of brain AVT and gonadal steroids, whereas same-sex sexual behaviour involves both brain nonapeptides, but neither of the sex steroids. This study extends current knowledge of endocrine control of phenotypic sex and sexual behaviour in fish and for the first time links brain nonapeptides with the occurrence of male-male sexual behaviour in lower vertebrates.

  14. Search for black holes

    International Nuclear Information System (INIS)

    Cherepashchuk, Anatolii M

    2003-01-01

    Methods and results of searching for stellar mass black holes in binary systems and for supermassive black holes in galactic nuclei of different types are described. As of now (June 2002), a total of 100 black hole candidates are known. All the necessary conditions Einstein's General Relativity imposes on the observational properties of black holes are satisfied for candidate objects available, thus further assuring the existence of black holes in the Universe. Prospects for obtaining sufficient criteria for reliably distinguishing candidate black holes from real black holes are discussed. (reviews of topical problems)

  15. BLACK TEA INFUSION AMELIORATES ENZYMATIC CHANGES INDUCED BY SUBCUTANEOUS EXPOSURE OF GASOLINE AND GM-10 IN MICE

    OpenAIRE

    Manjeet Dave; Ramtej Jayram Verma

    2017-01-01

    The present study was carried out to examine the ameliorative effect of black tea infusion on gasoline and GM-10 induced enzymatic changes in kidney of mice. Eighty healthy adult Swiss strain male albino mice weighing 32-35 gm were divided into eight groups including untreated control and various treated groups. Treated groups were subcutaneously administered with gasoline (412 mg/kg/day) and GM-10 low dose (206 mg/kg/day) and high dose (412 mg/kg/day) for 30 days. Black tea infusion (2%) was...

  16. Noncommutative black holes

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-DomInguez, J C [Instituto de Fisica de la Universidad de Guanajuato PO Box E-143, 37150 Leoen Gto. (Mexico); Obregon, O [Instituto de Fisica de la Universidad de Guanajuato PO Box E-143, 37150 Leoen Gto. (Mexico); RamIrez, C [Facultad de Ciencias FIsico Matematicas, Universidad Autonoma de Puebla, PO Box 1364, 72000 Puebla (Mexico); Sabido, M [Instituto de Fisica de la Universidad de Guanajuato PO Box E-143, 37150 Leoen Gto. (Mexico)

    2007-11-15

    We study noncommutative black holes, by using a diffeomorphism between the Schwarzschild black hole and the Kantowski-Sachs cosmological model, which is generalized to noncommutative minisuperspace. Through the use of the Feynman-Hibbs procedure we are able to study the thermodynamics of the black hole, in particular, we calculate Hawking's temperature and entropy for the 'noncommutative' Schwarzschild black hole.

  17. Who Is Whistling Vivaldi? How Black Football Players Engage with Stereotype Threats in College

    Science.gov (United States)

    Griffin, Whitney

    2017-01-01

    In light of the impact of negative stereotypes on student-athlete academic performance, the purpose of this paper was to conduct a qualitative study that examined how Black American male football players engage and cope with negative stereotypes at a predominantly White institution. Data were collected and analyzed from semi-structured interviews…

  18. Black hole critical phenomena without black holes

    Indian Academy of Sciences (India)

    large values of Ф, black holes do form and for small values the scalar field ... on the near side of the ridge ultimately evolve to form black holes while those configu- ... The inset shows a bird's eye view looking down on the saddle point.

  19. Black widow spider

    Science.gov (United States)

    ... medlineplus.gov/ency/article/002858.htm Black widow spider To use the sharing features on this page, please enable JavaScript. The black widow spider (Latrodectus) has a shiny black body with a ...

  20. The role of black rice (Oryza sativa L.) in the control of hypercholesterolemia in rats.

    Science.gov (United States)

    Salgado, Jocelem Mastrodi; Oliveira, Anderson Giovanni Candido de; Mansi, Débora Niero; Donado-Pestana, Carlos M; Bastos, Candido Ricardo; Marcondes, Fernanda Klein

    2010-12-01

    Cardiovascular disease is a serious public health problem; it is the first "cause of death" in Brazil and in developed countries. Thus, it is essential to search for alternative sources such as some functional foods to prevent and control the risks of this disease. The purpose of this study was to evaluate the lipidemic parameters in hypercholesterolemic rats fed diets containing black rice variety IAC 600 or unrefined rice. Adult male Wistar rats (Rattus norvegicus var. albinos) were used, weighing about 200-220 g. The animals were divided into four groups: the first received a control casein diet, the second received hypercholesterolemic diet, and the other two groups, after induction of hypercholesterolemia, received the test diets, the first containing 20% black rice and the second 20% unrefined, for 30 days. It was observed that diet containing black rice reduced the level of plasma cholesterol, triglycerides, and low-density lipoprotein. For high-density lipoprotein values, the diet that provided an increase in the levels was the black rice. The diet containing black rice was more effective in controlling the lipidemia in rats compared with the whole rice diet.

  1. Demographic characteristics associated with homelessness and risk among female and male veterans accessing VHA outpatient care.

    Science.gov (United States)

    Montgomery, Ann Elizabeth; Dichter, Melissa E; Thomasson, Arwin M; Fu, Xiaoying; Roberts, Christopher B

    2015-01-01

    This study explored demographic influences on veterans' reports of homelessness or imminent risk of homelessness with a particular focus on gender. We analyzed data for a cohort of veterans who responded to the U.S. Department of Veterans Affairs (VA), Veterans Health Administration (VHA) universal screener for homelessness and risk during a 3-month period. Multinomial mixed effects models-stratified by gender-predicted veterans' reports of homelessness or risk based on age, race, marital status, and receipt of VA compensation. The proportion of positive screens-homelessness or risk-was 2.7% for females and 1.7% for males. Women more likely to report being at risk of homelessness were aged 35 to 54 years, Black, and unmarried; those more likely to experience homelessness were Black and unmarried. Among male veterans, the greatest predictors of both homelessness and risk were Black race and unmarried status. Among both genders, receiving VA disability compensation was associated with lesser odds of being homeless or at risk. The findings describe the current population of veterans using VHA health care services who may benefit from homelessness prevention or intervention services, identify racial differences in housing stability, and distinguish subpopulations who may be in particular need of intervention. Interventions to address these needs are described. Published by Elsevier Inc.

  2. Pleasure, affection, and love among Black men who have sex with men (MSM) versus MSM of other races: countering dehumanizing stereotypes via cross-race comparisons of reported sexual experience at last sexual event.

    Science.gov (United States)

    Calabrese, Sarah K; Rosenberger, Joshua G; Schick, Vanessa R; Novak, David S

    2015-10-01

    Black men have historically been stereotyped as hedonistic, aggressive, and animalistic in their sexual interactions. This study sought to describe pleasure, affection, and love experienced by Black men who have sex with men (MSM) during their last male-partnered sexual event and to examine differences relative to White, Latino, and Asian MSM. A total of 21,696 (793 Black, 18,905 White, 1,451 Latino, and 547 Asian) U.S. men ages 18-87 (M Age = 39) were recruited from social/sexual networking sites targeting MSM in 2010-2011. Participants reported multiple dimensions of sexual experience (pleasure, affection, and love) occurring at their last male-partnered sexual event, partner relationship, and sociodemographic characteristics. Across relationship categories, a sizeable percentage of Black MSM reported pleasure (72-87  % orgasmed, 57-82 % experienced high subjective pleasure) and affection (70-91 % kissed, 47-90 % cuddled). Love was primarily reported for events involving main partners (felt love for partner: 96 %; felt loved by partner: 97 %; verbalized love to partner: 89 %). Latent class analysis with MSM of all races, adjusting for partner relationship and sociodemographic characteristics, revealed three distinct profiles of sexual experience: affection and love (Class 1); affection in the absence of love (Class 2); and neither affection nor love (Class 3). Pleasure was probable across profiles. Some racial differences in profile probability were present, but no overall pattern emerged. Contrary to Black male stereotypes, Black MSM commonly reported pleasure, affection, and love at their last male-partnered sexual event and did not show a meaningful pattern of difference from other-race MSM in their likelihood of experiencing all three.

  3. A Dancing Black Hole

    Science.gov (United States)

    Shoemaker, Deirdre; Smith, Kenneth; Schnetter, Erik; Fiske, David; Laguna, Pablo; Pullin, Jorge

    2002-04-01

    Recently, stationary black holes have been successfully simulated for up to times of approximately 600-1000M, where M is the mass of the black hole. Considering that the expected burst of gravitational radiation from a binary black hole merger would last approximately 200-500M, black hole codes are approaching the point where simulations of mergers may be feasible. We will present two types of simulations of single black holes obtained with a code based on the Baumgarte-Shapiro-Shibata-Nakamura formulation of the Einstein evolution equations. One type of simulations addresses the stability properties of stationary black hole evolutions. The second type of simulations demonstrates the ability of our code to move a black hole through the computational domain. This is accomplished by shifting the stationary black hole solution to a coordinate system in which the location of the black hole is time dependent.

  4. "It ain't all as bad as it may seem": young Black lesbians' responses to sexual prejudice.

    Science.gov (United States)

    Reed, Sarah J; Valenti, Maria T

    2012-01-01

    This article explores the ways in which young, Black lesbians manage their sexual minority identity when experiencing sexual prejudice. Fourteen Black lesbians between the ages of 16 and 24 participated in semistructured interviews. Instances of sexual prejudice and the young women's responses were thematically analyzed using open and axial qualitative coding techniques. Results indicated that participants experienced sexual prejudice frequently and even within the lesbian community. Responses to sexual prejudice included: cognitive reframing of heterosexist messages, passing, gaining support from self-created gay families, and fighting back (physically and verbally) in the event of isolated instances of sexual prejudice. Analysis focuses on how gender identity relates to experiences of sexual prejudice and identity management strategies. Findings suggest that there are parallels between the management strategies of these women and young, Black gay and bisexual males and between these women and Black women who are coping with sexism and racism.

  5. Sex, Diet, and the Social Environment: Factors Influencing Hair Cortisol Concentration in Free-Ranging Black Bears (Ursus americanus).

    Science.gov (United States)

    Lafferty, Diana J R; Laudenslager, Mark L; Mowat, Garth; Heard, Doug; Belant, Jerrold L

    2015-01-01

    Increasingly, measures of glucocorticoid levels (e.g., cortisol), key components of the neuroendocrine stress axis, are being used to measure past hypothalamic-pituitary-adrenal (HPA) activity to index psychological and physiological stress exhibited by wildlife for assessing individual and population-level well-being. However, many intrinsic and extrinsic factors affect HPA activity in animals. Using American black bears (Ursus americanus; n = 116) as an ecological model and hair cortisol concentration (HCC) as an integrative measure of past HPA activity, we evaluated the influence of diet, sex and the social environment on black bear HCC in a free-ranging population that spanned adjoining ecoregions with differing densities of potential conspecific and heterospecific competitors. HCC varied by sex, with female HCC ranging from 0.6 to 10.7 pg/mg (median = 4.5 ± 1.2 mean absolute deviation [MAD]) and male HCC ranging from 0.5 to 35.1 pg/mg (median = 6.2 ± 2.6 MAD). We also observed a three-way interaction among sex, δ14C and ecoregion, which may indicate that some differences in HCC between female and male black bears results from variability in the nutritional needs of larger-bodied males relative to smaller-bodied females, slight differences in food resources use between ecoregions as well as sex-based differences regarding the social environment. Once we understand what drives sex-specific differences in HCC, HCC may aid our understanding of the physiological responses by bears and other wildlife to diverse environmental challenges.

  6. Phylogenetic relationships among Brazilian howler monkeys, genus Alouatta (Platyrrhini, Atelidae, based on g1-globin pseudogene sequences

    Directory of Open Access Journals (Sweden)

    Carla Maria Meireles

    1999-09-01

    Full Text Available The genus Alouatta (howler monkeys is the most widely distributed of New World primates, and has been arranged in three species groups: the Central American Alouatta palliata group and the South American Alouatta seniculus and Alouatta caraya groups. While the latter is monotypic, the A. seniculus group encompasses at least three species (A. seniculus, A. belzebul and A. fusca. In the present study, approximately 600 base pairs of the g1-globin pseudogene were sequenced in the four Brazilian species (A. seniculus, A. belzebul, A. fusca and A. caraya. Maximum parsimony and maximum likelihood methods yielded phylogenetic trees with the same arrangement: {A. caraya [A. seniculus (A. fusca, A. belzebul]}. The most parsimonious tree had bootstrap values greater than 82% for all groupings, and strength of grouping values of at least 2, supporting the sister clade of A. fusca and A. belzebul. The study also confirmed the presence of a 150-base pair Alu insertion element and a 1.8-kb deletion in the g1-globin pseudogene in A. fusca, features found previously in the remaining three species. The cladistic classification based on molecular data agrees with those of morphological studies, with the monospecific A. caraya group being clearly differentiated from the A. seniculus group.Os guaribas, do gênero Alouatta, que são os primatas do Novo Mundo com maior distribuição geográfica, têm sido colocados em três grupos de espécies: o grupo Alouatta palliata da América central, e os grupos sulamericanos Alouatta seniculus e Alouatta caraya. Este último é monotípico, mas o grupo A. seniculus inclui pelo menos três espécies (A. seniculus, A. belzebul e A. fusca. Neste estudo, foram seqüenciados aproximadamente 600 pares de base do pseudogene globina g1 nas quatro espécies brasileiras (A. seniculus, A. belzebul, A. fusca e A. caraya. Os métodos de máxima parcimônia e máxima verossimilhança produziram árvores filogenéticas com o mesmo arranjo

  7. Black bears in Arkansas: Characteristics of a successful translocation

    Science.gov (United States)

    Smith, Kimberly G.; Clark, Joseph D.

    1994-01-01

    In 1958, the Arkansas Game and Fish Commission began translocating black bears (Ursus americanus) from Minnesota to the Interior Highlands (Ozark and Ouachita mountains) of Arkansas where bears had been extirpated early in this century. This project continued for 11 years with little public imput, during which time an estimated 254 bears were released. We estimate there are now >2,500 bears in the Interior Highlands of Arkansas, Missouri, and Oklahoma, making it one of the most successful translocations of a Carnivora. Factors that contributed to the success include use of wild-captured animals, elimination of major factors associated with extirpation, release into prime habitats within the former range, multiple release sites, release of 20–40 animals/year for eight years, and release of mostly males prior to release of mostly females. Studies on two allopatric populations demonstrate that they are now diverging in some demographic characteristics, including litter size, cub survivorship, and adult sex-ratio. Translocation of black bears to the Interior Highlands is successful in terms of numbers of animals, but it will not be truly successful until people accept black bears as part of the regional fauna. To that end, those associated with management and research of bears in Arkansas are now focussing on public education and control of nuisance bears.

  8. Visible and Invisible Trends in Black Men's Health: Pitfalls and Promises for Addressing Racial, Ethnic, and Gender Inequities in Health.

    Science.gov (United States)

    Gilbert, Keon L; Ray, Rashawn; Siddiqi, Arjumand; Shetty, Shivan; Baker, Elizabeth A; Elder, Keith; Griffith, Derek M

    2016-01-01

    Over the past two decades, there has been growing interest in improving black men's health and the health disparities affecting them. Yet, the health of black men consistently ranks lowest across nearly all groups in the United States. Evidence on the health and social causes of morbidity and mortality among black men has been narrowly concentrated on public health problems (e.g., violence, prostate cancer, and HIV/AIDS) and determinants of health (e.g., education and male gender socialization). This limited focus omits age-specific leading causes of death and other social determinants of health, such as discrimination, segregation, access to health care, employment, and income. This review discusses the leading causes of death for black men and the associated risk factors, as well as identifies gaps in the literature and presents a racialized and gendered framework to guide efforts to address the persistent inequities in health affecting black men.

  9. African American Male College Students Navigate to Achieve: The Relationship among College Adjustment Experiences, Coping, and GPA for Black Males at Two Predominantly White Institutions

    Science.gov (United States)

    Walters, Sabrina Denise

    2017-01-01

    African American males face daunting obstacles as they pursue higher education as research has shown. This study sought to better understand the impact of specific factors--social support, racial identity, perceived racial discrimination, coping, and religious coping--on the academic achievement of African American male college student…

  10. Skeletal Myocyte Types and Vascularity in the Black Sicilian Pig

    Directory of Open Access Journals (Sweden)

    S. Velotto

    2007-01-01

    Full Text Available The objective of this study was to verify the presence of giant fibres in the Black Sicilian pig skeletal muscle and to evaluate the effect of sex on histochemical and morphometric characteristics of the myocytes (myofibres as well as vascularity of the muscle. Twenty Black Sicilian pigs (10 males, 10 females from a farm in Sicily (Italy were slaughtered at two years of age. Muscle tissues were obtained from three muscles: psoas major, longissimus dorsi, and trapezius. Myofibres were stained for myosin ATPase, succinic dehydrogenase, and α-amylase-PAS. For all fibre types, area and perimeter were measured. Slow-twitch oxidative fibres, fast-twitch glycolytic fibres and fast-twitch oxidative-glycolytic fibres were histochemically differentiated; an image-analyzing system was used. The results showed no differences between males and females in percentage of the fibre types, but there were significant differences between sexes in size of all the three fibre types. Psoas major muscle had a high percentage of slow-twitch oxidative fibres and contained more capillaries per fibre and per mm2 than trapezius and longissimus dorsi, in which fast-twitch glycolytic fibres dominated. The cross-sectional area of all fibres types was larger in longissimus dorsi than in trapezius and psoas major muscles; the giant fibres were absent in all the muscles studied. Fibre type composition may contribute to the variation of meat quality.

  11. Astrophysical black holes

    CERN Document Server

    Gorini, Vittorio; Moschella, Ugo; Treves, Aldo; Colpi, Monica

    2016-01-01

    Based on graduate school lectures in contemporary relativity and gravitational physics, this book gives a complete and unified picture of the present status of theoretical and observational properties of astrophysical black holes. The chapters are written by internationally recognized specialists. They cover general theoretical aspects of black hole astrophysics, the theory of accretion and ejection of gas and jets, stellar-sized black holes observed in the Milky Way, the formation and evolution of supermassive black holes in galactic centers and quasars as well as their influence on the dynamics in galactic nuclei. The final chapter addresses analytical relativity of black holes supporting theoretical understanding of the coalescence of black holes as well as being of great relevance in identifying gravitational wave signals. With its introductory chapters the book is aimed at advanced graduate and post-graduate students, but it will also be useful for specialists.

  12. An analysis of job placement patterns of black and non-black male and female undergraduates at the University of Virginia and Hampton Institute. Ph.D. Thesis - Virginia Univ.

    Science.gov (United States)

    Anderson, A. F.

    1974-01-01

    Research questions were proposed to determine the relationship between independent variables (race, sex, and institution attended) and dependent variables (number of job offers received, salary received, and willingness to recommend source of employer contact). The control variables were academic major, grade point average, placement registration, nonemployment activity, employer, and source of employer contact. An analysis of the results revealed no statistical significance of the institution attended as a predictor of job offers or salary, although significant relationships were found between race and sex and number of job offers received. It was found that academic major, grade point average, and source of employer contact were more useful than race in the prediction of salary. Sex and nonemployment activity were found to be the most important variables in the model. The analysis also indicated that Black students received more job offers than non-Black students.

  13. Lumpy AdS5× S5 black holes and black belts

    International Nuclear Information System (INIS)

    Dias, Óscar J.C.; Santos, Jorge E.; Way, Benson

    2015-01-01

    Sufficiently small Schwarzschild black holes in global AdS 5 ×S 5 are Gregory-Laflamme unstable. We construct new families of black hole solutions that bifurcate from the onset of this instability and break the full SO(6) symmetry group of the S 5 down to SO(5). These new “lumpy" solutions are labelled by the harmonics ℓ. We find evidence that the ℓ=1 branch never dominates the microcanonical/canonical ensembles and connects through a topology-changing merger to a localised black hole solution with S 8 topology. We argue that these S 8 black holes should become the dominant phase in the microcanonical ensemble for small enough energies, and that the transition to Schwarzschild black holes is first order. Furthermore, we find two branches of solutions with ℓ=2. We expect one of these branches to connect to a solution containing two localised black holes, while the other branch connects to a black hole solution with horizon topology S 4 ×S 4 which we call a “black belt”.

  14. Black holes in binary stars

    NARCIS (Netherlands)

    Wijers, R.A.M.J.

    1996-01-01

    Introduction Distinguishing neutron stars and black holes Optical companions and dynamical masses X-ray signatures of the nature of a compact object Structure and evolution of black-hole binaries High-mass black-hole binaries Low-mass black-hole binaries Low-mass black holes Formation of black holes

  15. Black-footed ferret areas of activity during late summer and fall at Meeteetse, Wyoming

    Science.gov (United States)

    Fagerstone, K.A.; Biggins, D.E.

    2011-01-01

    Radiotelemetry was used during 1983 and 1984 to collect information on short-term areas of activity for black-footed ferrets (Mustela nigripes) near Meeteetse, Wyoming. This population ultimately provided ferrets for the captive-breeding program that bred and released offspring into the wild since 1991. We fitted 5 adult ferrets and 13 juveniles with radiotransmitters and followed their movements during late summer and fall. Adult males had 7-day areas of activity that were >6 times as large as those of adult females. Activity areas of adult males varied little in coverage or location on a weekly basis, but females sequentially shifted their areas. Unlike juvenile females, juvenile males tended to leave their natal colonies. ?? 2011 American Society of Mammalogists.

  16. Black Interpretation, Black American Literature, and Grey Audiences.

    Science.gov (United States)

    Washington, Earl M.

    1981-01-01

    Defines and illustrates language techniques used by Black authors writing to and for Blacks in the 1960s and 1970s. Suggests how language and theme barriers of such literature might be overcome in a contemporary integrated oral interpretation classroom. (PD)

  17. Foraging strategy of a Neotropical primate: how intrinsic and extrinsic factors influence destination and residence time

    DEFF Research Database (Denmark)

    Plante, Sabrina; Colchero, Fernando; Calmé, Sophie

    2014-01-01

    accounting for intrinsic and extrinsic factors, which are often overlooked when modelling foraging behaviour. 2.We identified the decision rules for foraging in black howler monkeys (Alouatta pigra), according to food preferences, locations of high quality patches and previously eaten trees, phenology...... of food resources and hunger state. We depicted foraging in two stages: 1) the choice of the immediate next tree and 2) the time spent on this tree. We used a recently developed model for inference of movement processes, incorporating resource selection functions into a Markov Chain framework. 3.We found...... that monkeys tend to move to preferred tree species at each step. However, we did not find conclusively that, at each step, monkeys direct their movements to reach high-quality patches. In fact, they were using these patches intensively, thus limiting the possibility to move toward other high quality patches...

  18. #BlackBabiesMatter: Analyzing Black Religious Media in Conservative and Progressive Evangelical Communities

    Directory of Open Access Journals (Sweden)

    Monique Moultrie

    2017-11-01

    Full Text Available This article explores how conservative and progressive black Protestants interrogate the theological theme of the sacrality of black life through digital media. The innovations of religious media in black evangelical communities remain an understudied phenomenon in African American religion, making this an apt arena for further discovery. This current intervention into the study of African American Religion examines digital activism through examples of religious media produced by blacks for black audiences. This article begins its interrogation of the sacrality of black life by juxtaposing those who contend that Black Babies Matter as pro-birth-oriented, religiously motivated activists with those religious opponents asserting Black Lives Matter who present an intersectional pro-life approach. The comparison of views relies on womanist cultural analysis as its main methodology to analyze and interpret digital media and explore its ramifications for African American Religion.

  19. Black holes. Chapter 6

    International Nuclear Information System (INIS)

    Penrose, R.

    1980-01-01

    Conditions for the formation of a black hole are considered, and the properties of black holes. The possibility of Cygnus X-1 as a black hole is discussed. Einstein's theory of general relativity in relation to the formation of black holes is discussed. (U.K.)

  20. Aqueous and hydroalcoholic extracts of Black Maca (Lepidium meyenii) improve scopolamine-induced memory impairment in mice.

    Science.gov (United States)

    Rubio, Julio; Dang, Haixia; Gong, Mengjuan; Liu, Xinmin; Chen, Shi-Lin; Gonzales, Gustavo F

    2007-10-01

    Lepidium meyenii Walp. (Brassicaceae), known as Maca, is a Peruvian hypocotyl growing exclusively between 4,000 and 4,500 m altitude in the central Peruvian Andes, particularly in Junin plateau. Previously, Black variety of Maca showed to be more beneficial than other varieties of Maca on learning and memory in ovariectomized mice on the water finding test. The present study aimed to test two different doses of aqueous (0.50 and 2.00 g/kg) and hydroalcoholic (0.25 and 1.00 g/kg) extracts of Black Maca administered for 35 days on memory impairment induced by scopolamine (1mg/kg body weight i.p.) in male mice. Memory and learning were evaluated using the water Morris maze and the step-down avoidance test. Brain acetylcholinesterase (AChE) and monoamine oxidase (MAO) activities in brain were also determined. Both extracts of Black Maca significantly ameliorated the scopolamine-induced memory impairment as measured in both the water Morris maze and the step-down avoidance tests. Black Maca extracts inhibited AChE activity, whereas MAO activity was not affected. These results indicate that Black Maca improves scopolamine-induced memory deficits.

  1. Black ringoids: spinning balanced black objects in d≥5 dimensions — the codimension-two case

    International Nuclear Information System (INIS)

    Kleihaus, Burkhard; Kunz, Jutta; Radu, Eugen

    2015-01-01

    We propose a general framework for the study of asymptotically flat black objects with k+1 equal magnitude angular momenta in d≥5 spacetime dimensions (with 0≤k≤[((d−5)/2)]). In this approach, the dependence on all angular coordinates but one is factorized, which leads to a codimension-two problem. This framework can describe black holes with spherical horizon topology, the simplest solutions corresponding to a class of Myers-Perry black holes. A different set of solutions describes balanced black objects with S"n"+"1×S"2"k"+"1 horizon topology. The simplest members of this family are the black rings (k=0). The solutions with k>0 are dubbed black ringoids. Based on the nonperturbative numerical results found for several values of (n,k), we propose a general picture for the properties and the phase diagram of these solutions and the associated black holes with spherical horizon topology: n=1 black ringoids repeat the k=0 pattern of black rings and Myers-Perry black holes in 5 dimensions, whereas n>1 black ringoids follow the pattern of higher dimensional black rings associated with ‘pinched’ black holes and Myers-Perry black holes.

  2. Black theology in South Africa – A theology of human dignity and black identity

    Directory of Open Access Journals (Sweden)

    Timothy van Aarde

    2016-08-01

    Full Text Available Black theology in South Africa is still relevant 20 years after the apartheid regime ended. It is a theology that gave to Black South Africans human dignity and a black identity. Black theology in South Africa confronted the imbalances of power and abusive power structures through an affirmation of human dignity and the uniqueness of the identity of black people. The biblical narrative of the Exodus is a definitive narrative in American black theology and liberation theology in overcoming oppression understood as political victimisation. Black theology in South Africa is not primarily about power and economics but also about the rediscovery of human dignity and black identity and to a lesser extent about victimisation. A third generation of black theology in South Africa will gain impetus through a rediscovery of human dignity and identity as its core values instead of a Black American liberation theology of victimisation or a Marxist liberation theology of the eradication of all power or economic imbalances.

  3. Black hole hair removal

    International Nuclear Information System (INIS)

    Banerjee, Nabamita; Mandal, Ipsita; Sen, Ashoke

    2009-01-01

    Macroscopic entropy of an extremal black hole is expected to be determined completely by its near horizon geometry. Thus two black holes with identical near horizon geometries should have identical macroscopic entropy, and the expected equality between macroscopic and microscopic entropies will then imply that they have identical degeneracies of microstates. An apparent counterexample is provided by the 4D-5D lift relating BMPV black hole to a four dimensional black hole. The two black holes have identical near horizon geometries but different microscopic spectrum. We suggest that this discrepancy can be accounted for by black hole hair - degrees of freedom living outside the horizon and contributing to the degeneracies. We identify these degrees of freedom for both the four and the five dimensional black holes and show that after their contributions are removed from the microscopic degeneracies of the respective systems, the result for the four and five dimensional black holes match exactly.

  4. UH-60M Black Hawk Helicopter (UH-60M Black Hawk)

    Science.gov (United States)

    2016-12-01

    Selected Acquisition Report (SAR) RCS: DD-A&T(Q&A)823-341 UH-60M Black Hawk Helicopter (UH-60M Black Hawk ) As of FY 2017 President’s Budget Defense...Acquisition Management Information Retrieval (DAMIR) March 21, 2016 18:25:45 UNCLASSIFIED UH-60M Black Hawk December 2015 SAR March 21, 2016 18...Operational Requirements Document OSD - Office of the Secretary of Defense O&S - Operating and Support PAUC - Program Acquisition Unit Cost UH-60M Black Hawk

  5. Black American and Nigerian Pentecostalism: A Black Religious ...

    African Journals Online (AJOL)

    Black American and Nigerian Pentecostalism: A Black Religious Schizophrenia, 1910-2010. ... in American and African Pentecostalism as is related to social crisis, the dislocation of masses brought on by economic deprivation, urbanization, the break up of traditional society and consequence loss of traditional values.

  6. Black Tea

    Science.gov (United States)

    ... mental alertness as well as learning, memory, and information processing skills. It is also used for treating headache; ... of carbamazepine. Since black tea contains caffeine, in theory taking black tea with carbamazepine might decrease the ...

  7. Miss Evers' Boys (1997. Study of the spontaneous evolution of syphilis in black patients

    Directory of Open Access Journals (Sweden)

    Agustín del Cañizo Fernández-Roldán

    2008-10-01

    Full Text Available Miss Evers' Boys (1997 is a movie based on a real fact happened in the State of Alabama (United States, where it was carried out a research work that begun in 1932 and was prolonged up to 1972. It consisted on watching the evolution of syphilis in black male patients, who were not given any anti-syphilitic treatment at any moment. Once the fact was public, a great polemic on the ethics of the research with human fellows was originated and publications dealt with this case. The movie, faithful as for the bottom of the problem, it’s made as a novel about a research team’s nurse and four black participants patients.

  8. Seroprevalence of Toxoplasma gondii in American Black Bears ( Ursus americanus ) of the Central Appalachians, USA.

    Science.gov (United States)

    Cox, John J; Murphy, Sean M; Augustine, Ben C; Guthrie, Joseph M; Hast, John T; Maehr, Sutton C; McDermott, Joseph

    2017-07-01

    We assessed Toxoplasma gondii seroprevalence in 53 free-ranging American black bears ( Ursus americanus ) in the Central Appalachian Mountains, US. Seroprevalence was 62% with no difference between males and females or between juvenile and adult bears. Wildlife agencies should consider warnings in hunter education programs to reduce the chances for human infection from this source.

  9. Blacked Out: Racial and Gender Segregation in Gifted Education 60 Years after "Brown vs. Board of Education"

    Science.gov (United States)

    Ford, Donna Y.; King, Robert A., Jr.

    2014-01-01

    This article examines the under-representation of African American students in gifted education, with attention to how representation differs for Black males and females. We contend that social injustices (e.g., prejudice and discrimination) contribute to racially segregated gifted education classes (Ford, 2013b). For support, gifted…

  10. Reading John 7:53–8:11 as a narrative against male violence against women

    Directory of Open Access Journals (Sweden)

    Michael O'Sullivan

    2015-08-01

    Full Text Available Male violence against women is at shocking levels in South Africa. According to Faul, ‘A woman is killed by an intimate partner every eight hours, a probable underestimate because no perpetrator is identified in 20 percent of killings’, whilst ‘More than 30 percent of girls have been raped by the time they are 18’. Reeva Steenkamp’s killing by her partner, Oscar Pistorius, came ‘the day before she planned to wear black in a “Black Friday” protest against the country’s excruciatingly high number of rapes’ (Faul. The purpose of this article is to reread a key biblical text regarding male violence against women in order to highlight how Jesus would want us to respond to such violence. The text is John 7:53–8:11. The NRSV: Catholic Edition entitles the story ‘The woman caught in adultery’. However, this title is problematic as it can lead to misleading readings of the text, as I will show, and so I have given it a different title, namely ‘The woman threatened with stoning’.

  11. Low Family Support and Risk of Obesity among Black Youth: Role of Gender and Ethnicity.

    Science.gov (United States)

    Assari, Shervin; Caldwell, Cleopatra Howard

    2017-05-12

    Most studies on the role of family environment in developing risk of obesity among youth have focused on parenting behaviors that are directly involved in energy balance in regional, non-representative White samples. Using a national sample of ethnically diverse Black youth, the current study tested the association between low family support and risk of obesity. We also tested the heterogeneity of this association based on gender, ethnicity, and their intersection. We used data from the National Survey of American Life-Adolescent Supplement (NSAL-A), a national survey of Black adolescents in the United States. The study enrolled 1170 African American and Caribbean Black 13-17 year old youth. Obesity was defined based on the cutoff points of body mass index (BMI) appropriate for age and gender of youth. Family support was measured using a five-item measure that captured emotional and tangible social support. Age, gender, and ethnicity were also measured. Logistic regressions were utilized in the pooled sample, and also based on gender, ethnicity, and their intersection, to test the link between low family support and risk for obesity. In the pooled sample, low family support was not associated with an increased risk of obesity (OR = 1.35, 95% Confidence Interval (CI) = 0.96-1.89). The association between low family support and risk of obesity was, however, significant among African American females (OR = 1.60, 95% CI = 1.01-2.55). There was no association for African American males (OR = 1.26, 95% CI = 0.82-1.92), Caribbean Black males (OR = 0.68, 95% CI = 0.01-54.85), and Caribbean Black females (OR = 0.78, 95% CI = 0.42-1.44). In conclusion, policies and programs that enable African American families to provide additional family support may prevent obesity among African American female youth. Future research should test the efficacy of promoting family support as a tool for preventing obesity among African American female youth.

  12. Sex, Diet, and the Social Environment: Factors Influencing Hair Cortisol Concentration in Free-Ranging Black Bears (Ursus americanus)

    Science.gov (United States)

    Lafferty, Diana J. R.; Laudenslager, Mark L.; Mowat, Garth; Heard, Doug; Belant, Jerrold L.

    2015-01-01

    Increasingly, measures of glucocorticoid levels (e.g., cortisol), key components of the neuroendocrine stress axis, are being used to measure past hypothalamic-pituitary-adrenal (HPA) activity to index psychological and physiological stress exhibited by wildlife for assessing individual and population-level well-being. However, many intrinsic and extrinsic factors affect HPA activity in animals. Using American black bears (Ursus americanus; n = 116) as an ecological model and hair cortisol concentration (HCC) as an integrative measure of past HPA activity, we evaluated the influence of diet, sex and the social environment on black bear HCC in a free-ranging population that spanned adjoining ecoregions with differing densities of potential conspecific and heterospecific competitors. HCC varied by sex, with female HCC ranging from 0.6 to 10.7 pg/mg (median = 4.5 ± 1.2 mean absolute deviation [MAD]) and male HCC ranging from 0.5 to 35.1 pg/mg (median = 6.2 ± 2.6 MAD). We also observed a three-way interaction among sex, δ14C and ecoregion, which may indicate that some differences in HCC between female and male black bears results from variability in the nutritional needs of larger-bodied males relative to smaller-bodied females, slight differences in food resources use between ecoregions as well as sex-based differences regarding the social environment. Once we understand what drives sex-specific differences in HCC, HCC may aid our understanding of the physiological responses by bears and other wildlife to diverse environmental challenges. PMID:26529405

  13. Sex, Diet, and the Social Environment: Factors Influencing Hair Cortisol Concentration in Free-Ranging Black Bears (Ursus americanus.

    Directory of Open Access Journals (Sweden)

    Diana J R Lafferty

    Full Text Available Increasingly, measures of glucocorticoid levels (e.g., cortisol, key components of the neuroendocrine stress axis, are being used to measure past hypothalamic-pituitary-adrenal (HPA activity to index psychological and physiological stress exhibited by wildlife for assessing individual and population-level well-being. However, many intrinsic and extrinsic factors affect HPA activity in animals. Using American black bears (Ursus americanus; n = 116 as an ecological model and hair cortisol concentration (HCC as an integrative measure of past HPA activity, we evaluated the influence of diet, sex and the social environment on black bear HCC in a free-ranging population that spanned adjoining ecoregions with differing densities of potential conspecific and heterospecific competitors. HCC varied by sex, with female HCC ranging from 0.6 to 10.7 pg/mg (median = 4.5 ± 1.2 mean absolute deviation [MAD] and male HCC ranging from 0.5 to 35.1 pg/mg (median = 6.2 ± 2.6 MAD. We also observed a three-way interaction among sex, δ14C and ecoregion, which may indicate that some differences in HCC between female and male black bears results from variability in the nutritional needs of larger-bodied males relative to smaller-bodied females, slight differences in food resources use between ecoregions as well as sex-based differences regarding the social environment. Once we understand what drives sex-specific differences in HCC, HCC may aid our understanding of the physiological responses by bears and other wildlife to diverse environmental challenges.

  14. Morphometric variability of Arctodiaptomus salinus (Copepoda) in the Mediterranean-Black Sea region.

    Science.gov (United States)

    Anufriieva, Elena V; Shadrin, Nickolai V

    2015-11-18

    Inter-species variability in morphological traits creates a need to know the range of variability of characteristics in the species for taxonomic and ecological tasks. Copepoda Arctodiaptomus salinus, which inhabits water bodies across Eurasia and North Africa, plays a dominant role in plankton of different water bodies-from fresh to hypersaline. This work assesses the intra- and inter-population morphometric variability of A. salinus in the Mediterranean-Black Sea region and discusses some observed regularities. The variability of linear body parameters and proportions was studied. The impacts of salinity, temperature, and population density on morphological characteristics and their variability can manifest themselves in different ways at the intra- and inter-population levels. A significant effect of salinity, pH and temperature on the body proportions was not found. Their intra-population variability is dependent on temperature and salinity. Sexual dimorphism of A. salinus manifests in different linear parameters, proportions, and their variability. There were no effects of temperature, pH and salinity on the female/male parameter ratio. There were significant differences in the body proportions of males and females in different populations. The influence of temperature, salinity, and population density can be attributed to 80%-90% of intra-population variability of A. salinus. However, these factors can explain less than 40% of inter-population differences. Significant differences in the body proportions of males and females from different populations may suggest that some local populations of A. salinus in the Mediterranean-Black Sea region are in the initial stages of differentiation.

  15. Performance of Nellore males under different artificial shading levels in the feedlot

    Directory of Open Access Journals (Sweden)

    Diogo Alves da Costa Ferro

    2016-09-01

    Full Text Available The objective of this study was to evaluate the influence of artificial shading on weight gain and meat quality of male Nellore cattle in an intensive production system. The experiment was conducted in the experimental feedlot of the Course of Animal Science at Universidade Estadual de Goiás, from July to October 2014. Forty-eight male Nellore cattle with an average initial weight of 310 kg were kept in double 24-m2 stalls, in a total of 24 stalls. Of these, six were in the open air; six were covered with black shade netting of 30% light interception; six with black shade netting 50%; and six with black shade netting 80%, providing 6 m2 of shade per stall. The ration supplied to the animals and the orts left in the trough were weighed daily to determine intake, and the temperature-humidity index (THI was measured twice weekly. Animals were weighed for the first time at the start of the experiment, and then another three times until the end, which was followed by the slaughter and assessments of performance and meat quality. A difference (p 0.05 was observed for feed intake, initial weight, final weight, total weight gain, average daily weight gain, carcass yield, marbling, texture, fatness, backfat thickness, loin-eye area, color, thigh length and circumference, leg length and circumference, or carcass length between the animals on the different treatments. The use of artificial shading does not have a significant effect on performance or meat quality of feedlot Nellore cattle when the ambient temperature is within the thermal comfort zone.

  16. Culture Counts: Examining the Effectiveness of a Culturally Focused Empowerment Program for At-Risk Black Girls

    Science.gov (United States)

    Aston, Candice N.

    Traditionally, many of the problems experienced by Black girls were overshadowed by the ongoing crises facing Black Males. Although important, the focus on Blackness and masculinity often implicitly leaves young Black girls on the sidelines and fails to recognize their unique obstacles. Fortunately, there has been a new surge of social concern revolving around the plight of Black girls in the school system. New estimates report that Black girls are facing an educational crisis in regards to disproportionate discipline practices and academics (Morris, 2012). To date, there has been very limited research in regards to school-based interventions that have been designed to help Black girls explore both their cultural and gender identity. This is problematic because Black girls are constantly confronted with deeply embedded stereotypes that reinforce racial and gender biases both in and outside the classroom (Morris, 2007). A key protective factor of combating negative messages and racial adversity is developing a positive racial identity (Case & Robinson, 2003). To address this problem, a mixed-methods study was conducted to investigate the feasibility and effectiveness of implementing an 8-week cultural empowerment program based on the Sisters of Nia curriculum. Qualitative results indicated a significant improvement in the participants' racial identity and self-concept. In addition, single-subject data has found the Sisters of Nia curriculum to have a positive impact on verbal aggression, which was evidenced by a significant reduction in behavior for all four single-subject participants'. These findings serve as further support to incorporate culturally-based interventions at the school level.

  17. Black holes are warm

    International Nuclear Information System (INIS)

    Ravndal, F.

    1978-01-01

    Applying Einstein's theory of gravitation to black holes and their interactions with their surroundings leads to the conclusion that the sum of the surface areas of several black holes can never become less. This is shown to be analogous to entropy in thermodynamics, and the term entropy is also thus applied to black holes. Continuing, expressions are found for the temperature of a black hole and its luminosity. Thermal radiation is shown to lead to explosion of the black hole. Numerical examples are discussed involving the temperature, the mass, the luminosity and the lifetime of black mini-holes. It is pointed out that no explosions corresponding to the prediction have been observed. It is also shown that the principle of conservation of leptons and baryons is broken by hot black holes, but that this need not be a problem. The related concept of instantons is cited. It is thought that understanding of thermal radiation from black holes may be important for the development of a quantified gravitation theory. (JIW)

  18. Is It because I'm Black? A Black Female Research Experience

    Science.gov (United States)

    Maylor, Uvanney

    2009-01-01

    This article examines what it means to be a Black female researcher in contemporary Britain. Drawing on Black feminist theory and critical race theory (CRT), this article seeks to highlight some of the experiences and challenges that Black female researchers face when undertaking research, particularly research that has diversity, equality or…

  19. Effects of gamma radiation on reproductive potential of the black cut worm, agrotis ipsilon (hufn. )

    Energy Technology Data Exchange (ETDEWEB)

    Sallam, H A; Elnagar, S; Ibrahim, S M

    1991-01-01

    Full grown pupae of the black cut worm, agrotis ipsilon were irradiated with 5, 10, 15, 30 and 35 krad of gamma radiation for males and with 5, 10, 15, 20 and 25 krad for females. The emerged adults were paired with the untreated opposite sex. Both the percentage of mated females and the average number of spermatophores per mated female decreased by irradiating male pupae with 20 krad and above. percentage of inseminated mated females decreased at the dose 15 krad and the reduction increased with increasing the gamma dose. Fecundity of female paired with irradiated male was decreased gradually with increasing the dose. A severe reduction in fecundity was obtained, in the case of irradiated female pupae. Egg hatch was also dose dependent, as it decreased with the increase in the radiation dose. Females were more radiosensitive than males, as far as reduction in hatchability was concerned. The sterilizing doses ranged between 30-35 and 15-20 krad for males and females, respectively.

  20. Effects of gamma radiation on reproductive potential of the black cut worm, agrotis ipsilon (hufn.)

    International Nuclear Information System (INIS)

    Sallam, H.A.; Elnagar, S.; Ibrahim, S.M.

    1991-01-01

    Full grown pupae of the black cut worm, agrotis ipsilon were irradiated with 5, 10, 15, 30 and 35 krad of gamma radiation for males and with 5, 10, 15, 20 and 25 krad for females. The emerged adults were paired with the untreated opposite sex. Both the percentage of mated females and the average number of spermatophores per mated female decreased by irradiating male pupae with 20 krad and above. percentage of inseminated mated females decreased at the dose 15 krad and the reduction increased with increasing the gamma dose. Fecundity of female paired with irradiated male was decreased gradually with increasing the dose. A severe reduction in fecundity was obtained, in the case of irradiated female pupae. Egg hatch was also dose dependent, as it decreased with the increase in the radiation dose. Females were more radiosensitive than males, as far as reduction in hatchability was concerned. The sterilizing doses ranged between 30-35 and 15-20 krad for males and females, respectively

  1. Sexually dimorphic aggression indicates male gray wolves specialize in pack defense against conspecific groups.

    Science.gov (United States)

    Cassidy, Kira A; Mech, L David; MacNulty, Daniel R; Stahler, Daniel R; Smith, Douglas W

    2017-03-01

    Aggression directed at conspecific groups is common among gregarious, territorial species, and for some species such as gray wolves (Canis lupus) intraspecific strife is the leading cause of natural mortality. Each individual in a group likely has different measures of the costs and benefits associated with a group task, such as an aggressive attack on another group, which can alter motivation and behavior. We observed 292 inter-pack aggressive interactions in Yellowstone National Park between 1 April 1995 and 1 April 2011 (>5300days of observation) in order to determine the role of both sexes, and the influence of pack, age, and other traits on aggression. We recorded the behaviors and characteristics of all individuals present during the interactions (n=534 individuals) and which individuals participated in each step (i.e. chase, attack, kill, flight) of the interaction. Overall, all wolves were more likely to chase rivals if they outnumbered their opponent, suggesting packs accurately assess their opponent's size during encounters and individuals adjust their behavior based on relative pack size. Males were more likely than females to chase rival packs and gray-colored wolves were more aggressive than black-colored wolves. Male wolves and gray-colored wolves also recorded higher cortisol levels than females and black-colored wolves, indicating hormonal support for more intense aggressive behavior. Further, we found a positive correlation between male age and probability of chasing, while age-specific participation for females remained constant. Chasing behavior was influenced by the sex of lone intruders, with males more likely to chase male intruders. This difference in behavior suggests male and female wolves may have different strategies and motivations during inter-pack aggressive interactions related to gray wolf mating systems. A division of labor between pack members concerning resource and territory defense suggests selection for specific traits related

  2. Sexually dimorphic aggression indicates male gray wolves specialize in pack defense against conspecific groups

    Science.gov (United States)

    Cassidy, Kira A.; Mech, L. David; MacNulty, Daniel R; Stahler, Daniel R.; Smith, Douglas W.

    2017-01-01

    Aggression directed at conspecific groups is common among gregarious, territorial species, and for some species such as gray wolves (Canis lupus) intraspecific strife is the leading cause of natural mortality. Each individual in a group likely has different measures of the costs and benefits associated with a group task, such as an aggressive attack on another group, which can alter motivation and behavior. We observed 292 inter-pack aggressive interactions in Yellowstone National Park between 1 April 1995 and 1 April 2011 (>5300 days of observation) in order to determine the role of both sexes, and the influence of pack, age, and other traits on aggression. We recorded the behaviors and characteristics of all individuals present during the interactions (n = 534 individuals) and which individuals participated in each step (i.e. chase, attack, kill, flight) of the interaction. Overall, all wolves were more likely to chase rivals if they outnumbered their opponent, suggesting packs accurately assess their opponent’s size during encounters and individuals adjust their behavior based on relative pack size. Males were more likely than females to chase rival packs and gray-colored wolves were more aggressive than black-colored wolves. Male wolves and gray-colored wolves also recorded higher cortisol levels than females and black-colored wolves, indicating hormonal support for more intense aggressive behavior. Further, we found a positive correlation between male age and probability of chasing, while age-specific participation for females remained constant. Chasing behavior was influenced by the sex of lone intruders, with males more likely to chase male intruders. This difference in behavior suggests male and female wolves may have different strategies and motivations during inter-pack aggressive interactions related to gray wolf mating systems. A division of labor between pack members concerning resource and territory defense suggests selection for specific traits

  3. Density of American black bears in New Mexico

    Science.gov (United States)

    Gould, Matthew J.; Cain, James W.; Roemer, Gary W.; Gould, William R.; Liley, Stewart

    2018-01-01

    Considering advances in noninvasive genetic sampling and spatially explicit capture–recapture (SECR) models, the New Mexico Department of Game and Fish sought to update their density estimates for American black bear (Ursus americanus) populations in New Mexico, USA, to aide in setting sustainable harvest limits. We estimated black bear density in the Sangre de Cristo, Sandia, and Sacramento Mountains, New Mexico, 2012–2014. We collected hair samples from black bears using hair traps and bear rubs and used a sex marker and a suite of microsatellite loci to individually genotype hair samples. We then estimated density in a SECR framework using sex, elevation, land cover type, and time to model heterogeneity in detection probability and the spatial scale over which detection probability declines. We sampled the populations using 554 hair traps and 117 bear rubs and collected 4,083 hair samples. We identified 725 (367 male, 358 female) individuals. Our density estimates varied from 16.5 bears/100 km2 (95% CI = 11.6–23.5) in the southern Sacramento Mountains to 25.7 bears/100 km2 (95% CI = 13.2–50.1) in the Sandia Mountains. Overall, detection probability at the activity center (g0) was low across all study areas and ranged from 0.00001 to 0.02. The low values of g0 were primarily a result of half of all hair samples for which genotypes were attempted failing to produce a complete genotype. We speculate that the low success we had genotyping hair samples was due to exceedingly high levels of ultraviolet (UV) radiation that degraded the DNA in the hair. Despite sampling difficulties, we were able to produce density estimates with levels of precision comparable to those estimated for black bears elsewhere in the United States.

  4. The stable problem of the black-hole connected region in the Schwarzschild black hole

    OpenAIRE

    Tian, Guihua

    2005-01-01

    The stability of the Schwarzschild black hole is studied. Using the Painlev\\'{e} coordinate, our region can be defined as the black-hole-connected region(r>2m, see text) of the Schwarzschild black hole or the white-hole-connected region(r>2m, see text) of the Schwarzschild black hole. We study the stable problems of the black-hole-connected region. The conclusions are: (1) in the black-hole-connected region, the initially regular perturbation fields must have real frequency or complex frequen...

  5. "Having Our Say": High Achieving African American Male College Graduates Speak about Parental Involvement and Parenting Style

    Science.gov (United States)

    Odom, Lynn Lanier; McNeese, Rose M.

    2014-01-01

    The purpose of this study was to examine the patterns of parental involvement and parenting styles of the parents of academically successful African American males who graduated from historically Black colleges or universities (Odom, 2013). More specifically, the study investigated relationships among students' perceptions of their parents'…

  6. Non-invasive measurement of thyroid hormone in feces of a diverse array of avian and mammalian species.

    Science.gov (United States)

    Wasser, Samuel K; Azkarate, Jurgi Cristòbal; Booth, Rebecca K; Hayward, Lisa; Hunt, Kathleen; Ayres, Katherine; Vynne, Carly; Gobush, Kathleen; Canales-Espinosa, Domingo; Rodríguez-Luna, Ernesto

    2010-08-01

    We developed and validated a non-invasive thyroid hormone measure in feces of a diverse array of birds and mammals. An I(131) radiolabel ingestion study in domestic dogs coupled with High Pressure Liquid Chromatography (HPLC) analysis, showed that peak excretion in feces occurred at 24-48h post-ingestion, with I(131)-labelled thyroid hormone metabolites excreted primarily as triiodothyronine (T3) and relatively little thyroxine (T4), at all excretion times examined. The immunoreactive T3 profile across these same HPLC fractions closely corresponded with the I(131) radioactive profile. By contrast, the T4 immunoreactive profile was disproportionately high, suggesting that T4 excretion included a high percentage of T4 stores. We optimized and validated T3 and T4 extraction and assay methods in feces of wild northern spotted owls, African elephants, howler monkeys, caribou, moose, wolf, maned wolf, killer whales and Steller sea lions. We explained 99% of the variance in high and low T3 concentrations derived from species-specific sample pools, after controlling for species and the various extraction methods tested. Fecal T3 reflected nutritional deficits in two male and three female howler monkeys held in captivity for translocation from a highly degraded habitat. Results suggest that thyroid hormone can be accurately and reliably measured in feces, providing important indices for environmental physiology across a diverse array of birds and mammals. Copyright 2010 Elsevier Inc. All rights reserved.

  7. Quantum aspects of black holes

    CERN Document Server

    2015-01-01

    Beginning with an overview of the theory of black holes by the editor, this book presents a collection of ten chapters by leading physicists dealing with the variety of quantum mechanical and quantum gravitational effects pertinent to black holes. The contributions address topics such as Hawking radiation, the thermodynamics of black holes, the information paradox and firewalls, Monsters, primordial black holes, self-gravitating Bose-Einstein condensates, the formation of small black holes in high energetic collisions of particles, minimal length effects in black holes and small black holes at the Large Hadron Collider. Viewed as a whole the collection provides stimulating reading for researchers and graduate students seeking a summary of the quantum features of black holes.

  8. Traditional male circumcision-related fatalities in the Mthatha area of South Africa.

    Science.gov (United States)

    Meel, B L

    2010-10-01

    Traditional male circumcision is still widely practised by the Xhosa population throughout South Africa. Male circumcision is carried out mainly during summer and winter seasons. This is a retrospective record review of the male circumcision-related fatalities at Mthatha General Hospital during 2005 and 2006. The purpose of this study is to highlight the problem of circumcision-related deaths in the Mthatha area of South Africa. Twenty-five deaths related to traditional circumcisions were recorded over the period. The common causes of deaths were septicaemia (9 patients; 36%), pneumonia (5; 20%), dehydration (3; 12%), assault (3; 12%), thromboembolism (2; 8%), gangrene (2; 8%) and congestive heart failure (1; 4%). All fatalities were among black Africans with a median age of 17.56 (SD = 2.56) years. In seven deaths (28%) the young men came from the Libode District. The youngest victim was 12 years old. Most of the deaths (13; 52%) occurred in July 2006. The mortality associated with traditional male circumcision in the Mthatha area of South Africa is alarming.

  9. Black holes and beyond

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-02-01

    Belief in the existence of black holes is the ultimate act of faith for a physicist. First suggested by the English clergyman John Michell in the year 1784, the gravitational pull of a black hole is so strong that nothing - not even light - can escape. Gravity might be the weakest of the fundamental forces but black-hole physics is not for the faint-hearted. Black holes present obvious problems for would-be observers because they cannot, by definition, be seen with conventional telescopes - although before the end of the decade gravitational-wave detectors should be able to study collisions between black holes. Until then astronomers can only infer the existence of a black hole from its gravitational influence on other matter, or from the X-rays emitted by gas and dust as they are dragged into the black hole. However, once this material passes through the 'event horizon' that surrounds the black hole, we will never see it again - not even with X-ray specs. Despite these observational problems, most physicists and astronomers believe that black holes do exist. Small black holes a few kilometres across are thought to form when stars weighing more than about two solar masses collapse under the weight of their own gravity, while supermassive black holes weighing millions of solar masses appear to be present at the centre of most galaxies. Moreover, some brave physicists have proposed ways to make black holes - or at least event horizons - in the laboratory. The basic idea behind these 'artificial black holes' is not to compress a large amount of mass into a small volume, but to reduce the speed of light in a moving medium to less than the speed of the medium and so create an event horizon. The parallels with real black holes are not exact but the experiments could shed new light on a variety of phenomena. The first challenge, however, is to get money for the research. One year on from a high-profile meeting on artificial black holes in London, for

  10. Complicated Contradictions Amid Black Feminism and Millennial Black Women Teachers Creating Curriculum for Black Girls

    Science.gov (United States)

    Nyachae, Tiffany M.

    2016-01-01

    Millennial Black women teachers wrestle with two simultaneous burdens: disrupting the racist and sexist status quo of schooling through curriculum, and employing tactics to survive school politics among their majority White women colleagues. This article describes how the "Sisters of Promise" (SOP) curriculum aligned with Black feminism…

  11. Food use and nutrition of black ducks nesting in Maine

    Science.gov (United States)

    Reinecke, K.J.; Owen, R.B.

    1980-01-01

    Based on 32 adult black ducks (Anas rubripes) collected during the nesting seasons of 1974-76, the proportion of macro invertebrates (as aggregate [average] percent of dry weight) in the diet of males, egg-laying females, and postlaying females was 60, 75, and 55%, respectivey. Sample sizes were small, and the differences associated with sex and reproductive condition were not signficant. Molluscs, Isopods, ephemeropteran and odonate nymphs, and coleopteran, trichopteran, and dipteran larvae contributed 74% of the dry weight and 64% of the gross energy ingested. Data from proximate analyses of 9 invertebrate and 9 plant foods were combined with food habits data to estimate the nutrients available to breeding hens. We concluded that females with access to an adequate amount of natural food including invertebrates and the seeds and tubers of aquatic plants would obtain sufficient minerals, protein, and energy for reproduction. Food quality does not appear to limit the density of black ducks nesting in Maine.

  12. Rotating black holes at future colliders. III. Determination of black hole evolution

    International Nuclear Information System (INIS)

    Ida, Daisuke; Oda, Kin-ya; Park, Seong Chan

    2006-01-01

    TeV scale gravity scenario predicts that the black hole production dominates over all other interactions above the scale and that the Large Hadron Collider will be a black hole factory. Such higher-dimensional black holes mainly decay into the standard model fields via the Hawking radiation whose spectrum can be computed from the greybody factor. Here we complete the series of our work by showing the greybody factors and the resultant spectra for the brane-localized spinor and vector field emissions for arbitrary frequencies. Combining these results with the previous works, we determine the complete radiation spectra and the subsequent time evolution of the black hole. We find that, for a typical event, well more than half a black hole mass is emitted when the hole is still highly rotating, confirming our previous claim that it is important to take into account the angular momentum of black holes

  13. BlackBerry For Dummies

    CERN Document Server

    Kao, Robert

    2010-01-01

    Get the most juice out of your BlackBerry handheld!. Feature-rich and complex, the BlackBerry is the number one smartphone in the corporate world is among the most popular handhelds for business users. This new and updated edition includes all the latest and greatest information on new and current BlackBerry mobile devices. Covering a range of valuable how-to topics, this helpful guide explores the BlackBerry's most useful features, techniques for getting the most out of your BlackBerry, and practical information about power usage.: Covers all aspects of the number one smartphone in the corpor

  14. Black Hole Area Quantization rule from Black Hole Mass Fluctuations

    OpenAIRE

    Schiffer, Marcelo

    2016-01-01

    We calculate the black hole mass distribution function that follows from the random emission of quanta by Hawking radiation and with this function we calculate the black hole mass fluctuation. From a complete different perspective we regard the black hole as quantum mechanical system with a quantized event horizon area and transition probabilities among the various energy levels and then calculate the mass dispersion. It turns out that there is a perfect agreement between the statistical and ...

  15. The role of cognitive style in the stress and coping of black South African adolescents.

    Science.gov (United States)

    van Rooyen, Melinda; Naude, Luzelle; Nel, Lindi; Esterhuyse, Karel

    2014-12-01

    Although stress is a common phenomenon in all phases of life, it can be said that adolescence is a particularly stressful life stage. In South Africa, black adolescents are faced with many stressors and challenges which are placing demands on their emotional and cognitive resources. The aim of this study was to determine whether black South African adolescents with different cognitive styles (i.e. rational or experiential) differ in their levels of stress and coping. Furthermore, the common stressors that black adolescents experience and the coping styles predominantly used by black adolescents could be determined. One hundred and eighty-seven participants (88 males and 99 females) completed the Rational Experiential, the Coping Reponses and the Adolescent Stress Inventory. Adolescents operating from an experiential cognitive style experienced more stress regarding school performance, school attendance, financial pressure and emerging adult responsibility than adolescents operating from a rational cognitive style. Adolescents employing a rational style sought more alternative rewards as a coping strategy, whereas adolescents employing an experiential style relied more on emotional discharge. The findings of this study concur with previous research, but provide a unique perspective on adolescents' stress and coping in this South African context.

  16. Framing black boys: parent, teacher, and student narratives of the academic lives of black boys.

    Science.gov (United States)

    Rowley, Stephanie J; Ross, Latisha; Lozada, Fantasy T; Williams, Amber; Gale, Adrian; Kurtz-Costes, Beth

    2014-01-01

    The discourse on Black boys tends to suggest that Black boys are in complete peril. We begin with evidence that Black boys are excelling in certain contexts (i.e., in certain states, in certain schools, and in certain courses). We then discuss the ways in which the narratives used by parents, teachers, and Black boys themselves may serve to further reinforce views that Black boys are beyond hope. Research on Black parents suggests that they tend to view their sons as vulnerable and have lower expectations for sons than for daughters. Studies of teachers show that they tend to view Black boys as unteachable, as social problems, and as scary. Research on Black boys shows that they are sometimes complicit in supporting these narratives by engaging in negative or ste reotypical behavior. We also include recent research that includes counter-narratives of Black boys. We end with suggestions for future research.

  17. The Black Family as Educator.

    Science.gov (United States)

    Wallace, Joan

    The black family is the primary socializing agent of the black child and, thus, the primary educator. The culture of blacks in America, in which the child is steeped, is unique, complex and rich-the result of a convergence and fusion of African, American, and European influences. In its education of the black child, the black family must deal,…

  18. Monopole Black Hole Skyrmions

    OpenAIRE

    Moss, Ian G; Shiiki, N; Winstanley, E

    2000-01-01

    Charged black hole solutions with pion hair are discussed. These can be\\ud used to study monopole black hole catalysis of proton decay.\\ud There also exist\\ud multi-black hole skyrmion solutions with BPS monopole behaviour.

  19. Skyrmion black hole hair: Conservation of baryon number by black holes and observable manifestations

    Energy Technology Data Exchange (ETDEWEB)

    Dvali, Gia [Arnold Sommerfeld Center, Ludwig-Maximilians-Universität, 80333 München (Germany); Max-Planck-Institut für Physik, Werner-Heisenberg-Institut, 80805 München (Germany); Center for Cosmology and Particle Physics, Department of Physics, New York University, 4 Washington Place, New York, NY 10003 (United States); Gußmann, Alexander, E-mail: alexander.gussmann@physik.uni-muenchen.de [Arnold Sommerfeld Center, Ludwig-Maximilians-Universität, 80333 München (Germany)

    2016-12-15

    We show that the existence of black holes with classical skyrmion hair invalidates standard proofs that global charges, such as the baryon number, cannot be conserved by a black hole. By carefully analyzing the standard arguments based on a Gedankenexperiment in which a black hole is seemingly-unable to return the baryon number that it swallowed, we identify inconsistencies in this reasoning, which does not take into the account neither the existence of skyrmion black holes nor the baryon/skyrmion correspondence. We then perform a refined Gedankenexperiment by incorporating the new knowledge and show that no contradiction with conservation of baryon number takes place at any stage of black hole evolution. Our analysis also indicates no conflict between semi-classical black holes and the existence of baryonic gauge interaction arbitrarily-weaker than gravity. Next, we study classical cross sections of a minimally-coupled massless probe scalar field scattered by a skyrmion black hole. We investigate how the skyrmion hair manifests itself by comparing this cross section with the analogous cross section caused by a Schwarzschild black hole which has the same ADM mass as the skyrmion black hole. Here we find an order-one difference in the positions of the characteristic peaks in the cross sections. The peaks are shifted to smaller scattering angles when the skyrmion hair is present. This comes from the fact that the skyrmion hair changes the near horizon geometry of the black hole when compared to a Schwarzschild black hole with same ADM mass. We keep the study of this second aspect general so that the qualitative results which we obtain can also be applied to black holes with classical hair of different kind.

  20. Application of large-scale parentage analysis for investigating natal dispersal in highly vagile vertebrates: a case study of American black bears (Ursus americanus).

    Science.gov (United States)

    Moore, Jennifer A; Draheim, Hope M; Etter, Dwayne; Winterstein, Scott; Scribner, Kim T

    2014-01-01

    Understanding the factors that affect dispersal is a fundamental question in ecology and conservation biology, particularly as populations are faced with increasing anthropogenic impacts. Here we collected georeferenced genetic samples (n = 2,540) from three generations of black bears (Ursus americanus) harvested in a large (47,739 km2), geographically isolated population and used parentage analysis to identify mother-offspring dyads (n = 337). We quantified the effects of sex, age, habitat type and suitability, and local harvest density at the natal and settlement sites on the probability of natal dispersal, and on dispersal distances. Dispersal was male-biased (76% of males dispersed) but a small proportion (21%) of females also dispersed, and female dispersal distances (mean ± SE  =  48.9±7.7 km) were comparable to male dispersal distances (59.0±3.2 km). Dispersal probabilities and dispersal distances were greatest for bears in areas with high habitat suitability and low harvest density. The inverse relationship between dispersal and harvest density in black bears suggests that 1) intensive harvest promotes restricted dispersal, or 2) high black bear population density decreases the propensity to disperse. Multigenerational genetic data collected over large landscape scales can be a powerful means of characterizing dispersal patterns and causal associations with demographic and landscape features in wild populations of elusive and wide-ranging species.

  1. Application of large-scale parentage analysis for investigating natal dispersal in highly vagile vertebrates: a case study of American black bears (Ursus americanus.

    Directory of Open Access Journals (Sweden)

    Jennifer A Moore

    Full Text Available Understanding the factors that affect dispersal is a fundamental question in ecology and conservation biology, particularly as populations are faced with increasing anthropogenic impacts. Here we collected georeferenced genetic samples (n = 2,540 from three generations of black bears (Ursus americanus harvested in a large (47,739 km2, geographically isolated population and used parentage analysis to identify mother-offspring dyads (n = 337. We quantified the effects of sex, age, habitat type and suitability, and local harvest density at the natal and settlement sites on the probability of natal dispersal, and on dispersal distances. Dispersal was male-biased (76% of males dispersed but a small proportion (21% of females also dispersed, and female dispersal distances (mean ± SE  =  48.9±7.7 km were comparable to male dispersal distances (59.0±3.2 km. Dispersal probabilities and dispersal distances were greatest for bears in areas with high habitat suitability and low harvest density. The inverse relationship between dispersal and harvest density in black bears suggests that 1 intensive harvest promotes restricted dispersal, or 2 high black bear population density decreases the propensity to disperse. Multigenerational genetic data collected over large landscape scales can be a powerful means of characterizing dispersal patterns and causal associations with demographic and landscape features in wild populations of elusive and wide-ranging species.

  2. Dating violence among male and female youth seeking emergency department care.

    Science.gov (United States)

    Singh, Vijay; Walton, Maureen A; Whiteside, Lauren K; Stoddard, Sarah; Epstein-Ngo, Quyen; Chermack, Stephen T; Cunningham, Rebecca M

    2014-10-01

    We determine prevalence and correlates of dating violence, dating victimization, and dating aggression among male and female patients aged 14 to 20 years seeking emergency department (ED) care. This was a systematic sampling of subjects aged 14 to 20 years seeking care at a single large academic ED between September 2010 and March 2013. Participants completed a computerized, self-administered, cross-sectional survey of demographics, dating violence from physical abuse measures of the Conflict in Adolescent Dating Relationships Inventory, associated behaviors, and ED health service use. Separate analyses were conducted for male and female patients. Four thousand three hundred eighty-nine youths (86.1% participation rate) were screened, and 4,089 (mean age 17.5 years; 58% female patients) were eligible for analysis. Almost 1 in 5 female patients (n=215; 18.4%) and 1 in 8 male patients (n=212; 12.5%) reported past-year dating violence. Of female patients, 10.6% reported dating victimization and 14.6% dating aggression, whereas of male patients, 11.7% reported dating victimization and 4.9% reported dating aggression. Multivariate analyses showed that variables associated with any male dating violence were black race (adjusted odds ratio [AOR] 2.26; 95% CI 1.54 to 3.32), alcohol misuse (AOR 1.03; 95% CI 1.00 to 1.06), illicit drug use (AOR 2.38; 95% CI 1.68 to 3.38), and depression (AOR 2.13; 95% CI 1.46 to 3.10); any female dating violence was associated with black race (AOR 1.68; 95% CI 1.25 to 2.25), public assistance (AOR 1.64; 95% CI 1.28 to 2.09), grades D and below (AOR 1.62; 95% CI 1.07 to 2.43), alcohol misuse (AOR 1.04; 95% CI 1.02 to 1.07), illicit drug use (AOR 2.85; 95% CI 2.22 to 3.66), depression (AOR 1.86; 95% CI 1.42 to 2.44), and any past year ED visit for intentional injury (AOR 2.64; 95% CI 1.30 to 5.40). Nearly 1 of 6 male and female patients aged 14 to 20 years and seeking ED care report recent dating violence, and health disparities remain among

  3. Statistical black-hole thermodynamics

    International Nuclear Information System (INIS)

    Bekenstein, J.D.

    1975-01-01

    Traditional methods from statistical thermodynamics, with appropriate modifications, are used to study several problems in black-hole thermodynamics. Jaynes's maximum-uncertainty method for computing probabilities is used to show that the earlier-formulated generalized second law is respected in statistically averaged form in the process of spontaneous radiation by a Kerr black hole discovered by Hawking, and also in the case of a Schwarzschild hole immersed in a bath of black-body radiation, however cold. The generalized second law is used to motivate a maximum-entropy principle for determining the equilibrium probability distribution for a system containing a black hole. As an application we derive the distribution for the radiation in equilibrium with a Kerr hole (it is found to agree with what would be expected from Hawking's results) and the form of the associated distribution among Kerr black-hole solution states of definite mass. The same results are shown to follow from a statistical interpretation of the concept of black-hole entropy as the natural logarithm of the number of possible interior configurations that are compatible with the given exterior black-hole state. We also formulate a Jaynes-type maximum-uncertainty principle for black holes, and apply it to obtain the probability distribution among Kerr solution states for an isolated radiating Kerr hole

  4. Differences in Current Cigarette Smoking Between Non-Hispanic Whites and Non-Hispanic Blacks by Gender and Age Group, United States, 2001 – 2013

    Science.gov (United States)

    Caraballo, Ralph S.; Sharapova, Saida; Asman, Katherine J.

    2015-01-01

    Introduction For years, national U.S. surveys have consistently found a lower cigarette smoking prevalence among non-Hispanic (NH) black adolescents and young adults than their NH white counterpart while finding either similar or higher smoking prevalence in NH blacks among older adults. Because these surveys do not collect biomarker information to validate smoking self-reports, we also present results from the National Health and Nutrition Examination Survey (NHANES), which collects cotinine (a nicotine biomarker) to determine if U.S. surveys consistently show racial differences in smoking prevalence. Methods We present NH black and NH white current smoking estimates in the Youth Risk Behavior Survey (2001–2013), National Youth Tobacco Survey (2004–2012), National Survey on Drug Use and Health (2002–2012), National Health Interview Survey (2001–2013), and NHANES (2001–2012). Results Using cotinine by itself or with self-reports to compare smoking prevalence between NH black and NH white males aged 12 – 25 years, no difference in current smoking was found. For male adult ≥26 years, all surveys consistently found a higher smoking prevalence among NH blacks. For females aged 12 – 25 years, all surveys found a higher smoking prevalence among NH whites. While inconsistent results across surveys were found for those aged ≥26 years, cotinine results showed a higher smoking prevalence among NH black females. Conclusion Some racial differences in self-reported smoking are not confirmed when supplemented with serum cotinine to detect current cigarette smokers. Improving the measurement of current smoking is important to accurately evaluate racial smoking differences. PMID:26980863

  5. Black holes without firewalls

    Science.gov (United States)

    Larjo, Klaus; Lowe, David A.; Thorlacius, Larus

    2013-05-01

    The postulates of black hole complementarity do not imply a firewall for infalling observers at a black hole horizon. The dynamics of the stretched horizon, that scrambles and reemits information, determines whether infalling observers experience anything out of the ordinary when entering a large black hole. In particular, there is no firewall if the stretched horizon degrees of freedom retain information for a time of the order of the black hole scrambling time.

  6. Fear of a Black femme: The existential conundrum of embodying a Black femme identity while being a professor of Black, queer, and feminist studies.

    Science.gov (United States)

    Story, Kaila Adia

    2017-10-02

    Although a Black femme identity has been defined and embodied by many as an identity with Black feminist roots and revolutionary potentials, Black femmes are still rendered hypervisible and invisible through racist and heteronormative politics. Similarly, embodying a Black femme identity as a professor in academia often engenders these same pretenses of hypervisibility and invisibility. This essay explores what this existential conundrum has been for me as both a Black femme and professor of Black queer and feminist studies, while illuminating the mix of forces within academia that have attempted to stifle my chosen sexual identity and gendered performance.

  7. Comparison of telomere length in black and white teachers from South Africa: the sympathetic activity and ambulatory blood pressure in Africans study.

    Science.gov (United States)

    von Känel, Roland; Malan, Nico T; Hamer, Mark; Malan, Leoné

    2015-01-01

    Telomere length is a marker of biological aging that has been linked to cardiovascular disease risk. The black South African population is witnessing a tremendous increase in the prevalence of cardiovascular disease, part of which might be explained through urbanization. We compared telomere length between black South Africans and white South Africans and examined which biological and psychosocial variables played a role in ethnic difference in telomere length. We measured leukocyte telomere length in 161 black South African teachers and 180 white South African teachers aged 23 to 66 years without a history of atherothrombotic vascular disease. Age, sex, years having lived in the area, human immunodeficiency virus (HIV) infection, hypertension, body mass index, dyslipidemia, hemoglobin A1c, C-reactive protein, smoking, physical activity, alcohol abuse, depressive symptoms, psychological distress, and work stress were considered as covariates. Black participants had shorter (median, interquartile range) relative telomere length (0.79, 0.70-0.95) than did white participants (1.06, 0.87-1.21; p < .001), and this difference changed very little after adjusting for covariates. In fully adjusted models, age (p < .001), male sex (p = .011), and HIV positive status (p = .023) were associated with shorter telomere length. Ethnicity did not significantly interact with any covariates in determining telomere length, including psychosocial characteristics. Black South Africans showed markedly shorter telomeres than did white South African counterparts. Age, male sex, and HIV status were associated with shorter telomere length. No interactions between ethnicity and biomedical or psychosocial factors were found. Ethnic difference in telomere length might primarily be explained by genetic factors.

  8. Serosurvey for selected pathogens in free-ranging American black bears (Ursus americanus) in Maryland, USA.

    Science.gov (United States)

    Bronson, Ellen; Spiker, Harry; Driscoll, Cindy P

    2014-10-01

    American black bears (Ursus americanus) in Maryland, USA, live in forested areas in close proximity to humans and their domestic pets. From 1999 to 2011, we collected 84 serum samples from 63 black bears (18 males; 45 females) in five Maryland counties and tested them for exposure to infectious, including zoonotic, pathogens. A large portion of the bears had antibody to canine distemper virus and Toxoplasma gondii, many at high titers. Prevalences of antibodies to zoonotic agents such as rabies virus and to infectious agents of carnivores including canine adenovirus and canine parvovirus were lower. Bears also had antibodies to vector-borne pathogens common to bears and humans such as West Nile virus, Borrelia burgdorferi, Rickettsia rickettsii, and Anaplasma phagocytophilum. Antibodies were detected to Leptospira interrogans serovars Pomona, Icterohaemorrhagiae, Canicola, Grippotyphosa, and Bratislava. We did not detect antibodies to Brucella canis or Ehrlichia canis. Although this population of Maryland black bears demonstrated exposure to multiple pathogens of concern for humans and domesticated animals, the low levels of clinical disease in this and other free-ranging black bear populations indicate the black bear is likely a spillover host for the majority of pathogens studied. Nevertheless, bear populations living at the human-domestic-wildlife interface with increasing human and domestic animal exposure should continue to be monitored because this population likely serves as a useful sentinel of ecosystem health.

  9. Black Lives Matter of Black Identity Extremist? : The FBI, Black Activists and the Struggle for Victimhood

    NARCIS (Netherlands)

    Mutsaers, Paul

    2017-01-01

    The question 'who is the victim?' is an important social directive that shapes the struggles for victimhood in which Black Lives Matters, U.S. police forces and their various (counter)publics are currently engaging. This column begins with a controversial FBI report on so-called Black Identity

  10. Einstein-Gauss-Bonnet metrics: black holes, black strings and a staticity theorem

    International Nuclear Information System (INIS)

    Bogdanos, C.; Charmousis, C.; Gouteraux, B.; Zegers, R.

    2009-01-01

    We find the general solution of the 6-dimensional Einstein-Gauss-Bonnet equations in a large class of space and time-dependent warped geometries. Several distinct families of solutions are found, some of which include black string metrics, space and time-dependent solutions and black holes with exotic horizons. Among these, some are shown to verify a Birkhoff type staticity theorem, although here, the usual assumption of maximal symmetry on the horizon is relaxed, allowing exotic horizon geometries. We provide explicit examples of such static exotic black holes, including ones whose horizon geometry is that of a Bergman space. We find that the situation is very different from higher-dimensional general relativity, where Einstein spaces are admissible black hole horizons and the associated black hole potential is not even affected. In Einstein-Gauss-Bonnet theory, on the contrary, the non-trivial Weyl tensor of such exotic horizons is exposed to the bulk dynamics through the higher order Gauss-Bonnet term, severely constraining the allowed horizon geometries and adding a novel charge-like parameter to the black hole potential. The latter is related to the Euler characteristic of the four-dimensional horizon and provides, in some cases, additional black hole horizons.

  11. Accreting Black Holes

    OpenAIRE

    Begelman, Mitchell C.

    2014-01-01

    I outline the theory of accretion onto black holes, and its application to observed phenomena such as X-ray binaries, active galactic nuclei, tidal disruption events, and gamma-ray bursts. The dynamics as well as radiative signatures of black hole accretion depend on interactions between the relatively simple black-hole spacetime and complex radiation, plasma and magnetohydrodynamical processes in the surrounding gas. I will show how transient accretion processes could provide clues to these ...

  12. Naked black holes

    International Nuclear Information System (INIS)

    Horowitz, G.T.; Ross, S.F.

    1997-01-01

    It is shown that there are large static black holes for which all curvature invariants are small near the event horizon, yet any object which falls in experiences enormous tidal forces outside the horizon. These black holes are charged and near extremality, and exist in a wide class of theories including string theory. The implications for cosmic censorship and the black hole information puzzle are discussed. copyright 1997 The American Physical Society

  13. Stereotype or success? Prime-time television's portrayals of gay male, lesbian, and bisexual characters.

    Science.gov (United States)

    Raley, Amber B; Lucas, Jennifer L

    2006-01-01

    The current content analysis of prime-time network television during the fall of 2001 seeks to identify the representation of Gay male, Lesbian, and Bisexual characters in shows known to have one reoccurring homosexual character based on the theories of Clark and Berry. Clark (1969) established four stages of media representation for minority groups: non-representation, ridicule, regulation, and respect. The findings of the study support the premise that Gay males and Lesbians have passed Clark's stage of non-representation and have progressed into the stage of ridicule and some are moving into the stages of regulation and respect. Berry (1980) devised three periods based on the television portrayal of Blacks: The Stereotypic Age, The New Awareness, and Stabilization. Results were mixed, with only a partial support of the hypothesis that Gay males and Lesbians had advanced beyond The Stereotypic Age.

  14. Legitimizing Blacks in Philosophy

    Directory of Open Access Journals (Sweden)

    Jameliah Shorter-Bourhanou

    2017-12-01

    Full Text Available In its efforts toward improving diversity, the discipline of philosophy has tended to focus on increasing the number of black philosophers. One crucial issue that has received less attention is the extent to which black philosophers are delegitimized in the discipline because their philosophical contributions challenge the status quo. A systematic problem that bars black philosophers from equal and full participation, this delegitimization precludes the emergence of genuine diversity and reveals the importance of interrogating broader attitudes toward black philosophical contributions. In this essay, I argue for radical systematic changes to disciplinary hallmarks of professionalization such as pedagogy, mentoring, publishing, and hiring practices with the aim of legitimizing black philosophers and their contributions.

  15. LITERATURA DE AUTORIA FEMININA NEGRA: (DESSILENCIAMENTOS E RESSIGNIFICAÇÕES (LITERATURE OF BLACK FEMINE AUTHORSHIP: (DESILENCE AND NEW MEANINGS

    Directory of Open Access Journals (Sweden)

    Ana Rita Santiago da Silva

    2010-06-01

    Full Text Available It is difficult to find in Brazilian literature works in which discursive constructions and narratives of women appear figured by male power. Prevail in them, for example, preachings of black female characters overwhelmed not only by patriarchy, as well as representations surrounded by traces of inferiority, virility and strong negative valuation of their ethnic and cultural diversity. When you add the fact that the invisibility of black women's writing, the scene of literary tradition, we can more easily understand the literature you want distinctive, innovative and transgressive, produced by them. Thus, this text will make an interpretative reading practices (un silencing of literary authorship and literary voices of black women writers, who, as discursive formations, march away from stigmas and deletions and coming brands of otherness.

  16. Black holes are hot

    International Nuclear Information System (INIS)

    Gibbons, G.

    1976-01-01

    Recent work, which has been investigating the use of the concept of entropy with respect to gravitating systems, black holes and the universe as a whole, is discussed. The resulting theory of black holes assigns a finite temperature to them -about 10 -7 K for ordinary black holes of stellar mass -which is in complete agreement with thermodynamical concepts. It is also shown that black holes must continuously emit particles just like ordinary bodies which have a certain temperature. (U.K.)

  17. Urban Preparation: Young Black Men Moving from Chicago's South Side to Success in Higher Education

    Science.gov (United States)

    Warren, Chezare A.

    2017-01-01

    Chezare A. Warren chronicles the transition of a cohort of young Black males from Urban Prep Charter Academy for Young Men to their early experiences in higher education. A rich and closely observed account of a mission-driven school and its students, "Urban Preparation" makes a significant contribution to our understanding of how young…

  18. Intermediate-Mass Black Holes

    Science.gov (United States)

    Miller, M. Coleman; Colbert, E. J. M.

    2004-01-01

    The mathematical simplicity of black holes, combined with their links to some of the most energetic events in the universe, means that black holes are key objects for fundamental physics and astrophysics. Until recently, it was generally believed that black holes in nature appear in two broad mass ranges: stellar-mass (M~3 20 M⊙), which are produced by the core collapse of massive stars, and supermassive (M~106 1010 M⊙), which are found in the centers of galaxies and are produced by a still uncertain combination of processes. In the last few years, however, evidence has accumulated for an intermediate-mass class of black holes, with M~102 104 M⊙. If such objects exist they have important implications for the dynamics of stellar clusters, the formation of supermassive black holes, and the production and detection of gravitational waves. We review the evidence for intermediate-mass black holes and discuss future observational and theoretical work that will help clarify numerous outstanding questions about these objects.

  19. The Effect of Black Peers on Black Test Scores

    Science.gov (United States)

    Armor, David J.; Duck, Stephanie

    2007-01-01

    Recent studies have used increasingly complex methodologies to estimate the effect of peer characteristics--race, poverty, and ability--on student achievement. A paper by Hanushek, Kain, and Rivkin using Texas state testing data has received particularly wide attention because it found a large negative effect of school percent black on black math…

  20. Black hole multiplicity at particle colliders (Do black holes radiate mainly on the brane?)

    International Nuclear Information System (INIS)

    Cavaglia, Marco

    2003-01-01

    If gravity becomes strong at the TeV scale, we may have the chance to produce black holes at particle colliders. In this Letter we revisit some phenomenological signatures of black hole production in TeV-gravity theories. We show that the bulk-to-brane ratio of black hole energy loss during the Hawking evaporation phase depends crucially on the black hole greybody factors and on the particle degrees of freedom. Since the greybody factors have not yet been calculated in the literature, and the particle content at trans-Planckian energies is not known, it is premature to claim that the black hole emits mainly on the brane. We also revisit the decay time and the multiplicity of the decay products of black hole evaporation. We give general formulae for black hole decay time and multiplicity. We find that the number of particles produced during the evaporation phase may be significantly lower than the average multiplicity which has been used in the past literature

  1. Protective Factors as an Explanation for the "Paradox" of Black-White Differences in Heavy Drinking.

    Science.gov (United States)

    Mulia, Nina; Ye, Yu; Karriker-Jaffe, Katherine J; Zemore, Sarah E; Jones-Webb, Rhonda

    2018-04-02

    African Americans are generally known to have lower heavy drinking prevalence than Whites despite often greater individual and community risk factors. While it is supposed that their protective resources explain this "paradox," studies have not explicitly examined this. Assess the contribution of protective resources to Black-White differences in heavy drinking, and (secondarily) whether protective resources operate by reducing heavy drinking and/or increasing abstinence. Using data from the 2009-2010 U.S. National Alcohol Survey (N = 3,133 Whites and 1,040 Blacks ages 18+), we applied propensity score (PS) weighting to estimate racial differences in heavy drinking and abstinence under hypothetical conditions in which Whites are similar to Blacks in: (1) age and marital status; (2) socioeconomic position and unfair treatment; (3) neighborhood socioeconomic conditions and alcohol outlet density; and (4) protective resources (proscriptive religiosity, area-level religiosity, "drier" network drinking norms and patterns, and family social support). The Black-White gap in male and female drinkers' baseline heavy drinking increased after weighting adjustments for demographics. In women, this gap was reduced after weighting on disadvantage and eliminated after adjusting for protective resources. In men, adjustment for disadvantage increased the racial gap, and protective resources reduced it. Protective resources had a stronger effect on Black-White differences in men's abstinence than heavy drinking, but similar effects on these outcomes in women. Protective resources help explain Black-White differences in men's and particularly women's heavy drinking. Future research is needed to elucidate mechanisms of action and additional factors underlying racial differences in men's heavy drinking.

  2. Understanding the Black Aesthetic Experience.

    Science.gov (United States)

    Curtis, Marvin V.

    1988-01-01

    Discussing the importance of the Black aesthetic experience, Curtis examines Black cultural heritage and participatory style, the spiritual, and the creation and recreation of Black music. Advocating multicultural music education in teacher training, he suggests that Black music be studied for its value and contribution to society. Lists five ways…

  3. Black Writers' Views of America.

    Science.gov (United States)

    Hairston, Loyle

    1979-01-01

    This article argues that the stagnation, pessimism, and self-pity evident in recent Black writing results in part from the alienation of Black writers from the mainstream of Black life, and in part from the illusions that they share with other Blacks who have embraced the American value system. (Author/EB)

  4. Fixing Systems, Not Kids: Changing the Narrative of Black Males in Guilford County Schools

    Science.gov (United States)

    Brinkley, Barry; Hines, Eric; Jones, Akisha; McMillian, Effie G.; Sturdivant, Brooksie; Walker, Monica

    2018-01-01

    Considerable research on African American males (AAMs) in American schools over the past ten years shows that they are underrepresented in every positive measure of educational outcomes, and overrepresented in every negative measure. Many educators have developed low expectations, deficit thinking, and implicit biases toward AAMs and their…

  5. String-Corrected Black Holes

    Energy Technology Data Exchange (ETDEWEB)

    Hubeny, V.

    2005-01-12

    We investigate the geometry of four dimensional black hole solutions in the presence of stringy higher curvature corrections to the low energy effective action. For certain supersymmetric two charge black holes these corrections drastically alter the causal structure of the solution, converting seemingly pathological null singularities into timelike singularities hidden behind a finite area horizon. We establish, analytically and numerically, that the string-corrected two-charge black hole metric has the same Penrose diagram as the extremal four-charge black hole. The higher derivative terms lead to another dramatic effect--the gravitational force exerted by a black hole on an inertial observer is no longer purely attractive. The magnitude of this effect is related to the size of the compactification manifold.

  6. Space and habitat use by black bears in the Elwha valley prior to dam removal

    Science.gov (United States)

    Sager-Fradkin, K.A.; Jenkins, K.J.; Happe, P.J.; Beecham, J.J.; Wright, R.G.; Hoffman, R.A.

    2008-01-01

    Dam removal and subsequent restoration of salmon to the Elwha River is expected to cause a shift in nutrient dynamics within the watershed. To document how this influx of nutrients and energy may affect black bear (Ursus americanus) ecology, we used radio-telemetry to record movements of 11 male and two female black bears in the Elwha Valley from 2002-06. Our objective was to collect baseline data on bear movements prior to dam removal. We calculated annual home ranges, described seasonal timing of den entry and emergence, and described seasonal patterns of distribution and habitat use. Adaptive kernel home ranges were larger formales (mean = 151.1 km2, SE = 21.4) than females (mean = 38.8 km2, SE = 13.0). Males ranged widely and frequently left the watershed during late summer. Further, they exhibited predictable and synchronous patterns of elevation change throughout each year. Bears entered their winter dens between 8 October and 15 December and emerged from dens between 10 March and 9 May. Male bears used low-elevation conifer and hardwood forests along the Elwha floodplain during spring, mid- to high-elevation forests and meadows during early summer, high-elevation forests, meadows and shrubs during late summer, and mid-elevation forests, shrubs and meadows during fall. Data acquired during this study provide important baseline information for comparison after dam removal, when bears may alter their late summer and fall movement and denning patterns to take advantage of energy-rich spawning salmon.

  7. Switching to instant black coffee modulates sodium selenite-induced cataract in rats

    Directory of Open Access Journals (Sweden)

    El Okda, E. A.

    2016-04-01

    Full Text Available The influence of daily consumption of some common beverages on the development of cataract in rats was investigated. Total phenol content was determined in the beverages and an oral standardized dose of total phenols from each beverage was given to the treated rats. Weaned male albino rats were used and divided into five groups (n=7. Rats were fed Ain 93G and administered the standardized dose of instant coffee, black tea and hibiscus beverages for 30 days. On day 14 all rats were injected with a single dose of sodium selenite (NaSeO bodyweight, except the control groups NC (negative control, did not receive NaSeO and PC (positive control, was already injected on day 1 of the study. The rats were continued on Ain 93G and the standardized dose for another 16 days. Positive control rats were used. Total phenols were 210, 40, and 44 mg/g dry weight gallic acid equivalent in black coffee, black tea, and hibiscus, respectively. Decreased levels (statistically significant P<0.05 of malondialdehyde, total nitric oxide, Ca-Ae, tumor necrosis factor-α, interleukin-1β, superoxide dismutase, and conversely, increased levels (statistically significant P<0.05 of total protein, reduced glutathione, catalase were found in the lenses of the coffee group compared to PC. There are co-phenol substances in the instant black coffee that promoted coffee to be the most effective beverage.

  8. BlackMax: A black-hole event generator with rotation, recoil, split branes, and brane tension

    International Nuclear Information System (INIS)

    Dai Dechang; Starkman, Glenn; Stojkovic, Dejan; Issever, Cigdem; Tseng, Jeff; Rizvi, Eram

    2008-01-01

    We present a comprehensive black-hole event generator, BlackMax, which simulates the experimental signatures of microscopic and Planckian black-hole production and evolution at the LHC in the context of brane world models with low-scale quantum gravity. The generator is based on phenomenologically realistic models free of serious problems that plague low-scale gravity, thus offering more realistic predictions for hadron-hadron colliders. The generator includes all of the black-hole gray-body factors known to date and incorporates the effects of black-hole rotation, splitting between the fermions, nonzero brane tension, and black-hole recoil due to Hawking radiation (although not all simultaneously). The generator can be interfaced with Herwig and Pythia. The main code can be downloaded from http://www-pnp.physics.ox.ac.uk/~issever/BlackMax/blackmax.html.

  9. Internal structure of black holes

    International Nuclear Information System (INIS)

    Cvetic, Mirjam

    2013-01-01

    Full text: We review recent progress that sheds light on the internal structure of general black holes. We first summarize properties of general multi-charged rotating black holes both in four and five dimensions. We show that the asymptotic boundary conditions of these general asymptotically flat black holes can be modified such that a conformal symmetry emerges. These subtracted geometries preserve the thermodynamic properties of the original black holes and are of the Lifshitz type, thus describing 'a black hole in the asymptotically conical box'. Recent efforts employ solution generating techniques to construct interpolating geometries between the original black hole and their subtracted geometries. Upon lift to one dimension higher, these geometries lift to AdS 3 times a sphere, and thus provide a microscopic interpretation of the black hole entropy in terms of dual two-dimensional conformal field theory. (author)

  10. "We're Still Here . . . We're Not Giving Up": Black and Latino Men's Narratives of Transition to Community College

    Science.gov (United States)

    Bukoski, Beth E.; Hatch, Deryl K.

    2016-01-01

    Objective: This study examines masculinity in a manner commensurate with established feminist frameworks to deconstruct a patriarchal system that ill-serves both men and women. Method: We utilized standpoint theory and narrative analysis to examine longitudinal, qualitative data from first-year Black and Latino males as they transition into…

  11. Black supernovae and black holes in non-local gravity

    Energy Technology Data Exchange (ETDEWEB)

    Bambi, Cosimo [Center for Field Theory and Particle Physics and Department of Physics, Fudan University,200433 Shanghai (China); Theoretical Astrophysics, Eberhard-Karls Universität Tübingen,72076 Tübingen (Germany); Malafarina, Daniele [Department of Physics, Nazarbayev University,010000 Astana (Kazakhstan); Modesto, Leonardo [Center for Field Theory and Particle Physics and Department of Physics, Fudan University,200433 Shanghai (China)

    2016-04-22

    In a previous paper, we studied the interior solution of a collapsing body in a non-local theory of gravity super-renormalizable at the quantum level. We found that the classical singularity is replaced by a bounce, after which the body starts expanding. A black hole, strictly speaking, never forms. The gravitational collapse does not create an event horizon but only an apparent one for a finite time. In this paper, we solve the equations of motion assuming that the exterior solution is static. With such an assumption, we are able to reconstruct the solution in the whole spacetime, namely in both the exterior and interior regions. Now the gravitational collapse creates an event horizon in a finite comoving time, but the central singularity is approached in an infinite time. We argue that these black holes should be unstable, providing a link between the scenarios with and without black holes. Indeed, we find a non catastrophic ghost-instability of the metric in the exterior region. Interestingly, under certain conditions, the lifetime of our black holes exactly scales as the Hawking evaporation time.

  12. Black Sea aerosols

    International Nuclear Information System (INIS)

    Hacisalihoglu, G.; Eliyakut, F.; Anwari, M.A.; Ataman, O.Y.; Balkas, T.I.; Tuncel, G.; Olmez, I.

    1991-01-01

    Shipboard, high volume air particulate samples were collected from the Black Sea atmosphere and analyzed by instrumental neutron activation analysis, atomic absorption spectrophotometry and ion chromatography for about 40 elements and ions. Concentrations of elements in the eastern and western parts of the Black Sea are different at the 95% confidence level, with lower concentrations in the eastern Black Sea. Back-trajectories and concentrations of elements in trajectory groups show that Europe accounts for more than 70% of the anthropogenic elements in the atmosphere. The average sulfate concentration was 7 μg/m 3 , which is comparable with rural sulfate levels in western Europe. Fluxes of elements from the atmosphere to the Black Sea are in good agreement with the results of similar flux calculations for other regions

  13. New Directions for Black Women?

    Science.gov (United States)

    McGuigan, Dorothy, Ed.

    1978-01-01

    This collection of papers deals with various aspects of the black female experience in America. "The Black Woman in Transition" discusses the effects of sexism and racism on black women with particular reference to employment and education; it is noted that black women, in comparison with other groups in society, suffer a proportionately higher…

  14. Black Football Coaches in Their Own Words: A Case Study on the Factors of Underrepresentation in the NCAA

    Science.gov (United States)

    Grissett, Michael

    2017-01-01

    The National Collegiate Athletic Association (NCAA) maintains a prominent role in the athletic tradition of this country, yet researchers agree that some of its member institutions have exhibited bias with respect to race and gender. With respect to Black males in the football bowl subdivision (FBS), the head coach to player ratio is…

  15. Black-spot poison ivy.

    Science.gov (United States)

    Schram, Sarah E; Willey, Andrea; Lee, Peter K; Bohjanen, Kimberly A; Warshaw, Erin M

    2008-01-01

    In black-spot poison ivy dermatitis, a black lacquerlike substance forms on the skin when poison ivy resin is exposed to air. Although the Toxicodendron group of plants is estimated to be the most common cause of allergic contact dermatitis in the United States, black-spot poison ivy dermatitis is relatively rare.

  16. What is black hole?

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. What is black hole? Possible end phase of a star: A star is a massive, luminous ball of plasma having continuous nuclear burning. Star exhausts nuclear fuel →. White Dwarf, Neutron Star, Black Hole. Black hole's gravitational field is so powerful that even ...

  17. Genocide and Black Ecology

    Science.gov (United States)

    Sinnette, Calvin H.

    1972-01-01

    Contends that the survival of black people is in serious jeopardy as is evidenced in contemporary discussions on the worldwide plight of black people, and that an exhaustive study of the problem in its many dimensions is seriously lacking; the moral and ethical issues of genocide require examination from a black perspective. (JW)

  18. Quantum effects in black holes

    International Nuclear Information System (INIS)

    Frolov, V.P.

    1979-01-01

    A strict definition of black holes is presented and some properties with regard to their mass are enumerated. The Hawking quantum effect - the effect of vacuum instability in the black hole gravitational field, as a result of shich the black hole radiates as a heated body is analyzed. It is shown that in order to obtain results on the black hole radiation it is sufficient to predetermine the in-vacuum state at a time moment in the past, when the collapsing body has a large size, and its gravitational field can be neglected. The causes and the place of particle production by the black hole, and also the space-time inside the black hole, are considered

  19. Environmentally enriched male mink gain more copulations than stereotypic, barren-reared competitors.

    Directory of Open Access Journals (Sweden)

    María Díez-León

    Full Text Available Wild carnivores in zoos, conservation breeding centres, and farms commonly live in relatively small, unstimulating enclosures. Under these captive conditions, in a range of species including giant pandas, black-footed ferrets, and European mink, male reproductive abilities are often poor. Such problems have long been hypothesized to be caused by these animals' housing conditions. We show for the first time that rearing under welfare-improving (i.e., highly valued and stress-reducing environmental enrichments enhances male carnivores' copulatory performance: in mate choice competitions, enriched male American mink (Neovison vison mated more often than non-enriched males. We screened for several potential mediators of this effect. First was physiological stress and its impact on reproductive physiology; second, stress-mediated changes in morphology and variables related to immunocompetence that could influence male attractiveness; and third, behavioural changes likely to affect social competence, particularly autistic-like excessive routine and repetition ('perseveration' as is reflected in the stereotypies common in captive animals. Consistent with physiological stress, excreted steroid metabolites revealed that non-enriched males had higher cortisol levels and lower androgen levels than enriched conspecifics. Their os penises (bacula also tended to be less developed. Consistent with reduced attractiveness, non-enriched males were lighter, with comparatively small spleens and a trend to greater fluctuating asymmetry. Consistent with impaired social competence, non-enriched males performed more stereotypic behaviour (e.g., pacing in their home cages. Of all these effects, the only significant predictor of copulation number was stereotypy (a trend suggesting that low bodyweights may also be influential: highly stereotypic males gained the fewest copulations. The neurophysiological changes underlying stereotypy thus handicap males sexually. We

  20. Reconceptualizing successful aging among black women and the relevance of the strong black woman archetype.

    Science.gov (United States)

    Baker, Tamara A; Buchanan, NiCole T; Mingo, Chivon A; Roker, Rosalyn; Brown, Candace S

    2015-02-01

    Although there are multiple pathways to successful aging, little is known of what it means to age successfully among black women. There is a growing body of literature suggesting that black women experience a number of social challenges (sexism and racism) that may present as barriers to aging successfully. Applying aspects of the Strong Black Women ideal, into theoretical concepts of successful aging, may be particularly relevant in understanding which factors impair or promote the ability of black women to age successfully. The Strong Black Women archetype is a culturally salient ideal prescribing that black women render a guise of self-reliance, selflessness, and psychological, emotional, and physical strength. Although this ideal has received considerable attention in the behavioral sciences, it has been largely absent within the gerontology field. Nevertheless, understanding the dynamics of this cultural ideal may enhance our knowledge while developing an appreciation of the black woman's ability to age successfully. Rather than summarize the social, physical, and mental health literature focusing on health outcomes of black women, this conceptual review examines the Strong Black Women archetype and its application to the lived experiences of black women and contributions to current theories of successful aging. Focusing on successful aging exclusively among black women enhances our understanding of this group by considering their identity as women of color while recognizing factors that dictate their ability to age successfully. © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  1. Carbon black vs. black carbon and other airborne materials containing elemental carbon: Physical and chemical distinctions

    International Nuclear Information System (INIS)

    Long, Christopher M.; Nascarella, Marc A.; Valberg, Peter A.

    2013-01-01

    Airborne particles containing elemental carbon (EC) are currently at the forefront of scientific and regulatory scrutiny, including black carbon, carbon black, and engineered carbon-based nanomaterials, e.g., carbon nanotubes, fullerenes, and graphene. Scientists and regulators sometimes group these EC-containing particles together, for example, interchangeably using the terms carbon black and black carbon despite one being a manufactured product with well-controlled properties and the other being an undesired, incomplete-combustion byproduct with diverse properties. In this critical review, we synthesize information on the contrasting properties of EC-containing particles in order to highlight significant differences that can affect hazard potential. We demonstrate why carbon black should not be considered a model particle representative of either combustion soots or engineered carbon-based nanomaterials. Overall, scientific studies need to distinguish these highly different EC-containing particles with care and precision so as to forestall unwarranted extrapolation of properties, hazard potential, and study conclusions from one material to another. -- Highlights: •Major classes of elemental carbon-containing particles have distinct properties. •Despite similar names, carbon black should not be confused with black carbon. •Carbon black is distinguished by a high EC content and well-controlled properties. •Black carbon particles are characterized by their heterogenous properties. •Carbon black is not a model particle representative of engineered nanomaterials. -- This review demonstrates the significant physical and chemical distinctions between elemental carbon-containing particles e.g., carbon black, black carbon, and engineered nanomaterials

  2. Examining African self-consciousness and Black racial identity as predictors of Black men's psychological well-being.

    Science.gov (United States)

    Pierre, Martin R; Mahalik, James R

    2005-02-01

    This study investigated African self-consciousness and Black racial identity as predictors of psychological distress and self-esteem for Black men. One hundred thirty Black men from a college and community sample completed the African Self-Consciousness Scale, the Racial Identity Attitude Scale-B, the Symptom Checklist 90-Revised, and the Coopersmith Self-Esteem Inventory. Canonical correlation analysis found 2 significant roots with the 1st root indicating that Black men whose attitudes reflected Preencounter and Immersion racial identity attitudes and who do not resist against anti-African/Black forces reported greater psychological distress and less esteem. Results from the 2nd root suggested that Black men whose attitudes reflect greater Internalization racial identity attitudes, greater resistance to anti-African/Black forces, and less identification with Blacks reported greater self-esteem. ((c) 2005 APA, all rights reserved).

  3. The angry black woman: the impact of pejorative stereotypes on psychotherapy with black women.

    Science.gov (United States)

    Ashley, Wendy

    2014-01-01

    In the aftermath of slavery and the resulting social, economic, and political effects, Black women have become the victims of negative stereotyping in mainstream American culture. Such stereotypes include the myth of the angry Black woman that characterizes these women as aggressive, ill tempered, illogical, overbearing, hostile, and ignorant without provocation. Symptoms presented by Black women during mental health treatment may reinforce this myth. However, many of the negative characteristics of the angry Black woman developed in response to external stressors and historical factors. Black women also have a unique experience with and expressions of anger that shape the presenting symptoms interpreted by the mental health clinician. This myth and corresponding negative stereotypes significantly affect Black women intrapsychically, interpersonally, and are likely to influence the efficacy of mental health treatment. Understanding and treatment of Black women in a mental health context should be influenced by the cultural norms and sociopolitical dynamics affecting these clients. Successful mental health treatment requires cultural competence and clinicians who are well prepared to navigate the inherent complexities of culture with clients. Awareness of the angry Black woman mythology, including its genesis, manifestations, and the unique experiences of Black women, may raise the standards of cultural competence for clinicians and provide more successful treatment outcomes in working with this population. A case example illustrates the assiduity essential to practicing in a culturally competent manner. A client is presented from a traditional psychotherapeutic perspective and then viewed through a lens that integrates psychotherapeutic practice with conscious awareness of the mythology and stereotypes impacting Black women. Implications for culturally relevant practice are discussed.

  4. Over spinning a black hole?

    Energy Technology Data Exchange (ETDEWEB)

    Bouhmadi-Lopez, Mariam; Cardoso, Vitor; Nerozzi, Andrea; Rocha, Jorge V, E-mail: mariam.bouhmadi@ist.utl.pt, E-mail: vitor.cardoso@ist.utl.pt, E-mail: andrea.nerozzi@ist.utl.pt, E-mail: jorge.v.rocha@ist.utl.pt [CENTRA, Department de Fisica, Instituto Superior Tecnico, Av. Rovisco Pais 1, 1049 Lisboa (Portugal)

    2011-09-22

    A possible process to destroy a black hole consists on throwing point particles with sufficiently large angular momentum into the black hole. In the case of Kerr black holes, it was shown by Wald that particles with dangerously large angular momentum are simply not captured by the hole, and thus the event horizon is not destroyed. Here we reconsider this gedanken experiment for black holes in higher dimensions. We show that this particular way of destroying a black hole does not succeed and that Cosmic Censorship is preserved.

  5. Lung clearance of inhaled particles after exposure to carbon black generated from a resuspension system

    International Nuclear Information System (INIS)

    Lee, P.S.; Gorski, R.A.; Hering, W.E.; Chan, T.L.

    1987-01-01

    A system to resuspend carbon black particles for providing submicron aerosols for inhalation exposure studies has been developed. The effect of continuous exposure to carbonaceous material (as a surrogate for the carbonaceous particles in diesel exhaust) on the pulmonary clearance of inhaled diesel tracer particles was studied in male Fischer 344 rats. Submicron carbon black particles with a mass median aerodynamic diameter (MMAD) of 0.22 micron and a size distribution similar to that of exhaust particles from a GM 5.7-liter diesel engine were successfully generated and administered to test animals at a nominal concentration of 6 mg/m3 for 20 hr/day, 7 days/week, for periods lasting 1 to 11 weeks. Immediately after the carbon black exposure, test animals were administered 14 C-tagged diesel particles for 45 min in a nose-only chamber. The pulmonary retention of inhaled radioactive tracer particles was determined at preselected time intervals. Based upon the data collected up to 1 year postexposure, prolonged exposure to carbon black particles exhibits a similar inhibitory effect on pulmonary clearance as does prolonged exposure to diesel exhaust with a comparable particulate dose. This observation indicates that the excessive accumulation of carbonaceous material may be the predominant factor affecting lung clearance

  6. Adaptability of black walnut, black cherry, and Northern red oak to Northern California

    Science.gov (United States)

    Philip M. McDonald

    1987-01-01

    When planted in sheltered sites in northern California, only 49% of black walnut (Juglans nigra L.) and 58% of black cherry (Prunus serotina Ehrh.) survived for 15 years, and 20% of northern red oak (Quercus rubra L.) survived for 10 years. The black walnut trees averaged 0.6 inches diameter at breast...

  7. Black Holes in Higher Dimensions

    Directory of Open Access Journals (Sweden)

    Reall Harvey S.

    2008-09-01

    Full Text Available We review black-hole solutions of higher-dimensional vacuum gravity and higher-dimensional supergravity theories. The discussion of vacuum gravity is pedagogical, with detailed reviews of Myers–Perry solutions, black rings, and solution-generating techniques. We discuss black-hole solutions of maximal supergravity theories, including black holes in anti-de Sitter space. General results and open problems are discussed throughout.

  8. Black hole decay as geodesic motion

    International Nuclear Information System (INIS)

    Gupta, Kumar S.; Sen, Siddhartha

    2003-01-01

    We show that a formalism for analyzing the near-horizon conformal symmetry of Schwarzschild black holes using a scalar field probe is capable of describing black hole decay. The equation governing black hole decay can be identified as the geodesic equation in the space of black hole masses. This provides a novel geometric interpretation for the decay of black holes. Moreover, this approach predicts a precise correction term to the usual expression for the decay rate of black holes

  9. Yoghurt kedelai hitam (black soyghurt dapat menurunkan kadar LDL tikus hiperkolesterolemia

    Directory of Open Access Journals (Sweden)

    Slamet Riyanto

    2016-08-01

    Full Text Available ABSTRACTBackground: Hypercholesterolemia is a main risk factor of cardiovascular disease that remains the higher cause of deaths in the world. Black soy bean containing protein, fiber, vitamin, isoflavon, and flavonoid can decrease serum cholesterol level. Yoghurt contains lactic acid bacteria that decrease total and LDL cholesterol, triglyceride, and increase the HDL cholesterol. Processing of black soy bean into black soyghurt can increase its isoflavon’s activity by forming aglicone, which has higher activity to decrease cholesterol.Objectives: To know the effect of black soyghurt feeding to LDL, HDL, and HDL ratio of hypercholesterolemic rats.Methods: This research was true-experimental using post test only with control group design. Subjects were 20 male Sprague dawley rats, 2 months old, inducted hypercholesterolemia, given black soyghurt diet using 2 mL, 3 mL, and 4 mL dosage for 21 days. Serum lipid profile were measured by CHOD-PAPand GPO-PAP methods respectively. Normality of the data were tested by Shapiro Wilks test. Data were analyzed by paired t test and Anova continued by LSD test using computer program.Results: The study revealed that black soyghurt 4 mL/day decreased LDL (p=0.02 at the most significant level. The other doses did not significantly influence the levels of LDL (p>0.05 . There was also no effect of black soyghurt feeding on serum HDL cholesterol levels (p=0.11 and the ratio of LDL /HDL (p=0.087.Conclusions: The feeding of black soyghurt at the dosage of 4 mL/day to hypercholesterolemic rats could decrease the serum LDL, but could decrease the ratio of LDL / HDL significantly.KEYWORDS: black soyghurt, LDL/HDL ratio, hypercholesterolemicABSTRAKLatar belakang: Hiperkolesterolemia merupakan faktor risiko penyakit kardiovaskuler yang menjadi penyebab kematian utama di dunia. Kedelai hitam mengandung protein, vitamin, serat, isoflavon, dan flavonoid yang mampu menurunkan kadar kolesterol. Yoghurt

  10. The Black Atlantic as reversal: A reappraisal of African and black theology

    Directory of Open Access Journals (Sweden)

    Hans Engdahl

    2017-09-01

    Full Text Available In this article, I will try to do three things. Firstly, pay attention to the notion of Black Atlantic as coined by Paul Gilroy, which in effect could signify a reversal of colonialism and slavery. Secondly, revisit the 1970s and the debate about the relevance of Black theology vis-à-vis African theology, using John Mbiti’s article ‘An African Views American Black Theology’ as entry point. Here, I will discuss contributions also made by Desmond Tutu and James Cone. Thirdly, starting with the premise that both theologies are relevant and soul mates today, which would (probably be confirmed by all the above mentioned at this point in time, an assessment of current voices will be made, that is, Tinyiko Maluleke and Vuyani Vellem on black and African ecclesiologies from a South African perspective, and Lawrence Burnley on the fate of the Black Church in the United States.

  11. The Tuskegee Syphilis Study, 1932 to 1972: implications for HIV education and AIDS risk education programs in the black community.

    Science.gov (United States)

    Thomas, S B; Quinn, S C

    1991-01-01

    The Tuskegee study of untreated syphilis in the Negro male is the longest nontherapeutic experiment on human beings in medical history. The strategies used to recruit and retain participants were quite similar to those being advocated for HIV/AIDS prevention programs today. Almost 60 years after the study began, there remains a trail of distrust and suspicion that hampers HIV education efforts in Black communities. The AIDS epidemic has exposed the Tuskegee study as a historical marker for the legitimate discontent of Blacks with the public health system. The belief that AIDS is a form of genocide is rooted in a social context in which Black Americans, faced with persistent inequality, believe in conspiracy theories about Whites against Blacks. These theories range from the belief that the government promotes drug abuse in Black communities to the belief that HIV is a manmade weapon of racial warfare. An open and honest discussion of the Tuskegee Syphilis Study can facilitate the process of rebuilding trust between the Black community and public health authorities. This dialogue can contribute to the development of HIV education programs that are scientifically sound, culturally sensitive, and ethnically acceptable. Images p1500-a p1502-a p1503-a PMID:1951814

  12. Black report up-date

    International Nuclear Information System (INIS)

    1988-12-01

    In 1984, the Black Report published its results on the incidence of cancer and leukaemia in under 25-year olds in the village of Seascale and the surrounding area near the Sellafield nuclear reprocessing plant. Since then the pressure group core, as a result of their own independent research, has discovered ten additional cases of childhood cancer which should have been included in the Black Report and a Further two cases since the Black Report was written. This represents an additional 31% over the initial numbers considered and a review of the Black Report is sought. (UK)

  13. Lifshitz topological black holes

    International Nuclear Information System (INIS)

    Mann, R.B.

    2009-01-01

    I find a class of black hole solutions to a (3+1) dimensional theory gravity coupled to abelian gauge fields with negative cosmological constant that has been proposed as the dual theory to a Lifshitz theory describing critical phenomena in (2+1) dimensions. These black holes are all asymptotic to a Lifshitz fixed point geometry and depend on a single parameter that determines both their area (or size) and their charge. Most of the solutions are obtained numerically, but an exact solution is also obtained for a particular value of this parameter. The thermodynamic behaviour of large black holes is almost the same regardless of genus, but differs considerably for small black holes. Screening behaviour is exhibited in the dual theory for any genus, but the critical length at which it sets in is genus-dependent for small black holes.

  14. Acceleration of black hole universe

    Science.gov (United States)

    Zhang, T. X.; Frederick, C.

    2014-01-01

    Recently, Zhang slightly modified the standard big bang theory and developed a new cosmological model called black hole universe, which is consistent with Mach's principle, governed by Einstein's general theory of relativity, and able to explain all observations of the universe. Previous studies accounted for the origin, structure, evolution, expansion, and cosmic microwave background radiation of the black hole universe, which grew from a star-like black hole with several solar masses through a supermassive black hole with billions of solar masses to the present state with hundred billion-trillions of solar masses by accreting ambient matter and merging with other black holes. This paper investigates acceleration of the black hole universe and provides an alternative explanation for the redshift and luminosity distance measurements of type Ia supernovae. The results indicate that the black hole universe accelerates its expansion when it accretes the ambient matter in an increasing rate. In other words, i.e., when the second-order derivative of the mass of the black hole universe with respect to the time is positive . For a constant deceleration parameter , we can perfectly explain the type Ia supernova measurements with the reduced chi-square to be very close to unity, χ red˜1.0012. The expansion and acceleration of black hole universe are driven by external energy.

  15. Why Blue-Collar Blacks Help Less

    OpenAIRE

    Smith, Sandra Susan; Young, Kara Alexis

    2013-01-01

    Why are blue-collar blacks less likely to help jobseekers than jobholders from other ethnoracial groups or even than more affluent blacks? Drawing from in-depth, semi-structured interviews with 97 black and Latino workers at one large, public sector employer, we find that blue-collar black workers both helped less proactively and rejected more requests for assistance than did blue-collar Latino and white-collar black workers. We attribute blue-collar blacks’ more passive engagement to their...

  16. The White Male as Narrative Axis in Mayra Santos-Febres’s Nuestra señora de la noche

    Directory of Open Access Journals (Sweden)

    Helene C. Weldt-Basson

    2013-01-01

    Full Text Available Mayra Santos-Febres’s 2006 novel, Nuestra señora de la noche , is based on the life of the Puerto Rican madam, Isabel la Negra, a legendary figure in Puerto Rican culture. Using both Mervin Alleyne’s theory of racial discrimination and Aída Hurtado’s theory of racially-based gender discrimination, which shows how the reactions of white and black females are governed by their relation of dependency on or rejection by the white male, this study illustrates how the character Isabel la Negra evolves as a postmodern, feminist character who opposes racism and gender subordination in Puerto Rico through her role as a prostitute. Conversely, the study also illustrates how madness, associated with both white (Cristina Rangel and black (Montse females in the novel, is a powerless rather than feminist strategy, into which women descend due to their mistreatment by patriarchal society. The study illustrates how Fernando Fornarís, the white male protagonist, serves as the narrative axis for the development of women’s polarized reactions to patriarchal domination in the novel.

  17. Curvature invariant characterization of event horizons of four-dimensional black holes conformal to stationary black holes

    Science.gov (United States)

    McNutt, David D.

    2017-11-01

    We introduce three approaches to generate curvature invariants that transform covariantly under a conformal transformation of a four-dimensional spacetime. For any black hole conformally related to a stationary black hole, we show how a set of conformally covariant invariants can be combined to produce a conformally covariant invariant that detects the event horizon of the conformally related black hole. As an application we consider the rotating dynamical black holes conformally related to the Kerr-Newman-Unti-Tamburino-(anti)-de Sitter spacetimes and construct an invariant that detects the conformal Killing horizon along with a second invariant that detects the conformal stationary limit surface. In addition, we present necessary conditions for a dynamical black hole to be conformally related to a stationary black hole and apply these conditions to the ingoing Kerr-Vaidya and Vaidya black hole solutions to determine if they are conformally related to stationary black holes for particular choices of the mass function. While two of the three approaches cannot be generalized to higher dimensions, we discuss the existence of a conformally covariant invariant that will detect the event horizon for any higher dimensional black hole conformally related to a stationary black hole which admits at least two conformally covariant invariants, including all vacuum spacetimes.

  18. Music Videos as Black Feminist Thought – From Nicki Minaj’s Anaconda to Beyoncé’s Formation

    Directory of Open Access Journals (Sweden)

    Katariina Kyrölä

    2017-10-01

    Full Text Available The article examines two recent music videos by Black female artists, Nicki Minaj’s Anaconda (2014 and Beyoncé’s Formation (2016, and the heated online discussions around them about whether they are feminist or not. The article argues that the epistemic habit of asking this question often works counterproductively and stabilises the boundaries of feminism. Instead, the two music videos are considered as creative works of Black feminist thought, following Patricia Hill Collins (2009. Collins suggests that in order to challenge traditional forms of white male knowledge production, other forms of expression than academic writing should also be considered theory. The key question then becomes: how do Anaconda and Formation participate in, re-imagine and work as Black feminist thought, understood as complex and dynamic? The article outlines three main critiques directed at the videos: selling out to white people and capitalism; promotion of white, heteronormative body ideals while appropriating queer of color culture; and involvement in so-called ‘reverse oppression’. Anaconda and Formation can be seen to answer each these critiques respectively, when seen connected to and employing strategies of Black feminist theories of pleasure, queer of color critique, and Black feminist politics of coalition among marginalised subjects.

  19. New geometries for black hole horizons

    Energy Technology Data Exchange (ETDEWEB)

    Armas, Jay [Physique Théorique et Mathématique,Université Libre de Bruxelles and International Solvay Institutes, ULB-Campus Plaine CP231, B-1050 Brussels (Belgium); Blau, Matthias [Albert Einstein Center for Fundamental Physics, University of Bern,Sidlerstrasse 5, 3012 Bern (Switzerland)

    2015-07-10

    We construct several classes of worldvolume effective actions for black holes by integrating out spatial sections of the worldvolume geometry of asymptotically flat black branes. This provides a generalisation of the blackfold approach for higher-dimensional black holes and yields a map between different effective theories, which we exploit by obtaining new hydrodynamic and elastic transport coefficients via simple integrations. Using Euclidean minimal surfaces in order to decouple the fluid dynamics on different sections of the worldvolume, we obtain local effective theories for ultraspinning Myers-Perry branes and helicoidal black branes, described in terms of a stress-energy tensor, particle currents and non-trivial boost vectors. We then study in detail and present novel compact and non-compact geometries for black hole horizons in higher-dimensional asymptotically flat space-time. These include doubly-spinning black rings, black helicoids and helicoidal p-branes as well as helicoidal black rings and helicoidal black tori in D≥6.

  20. Statistical mechanics of black holes

    International Nuclear Information System (INIS)

    Harms, B.; Leblanc, Y.

    1992-01-01

    We analyze the statistical mechanics of a gas of neutral and charged black holes. The microcanonical ensemble is the only possible approach to this system, and the equilibrium configuration is the one for which most of the energy is carried by a single black hole. Schwarzschild black holes are found to obey the statistical bootstrap condition. In all cases, the microcanonical temperature is identical to the Hawking temperature of the most massive black hole in the gas. U(1) charges in general break the bootstrap property. The problems of black-hole decay and of quantum coherence are also addressed

  1. Few-layer black phosphorus nanoparticles.

    Science.gov (United States)

    Sofer, Zdenek; Bouša, Daniel; Luxa, Jan; Mazanek, Vlastimil; Pumera, Martin

    2016-01-28

    Herein, black phosphorus quantum dots and nanoparticles of a few layer thickness were prepared and characterized using STEM, AFM, dynamic light scattering, X-ray photoelectron spectroscopy, X-ray diffraction, Raman spectroscopy and photoluminescence. Impact electrochemistry of the induvidual black phosphorus nanoparticles allows their size determination. The centrifugation of colloidal black phosphorus nanoparticles allowed separation of quantum dots with sizes up to 15 nm. These black phosphorus nanoparticles exhibit a large band gap and are expected to find a wide range of applications from semiconductors to biomolecule tags. The use of black phosphorus nanoparticles for vapour sensing was successfully demonstrated.

  2. Green tea supplementation produces better neuroprotective effects than red and black tea in Alzheimer-like rat model.

    Science.gov (United States)

    Schimidt, Helen L; Garcia, Alexandre; Martins, Alexandre; Mello-Carpes, Pamela B; Carpes, Felipe P

    2017-10-01

    Green tea from Camellia sinensis plays a neuroprotective role in different neurodegenerative conditions, such as memory deficits in Alzheimer disease (AD). However, whether other teas from Camellia sinensis present similar neuroprotective effect still is not clear. Here we investigate effects of green, red and black tea supplementation on memory and hippocampus oxidative status in a rat model of Alzheimer-like disease (AD-like). Wistar male rats were supplemented with green, red or black tea during 8weeks before Aβ intra-hippocampal injection (2μL of Aβ-25-35, CA1 region). AD and sham rats were submitted to memory tests. After euthanasia, oxidative status in the bilateral hippocampus was quantified. Green and red teas avoid memory deficits in AD rats, but only green tea also avoids oxidative stress and damage in the hippocampus. Green tea was more effective for neuroprotection than red and black teas from the Camellia sinensis in the AD rat model. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Regular black hole in three dimensions

    OpenAIRE

    Myung, Yun Soo; Yoon, Myungseok

    2008-01-01

    We find a new black hole in three dimensional anti-de Sitter space by introducing an anisotropic perfect fluid inspired by the noncommutative black hole. This is a regular black hole with two horizons. We compare thermodynamics of this black hole with that of non-rotating BTZ black hole. The first-law of thermodynamics is not compatible with the Bekenstein-Hawking entropy.

  4. Two regimes of HIV/AIDS: The MMWR and the socio-political construction of HIV/AIDS as a 'black disease'.

    Science.gov (United States)

    Moseby, Kevin M

    2017-09-01

    Over the course of the HIV/AIDS epidemic, black Americans have become a central target of US public health prevention efforts. And today, HIV/AIDS is understood to disproportionately affect black Americans. This markedly contrasts with knowledge about the disease and efforts to prevent it in the first decade of the epidemic in the US, when expert and lay understandings and responses centred on white gay males. This article demonstrates that explaining these historical reversals as purely reflective of epidemiological data - or best knowledge available - is insufficient. Drawing on the concept disease regimes and utilising a discursive analysis of epidemiological results and editorial commentary published from 1981 to 1994 in the Morbidity and Mortality Weekly Reports (MMWR), this article argues for a socio-political explanation for the changing colour of HIV/AIDS. That is, it scrutinises institutional and discursive practices that within the HIV/AIDS prevention field and disease discourse constituted a 'regime of black American exclusion' (1981-1992) and a 'regime of black American inclusion (1993-present day). © 2017 Foundation for the Sociology of Health & Illness.

  5. Boosted quantum black hole and black string in M-theory, and quantum correction to Gregory-Laflamme instability

    Energy Technology Data Exchange (ETDEWEB)

    Hyakutake, Yoshifumi [Faculty of Science, Ibaraki University,Bunkyo 2-1-1, Mito, Ibaraki, 310-8512 (Japan)

    2015-09-11

    We take into account higher derivative R{sup 4} corrections in M-theory and construct quantum black hole and black string solutions in 11 dimensions up to the next leading order. The quantum black string is stretching along the 11th direction and the Gregory-Laflamme instability is examined at the quantum level. Thermodynamics of the boosted quantum black hole and black string are also discussed. Especially we take the near horizon limit of the quantum black string and investigate its instability quantitatively.

  6. Stationary black holes: large D analysis

    International Nuclear Information System (INIS)

    Suzuki, Ryotaku; Tanabe, Kentaro

    2015-01-01

    We consider the effective theory of large D stationary black holes. By solving the Einstein equations with a cosmological constant using the 1/D expansion in near zone of the black hole we obtain the effective equation for the stationary black hole. The effective equation describes the Myers-Perry black hole, bumpy black holes and, possibly, the black ring solution as its solutions. In this effective theory the black hole is represented as an embedded membrane in the background, e.g., Minkowski or Anti-de Sitter spacetime and its mean curvature is given by the surface gravity redshifted by the background gravitational field and the local Lorentz boost. The local Lorentz boost property of the effective equation is observed also in the metric itself. In fact we show that the leading order metric of the Einstein equation in the 1/D expansion is generically regarded as a Lorentz boosted Schwarzschild black hole. We apply this Lorentz boost property of the stationary black hole solution to solve perturbation equations. As a result we obtain an analytic formula for quasinormal modes of the singly rotating Myers-Perry black hole in the 1/D expansion.

  7. Black branes as piezoelectrics.

    Science.gov (United States)

    Armas, Jay; Gath, Jakob; Obers, Niels A

    2012-12-14

    We find a realization of linear electroelasticity theory in gravitational physics by uncovering a new response coefficient of charged black branes, exhibiting their piezoelectric behavior. Taking charged dilatonic black strings as an example and using the blackfold approach we measure their elastic and piezolectric moduli. We also use our results to draw predictions about the equilibrium condition of charged dilatonic black rings in dimensions higher than six.

  8. Science identity possibilities: a look into Blackness, masculinities, and economic power relations

    Science.gov (United States)

    Rosa, Katemari

    2018-02-01

    This forum paper dialogues with Sheron Mark's A bit of both science and economics: a non-traditional STEM identity narrative. In her paper, she discusses the development of a Science, Technology, Engineering, and Mathematics (STEM) identity by a young African American male during an informal STEM for Social Justice Program. Here, the discussion focuses on Black masculinities, identity formation, and the role of science educators in making STEM fields a welcoming place for young Black men. Drawing from Mark's data and discussion, this paper is a dialogue between science identity possibilities in the United States and in Brazil when we look at the intersections of race, gender, and socioeconomic status. Using the shared colonial past of both countries a connection is established to address race relations within science education. The main argument in this paper is that racism can no longer be denied and dismissed by the science education community worldwide and that intersectional approaches are needed to face this issue.

  9. Black hole levitron

    NARCIS (Netherlands)

    Arsiwalla, X.D.; Verlinde, E.P.

    2010-01-01

    We study the problem of spatially stabilizing four dimensional extremal black holes in background electric/magnetic fields. Whilst looking for stationary stable solutions describing black holes placed in external fields we find that taking a continuum limit of Denef et al.’s multicenter

  10. Sexual Violence Among Male Inmates.

    Science.gov (United States)

    Hilinski-Rosick, Carly M; Freiburger, Tina L

    2018-04-01

    Inmate misconduct has been a widely studied topic for many decades. General studies of misconduct have found that there are certain factors that contribute to misconduct, including age, gender, sentence length, and facility type. Few studies, however, have examined the factors predicting sexual offenses in a prison conduct. Although many studies of victims of sexual offenses in prison have been conducted, there is a lack of studies examining the perpetrators of prison sexual violence. The current study attempted to expand this body of literature by examining the correlates of sexual misconduct among a sample of male inmates incarcerated in the state of North Carolina during 2010. Deprivation and importation theories of inmate behavior were used to guide the analysis, and measures of deprivation and importation factors were both included in the analytical models. Findings indicate that Black, nonmarried, younger inmates, who had more previous incarcerations and had been incarcerated longer, had greater odds of having a sexual infraction. Additional findings, as well as policy implications, are discussed.

  11. Black Hole Grabs Starry Snack

    Science.gov (United States)

    2006-01-01

    [figure removed for brevity, see original site] Poster Version This artist's concept shows a supermassive black hole at the center of a remote galaxy digesting the remnants of a star. NASA's Galaxy Evolution Explorer had a 'ringside' seat for this feeding frenzy, using its ultraviolet eyes to study the process from beginning to end. The artist's concept chronicles the star being ripped apart and swallowed by the cosmic beast over time. First, the intact sun-like star (left) ventures too close to the black hole, and its own self-gravity is overwhelmed by the black hole's gravity. The star then stretches apart (middle yellow blob) and eventually breaks into stellar crumbs, some of which swirl into the black hole (cloudy ring at right). This doomed material heats up and radiates light, including ultraviolet light, before disappearing forever into the black hole. The Galaxy Evolution Explorer was able to watch this process unfold by observing changes in ultraviolet light. The area around the black hole appears warped because the gravity of the black hole acts like a lens, twisting and distorting light.

  12. A nonsingular rotating black hole

    International Nuclear Information System (INIS)

    Ghosh, Sushant G.

    2015-01-01

    The spacetime singularities in classical general relativity are inevitable, as predicated by the celebrated singularity theorems. However, it is a general belief that singularities do not exist in Nature and that they are the limitations of the general relativity. In the absence of a welldefined quantum gravity, models of regular black holes have been studied. We employ a probability distribution inspired mass function m(r) to replace the Kerr black hole mass M to represent a nonsingular rotating black hole that is identified asymptotically (r >> k, k > 0 constant) exactly as the Kerr-Newman black hole, and as the Kerr black hole when k = 0. The radiating counterpart renders a nonsingular generalization of Carmeli's spacetime as well as Vaidya's spacetime, in the appropriate limits. The exponential correction factor changing the geometry of the classical black hole to remove the curvature singularity can also be motivated by quantum arguments. The regular rotating spacetime can also be understood as a black hole of general relativity coupled to nonlinear electrodynamics. (orig.)

  13. Thermodynamic theory of black holes

    Energy Technology Data Exchange (ETDEWEB)

    Davies, P C.W. [King' s Coll., London (UK). Dept. of Mathematics

    1977-04-21

    The thermodynamic theory underlying black hole processes is developed in detail and applied to model systems. It is found that Kerr-Newman black holes undergo a phase transition at a = 0.68M or Q = 0.86M, where the heat capacity has an infinite discontinuity. Above the transition values the specific heat is positive, permitting isothermal equilibrium with a surrounding heat bath. Simple processes and stability criteria for various black hole situations are investigated. The limits for entropically favoured black hole formation are found. The Nernst conditions for the third law of thermodynamics are not satisfied fully for black holes. There is no obvious thermodynamic reason why a black hole may not be cooled down below absolute zero and converted into a naked singularity. Quantum energy-momentum tensor calculations for uncharged black holes are extended to the Reissner-Nordstrom case, and found to be fully consistent with the thermodynamic picture for Q < M. For Q < M the model predicts that 'naked' collapse also produces radiation, with such intensity that the collapsing matter is entirely evaporated away before a naked singularity can form.

  14. NASA Observatory Confirms Black Hole Limits

    Science.gov (United States)

    2005-02-01

    The very largest black holes reach a certain point and then grow no more, according to the best survey to date of black holes made with NASA's Chandra X-ray Observatory. Scientists have also discovered many previously hidden black holes that are well below their weight limit. These new results corroborate recent theoretical work about how black holes and galaxies grow. The biggest black holes, those with at least 100 million times the mass of the Sun, ate voraciously during the early Universe. Nearly all of them ran out of 'food' billions of years ago and went onto a forced starvation diet. Focus on Black Holes in the Chandra Deep Field North Focus on Black Holes in the Chandra Deep Field North On the other hand, black holes between about 10 and 100 million solar masses followed a more controlled eating plan. Because they took smaller portions of their meals of gas and dust, they continue growing today. "Our data show that some supermassive black holes seem to binge, while others prefer to graze", said Amy Barger of the University of Wisconsin in Madison and the University of Hawaii, lead author of the paper describing the results in the latest issue of The Astronomical Journal (Feb 2005). "We now understand better than ever before how supermassive black holes grow." One revelation is that there is a strong connection between the growth of black holes and the birth of stars. Previously, astronomers had done careful studies of the birthrate of stars in galaxies, but didn't know as much about the black holes at their centers. DSS Optical Image of Lockman Hole DSS Optical Image of Lockman Hole "These galaxies lose material into their central black holes at the same time that they make their stars," said Barger. "So whatever mechanism governs star formation in galaxies also governs black hole growth." Astronomers have made an accurate census of both the biggest, active black holes in the distance, and the relatively smaller, calmer ones closer by. Now, for the first

  15. Erratic Black Hole Regulates Itself

    Science.gov (United States)

    2009-03-01

    New results from NASA's Chandra X-ray Observatory have made a major advance in explaining how a special class of black holes may shut off the high-speed jets they produce. These results suggest that these black holes have a mechanism for regulating the rate at which they grow. Black holes come in many sizes: the supermassive ones, including those in quasars, which weigh in at millions to billions of times the mass of the Sun, and the much smaller stellar-mass black holes which have measured masses in the range of about 7 to 25 times the Sun's mass. Some stellar-mass black holes launch powerful jets of particles and radiation, like seen in quasars, and are called "micro-quasars". The new study looks at a famous micro-quasar in our own Galaxy, and regions close to its event horizon, or point of no return. This system, GRS 1915+105 (GRS 1915 for short), contains a black hole about 14 times the mass of the Sun that is feeding off material from a nearby companion star. As the material swirls toward the black hole, an accretion disk forms. This system shows remarkably unpredictable and complicated variability ranging from timescales of seconds to months, including 14 different patterns of variation. These variations are caused by a poorly understood connection between the disk and the radio jet seen in GRS 1915. Chandra, with its spectrograph, has observed GRS 1915 eleven times since its launch in 1999. These studies reveal that the jet in GRS 1915 may be periodically choked off when a hot wind, seen in X-rays, is driven off the accretion disk around the black hole. The wind is believed to shut down the jet by depriving it of matter that would have otherwise fueled it. Conversely, once the wind dies down, the jet can re-emerge. "We think the jet and wind around this black hole are in a sort of tug of war," said Joseph Neilsen, Harvard graduate student and lead author of the paper appearing in the journal Nature. "Sometimes one is winning and then, for reasons we don

  16. Atypical features of hyperthyroidism in Blacks

    International Nuclear Information System (INIS)

    Kalk, W.J.

    1980-01-01

    Hyperthyroidism is reportedly uncommon in the indigenous populations of Africa. The presenting symptoms volunteered, the symptoms elicited by direct questioning, and the results of physical examination were therefore prospectively compared in 60 Black and 56 White patients with thyrotoxicosis attending a single thyroid clinic. Fewer Blacks than Whites volunteered information about weight loss, while more Blacks complained only of the presence of a goitre. A 'chance' diagnosis of hyperthyroidism was made more frequently in Blacks. Symptomatology elicited by direct questioning and findings on physical examination were generally similar in each group, except that Blacks presented more frequently with complicated disease (cardiac failure and overt myopathy) and infiltrative ophthalmopathy. The frequency with which hyperthyroidism presents 'atypically' in Black compared with White patients may reflect educational, socio-economic and cultural differences in the Black and White populations, and may partly explain the infrequency with which this disease is diagnosed in Blacks

  17. Black layers on historical architecture.

    Science.gov (United States)

    Toniolo, Lucia; Zerbi, Carlotta M; Bugini, Roberto

    2009-03-01

    The external surface of any building in urban polluted environment is unavoidably destined to be covered with layers that assume a grey to black colour and are generally called 'black crusts'. These, according to standard protocols and glossary, are deteriorated surface layers of stone material; they can have variable thickness, are hard and fragile and can detach spontaneously from the substrate, which, in general, is quite decayed. Plain visual examination may lead to consider 'black crusts' all similar, whilst only a careful diagnostic investigation can distinguish 'black crusts' and the consequences of their formation on stone substrates. In this paper, various black layers on marble are studied and compared and the morphological and compositional characteristics discussed according to the related mechanisms of formation. Differences between old (hundred years) and recent crusts (30 years) are investigated and pointed out. Samples of black crusts collected from the Milan Cathedral façade (Candoglia Marble) have been studied and compared with the careful and synergic employ of traditional techniques: optical (transmission and reflected VIS light) and electron microscopy, X-ray spectrometry and micro-Fourier transform infrared spectroscopy. Visual examination of loose fragments does not allow to point out outstanding differences amongst the various samples; black layers have similar main mineral components, gypsum and airborne particles, with different spatial distribution. The microscopic studies allowed to point out the porosity differences, the gypsum crystallisation habit, different amount of embedded particles, level and progress of marble decay. The observations lead to define three main types of black crusts: black crust deriving from marble sulphation, compact deposit and encrustation due to exogenic materials deposition. Black crusts show evidence of sulphation in progress, without a clear continuity solution between crust and marble; the lack of

  18. "Expressive Cool" and the Paradox of Black and White Males' Neighborhood Socialization toward Education

    Science.gov (United States)

    Johnson, Odis, Jr.

    2018-01-01

    This study explores how linkages between adolescents' educational attitudes and achievement vary according to race, expressive culture, and neighborhood collective socialization qualities. Specifically, the study examines (a) racial differences in how males' educational attitudes relate to their academic performance (i.e.,…

  19. Studies on thyroid activity at sexual maturity in the male and female Bengal goats

    International Nuclear Information System (INIS)

    Varshney, V.P.; Pande, J.K.; Sanwal, P.C.

    1980-01-01

    Thyroid activity at sexual maturity in the male and female Black Bengal goats was investigated. No change could be recorded at the attainment of sexual maturity in either of the sexes. The cyclic female goats also failed to reflect any change in the thyroid activity during any phase of the oestrous cycle. Again the male goats also failed to reflect any differences in the thyroid activity from the females, either during their immature, or during their mature life. The observations presented thus reflect that the thyroid activity in goats is not influenced by the attainments of sexual maturity or by the sex, in this species. The thyroid gland activity was assessed by using the in vitro technique of triiodothyronine- 125 I uptake by resin. (author)

  20. Nonsingular black hole

    Energy Technology Data Exchange (ETDEWEB)

    Chamseddine, Ali H. [American University of Beirut, Physics Department, Beirut (Lebanon); I.H.E.S., Bures-sur-Yvette (France); Mukhanov, Viatcheslav [Niels Bohr Institute, Niels Bohr International Academy, Copenhagen (Denmark); Ludwig-Maximilians University, Theoretical Physics, Munich (Germany); MPI for Physics, Munich (Germany)

    2017-03-15

    We consider the Schwarzschild black hole and show how, in a theory with limiting curvature, the physical singularity ''inside it'' is removed. The resulting spacetime is geodesically complete. The internal structure of this nonsingular black hole is analogous to Russian nesting dolls. Namely, after falling into the black hole of radius r{sub g}, an observer, instead of being destroyed at the singularity, gets for a short time into the region with limiting curvature. After that he re-emerges in the near horizon region of a spacetime described by the Schwarzschild metric of a gravitational radius proportional to r{sub g}{sup 1/3}. In the next cycle, after passing the limiting curvature, the observer finds himself within a black hole of even smaller radius proportional to r{sub g}{sup 1/9}, and so on. Finally after a few cycles he will end up in the spacetime where he remains forever at limiting curvature. (orig.)

  1. Black Teenage Pregnancy

    Directory of Open Access Journals (Sweden)

    Loretta I. Winters

    2012-01-01

    Full Text Available This article examines the relative importance of race and socioeconomic status (SES in determining whether Black and White teenagers report having ever been pregnant. Data gathered from 1999 to 2006 by the National Center for Health Statistics of the Center for Disease Control and Prevention included 1,580 Black and White females aged 15 to 19 years. Results supported the effects of race and SES, with SES having the stronger effect. However, the effects of race and SES differ when controlling for the state of the economy. No difference between Blacks and Whites was found during better economic times. During 2003-2004, the period of greatest economic stress, race was determined to be the only predictor of teenage pregnancy. In particular, during 2005-2006, the reduction in pregnancy rates for Black minors (15-17 fell below those for White minors within their respective SES categories. Policy implications are discussed in light of these findings.

  2. "What Exactly Is a Black?": Interrogating the Reality of Race in Jean Genet's The Blacks

    Directory of Open Access Journals (Sweden)

    Debby Thompson

    2002-06-01

    Full Text Available On the dedication page of The Blacks , Genet writes "One evening an actor asked me to write a play for an all-black cast. But what exactly is a black? First of all, what's his color?" Prefiguring major issues and paradoxes of African American cultural studies today, The Blacks insists on the very real ways in which the black/white racial binary, like the very concept of race itself, is lived and socially enforced, and at the same time argues that the binary is ultimately a fiction, made real through performative reification. Genet's "clown show," ambiguously reversing the blackface minstrelsy tradition, dramatizes how racial identity can become internalized and naturalized through cultural myths of interracial rape and colonialist narratives of a "heart of darkness," an imaginary site from which "black essence" arises. These racist performance traditions and narratives are so powerful and resilient that attempts to protest them become subtle and unwitting ways of re-creating them. The Blacks' parody of the minstrel tradition to interrogate all racial identity is so permanently suspended in a dialectic of both reinforcing the black/white binary and invalidating it, that the play's strategies present vital paradigms for the study of other and diverse interrogations of racial ontologies.

  3. Clonal Variations in Flower Production at the Anatolian Black Pine (Pinus nigra Arnold.subsp. pallasiana Seed Orchard

    Directory of Open Access Journals (Sweden)

    Murat ERTEKİN, Korhan TUNÇTANER

    2009-01-01

    Full Text Available This study was conducted for three years (2002-2004 in a black pine seed orchard established with 30 clonesoriginating from the forest of Yenice-Bakraz in Bartın, 1990. During the research, the variations between theclones in the seed orchard were determined based on the number of male and female flowers. According to theresults, the average values of flower production in three years at seed orchard showed considerable variations. Itwas determined that the number of the male and female flowers were 817,2 and 99,3 respectively. 62% ofaverage number of male flowers and 49% of female flowers were produced by 10 clones in 3 years. It was alsodetermined that the amount of the flowers for the clones showed significant differences within the years.

  4. Identité et marchandisation : Le cas des black memorabilia et black collectibles Identity and Commodification: The Case of Black Memorabilia and Black Collectibles

    Directory of Open Access Journals (Sweden)

    Eliane Elmaleh

    2009-07-01

    Full Text Available The aim of this article is to raise the issue of the commodification of African American culture, mainly through a certain form of art that has re-emerged with Black memorabilia which paradoxically fit into a black-driven market. However, these items penetrated American culture from 1920 to the 1950s to convey images of black people as lazy, stupid, childlike and happy. This condition of permanent happiness, typified by a broad smile and white teeth, was a fundamental component of this racist and stereotyped imagery. Thus, this article focuses on the thin border between racism and the denunciation of racism, commodification and denunciation of commodification, art and its by-products being always co-opted in the specific logic of private productivity.

  5. Black Girl Cartography: Black Girlhood and Place-Making in Education Research

    Science.gov (United States)

    Butler, Tamara T.

    2018-01-01

    Drawing on research in education, Black Girlhood studies, and conversations connected to girlhood and cartography, this chapter calls for transdisciplinary analyses of Black girls' sociocultural and geopolitical locations in education research. In reviewing education research documenting the practices and interrogating the experiences of Black…

  6. Axion-dilation black holes

    International Nuclear Information System (INIS)

    Kallosh, R.

    1993-01-01

    In this talk some essential features of stringy black holes are described. The author considers charged U(1) and U(1) x U(1) four-dimensional axion-dilaton black holes. The Hawking temperature and the entropy of all solutions are shown to be simple functions of the squares of supercharges, defining the positivity bounds. Spherically symmetric and multi black hole solutions are presented. The extreme solutions with zero entropy (holons) represent a ground state of the theory and are characterized by elementary dilaton, axion, electric, and magnetic charges. The attractive gravitational and axion-dilaton force is balanced by the repulsive electromagnetic force. The author discusses the possibility of splitting of nearly extreme black holes. 11 refs

  7. Black History, Inc! Investigating the Production of Black History through Walmart's Corporate Web Site

    Science.gov (United States)

    King, LaGarrett J.; Brown, Anthony L.

    2012-01-01

    Social and public sites are becoming a popular medium for intellectual consumption of Black history. Given the educational climate in which many students' exposure to Black history may come from outside of schools, the authors examine how Walmart's Black History Month Web site produced simplistic and safe narratives about African American history.

  8. What Can We Learn About Black-Hole Formation from Black-Hole X-ray Binaries?

    NARCIS (Netherlands)

    Nelemans, G.A.

    2007-01-01

    I discuss the effect of the formation of a black hole on a (close) binary and show some of the current constraints that the observed properties of black hole X-ray binaries put on the formation of black holes. In particular, I discuss the evidence for and against asymmetric kicks imparted on the

  9. Why Are Black Employers More Likely Than White Employers To Hire Blacks? Discussion Paper.

    Science.gov (United States)

    Stoll, Michael A.; Raphael, Steven; Holzer, Harry J.

    This study investigated why black employers tend to hire blacks at higher rates than do white employers and examined individual steps in the hiring process, the role of the hiring agent's race, and the degree to which variation in black application rates related to differences in observable characteristics, such as an establishment's physical…

  10. Cancer incidence profile in sub-Saharan African-born blacks in the United States: Similarities and differences with US-born non-Hispanic blacks.

    Science.gov (United States)

    Medhanie, Genet A; Fedewa, Stacey A; Adissu, Hibret; DeSantis, Carol E; Siegel, Rebecca L; Jemal, Ahmedin

    2017-08-15

    Sub-Saharan African-born blacks (ABs) are one of the fastest-growing populations in the United States. However, to the authors' knowledge, data regarding the cancer burden in this group are lacking, which would inform targeted cancer prevention and control. The authors calculated age-standardized proportional incidence ratios (PIRs) comparing the frequency of the top 15 cancers in ABs with that of US-born non-Hispanic blacks (USBs) by sex and region of birth using incidence data for 2000 through 2012 from the Surveillance, Epidemiology, and End Results (SEER 17) program. Compared with USBs, ABs had significantly higher PIRs of infection-related cancers (liver, stomach, and Kaposi sarcoma), blood cancers (leukemia and non-Hodgkin lymphoma), prostate cancer, and thyroid cancers (females only). For example, the PIR for Kaposi sarcoma in AB versus USB women was 12.06 (95% confidence interval [95% CI], 5.23-18.90). In contrast, ABs had lower PIRs for smoking-related and colorectal cancers (eg, for lung cancer among men, the PIR was 0.30 [95% CI, 0.27-0.34]). Furthermore, cancer occurrence in ABs versus USBs varied by region of birth. For example, the higher PIRs for liver cancer noted among male ABs (PIR, 3.57; 95% CI, 1.79-5.35) and for thyroid cancer in female ABs (PIR, 3.03; 95% CI, 2.03-4.02) were confined to Eastern African-born blacks, whereas the higher PIR for prostate cancer (PIR, 1.90; 95% CI, 1.78, 2.02) was confined to Western African-born blacks. The cancer incidence profile of ABs is different from that of USBs and varies by region of birth, suggesting differences in environmental, cultural, social, and genetic factors. The findings of the current study could stimulate etiologic research and help to inform targeted interventions. Cancer 2017;123:3116-24. © 2017 American Cancer Society. © 2017 American Cancer Society.

  11. Black holes and the multiverse

    International Nuclear Information System (INIS)

    Garriga, Jaume; Vilenkin, Alexander; Zhang, Jun

    2016-01-01

    Vacuum bubbles may nucleate and expand during the inflationary epoch in the early universe. After inflation ends, the bubbles quickly dissipate their kinetic energy; they come to rest with respect to the Hubble flow and eventually form black holes. The fate of the bubble itself depends on the resulting black hole mass. If the mass is smaller than a certain critical value, the bubble collapses to a singularity. Otherwise, the bubble interior inflates, forming a baby universe, which is connected to the exterior FRW region by a wormhole. A similar black hole formation mechanism operates for spherical domain walls nucleating during inflation. As an illustrative example, we studied the black hole mass spectrum in the domain wall scenario, assuming that domain walls interact with matter only gravitationally. Our results indicate that, depending on the model parameters, black holes produced in this scenario can have significant astrophysical effects and can even serve as dark matter or as seeds for supermassive black holes. The mechanism of black hole formation described in this paper is very generic and has important implications for the global structure of the universe. Baby universes inside super-critical black holes inflate eternally and nucleate bubbles of all vacua allowed by the underlying particle physics. The resulting multiverse has a very non-trivial spacetime structure, with a multitude of eternally inflating regions connected by wormholes. If a black hole population with the predicted mass spectrum is discovered, it could be regarded as evidence for inflation and for the existence of a multiverse

  12. Black holes and the multiverse

    Energy Technology Data Exchange (ETDEWEB)

    Garriga, Jaume [Departament de Fisica Fonamental i Institut de Ciencies del Cosmos, Universitat de Barcelona, Marti i Franques, 1, Barcelona, 08028 Spain (Spain); Vilenkin, Alexander; Zhang, Jun, E-mail: jaume.garriga@ub.edu, E-mail: vilenkin@cosmos.phy.tufts.edu, E-mail: jun.zhang@tufts.edu [Institute of Cosmology, Tufts University, 574 Boston Ave, Medford, MA, 02155 (United States)

    2016-02-01

    Vacuum bubbles may nucleate and expand during the inflationary epoch in the early universe. After inflation ends, the bubbles quickly dissipate their kinetic energy; they come to rest with respect to the Hubble flow and eventually form black holes. The fate of the bubble itself depends on the resulting black hole mass. If the mass is smaller than a certain critical value, the bubble collapses to a singularity. Otherwise, the bubble interior inflates, forming a baby universe, which is connected to the exterior FRW region by a wormhole. A similar black hole formation mechanism operates for spherical domain walls nucleating during inflation. As an illustrative example, we studied the black hole mass spectrum in the domain wall scenario, assuming that domain walls interact with matter only gravitationally. Our results indicate that, depending on the model parameters, black holes produced in this scenario can have significant astrophysical effects and can even serve as dark matter or as seeds for supermassive black holes. The mechanism of black hole formation described in this paper is very generic and has important implications for the global structure of the universe. Baby universes inside super-critical black holes inflate eternally and nucleate bubbles of all vacua allowed by the underlying particle physics. The resulting multiverse has a very non-trivial spacetime structure, with a multitude of eternally inflating regions connected by wormholes. If a black hole population with the predicted mass spectrum is discovered, it could be regarded as evidence for inflation and for the existence of a multiverse.

  13. Predictors of Faculty-Student Engagement for Black Men in Urban Community Colleges: An Investigation of the Community College Survey of Men

    Science.gov (United States)

    Wood, J. Luke; Newman, Christopher B.

    2017-01-01

    This research focuses on factors predicting faculty-student engagement for Black male collegians. In this study, the authors investigated whether students' perceptions of racial/gender stereotypes had a moderating effect on the determinants of engagement with faculty. The sample population was derived from 16 urban community colleges located…

  14. Super-horizon primordial black holes

    International Nuclear Information System (INIS)

    Harada, Tomohiro; Carr, B.J.

    2005-01-01

    We discuss a new class of solutions to the Einstein equations which describe a primordial black hole (PBH) in a flat Friedmann background. Such solutions arise if a Schwarzschild black hole is patched onto a Friedmann background via a transition region. They are possible providing the black hole event horizon is larger than the cosmological apparent horizon. Such solutions have a number of strange features. In particular, one has to define the black hole and cosmological horizons carefully and one then finds that the mass contained within the black hole event horizon decreases when the black hole is larger than the Friedmann cosmological apparent horizon, although its area always increases. These solutions involve two distinct future null infinities and are interpreted as the conversion of a white hole into a black hole. Although such solutions may not form from gravitational collapse in the same way as standard PBHs, there is nothing unphysical about them, since all energy and causality conditions are satisfied. Their conformal diagram is a natural amalgamation of the Kruskal diagram for the extended Schwarzschild solution and the conformal diagram for a black hole in a flat Friedmann background. In this paper, such solutions are obtained numerically for a spherically symmetric universe containing a massless scalar field, but it is likely that they exist for more general matter fields and less symmetric systems

  15. Male resource defense mating system in primates? An experimental test in wild capuchin monkeys.

    Directory of Open Access Journals (Sweden)

    Barbara Tiddi

    Full Text Available Ecological models of mating systems provide a theoretical framework to predict the effect of the defendability of both breeding resources and mating partners on mating patterns. In resource-based mating systems, male control over breeding resources is tightly linked to female mating preference. To date, few field studies have experimentally investigated the relationship between male resource control and female mating preference in mammals due to difficulties in manipulating ecological factors (e.g., food contestability. We tested the within-group male resource defense hypothesis experimentally in a wild population of black capuchin monkeys (Sapajus nigritus in Iguazú National Park, Argentina. Sapajus spp. represent an ideal study model as, in contrast to most primates, they have been previously argued to be characterized by female mate choice and a resource-based mating system in which within-group resource monopolization by high-ranking males drives female mating preference for those males. Here, we examined whether females (N = 12 showed a weaker preference for alpha males during mating seasons in which food distribution was experimentally manipulated to be less defendable relative to those in which it was highly defendable. Results did not support the within-group male resource defense hypothesis, as female sexual preferences for alpha males did not vary based on food defendability. We discuss possible reasons for our results, including the possibility of other direct and indirect benefits females receive in exercising mate choice, the potential lack of tolerance over food directed towards females by alpha males, and phylogenetic constraints.

  16. When Supermassive Black Holes Wander

    Science.gov (United States)

    Kohler, Susanna

    2018-05-01

    Are supermassive black holes found only at the centers of galaxies? Definitely not, according to a new study in fact, galaxies like the Milky Way may harbor several such monsters wandering through their midst.Collecting Black Holes Through MergersIts generally believed that galaxies are built up hierarchically, growing in size through repeated mergers over time. Each galaxy in a major merger likely hosts a supermassive black hole a black hole of millions to billions of times the mass of the Sun at its center. When a pair of galaxies merges, their supermassive black holes will often sink to the center of the merger via a process known as dynamical friction. There the supermassive black holes themselves will eventually merge in a burst of gravitational waves.Spatial distribution and velocities of wandering supermassive black holes in three of the authors simulated galaxies, shown in edge-on (left) and face-on (right) views of the galaxy disks. Click for a closer look. [Tremmel et al. 2018]But if a galaxy the size of the Milky Way was built through a history of many major galactic mergers, are we sure that all its accumulated supermassive black holes eventually merged at the galactic center? A new study suggests that some of these giants might have escaped such a fate and they now wander unseen on wide orbits through their galaxies.Black Holes in an Evolving UniverseLed by Michael Tremmel (Yale Center for Astronomy Astrophysics), a team of scientists has used data from a large-scale cosmological simulation, Romulus25, to explore the possibility of wandering supermassive black holes. The Romulus simulations are uniquely suited to track the formation and subsequent orbital motion of supermassive black holes as galactic halos are built up through mergers over the history of the universe.From these simulations, Tremmel and collaborators find an end total of 316 supermassive black holes residing within the bounds of 26 Milky-Way-mass halos. Of these, roughly a third are

  17. Black powder in gas pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Sherik, Abdelmounam [Saudi Aramco, Dhahran (Saudi Arabia)

    2009-07-01

    Despite its common occurrence in the gas industry, black powder is a problem that is not well understood across the industry, in terms of its chemical and physical properties, source, formation, prevention or management of its impacts. In order to prevent or effectively manage the impacts of black powder, it is essential to have knowledge of its chemical and physical properties, formation mechanisms and sources. The present paper is divided into three parts. The first part of this paper is a synopsis of published literature. The second part reviews the recent laboratory and field work conducted at Saudi Aramco Research and Development Center to determine the compositions, properties, sources and formation mechanisms of black powder in gas transmission systems. Microhardness, nano-indentation, X-ray Diffraction (XRD), X-ray Fluorescence (XRF) and Scanning Electron Microscopy (SEM) techniques were used to analyze a large number of black powder samples collected from the field. Our findings showed that black powder is generated inside pipelines due to internal corrosion and that the composition of black powder is dependent on the composition of transported gas. The final part presents a summary and brief discussion of various black powder management methods. (author)

  18. Environmental enrichment affects adrenocortical stress responses in the endangered black-footed ferret

    Science.gov (United States)

    Poessel, S.A.; Biggins, D.E.; Santymire, R.M.; Livieri, T.M.; Crooks, K.R.; Angeloni, L.

    2011-01-01

    Potential stressors of wildlife living in captivity, such as artificial living conditions and frequent human contact, may lead to a higher occurrence of disease and reduced reproductive function. One successful method used by wildlife managers to improve general well-being is the provision of environmental enrichment, which is the practice of providing animals under managed care with environmental stimuli. The black-footed ferret (Mustela nigripes) is a highly-endangered carnivore species that was rescued from extinction by removal of the last remaining individuals from the wild to begin an ex situ breeding program. Our goal was to examine the effect of environmental enrichment on adrenocortical activity in ferrets by monitoring fecal glucocorticoid metabolites (FGM). Results demonstrated that enrichment lowered FGM in juvenile male ferrets, while increasing it in adult females; enrichment had no effect on FGM in juvenile females and adult males. These results correspond with our findings that juvenile males interacted more with the enrichment items than did adult females. However, we did not detect an impact of FGM on the incidence of disease or on the ability of ferrets to become reproductive during the following breeding season. We conclude that an environmental enrichment program could benefit captive juvenile male ferrets by reducing adrenocortical activity. ?? 2011 Elsevier Inc.

  19. Anyon black holes

    Science.gov (United States)

    Aghaei Abchouyeh, Maryam; Mirza, Behrouz; Karimi Takrami, Moein; Younesizadeh, Younes

    2018-05-01

    We propose a correspondence between an Anyon Van der Waals fluid and a (2 + 1) dimensional AdS black hole. Anyons are particles with intermediate statistics that interpolates between a Fermi-Dirac statistics and a Bose-Einstein one. A parameter α (0 quasi Fermi-Dirac statistics for α >αc, but a quasi Bose-Einstein statistics for α quasi Bose-Einstein statistics. For α >αc and a range of values of the cosmological constant, there is, however, no event horizon so there is no black hole solution. Thus, for these values of cosmological constants, the AdS Anyon Van der Waals black holes have only quasi Bose-Einstein statistics.

  20. Black-hole driven winds

    International Nuclear Information System (INIS)

    Punsly, B.M.

    1988-01-01

    This dissertation is a study of the physical mechanism that allows a large scale magnetic field to torque a rapidly rotating, supermassive black hole. This is an interesting problem as it has been conjectured that rapidly rotating black holes are the central engines that power the observed extragalactic double radio sources. Axisymmetric solutions of the curved space-time version of Maxwell's equations in the vacuum do not torque black holes. Plasma must be introduced for the hole to mechanically couple to the field. The dynamical aspect of rotating black holes that couples the magnetic field to the hole is the following. A rotating black hole forces the external geometry of space-time to rotate (the dragging of inertial frames). Inside of the stationary limit surface, the ergosphere, all physical particle trajectories must appear to rotate in the same direction as the black hole as viewed by the stationary observers at asymptotic infinity. In the text, it is demonstrated how plasma that is created on field lines that thread both the ergosphere and the equatorial plane will be pulled by gravity toward the equator. By the aforementioned properties of the ergosphere, the disk must rotate. Consequently, the disk acts like a unipolar generator. It drives a global current system that supports the toroidal magnetic field in an outgoing, magnetically dominated wind. This wind carries energy (mainly in the form of Poynting flux) and angular momentum towards infinity. The spin down of the black hole is the ultimate source of this energy and angular momentum flux

  1. ULTRAMASSIVE BLACK HOLE COALESCENCE

    International Nuclear Information System (INIS)

    Khan, Fazeel Mahmood; Holley-Bockelmann, Kelly; Berczik, Peter

    2015-01-01

    Although supermassive black holes (SMBHs) correlate well with their host galaxies, there is an emerging view that outliers exist. Henize 2-10, NGC 4889, and NGC 1277 are examples of SMBHs at least an order of magnitude more massive than their host galaxy suggests. The dynamical effects of such ultramassive central black holes is unclear. Here, we perform direct N-body simulations of mergers of galactic nuclei where one black hole is ultramassive to study the evolution of the remnant and the black hole dynamics in this extreme regime. We find that the merger remnant is axisymmetric near the center, while near the large SMBH influence radius, the galaxy is triaxial. The SMBH separation shrinks rapidly due to dynamical friction, and quickly forms a binary black hole; if we scale our model to the most massive estimate for the NGC 1277 black hole, for example, the timescale for the SMBH separation to shrink from nearly a kiloparsec to less than a parsec is roughly 10 Myr. By the time the SMBHs form a hard binary, gravitational wave emission dominates, and the black holes coalesce in a mere few Myr. Curiously, these extremely massive binaries appear to nearly bypass the three-body scattering evolutionary phase. Our study suggests that in this extreme case, SMBH coalescence is governed by dynamical friction followed nearly directly by gravitational wave emission, resulting in a rapid and efficient SMBH coalescence timescale. We discuss the implications for gravitational wave event rates and hypervelocity star production

  2. "Iron-Clad" Evidence For Spinning Black Hole

    Science.gov (United States)

    2003-09-01

    Telltale X-rays from iron may reveal if black holes are spinning or not, according to astronomers using NASA's Chandra X-ray Observatory and the European Space Agency's XMM-Newton Observatory. The gas flows and bizarre gravitational effects observed near stellar black holes are similar to those seen around supermassive black holes. Stellar black holes, in effect, are convenient `scale models' of their much larger cousins. Black holes come in at least two different sizes. Stellar black holes are between five and 20 times the mass of the Sun. At the other end of the size scale, supermassive black holes contain millions or billions times the mass of our Sun. The Milky Way contains both a supermassive black hole at its center, as well as a number of stellar black holes sprinkled throughout the Galaxy. At a press conference at the "Four Years of Chandra" symposium in Huntsville, Ala., Jon Miller of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. discussed recent results on the X-ray spectra, or distribution of X-rays with energy, from the iron atoms in gas around three stellar black holes in the Milky Way. "Discovering the high degree of correspondence between stellar and supermassive black holes is a real breakthrough," said Miller. "Because stellar black holes are smaller, everything happens about a million times faster, so they can be used as a test-bed for theories of how spinning black holes affect the space and matter around them." X-rays from a stellar black hole are produced when gas from a nearby companion star is heated to tens of millions of degrees as it swirls toward the black hole. Iron atoms in this gas produce distinctive X-ray signals that can be used to study the orbits of particles around the black hole. For example, the gravity of a black hole can shift the X-rays to lower energies. "The latest work provides the most precise measurements yet of the X-ray spectra for stellar black holes," said Miller. "These data help rule out

  3. Protecting Black Girls

    Science.gov (United States)

    Morris, Monique W.

    2016-01-01

    Statistics show that black girls in U.S. K-12 public schools are overrepresented among students who face disciplinary approaches (such as suspensions) that exclude or even criminalize them. Morris explains how black girls face conditions that make them vulnerable to a phenomenon she calls "school to confinement pathways"--conditions like…

  4. Black holes a very short introduction

    CERN Document Server

    Blundell, Katherine

    2015-01-01

    Black holes are a constant source of fascination to many due to their mysterious nature. Black Holes: A Very Short Introduction addresses a variety of questions, including what a black hole actually is, how they are characterized and discovered, and what would happen if you came too close to one. It explains how black holes form and grow—by stealing material that belongs to stars—as well as how many there may be in the Universe. It also explores the large black holes found in the centres of galaxies, and how black holes power quasars and lie behind other spectacular phenomena in the cosmos.

  5. HIV sexual risk behavior among black men who meet other men on the internet for sex.

    Science.gov (United States)

    White, Jaclyn M; Mimiaga, Matthew J; Reisner, Sari L; Mayer, Kenneth H

    2013-06-01

    Using the Internet to meet sexual partners is associated with increased HIV risk behavior, including substance use, sex with multiple or anonymous partners, and unprotected anal sex (UAS), among diverse samples of MSM, yet little is known about Internet use and HIV risk among Black MSM specifically. In 2008, a sample of 197 Black MSM completed an interviewer-administered assessment and voluntary HIV counseling and testing. One fifth of the sample (20 %) reported meeting a sexual partner via the Internet in the past 12 months. Men who met sexual partners over the Internet had significantly more male sex partners (M = 13.44, SD = 20.01) than men who did not meet partners in this manner (M = 4.11, SD = 4.14, p Internet, identifying as gay, and lower knowledge about HIV transmission. These findings highlight the unique HIV risk behaviors among Black MSM meeting sexual partners via the Internet and warrant tailoring of prevention activities to address the specific behaviors and social influences that may contribute to increased HIV spread among this population.

  6. A study on toxicity of gasoline and GM-10 on liver of mice and it's amelioration by black tea extract.

    Science.gov (United States)

    Verma, Ramtej Jayram; Dave, Manjeet; Mathuria, Neeta

    2008-01-01

    The aim of present study is to investigate the ameliorative effect of black tea extract on gasoline and GM-10 induced toxicity in liver of mice. Eighty healthy male mice weighing 38-40 g approximately were divided into eight groups which included untreated control and various treated groups. Mice were treated with Gasoline 462 mg/kg/day and GM-10 low dose (206 mg/kg/day) and high dose (412 mg/kg/day) subcutaneously for 30 days. Black tea extract was given as 2 g/100 mL drinking water (2% w/v) instead of pure drinking water. All the animals were sacrificed on 31st day by cervical dislocation and livers were isolated and weighed. Parameters such as lipid peroxidation, catalase, superoxide dismutase, glutathione peroxidase, glutathione and total ascorbic acid were studied. The results revealed dose-dependent toxicity of gasoline and GM-10 on liver. Administration of black tea extract ameliorates this toxicity of gasoline and GM-10 in liver of mice. This proves the effective ameliorative effect of black tea extract.

  7. Dye-sensitized solar cells fabricated with black raspberry, black carrot and rosella juice

    Science.gov (United States)

    Tekerek, S.; Kudret, A.; Alver, Ü.

    2011-10-01

    In this work, dye sensitized solar cells (DSSC's) were constructed from black raspberry ( Rubus Ideaus), black carrot ( Daucuscarota L.) and rosella juice ( Hibiscus Sabdariffa L.). In order to fabricate a DSSC the fluorine-doped tin (IV) oxide (FTO) thin films obtained by using spray pyrolysis technique were used as a substrate. TiO2 films on FTO layers were prepared by doctor-blading technique. Platinum-coated counter electrode and liquid Iodide/Iodine electrolyte solution were used to fabricate DSSC's. The efficiencies of solar cells produced with black carrot, rosella and black raspberry juice were calculated as 0.25%, 0.16% and 0.16% respectively, under a sunny day in Kahramanmaraş-Turkey.

  8. Familial Influences on Poverty Among Young Children in Black Immigrant, U.S.-born Black, and Nonblack Immigrant Families

    Science.gov (United States)

    Thomas, Kevin J. A.

    2014-01-01

    This study examines how familial contexts affect poverty disparities between the children of immigrant and U.S.-born blacks, and among black and nonblack children of immigrants. Despite lower gross child poverty rates in immigrant than in U.S.-born black families, accounting for differences in family structure reveals that child poverty risks among blacks are highest in single-parent black immigrant families. In addition, within two-parent immigrant families, child poverty declines associated with increasing assimilation are greater than the respective declines in single-parent families. The heads of black immigrant households have more schooling than those of native-black households. However, increased schooling has a weaker negative association with child poverty among the former than among the latter. In terms of racial disparities among the children of immigrants, poverty rates are higher among black than nonblack children. This black disadvantage is, however, driven by the outcomes of first-generation children of African and Hispanic-black immigrants. The results also show that although children in refugee families face elevated poverty risks, these risks are higher among black than among nonblack children of refugees. In addition, the poverty-reducing impact associated with having an English-proficient household head is about three times lower among black children of immigrants than among non-Hispanic white children of immigrants. PMID:21491186

  9. Graft-copolymerization onto carbon black

    International Nuclear Information System (INIS)

    Nakase, Yoshiaki; Nishii, Masanobu; Kijima, Toshiyuki; Kato, Hiroshi.

    1988-07-01

    Radiation-induced graft copolymerization of vinyl monomer onto carbon black was performed. During the γ-ray- and electron beam-induced polymerization (In-source), or the electron beam post-polymerization, the graft-copolymerization behavior was affected by the kinds of both carbon blacks and monomers, i.e. the smaller the size of carbon black particles, the higher the apparent grafted fraction. Homopolymer in the grafted carbon black samples was washed out by the solvent of the polymer, and the extracted polymer seemed to be dimer or trimer of the used monomer. In the case of the post-polymerization with the pre-irradiation doses of 50 Mrad, homopolymer was hardly observed. The polymer sheets of plastics or rubbers with grafted carbon black had an electrical conductivity unalterable considerably by the heating cycles. The particles of grafted carbon black in the sheet might be kept much more at the surface layer within 100 nm depth than at the inner layer. (author)

  10. Particle creation by black holes

    International Nuclear Information System (INIS)

    Hawking, S.W.

    1975-01-01

    In the classical theory black holes can only absorb and not emit particles. However it is shown that quantum mechanical effects cause black holes to create and emit particles. This thermal emission leads to a slow decrease in the mass of the black hole and to its eventual disappearance: any primordial black hole of mass less than about 10 15 g would have evaporated by now. Although these quantum effects violate the classical law that the area of the event horizon of a black hole cannot decrease, there remains a Generalized Second Law: S + 1/4 A never decreases where S is the entropy of matter outside black holes and A is the sum of the surface areas of the event horizons. This shows that gravitational collapse converts the baryons and leptons in the collapsing body into entropy. It is tempting to speculate that this might be the reason why the Universe contains so much entropy per baryon. (orig.) [de

  11. Black Hole's 1/N Hair

    CERN Document Server

    Dvali, Gia

    2013-01-01

    According to the standard view classically black holes carry no hair, whereas quantum hair is at best exponentially weak. We show that suppression of hair is an artifact of the semi-classical treatment and that in the quantum picture hair appears as an inverse mass-square effect. Such hair is predicted in the microscopic quantum description in which a black hole represents a self-sustained leaky Bose-condensate of N soft gravitons. In this picture the Hawking radiation is the quantum depletion of the condensate. Within this picture we show that quantum black hole physics is fully compatible with continuous global symmetries and that global hair appears with the strength B/N, where B is the global charge swallowed by the black hole. For large charge this hair has dramatic effect on black hole dynamics. Our findings can have interesting astrophysical consequences, such as existence of black holes with large detectable baryonic and leptonic numbers.

  12. Brain nonapeptide and gonadal steroid responses to deprivation of heterosexual contact in the black molly

    OpenAIRE

    Kulczykowska, Ewa; Kalamarz-Kubiak, Hanna; Nietrzeba, Marta; Gozdowska, Magdalena

    2014-01-01

    ABSTRACT Fish may respond to different social situations with changes in both physiology and behaviour. A unique feature of fish is that social interactions between males and females strongly affect the sexual characteristics of individuals. Here we provide the first insight into the endocrine background of two phenomena that occur in mono-sex groups of the black molly (Poecilia sphenops): masculinization in females and same-sex sexual behaviour, manifested by gonopodial displays towards same...

  13. Shaping Globular Clusters with Black Holes

    Science.gov (United States)

    Kohler, Susanna

    2018-03-01

    How many black holes lurk within the dense environments of globular clusters, and how do these powerful objects shape the properties of the cluster around them? One such cluster, NGC 3201, is now helping us to answer these questions.Hunting Stellar-Mass Black HolesSince the detection of merging black-hole binaries by the Laser Interferometer Gravitational-Wave Observatory (LIGO), the dense environments of globular clusters have received increasing attention as potential birthplaces of these compact binary systems.The central region of the globular star cluster NGC 3201, as viewed by Hubble. The black hole is in orbit with the star marked by the blue circle. [NASA/ESA]In addition, more and more stellar-mass black-hole candidates have been observed within globular clusters, lurking in binary pairs with luminous, non-compact companions. The most recent of these detections, found in the globular cluster NGC 3201, stands alone as the first stellar-mass black hole candidate discovered via radial velocity observations: the black holes main-sequence companion gave away its presence via a telltale wobble.Now a team of scientists led by Kyle Kremer (CIERA and Northwestern University) is using models of this system to better understand the impact that black holes might have on their host clusters.A Model ClusterThe relationship between black holes and their host clusters is complicated. Though the cluster environment can determine the dynamical evolution of the black holes, the retention rate of black holes in a globular cluster (i.e., how many remain in the cluster when they are born as supernovae, rather than being kicked out during the explosion) influences how the host cluster evolves.Kremer and collaborators track this complex relationship by modeling the evolution of a cluster similar to NGC 3201 with a Monte Carlo code. The code incorporates physics relevant to the evolution of black holes and black-hole binaries in globular clusters, such as two-body relaxation

  14. Stability of squashed Kaluza-Klein black holes

    International Nuclear Information System (INIS)

    Kimura, Masashi; Ishihara, Hideki; Murata, Keiju; Soda, Jiro

    2008-01-01

    The stability of squashed Kaluza-Klein black holes is studied. The squashed Kaluza-Klein black hole looks like a five-dimensional black hole in the vicinity of horizon and looks like a four-dimensional Minkowski spacetime with a circle at infinity. In this sense, squashed Kaluza-Klein black holes can be regarded as black holes in the Kaluza-Klein spacetimes. Using the symmetry of squashed Kaluza-Klein black holes, SU(2)xU(1)≅U(2), we obtain master equations for a part of the metric perturbations relevant to the stability. The analysis based on the master equations gives strong evidence for the stability of squashed Kaluza-Klein black holes. Hence, the squashed Kaluza-Klein black holes deserve to be taken seriously as realistic black holes in the Kaluza-Klein spacetime.

  15. Prevalence of Toxoplasma gondii infections in Pennsylvania black bears, Ursus americanus.

    Science.gov (United States)

    Briscoe, N; Humphreys, J G; Dubey, J P

    1993-10-01

    Serum samples from 665 hunter-killed black bears killed in 1989 to 1992 throughout Pennsylvania (USA) were tested for Toxoplasma gondii antibodies by the agglutination test in dilutions of 1:25, 1:50, and 1:500. Toxoplasma gondii antibodies were found in 535 of 665 (80%) bears. Considering the highest dilutions at which antibodies were detected, prevalences were 10% at 1:25, 37% at 1:50 and 33% at 1:500. No significant difference in antibody prevalence was found between males (79%) and females (80%), but a significant difference was found between juvenile (65%) and adult (83%) bears.

  16. Queering Black Racial Identity Development

    Science.gov (United States)

    Johnson, Alandis A.; Quaye, Stephen John

    2017-01-01

    We used queer theory to encourage readers to think differently about previous theories about Black racial identity development. Queer theory facilitates new and deeper understandings of how Black people develop their racial identities, prompting more fluidity and nuance. Specifically, we present a queered model of Black racial identity development…

  17. A Typology of Black Leadership.

    Science.gov (United States)

    Tryman, Donald L.

    1977-01-01

    A leadership typology is developed which describes the relationship of Black leadership styles to the Black masses. The role that such leadership plays in the political integration of Blacks as an ethnic group is analyzed. Four authority types are discussed: traditional brokerage, cultural nationalist, religious nationalist, and faddist…

  18. Black p-branes versus black holes in non-asymptotically flat Einstein-Yang-Mills theory

    Science.gov (United States)

    Habib Mazharimousavi, S.; Halilsoy, M.

    2016-09-01

    We present a class of non-asymptotically flat (NAF) charged black p-branes (BpB) with p-compact dimensions in higher-dimensional Einstein-Yang-Mills theory. Asymptotically the NAF structure manifests itself as an anti-de sitter spacetime. We determine the total mass/energy enclosed in a thin shell located outside the event horizon. By comparing the entropies of BpB with those of black holes in the same dimensions we derive transition criteria between the two types of black objects. Given certain conditions satisfied, our analysis shows that BpB can be considered excited states of black holes. An event horizon r+ versus charge square Q2 plot for the BpB reveals such a transition where r+ is related to the horizon radius rh of the black hole (BH) both with the common charge Q.

  19. The search for black holes

    International Nuclear Information System (INIS)

    Torn, K.

    1976-01-01

    Conceivable experimental investigations to prove the existence of black holes are discussed. Double system with a black hole turning around a star-satellite are in the spotlight. X-radiation emmited by such systems and resulting from accretion of the stellar gas by a black hole, and the gas heating when falling on the black hole might prove the model suggested. A source of strong X-radiation observed in the Cygnus star cluster and referred to as Cygnus X-1 may be thus identified as a black hole. Direct registration of short X-ray pulses with msec intervals might prove the suggestion. The lack of appropriate astrophysic facilities is pointed out to be the major difficulty on the way of experimental verifications

  20. Nonextremal stringy black hole

    International Nuclear Information System (INIS)

    Suzuki, K.

    1997-01-01

    We construct a four-dimensional BPS saturated heterotic string solution from the Taub-NUT solution. It is a nonextremal black hole solution since its Euler number is nonzero. We evaluate its black hole entropy semiclassically. We discuss the relation between the black hole entropy and the degeneracy of string states. The entropy of our string solution can be understood as the microscopic entropy which counts the elementary string states without any complications. copyright 1997 The American Physical Society