Molecular genetic diversity and maternal origin of Chinese black-bone chicken breeds.
Zhu, W Q; Li, H F; Wang, J Y; Shu, J T; Zhu, C H; Song, W T; Song, C; Ji, G G; Liu, H X
2014-04-29
Chinese black-bone chickens are valued for the medicinal properties of their meat in traditional Chinese medicine. We investigated the genetic diversity and systematic evolution of Chinese black-bone chicken breeds. We sequenced the DNA of 520 bp of the mitochondrial cyt b gene of nine Chinese black-bone chicken breeds, including Silky chicken, Jinhu black-bone chicken, Jiangshan black-bone chicken, Yugan black-bone chicken, Wumeng black-bone chicken, Muchuan black-bone chicken, Xingwen black-bone chicken, Dehua black-bone chicken, and Yanjin black-bone chicken. We found 13 haplotypes. Haplotype and nucleotide diversity of the nine black-bone chicken breeds ranged from 0 to 0.78571 and 0.00081 to 0.00399, respectively. Genetic diversity was the richest in Jinhu black-bone chickens and the lowest in Yanjin black-bone chickens. Analysis of phylogenetic trees for all birds constructed based on hyplotypes indicated that the maternal origin of black-bone chickens is predominantly from three subspecies of red jungle fowl. These results provide basic data useful for protection of black-bone chickens and help determine the origin of domestic chickens.
The Power of the Rap: The Black Idiom and the New Black Poetry.
ERIC Educational Resources Information Center
Smitherman, Geneva
Black Arts Literature--of which the New Black Poetry is the most important manifestation--emerged during the past decade as the appropriate artistic counterthrust to Black Power. Rhetoric and shouting aside, this new thrust was, on a very basic level, simply a call to black folks to redefine Blackness and re-evaluate the Black Experience. For the…
For blacks in America, the gap in neighborhood poverty has declined faster than segregation.
Firebaugh, Glenn; Acciai, Francesco
2016-11-22
Black residential segregation has been declining in the United States. That accomplishment rings hollow, however, if blacks continue to live in much poorer neighborhoods than other Americans. This study uses census data for all US metropolitan areas in 1980 and 2010 to compare decline in the neighborhood poverty gap between blacks and other Americans with decline in the residential segregation of blacks. We find that both declines resulted primarily from narrowing differences between blacks and whites as opposed to narrowing differences between blacks and Hispanics or blacks and Asians. Because black-white differences in neighborhood poverty declined much faster than black-white segregation, the neighborhood poverty disadvantage of blacks declined faster than black segregation-a noteworthy finding because the narrowing of the racial gap in neighborhood poverty for blacks has gone largely unnoticed. Further analysis reveals that the narrowing of the gap was produced by change in both the medians and shapes of the distribution of poverty across the neighborhoods where blacks, whites, Hispanics, and Asians reside.
IMAGES OF BLACK AMERICANS: Then, "Them," and Now, "Obama!"
Fiske, Susan T; Bergsieker, Hilary B; Russell, Ann Marie; Williams, Lyle
2009-01-01
Images of Black Americans are becoming remarkably diverse, enabling Barack Obama to defy simple-minded stereotypes and succeed. Understood through the Stereotype Content Model's demonstrably fundamental trait dimensions of perceived warmth and competence, images of Black Americans show three relevant patterns. Stereotyping by omission allows non-Blacks to accentuate the positive, excluding any lingering negativity but implying it by its absence; specifically, describing Black Americans as gregarious and passionate suggests warmth but ignores competence and implies its lack. Obama's credentials prevented him from being cast as incompetent, though the experience debate continued. His legendary calm and passionate charisma saved him on the warmth dimension. Social class subtypes for Black Americans differentiate dramatically between low-income Blacks and Black professionals, among both non-Black and Black samples. Obama clearly fit the moderately warm, highly competent Black-professional subtype. Finally, the campaign's events (and nonevents) allowed voter habituation to overcome non-Blacks' automatic emotional vigilance to Black Americans.
Black English and Black Attitudes
ERIC Educational Resources Information Center
Shores, David L.
1974-01-01
Examines attitudes in the Black community towards the topic of Black English and specifically the controversy about the relationship of the speech of Blacks to that of Whites, the distinctive features in the speaking and writing of Black college students, and the attitudes of Black educators. Available from South Atlantic Modern Language…
77 FR 50668 - Proposed Flood Elevation Determinations
Federal Register 2010, 2011, 2012, 2013, 2014
2012-08-22
... County, Texas, and Incorporated Areas. Specifically, it addresses the flooding sources: Black Fork Creek, Black Fork Creek Tributary BF-1, Black Fork Creek Tributary BF-M-1, Black Fork Creek Tributary D, Black Fork Creek Tributary D-1, Black Fork Creek Tributary D-2, Black Fork Creek Tributary D-3, Butler Creek...
The Black Man's Burden: The White Clinician
ERIC Educational Resources Information Center
Wesson, K. Alan
1975-01-01
The stated purpose of this article is to advocate that those dealing with black people and black problems have some appreciable degree of knowledge concerning black culture, black jargon, black behavior, and the black or Afro-American psyche: only then can therapy be seen as satisfying the purposes for which it was initially intended. (Author/JM)
The Crisis in Black and Black.
ERIC Educational Resources Information Center
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…
Can Blacks Be Racists? Black-on-Black Principal Abuse in an Urban School Setting
ERIC Educational Resources Information Center
Khalifa, Muhammad
2015-01-01
This study examines Black student and parental perceptions of exclusionary practices of Black school principals. I ask why students and parents viewed two Black principals as contributing to abusive and exclusionary school environments that marginalized Black students. After a two-year ethnographic study, it was revealed that exclusionary…
In the Absence of Ideology: Blacks in Colonial America and the Modern Black Experience.
ERIC Educational Resources Information Center
Jones, Rhett S.
1988-01-01
The experiences of Whites and Blacks in the American Colonial period were strikingly different. Blacks were committed to Whites' Enlightenment ideology, which did not reflect Black experience. Blacks in the Colonial era were unable to create political structures capable of making sense of the Black experience. (BJV)
Fiske, Susan T.; Bergsieker, Hilary B.; Russell, Ann Marie; Williams, Lyle
2013-01-01
Images of Black Americans are becoming remarkably diverse, enabling Barack Obama to defy simple-minded stereotypes and succeed. Understood through the Stereotype Content Model’s demonstrably fundamental trait dimensions of perceived warmth and competence, images of Black Americans show three relevant patterns. Stereotyping by omission allows non-Blacks to accentuate the positive, excluding any lingering negativity but implying it by its absence; specifically, describing Black Americans as gregarious and passionate suggests warmth but ignores competence and implies its lack. Obama’s credentials prevented him from being cast as incompetent, though the experience debate continued. His legendary calm and passionate charisma saved him on the warmth dimension. Social class subtypes for Black Americans differentiate dramatically between low-income Blacks and Black professionals, among both non-Black and Black samples. Obama clearly fit the moderately warm, highly competent Black-professional subtype. Finally, the campaign’s events (and nonevents) allowed voter habituation to overcome non-Blacks’ automatic emotional vigilance to Black Americans. PMID:24235974
"Be Real Black for Me": Imagining BlackCrit in Education
ERIC Educational Resources Information Center
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,…
Low-mass black holes as the remnants of primordial black hole formation.
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.
Survey of coatings for solar collectors. [ceramic enamels and chromium
NASA Technical Reports Server (NTRS)
Mcdonald, G. E.
1974-01-01
Ceramic enamel is found to be more solar selective, (i.e., has high solar absorptance in combination with low infrared emittance) than organic enamel, but neither is as solar selective as black chrome, black copper, black zinc, or black nickel. Ceramic enamel is matched only by black chrome in durability and wide availability. Ceramic enamel and organic enamel have approximately the same cost, and both are currently slightly lower in cost than black chrome, black copper, or black zinc. Black nickel is relatively unavailable and, because of that, realistic cost comparisons are not possible.
Validity of black hole complementarity in the BTZ black hole
NASA Astrophysics Data System (ADS)
Gim, Yongwan; Kim, Wontae
2018-01-01
Based on the gedanken experiment for black hole complementarity in the Schwarzschild black hole, we calculate the energy required to duplicate information in the BTZ black hole under the assumption of absorbing boundary condition and its dual solution of the black string, respectively, in order to justify the validity of the no-cloning theorem in quantum mechanics. For the BTZ black hole, the required energy for the duplication of information can be made fairly small, whereas for the black string it exceeds the total mass of the black string, although they are related to each other under the dual transformation. So, the duplication of information might be possible in the BTZ black hole in contrast to the case of the black string, so that the no-cloning theorem could be violated for the former case. To save the duplication of information for the BTZ black hole, we perform an improved gedanken experiment by using the local thermodynamic quantities near the horizon rather than those defined at infinity, and show that the no-cloning theorem could be made valid even in the BTZ black hole. We also discuss how this local treatment for the no-cloning theorem can be applied to the black string as well as the Schwarzschild black hole innocuously.
Understanding the New Black Poetry: Black Speech and Black Music as Poetic References.
ERIC Educational Resources Information Center
Henderson, Stephen
Oral tradition, both rural and urban, forms an infrastructure for this anthology, which presents selections of black poetry with an emphasis on the poetry of the sixties. Based on the thesis that the new black poetry's main referents are black speech and black music, the anthology includes examples from the oral tradition of folk sermon,…
O'Connor, L A; Brooks-Gunn, J; Graber, J
2000-09-01
This exploratory research compared Black and White girls' racial preferences as exhibited through their media (music and television) and peer choices. The sample included 140 8- and 9-year-old Black and White girls of various socioeconomic levels. Findings suggested that both Black and White girls have more Black music preferences than White or no-race music preferences. Also, both Black and White girls made more White television program choices than Black or no-race choices. In their peer selections, all girls preferred same-race peers. Black mothers who engaged in racial socialization practices had girls who were more likely to prefer Black music and television to the other categories. Further, Black mothers who promoted more cultural distance and mothers who were poor had girls with more same-race peer preferences.
ERIC Educational Resources Information Center
Journal of Blacks in Higher Education, 2002
2002-01-01
Presents a collection of articles on blacks in higher education, including such topics as: older black students; blacks in academic nursing; black medical school enrollment; blacks in academic psychology; black colleges being ignored by the Rhodes Scholarship Committee; school desegregation in Cambridge, Massachusetts; Louis Farrakhan as a GOP…
ERIC Educational Resources Information Center
Journal of Blacks in Higher Education, 2002
2002-01-01
This collection of articles focuses on such topics as the importance of college education among black business leaders; ranking of black colleges; black student recruitment; black scholars and African American publishing; Blacks in the life sciences; segregation in college sports; black enrollments; affirmative action; and differences in student…
Spectral reflectance properties of black chrome for use as a solar selective coating
NASA Technical Reports Server (NTRS)
Mcdonald, G. E.
1974-01-01
The NASA-Lewis Research Center has determined that a widely available commercially electroplated decorative finish known as black chrome has desirable solar selective properties. Black chrome electroplated coating has high absorbtance in the solar spectrum and low emissivity in the 250 F blackbody thermal spectrum. The spectral reflectance properties of a commercially prepared black chrome on steel have been measured. Values are presented for reflectance of the black chrome, and compared with the reflectance of black paint and with two available samples of black nickel which had been prepared for solar selective properties. The reflectance of black chrome, of the two black nickels, and of black paint integrated over the solar spectrum for air mass 2 were 0.132, 0.123, 0.133, and 0.033, respectively. The reflectance of the black chrome, two black nickels, and of the black paint integrated over the blackbody spectrum for 250 F from 3 to 15 microns are 0.912, 0.934, 0.891, and 0.033, respectively. These reflectance measurements indicate absorptivity-to-emissivity values of 9.8, 13.8, 8.0, and 1.00, respectively.
West, Brooke; Linton, Sabriya; Hunter-Jones, Josalin; Zlotorzynska, Maria; Stall, Ron; Wolfe, Mary E.; Williams, Leslie; Hall, H. Irene; Cleland, Charles; Tempalski, Barbara; Friedman, Samuel R.
2016-01-01
Objectives. We sought to determine whether contextual factors shape injection drug use among Black adolescents and adults. Methods. For this longitudinal study of 95 US metropolitan statistical areas (MSAs), we drew annual MSA-specific estimates of the prevalence of injection drug use (IDU) among Black adolescents and adults in 1993 through 2007 from 3 surveillance databases. We used existing administrative data to measure MSA-level socioeconomic status; criminal justice activities; expenditures on social welfare, health, and policing; and histories of Black uprisings (1960–1969) and urban renewal funding (1949–1974). We regressed Black IDU prevalence on these predictors by using hierarchical linear models. Results. Black IDU prevalence was lower in MSAs with declining Black high-school dropout rates, a history of Black uprisings, higher percentages of Black residents, and, in MSAs where 1992 White income was high, higher 1992 Black income. Incarceration rates were unrelated. Conclusions. Contextual factors shape patterns of drug use among Black individuals. Structural interventions, especially those that improve Black socioeconomic security and political strength, may help reduce IDU among Black adolescents and adults. PMID:26691126
Differences Between Black Youth Who Support the Black Panthers and the NAACP
ERIC Educational Resources Information Center
Levine, Daniel U.; And Others
1973-01-01
This study compares the attitudes of black youth who have a favorable orientation toward the Black Panthers with those of black youth who appear to be oriented toward the NAACP, using data collected in five black segregated high schools. (Author/JM)
Spectral reflectance properties of black chrome for use as a solar selective coating
NASA Technical Reports Server (NTRS)
Mcdonald, G. E.
1974-01-01
The NASA-Lewis Research Center has determined that a widely available commercially electroplated decorative finish known as black chrome has desirable solar selective properties. The spectral reflectance properties of a commercially prepared black chrome on steel were measured. Values are presented for reflectance of the black chrome, and compared with the reflectance of black paint (Nextel) and with two available samples of black nickel which had been prepared for solar selective properties. The reflectance of black chrome, of the two black nickels, and of black paint integrated over the solar spectrum for air mass 2 were 0.132, 0.123, 0.133, and 0.033, respectively. The reflectance of the black chrome, two black nickels, and of the black paint integrated over the blackbody spectrum for 250 F from 3 to 15 microns are 0.912, 0.934, 0.891, and 0.033, respectively. These reflectance measurements indicate absorptivity-to-emissivity values of 9.8, 13.8, 8.0, and 1.00, respectively.
Brooks, Siobhan
2016-12-01
The concept Don't Ask, Don't Tell regarding Black LGBT sexuality in Black communities has been an acceptable form of identity management for Black LGBT people. In other words, Black LGBT people are accepted as long as they are not vocal about their sexuality. However, this is changing with the issue of gay marriage, which is creating a space where Black LGBT people are more open about their gender identity and sexuality in heterosexual Black spaces. This new form of openness allows Black LGBT people to "stay in" their communities, as opposed to coming out. In this article I examine how Black LGBT women in North Philadelphia stay in their communities: being politically active regarding LGBT issues, disengaging from LGBT issues, passing, and educating straight Black people about issues affecting the Black LGBT community. I conclude with implications of staying in and intersectionality among Black heterosexual and LGBT women fighting for social change.
For blacks in America, the gap in neighborhood poverty has declined faster than segregation
Acciai, Francesco
2016-01-01
Black residential segregation has been declining in the United States. That accomplishment rings hollow, however, if blacks continue to live in much poorer neighborhoods than other Americans. This study uses census data for all US metropolitan areas in 1980 and 2010 to compare decline in the neighborhood poverty gap between blacks and other Americans with decline in the residential segregation of blacks. We find that both declines resulted primarily from narrowing differences between blacks and whites as opposed to narrowing differences between blacks and Hispanics or blacks and Asians. Because black–white differences in neighborhood poverty declined much faster than black–white segregation, the neighborhood poverty disadvantage of blacks declined faster than black segregation—a noteworthy finding because the narrowing of the racial gap in neighborhood poverty for blacks has gone largely unnoticed. Further analysis reveals that the narrowing of the gap was produced by change in both the medians and shapes of the distribution of poverty across the neighborhoods where blacks, whites, Hispanics, and Asians reside. PMID:27821759
Huang, Ru-Yue; Chou, Cheng-Chun
2008-09-24
Steamed black soybeans and black soybean koji, a potentially functional food additive, were subjected to heating at 40-100 degrees C for 30 min. It was found that steamed black soybeans and black soybean koji after heating at 80 degrees C or higher generally showed reduced contents of malonylglucoside, acetylglucoside, and aglycone isoflavone and an increased content of beta-glucoside. A lower reduction in malonylglucoside and acetylglucoside isoflavone but greater reduction in aglycone content was noted in steamed black soybeans compared to black soybean koji after a similar heat treatment. After 30 min of heating at 100 degrees C, steamed black soybean retained ca. 90.3 and 83.8%, respectively, of its original malonylglucoside and acetylglucoside isoflavone, compared to lower residuals of 80.9 and 78.8%, respectively, for black soybean koji. In contrast, the heated black soybeans showed an aglycone residual of 68.0%, which is less than the 80.0% noted with the heated black soybean koji.
To Find an Image: Black Films from Uncle Tom to Super Fly.
ERIC Educational Resources Information Center
Murray, James P.
This book surveys the roles of blacks in the film industry. The introduction discusses the question if why there should be a black cinema. The seventeen sections of the book discuss such people and topics as the black actor, movies and life and black people, Sidney Poitier as the black superstar, Diahann Carroll and black female singers in movies,…
Black Women in the Labor Force. Facts on Working Women No. 90-4.
ERIC Educational Resources Information Center
Women's Bureau (DOL), Washington, DC.
During the 1980s, the population of black women aged 16 years and older in the United States increased by 17.2%, and labor force participation for black women increased by 29%. In 1987, black women accounted for 50% of total black employment. The unemployment rate for black teenagers in 1990 was 30% (versus 10.8% for all black women). Labor force…
Ford, Obie
2015-01-01
This research presents an examination of Black gay men and their lived experiences while undergraduates at historically Black colleges and universities (HBCUs). Based on 10 in-depth interviews with self-identified Black gay men, the author presents four emergent themes, which reveal the complex ways in which Black gay men navigate and negotiate the intersections of their multiple identities as related to race, sexual orientation, and gender at HBCUs. The findings of this research have implications for larger discussions of community, Black masculinity, and gay identity in predominantly Black and non-Black contexts.
Framing black boys: parent, teacher, and student narratives of the academic lives of black boys.
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.
Mason, Susan M.; Kaufman, Jay S.; Daniels, Julie L.; Emch, Michael E.; Hogan, Vijaya K.; Savitz, David A.
2013-01-01
Purpose Studies of ethnic density and health in the United States have documented poorer health outcomes in black compared to non-black neighborhoods, but few studies have considered the identities of the non-black populations. Methods New York City birth records from 1995 through 2003 and a spatial measure of ethnic density were used to examine preterm birth risks among non-Hispanic black women associated with non-Hispanic white, Hispanic, Asian, and non-Hispanic black neighborhood densities. Logistic regression models were used to estimate the effect on black preterm birth risks of replacing white neighbors with Hispanic, Asian, and black neighbors. Risk differences were computed for changes from the 10th to the 90th percentiles of ethnic density. Results Increasing Hispanic density was associated with reduced preterm birth risks among non-Hispanic black women, especially if the black women were foreign-born (RD=−19.1 per 1,000 births; 95% CI: −28.6, −9.5). Estimates for increasing Asian density were null. Increasing black density was associated with increasing black preterm birth risk, with a threshold at higher levels of black density. Conclusions The low risks of preterm birth among foreign-born non-Hispanic black women in majority-Hispanic neighborhoods may be related to protective psychosocial or nutritional factors in Hispanic neighborhoods. PMID:21737050
Smoking Cessation among Blacks.
ERIC Educational Resources Information Center
Stotts, R. Craig; And Others
1991-01-01
Lung cancer is a serious health problem among blacks, with a mortality rate of 119 per 100,000 black males, compared to 81 per 100,000 for white males. Smoking cessation efforts are most successful when tailored to the black community, using black community networks and broadcast media for black audiences. (SLD)
What Black Educators are Saying.
ERIC Educational Resources Information Center
Wright, Nathan, Jr., Ed.
Contents of this book are comprised of five groups of articles: Part I. The Black Educator: "Education for black humanism; a way of approaching it," Preston Wilcox; "The new black dimension in our society," Olivia Pearl Stokes; "The black teacher and black Power," Leslie Campbell; and, "The difference," Leslie Campbell. Part II. The White…
ERIC Educational Resources Information Center
Byrd, Donald
1976-01-01
The author states that black music is an expression of the black experience. Counseling engages the experience of the person(s) counseled but ignores an important expressive outlet blacks have used in their struggle for survival. If counselors are to understand black people, they must listen to and understand black music. (Author)
ERIC Educational Resources Information Center
Thomas, Kevin J. A.
2010-01-01
This study examines how familial contexts affect poverty disparities between the children of immigrant and US-born Blacks, and among Black and non-Black children of immigrants. Despite lower gross child poverty rates in immigrant than US-born Black families, accounting for differences in family structure reveals that child poverty risks among…
REVIEWS OF TOPICAL PROBLEMS: Search for black holes
NASA Astrophysics Data System (ADS)
Cherepashchuk, Anatolii M.
2003-04-01
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.
Refinement in black chrome for use as a solar selective coating
NASA Technical Reports Server (NTRS)
Mcdonald, G. E.
1974-01-01
Black chrome is significant as a solar selective coating because the current extensive use of black chrome in the electroplating industry as a durable decorative finish makes black chrome widely available on a commercial scale and potentially low in cost as a solar selective coating. Black-chrome deposits were modified by underplating with dull nickel or by being plated on rough surfaces. Both of these procedures increased the visible absorptance. There was no change in the infrared reflectance for the dull-nickel - black-chrome combination from that reported for the bright-nickel - black-chrome combination. However, the bright-nickel - black-chrome coating plated on rough surfaces indicated a slight decrease in infrared reflectance. As integrated over the solar spectrum for air mass 2, the reflectance of the dull-nickel - black-chrome coating was 0.077, of the bright-nickel - black-chrome coating plated on a 0.75-micron (30-microinch) surface was 0.070, of the bright-nickel - black-chrome coating plated on a 2.5 micron (100-microinch) surface was 0.064. The corresponding values for the bright-nickel - black-chrome coating on a 0.0125-micron (0.5-microinch) surface, two samples of black nickel, and two samples of Nextrel black paint were 0.132, 0.123, 0.133, and 0.033, respectively.
Omonuwa, S. C.
2001-01-01
CONTEXT: Racial disparities in health care between black women and white women may be attributed in part to socioeconomic status and lack of insurance, but also may be due to lack of the dissemination of health information in black communities via black popular magazines. OBJECTIVE: Comparison of the number and type of pharmaceutical advertisements between black-oriented magazines and white-oriented magazines. DESIGN: Descriptive study. SETTING: Morehouse School of Medicine. MAIN OUTCOME MEASURES: Recording of the type and number of over-the-counter and prescription drug advertisements. RESULTS: Five black-oriented magazines (Black Woman, Black Elegance, Essence, Ebony, and Upscale) and 5 white-oriented magazines (Family Circle, Working Mother, Good Housekeeping, Ladies' Home Journal, Women's Day) were evaluated for 3 months from June-August, 2000. White-oriented magazines had four to eight times more pharmaceutical ads than black-oriented magazines. Types of medications advertised in the white-oriented magazines and not the black-oriented magazines were, for example, cholinesterase inhibitors, calcium supplements, COX II-inhibitors, intranasal steroids, anorexiants, proton pump inhibitors, and smoking deterrent agents. Conversely, medications advertised in the black-oriented magazines and not the white-oriented magazines were antiviral agents and oral contraceptives. Pharmaceutical companies gave several reasons for the disparity, including the explanation that their particular company was advertising about HIV in the black community. CONCLUSIONS: A barrier to equitable health care for black women may be a low prioritization for health prevention and health management. This low prioritization or disinterest may be a reflection of the black magazine that she is reading due to the lack of pharmaceutical advertisements in black-oriented magazines. The result of this disinterest of black females may be seen in the increased morbidity and mortality for selected diseases. PMID:11491276
NASA Astrophysics Data System (ADS)
Zhang, Tianxi
2014-01-01
Slightly modifying the standard big bang theory, the author has recently 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, cosmic microwave background radiation, and acceleration 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 study investigates the emissions of dynamic black holes according to the black hole universe model and provides a self-consistent explanation for the observations of gamma ray bursts (GRBs), X-ray flares, and quasars as emissions of dynamic star-like, massive, and supermassive black holes. It is shown that a black hole, when it accretes its ambient matter or merges with other black holes, becomes dynamic. Since the event horizon of a dynamic black hole is broken, the inside hot (or high-frequency) blackbody radiation leaks out. The leakage of the inside hot blackbody radiation leads to a GRB if it is a star-like black hole, an X-ray flare if it is a massive black hole like the one at the center of the Milky Way, or a quasar if it is a supermassive black hole like an active galactic nucleus (AGN). The energy spectra and amount of emissions produced by the dynamic star-like, massive, and supermassive black holes can be consistent with the measurements of GRBs, X-ray flares, and quasars.
Omonuwa, S C
2001-01-01
Racial disparities in health care between black women and white women may be attributed in part to socioeconomic status and lack of insurance, but also may be due to lack of the dissemination of health information in black communities via black popular magazines. Comparison of the number and type of pharmaceutical advertisements between black-oriented magazines and white-oriented magazines. Descriptive study. Morehouse School of Medicine. Recording of the type and number of over-the-counter and prescription drug advertisements. Five black-oriented magazines (Black Woman, Black Elegance, Essence, Ebony, and Upscale) and 5 white-oriented magazines (Family Circle, Working Mother, Good Housekeeping, Ladies' Home Journal, Women's Day) were evaluated for 3 months from June-August, 2000. White-oriented magazines had four to eight times more pharmaceutical ads than black-oriented magazines. Types of medications advertised in the white-oriented magazines and not the black-oriented magazines were, for example, cholinesterase inhibitors, calcium supplements, COX II-inhibitors, intranasal steroids, anorexiants, proton pump inhibitors, and smoking deterrent agents. Conversely, medications advertised in the black-oriented magazines and not the white-oriented magazines were antiviral agents and oral contraceptives. Pharmaceutical companies gave several reasons for the disparity, including the explanation that their particular company was advertising about HIV in the black community. A barrier to equitable health care for black women may be a low prioritization for health prevention and health management. This low prioritization or disinterest may be a reflection of the black magazine that she is reading due to the lack of pharmaceutical advertisements in black-oriented magazines. The result of this disinterest of black females may be seen in the increased morbidity and mortality for selected diseases.
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.
Are LIGO's Black Holes Made from Smaller Black Holes?
NASA Astrophysics Data System (ADS)
Fishbach, Maya; Holz, Daniel; Farr, Ben; LIGO Collaboration
2017-01-01
We consider the hierarchical merger model for the formation of stellar mass black holes (such as the binary black holes observable by LIGO). In the hierarchical merger model, each black hole in a black hole binary is the result of a merger of two lesser black holes from a previous generation, and the previous generation's black holes may themselves be merger products of an even earlier generation. We apply the formulas of Hofmann, Barausse and Rezzolla (2016) to show that if black holes form in this hierarchical merger scenario, their spin magnitudes follow a certain probability distribution. We demonstrate how to compare this spin distribution to LIGO spin measurements in order to constrain the hierarchical merger scenario.
The Black Dentist Workforce in the United States
Mertz, Elizabeth; Calvo, Jean; Wides, Cynthia; Gates, Paul
2017-01-01
Objectives The purpose of this paper is to describe the Black dentist workforce, the practice patterns of providers, and their contributions to oral health care for minority and underserved patients. Methods A national sample survey of underrepresented minority dentists was conducted in 2012 and received a 32.6% response rate for self-reported Black dentists. Data were weighted for selection and response bias to be nationally representative. Descriptive and multivariable statistics were computed to provide a workforce profile of Black dentists. National comparisons are provided from published data. Results Among all Black dentists (weighted n=6,254), 76.6% self-identify as African-American, 13.2% as African, and 10.3% as Afro-Caribbean. The largest share of Black dentists are male, married, heterosexual, born in the U.S. and raised in a medium to large city. One third of Black dentists were the first in their family to graduate from college. Black dentists report higher average educational debt than all dental students, graduates from International Dentist Programs having the greatest debt. Traditional practices (i.e., private practices) dominate, with 67.1% of Black dentists starting out in this setting and 73.5% currently in the setting. Black dentists care for a disproportionate share of Black patients, with an average patient mix that is 44.9% Black. Two in five Black dentists reported their patient pool is made up of more than 50% Black patients. Conclusions The underrepresentation for Black dentists is extraordinary, and the Black dentists that are in practice are shouldering a disproportionate share of dental care for minority and underserved communities. PMID:27966789
On the Charter Question: Black Marxism and Black Nationalism
ERIC Educational Resources Information Center
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…
Black Newspapers: Overlooked Barometers. NCRIEEO Tipsheet, Number 1.
ERIC Educational Resources Information Center
Columbia Univ., New York, NY. National Center for Research and Information on Equal Educational Opportunity.
Black newspapers should not go unnoticed by school administrators, as they too often are. Black people have a long and proud history of intraracial communication. More than 200 "black" periodicals work hard at forming, leading, and interpreting for black communities. No black community is totally dependent upon the standard white-owned and…
The Impatient Press: Placing Black Newspapers in the Ideologies of Black Progress.
ERIC Educational Resources Information Center
Caspari, Genevieve G.
Unlike its white counterpart, the black press has historically exceeded its role of information source. Specialized black media were founded to decry racial conflict and gain civil rights. Only rarely, and secondarily, have black papers achieved commercial success. The purposes of black papers have changed with the society they serve. Ideologies…
Black Boundary Lines: Race, Class and Gender among Black Undergraduate Students
ERIC Educational Resources Information Center
Morales, Erica Marie
2012-01-01
Intra-group differences among Black undergraduate students remain understudied. To gain a more nuanced understanding of Black student life, we must examine how other social locations, like gender and class, connect to the racialized experiences of Black students. This dissertation argues that for Black students, class and gender, along with race,…
"Black Like Me": Reframing Blackness for Decolonial Politics
ERIC Educational Resources Information Center
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,…
The Black Lives Matter Movement and Historically Black Colleges and Universities
ERIC Educational Resources Information Center
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…
Ten Myths, Half-Truths and Misunderstandings About Black History.
ERIC Educational Resources Information Center
Ruffins, Paul
1997-01-01
Common myths and misconceptions about Blacks in American history and evidence that refutes them are presented. Issues addressed include Black enslavement patterns, social status within the Black community based on skin color, the legality of slaves learning to read, resistance to slavery, African influences in modern Black culture, Black names and…
Black string in dRGT massive gravity
NASA Astrophysics Data System (ADS)
Tannukij, Lunchakorn; Wongjun, Pitayuth; Ghosh, Suchant G.
2017-12-01
We present a cylindrically symmetric solution, both charged and uncharged, which is known as a black string solution to the nonlinear ghost-free massive gravity found by de Rham, Gabadadze, and Tolley (dRGT). This "dRGT black string" can be thought of as a generalization of the black string solution found by Lemos. Moreover, the dRGT black string solution includes other classes of black string solution such as the monopole-black string ones since the graviton mass contributes to the global monopole term as well as the cosmological-constant term. To investigate the solution, we compute mass, temperature, and entropy of the dRGT black string. We found that the existence of the graviton mass drastically affects the thermodynamics of the black string. Furthermore, the Hawking-Page phase transition is found to be possible for the dRGT black string as well as the charged dRGT black string. The dRGT black string solution is thermodynamically stable for r>r_c with negative thermodynamical potential and positive heat capacity while it is unstable for r
Black Music: Sound and Feeling for Black Liberation
ERIC Educational Resources Information Center
McClendon, William H.
1976-01-01
Focuses on contemporary black music and the assortment of persons who produce it noting that black music is one area where black people provide their definitions and make their own judgements. (Author/AM)
NASA Astrophysics Data System (ADS)
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.
Stability of squashed Kaluza-Klein black holes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kimura, Masashi; Ishihara, Hideki; Murata, Keiju
2008-03-15
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){approx_equal}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-Kleinmore » black holes deserve to be taken seriously as realistic black holes in the Kaluza-Klein spacetime.« less
Cosmic microwave background radiation of black hole universe
NASA Astrophysics Data System (ADS)
Zhang, T. X.
2010-11-01
Modifying slightly the big bang theory, the author has recently developed a new cosmological model called black hole universe. This new cosmological model is consistent with the Mach principle, Einsteinian general theory of relativity, and observations of the universe. The origin, structure, evolution, and expansion of the black hole universe have been presented in the recent sequence of American Astronomical Society (AAS) meetings and published recently in a scientific journal: Progress in Physics. This paper explains the observed 2.725 K 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 universe with hundred billion-trillions of solar masses. According to the black hole universe model, the observed cosmic microwave background radiation can be explained as the black body radiation of the black hole universe, which can be considered as an ideal black body. When a hot and dense star-like black hole accretes its ambient materials and merges with other black holes, it expands and cools down. A governing equation that expresses the possible thermal history of the black hole universe is derived from the Planck law of black body radiation and radiation energy conservation. The result obtained by solving the governing equation indicates that the radiation temperature of the present universe can be ˜2.725 K if the universe originated from a hot star-like black hole, and is therefore consistent with the observation of the cosmic microwave background radiation. A smaller or younger black hole universe usually cools down faster. The characteristics of the original star-like or supermassive black hole are not critical to the physical properties of the black hole universe at present, because matter and radiation are mainly from the outside space, i.e., the mother universe.
Affirmative action and the Black women in South Africa.
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 to be recognized as already having some knowledge. Resistance to affirmative action needs to be stopped and the thrust of action focused on a liveable place for all. There is a need for multiple approaches which stress education, training, support systems, quotas, legislation, and an end to the bickering over which one works best.
Conformal Field Theory and black hole physics
NASA Astrophysics Data System (ADS)
Sidhu, Steve
2012-01-01
This thesis reviews the use of 2-dimensional conformal field theory applied to gravity, specifically calculating Bekenstein-Hawking entropy of black holes in (2+1) dimensions. A brief review of general relativity, Conformal Field Theory, energy extraction from black holes, and black hole thermodynamics will be given. The Cardy formula, which calculates the entropy of a black hole from the AdS/CFT duality, will be shown to calculate the correct Bekenstein-Hawking entropy of the static and rotating BTZ black holes. The first law of black hole thermodynamics of the static, rotating, and charged-rotating BTZ black holes will be verified.
On non-linear magnetic-charged black hole surrounded by quintessence
NASA Astrophysics Data System (ADS)
Nam, Cao H.
2018-06-01
We derive a non-linear magnetic-charged black hole surrounded by quintessence, which behaves asymptotically like the Schwarzschild black hole surrounded by quintessence but at the short distances like the dS geometry. The horizon properties of this black hole are investigated in detail. The thermodynamics of the black hole is studied in the local and global views. Finally, by calculating the heat capacity and the free energy, we point to that the black hole may undergo a thermal phase transition, between a larger unstable black hole and a smaller stable black hole, at a critical temperature.
Performance evaluation of two black nickel and two black chrome solar collectors
NASA Technical Reports Server (NTRS)
Losey, R.
1977-01-01
The test program was based on the evaluation of four unique solar collectors described below: (1) black nickel collector surface with a desiccant drying bed, (2) black nickel collector surface without a desiccant drying bed, (3) black chrome collector surface with a dessicant drying bed, and (4) black chrome collector surface without a desiccant drying bed. The test program included three distinct phases: Initial performance evaluation, natural environmental aging, and post-aging performance evaluation. Results of Phase III testing conclusively indicated a higher normalized efficiency for Black Chrome surfaces when compared to Black Nickel.
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
Rhetorical Perspectivism of Black Congressmen upon the 1875 Civil Rights Bill.
ERIC Educational Resources Information Center
Haskins, William A.
In their new roles as congressmen after the Civil War, blacks, for the first time in American history, advanced views of civil rights that reflected black perspectives. One scheme for analyzing black rhetoric suggests that black congressmen did not share the perspective held by many whites--that blacks were inept individuals. Rather, the black…
Relation of Racial Identity Attitudes to Self-Actualization and Affective States of Black Students.
ERIC Educational Resources Information Center
Parham, Thomas A.; Helms, Janet E.
1985-01-01
The relation between identity attitudes, or Black self-ac4ualization, and various affective states were investigated in 166 Black university students. Both pro-White/anti-Black and pro-Black/anti-White attitudes were associated with greater personal distress. Awakening Black identity was positively related to self-actualization tendencies and…
Sex Stereotyping in a Selected Sample of Black American Adolescents.
ERIC Educational Resources Information Center
Wilson, Maurice T.; Koeske, Gary F.
The present study investigated three major hypotheses: (1) that black respondents' judgments of black targets would show greater uniformity than their judgments of white targets; (2) that, contrary to trends in white samples, black males would be perceived less positively than black females; and (3) that self-ratings for black males would be less…
The Black Teacher Project: How Racial Affinity Professional Development Sustains Black Teachers
ERIC Educational Resources Information Center
Mosely, Micia
2018-01-01
The Black Teacher Project (BTP) is an organization that supports, develops and sustains Black teachers for schools in the United States. The organization is building a Black teaching force that reflects the diversity and excellence of Black people in the United States. In our pilot year, BTP offered racial affinity-based professional development…
ERIC Educational Resources Information Center
McLemore, Leslie Burl
1975-01-01
Considers the potential impact of black revolutionary nationalism--cultural and military--upon the social patterns of black people, arguing that a racial, cultural, and military approach through black organizations with a highly developed system of communications holds the key to black salvation in America. (Author/JM)
Black Women in the Academy: The Secrets to Success and Achievement.
ERIC Educational Resources Information Center
Gregory, Sheila T.
This book presents selected historical data focusing on three aspects in the lives of Black women: resilience of Black women and their families; strengths of the Black church and community; and formidable gains made by Black women in the workforce. The status and achievements of Black women professors and scholars in the academy are reviewed, with…
ERIC Educational Resources Information Center
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,…
Black Hole Safari: Tracking Populations and Hunting Big Game
NASA Astrophysics Data System (ADS)
McConnell, N. J.
2013-10-01
Understanding the physical connection, or lack thereof, between the growth of galaxies and supermassive black holes is a key challenge in extragalactic astronomy. Dynamical studies of nearby galaxies are building a census of black hole masses across a broad range of galaxy types and uncovering statistical correlations between galaxy bulge properties and black hole masses. These local correlations provide a baseline for studying galaxies and black holes at higher redshifts. Recent measurements have probed the extremes of the supermassive black hole population and introduced surprises that challenge simple models of black hole and galaxy co-evolution. Future advances in the quality and quantity of dynamical black hole mass measurements will shed light upon the growth of massive galaxies and black holes in different cosmic environments.
Thermodynamics of a class of regular black holes with a generalized uncertainty principle
NASA Astrophysics Data System (ADS)
Maluf, R. V.; Neves, Juliano C. S.
2018-05-01
In this article, we present a study on thermodynamics of a class of regular black holes. Such a class includes Bardeen and Hayward regular black holes. We obtained thermodynamic quantities like the Hawking temperature, entropy, and heat capacity for the entire class. As part of an effort to indicate some physical observable to distinguish regular black holes from singular black holes, we suggest that regular black holes are colder than singular black holes. Besides, contrary to the Schwarzschild black hole, that class of regular black holes may be thermodynamically stable. From a generalized uncertainty principle, we also obtained the quantum-corrected thermodynamics for the studied class. Such quantum corrections provide a logarithmic term for the quantum-corrected entropy.
"Iron-Clad" Evidence For Spinning Black Hole
NASA Astrophysics Data System (ADS)
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 competing explanations that do not require extreme gravitational effects, and provide the best look yet at the geometry of the space-time around a stellar black hole created by the death of a massive star." The orbit of a particle near a black hole depends on the curvature of space around the black hole, which also depends on how fast the black hole is spinning. A spinning black hole drags space around with it and allows atoms to orbit closer to the black hole than is possible for a non-spinning black hole. The latest Chandra data from Cygnus X-1, the first stellar-size black hole discovered, show that the gravitational effects on the signal from the iron atoms can only be due to relativistic effects, and that some of the atoms are no closer than 100 miles to the black hole. There was no evidence that the Cygnus X-1 black hole is spinning. The XMM-Newton data from the black hole, XTE J1650-500, show a very similar distribution of iron atom X-rays with one important exception. More low energy X-rays from iron atoms are observed, an indication that some X-rays are coming from deep in the gravitational well around the black hole, as close as 20 miles to the black hole event horizon. This black hole must be spinning rapidly. Chandra observations of a third stellar black hole, GX 339-4, have revealed that it is also spinning rapidly, and clouds of warm absorbing gas appear to be flowing away from the black hole at speeds of about three hundred thousand miles per hour. Such warm gas flows have been observed in the vicinity of supermassive black holes. Previous observations of some supermassive black holes by Japan's ASCA satellite, XMM-Newton and Chandra have indicated that they may also be rotating rapidly. The latest results presented by Miller indicate that the peculiar geometry of space around spinning stellar-mass black holes and supermassive black holes is remarkably similar. Stellar and supermassive black holes may be similar in other ways. Powerful jets of high-energy particles have been detected around both types of black holes. Why do some stellar black holes spin rapidly and others not? One possibility is that differences in spin are imparted at birth when a massive star collapses. Another possibility is that the spin rate depends on how long the black hole has been devouring matter from its companion star, a process that makes the black hole spin faster. Black holes with more rapid spin, XTE J1650-500 and GX 339-4, have low-mass companion stars. These relatively long-lived stars may have been feeding the black hole for longer, allowing it to spin up to faster rates. Cygnus X-1 with its short-lived companion star may not have not time to spin up. Miller is a National Science Foundation Astronomy & Astrophysics Postdoctoral Fellow. His primary collaborators in this work were Walter Lewin if the Massachusetts Institute of Technology in Cambridge, Andrew Fabian of the University of Cambridge, UK, and Chris Reynolds of the University of Maryland, College Park. NASA's Marshall Space Flight Center, Huntsville, Ala., manages the Chandra program for the Office of Space Science, NASA Headquarters, Washington. Northrop Grumman of Redondo Beach, Calif., formerly TRW, Inc., was the prime development contractor for the observatory. The Smithsonian Astrophysical Observatory controls science and flight operations from the Chandra X-ray Center in Cambridge, Mass.
Gamma ray bursts of black hole universe
NASA Astrophysics Data System (ADS)
Zhang, T. X.
2015-07-01
Slightly modifying the standard big bang theory, Zhang recently developed a new cosmological model called black hole universe, which has only a single postulate but is consistent with Mach's principle, governed by Einstein's general theory of relativity, and able to explain existing observations of the universe. In the previous studies, we have explained the origin, structure, evolution, expansion, cosmic microwave background radiation, quasar, and acceleration of 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 study investigates gamma ray bursts of black hole universe and provides an alternative explanation for the energy and spectrum measurements of gamma ray bursts according to the black hole universe model. The results indicate that gamma ray bursts can be understood as emissions of dynamic star-like black holes. A black hole, when it accretes its star or merges with another black hole, becomes dynamic. A dynamic black hole has a broken event horizon and thus cannot hold the inside hot (or high-frequency) blackbody radiation, which flows or leaks out and produces a GRB. A star when it collapses into its core black hole produces a long GRB and releases the gravitational potential energy of the star as gamma rays. A black hole that merges with another black hole produces a short GRB and releases a part of their blackbody radiation as gamma rays. The amount of energy obtained from the emissions of dynamic star-like black holes are consistent with the measurements of energy from GRBs. The GRB energy spectra derived from this new emission mechanism are also consistent with the measurements.
The Black dentist workforce in the United States.
Mertz, Elizabeth; Calvo, Jean; Wides, Cynthia; Gates, Paul
2017-03-01
The purpose of this paper is to describe the Black dentist workforce, the practice patterns of providers, and their contributions to oral health care for minority and underserved patients. A national sample survey of underrepresented minority dentists was conducted in 2012 and received a 32.6 percent response rate for self-reported Black dentists. Data were weighted for selection and response bias to be nationally representative. Descriptive and multivariable statistics were computed to provide a workforce profile of Black dentists. National comparisons are provided from published data. Among all Black dentists (weighted n = 6,254), 76.6 percent self-identify as African-American, 13.2 percent as African, and 10.3 percent as Afro-Caribbean. The largest share of Black dentists are male, married, heterosexual, born in the United States and raised in a medium to large city. One third of Black dentists were the first in their family to graduate from college. Black dentists report higher average educational debt than all dental students, with graduates from International Dentist Programs having the greatest debt. Traditional practices (i.e., private practices) dominate, with 67.1 percent of Black dentists starting out in this setting and 73.5 percent currently in the setting. Black dentists care for a disproportionate share of Black patients, with an average patient mix that is 44.9 percent Black. Two in five Black dentists reported their patient pool is made up of more than 50 percent Black patients. The underrepresentation for Black dentists is extraordinary, and the Black dentists that are in practice are shouldering a disproportionate share of dental care for minority and underserved communities. © 2016 American Association of Public Health Dentistry.
NASA Astrophysics Data System (ADS)
Chang, Sae Jung; Jeong, Gi Young; Kim, Soo Jin
Since the Gosu, Ondal, and Sungryu karst caves in South Korea became open to the public several decades ago, the surface of their speleothems has been turning black due to pollutants. The black pollutant is concentrated at the surface of speleothems, and the surface black layer is 0.1 to several millimeters thick. Elemental measurements of three bulk, acid-dissolved and oxidized fractions of the surface black layer show that the black pigment is a black carbon. The black carbon correlates positively with sulfates, nitrates, manganese, and lead, which are typical tracers of industrial and urban emissions. The 14C-measurement of the black carbon, using accelerator mass spectrometry, shows that the black carbon was derived from both fossil-fuel combustion and biomass burning in roughly equal amounts, evidenced by fC value ranging from 0.340 to 0.592 (<±0.004, 1 σ). Therefore, protection of speleothems from black coloration requires control of anthropogenic black carbons carried by visitors. Suitable measures might include closure of caves, air cleaning of visitors and regulation of visitor numbers. The application of radiocarbon measurement of black carbon suggests that the fC is a valuable proxy for tracing the blackening phenomenon of natural and cultural heritage sites such as caves.
REPORT TO CONGRESS ON BLACK CARBON
The Report to Congress on Black Carbon describes domestic and international sources of black carbon emissions, and summarizes available scientific information on the climate effects of black carbon. Further, the Report evaluates available black carbon mitigation options and thei...
Celebration of Black Composers: Black Music at the Philharmonic
ERIC Educational Resources Information Center
Current, Gloster B.
1978-01-01
The five-day celebration of black composers at the New York Philharmonic included a panel discussion of black music and three symphonic concerts featuring the premieres of new works by celebrated black composers. (Author/AM)
Pyrolytic carbon coated black silicon
NASA Astrophysics Data System (ADS)
Shah, Ali; Stenberg, Petri; Karvonen, Lasse; Ali, Rizwan; Honkanen, Seppo; Lipsanen, Harri; Peyghambarian, N.; Kuittinen, Markku; Svirko, Yuri; Kaplas, Tommi
2016-05-01
Carbon is the most well-known black material in the history of man. Throughout the centuries, carbon has been used as a black material for paintings, camouflage, and optics. Although, the techniques to make other black surfaces have evolved and become more sophisticated with time, carbon still remains one of the best black materials. Another well-known black surface is black silicon, reflecting less than 0.5% of incident light in visible spectral range but becomes a highly reflecting surface in wavelengths above 1000 nm. On the other hand, carbon absorbs at those and longer wavelengths. Thus, it is possible to combine black silicon with carbon to create an artificial material with very low reflectivity over a wide spectral range. Here we report our results on coating conformally black silicon substrate with amorphous pyrolytic carbon. We present a superior black surface with reflectance of light less than 0.5% in the spectral range of 350 nm to 2000 nm.
Black and brown pigment gallstones differ in microstructure and microcomposition.
Malet, P F; Takabayashi, A; Trotman, B W; Soloway, R D; Weston, N E
1984-01-01
The two subtypes of pigment gallstones, black and brown stones, differ in chemical composition and pathogenesis. We examined a black bilirubinate stone and a black phosphate stone (which represented opposite ends of the compositional spectrum of black noncarbonate stones), a black carbonate stone, and a brown pigment stone using scanning electron microscopy and microchemical techniques to determine if stone microstructure and microcomposition reflected different patterns of formation. The cross-sectional surfaces of the black bilirubinate and black phosphate stones were smooth and homogenous. Electron probe microanalysis demonstrated high concentrations of sulfur and copper in the center of the black bilirubinate stone; sulfur was in a low valence state consistent with disulfide linkages in proteins. The brown stone was rough-surfaced with lamellated bands on cross-section. The lighter-colored bands in this stone contained virtually all of the detected calcium palmitate, while the darker sections contained much more calcium bilirubinate. Plasma oxygen etching demonstrated a network of protein interdigitating with calcium bilirubinate salts in the black bilirubinate and black phosphate stones but not in the black carbonate or brown stones. Argon ion etching demonstrated that calcium bilirubinate was in a closely packed rod-shaped arrangement in all three black stones but not in the brown stone. We conclude that the marked differences in structure and composition between the black noncarbonate and brown pigment gallstones support the hypothesis that the two major pigment gallstone types form by different mechanisms. In addition, the layered structures of the black carbonate and brown stones suggest that stone growth is affected by cyclic changes in biliary composition.
A black berry that is not a blackberry
USDA-ARS?s Scientific Manuscript database
Red raspberries and blackberries, unlike black raspberries, are widespread and familiar. Most consumers rarely encounter black raspberries; consequently, they frequently confuse fresh black raspberries with common cane berries. Recognition and appreciation of black raspberries can be improved with c...
Black Literature vs. Black Studies: Three Lynchings
ERIC Educational Resources Information Center
Williams, Melvin G.
1977-01-01
Considers three works by black authors, all dealing with lynchings, that may be used in a black literature course to introduce students to the esthetic dimension of black literature, as well as to its cultural and racial significance. (GW)
ERIC Educational Resources Information Center
Bethell, Detra
2013-01-01
The dominant discourse regarding Black males in America is that they are less academically successful than European American males and Black females. Similarly, Black males in the Bahamas are described as less successful than Black Bahamian females. School Counselors are in a unique position to alter the trajectory of success for Black males if…
Locating Black Mixed-Raced Males in the Black Supplementary School Movement
ERIC Educational Resources Information Center
Joseph-Salisbury, Remi; Andrews, Kehinde
2017-01-01
This article draws upon data from semi-structured interviews conducted with black mixed-race males in the UK and the US, to argue that a revival of the black supplementary school movement could play an important role in the education of black mixed-race males. The article contends that a strong identification with blackness, and a concomitant…
"No Cosby Show": Single Black Mother Homes and How Black Men Build Romantic Relationships
ERIC Educational Resources Information Center
Moore, Maia Niguel
2016-01-01
This qualitative study explored the lives of 11 Black men to better understand how Black men who were raised in single Black mother homes build romantic relationships with Black women. One focus group and a series of individual in-person interviews were conducted with the participants who ranged between 23 and 43 years of age. Participants were…
Is Nursing a Viable Career for Blacks? (A Study of Black and White Freshman Nursing Students).
ERIC Educational Resources Information Center
Miller, Michael H.
It has been suggested that underrepresentation of blacks in professional nursing results from insufficient black-nurse role models. This study of 331 black and white freshman nursing students in three, two year, associate degree programs argues that blacks are not professional nurses for reasons other than a lack of role models. The results show…
Rotating black holes in dilatonic Einstein-Gauss-Bonnet theory.
Kleihaus, Burkhard; Kunz, Jutta; Radu, Eugen
2011-04-15
We construct generalizations of the Kerr black holes by including higher-curvature corrections in the form of the Gauss-Bonnet density coupled to the dilaton. We show that the domain of existence of these Einstein-Gauss-Bonnet-dilaton (EGBD) black holes is bounded by the Kerr black holes, the critical EGBD black holes, and the singular extremal EGBD solutions. The angular momentum of the EGBD black holes can exceed the Kerr bound. The EGBD black holes satisfy a generalized Smarr relation. We also compare their innermost stable circular orbits with those of the Kerr black holes and show the existence of differences which might be observable in astrophysical systems.
Han, Xiao; Wang, Hai Bo; Wang, Xiao di; Shi, Xiang Bin; Wang, Bao Liang; Zheng, Xiao Cui; Wang, Zhi Qiang; Liu, Feng Zhi
2017-10-01
The photo response curves of 11 rootstock-scion combinations including summer black/Beta, summer black/1103P, summer black/101-14, summer black/3309C, summer black/140Ru, summer black/5C, summer black/5BB, summer black/420A, summer black/SO4, summer black/Kangzhen No.1, summer black/Huapu No.1 were fitted by rectangular hyperbola mo-del, non-rectangular hyperbola model, modified rectangular hyperbola model and exponential model respectively, and the differences of imitative effects were analyzed by determination coefficiency, light compensation point, light saturation point, initial quantum efficiency, maximum photosynthetic rate and dark respiration rate. The result showed that the fit coefficients of all four models were above 0.98, and there was no obvious difference on the fitted values of light compensation point among the four models. The modified rectangular hyperbola model fitted best on light saturation point, apparent quantum yield, maximum photosynthetic rate and dark respiration rate, and had the minimum AIC value based on the akaike information criterion, therefore, the modified rectangular hyperbola model was the best one. The clustering analysis indicated that summer black/SO4 and summer black/420A combinations had low light compensation point, high apparent quantum yield and low dark respiration rate among 11 rootstock-scion combinations, suggesting that these two combinations could use weak light more efficiently due to their less respiratory consumption and higher weak light tolerance. The Topsis comparison method ranked summer black/SO4 and summer black/420A combinations as No. 1 and No. 2 respectively in weak light tolerance ability, which was consistent with cluster analysis. Consequently, summer black has the highest weak light tolerance in case grafted on 420A or SO4, which could be the most suitable rootstock-scion combinations for protected cultivation.
Revisit on the thermodynamic stability of Hořava-Lifshitz black hole
NASA Astrophysics Data System (ADS)
Meng, Xudong; Wang, Ruihong
We study the thermodynamic properties of the black hole derived in Hořava-Lifshitz (HL) gravity without the detailed-balance condition. The parameter Ξ = 𝜖2 in the HL black hole plays the same role as that of the electric charge in the Reissner-Nordström-anti-de Sitter (RN-AdS) black hole. By analogy, we treat the parameter Ξ as the thermodynamic variable and obtain the first law of thermodynamics for the HL black hole. Although the HL black hole and the RN-AdS black hole have the similar mass and temperature, due to their very different entropy, the two black holes have very different thermodynamic properties. By calculating the heat capacity and the free energy, we analyze the thermodynamic stability of the HL black hole.
Supersymmetric black holes and Freudenthal duality
NASA Astrophysics Data System (ADS)
Marrani, Alessio; Mandal, Taniya; Tripathy, Prasanta K.
2017-07-01
We study the effect of Freudenthal duality on supersymmetric extremal black hole attractors in 𝒩 = 2, D = 4 ungauged supergravity. Freudenthal duality acts on the dyonic black hole charges as an anti-involution which keeps the black hole entropy and the critical points of the effective black hole potential invariant. We analyze its effect on the recently discovered distinct, mutually exclusive phases of axionic supersymmetric black holes, related to the existence of nontrivial involutory constant matrices. In particular, we consider a supersymmetric D0 - D4 - D6 black hole and we explicitly Freudenthal-map it to a supersymmetric D0 - D2 - D4 - D6 black hole. We thus show that the charge representation space of a supersymmetric D0 - D2 - D4 - D6 black hole also contains mutually exclusive domains.
Thermodynamic and classical instability of AdS black holes in fourth-order gravity
NASA Astrophysics Data System (ADS)
Myung, Yun Soo; Moon, Taeyoon
2014-04-01
We study thermodynamic and classical instability of AdS black holes in fourth-order gravity. These include the BTZ black hole in new massive gravity, Schwarzschild-AdS black hole, and higher-dimensional AdS black holes in fourth-order gravity. All thermo-dynamic quantities which are computed using the Abbot-Deser-Tekin method are used to study thermodynamic instability of AdS black holes. On the other hand, we investigate the s-mode Gregory-Laflamme instability of the massive graviton propagating around the AdS black holes. We establish the connection between the thermodynamic instability and the GL instability of AdS black holes in fourth-order gravity. This shows that the Gubser-Mitra conjecture holds for AdS black holes found from fourth-order gravity.
Perturbations of the Kerr black hole and the boundness of linear waves
NASA Astrophysics Data System (ADS)
Eskin, G.
2010-11-01
Artificial black holes (also called acoustic or optical black holes) are the black holes for the linear wave equation describing the wave propagation in a moving medium. They attracted a considerable interest of physicists who study them to better understand the black holes in general relativity. We consider the case of stationary axisymmetric metrics and we show that the Kerr black hole is not stable under perturbations in the class of all axisymmetric metrics. We describe families of axisymmetric metrics having black holes that are the perturbations of the Kerr black hole. We also show that the ergosphere can be determined by boundary measurements. Finally, we prove the uniform boundness of the solution in the exterior of the black hole when the event horizon coincides with the ergosphere.
Black Pete through the Eyes of Dutch Children
Mesman, Judi; Janssen, Sofie; van Rosmalen, Lenny
2016-01-01
The traditional figure of Black Pete seen during the December festivities around Sinterklaas (the Dutch Santa Claus) in the Netherlands has sparked fierce debates about his racial stereotypical characteristics and his potentially negative effects on children’s opinions about black people. The Black Pete phenomenon has even been discussed by the United Nations Committee on the Elimination of Racial Discrimination, resulting in a report urging the Netherlands to eliminate this form of racial stereotyping. The adult debate about Black Pete is clearly important, but Sinterklaas is essentially a children’s holiday. Surprisingly, there have never been any systematic studies to examine children’s views on Black Pete. The current study is the first to do so. In a sample of 201 children aged 5–7 years, we collected free descriptions of Black Pete, asked children to group him in relation to other figures, and to assign characteristics to him and comparison figures. The results showed that (1) Children are clearly aware of Black Pete’s skin color and subordinate status; (2) Children associate Black Pete more with clowns than with black people; (3) Children evaluate Black Pete very positively, but the positive characteristics do not generalize to their evaluation of black people. The findings illustrate the deep-rooted childhood origins of many Dutch people’s affection for Black Pete and their lack of awareness of his relation to racial stereotypes. This explains the resistance to changing the Black Pete figure and the slowness of the change process on this front. PMID:27322583
Black Hessians: American Blacks as German Soldiers.
ERIC Educational Resources Information Center
Hoffman, Elliott W.
1981-01-01
The German army in America during the Revolutionary War enlisted Blacks as musicians, laborers, and soldiers. Black soldiers contributed to the mercenaries' military activities, while the German units offered Blacks employment, clothing, food, and a type of escape from slavery. (Author/MJL)
ERIC Educational Resources Information Center
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)
Differences Between Black Youth who Support the Black Panthers and the NAACP.
ERIC Educational Resources Information Center
Levine, Daniel U.; And Others
The purpose of this study is to compare the attitudes of black youth who have a favorable orientation toward the Black Panthers with those of black youth who appear to be oriented toward the N.A.A.C.P. Information involving orientations toward organizations concerned with the lives of black Americans was collected as part of a larger study on the…
Black Theatre: Ideas That Matter in the Pursuit of Human Dignity.
ERIC Educational Resources Information Center
Sandle, Floyd L.
Black theatre has come a long way from the major stereotypes of black people established by white playwrights, but it is still trying to convey the fact that blacks remain in a kind of prison. The slow pace of black theatre in becoming art is obviously due to the long degradation of blacks, the tolerated injustice of whites, and the belated…
A Prime Assessment for Black Colleges: Role of Blacks in the Sciences and Related Fields.
ERIC Educational Resources Information Center
Branson, Herman
1978-01-01
This article examines the need for blacks in science and engineering. From a review of the history of blacks as objects of scientific study from the 1790s to the present a better grasp of the problems confronting blacks can be gained by examining two fields: genetics and psychology. In genetic research on blacks, the results are used not by…
Jefferies, Keisha; Goldberg, Lisa; Aston, Megan; Murphy, Gail Tomblin
2018-05-12
This paper explores the invisibility and underrepresentation of Black nurses in formal and informal leadership roles using a Black feminist poststructuralist framework. The paper describes historical and contemporary challenges experienced by Black nurses throughout their nursing education and in practice. It also highlights how social and institutional discourses continue to marginalize and oppress Black nurses as leaders and render them invisible. Diversity amongst nursing leaders is essential to inform health care delivery, develop inclusive practices and provide culturally sensitive care. Despite this glaring need for diversity within nursing in Canada, there remains a significant underrepresentation of Black nurses in the workforce and as leaders. This is a discursive paper on Black nurses in nursing education and the workforce as well as their location as leaders in health care through a critical analysis using Black feminist poststructuralism. A review of the literature involved searching electronic databases CINAHL, NovaNet, PubMed and Google Scholar using keywords including: Black; African; Nurses; Leaders; Feminism; Poststructural. Articles were screened by titles and abstracts before accessing full-text for relevant articles. Black feminist poststructuralism uncovers how power, language, subjectivity and agency are constructed by the historically ingrained social and institutional discourses of everyday life for Black nurses. Experiences of discrimination and oppression were common throughout nursing education and practice for Black nurses, resulting in feelings of marginalization and isolation. The invisibility of Black nurse leaders is the result of generational oppression and discrimination manifested through discourses. Systemic, institutional and historical discourses perpetuate barriers for Black nurse leaders, resulting in their invisibility or absence in practice. This paper is designed to generate discussion related to the invisibility of Black nurse leaders by providing an understanding of the historical experiences of Blacks, their entry into the nursing profession and the present day challenges they face. This discussion will inform health care practice, policy, and structuring by identifying the barriers to leadership for Black nurses. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
A Sprinkle of Pepper: The State of Black Influence in White Colleges and Universities
ERIC Educational Resources Information Center
Hale, Frank W., Jr.
1975-01-01
The influence of Blacks in white institutions of higher education is no more than a sprinkling of pepper. The article discusses some problems facing the Black students, Black faculty and Black administrators at these schools. (Author/HMV)
40 CFR 458.40 - Applicability; description of the carbon black lamp process subcategory.
Code of Federal Regulations, 2011 CFR
2011-07-01
... carbon black lamp process subcategory. 458.40 Section 458.40 Protection of Environment ENVIRONMENTAL... CATEGORY Carbon Black Lamp Process Subcategory § 458.40 Applicability; description of the carbon black lamp... production of carbon black by the lamp process. ...
Land of Promise, Cities of Despair: Blacks in Urban America.
ERIC Educational Resources Information Center
Staples, Robert
1978-01-01
This article discusses the current effect on Blacks of unequal political and economic power in American cities. Some of the issues examined include: Black migration; employment status; education; socioeconomic status; Black suicide; Black political power; housing; health; and racism. (EB)
Fermions tunnelling from the charged dilatonic black holes
NASA Astrophysics Data System (ADS)
Chen, De-You; Jiang, Qing-Quan; Zu, Xiao-Tao
2008-10-01
Kerner and Mann's recent work shows that for an uncharged and non-rotating black hole its Hawking temperature can be correctly derived by fermions tunnelling from its horizons. In this paper, our main work is to improve the analysis to deal with charged fermion tunnelling from the general dilatonic black holes, specifically including the charged, spherically symmetric dilatonic black hole, the rotating Einstein Maxwell dilaton axion (EMDA) black hole and the rotating Kaluza Klein (KK) black hole. As a result, the correct Hawking temperatures are well recovered by charged fermions tunnelling from these black holes.
Throat quantization of the Schwarzschild-Tangherlini(-AdS) black hole
NASA Astrophysics Data System (ADS)
Maeda, Hideki
2018-01-01
By the throat quantization pioneered by Louko and Mäkelä, we derive the mass and area/entropy spectra for the Schwarzschild-Tangherlini-type asymptotically flat or AdS vacuum black hole in arbitrary dimensions. Using the WKB approximation for black holes with large mass, we show that area/entropy is equally spaced for asymptotically flat black holes, while mass is equally spaced for asymptotically AdS black holes. Exact spectra can be obtained for toroidal AdS black holes in arbitrary dimensions including the three-dimensional BTZ black hole.
Black holes of dimensionally continued gravity coupled to Born-Infeld electromagnetic field
NASA Astrophysics Data System (ADS)
Meng, Kun; Yang, Da-Bao
2018-05-01
In this paper, for dimensionally continued gravity coupled to Born-Infeld electromagnetic field, we construct topological black holes in diverse dimensions and construct dyonic black holes in general even dimensions. We study thermodynamics of the black holes and obtain first laws. We study thermal phase transitions of the black holes in T-S plane and find van der Waals-like phase transitions for even-dimensional spherical black holes, such phase transitions are not found for other types of black holes constructed in this paper.
Substantial Family History of Prostate Cancer in Black Men Recruited for Prostate Cancer Screening
Mastalski, Kathleen; Coups, Elliot J.; Ruth, Karen; Raysor, Susan; Giri, Veda N.
2008-01-01
Background Black men are at increased risk for prostate cancer (PCA), particularly with a family history (FH) of the disease. Previous reports have raised concern for suboptimal screening of Black men with a FH of PCA. We report on the extent of FH of PCA from a prospective, longitudinal PCA screening program for high-risk men. Methods Black men ages 35-69 are eligible for PCA screening through the Prostate Cancer Risk Assessment Program (PRAP) regardless of FH. Rates of self-reported FH of PCA, breast, and colon cancer at baseline were compared with an age-matched sample of Black men from the 2005 National Health Interview Survey (NHIS) using standard statistical methods. Results As of January 2007, 332 Black men with pedigree information were enrolled in PRAP and FH of PCA was compared to 838 Black men from the 2005 NHIS. Black men in PRAP reported significantly more first-degree relatives with PCA compared to Black men in the 2005 NHIS (34.3%, 95% CI 29.2-39.7 vs. 5.7%, 95% CI 3.9-7.4). Black men in PRAP also had more FH of breast cancer compared to the 2005 NHIS (11.5%, 95% CI 8.2-15.4 vs 6.3%, 95% CI 4.6-8.0). Conclusions FH of PCA appears to be a motivating factor for Black men seeking PCA screening. Targeted recruitment and education among Black families should improve PCA screening rates. Efforts to recruit Black men without a FH of PCA are also needed. Condensed Abstract Black men seeking prostate cancer screening have a substantial burden of family history of prostate cancer. Targeted education and enhancing discussion in Black families should increase prostate cancer screening and adherence. PMID:18816608
A Comparison of Birth Outcomes Among Black, Hispanic, and Black Hispanic Women
BeLue, Rhonda; Hillemeier, Marianne M.
2015-01-01
Background While non-Hispanic Black populations tend to be disproportionately affected by adverse reproductive outcomes, Hispanic populations tend to demonstrate healthier birth outcomes, regardless of socioeconomic background. Little is known about birth outcomes for women who are both Black and Hispanic. We examined whether birth outcomes and risk factors for women who are both Black and Hispanic most closely resemble those of women who are only Black or Hispanic and also compared these outcomes to those for Whites. Methods Using the 2013 US natality files, we examined 2,970,315 singleton births to Black Hispanic, Hispanic, Black, and White mothers. We used logistic regression to calculate predicted probabilities of low birth weight (LBW), preterm birth (PTB), or small for gestational age (SGA). Race-stratified regression analysis was used to identify the factors that significantly predicted risk for each outcome for each racial/ethnic group. Results Black mothers had the highest prevalence and predicted probabilities of experiencing all three outcomes. Black Hispanic mothers were less likely than Black mothers and more likely than Hispanic mothers to experience each of the adverse outcomes. We also found support for racial variation in risk and protective factors for mothers in the different groups. Factors like age and education inconsistently predicted risk of experiencing the birth outcomes for all groups. Overall, Black Hispanic mothers had birth outcomes and risk factor profiles like Hispanic mothers, although they had sociodemographic characteristics and health behaviors like Black mothers. Conclusions Patterning of birth outcomes among Black Hispanic women suggest an intersection of risk and protective factors associated with their respective racial and ethnic identities. Additional information about sociodemographic context is needed to develop a more complete picture of how factors related to race and ethnic group membership influence Black Hispanic women’s birth outcomes. PMID:26561541
The specter of the black fag: parody, blackness, and hetero/homosexual B(r)others.
Johnson, E Patrick
2003-01-01
This essay investigates the ways in which three African American heterosexual males-Eddie Murphy, Damon Wayans, and David Alan Grier-appropriate signifiers of gayness to parody, stereotype, and repudiate black gay men. These performances are also attempts to circumscribe the boundaries of blackness, ultimately suggesting that "authentic" blackness is lodged within hegemonic black masculinity. Contrary to this desired effect, the essay demonstrates how these performers, in the act of repudiation, ironically and unwittingly queer heteronormative black masculinity, securing further the dialectic between heterosexuality and homosexuality. Finally, the essay argues that these performances manifest the black heterosexual male's melancholia, his refusal to grieve the loss of his sexual B(r)other.
Robinson, Michael A; Jones-Eversley, Sharon; Moore, Sharon E; Ravenell, Joseph; Adedoyin, A Christson
2018-06-01
This article explores the role the Black Church could play in facilitating spiritually sensitive, culturally relevant and gender-specific services to address the mental health and well-being of Black males. The help-seeking behaviors of Black men are examined as the authors offer two theories: the body, mind, spirit, environment, social, transcendent, and health, illness, men, and masculinities that may assist the Black Church in functioning as an effective support networks for healthy Black male mental health. Next, the authors discuss implications for practice, research, and education, and lastly, eight recommendations for Black Church leadership, social workers, and mental health professionals are also discussed.
World-volume effective theory for higher-dimensional black holes.
Emparan, Roberto; Harmark, Troels; Niarchos, Vasilis; Obers, Niels A
2009-05-15
We argue that the main feature behind novel properties of higher-dimensional black holes, compared to four-dimensional ones, is that their horizons can have two characteristic lengths of very different size. We develop a long-distance world-volume effective theory that captures the black hole dynamics at scales much larger than the short scale. In this limit the black hole is regarded as a blackfold: a black brane (possibly boosted locally) whose world volume spans a curved submanifold of the spacetime. This approach reveals black objects with novel horizon geometries and topologies more complex than the black ring, but more generally it provides a new organizing framework for the dynamics of higher-dimensional black holes.
Population ecology and harvest of the American black duck: a review
Rusch, D.H.; Ankney, C.D.; Boyd, H.; Longcore, J.R.; Montalbano, F.; Ringelman, J.K.; Stotts, V.D.
1989-01-01
1. The purpose of our review was to examine available data on population trends and current status of black ducks and trends in natality and survival and to relate these, where possible, to changes in habitat, predation, disease, contaminants, harvest, and hybridization with mallards. 2. The number of black ducks tallied in the winter survey has declined steadily over the past 30 years at an average rate of about 3%/ year. Reliability and precision of the survey are uncertain; it may not provide an adequate index to the continental population of black ducks. Breeding surveys are incomplete and sporadic, but black ducks have decreased in Ontario and increased in the Maritime Provinces and Quebec. 3. Recent declines in numbers of black ducks tallied in the winter survey are not unusual in magnitude or much different from those that have occurred among several other species of waterfowl. 4. At present, black ducks are not especially scarce relative to numbers of several other ducks in eastern North America. 5. There is no solid evidence of major decreases in quality or quantity of breeding habitat for black ducks in recent years; in some areas, habitat has improved. 6. Natural mortality of black ducks has not been well studied, but does not seem unusually high compared to other dabbling ducks. 7. Harvest rates of black ducks are similar to those of sympatric mallards as determined by banding analyses. 8. There is no strong evidence for direct effects of contaminants on black ducks, but some indirect effects through invertebrate food resources have been detected. 9. Age ratios in black ducks show no trend in the past 18 years. 10. The quality and quantity of wintering habitat for black ducks have decreased substantially in some areas. 11. Disease and other natural mortality that affect black ducks do .not occur in unusually high frequency. 12. A decline in harvest of black ducks has occurred; most of the decline has been in the United States, especially since restrictive regulations were implemented in 1983. 13. Recovery rates of black ducks have declined recently in the U.S., but not in Canada. 14. Survival rates of black ducks are 56-63% for adults and 43% for young. These rates of survival are similar to comparable estimates in sympatric mallards. 15. Long hunting seasons may depress survival in some sex-age classes of black ducks, buteffects of small reductions in survival on population trends are unknown. 16. Available evidence does not support the contention that hunting is either the sole or most important cause of the decline in the winter tally of black duck numbers. 17. Surveys and banding of black ducks should be thoroughly reviewed and maintained or improved as warranted. Obtaining or maintaining a reasonable index to numbers of black ducks is the top priority among survey needs. 18. Experimental manipulation of hunting seasons should be considered to elucidate relationships among regulations, harvest, survival, and population trends. 19. Black ducks and mallards are genetically similar; there is as much genetic differentiation within the 2 species as there is between them. 20. Black duck x mallard hybrids are fertile. Hybrids are difficult to detect by plumage and thus published frequencies (0-13%) of hybrids may be low. 21. Hybridization could be a result of concomitant mallard increases and black duck decreases, or changes in black duck-to-mallard ratios could be from hybridization and genetic swamping of black ducks.
BlackMax: A black-hole event generator with rotation, recoil, split branes, and brane tension
NASA Astrophysics Data System (ADS)
Dai, De-Chang; Starkman, Glenn; Stojkovic, Dejan; Issever, Cigdem; Rizvi, Eram; Tseng, Jeff
2008-04-01
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.
1999-11-30
This three-dimensional illustration shows how the rotating space around a black hole twists up the magnetic field in the plasma falling toward the black hole. The black sphere at the center of the figure is the black hole itself. http://photojournal.jpl.nasa.gov/catalog/PIA04207
Mouzon, Dawne M; Watkins, Daphne C; Perry, Ramona; Simpson, Theresa M; Mitchell, Jamie A
2018-04-02
Goal-striving stress refers to the psychological consequences of seeking but failing to reach upward mobility and is more common among low-income and people of color. Intergenerational mobility-or improved socioeconomic standing relative to one's parents-may be an important predictor of goal-striving stress for Blacks. We used the National Survey of American Life to investigate the association between intergenerational mobility and goal-striving stress among U.S.-born African Americans, U.S.-born Caribbean Blacks, and foreign-born Caribbean Blacks. Intergenerational mobility was associated with lower goal-striving stress and U.S.-born African Americans and Caribbean Blacks reported lower goal-striving stress than foreign-born Caribbean Blacks. Goal-striving stress was relatively high among foreign-born Blacks, regardless of level of intergenerational mobility attained. Goal-striving is an important stressor for foreign-born Caribbean Blacks, regardless of their level of educational success. Given increasing Black migration, future studies should disaggregate the Black racial category based on ethnicity and nativity.
The black gender gap in educational attainment: historical trends and racial comparisons.
McDaniel, Anne; DiPrete, Thomas A; Buchmann, Claudia; Shwed, Uri
2011-08-01
It is often asserted that the gender gap in educational attainment is larger for blacks than whites, but historical trends comparing the black and white gender gap have received surprisingly little attention. Analysis of historical data from the U.S. census IPUMS samples shows that the gender gap in college completion has evolved differently for whites and blacks. Historically, the female advantage in educational attainment among blacks is linked to more favorable labor market opportunities and stronger incentives for employment for educated black women. Blacks, particularly black males, still lag far behind whites in their rates of college completion, but the striking educational gains of white women have caused the racial patterns of gender differences in college completion rates to grow more similar over time. While some have linked the disadvantaged position of black males to their high risk of incarceration, our estimates suggest that incarceration has a relatively small impact on the black gender gap and the racial gap in college completion rates for males in the United States.
NASA Astrophysics Data System (ADS)
Zhang, Baocheng; Cai, Qing-yu; Zhan, Ming-sheng; You, Li
2011-02-01
We revisit in detail the paradox of black hole information loss due to Hawking radiation as tunneling. We compute the amount of information encoded in correlations among Hawking radiations for a variety of black holes, including the Schwarzchild black hole, the Reissner-Nordström black hole, the Kerr black hole, and the Kerr-Newman black hole. The special case of tunneling through a quantum horizon is also considered. Within a phenomenological treatment based on the accepted emission probability spectrum from a black hole, we find that information is leaked out hidden in the correlations of Hawking radiation. The recovery of this previously unaccounted for information helps to conserve the total entropy of a system composed of a black hole plus its radiations. We thus conclude, irrespective of the microscopic picture for black hole collapsing, the associated radiation process: Hawking radiation as tunneling, is consistent with unitarity as required by quantum mechanics.
Kong, Xiang-Peng; Shen, Xiaomei; Jang, Joonkyung; Gao, Xingfa
2018-03-01
The electronic and optical properties of black phosphorus (black-P) are significantly modulated by fabricating the edges of this two-dimensional material. Electron lone pairs (ELPs) are ubiquitous in black-P, but their role in creating the edge effects of black-P is poorly understood. Using first-principle calculations, we report ELPs of black-P experience severe Coulomb repulsion and play a central role in creating the edge effects of black-P. We discover the outermost P atoms of the zigzag edges of black-PQDs are free of the Coulomb repulsion, but the P atoms of the armchair edges do experience the Coulomb repulsion. The Coulomb repulsion serves as a new chemical driving force to make electron donor-acceptor bonds with chemical groups bearing vacant orbitals. Our results provide insights into the mechanism responsible for the peculiar edge effects of black-P and highlight the opportunity to use the ELPs of black-P for their damage-free surface functionalization.
Pyrolytic carbon coated black silicon
Shah, Ali; Stenberg, Petri; Karvonen, Lasse; Ali, Rizwan; Honkanen, Seppo; Lipsanen, Harri; Peyghambarian, N.; Kuittinen, Markku; Svirko, Yuri; Kaplas, Tommi
2016-01-01
Carbon is the most well-known black material in the history of man. Throughout the centuries, carbon has been used as a black material for paintings, camouflage, and optics. Although, the techniques to make other black surfaces have evolved and become more sophisticated with time, carbon still remains one of the best black materials. Another well-known black surface is black silicon, reflecting less than 0.5% of incident light in visible spectral range but becomes a highly reflecting surface in wavelengths above 1000 nm. On the other hand, carbon absorbs at those and longer wavelengths. Thus, it is possible to combine black silicon with carbon to create an artificial material with very low reflectivity over a wide spectral range. Here we report our results on coating conformally black silicon substrate with amorphous pyrolytic carbon. We present a superior black surface with reflectance of light less than 0.5% in the spectral range of 350 nm to 2000 nm. PMID:27174890
ERIC Educational Resources Information Center
Dantzler, Dolores J.
The purposes of the study were to determine the extent to which basal readers contain stories pertaining to blacks; to find out if the racial implications stated in basal texts are those that blacks want; to locate the black heroes in basal readers and evaluate whether or not these are the preferred heroes of the population of blacks sampled in…
ERIC Educational Resources Information Center
Dimas, Chris
The purpose of this study was to determine the effects of motion pictures utilizing black models on the self-concept of black fourth and sixth grade students; that perhaps, mediated black models may be effective in bringing about a more positive self-concept among black students. The design of this study was of the post-test form only. This was…
40 CFR 458.10 - Applicability; description of the carbon black furnace process subcategory.
Code of Federal Regulations, 2010 CFR
2010-07-01
... carbon black furnace process subcategory. 458.10 Section 458.10 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS CARBON BLACK MANUFACTURING POINT SOURCE CATEGORY Carbon Black Furnace Process Subcategory § 458.10 Applicability; description of the carbon black...
40 CFR 458.20 - Applicability: description of the carbon black thermal process subcategory.
Code of Federal Regulations, 2010 CFR
2010-07-01
... carbon black thermal process subcategory. 458.20 Section 458.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS CARBON BLACK MANUFACTURING POINT SOURCE CATEGORY Carbon Black Thermal Process Subcategory § 458.20 Applicability: description of the carbon black...
40 CFR 458.30 - Applicability; description of the carbon black channel process subcategory.
Code of Federal Regulations, 2010 CFR
2010-07-01
... carbon black channel process subcategory. 458.30 Section 458.30 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS CARBON BLACK MANUFACTURING POINT SOURCE CATEGORY Carbon Black Channel Process Subcategory § 458.30 Applicability; description of the carbon black...
EVALUATION OF CARBON BLACK SLURRIES AS CLEAN BURNING FUELS
Experiments were performed to examine the pumpability, atomization and combustion characteristics of slurries made of mixtures of carbon black with No. 2 fuel oil and methanol. Carbon black-No. 2 fuel oil and carbon black-methanol slurries, with carbon black contents of up to 50 ...
77 FR 77070 - Black Bear Hydro Partners, LLC;
Federal Register 2010, 2011, 2012, 2013, 2014
2012-12-31
... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 2727-086] Black Bear Hydro...: October 24, 2012. d. Submitted By: Black Bear Hydro Partners, LLC (Black Bear Hydro). e. Name of Project... designating Black Bear Hydro as the Commission's non-federal representative for carrying out informal...
Black Managers in White Corporations.
ERIC Educational Resources Information Center
Fernandez, John P.
The study examines the major determinants of the career patterns of black managers in white businesses and the effects of corporations on their black managers' identities and relationships to the black community. Analyzed were occupational mobility theories; white and black managers' career patterns, goals, and related factors; company employment…
ERIC Educational Resources Information Center
Journal of Blacks in Higher Education, 1999
1999-01-01
Presents a collection of articles that offer information on such issues as the progress of black student matriculations at the highest-ranking U.S. colleges; black historians teaching black history; Blacks in academic accounting; banishing the stereotype that African Americans cannot do mathematics; campus crime rates at black colleges; and the…
The Making of the Black Middle Class.
ERIC Educational Resources Information Center
Collins, Sharon M.
1983-01-01
Examines Black occupational mobility and factors that have influenced the growth of the Black middle class since the 1960s. Argues that the Black middle class occupies a fragile market position because Black mobility depends on fluctuating government policy rather than on free market factors. (Author/MJL)
Black Popular Music: First Scorned, Then Copied and Admired.
ERIC Educational Resources Information Center
Jones, Regina; Spiegelman, Judy
1991-01-01
Black popular music has its roots in African music that was a way of preserving history. A brief social and cultural history traces black popular music in the United States, focusing on the music blacks listened to, rather than just the music blacks played. (SLD)
Understanding the Black Aesthetic Experience.
ERIC Educational Resources Information Center
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…
Personality Characteristics of Black Youth: A Cross-Cultural Investigation.
ERIC Educational Resources Information Center
Jones, Enrico E.
1979-01-01
Black adolescent girls of low socioeconomic status described themselves more favorably on the Adjective Check List than did Black and White middle-class adolescents. American and Jamaican Blacks described themselves similarly and differed similarly from White American conterparts, supporting the influence of a common cultural heritage for Blacks.…
Building Better Narratives in Black Education
ERIC Educational Resources Information Center
Anderson, Meredith B. L.
2016-01-01
"Building Better Narratives in Black Education" fundamentally changes the narrative and face of education reform to meaningfully include Black voices, leaders and initiatives that truly have equity and Black student success at the core. This is imperative as there is an education crisis for Black students in the United States. Recent…
New Directions for Black Women?
ERIC Educational Resources Information Center
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…
"Nothing Has Stopped Me. I Keep Going:" Black Gay Narratives
ERIC Educational Resources Information Center
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…
50 CFR 648.142 - Black sea bass specifications.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 50 Wildlife and Fisheries 12 2012-10-01 2012-10-01 false Black sea bass specifications. 648.142... Measures for the Black Sea Bass Fishery § 648.142 Black sea bass specifications. (a) Commercial quota, recreational landing limit, research set-aside, and other specification measures. The Black Sea Bass Monitoring...
50 CFR 648.142 - Black sea bass specifications.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Black sea bass specifications. 648.142... Measures for the Black Sea Bass Fishery § 648.142 Black sea bass specifications. (a) Commercial quota, recreational landing limit, research set-aside, and other specification measures. The Black Sea Bass Monitoring...
50 CFR 648.142 - Black sea bass specifications.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Black sea bass specifications. 648.142... Measures for the Black Sea Bass Fishery § 648.142 Black sea bass specifications. (a) Commercial quota, recreational landing limit, research set-aside, and other specification measures. The Black Sea Bass Monitoring...
Black on Yellow: Afro-Americans View Chinese-Americans, 1850-1935
ERIC Educational Resources Information Center
Shankman, Arnold
1978-01-01
Using data collected from black newspapers, an explanation is sought for the unfavorable stereotypes blacks have held about Chinese Americans. Economic competition, cultural and religious differences, and blacks' belief that the Chinese were prejudiced against them are some of the historical factors mentioned which influenced black attitudes…
Census Undercount and the Undercount of the Black Population.
ERIC Educational Resources Information Center
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…
ERIC Educational Resources Information Center
Bell, Edward Earl
2010-01-01
Background: The graduation numbers for Black males are dismal, chilling, and undeniably pathetic. The nation graduates only 47% of Black males who enter the 9th grade. The infusion of federal dollars and philanthropic support will not stop the trajectory of Black males who drop out of school. Black males face an upheaval educational battle;…
78 FR 70297 - Combined Notice of Filings #1
Federal Register 2010, 2011, 2012, 2013, 2014
2013-11-25
.... Applicants: Black Bear Hydro Partners, LLC, Black Bear Development Holdings, LLC, Black Bear SO, LLC, Black Bear Holding LLC. Description: Joint Application for Authorization Under Section 203 of Black Bear...: 20131114-5164. Comments Due: 5 p.m. ET 12/5/13. Docket Numbers: ER14-407-000. Applicants: Capacity Markets...
ERIC Educational Resources Information Center
Brown, Angela Khristin
2013-01-01
The migration of blacks in North America through slavery became united. The population of blacks passed down 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…
Meditation on Tuskegee: Black Studies Stories and Their Imbrication.
ERIC Educational Resources Information Center
Baker, Houston A., Jr.
1995-01-01
Discusses today's black studies programs and the division between the empiricist and conceptualist views of black history. Through a personal narrative involving a visit to Tuskegee University, the author muses over Booker T. Washington's type of eloquence in addressing the black experience compared to today's black public intellectual's attempts,…
Institutionalized Racism and the Education of Blacks
ERIC Educational Resources Information Center
Spears, Arthur K.
1978-01-01
Research into the causes of the unsatisfactory educational performance of many black students has focused on linguistic and cultural differences of blacks. Institutionalized racism, however, should be recognized as the major factor affecting black academic achievement. Black students should not be evaluated by the same criteria as white students.…
eBlack Studies: A Twenty-First-Century Challenge.
ERIC Educational Resources Information Center
Alkalimat, Abdul
2000-01-01
Calls for the transformation of black studies that moves from ideology to information. Argues that eBlack, the virtualization of the black experience, is the basis for the next stage of this academic discipline. Presents three theoretical principles of eBlack studies (cyberdemocracy, collective intelligence, and information freedom); describes…
Soul Music: Techniques for Therapeutic Intervention
ERIC Educational Resources Information Center
Toldson, Ivory L.; Pasteur, Alfred B.
1972-01-01
The authors conclude that using black music in the educational process aligns educational input with black culture. This approach, which extends and utilizes the spiritual dimension of black life, is consistent with the black value system and can help black learners integrate and internalize an aspect of their cultural heritage. (Author/BY)
Black Entrepreneurship in America.
ERIC Educational Resources Information Center
Green, Shelley; Pryde, Paul
The economic condition of black Americans is discussed, proceeding from the assumption that black economic progress does not depend on a renewed struggle for unobtained civil rights, but rather on the creative response of black Americans to economic opportunity and problems. In the long run, black economic development must rely on the…
The State of Black America 1987.
ERIC Educational Resources Information Center
Dewart, Janet, Ed.
This book consists of 12 papers on current issues affecting black Americans. Titles (and authors) are the following: (1) "Black America 1986: An Overview" (John E. Jacob); (2) "The Law and Black Americans: Retreat from Civil Rights" (Julius L. Chambers); (3) "Taking Charge: An Approach to Making the Educational Problems of Blacks Comprehensible…
Martin Robison Delany (1812-1885): physician, black separatist, explorer, soldier.
Rosenfeld, L
1989-09-01
Martin Robison Delany's great contribution to American life and black history stems from his defiant blackness. He was America's first "Black Nationalist" and the intense embodiment of black pride. Ever changing in his career, he always identified with the black experience and its place in history. In an active life he was doctor, dentist, orator, editor, publisher, Harvard medical student, explorer, dabbler in Central American politics, army officer, and Reconstruction office seeker.
ERIC Educational Resources Information Center
Johnson, Audreye E., Ed.
This publication consists of the proceedings of a workshop on the social, cultural, and economic experiences of Blacks. The workshops' goals were to intensify the interest of social workers in the Black experience; to examine the values which have an impact on services to Black people; to increase the knowledge of social workers about Blacks; and…
Accretion onto some well-known regular black holes
NASA Astrophysics Data System (ADS)
Jawad, Abdul; Shahzad, M. Umair
2016-03-01
In this work, we discuss the accretion onto static spherically symmetric regular black holes for specific choices of the equation of state parameter. The underlying regular black holes are charged regular black holes using the Fermi-Dirac distribution, logistic distribution, nonlinear electrodynamics, respectively, and Kehagias-Sftesos asymptotically flat regular black holes. We obtain the critical radius, critical speed, and squared sound speed during the accretion process near the regular black holes. We also study the behavior of radial velocity, energy density, and the rate of change of the mass for each of the regular black holes.
Enhanced performance of VOx-based bolometer using patterned gold black absorber
NASA Astrophysics Data System (ADS)
Smith, Evan M.; Panjwani, Deep; Ginn, James; Warren, Andrew; Long, Christopher; Figuieredo, Pedro; Smith, Christian; Perlstein, Joshua; Walter, Nick; Hirschmugl, Carol; Peale, Robert E.; Shelton, David J.
2015-06-01
Patterned highly absorbing gold black film has been selectively deposited on the active surfaces of a vanadium-oxide-based infrared bolometer array. Patterning by metal lift-off relies on protection of the fragile gold black with an evaporated oxide, which preserves gold black's near unity absorption. This patterned gold black also survives the dry-etch removal of the sacrificial polyimide used to fabricate the air-bridge bolometers. Infrared responsivity is substantially improved by the gold black coating without significantly increasing noise. The increase in the time constant caused by the additional mass of gold black is a modest 14%.
The weapon focus effect is weaker with Black versus White male perpetrators.
Pickel, Kerri L; Sneyd, Danielle E
2018-01-01
We compared the influence of a weapon's presence on eyewitnesses' memory for a White versus a Black male perpetrator. Prior data indicate that unusual objects in visual scenes attract attention and that a weapon's effect depends on how unusual it seems within the context in which it appears. Therefore, given the stereotype linking Black men and weapons, we predicted a weaker weapon focus effect with the Black perpetrator. The results of Experiment 1 supported this hypothesis using White and Black witnesses. Moreover, in Experiment 2 the weapon focus effect became nonsignificant when the Black perpetrator wore a style of clothing that is strongly associated with Black men. We propose that observing an armed Black perpetrator automatically activates a stereotype linking Black men with weapons and crime, which in turn reduces the perceived unusualness of the weapon and thus its ability to attract attention.
The fragmentation instability of a black hole with f( R) global monopole under GUP
NASA Astrophysics Data System (ADS)
Chen, Lingshen; Cheng, Hongbo
2018-03-01
Having studied the fragmentation of the black holes containing f( R) global monopole under the generalized uncertainty principle (GUP), we show the influences from this kind of monopole, f( R) theory, and GUP on the evolution of black holes. We focus on the possibility that the black hole breaks into two parts by means of the second law of thermodynamics. We derive the entropies of the initial black hole and the broken parts while the generalization of Heisenberg's uncertainty principle is introduced. We find that the f( R) global monopole black hole keeps stable instead of splitting without the generalization because the entropy difference is negative. The fragmentation of the black hole will happen if the black hole entropies are limited by the GUP and the considerable deviation from the general relativity leads to the case that the mass of one fragmented black hole is smaller and the other one's mass is larger.
Novel platinum black electroplating technique improving mechanical stability.
Kim, Raeyoung; Nam, Yoonkey
2013-01-01
Platinum black microelectrodes are widely used as an effective neural signal recording sensor. The simple fabrication process, high quality signal recording and proper biocompatibility are the main advantages of platinum black microelectrodes. When microelectrodes are exposed to actual biological system, various physical stimuli are applied. However, the porous structure of platinum black is vulnerable to external stimuli and destroyed easily. The impedance level of the microelectrode increases when the microelectrodes are damaged resulting in decreased recording performance. In this study, we developed mechanically stable platinum black microelectrodes by adding polydopamine. The polydopamine layer was added between the platinum black structures by electrodeposition method. The initial impedance level of platinum black only microelectrodes and polydopamine added microelectrodes were similar but after applying ultrasonication the impedance value dramatically increased for platinum black only microelectrodes, whereas polydopamine added microelectrodes showed little increase which were nearly retained initial values. Polydopamine added platinum black microelectrodes are expected to extend the availability as neural sensors.
Soft hair of dynamical black hole and Hawking radiation
NASA Astrophysics Data System (ADS)
Chu, Chong-Sun; Koyama, Yoji
2018-04-01
Soft hair of black hole has been proposed recently to play an important role in the resolution of the black hole information paradox. Recent work has emphasized that the soft modes cannot affect the black hole S-matrix due to Weinberg soft theorems. However as soft hair is generated by supertranslation of geometry which involves an angular dependent shift of time, it must have non-trivial quantum effects. We consider supertranslation of the Vaidya black hole and construct a non-spherical symmetric dynamical spacetime with soft hair. We show that this spacetime admits a trapping horizon and is a dynamical black hole. We find that Hawking radiation is emitted from the trapping horizon of the dynamical black hole. The Hawking radiation has a spectrum which depends on the soft hair of the black hole and this is consistent with the factorization property of the black hole S-matrix.
Entropy of black holes with multiple horizons
NASA Astrophysics Data System (ADS)
He, Yun; Ma, Meng-Sen; Zhao, Ren
2018-05-01
We examine the entropy of black holes in de Sitter space and black holes surrounded by quintessence. These black holes have multiple horizons, including at least the black hole event horizon and a horizon outside it (cosmological horizon for de Sitter black holes and "quintessence horizon" for the black holes surrounded by quintessence). Based on the consideration that the two horizons are not independent each other, we conjecture that the total entropy of these black holes should not be simply the sum of entropies of the two horizons, but should have an extra term coming from the correlations between the two horizons. Different from our previous works, in this paper we consider the cosmological constant as the variable and employ an effective method to derive the explicit form of the entropy. We also try to discuss the thermodynamic stabilities of these black holes according to the entropy and the effective temperature.
BlackMax: A black-hole event generator with rotation, recoil, split branes, and brane tension
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dai Dechang; Starkman, Glenn; Stojkovic, Dejan
2008-04-01
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 bemore » interfaced with Herwig and Pythia. The main code can be downloaded from http://www-pnp.physics.ox.ac.uk/{approx}issever/BlackMax/blackmax.html.« less
Black hole and cosmos with multiple horizons and multiple singularities in vector-tensor theories
NASA Astrophysics Data System (ADS)
Gao, Changjun; Lu, Youjun; Yu, Shuang; Shen, You-Gen
2018-05-01
A stationary and spherically symmetric black hole (e.g., Reissner-Nordström black hole or Kerr-Newman black hole) has, at most, one singularity and two horizons. One horizon is the outer event horizon and the other is the inner Cauchy horizon. Can we construct static and spherically symmetric black hole solutions with N horizons and M singularities? The de Sitter cosmos has only one apparent horizon. Can we construct cosmos solutions with N horizons? In this article, we present the static and spherically symmetric black hole and cosmos solutions with N horizons and M singularities in the vector-tensor theories. Following these motivations, we also construct the black hole solutions with a firewall. The deviation of these black hole solutions from the usual ones can be potentially tested by future measurements of gravitational waves or the black hole continuum spectrum.
Evolution of perturbations of squashed Kaluza-Klein black holes: Escape from instability
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ishihara, Hideki; Kimura, Masashi; Konoplya, Roman A.
2008-04-15
The squashed Kaluza-Klien (KK) black holes differ from the Schwarzschild black holes with asymptotic flatness or the black strings even at energies for which the KK modes are not excited yet, so that squashed KK black holes open a window in higher dimensions. Another important feature is that the squashed KK black holes are apparently stable and, thereby, let us avoid the Gregory-Laflamme instability. In the present paper, the evolution of scalar and gravitational perturbations in time and frequency domains is considered for these squashed KK black holes. The scalar field perturbations are analyzed for general rotating squashed KK blackmore » holes. Gravitational perturbations for the so-called zero mode are shown to be decayed for nonrotating black holes, in concordance with the stability of the squashed KK black holes. The correlation of quasinormal frequencies with the size of extra dimension is discussed.« less
Thermodynamic studies of different black holes with modifications of entropy
NASA Astrophysics Data System (ADS)
Haldar, Amritendu; Biswas, Ritabrata
2018-02-01
In recent years, the thermodynamic properties of black holes are topics of interests. We investigate the thermodynamic properties like surface gravity and Hawking temperature on event horizon of regular black holes viz. Hayward Class and asymptotically AdS (Anti-de Sitter) black holes. We also analyze the thermodynamic volume and naive geometric volume of asymptotically AdS black holes and show that the entropy of these black holes is simply the ratio of the naive geometric volume to thermodynamic volume. We plot the different graphs and interpret them physically. We derive the `cosmic-Censorship-Inequality' for both type of black holes. Moreover, we calculate the thermal heat capacity of aforesaid black holes and study their stabilities in different regimes. Finally, we compute the logarithmic correction to the entropy for both the black holes considering the quantum fluctuations around the thermal equilibrium and study the corresponding thermodynamics.
The use of trivalent chromium bath to obtain a solar selective black chromium coating
NASA Astrophysics Data System (ADS)
Survilienė, S.; Češūnienė, A.; Juškėnas, R.; Selskienė, A.; Bučinskienė, D.; Kalinauskas, P.; Juškevičius, K.; Jurevičiūtė, I.
2014-06-01
Black chromium coatings were electrodeposited from a trivalent chromium bath using a ZnO additive as a second main component. Black chromium was electrodeposited on steel and copper plates and substrates plated with bright nickel prior to black chromium electrodeposition. The black chromium coatings were characterized by XRD and SEM. The XRD data suggest that the phase structure of black chromium may be defined as a zinc solid solution in chromium or a chromium solid solution in zinc depending on the chromium/zinc ratio in the deposit. The role of substrate finish was evaluated through the corrosion resistance and reflectance of black chromium. According to corrosion tests the samples plated with bright nickel prior to black chromium deposition have shown the highest corrosion resistance. The electrodeposited black chromium possesses good optical properties for the absorption of solar energy. The absorption coefficient of black chromium was found to be over 0.99 for the samples obtained without the Ni undercoat and below 0.99 for those obtained with the use of Ni undercoat. However, the use of nickel undercoat before black chromium plating is recommended because it remarkably improves the corrosion resistance of samples.
Gravitational tension, spacetime pressure and black hole volume
NASA Astrophysics Data System (ADS)
Armas, Jay; Obers, Niels A.; Sanchioni, Marco
2016-09-01
We study the first law of black hole thermodynamics in the presence of surrounding gravitational fields and argue that variations of these fields are naturally incorporated in the first law by defining gravitational tension or gravitational binding energy. We demonstrate that this notion can also be applied in Anti-de Sitter spacetime, in which the surrounding gravitational field is sourced by a cosmological fluid, therefore showing that spacetime volume and gravitational tension encode the same physics as spacetime pressure and black hole volume. We furthermore show that it is possible to introduce a definition of spacetime pressure and black hole volume for any spacetime with characteristic length scales which does not necessarily require a cosmological constant sourcing Einstein equations. However, we show that black hole volume is non-universal in the flat spacetime limit, questioning its significance. We illustrate these ideas by studying the resulting black hole volume of Kaluza-Klein black holes and of a toy model for a black hole binary system in five spacetime dimensions (the black saturn solution) as well as of several novel perturbative black hole solutions. These include the higher-dimensional Kerr-Newman solution in Anti-de Sitter spacetime as well as other black holes in plane wave and Lifshitz spacetimes.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang Baocheng; Graduate University of Chinese Academy of Sciences, Beijing 100049; Cai Qingyu, E-mail: qycai@wipm.ac.cn
2011-02-15
Research Highlights: > Information is found to be encoded and carried away by Hawking radiations. > Entropy is conserved in Hawking radiation. > We thus conclude no information is lost. > The dynamics of black hole may be unitary. - Abstract: We revisit in detail the paradox of black hole information loss due to Hawking radiation as tunneling. We compute the amount of information encoded in correlations among Hawking radiations for a variety of black holes, including the Schwarzchild black hole, the Reissner-Nordstroem black hole, the Kerr black hole, and the Kerr-Newman black hole. The special case of tunneling throughmore » a quantum horizon is also considered. Within a phenomenological treatment based on the accepted emission probability spectrum from a black hole, we find that information is leaked out hidden in the correlations of Hawking radiation. The recovery of this previously unaccounted for information helps to conserve the total entropy of a system composed of a black hole plus its radiations. We thus conclude, irrespective of the microscopic picture for black hole collapsing, the associated radiation process: Hawking radiation as tunneling, is consistent with unitarity as required by quantum mechanics.« less
Structure of Black Male Students Academic Achievement in Science
NASA Astrophysics Data System (ADS)
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.
Big Black Holes Mean Bad News for Stars (diagram)
NASA Technical Reports Server (NTRS)
2006-01-01
[figure removed for brevity, see original site] Poster Version Suppression of Star Formation from Supermassive Black Holes This diagram illustrates research from NASA's Galaxy Evolution Explorer showing that black holes -- once they reach a critical size -- can put the brakes on new star formation in elliptical galaxies. In this graph, galaxies and their supermassive black holes are indicated by the drawings (the black circle at the center of each galaxy represents the black hole). The relative masses of the galaxies and their black holes are reflected in the sizes of the drawings. Blue indicates that the galaxy has new stars, while red means the galaxy does not have any detectable new stars. The Galaxy Evolution Explorer observed the following trend: the biggest galaxies and black holes (shown in upper right corner) are more likely to have no observable star formation (red) than the smaller galaxies with smaller black holes. This is evidence that black holes can create environments unsuitable for stellar birth. The white line in the diagram illustrates that, for any galaxy no matter what the mass, its black hole must reach a critical size before it can shut down star formation.Bird specimens track 135 years of atmospheric black carbon and environmental policy
NASA Astrophysics Data System (ADS)
DuBay, Shane G.; Fuldner, Carl C.
2017-10-01
Atmospheric black carbon has long been recognized as a public health and environmental concern. More recently, black carbon has been identified as a major, ongoing contributor to anthropogenic climate change, thus making historical emission inventories of black carbon an essential tool for assessing past climate sensitivity and modeling future climate scenarios. Current estimates of black carbon emissions for the early industrial era have high uncertainty, however, because direct environmental sampling is sparse before the mid-1950s. Using photometric reflectance data of >1,300 bird specimens drawn from natural history collections, we track relative ambient concentrations of atmospheric black carbon between 1880 and 2015 within the US Manufacturing Belt, a region historically reliant on coal and dense with industry. Our data show that black carbon levels within the region peaked during the first decade of the 20th century. Following this peak, black carbon levels were positively correlated with coal consumption through midcentury, after which they decoupled, with black carbon concentrations declining as consumption continued to rise. The precipitous drop in atmospheric black carbon at midcentury reflects policies promoting burning efficiency and fuel transitions rather than regulating emissions alone. Our findings suggest that current emission inventories based on predictive modeling underestimate levels of atmospheric black carbon for the early industrial era, suggesting that the contribution of black carbon to past climate forcing may also be underestimated. These findings build toward a spatially dynamic emission inventory of black carbon based on direct environmental sampling.
Risky movies, risky behaviors, and ethnic identity among Black adolescents.
Bleakley, Amy; Ellithorpe, Morgan E; Hennessy, Michael; Jamieson, Patrick E; Khurana, Atika; Weitz, Ilana
2017-12-01
To investigate how exposure to sex, alcohol and violent content in mainstream and Black-oriented movies relates to corresponding adolescent behavior among Black youth from the United States and whether those relationships are moderated by ethnic identity. The present study uses survey data from an online sample of 1000 Black adolescents and content analysis ratings on top-grossing 2014 films and 2013/2014 Black-oriented films. Content-specific exposure measures for alcohol, sexual activity, and violence were calculated from self-reported exposure data and content analysis ratings. Regression analyses estimated the associations among exposures to risky health content in mainstream and Black-oriented films and adolescent behaviors as well as moderation by ethnic group identity. Black adolescents were mostly unaffected by exposure to risk portrayals in mainstream films, but exposure to risk in Black-oriented films was related to their behavior in all three domains. Strong group identity strengthened the relationship between exposure to sex in Black-oriented and mainstream films depending on the sexual outcome. The type of movie (i.e., mainstream or Black-oriented) through which Black adolescents are exposed to risky health portrayals is important for understanding its relationship to their behavior, and variations by ethnic identity were limited to sex content. Future research should identify the mechanisms through which risk content in Black-oriented films is associated with Black adolescents' risky behaviors to determine how media influence contributes to behavioral disparities among youth. Copyright © 2017 Elsevier Ltd. All rights reserved.
Bird specimens track 135 years of atmospheric black carbon and environmental policy
DuBay, Shane G.; Fuldner, Carl C.
2017-01-01
Atmospheric black carbon has long been recognized as a public health and environmental concern. More recently, black carbon has been identified as a major, ongoing contributor to anthropogenic climate change, thus making historical emission inventories of black carbon an essential tool for assessing past climate sensitivity and modeling future climate scenarios. Current estimates of black carbon emissions for the early industrial era have high uncertainty, however, because direct environmental sampling is sparse before the mid-1950s. Using photometric reflectance data of >1,300 bird specimens drawn from natural history collections, we track relative ambient concentrations of atmospheric black carbon between 1880 and 2015 within the US Manufacturing Belt, a region historically reliant on coal and dense with industry. Our data show that black carbon levels within the region peaked during the first decade of the 20th century. Following this peak, black carbon levels were positively correlated with coal consumption through midcentury, after which they decoupled, with black carbon concentrations declining as consumption continued to rise. The precipitous drop in atmospheric black carbon at midcentury reflects policies promoting burning efficiency and fuel transitions rather than regulating emissions alone. Our findings suggest that current emission inventories based on predictive modeling underestimate levels of atmospheric black carbon for the early industrial era, suggesting that the contribution of black carbon to past climate forcing may also be underestimated. These findings build toward a spatially dynamic emission inventory of black carbon based on direct environmental sampling. PMID:29073051
Two stellar-mass black holes in the globular cluster M22.
Strader, Jay; Chomiuk, Laura; Maccarone, Thomas J; Miller-Jones, James C A; Seth, Anil C
2012-10-04
Hundreds of stellar-mass black holes probably form in a typical globular star cluster, with all but one predicted to be ejected through dynamical interactions. Some observational support for this idea is provided by the lack of X-ray-emitting binary stars comprising one black hole and one other star ('black-hole/X-ray binaries') in Milky Way globular clusters, even though many neutron-star/X-ray binaries are known. Although a few black holes have been seen in globular clusters around other galaxies, the masses of these cannot be determined, and some may be intermediate-mass black holes that form through exotic mechanisms. Here we report the presence of two flat-spectrum radio sources in the Milky Way globular cluster M22, and we argue that these objects are black holes of stellar mass (each ∼10-20 times more massive than the Sun) that are accreting matter. We find a high ratio of radio-to-X-ray flux for these black holes, consistent with the larger predicted masses of black holes in globular clusters compared to those outside. The identification of two black holes in one cluster shows that ejection of black holes is not as efficient as predicted by most models, and we argue that M22 may contain a total population of ∼5-100 black holes. The large core radius of M22 could arise from heating produced by the black holes.
An intermediate-mass black hole in the centre of the globular cluster 47 Tucanae.
Kızıltan, Bülent; Baumgardt, Holger; Loeb, Abraham
2017-02-08
Intermediate-mass black holes should help us to understand the evolutionary connection between stellar-mass and super-massive black holes. However, the existence of intermediate-mass black holes is still uncertain, and their formation process is therefore unknown. It has long been suspected that black holes with masses 100 to 10,000 times that of the Sun should form and reside in dense stellar systems. Therefore, dedicated observational campaigns have targeted globular clusters for many decades, searching for signatures of these elusive objects. All candidate signatures appear radio-dim and do not have the X-ray to radio flux ratios required for accreting black holes. Based on the lack of an electromagnetic counterpart, upper limits of 2,060 and 470 solar masses have been placed on the mass of a putative black hole in 47 Tucanae (NGC 104) from radio and X-ray observations, respectively. Here we show there is evidence for a central black hole in 47 Tucanae with a mass of solar masses when the dynamical state of the globular cluster is probed with pulsars. The existence of an intermediate-mass black hole in the centre of one of the densest clusters with no detectable electromagnetic counterpart suggests that the black hole is not accreting at a sufficient rate to make it electromagnetically bright and therefore, contrary to expectations, is gas-starved. This intermediate-mass black hole might be a member of an electromagnetically invisible population of black holes that grow into supermassive black holes in galaxies.
Jones, Claire E L; Maben, Jill; Lucas, Grace; Davies, Elizabeth A; Jack, Ruth H; Ream, Emma
2015-03-13
Understanding barriers to early diagnosis of symptomatic breast cancer among Black African, Black Caribbean and White British women in the UK. In-depth qualitative interviews using grounded theory methods to identify themes. Findings validated through focus groups. 94 women aged 33-91 years; 20 Black African, 20 Black Caribbean and 20 White British women diagnosed with symptomatic breast cancer were interviewed. Fourteen Black African and 20 Black Caribbean women with (n=19) and without (n=15) breast cancer participated in six focus groups. Eight cancer centres/hospital trusts in London (n=5), Somerset (n=1), West Midlands (n=1) and Greater Manchester (n=1) during 2012-2013. There are important differences and similarities in barriers to early diagnosis of breast cancer between Black African, Black Caribbean and White British women in the UK. Differences were influenced by country of birth, time spent in UK and age. First generation Black African women experienced most barriers and longest delays. Second generation Black Caribbean and White British women were similar and experienced fewest barriers. Absence of pain was a barrier for Black African and Black Caribbean women. Older White British women (≥70 years) and first generation Black African and Black Caribbean women shared conservative attitudes and taboos about breast awareness. All women viewed themselves at low risk of the disease, and voiced uncertainty over breast awareness and appraising non-lump symptoms. Focus group findings validated and expanded themes identified in interviews. Findings challenged reporting of Black women homogenously in breast cancer research. This can mask distinctions within and between ethnic groups. Current media and health promotion messages need reframing to promote early presentation with breast symptoms. Working with communities and developing culturally appropriate materials may lessen taboos and stigma, raise awareness, increase discussion of breast cancer and promote prompt help-seeking for breast symptoms among women with low cancer awareness. 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.
Jones, Claire E L; Maben, Jill; Lucas, Grace; Davies, Elizabeth A; Jack, Ruth H; Ream, Emma
2015-01-01
Objectives Understanding barriers to early diagnosis of symptomatic breast cancer among Black African, Black Caribbean and White British women in the UK. Design In-depth qualitative interviews using grounded theory methods to identify themes. Findings validated through focus groups. Participants 94 women aged 33–91 years; 20 Black African, 20 Black Caribbean and 20 White British women diagnosed with symptomatic breast cancer were interviewed. Fourteen Black African and 20 Black Caribbean women with (n=19) and without (n=15) breast cancer participated in six focus groups. Setting Eight cancer centres/hospital trusts in London (n=5), Somerset (n=1), West Midlands (n=1) and Greater Manchester (n=1) during 2012–2013. Results There are important differences and similarities in barriers to early diagnosis of breast cancer between Black African, Black Caribbean and White British women in the UK. Differences were influenced by country of birth, time spent in UK and age. First generation Black African women experienced most barriers and longest delays. Second generation Black Caribbean and White British women were similar and experienced fewest barriers. Absence of pain was a barrier for Black African and Black Caribbean women. Older White British women (≥70 years) and first generation Black African and Black Caribbean women shared conservative attitudes and taboos about breast awareness. All women viewed themselves at low risk of the disease, and voiced uncertainty over breast awareness and appraising non-lump symptoms. Focus group findings validated and expanded themes identified in interviews. Conclusions Findings challenged reporting of Black women homogenously in breast cancer research. This can mask distinctions within and between ethnic groups. Current media and health promotion messages need reframing to promote early presentation with breast symptoms. Working with communities and developing culturally appropriate materials may lessen taboos and stigma, raise awareness, increase discussion of breast cancer and promote prompt help-seeking for breast symptoms among women with low cancer awareness. PMID:25770231
NASA Observatory Confirms Black Hole Limits
NASA Astrophysics Data System (ADS)
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 time, the ones in between have been counted properly. Growth of the Biggest Black Holes Illustrated Growth of the Biggest Black Holes Illustrated "We need to have an accurate head count over time of all growing black holes if we ever hope to understand their habits, so to speak," co-author Richard Mushotzky of NASA's Goddard Space Flight Center in Greenbelt, Md. Supermassive black holes themselves are invisible, but heated gas around them -- some of which will eventually fall into the black hole - produces copious amounts of radiation in the centers of galaxies as the black holes grow. Growth of the Biggest Black Holes Illustrated Growth of Smaller Black Holes Illustrated This study relied on the deepest X-ray images ever obtained, the Chandra Deep Fields North and South, plus a key wider-area survey of an area called the "Lockman Hole". The distances to the X-ray sources were determined by optical spectroscopic follow-up at the Keck 10-meter telescope on Mauna Kea in Hawaii, and show the black holes range from less than a billion to 12 billion light years away. Since X-rays can penetrate the gas and dust that block optical and ultraviolet emission, the very long-exposure X-ray images are crucial to find black holes that otherwise would go unnoticed. Black Hole Animation Black Hole Animation Chandra found that many of the black holes smaller than about 100 million Suns are buried under large amounts of dust and gas, which prevents detection of the optical light from the heated material near the black hole. The X-rays are more energetic and are able to burrow through this dust and gas. However, the largest of the black holes show little sign of obscuration by dust or gas. In a form of weight self-control, powerful winds generated by the black hole's feeding frenzy may have cleared out the remaining dust and gas. Other aspects of black hole growth were uncovered. For example, the typical size of the galaxies undergoing supermassive black hole formation reduces with cosmic time. Such "cosmic downsizing" was previously observed for galaxies undergoing star formation. These results connect well with the observations of nearby galaxies, which find that the mass of a supermassive black hole is proportional to the mass of the central region of its host galaxy. The other co-authors on the paper in the February 2005 issue of The Astronomical Journal were Len Cowie, Wei-Hao Wang, and Peter Capak (Institute for Astronomy, Univ. of Hawaii), Yuxuan Yang (GSFC and the Univ. of Maryland, College Park), and Aaron Steffen (Univ. of Wisconsin, Madison). NASA's Marshall Space Flight Center, Huntsville, Ala., manages the Chandra program for NASA's Space Mission Directorate, Washington. Northrop Grumman of Redondo Beach, Calif., formerly TRW, Inc., was the prime development contractor for the observatory. The Smithsonian Astrophysical Observatory controls science and flight operations from the Chandra X-ray Center in Cambridge, Mass. Additional information and images are available at: http://chandra.harvard.edu and http://chandra.nasa.gov
Bioavailability of catechins from tea: the effect of milk.
van het Hof, K H; Kivits, G A; Weststrate, J A; Tijburg, L B
1998-05-01
To assess the blood concentration of catechins following green or black tea ingestion and the effect of addition of milk to black tea. Twelve volunteers received a single dose of green tea, black tea and black tea with milk in a randomized cross-over design with one-week intervals. Blood samples were drawn before and up to eight hours after tea consumption. The study was performed at the Unilever Research Vlaardingen in The Netherlands. Twelve healthy adult volunteers (7 females, 5 males) participated in the study. They were recruited among employees of Unilever Research Vlaardingen. Green tea, black tea and black tea with semi-skimmed milk (3 g tea solids each). Consumption of green tea (0.9 g total catechins) or black tea (0.3 g total catechins) resulted in a rapid increase of catechin levels in blood with an average maximum change from baseline (CVM) of 0.46 micromol/l (13%) after ingestion of green tea and 0.10 micromol/l (13%) in case of black tea. These maximum changes were reached after (mean (s.e.m.)) t=2.3 h (0.2) and t=2.2 h (0.2) for green and black tea respectively. Blood levels rapidly declined with an elimination rate (mean (CVM)) of t1/2=4.8 h (5%) for green tea and t1/2=6.9 h (8%) for black tea. Addition of milk to black tea (100 ml in 600 ml) did not significantly affect the blood catechin levels (areas under the curves (mean (CVM) of 0.53 h. micromol/l (11%) vs 0.60 h. micromol/l (9%) for black tea and black tea with milk respectively. Catechins from green tea and black tea are rapidly absorbed and milk does not impair the bioavailability of tea catechins.
NASA Astrophysics Data System (ADS)
Dehghani, M.
2018-02-01
Making use of the suitable transformation relations, the action of three-dimensional Einstein-Maxwell-dilaton gravity theory has been obtained from that of scalar-tensor modified gravity theory coupled to the Maxwell's electrodynamics as the matter field. Two new classes of the static three-dimensional charged dilatonic black holes, as the exact solutions to the coupled scalar, electromagnetic and gravitational field equations, have been obtained in the Einstein frame. Also, it has been found that the scalar potential can be written in the form of a generalized Liouville-type potential. The conserved black hole charge and masses as well as the black entropy, temperature, and electric potential have been calculated from the geometrical and thermodynamical approaches, separately. Through comparison of the results arisen from these two alternative approaches, the validity of the thermodynamical first law has been proved for both of the new black hole solutions in the Einstein frame. Making use of the canonical ensemble method, a black hole stability or phase transition analysis has been performed. Regarding the black hole heat capacity, with the black hole charge as a constant, the points of type-1 and type-2 phase transitions have been determined. Also, the ranges of the black hole horizon radius at which the Einstein black holes are thermally stable have been obtained for both of the new black hole solutions. Then making use of the inverse transformation relations, two new classes of the string black hole solutions have been obtained from their Einstein counterpart. The thermodynamics and thermal stability of the new string black hole solutions have been investigated. It has been found that thermodynamic properties of the new charged black holes are identical in the Einstein and Jordan frames.
Skyrmion black hole hair: Conservation of baryon number by black holes and observable manifestations
NASA Astrophysics Data System (ADS)
Dvali, Gia; Gußmann, Alexander
2016-12-01
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.
Algebraically special resonances of the Kerr-black-hole-mirror bomb
NASA Astrophysics Data System (ADS)
Hod, Shahar
2013-12-01
A corotating bosonic field interacting with a spinning Kerr black hole can extract rotational energy and angular momentum from the hole. This intriguing phenomenon is known as superradiant scattering. As pointed out by Press and Teukolsky, the black-hole-field system can be made unstable (explosive) by placing a reflecting mirror around the black hole, which prevents the extracted energy from escaping to infinity. This composed black-hole-mirror-field bomb has been studied extensively by many researchers. It is worth noting, however, that most former studies of the black-hole bomb phenomenon have focused on the specific case of confined scalar (spin-0) fields. In the present study we explore the physical properties of the higher-spin (electromagnetic and gravitational) black-hole bombs. It is shown that this composed system is amenable to an analytic treatment in the physically interesting regime of rapidly rotating black holes. In particular, we prove that the composed black-hole-mirror-field bomb is characterized by the unstable resonance frequency ω=mΩH+is·2πTBH (here s and m are, respectively, the spin parameter and the azimuthal harmonic index of the field, and ΩH and TBH are, respectively, the angular-velocity and the temperature of the rapidly spinning black hole). Our results provide evidence that the higher-spin (electromagnetic and gravitational) black-hole-mirror bombs are much more explosive than the extensively studied scalar black-hole-mirror bomb. In particular, it is shown here that the instability growth rates that characterize the higher-spin black-hole bombs are 2 orders of magnitude larger than the instability growth rate of the scalar black-hole bomb.
Sexual Stereotypes Ascribed to Black Men Who Have Sex with Men: An Intersectional Analysis.
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.
NASA Astrophysics Data System (ADS)
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.
Kurt W. Gottschalk
1987-01-01
Northern red oak, black oak, black cherry, and red maple seedlings were grown under light treatments ranging from 8 to 94% of full sunlight for 2 years. Growth was least at the lowest light level and total dry weight increased with increasing light. Total dry-weight rankings (largest to smallest) at all light levels were black cherry, northern red oak, black oak, and...
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.
Barry, Adam E.; Jackson, Zachary; Watkins, Daphne C.; Goodwill, Janelle R.; Hunte, Haslyn E.R.
2016-01-01
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. PMID:27807223
Howard, George; Moy, Claudia S.; Howard, Virginia J.; McClure, Leslie A.; Kleindorfer, Dawn O.; Kissela, Brett M.; Judd, Suzanne E.; Unverzagt, Fredrick W.; Soliman, Elsayed Z.; Safford, Monika M.; Cushman, Mary; Flaherty, Matthew L.; Wadley, Virginia G.
2016-01-01
Background and Purpose At age 45, Blacks have a stroke mortality approximately 3-times greater than their White counterparts, with a declining disparity at older ages. We assess whether this Black-White disparity in stroke mortality is attributable to a Black-White disparity in stroke incidence versus a disparity in case-fatality. Methods We first assess if Black-White differences in stroke mortality within 29,681 participants in the REasons for Geographic And Racial Differences in Stroke (REGARDS) cohort reflect national Black-White differences in stroke mortality, and then assess the degree to which Black-White differences in stroke incidence or 30-day case-fatality after stroke contribute to the disparities in stroke mortality. Results The pattern of stroke mortality within the study mirrors the national pattern, with the Black-to-White hazard ratio of approximately 4.0 at age 45 decreasing to approximately 1.0 at age 85. The pattern of Black-to-White disparities in stroke incidence shows a similar pattern, but no evidence of a corresponding disparity in stroke case-fatality. Discussion These findings show that the Black-White differences in stroke mortality are largely driven by differences in stroke incidence, with case fatality playing at most a minor role. Therefore to reduce the Black-White disparity in stroke mortality, interventions need to focus on prevention of stroke in Blacks. PMID:27256672
Performance of Black Grandmothers: Perceptions of Three Generations of Females
ERIC Educational Resources Information Center
Strom, Robert D.; Heeder, Steven D.; Strom, Paris S.
2005-01-01
The purposes of this study were to (a) identify perceptions of 3 generations about the influence of black grandmothers; (b) describe contributions of black grandmothers and detect obstacles that limit their success; and (c) recommend curricula for programs to enhance success of black grandmothers. The 253 subjects were black grandmothers (n=76),…
Toward Equity for Blacks in Higher Education.
ERIC Educational Resources Information Center
Lyons, Charles A.
The present condition of the United States regarding the education of black college-age youth and the status of historically black colleges is discussed in this paper. Background information on the role of black colleges and an elaboration of present-day problems facing black colleges are presented. The declining enrollment, drop-out rate, counter…
Uneven Stories: Successful Black Collegians at a Black and a White Campus.
ERIC Educational Resources Information Center
Fries-Britt, Sharon L.; Turner, Bridget
2002-01-01
Extensive interviews with academically successful Black students attending a traditionally White and a historically Black institution produced two themes. The first concerns differences in support and campus involvement, and the second reveals how the energy of Black students is either cultivated by their connections with peers and faculty or…
Black Films in Search of a Home.
ERIC Educational Resources Information Center
Taylor, Clyde
1983-01-01
Black filmmakers have produced many films that successfully showcase African-American culture, yet this work is rarely exposed to its intended audience. The Black bourgeoisie, because of their money and social status, must play a role in supporting Black filmmaking and fostering the perception of Black film as part of American popular culture. (GC)
50 CFR 648.146 - Black sea bass recreational fishing season.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 50 Wildlife and Fisheries 12 2012-10-01 2012-10-01 false Black sea bass recreational fishing... Management Measures for the Black Sea Bass Fishery § 648.146 Black sea bass recreational fishing season... possession limit specified in § 648.145(a), may possess black sea bass from January 1 through February 28...
50 CFR 648.143 - Black sea bass Accountability Measures.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Black sea bass Accountability Measures... Management Measures for the Black Sea Bass Fishery § 648.143 Black sea bass Accountability Measures. (a... based on dealer reports, state data, and other available information. All black sea bass landed for sale...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-09-27
.... 100120036-0360-02] RIN 0648-XT99 Fisheries of the Northeastern United States; Black Sea Bass Fishery; 2010 Black Sea Bass Specifications; Emergency Rule Extension; Correction AGENCY: National Marine Fisheries... emergency action to increase the 2010 black sea bass specifications. The preamble text of that rule...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-07-07
...--XT99 [Docket No. 100120036-0038-01] Fisheries of the Northeastern United States; Black Sea Bass Fishery; 2010 Black Sea Bass Specifications; Emergency Rule Extension AGENCY: National Marine Fisheries Service...; emergency action extension. SUMMARY: NMFS is extending the emergency action to increase the 2010 black sea...
50 CFR 648.143 - Black sea bass Accountability Measures.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Black sea bass Accountability Measures... Management Measures for the Black Sea Bass Fishery § 648.143 Black sea bass Accountability Measures. (a... based on dealer reports, state data, and other available information. All black sea bass landed for sale...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-08-30
... Black Sea Bass Fisheries; 2011 Summer Flounder, Scup, and Black Sea Bass Specifications; Correction... Federal Register the final rule to implement the 2011 summer flounder, scup, and black sea bass....100. Need for Correction The final rule implementing 2011 summer flounder, scup, and black sea bass...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-04-23
... Black Sea Bass Fisheries; Final 2012 Summer Flounder, Scup, and Black Sea Bass Specifications AGENCY... management measures, for the 2012 summer flounder, scup, and black sea bass fisheries. The specifications are... specifications for the summer flounder, scup, and black sea bass fisheries, including commercial quotas...
50 CFR 648.144 - Black sea bass gear restrictions.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 50 Wildlife and Fisheries 12 2012-10-01 2012-10-01 false Black sea bass gear restrictions. 648.144... Measures for the Black Sea Bass Fishery § 648.144 Black sea bass gear restrictions. (a) Trawl gear restrictions—(1) General. (i) Otter trawlers whose owners are issued a black sea bass moratorium permit and...
50 CFR 648.143 - Black sea bass Accountability Measures.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 50 Wildlife and Fisheries 12 2012-10-01 2012-10-01 false Black sea bass Accountability Measures... Management Measures for the Black Sea Bass Fishery § 648.143 Black sea bass Accountability Measures. (a... based on dealer reports, state data, and other available information. All black sea bass landed for sale...
50 CFR 648.144 - Black sea bass gear restrictions.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Black sea bass gear restrictions. 648.144... Measures for the Black Sea Bass Fishery § 648.144 Black sea bass gear restrictions. (a) Trawl gear restrictions—(1) General. (i) Otter trawlers whose owners are issued a black sea bass moratorium permit and...
50 CFR 648.144 - Black sea bass gear restrictions.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Black sea bass gear restrictions. 648.144... Measures for the Black Sea Bass Fishery § 648.144 Black sea bass gear restrictions. (a) Trawl gear restrictions—(1) General. (i) Otter trawlers whose owners are issued a black sea bass moratorium permit and...
Federal Register 2010, 2011, 2012, 2013, 2014
2012-12-31
... Black Sea Bass Fisheries; 2012 Summer Flounder, Scup, and Black Sea Bass Specifications; Correction... Register the final rule to implement the 2012 summer flounder, scup, and black sea bass specifications... summer flounder, scup, and black sea bass specifications. Regulations for the summer flounder fishery are...
The Thermodynamics of Black Holes.
Wald, Robert M
2001-01-01
We review the present status of black hole thermodynamics. Our review includes discussion of classical black hole thermodynamics, Hawking radiation from black holes, the generalized second law, and the issue of entropy bounds. A brief survey also is given of approaches to the calculation of black hole entropy. We conclude with a discussion of some unresolved open issues.
Black Male/Female Conflict: Internalization of Negative Definitions Transmitted Through Imagery.
ERIC Educational Resources Information Center
Jewell, K. Sue
1983-01-01
Examines negative images of Black men and women in American society and contrasts these with positive images of Whites. Suggests that the attribution of stereotyped, negative characteristics to Blacks has affected Blacks' perceptions of self-worth and has resulted in interpersonal conflict between Black males and females. (Author/MJL)
Higher Education Equity: The Crisis of Appearance Versus Reality--Revisited. Final Report.
ERIC Educational Resources Information Center
National Advisory Committee on Black Higher Education and Black Colleges and Universities (DHEW), Washington, DC.
The work of the National Advisory Committee on Black Higher Education and Black Colleges and Universities during 1977-1982 is discussed, and information and recommendations on black students and black colleges are presented. After describing the committee's background and functions, the following issues concerning equity for black Americans in…
20 CFR 725.1 - Statutory provisions.
Code of Federal Regulations, 2014 CFR
2014-04-01
... Federal Coal Mine Health and Safety Act of 1969, as amended by the Black Lung Benefits Act of 1972, the Federal Mine Safety and Health Amendments Act of 1977, the Black Lung Benefits Reform Act of 1977, the Black Lung Benefits Revenue Act of 1977, the Black Lung Benefits Amendments of 1981, the Black Lung...
30 CFR 57.6901 - Black powder.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Black powder. 57.6901 Section 57.6901 Mineral...-Surface and Underground § 57.6901 Black powder. (a) Black powder shall be used for blasting only when a... dimension stone. (b) Containers of black powder shall be— (1) Nonsparking; (2) Kept in a totally enclosed...
30 CFR 56.6901 - Black powder.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Black powder. 56.6901 Section 56.6901 Mineral....6901 Black powder. (a) Black powder shall be used for blasting only when a desired result cannot be...) Containers of black powder shall be— (1) Nonsparking; (2) Kept in a totally enclosed cargo space while being...
30 CFR 56.6901 - Black powder.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Black powder. 56.6901 Section 56.6901 Mineral....6901 Black powder. (a) Black powder shall be used for blasting only when a desired result cannot be...) Containers of black powder shall be— (1) Nonsparking; (2) Kept in a totally enclosed cargo space while being...
30 CFR 57.6901 - Black powder.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Black powder. 57.6901 Section 57.6901 Mineral...-Surface and Underground § 57.6901 Black powder. (a) Black powder shall be used for blasting only when a... dimension stone. (b) Containers of black powder shall be— (1) Nonsparking; (2) Kept in a totally enclosed...
ERIC Educational Resources Information Center
Lederer, Richard
1969-01-01
The nature of black literature raises questions about a black aesthetic and the universality of black expression. Central in the writings of Richard Wright and Ralph Ellison are the black man's confusion of identity, stemming from his invisibility in a white America, and the crimes of ignorance and blindness perpetrated on him by whites and by…
Is It because I'm Black? A Black Female Research Experience
ERIC Educational Resources Information Center
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…
Reflections on the Black Woman's Role in the Community of Slaves.
ERIC Educational Resources Information Center
Davis, Angela Y.
1981-01-01
Reprint of a 1971 article that criticizes the notion of Black matriarchy as implying that Black women actively assented to slavery. Discusses Black resistance to slavery, especially among women, and stresses the importance of recognizing such resistance if current popular sociological views on Black women are to be revised. (GC)
The Black Community: Diversity and Unity.
ERIC Educational Resources Information Center
Blackwell, James E.
The black community is defined in this book as a diversified set of interrelated structures and aggregates of people who are held together by the forces of racism. The need for theoretical perspectives for understanding black-white relations and for analyzing the nature of the black community is explained. The black family, patterns of family…
Black Elite: The New Market for Highly Educated Black Americans.
ERIC Educational Resources Information Center
Freeman, Richard B.
This examination of the collapse in traditional discriminatory patterns in the market for highly qualified black Americans documents the World War II gain of college trained and related high level black workers, investigates the response of black college students and qualified personnel to the new market setting, and explores the factors that…
Finding the People's Ideology; Black Theatre at Brown University.
ERIC Educational Resources Information Center
Jones, Rhett S.
The author states that the black revolution went awry because black intellectuals failed to develop what has often been called a black political psychology, that is, the realization of a link between identity and polity, between black self-perspective and political actions; and that the individualistic emphasis of American life is causing upwardly…
A Group Counseling Model for Developing Manhood among Black Male Adolescents.
ERIC Educational Resources Information Center
Lee, Courtland
1991-01-01
A dialogue is presented, which highlights the meaning of success as a Black man. C. Lee's Black Manhood Training Model is discussed, which was developed as a group counseling experience in a school setting for 13- to 17-year-old Black boys to address the challenges of Black male development. (SLD)
The Black Female Experience in America: A Learning/Teacher Guide.
ERIC Educational Resources Information Center
Allman, Joanna; And Others
This book provides a guide for teaching and learning about the experiences of Black females in America, and particularly about psychosocial issues in Black female development. The guide is divided into topic units. "Black Women in History" contains lessons of Black women in slavery, in the twentieth century, and historical and contemporary role…
The Black Man in American Society.
ERIC Educational Resources Information Center
Framingham Public Schools, MA.
GRADE OR AGES: Junior high school. SUBJECT MATTER: The black man in American society. ORGANIZATION AND PHYSICAL APPEARANCE: There are four major parts each with an overview. The four parts concern a) the African heritage of the black man, b) the American exploitation of the black man, c) the black man's contribution to American society, d) the…
30 CFR 57.6901 - Black powder.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Black powder. 57.6901 Section 57.6901 Mineral...-Surface and Underground § 57.6901 Black powder. (a) Black powder shall be used for blasting only when a... dimension stone. (b) Containers of black powder shall be— (1) Nonsparking; (2) Kept in a totally enclosed...
30 CFR 57.6901 - Black powder.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Black powder. 57.6901 Section 57.6901 Mineral...-Surface and Underground § 57.6901 Black powder. (a) Black powder shall be used for blasting only when a... dimension stone. (b) Containers of black powder shall be— (1) Nonsparking; (2) Kept in a totally enclosed...
30 CFR 56.6901 - Black powder.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Black powder. 56.6901 Section 56.6901 Mineral....6901 Black powder. (a) Black powder shall be used for blasting only when a desired result cannot be...) Containers of black powder shall be— (1) Nonsparking; (2) Kept in a totally enclosed cargo space while being...
30 CFR 57.6901 - Black powder.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Black powder. 57.6901 Section 57.6901 Mineral...-Surface and Underground § 57.6901 Black powder. (a) Black powder shall be used for blasting only when a... dimension stone. (b) Containers of black powder shall be— (1) Nonsparking; (2) Kept in a totally enclosed...
30 CFR 56.6901 - Black powder.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Black powder. 56.6901 Section 56.6901 Mineral....6901 Black powder. (a) Black powder shall be used for blasting only when a desired result cannot be...) Containers of black powder shall be— (1) Nonsparking; (2) Kept in a totally enclosed cargo space while being...
30 CFR 56.6901 - Black powder.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Black powder. 56.6901 Section 56.6901 Mineral....6901 Black powder. (a) Black powder shall be used for blasting only when a desired result cannot be...) Containers of black powder shall be— (1) Nonsparking; (2) Kept in a totally enclosed cargo space while being...
Communication Apprehension among Black Students on Predominantly White Campuses.
ERIC Educational Resources Information Center
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…
Problems of Dual-Career Black Couples: Identification and Implications for Family Interventions.
ERIC Educational Resources Information Center
Thomas, Veronica G.
1990-01-01
Examined problems of 41 dual-career Black couples. Findings indicated that dual-career Black couples experienced a number of problems related to their lifestyle. Found unique problems perceived by dual-career Black families. In addition to problems experienced by White dual-career couples, Blacks also faced racial discrimination, social isolation,…
ERIC Educational Resources Information Center
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…
Who's Afraid of the Big Black Man?
ERIC Educational Resources Information Center
Johnson, Jason Kyle
2018-01-01
This article examines the experiences of big Black men in both their personal and professional lives. Black men are often perceived as being aggressive, violent, and physically larger than their White counterparts. The negative perceptions of Black men, particularly big Black men, often leads to negative encounters with police, educators, and…
Exploring Sense of Belonging among Black International Students at an HBCU
ERIC Educational Resources Information Center
Mwangi, Chrystal A. George
2016-01-01
This study elucidates the experiences of HBCU (historically Black colleges and universities) students who are racially Black, but differ in nativity and nationality from their Black American peers. The purpose is to examine Black HBCU international students' sense of belonging on campus. This study engages qualitative individual interviews with…
Graduating Black Males: A Generic Qualitative Study
ERIC Educational Resources Information Center
Bell, Edward E.
2014-01-01
Black males face a difficult educational battle. Across America, graduation statistics for Black males are sobering. The purpose of this study was to explore why Black males drop out of school and to examine the current employment status of the study participants. The research took place in rural North Carolina. Fifteen Black American male high…
Black Mathematics Educators: Researching toward Racial Emancipation of Black Students
ERIC Educational Resources Information Center
Ridgeway, Monica L.; McGee, Ebony O.
2018-01-01
This article focuses on the scholarship of Black mathematics education researchers whose work focuses on Black students in P-20 mathematics spaces. We conducted a metasynthesis literature review of empirical studies by Black mathematics education researchers. The authors utilized critical theories of race and racism to aid in the synthesis of the…
Resisting the Status Quo: The Narratives of Black Homeschoolers in Metro-Atlanta and Metro-DC
ERIC Educational Resources Information Center
Fields-Smith, Cheryl; Kisura, Monica Wells
2013-01-01
Trends suggest that homeschooling continues to increase among black families. Yet, research on contemporary Black homeschooling remains scarce. Given black educational history, the phenomena of Black families choosing homeschooling over public and private schools in the post-Desegregation era is worthy of investigation. Further, documenting the…
ERIC Educational Resources Information Center
Gasman, Marybeth; Nguyen, Thai-Huy; Commodore, Felecia
2017-01-01
To understand the context of urban Historically Black Colleges and Universities (HBCUs) and their role in educating Black males, we conducted a literature review examining the academic contributions of these institutions to Black males. To bolster the literature, we examined Integrated Postsecondary Education Data System data, determining a set of…
School Composition and the Black-White Achievement Gap. NCES 2015-018
ERIC Educational Resources Information Center
Bohrnstedt, G.; Kitmitto, S.; Ogut, B.; Sherman, D.; Chan, D.
2015-01-01
School Composition and the Black-White Achievement Gap explores public schools' demographic composition, in particular, the proportion of Black students enrolled in schools (also referred to "Black student density" in schools) and its relation to the Black-White achievement gap. This NCES study, the first of its kind, used the 2011 NAEP…
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. PMID:11553801
Brügmann, B; Ghez, A M; Greiner, J
2001-09-11
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.
Crisis of Black Athletes on the Eve of the 21st Century.
ERIC Educational Resources Information Center
Edwards, Harry
2000-01-01
Asserts that the dynamics of black youth sports involvement and the blind faith of black youths and families in sports as a vehicle for self-realization and socioeconomic advancement generate complex problems for black society. Black families often push their children toward sports careers, neglecting personal and cultural development. Discusses…
The Core Journal Concept in Black Studies
ERIC Educational Resources Information Center
Weissinger, Thomas
2010-01-01
Black Studies scholars have shown interest in the core journal concept. Indeed, the idea of core journals for the study of the Black experience has changed several times since 1940. While Black Studies scholars are citing Black Studies journals with frequency, they also cite traditional disciplinary journals a great deal of the time. However,…
Black and White College Women's Perceptions of Sexual Harassment.
ERIC Educational Resources Information Center
Shelton, J. Nicole; Chavous, Tabbye M.
1999-01-01
Examined how racial factors influence college women's perceptions of sexual harassment with samples of 46 black and 89 white women. Data suggest that sexual harassment between black women and black men is trivialized compared to sexual behavior between black women and white men. Discusses implications for the study of sexual harassment. (SLD)
Black Women in Academe. Issues and Strategies.
ERIC Educational Resources Information Center
Moses, Yolanda T.
The climate for black women students, faculty members, and administrators in both predominantly white as well as historically black colleges and universities is explored, focusing on the subtle and not so subtle ways that race and gender stereotypes can combine to create double obstacles for black women. Black women students, faculty members, and…
Black Views of American Women: The View From Black Newspapers, 1865-1900.
ERIC Educational Resources Information Center
Beatty, Bess
Although black journalists from 1865 to 1900 were more sensitive to stereotyping and discrimination than their white counterparts, the black papers approached women idealistically, rather than through the realistic situation in which black women existed or through their own awareness of the fact of oppression. The images and proscriptions of women…
ERIC Educational Resources Information Center
Alexander, Benjamin H.
If the black family is to survive, blacks must go into the community, seek out their poor, teach them, minister to them, and Work with them to solve their problems. Black youth, in particular, need support and encouragement. The most successful black children come from two-parent homes. Hence the percentage of black families--35%--headed by a…
Hairy black holes and the endpoint of AdS4 charged superradiance
NASA Astrophysics Data System (ADS)
Dias, Óscar J. C.; Masachs, Ramon
2017-02-01
We construct hairy black hole solutions that merge with the anti-de Sitter (AdS4) Reissner-Nordström black hole at the onset of superradiance. These hairy black holes have, for a given mass and charge, higher entropy than the corresponding AdS4-Reissner-Nordström black hole. Therefore, they are natural candidates for the endpoint of the charged superradiant instability. On the other hand, hairy black holes never dominate the canonical and grand-canonical ensembles. The zero-horizon radius of the hairy black holes is a soliton (i.e. a boson star under a gauge transformation). We construct our solutions perturbatively, for small mass and charge, so that the properties of hairy black holes can be used to testify and compare with the endpoint of initial value simulations. We further discuss the near-horizon scalar condensation instability which is also present in global AdS4-Reissner-Nordström black holes. We highlight the different nature of the near-horizon and superradiant instabilities and that hairy black holes ultimately exist because of the non-linear instability of AdS.
George, Clemon; Adam, Barry A; Read, Stanley E; Husbands, Winston C; Remis, Robert S; Makoroka, Lydia; Rourke, Sean B
2012-01-01
In Canada, there is a paucity of research aimed at understanding Black gay men and the antecedents to risk factors for HIV. This study is an attempt to move beyond risk factor analysis and explore the role of sexual and ethnic communities in the lives of these men. The study utilized a community-based research and critical race theory approach. Semi-structured interviews were conducted with eight key informants to augment our understanding of Black gay men and to facilitate recruitment of participants. In-depth interviews were done with 24 Black gay men. Our data showed that the construction of community for Black gay men is challenged by their social and cultural environment. However, these men use their resilience to navigate gay social networks. Black gay men expressed a sense of abjuration from both gay and Black communities because of homophobia and racism. It is essential for health and social programmers to understand how Black gay men interact with Black and gay communities and the complexities of their interactions in creating outreach educational, preventive and support services.
Ethnicity, Nativity and the Health of American Blacks
Griffith, Derek M.; Johnson, Jonetta; Zhang, Rong; Neighbors, Harold W.; Jackson, James S.
2012-01-01
Few national studies have empirically examined ethnic differences in health within the American Black population. We utilized logistic regression to examine the relationships among ethnicity, nativity, depressive symptoms, and physical health in the two largest ethnic groups of American Blacks, African Americans and Caribbean Blacks. The data were from the National Survey of American Life, an in-person national household survey representative of the non-institutionalized U.S. Black population. We found that African Americans, U.S.-born Caribbean Blacks, and Caribbean-born Blacks had significantly different self-ratings of their health and self-reports of being diagnosed with a chronic physical health condition. Whether assessed by self-rated health or the presence of at least one physician diagnosed chronic health condition, Caribbean-born Blacks had the best health outcomes and U.S.-born Caribbean Blacks had the worst. This finding remained significant even after considering self-reported depressive symptoms. This study highlights the importance of considering ethnic diversity, nativity and immigration as independent sources of variation in health status within the American Black population. PMID:21317512
Relation between vegetarian/nonvegetarian diets and blood pressure in black and white adults.
Melby, C L; Goldflies, D G; Hyner, G C; Lyle, R M
1989-01-01
We examined the possible interaction of race and diet on blood pressure (BP) in volunteer Black Seventh Day Adventists compared to volunteer White church members. Height, weight, waist and hip circumference, and resting seated BP were recorded in Black vegetarians (n = 55; age: 54.7 +/- 16.9 yrs), Black nonvegetarians (n = 59; 56.1 +/- 14.1 yrs), White vegetarians (n = 164; 52.2 +/- 16.7 yrs), and White nonvegetarians (n = 100; 52.6 +/- 15.6 yrs) attending a regional conference. Forty-four percent of the Black nonvegetarians were medicated hypertensives, compared to only 18 percent of the Black vegetarians, 7 percent of the White vegetarians, and 22 percent of the White nonvegetarians. Black vegetarians exhibited lower age and sex-adjusted systolic BP (means = 122.9/74.4 mm Hg) than Black nonvegetarians (means = 132.2/75.9 mm Hg). After further adjusting BP for body mass index and waist/hip ratio, the systolic BP among Black vegetarians remained lower (122.8) than Black nonvegetarians (129.7) but higher than that of the Whites who showed no diet-related BP differences. PMID:2764208
Supermassive black holes do not correlate with dark matter haloes of galaxies.
Kormendy, John; Bender, Ralf
2011-01-20
Supermassive black holes have been detected in all galaxies that contain bulge components when the galaxies observed were close enough that the searches were feasible. Together with the observation that bigger black holes live in bigger bulges, this has led to the belief that black-hole growth and bulge formation regulate each other. That is, black holes and bulges coevolve. Therefore, reports of a similar correlation between black holes and the dark matter haloes in which visible galaxies are embedded have profound implications. Dark matter is likely to be non-baryonic, so these reports suggest that unknown, exotic physics controls black-hole growth. Here we show, in part on the basis of recent measurements of bulgeless galaxies, that there is almost no correlation between dark matter and parameters that measure black holes unless the galaxy also contains a bulge. We conclude that black holes do not correlate directly with dark matter. They do not correlate with galaxy disks, either. Therefore, black holes coevolve only with bulges. This simplifies the puzzle of their coevolution by focusing attention on purely baryonic processes in the galaxy mergers that make bulges.
... 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 ...
Newsome, Frederick
1979-01-01
During several millenia, blacks in ancient Egypt made numerous contributions to medicine and were acknowledged as the inventors of the art of medicine. They produced the earliest physicians, medical knowledge, and medical literature. They contributed to the development of medicine in ancient Greece. Ancient writers, including Herodotus, Isocrates, and Diodorus, affirm this. Modern presentations of ancient medicine, however, deprive blacks of the knowledge of their early contributions to medicine by ignoring or subtly misrepresenting the black identity of the ancient Egyptians. Blacks are currently under-represented in US medical schools. It is proposed that the recognition of the contributions of blacks to the early history of Western medicine would inspire black students to study medicine. PMID:423296
PREJUDICE & POLICY Racial Discrimination in the Union Army Disability Pension System, 1865-1906
2010-01-01
The Union Army disability pension was an early experiment in colorblind social policy. However, it shortchanged Blacks in 2 ways. First, the law was unable to account for the challenges Blacks faced in proving their eligibility because of the legacy of slavery and discrimination against Black troops during the Civil War. Second, the increasing leniency accorded White soldiers by the Pension Bureau was not extended in the same measure to Blacks. Active discrimination against Blacks resulted in part from local discretion, evidenced by the significantly lower approval rates for both White and Black veterans in the South. Furthermore, when Whites and Blacks claimed disabilities that were easily verifiable, outcomes were similar, but when verification required a degree of trust, Blacks fared considerably worse than Whites. PMID:20147675
The Longue Durée of Black Lives Matter.
Nelson, Alondra
2016-10-01
Black Lives Matter was first articulated just a few years ago, but it has been the leitmotif of antiracist struggles for generations. The Movement for Black Lives extends the work of previous movements that challenged forms of oppression that act on Black bodies with impunity. It should be understood in the context of Ida B. Wells' anti-lynching campaign, Fannie Lou Hamer's reproductive justice demands, and the Black Panther Party's health activism. The 50th anniversary of the Black Panther Party is an occasion to recall that its work confronted the callous neglect and the corporeal surveillance and abuse of poor Black communities. Similar demands have been the centrifugal force of social movements that for centuries have refused to have Black lives cast beyond the human boundary.
The Longue Durée of Black Lives Matter
2016-01-01
Black Lives Matter was first articulated just a few years ago, but it has been the leitmotif of antiracist struggles for generations. The Movement for Black Lives extends the work of previous movements that challenged forms of oppression that act on Black bodies with impunity. It should be understood in the context of Ida B. Wells’ anti-lynching campaign, Fannie Lou Hamer’s reproductive justice demands, and the Black Panther Party’s health activism. The 50th anniversary of the Black Panther Party is an occasion to recall that its work confronted the callous neglect and the corporeal surveillance and abuse of poor Black communities. Similar demands have been the centrifugal force of social movements that for centuries have refused to have Black lives cast beyond the human boundary. PMID:27626337
Landrine, Hope; Klonoff, Elizabeth A; Fernandez, Senaida; Hickman, Norval; Kashima, Kennon; Parekh, Bina; Thomas, KaMala; Brouillard, Catherine R; Zolezzi, Michelle; Jensen, Jennifer A; Weslowski, Zorahna
2005-01-01
To examine the number, type (menthol vs non-menthol), brand (Black, White, Women's, Other), and size of cigarette ads in Black, Latino, and White magazines. Analysis of digital photographs of 274 cigarette ads appearing in Ebony (Black), People (White), and People in Spanish (Latino) for the 4.5-year period of January 1998 to August 2002. Black magazines were 9.8 times and Latino magazines 2.6 times more likely than White magazines to contain ads for menthol cigarettes. Black and Latino magazines also contained significantly more ads for brands (Virginia Slims) that target women. The tobacco industry continues to target Blacks with menthol cigarette ads, appears now to be targeting Latinos similarly, and targets Black and Latino women with additional, tailored cigarette ads.
Exposure of black youths to cigarette advertising in magazines
King, C.; Siegel, M.; Pucci, L.
2000-01-01
OBJECTIVE—To estimate the potential exposure of black adolescents to brand specific advertising in magazines. DESIGN—A probit regression analysis was conducted of pooled 1990 and 1994 data on brand specific advertising in 36 popular US magazines to examine the relationship between the presence or absence of advertising in each magazine for each of 12 cigarette brands, and the proportion of each magazine's youth (ages 12-17 years) readers who were black. MAIN OUTCOME MEASURES—The presence or absence of advertising in each magazine in 1990 and 1994, for each of 12 cigarette brands. RESULTS—After controlling for total magazine readership and the percentage of young adult, Hispanic, and female readers, black youth cigarette brands (those whose market share among black youths exceeded their overall market share) were more likely than other brands to advertise in magazines with a higher percentage of black youth readers. Holding all other variables constant at their sample means, the probability of a non-black youth brand advertising in a magazine decreased over the observed range of percentage black youth readership from 0.65 (95% confidence interval (CI) 0.55 to 0.75) for magazines with 5% black youth readers to 0.33 (95% CI 0.00 to 0.69) for magazines with 91% black youth readers. In contrast, the probability of a black youth brand advertising in a magazine increased from 0.40 (95% CI 0.17 to 0.62) at 5% black youth readership to 1.00 (95% CI 0.97 to 1.00) at 91% black youth readership. CONCLUSIONS—Black youths are more likely than white youths to be exposed to magazine advertising by cigarette brands popular among black adolescents. Keywords: advertising; magazines; youths PMID:10691759
Black holes in binary stellar systems and galactic nuclei
NASA Astrophysics Data System (ADS)
Cherepashchuk, A. M.
2014-04-01
In the last 40 years, following pioneering papers by Ya B Zeldovich and E E Salpeter, in which a powerful energy release from nonspherical accretion of matter onto a black hole (BH) was predicted, many observational studies of black holes in the Universe have been carried out. To date, the masses of several dozen stellar-mass black holes (M_BH = (4{-}20) M_\\odot) in X-ray binary systems and of several hundred supermassive black holes (M_BH = (10^{6}{-}10^{10}) M_\\odot) in galactic nuclei have been measured. The estimated radii of these massive and compact objects do not exceed several gravitational radii. For about ten stellar-mass black holes and several dozen supermassive black holes, the values of the dimensionless angular momentum a_* have been estimated, which, in agreement with theoretical predictions, do not exceed the limiting value a_* = 0.998. A new field of astrophysics, so-called black hole demography, which studies the birth and growth of black holes and their evolutionary connection to other objects in the Universe, namely stars, galaxies, etc., is rapidly developing. In addition to supermassive black holes, massive stellar clusters are observed in galactic nuclei, and their evolution is distinct from that of supermassive black holes. The evolutionary relations between supermassive black holes in galactic centers and spheroidal stellar components (bulges) of galaxies, as well as dark-matter galactic haloes are brought out. The launch into Earth's orbit of the space radio interferometer RadioAstron opened up the real possibility of finally proving that numerous discovered massive and highly compact objects with properties very similar to those of black holes make up real black holes in the sense of Albert Einstein's General Relativity. Similar proofs of the existence of black holes in the Universe can be obtained by intercontinental radio interferometry at short wavelengths \\lambda \\lesssim 1 mm (the international program, Event Horizon Telescope).
Sizes of Black Holes Throughout the Universe
NASA Astrophysics Data System (ADS)
Kohler, Susanna
2018-05-01
What is the distribution of sizes of black holes in our universe? Can black holes of any mass exist, or are there gaps in their possible sizes? The shape of this black-hole mass function has been debated for decades and the dawn of gravitational-wave astronomy has only spurred further questions.Mind the GapsThe starting point for the black-hole mass function lies in the initial mass function (IMF) for stellar black holes the beginning size distribution of black holes after they are born from stars. Instead of allowing for the formation of stellar black holes of any mass, theoretical models propose two gaps in the black-hole IMF:An upper mass gap at 50130 solar masses, due to the fact that stellar progenitors of black holes in this mass range are destroyed by pair-instability supernovae.A lower mass gap below 5 solar masses, which is argued to arise naturally from the mechanics of supernova explosions.Missing black-hole (BH) formation channels due to the existence of the lower gap (LG) and the upper gap (UG) in the initial mass function. a) The number of BHs at all scales are lowered because no BH can merge with BHs in the LG to form a larger BH. b) The missing channel responsible for the break at 10 solar masses, resulting from the LG. c) The missing channel responsible for the break at 60 solar masses, due to the interaction between the LG and the UG. [Christian et al. 2018]We can estimate the IMF for black holes by scaling a typical IMF for stars and then adding in these theorized gaps. But is this initial distribution of black-hole masses the same as the distribution that we observe in the universe today?The Influence of MergersBased on recent events, the answer appears to be no! Since the first detections of gravitational waves in September 2015, we now know that black holes can merge to form bigger black holes. An initial distribution of black-hole masses must therefore evolve over time, as mergers cause the depletion of low-mass black holes and an increase in higher-mass black holes.A team of scientists led by Pierre Christian, an Einstein Fellow at Harvard University, has now looked into characterizing this shift. In particular, Christian and collaborators explore how black-hole mergers in the centers of dense star clustersultimately shape the black-hole mass function of the universe.Black Holes TodayChristian and collaborators use analytical models of coagulation mergers of particles to form larger particles to estimate the impact of mergers in star clusters on resulting black-hole sizes. They find that, over an evolution of 10 billion years, mergers can appreciably fill in the upper mass gap of the black-hole IMF.An example of the black-hole mass function that can result from evolving the initial mass function complete with gaps over time. Two breaks appear as a result of the initial gaps: one at 10 (LB) and one at 60 solar masses (UB). [Christian et al. 2018]The lower mass gap, on the other hand, leaves observable signatures in the final black-hole mass function: a break at 10 solar masses (since black holes below this mass cant be created by mergers) and one at 60 solar masses (caused by the interaction of the upper and lower gaps). As we build up black-hole statistics in the future (thanks, gravitational-wave detectors!), searching for these breaks will help us to test our models.Lastly, the authors find that their models can only be consistent with observations if ejection is efficient black holes must be regularly ousted from star clusters through interactions with other bodies or as a result of kicks when they merge. This idea is consistent with many recent studies supporting a large population of free-floating stellar-mass black holes.CitationPierre Christian et al 2018 ApJL 858 L8. doi:10.3847/2041-8213/aabf88
Mass-induced instability of SAdS black hole in Einstein-Ricci cubic gravity
NASA Astrophysics Data System (ADS)
Myung, Yun Soo
2018-05-01
We perform the stability analysis of Schwarzschild-AdS (SAdS) black hole in the Einstein-Ricci cubic gravity. It shows that the Ricci tensor perturbations exhibit unstable modes for small black holes. We call this the mass-induced instability of SAdS black hole because the instability of small black holes arises from the massiveness in the linearized Einstein-Ricci cubic gravity, but not a feature of higher-order derivative theory giving ghost states. Also, we point out that the correlated stability conjecture holds for the SAdS black hole by computing the Wald entropy of SAdS black hole in Einstein-Ricci cubic gravity.
Hawking Tunneling Radiation of Black Holes in de Sitter and ANTI-de Sitter Spacetimes
NASA Astrophysics Data System (ADS)
Jiang, Qing-Quan; Li, Hui-Ling; Yang, Shu-Zheng; Chen, De-You
Applying Parikh-Wilczek's semiclassical quantum tunneling method, we investigate the tunneling radiation characteristics of a torus-like black hole and Kerr-Newman-Kausya de Sitter black hole. Both black holes have the cosmological constant Λ, but a torus-like black hole is in anti-de Sitter spacetime and the other black hole is in de Sitter spacetime. The derived results show that the tunneling rate is related to the change of Bekenstein-Hawking entropy, and the factual radiated spectrum is not precisely thermal, but is consistent with an underlying unitary theory, which gives a might explanation to the paradox of black hole information lost.
Ogden, Jane; Russell, Sheriden
2013-12-01
This qualitative think aloud study explored how Black women (n = 32) processed information from a White or Black fashion magazine. Comments to the 'White' magazine were characterised by rejection, being critical of the media and ambivalence, whereas they responded to the 'Black' magazine with celebration, identification and a search for depth. Transcending these themes was their self-identity of being a Black woman that was brought to the fore either by a sense of exclusion (White magazine) or engagement (Black magazine). Such an identity provides resilience against the media's thin ideals by minimising the processes of social comparison and internalisation.
Black-on-black homicide: Kansas City's response.
Mitchell, M A; Daniels, S
1989-01-01
In many metropolitan areas, homicide continues to be the scourge of black Americans despite increasing awareness of the overrepresentation of blacks among victims and perpetrators. The risk of being a homicide victim among black males is so high that the Department of Health and Human Services has set a priority of reducing the risk to 60 per 100,000 by 1990. The recent escalation in the number of homicides in the United States associated with drugs makes attainment of that goal unlikely. In Kansas City, a black community grassroots organization, the Ad Hoc Group Against Crime, commissioned a multidisciplinary task force to study black-on-black homicide in 1986. The report generated by this task force identified factors placing Kansas Citians at high risk of being homicide victims or perpetrators, including being black, male, unemployed, between the ages 17-29, a high school nongraduate, frequently involved in or around violence, and having prior arrests on weapons charges. One hundred recommendations were made, of which 12 were targeted for immediate implementation. These included increasing public awareness of the incidence of black-on-black homicide, involvement of black men in role model programs for young black males, training in anger control and alternatives to violence for those identified as being at high risk for homicide, and providing a role for ex-offenders in violence prevention. Working with community organizations has inherent strengths and weaknesses for public health workers. However, such a group can successfully impact the affected community in ways which would be difficult for traditional resources. PMID:2511593
Black Carbon Measurement and Modeling in the Arabian Peninsula
NASA Astrophysics Data System (ADS)
Zawad, Faisal Al; Khoder, Mamdouh; Almazroui, Mansour; Alghamdi, Mansour; Lihavainen, Heikki; Hyvarinen, Antti; Henriksson, Svante
2017-04-01
Black carbon is an important atmospheric aerosol as an effective factor in public health, changing the global and regional climate, and reducing visibility. Black carbon absorbs light, warms the atmosphere, and modifies cloud droplets and the amount of precipitation. In spite of this significance, knowledge of black carbon over the Arabian Peninsula is hard to find in literature until recently. The total mass of black carbon and wind direction and speeds were measured continuously at Hada Al-Sham, Saudi Arabia for the year 2013. In addition, a state of the art global aerosol - climate model (ECHAM5-HAM) was used to determine black carbon climatology over the Arabian Peninsula. Simulation of the model was carried out for the years eight years (2004 - 2011). The daily mean values of the concentrations of black carbon had a minimum of 15.0 ng/m3 and a maximum of 6372 ng/m3 with a mean of at 1899 ng/m3. The diurnal pattern of black carbon showed higher values overnight, and steady low values during daytimes caused by sea and land breezes. Seasons of black carbon vary over the Arabian Peninsula, and the longest is in the Northern Region where it lasts from July to October. High concentrations of black carbon at Hada Al-Sham was observed with a mean of 1.9 µm/m3, and seasons of black carbon vary widely across the Arabian Peninsula. Assessment of the effects of black carbon over the Arabian Peninsula on the global radiation balance. Initiating a black carbon monitoring network is highly recommended to assess its impacts on health, environment, and climate.
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.
UH-60M Black Hawk Helicopter (UH-60M Black Hawk)
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
NASA Technical Reports Server (NTRS)
Garica, M.
2001-01-01
In 1995 we proposed to carry out ground-based observations in order to securely identify stellar mass black holes in our galaxy. This type 4 proposal under NASA's UV, Visible, and Gravitational Astrophysics program compliments NASA's space-based research by following up black hole candidates found and studied with space-based observatories, in order to determine if they are indeed black holes. While our primary goal is to securely identify black holes by measuring their masses, a secondary goal is identifying unique visible-range signatures for black holes.
Black youth suicide: literature review with a focus on prevention.
Baker, F. M.
1990-01-01
The national rates of completed suicide in the black population between 1950 and 1981 are presented, including age-adjusted rates. Specific studies of black suicide attempters and completed suicides by blacks in several cities are discussed. Methodological problems with existing studies and national suicide statistics are presented. Proposed theories of black suicide are reviewed. Based on a summary of the characteristics of black suicide attempters reported by the literature, preventive strategies--primary, secondary, and tertiary--are presented. PMID:2204709
Okuda, Mayumi; Oquendo, Maria A.; Lawson, William B.; Wang, Shuai; Thomas, Yonette Felicity; Blanco, Carlos
2013-01-01
Objectives. Previous epidemiological studies have found lower mood, anxiety, and substance use disorder prevalence in Black Americans, in general, compared with White Americans. We estimated the prevalence and persistence of psychiatric disorders in African Americans, Caribbean Blacks, and non-Hispanic Whites. Methods. We drew data from wave 1 (2001–2002) of the National Epidemiological Survey of Alcohol and Related Conditions, a nationally representative sample of US adults, which included 7529 African Americans, 469 Caribbean Blacks, and 24 502 non-Hispanic Whites. Results. Blacks had equal or lower prevalence than Whites of lifetime (adjusted odds ratio [AOR] = 0.6 for African Americans; 0.3 for Caribbean Blacks) and 12-month (AOR = 0.7 for African Americans; 0.4 for Caribbean Blacks) Axis I psychiatric disorders, but higher prevalence of several personality disorders. Among Blacks, Caribbean Blacks had higher prevalence of 12-month psychotic disorders and lower lifetime prevalence of major depressive disorder, alcohol dependence, and drug abuse than African Americans. There were no differences in persistence of disorders between Caribbean Blacks and African Americans. Conclusions. This study yielded new data on prevalence of mental disorders in these groups, which has important implications for clinical work with US Blacks. PMID:23237171
NASA Astrophysics Data System (ADS)
Muryanto, Muryanto; Hanifah, Ummu; Amriani, Feni; Ibadurrahman, Ahmad Faiz; Sari, Ajeng Arum
2017-11-01
High amounts of black liquor are generated from bioethanol production by using oil palm empty fruit bunches. The black liquor is waste from alkaline pretreatment, it contains high amount of an alkaline solution (NaOH). The black liquor wastewater was highly contaminated with organic materials, and quite toxic for aquatic ecosystems if discharged directly into waters. This study aimed to determine ability of Fenton process combined with coagulation to treat black liquor. The addition 5% of polyaluminium chloride (PAC) could decolorized black liquor, degraded lignin, and produced sludge 70.64%, 68.28%, and 2.76 gram, respectively. Decolorization of black liquor was in line with degradation of black liquor because lignin is the main compound in black liquor. SEM images after addition of PAC of 5% indicated fragmentation of structure. Fenton reagent consist of 0.7 M FeSO4+ 3M H2O2 has able to decolorize black liquor, degrade lignin, and produce sludge 51.67% and 25.44%, and 0.44 gram, respectively. It was concluded that black liquor wastewater from bioethanol can be treated by using Fenton process combined with coagulation. However, these methods still need improvement to obtain the higher degradation rate, and coagulation sludge needs further consideration.
Lightbourn, Gordon J; Griesbach, Robert J; Novotny, Janet A; Clevidence, Beverly A; Rao, David D; Stommel, John R
2008-01-01
Shades ranging from violet to black pigmentation in pepper (Capsicum annuum L.) are attributed to anthocyanin accumulation. High-performance liquid chromatography and mass spectrometry analysis of violet and black fruit tissue identified a single anthocyanin that was determined to be delphinidin-3-p-coumaroyl-rutinoside-5-glucoside. Leaf tissue of a black-pigmented foliage genotype contained the same anthocyanin found in fruit but at a considerably higher concentration in comparison to violet and black fruit tissue. Fruit chlorophyll concentration was approximately 14-fold higher in black fruit in comparison to violet fruit that contained relatively little chlorophyll. Beta-carotene, lutein, violaxanthin, and neoxanthin carotenoid concentrations in black fruit were also significantly greater in comparison to violet fruit. High concentrations of delphinidin in combination with chlorophyll and accessory carotenoid pigments produced the characteristic black pigmentation observed in fruits and leaves of selected genotypes. Anthocyanins were accumulated in the outer mesocarp of violet and black fruit and in the palisade and mesophyll cells of black leaves. Consistent with chlorophyll content of respective genotypes, chloroplast density was greater in cells of black fruits. Utilizing Capsicum pigment variants, we determine the biochemical factors responsible for violet versus black-pigmented pepper tissue in the context of described pepper color genes.
Genetic dissection of black grain rice by the development of a near isogenic line.
Maeda, Hiroaki; Yamaguchi, Takuya; Omoteno, Motoyasu; Takarada, Takeshi; Fujita, Kenji; Murata, Kazumasa; Iyama, Yukihide; Kojima, Yoichiro; Morikawa, Makiko; Ozaki, Hidenobu; Mukaino, Naoyuki; Kidani, Yoshinori; Ebitani, Takeshi
2014-06-01
Rice (Oryza sativa L.) can produce black grains as well as white. In black rice, the pericarp of the grain accumulates anthocyanin, which has antioxidant activity and is beneficial to human health. We developed a black rice introgression line in the genetic background of Oryza sativa L. 'Koshihikari', which is a leading variety in Japan. We used Oryza sativa L. 'Hong Xie Nuo' as the donor parent and backcrossed with 'Koshihikari' four times, resulting in a near isogenic line (NIL) for black grains. A whole genome survey of the introgression line using DNA markers suggested that three regions, on chromosomes 1, 3 and 4 are associated with black pigmentation. The locus on chromosome 3 has not been identified previously. A mapping analysis with 546 F2 plants derived from a cross between the black rice NIL and 'Koshihikari' was evaluated. The results indicated that all three loci are essential for black pigmentation. We named these loci Kala1, Kala3 and Kala4. The black rice NIL was evaluated for eating quality and general agronomic traits. The eating quality was greatly superior to that of 'Okunomurasaki', an existing black rice variety. The isogenicity of the black rice NIL to 'Koshihikari' was very high.
Black Hole Boldly Goes Where No Black Hole Has Gone Before
NASA Astrophysics Data System (ADS)
2007-01-01
Astronomers have found a black hole where few thought they could ever exist, inside a globular star cluster. The finding has broad implications for the dynamics of stars clusters and also for the existence of a still-speculative new class of black holes called 'intermediate-mass' black holes. The discovery is reported in the current issue of Nature. Tom Maccarone of the University of Southampton in England leads an international team on the finding, made primarily with the European Space Agency's XMM-Newton satellite. Globular clusters are dense bundles of thousands to millions of old stars, and many scientists have doubted that black holes could survive in such an exclusive environment. Computer simulations show that a newly formed black hole would first sink towards the centre of the cluster but quickly get gravitationally slingshot out entirely when interacting with the cluster's myriad stars. Credit: ESA/Hubble Artist's impression of globular star cluster The new finding provides the first convincing evidence that some black hole might not only survive but grow and flourish in globular clusters. What has astonished astronomers is how quickly the black hole was found. "We were preparing for a long, systematic search of thousands of globular clusters with the hope of finding just one black hole," said Maccarone. "But bingo, we found one as soon as we started the search. It was only the second globular cluster we looked at." The search continues to find more, Maccarone said, yet only one black hole was needed to resolve the decades-old discussion about black holes and globular clusters. Scientists say there are two main classes of black holes. Supermassive black holes containing the mass of millions to billions of suns are found in the core of most galaxies, including our own. A quasar is one kind of supermassive black hole. Stellar-size black holes contain the mass of about ten suns. These are created from the collapsed core of massive stars. Our galaxy likely contains millions of these black holes. Black holes are, by definition, invisible. But the region around them can flare up periodically when the black hole feeds. As gas falls into a black hole, it will heat to high temperatures and radiate brightly, particularly in X-rays. Maccarone's team found one such stellar-mass black hole by chance feeding in a globular cluster in a galaxy named NGC 4472, about fifty million light-years away in the Virgo Cluster. XMM-Newton is extremely sensitive to variable X-ray sources and can efficiently search across large patches of the sky. The team also used NASA's Chandra X-ray Observatory, which has superb angular resolution to pinpoint the X-ray source's location. This allowed them to match up the position of the X-ray source with optical images to prove that the black hole was indeed in a globular cluster. Globular clusters are some of the oldest structures in the universe, containing stars over 12 thousand million years old. Black holes in a cluster would likely have formed many thousand millions of years ago, which is why astronomers have assumed they would have been kicked out a long time ago. Details in the X-ray light detected by XMM-Newton leave little doubt that this is a black hole - the object is too bright, and varies by too much to be anything else. In fact, the source is 'extra bright', - an Ultraluminous X-ray object, or ULX. ULXs are brighter than the 'Eddington limit' for stellar mass black holes, the brightness level at which the outward force from X-rays is expected balance the powerful gravitational forces from the black hole. Thus it is often suggested that the ULXs might be intermediate mass black holes - black holes of thousands of solar masses, heavier than the 10-solar-mass stellar black holes, and lighter than the million to thousand million solar mass black holes in quasars. These black holes might then be the missing links between the black holes formed in the death throes of massive stars and the ones in the centres of galaxies. It is perhaps possible for a stellar-mass black hole to gain enough mass through merging with other stellar-mass black holes or accreting star gas to stay locked in a cluster. About 100 solar masses would do. Once entrenched, the black hole has the opportunity to merge with other black holes or accrete gas from a local neighbourhood rife with star-stuff. In this way, they could grow into IMBHs. "If a black hole is massive enough, there's a good chance it can survive the pressures of living in a globular cluster, since it will be too heavy to be kicked out," said Arunav Kundu of Michigan State University, a co-author on the Nature report. "That's what is intriguing about this discovery. We may be seeing how a black hole can grow considerably, become more entrenched in the cluster, and then grow some more. "On the other hand," continued Kundu, "there are a variety of ways to make ULXs without requiring intermediate mass black holes. In particular, if the light goes out in a different direction than the one from which the gas comes in, it doesn't put any force on the gas. Also, if the light can be 'focused' towards us by reflecting off the gas in the same way that light from a flashlight bulb bounces off the little mirror in the flashlight, making the object appear brighter than it really is." Ongoing work will help to determine whether this object is a stellar-mass black hole showing an unusual manner of sucking in gas, allowing it to be extra bright, or an IMBH. The team, which also includes Steve Zepf from Michigan State University, and Katherine Rhode from Wesleyan University, has data for thousands of other globular clusters, which they are now analyzing in an effort to determine just how common this phenomenon is. Note for editors The findings appear on line in the 4 January issue of the journal Nature, in the article titled: "A black hole in a globular cluster", by Thomas J. Maccarone, Arunav Kundu, Stephen E. Zepf and Katherine L. Rhode.
ERIC Educational Resources Information Center
Mlambo, Yeukai Angela
2017-01-01
Black African women are grossly underrepresented as academic staff in engineering programs at South African universities. The problem is exacerbated at historically White institutions (HWI) where Black women are simply absent as engineering research and teaching staff. The absence of Black African women in the academy occurs despite Black African…
ERIC Educational Resources Information Center
Clay, William L.
This speech by a black congressman from Missouri concerns the context in which general questions about black children must be answered. These questions include: (1) How can service providers, institutions, and government entities implement a vision for the future of black children? and (2) How can organizations that serve black children ensure…
Adaptability of black walnut, black cherry, and Northern red oak to Northern California
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...
ERIC Educational Resources Information Center
Muhammad, Gholnecsar E.; McArthur, Sherell A.
2015-01-01
Identity formation is a critical process shaping the lives of adolescents and can present distinct challenges for Black adolescent girls who are positioned in society to negotiate ideals of self when presented with false and incomplete images representing Black girlhood. Researchers have found distorted images of Black femininity derived from…
A History of Black Professional Football Players from 1900-1946.
ERIC Educational Resources Information Center
Acanfora, Jerry A.
The history of Black professional football is obscure, although it is known that in the early years Black and White athletes played together on basis of ability. Several Black Americans were members of early professional football teams; however, in the late 1920s, they seemed to disappear from team rosters. Each of the eighteen Black professional…
The Delivery of Mental Health Services to Black Children. Final Report.
ERIC Educational Resources Information Center
Gary, Lawrence E.; And Others
This study was designed to start a data base on black mental health practitioners working with black clients. The sample group consisted of 177 (57 men, 120 women) black school counselors and 36 (5 men, 31 women) psychologists in seven predominantly black, urban public schools. The information gathered covered the following areas: (1) demographics…
The Use of Blacks in Magazine and Television Advertising: 1946 to 1986.
ERIC Educational Resources Information Center
Zinkhan, George M.; And Others
1990-01-01
Combines earlier content analysis studies with original data from five magazines in 1986 to examine the use of Blacks in magazine and television advertising. Finds an increase in the Black presence in advertising. Notes that the Black presence in television commercial sometimes approaches the percentage of Blacks in the population. Notes a less…
50 CFR 648.140 - Black sea bass Annual Catch Limit (ACL).
Code of Federal Regulations, 2014 CFR
2014-10-01
... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Black sea bass Annual Catch Limit (ACL... Management Measures for the Black Sea Bass Fishery § 648.140 Black sea bass Annual Catch Limit (ACL). (a) The Black Sea Bass Monitoring Committee shall recommend to the MAFMC separate ACLs for the commercial and...
50 CFR 648.141 - Black sea bass Annual Catch Target (ACT).
Code of Federal Regulations, 2013 CFR
2013-10-01
... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Black sea bass Annual Catch Target (ACT... Management Measures for the Black Sea Bass Fishery § 648.141 Black sea bass Annual Catch Target (ACT). (a) The Black Sea Bass Monitoring Committee shall identify and review the relevant sources of management...
50 CFR 648.147 - Black sea bass minimum fish sizes.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Black sea bass minimum fish sizes. 648... Measures for the Black Sea Bass Fishery § 648.147 Black sea bass minimum fish sizes. (a) Moratorium (commercially) permitted vessels. The minimum size for black sea bass is 11 inches (27.94 cm) total length for...
50 CFR 648.141 - Black sea bass Annual Catch Target (ACT).
Code of Federal Regulations, 2014 CFR
2014-10-01
... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Black sea bass Annual Catch Target (ACT... Management Measures for the Black Sea Bass Fishery § 648.141 Black sea bass Annual Catch Target (ACT). (a) The Black Sea Bass Monitoring Committee shall identify and review the relevant sources of management...
50 CFR 648.147 - Black sea bass minimum fish sizes.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 50 Wildlife and Fisheries 12 2012-10-01 2012-10-01 false Black sea bass minimum fish sizes. 648... Measures for the Black Sea Bass Fishery § 648.147 Black sea bass minimum fish sizes. (a) Moratorium (commercially) permitted vessels. The minimum size for black sea bass is 11 inches (27.94 cm) total length for...
50 CFR 648.141 - Black sea bass Annual Catch Target (ACT).
Code of Federal Regulations, 2012 CFR
2012-10-01
... 50 Wildlife and Fisheries 12 2012-10-01 2012-10-01 false Black sea bass Annual Catch Target (ACT... Management Measures for the Black Sea Bass Fishery § 648.141 Black sea bass Annual Catch Target (ACT). (a) The Black Sea Bass Monitoring Committee shall identify and review the relevant sources of management...
50 CFR 648.140 - Black sea bass Annual Catch Limit (ACL).
Code of Federal Regulations, 2013 CFR
2013-10-01
... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Black sea bass Annual Catch Limit (ACL... Management Measures for the Black Sea Bass Fishery § 648.140 Black sea bass Annual Catch Limit (ACL). (a) The Black Sea Bass Monitoring Committee shall recommend to the MAFMC separate ACLs for the commercial and...
50 CFR 648.146 - Black sea bass recreational fishing season.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Black sea bass recreational fishing... Management Measures for the Black Sea Bass Fishery § 648.146 Black sea bass recreational fishing season... possession limit specified in § 648.145(a), may only possess black sea bass from May 19 through September 21...
50 CFR 648.140 - Black sea bass Annual Catch Limit (ACL).
Code of Federal Regulations, 2012 CFR
2012-10-01
... 50 Wildlife and Fisheries 12 2012-10-01 2012-10-01 false Black sea bass Annual Catch Limit (ACL... Management Measures for the Black Sea Bass Fishery § 648.140 Black sea bass Annual Catch Limit (ACL). (a) The Black Sea Bass Monitoring Committee shall recommend to the MAFMC separate ACLs for the commercial and...
50 CFR 648.147 - Black sea bass minimum fish sizes.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Black sea bass minimum fish sizes. 648... Measures for the Black Sea Bass Fishery § 648.147 Black sea bass minimum fish sizes. (a) Moratorium (commercially) permitted vessels. The minimum size for black sea bass is 11 inches (27.94 cm) total length for...
50 CFR 648.145 - Black sea bass possession limit.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 50 Wildlife and Fisheries 12 2014-10-01 2014-10-01 false Black sea bass possession limit. 648.145... Measures for the Black Sea Bass Fishery § 648.145 Black sea bass possession limit. (a) During the recreational fishing season specified at § 648.146, no person shall possess more than 15 black sea bass in, or...
50 CFR 648.145 - Black sea bass possession limit.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 50 Wildlife and Fisheries 12 2012-10-01 2012-10-01 false Black sea bass possession limit. 648.145... Measures for the Black Sea Bass Fishery § 648.145 Black sea bass possession limit. (a) From January 1 through February 28, no person shall possess more than 15 black sea bass in, or harvested from, the EEZ...
50 CFR 648.145 - Black sea bass possession limit.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Black sea bass possession limit. 648.145... Measures for the Black Sea Bass Fishery § 648.145 Black sea bass possession limit. (a) During the recreational fishing season specified at § 648.146, no person shall possess more than 20 black sea bass in, or...
50 CFR 648.146 - Black sea bass recreational fishing season.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 50 Wildlife and Fisheries 12 2013-10-01 2013-10-01 false Black sea bass recreational fishing... Management Measures for the Black Sea Bass Fishery § 648.146 Black sea bass recreational fishing season... possession limit specified in § 648.145(a), may only possess black sea bass from May 19 through October 14...
Comparison of Smoking Habits of Blacks and Whites in a Case-Control Study.
ERIC Educational Resources Information Center
Kabat, Geoffrey C.; And Others
1991-01-01
Subjects were interviewed to determine smoking habits of 9,252 current cigarette smokers (11 percent black) and 7,555 former smokers (6 percent black). More blacks than whites smoked. Blacks were three times more likely to be light smokers than heavy smokers. Effective prevention may require better understanding of cultural factors affecting…
ERIC Educational Resources Information Center
Rollock, Nicola
2007-01-01
The continued lower academic attainment of Black (especially Black Caribbean) pupils is now well established. Yet, to date there has been no single coherent national Government strategy that has successfully closed the gap in educational attainment between either Black and White pupils or between Black pupils and the national average. Academic and…
Why Are Black Employers More Likely Than White Employers To Hire Blacks? Discussion Paper.
ERIC Educational Resources Information Center
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…
Towards a Theory of Selected Knowledge Acquisition Patterns Among Black Children.
ERIC Educational Resources Information Center
Morgan, Harry
The contention that among black people there is a cognitive style which seems to require a more active intervention with the learning environment than what is needed by their white counterpart is advanced in this discussion of cognitive style among black Africans and black Americans. Cognitive styles of blacks in the infant, early school, and…
Density and abundance of black-backed woodpeckers in a Ponderosa pine ecosystem
Sean R. Mohren; Mark A. Rumble; Stanley H. Anderson
2014-01-01
Black-backed woodpeckers (Picoides arcticus) are usually associated with forest disturbance resulting in recently killed trees. While black-backed woodpeckers are attracted to areas affected by these disturbances, in the Black Hills they exist during interim disturbance periods in largely undisturbed forests. In 2012, a petition for listing black-backed woodpeckers in...
Tempered Radicals and Servant Leaders: Black Females Persevering in the Superintendency
ERIC Educational Resources Information Center
Alston, Judy A.
2005-01-01
Despite the small numbers of Black female superintendents and the overwhelming obstacles of the position, Black women who serve as public school superintendents continue to meet the challenges of educational leadership and are flourishing in their jobs. As noted in previous research on Black women in the superintendency and Black female leaders in…
Intergroup Stereotypes of Working Class Blacks and Whites: Implications for Stereotype Threat.
ERIC Educational Resources Information Center
Niemann, Yolanda Flores; O'Connor, Elizabeth; McClorie, Randall
1998-01-01
Examined stereotypes of urban blacks and whites at a flea market with 68 black respondents, and at another flea market with 20 white respondents. Cluster-analysis results show that blacks have a relatively complex, multidimensional representation of themselves and of whites, while whites seem to have a more simplistic and negative view of blacks.…
Slow-motion scattering and coalescence of maximally charged black holes
NASA Technical Reports Server (NTRS)
Ferrell, Robert C.; Eardley, Douglas M.
1987-01-01
Systems consisting of several maximally charged, nonrotating black holes ('Reissner-Nordstrom' black holes) interacting with one another are studied. An effective action for the system in the slow-motion, fully strong-field regime is presented. An exact calculation of black-hole-black-hole scattering and coalescence in the slow-motion (but strong-field) limit is given.
Counseling Strategies with Black Boys and Black Men: Implications for Policy
ERIC Educational Resources Information Center
Harper, Frederick D.; Terry, Linda M.; Twiggs, Rashida
2009-01-01
The article discusses behavioral and sociodemographic conditions of Black males in the U.S. and presents counseling strategies, prevention programs and efforts, and recommendations for practice and policy as means of helping Black boys and Black men to minimize and transcend the challenges within U.S. culture and within themselves. In addition,…
We Dream a World: The 2025 Vision for Black Men and Boys
ERIC Educational Resources Information Center
Tsoi-A-Fatt, Rhonda
2010-01-01
Black men are vital and important members of American society, especially in their communities. Black families suffer a great loss when Black men are unable to thrive. Throughout modern American history, Black men have struggled to gain their footing and fulfill their destinies as strong, caring and productive members of society and their…
ERIC Educational Resources Information Center
Brown, Corliss Charonne
2013-01-01
In recent years, there has been an increasing focus on preparing educators to teach for social justice. Black teachers have been highlighted for their historical and present work with black students, eliminating educational inequities seemingly through their race consciousness and activism. The literature on black teachers has treated them as a…
ERIC Educational Resources Information Center
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.
ERIC Educational Resources Information Center
Farinde, Abiola A.; Allen, Ayana; Lewis, Chance W.
2016-01-01
Sixty years after "Brown v. Board of Education," retention trends indicate that there is a Black teacher shortage. Research shows that Black teachers' retention rates are often lower than the retention rates of White teachers. Black teachers report low salaries, lack of administrative support, and other school variables as reasons for…
ERIC Educational Resources Information Center
Daoud, Nina; English, Shelvia; Griffin, Kimberly A.; Mwangi, Chrystal A. George
2018-01-01
This qualitative case study examines 43 black students' understanding of the relationships of social identity, academic identity, and college-going aspirations. Specifically, we focus on understanding how stereotypes influence the academic motivation of black immigrant and black native-born students. Findings suggest distinctions across ethnicity…
ERIC Educational Resources Information Center
Hines, Dorothy E.; Wilmot, Jennifer M.
2018-01-01
School is a hyperviolent space for Black students and in particular for Black girls. Black girls continue to be adultified, criminalized, and spirit-murdered by educators who enact racially discriminatory school disciplinary policies. Using literature from racial microaggressions and antiblackness, we introduce a model that we refer to as…
ERIC Educational Resources Information Center
Dancy, T. Elon, II; Edwards, Kirsten T.; Earl Davis, James
2018-01-01
In this article, the authors argue that U.S. colleges and universities must grapple with persistent engagements of Black bodies as property. Engaging the research and scholarship on Black faculty, staff, and students, we explain how theorizations of settler colonialism and anti-Blackness (re)interpret the arrangement between historically White…
"The Discipline Stop": Black Male Teachers and the Politics of Urban School Discipline
ERIC Educational Resources Information Center
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…
Developing the next Generation of Black and Global Majority Leaders for London Schools
ERIC Educational Resources Information Center
Johnson, Lauri; Campbell-Stephens, Rosemary
2013-01-01
Purpose: The aim of this paper is to discuss the views of black and ethnic minority school leaders about the "Investing in Diversity" program, a black-led program developed in 2004 to address the underrepresentation of black leaders in the London schools. Major themes are identified from interviews with black and South Asian women…
Black Coaches and Their Perspectives on the Black Coaches and Administrators: A Qualitative Analysis
ERIC Educational Resources Information Center
Kelly, Daniel G., II; Pastore, Donna L.; Hodge, Samuel R.; Seifried, Chad
2015-01-01
The purpose of this study was to analyze Black male collegiate coaches' understandings and perspectives about building a coaching career in NCAA Division I athletics and the function of the Black Coaches and Administrators (BCA) as a mechanism to help facilitate more coaching opportunities. The participants were seven Black male assistant coaches…
Thomas W. Bonnot; Mark A. Rumble; Joshua J. Millspaugh
2008-01-01
Black-backed Woodpeckers (Picoides arcticus) are burned-forest specialists that rely on beetles (Coleoptera) for food. In the Black Hills, South Dakota, standing dead forests resulting from mountain pine beetle (Dendroctonus ponderosae) outbreaks offer food resources for Black-backed Woodpeckers, in addition to providing habitat...
The Use and Performance of Hymnody, Spirituals, and Gospels in the Black Church.
ERIC Educational Resources Information Center
Maultsby, Portia K.
1983-01-01
Explores use and performance of music in the Black church through examination of (1) the events that led to the conversion of Blacks to Christianity; (2) the formation of independent Black religious groups; and (3) the social and cultural milieu that fostered the development of a unique Black religious music. (Author/ML)
ERIC Educational Resources Information Center
Gaines, Nykia Dionne
2012-01-01
International education helps students become more engaged within the United States and abroad. Black undergraduates continue to be underrepresented in study abroad despite two decades of increased enrollment by Black students in higher education in the United States. This study had three purposes: (1) to explore how Black undergraduates attending…
The Self-Efficacy Beliefs of Black Women Leaders in Fortune 500 Companies
ERIC Educational Resources Information Center
Jackson, LaTonya R.
2012-01-01
Black women are underrepresented in leadership positions within organizations. The extent to which self-efficacy influences the advancement potential of Black females is unknown. The purpose of this study was to examine the self-efficacy beliefs of black women in leadership positions and to determine how Black women leaders' careers are…
Black Families and the Struggle for Survival.
ERIC Educational Resources Information Center
Billingsley, Andrew; And Others
Breaking away from those who see the structure of family life in the black community as pathological, this study wishes to assist a lay audience in identifying the strengths of black families. The book provides both insights and resources for engaging churches and black families in the common task of enhancing black family life. Where the church's…
Simulations of nearly extremal binary black holes
NASA Astrophysics Data System (ADS)
Giesler, Matthew; Scheel, Mark; Hemberger, Daniel; Lovelace, Geoffrey; Kuper, Kevin; Boyle, Michael; Szilagyi, Bela; Kidder, Lawrence; SXS Collaboration
2015-04-01
Astrophysical black holes could have nearly extremal spins; therefore, nearly extremal black holes could be among the binaries that current and future gravitational-wave observatories will detect. Predicting the gravitational waves emitted by merging black holes requires numerical-relativity simulations, but these simulations are especially challenging when one or both holes have mass m and spin S exceeding the Bowen-York limit of S /m2 = 0 . 93 . Using improved methods we simulate an unequal-mass, precessing binary black hole coalescence, where the larger black hole has S /m2 = 0 . 99 . We also use these methods to simulate a nearly extremal non-precessing binary black hole coalescence, where both black holes have S /m2 = 0 . 994 , nearly reaching the Novikov-Thorne upper bound for holes spun up by thin accretion disks. We demonstrate numerical convergence and estimate the numerical errors of the waveforms; we compare numerical waveforms from our simulations with post-Newtonian and effective-one-body waveforms; and we compare the evolution of the black-hole masses and spins with analytic predictions.
Thermodynamic phase transition in the rainbow Schwarzschild black hole
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gim, Yongwan; Kim, Wontae, E-mail: yongwan89@sogang.ac.kr, E-mail: wtkim@sogang.ac.kr
2014-10-01
We study the thermodynamic phase transition in the rainbow Schwarzschild black hole where the metric depends on the energy of the test particle. Identifying the black hole temperature with the energy from the modified dispersion relation, we obtain the modified entropy and thermodynamic energy along with the modified local temperature in the cavity to provide well defined black hole states. It is found that apart from the conventional critical temperature related to Hawking-Page phase transition there appears an additional critical temperature which is of relevance to the existence of a locally stable tiny black hole; however, the off-shell free energymore » tells us that this black hole should eventually tunnel into the stable large black hole. Finally, we discuss the reason why the temperature near the horizon is finite in the rainbow black hole by employing the running gravitational coupling constant, whereas it is divergent near the horizon in the ordinary Schwarzschild black hole.« less
Thermodynamics, stability and Hawking-Page transition of Kerr black holes from Rényi statistics
NASA Astrophysics Data System (ADS)
Czinner, Viktor G.; Iguchi, Hideo
2017-12-01
Thermodynamics of rotating black holes described by the Rényi formula as equilibrium and zeroth law compatible entropy function is investigated. We show that similarly to the standard Boltzmann approach, isolated Kerr black holes are stable with respect to axisymmetric perturbations in the Rényi model. On the other hand, when the black holes are surrounded by a bath of thermal radiation, slowly rotating black holes can also be in stable equilibrium with the heat bath at a fixed temperature, in contrast to the Boltzmann description. For the question of possible phase transitions in the system, we show that a Hawking-Page transition and a first order small black hole/large black hole transition occur, analogous to the picture of rotating black holes in AdS space. These results confirm the similarity between the Rényi-asymptotically flat and Boltzmann-AdS approaches to black hole thermodynamics in the rotating case as well. We derive the relations between the thermodynamic parameters based on this correspondence.
Remarks on non-singular black holes
NASA Astrophysics Data System (ADS)
Frolov, Valeri P.
2018-01-01
We briefly discuss non-singular black hole models, with the main focus on the properties of non-singular evaporating black holes. Such black holes possess an apparent horizon, however the event horizon may be absent. In such a case, the information from the black hole interior may reach the external observer after the complete evaporation of the black hole. This model might be used for the resolution of the information loss puzzle. However, as we demonstrate, in a general case the quantum radiation emitted from the black hole interior, calculated in the given black hole background, is very large. This outburst of the radiation is exponentially large for models with the redshift function α = 1. We show that it can be suppressed by including a non-trivial redshift function. However, even this suppression is not enough to guarantee self-consistency of the model. This problem is a manifestation of a general problem, known as the "mass inflation". We briefly comment on possible ways to overcome this problem in the models of non-singular evaporating black holes.
Charged black rings at large D
NASA Astrophysics Data System (ADS)
Chen, Bin; Li, Peng-Cheng; Wang, Zi-zhi
2017-04-01
We study the charged slowly rotating black holes in the Einstein-Maxwell theory in the large dimensions ( D). By using the 1 /D expansion in the near regions of the black holes we obtain the effective equations for the charged slowly rotating black holes. The effective equations capture the dynamics of various stationary solutions, including the charged black ring, the charged slowly rotating Myers-Perry black hole and the charged slowly boosted black string. Via different embeddings we construct these stationary solutions explicitly. For the charged black ring at large D, we find that the charge lowers the angular momentum due to the regularity condition on the solution. By performing the perturbation analysis of the effective equations, we obtain the quasinormal modes of the charge perturbation and the gravitational perturbation analytically. Like the neutral case the charged thin black ring suffers from the Gregory-Laflamme-like instability under the non-axisymmetric perturbations, but the charge weakens the instability. Besides, we find that the large D analysis always respects the cosmic censorship.
Evolution and End Point of the Black String Instability: Large D Solution.
Emparan, Roberto; Suzuki, Ryotaku; Tanabe, Kentaro
2015-08-28
We derive a simple set of nonlinear, (1+1)-dimensional partial differential equations that describe the dynamical evolution of black strings and branes to leading order in the expansion in the inverse of the number of dimensions D. These equations are easily solved numerically. Their solution shows that thin enough black strings are unstable to developing inhomogeneities along their length, and at late times they asymptote to stable nonuniform black strings. This proves an earlier conjecture about the end point of the instability of black strings in a large enough number of dimensions. If the initial black string is very thin, the final configuration is highly nonuniform and resembles a periodic array of localized black holes joined by short necks. We also present the equations that describe the nonlinear dynamics of anti-de Sitter black branes at large D.
Planckian charged black holes in ultraviolet self-complete quantum gravity
NASA Astrophysics Data System (ADS)
Nicolini, Piero
2018-03-01
We present an analysis of the role of the charge within the self-complete quantum gravity paradigm. By studying the classicalization of generic ultraviolet improved charged black hole solutions around the Planck scale, we showed that the charge introduces important differences with respect to the neutral case. First, there exists a family of black hole parameters fulfilling the particle-black hole condition. Second, there is no extremal particle-black hole solution but quasi extremal charged particle-black holes at the best. We showed that the Hawking emission disrupts the condition of particle-black hole. By analyzing the Schwinger pair production mechanism, the charge is quickly shed and the particle-black hole condition can ultimately be restored in a cooling down phase towards a zero temperature configuration, provided non-classical effects are taken into account.
Johnson, James D; Olivo, Nelgy; Gibson, Nathan; Reed, William; Ashburn-Nardo, Leslie
2009-04-01
Two experiments involving White participants tested the influence of media-based priming of Black stereotypes on support for government policy that assisted Black versus White persons-in-need. Experiment 1 showed that priming the "Black criminal" stereotype through exposure to photographs of Blacks looting after Hurricane Katrina reduced policy support for Black evacuees-in-need but did not influence support responses toward White evacuees-in-need. Experiment 2 showed that priming the "promiscuous Black female" stereotype through exposure to sexual rap music reduced policy support for a Black pregnant woman-in-need but did not influence support responses toward a White pregnant woman-in-need. Further tests of mediated moderation demonstrated that in both experiments, the interactive influence of priming Black stereotypes and race of persons-in-need on policy support was mediated by empathic responding.
Exposure to smoking in movies and smoking initiation among black youth.
Dal Cin, Sonya; Stoolmiller, Mike; Sargent, James D
2013-04-01
Black adolescents see more substance use in mainstream media but seem less responsive to it than other U.S. adolescents. Black-oriented media may be more personally relevant to them. To determine smoking exposure separately for black-oriented (BSME) and mainstream (MMSE) movies and assess their longitudinal relationships with smoking among black and other-race adolescents. Two-wave (2007-2009) national cohort survey of 2341 nonsmoking (at baseline) U.S. adolescents (aged 13-19 years), analyzed in 2012. The surveys determined BMSE and MMSE based on respondents' exposure to random subsets of 50 movies from a contemporary sample of 95 black-oriented and 288 mainstream movies previously content-coded for smoking. Outcome was smoking initiation. Black teens had significantly more BMSE and MMSE than other teens (p's <0.001). At follow-up, 23.5% of black and 29.0% of nonblack respondents had tried smoking. Among black respondents, BMSE was related to smoking initiation at follow-up but MMSE was not. For other adolescents, both BMSE and MMSE were related to smoking initiation. A prospective relationship was found between exposure to smoking in movies and smoking initiation. Among black adolescents in the U.S., this was only for black-oriented movies, suggesting the importance of personal relevance of the exposures. Parents, practitioners, and producers should be aware of these potential influences of media on black teen viewers. Copyright © 2013 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.
Phelps, Q.E.; Ward, M.J.; Paukert, C.P.; Chipps, S.R.; Willis, D.W.
2005-01-01
We explored relationships among black bullhead (Ameiurus melas) population characteristics and physicochemical attributes in shallow lakes and quantified relationships between population characteristics of black bullhead and sport fishes. Lake characteristics and fisheries survey data were collected from the Sandhills region of northcentral Nebraska from May through June, 1998 and 1999. Relative abundance of black bullheads was inversely related to proportional stock density (r=-0.672, df=15, P=0.004); however, neither relative weight nor growth was significantly (P ??? 0.20) related to black bullhead relative abundance. Population characteristics of common panfish species such as bluegill (Lepomis macrochirus), green sunfish (L. cyanellus), pumpkinseed (L. gibbosus), and yellow perch (Perca flavescens) were not correlated with black bullhead relative abundance or size structure. Rather, proportional stock density (r=0.655, df=10, P=0.029) and growth (r=0.59, df=11, P=0.04) of black bullhead were positively related to relative abundance of largemouth bass (Micropterus salmoides). Similarly, black bullhead relative abundance was inversely related to largemouth bass size structure (r=-0.51, df=14, P= 0.05). Black bullhead mean length at age 3 was positively related to total phosphorous concentration (r=0.65, df=16, P=0.004), and bullhead relative abundance was positively related to shoreline development index (r=0.46, df=22, P=0.03). Population characteristics of black bullhead appeared to have little influence on panfish communities. Rather, black bullhead abundance, predator density, and lake productivity exhibited stronger relationships with black bullhead population characteristics.
Shadows of rotating five-dimensional charged EMCS black holes
NASA Astrophysics Data System (ADS)
Amir, Muhammed; Singh, Balendra Pratap; Ghosh, Sushant G.
2018-05-01
Higher-dimensional theories admit astrophysical objects like supermassive black holes, which are rather different from standard ones, and their gravitational lensing features deviate from general relativity. It is well known that a black hole shadow is a dark region due to the falling geodesics of photons into the black hole and, if detected, a black hole shadow could be used to determine which theory of gravity is consistent with observations. Measurements of the shadow sizes around the black holes can help to evaluate various parameters of the black hole metric. We study the shapes of the shadow cast by the rotating five-dimensional charged Einstein-Maxwell-Chern-Simons (EMCS) black holes, which is characterized by four parameters, i.e., mass, two spins, and charge, in which the spin parameters are set equal. We integrate the null geodesic equations and derive an analytical formula for the shadow of the five-dimensional EMCS black hole, in turn, to show that size of black hole shadow is affected due to charge as well as spin. The shadow is a dark zone covered by a deformed circle, and the size of the shadow decreases with an increase in the charge q when compared with the five-dimensional Myers-Perry black hole. Interestingly, the distortion increases with charge q. The effect of these parameters on the shape and size of the naked singularity shadow of the five-dimensional EMCS black hole is also discussed.
Dynamical Formation Signatures of Black Hole Binaries in the First Detected Mergers by LIGO
NASA Astrophysics Data System (ADS)
O'Leary, Ryan M.; Meiron, Yohai; Kocsis, Bence
2016-06-01
The dynamical formation of stellar-mass black hole-black hole binaries has long been a promising source of gravitational waves for the Laser Interferometer Gravitational-Wave Observatory (LIGO). Mass segregation, gravitational focusing, and multibody dynamical interactions naturally increase the interaction rate between the most massive black holes in dense stellar systems, eventually leading them to merge. We find that dynamical interactions, particularly three-body binary formation, enhance the merger rate of black hole binaries with total mass M tot roughly as \\propto {M}{{tot}}β , with β ≳ 4. We find that this relation holds mostly independently of the initial mass function, but the exact value depends on the degree of mass segregation. The detection rate of such massive black hole binaries is only further enhanced by LIGO’s greater sensitivity to massive black hole binaries with M tot ≲ 80 {M}⊙ . We find that for power-law BH mass functions dN/dM ∝ M -α with α ≤ 2, LIGO is most likely to detect black hole binaries with a mass twice that of the maximum initial black hole mass and a mass ratio near one. Repeated mergers of black holes inside the cluster result in about ˜5% of mergers being observed between two and three times the maximum initial black hole mass. Using these relations, one may be able to invert the observed distribution to the initial mass function with multiple detections of merging black hole binaries.
Exposure to Smoking in Movies and Smoking Initiation Among Black Youth
Dal Cin, Sonya; Stoolmiller, Mike; Sargent, James D.
2013-01-01
Background Black adolescents see more substance use in mainstream media but seem less responsive to it than other U.S. adolescents. Black-oriented media may be more personally relevant to them. Purpose To determine smoking exposure separately for black-oriented (BSME) and mainstream (MMSE) movies and assess their longitudinal relationships with smoking among black and other-race adolescents. Methods Two-wave (2007–2009) national cohort survey of 2341 nonsmoking (at baseline) U.S. adolescents (aged 13–19 years), analyzed in 2012. The surveys determined BMSE and MMSE based on respondents’ exposure to random subsets of 50 movies from a contemporary sample of 95 black-oriented and 288 mainstream movies previously content-coded for smoking. Outcome was smoking initiation. Results Black teens had significantly more BMSE and MMSE than other teens (p’s <0.001). At follow-up, 23.5% of black and 29.0% of nonblack respondents had tried smoking. Among black respondents, BMSE was related to smoking initiation at follow-up but MMSE was not. For other adolescents, both BMSE and MMSE were related to smoking initiation. Conclusions A prospective relationship was found between exposure to smoking in movies and smoking initiation. Among black adolescents in the U.S., this was only for black-oriented movies, suggesting the importance of personal relevance of the exposures. Parents, practitioners, and producers should be aware of these potential influences of media on black teen viewers. PMID:23498099
Assessing black progress: voting and citizenship rights, residency and housing, education.
Farley, R
1986-01-01
Farley discusses progress US blacks have made in the areas of voting and citizenship rights, residency and housing, and education. A major goal of the civil rights movement was to permit blacks to influence the electoral process in the same manner as whites. Most important in this regard was the Voting Rights Act of 1965; the proportion of southern blacks casting ballots increased sharply since the early 1960s. The Civil Rights Act of 1875 outlawed racial segregation in public accommodations, but by the turn of the century, Jim Crow laws in southern states called for segregation in most public places. Common customs and government policy in the North resulted in similar segregation of blacks from whites. The Montgomery bus boycott and similar protests in dozens of other cities led to enactment of Title II of the Civil Rights Act of 1964, which proscribed such racial practices. By the late 1960s, blacks in all regions could use the same public accommodations as whites. In most metropolitan areas, de facto racial segregation persisted long after the laws were changed. Supreme Court decisions and local open-housing ordinances supported the right of blacks to live where they could afford. However the major change was the Fair Housing Act of 1968, which outlawed racial discrimination in the sale or rental of most housing units. The separation of blacks from whites did not end in the 1970s. Today, in areas which have large black populations, there are many central city neighborhoods and a few in the suburbs which are either all-black or are becoming exclusively black enclaves. Most other neighborhoods have no more than token black populations. Another major effort of civil rights organizations has been the upgrading of housing quality for blacks. By 1980, only 6% of the homes and apartments occupied by blacks lacked complete plumbing facilities (down from 50% in 1940). Unlike the modest changes in residential segregation, racial differences in housing quality have been greatly reduced. By 1960, black students approached parity with whites in terms of measurable aspects of school facilities. In 1940, young blacks averaged about 3 fewer years of educational attainment than whites; the time is nearing when the years of schooling completed by blacks and whites will be the same. In small and medium-sized cities throughout the country, public schools are generally integrated. However, the situation in the largest metropolitan areas is very different. Today, large public schools are segregated, in large part, because blacks and whites live in separate school districts.
Boosting jet power in black hole spacetimes.
Neilsen, David; Lehner, Luis; Palenzuela, Carlos; Hirschmann, Eric W; Liebling, Steven L; Motl, Patrick M; Garrett, Travis
2011-08-02
The extraction of rotational energy from a spinning black hole via the Blandford-Znajek mechanism has long been understood as an important component in models to explain energetic jets from compact astrophysical sources. Here we show more generally that the kinetic energy of the black hole, both rotational and translational, can be tapped, thereby producing even more luminous jets powered by the interaction of the black hole with its surrounding plasma. We study the resulting Poynting jet that arises from single boosted black holes and binary black hole systems. In the latter case, we find that increasing the orbital angular momenta of the system and/or the spins of the individual black holes results in an enhanced Poynting flux.
Closing the Educational Achievement Gap between Blacks and Whites: Nobody Wants to Be Black
ERIC Educational Resources Information Center
Scott, Austin L.; Kronick, Robert
2006-01-01
This research study attempts to explain the educational achievement gap between blacks and whites, the factors that cause the achievement gap, the consequences of the achievement gap for the black race, and possible solutions to the achievement gap. The data collected for this study has shown that the educational achievement gap between blacks and…
ERIC Educational Resources Information Center
Gordon, Megan K.; Zinga, Dawn M.
2012-01-01
The black-focused school introduced by the Toronto District School Board (TDSB) in 2009 has been controversial since the community consultations were conducted. Although media representations and Dei (1996, 2006) provide insight into what Torontonians' reactions are to the proposed black-focused school, the reactions of black youth in the Greater…
ERIC Educational Resources Information Center
Detroit Public Schools, MI. Dept. of Curriculum Development Services.
Activities and resources used in observance of Black History Month (February, 1984) are presented. Although much of the document focuses on Detroit, Michigan, the guide can be used as a model for black history observance in other states. Following specific suggestions for school and individual observance of Black History Month, the guide presents…
Once a Year to Be Black: Fighting against Typical Black History Month Pedagogies
ERIC Educational Resources Information Center
King, LaGarrett J.; Brown, Keffrelyn
2014-01-01
Our study examined the experiences of three middle school teachers who created their own Black History Month curriculum. Although, the relevance of Black History Month is under scrutiny by opponents who feel it marginalized the history of Black Americans, proponents of this position have failed: to account for teachers who view and use this Month…
ERIC Educational Resources Information Center
Henry, Wilma J.; Closson, Rosemary B.
2012-01-01
Focus groups were used in the present study to explore the racial identity development of Black male and White male student-athletes on a predominantly Black, Division IA football team at a predominantly White institution (PWI). Findings indicate that the Black male football players demonstrated positive indicators of Black racial identity. The…
ERIC Educational Resources Information Center
Rankins, Falcon
2017-01-01
This qualitative inquiry explored the ways in which US-born, Black faculty member participants in science, technology, engineering, and mathematics (STEM) disciplines at Historically Black Colleges and Universities (HBCUs) interact with the National Science Foundation (NSF). Eight Black HBCU STEM faculty members with a range of involvement in…
From Black Power to Black Studies: How a Radical Social Movement became an Academic Discipline
ERIC Educational Resources Information Center
Rojas, Fabio
2007-01-01
The black power movement helped redefine African Americans' identity and establish a new racial consciousness in the 1960s. As an influential political force, this movement in turn spawned the academic discipline known as Black Studies. Today there are more than a hundred Black Studies degree programs in the United States, many of them located in…
26 CFR 1.501(c)(21)-1 - Black lung trusts-certain terms.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 26 Internal Revenue 7 2013-04-01 2013-04-01 false Black lung trusts-certain terms. 1.501(c)(21)-1...) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Exempt Organizations § 1.501(c)(21)-1 Black lung trusts... insurer or guarantor of the liabilities of another. (c) Black Lung Acts. The term Black Lung Acts includes...
26 CFR 1.501(c)(21)-1 - Black lung trusts-certain terms.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 26 Internal Revenue 7 2014-04-01 2013-04-01 true Black lung trusts-certain terms. 1.501(c)(21)-1...) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Exempt Organizations § 1.501(c)(21)-1 Black lung trusts... insurer or guarantor of the liabilities of another. (c) Black Lung Acts. The term Black Lung Acts includes...
26 CFR 1.501(c)(21)-1 - Black lung trusts-certain terms.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 26 Internal Revenue 7 2011-04-01 2009-04-01 true Black lung trusts-certain terms. 1.501(c)(21)-1...) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Exempt Organizations § 1.501(c)(21)-1 Black lung trusts... insurer or guarantor of the liabilities of another. (c) Black Lung Acts. The term Black Lung Acts includes...
26 CFR 1.501(c)(21)-1 - Black lung trusts-certain terms.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 26 Internal Revenue 7 2012-04-01 2012-04-01 false Black lung trusts-certain terms. 1.501(c)(21)-1...) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Exempt Organizations § 1.501(c)(21)-1 Black lung trusts... insurer or guarantor of the liabilities of another. (c) Black Lung Acts. The term Black Lung Acts includes...
The Black Rural Landowner: Endangered Species, Social, Political and Economic Implications.
ERIC Educational Resources Information Center
McGee, Leo, Ed.; Boone, Robert, Ed.
This publication discusses the issue of black owned rural land decline. Since the turn of the century, it is estimated that blacks have lost in excess of 9,000,000 acres of rural land. The impact of this loss is tremendous for blacks, both on the economic and psychological levels. Developing strategies to arrest the rapid decline of black owned…
Agrobacterium-mediated transformation of black cherry for flowering control and insect resistance
Ying Wang; Paula M. Pijut
2014-01-01
Black cherry is one of the most valuable hardwood species for cabinetry, furniture, and veneer. The goal of this study was to develop transgenic black cherry plants with reproductive sterility and enhanced insect resistance. Black cherry TERMINAL FLOWER 1 (PsTFL1) was overexpressed under the control of the CaMV 35S promoter in black cherry via
ERIC Educational Resources Information Center
Power, Marshall I.
1986-01-01
Comparison of intragenerational mobility of black and white men shows the following: (1) black upward mobility is less frequent and more restricted; (2) blacks within the public sector have substantial rates of upward mobility to nonmanagerial positions; and (3) discrimination against blacks in the labor market has not disappeared. (Author/PS)
ERIC Educational Resources Information Center
Lundy-Wagner, Valerie C.
2013-01-01
Efforts to improve the Black science, technology, engineering and mathematics (STEM) pipeline have focused on historically Black colleges and universities (HBCUs); however, this work generally fails to acknowledge men. This article characterized Black male receipts of bachelor's degrees from HBCUs in STEM fields between 1981 and 2009 using a…
ERIC Educational Resources Information Center
Marbury, Carl H.
This paper reviews the role of the black church in black American history and suggests ways in which its role must change to help blacks cope with our modern and technological society. Initially, religion was the one social institution which gave black slaves a common tie before the Civil War. Baptist and Methodist ideologies provided emotional…
ERIC Educational Resources Information Center
Tillman, Linda C.
2004-01-01
The displacement of Black educators after the "Brown v. Board of Education" decision was an extraordinary social injustice. The wholesale firing of Black educators threatened the economic, social, and cultural structure of the Black community, and ultimately the social, emotional, and academic success of Black children. The author presents a…
ERIC Educational Resources Information Center
Aston, Candice N.
2017-01-01
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…
The Black Kitchen Table Agreement: The Power of Silence during The Era of Trump
ERIC Educational Resources Information Center
Williams, Nathaniel Andrew
2017-01-01
The Black kitchen table has long served as a meeting place for Black families to discuss, debate, and critique issues related to the Black struggle. In particular, it was common for Black kitchen table conversations to talk about the nuances of navigating systems of legalized segregation and oppression, as well--and more recently--navigating the…
ERIC Educational Resources Information Center
Chapman-Hilliard, Collette; Beasley, Samuel T.
2018-01-01
This study examined Black students' experiences in culture-centered courses that focused on the historical and contemporary experiences of Blacks in America and across the African diaspora. Using a qualitative approach, the authors investigated the perceptions of how Black Studies courses shaped the psychosocial experiences and identity…
"I'm Still Here:" Black Female Undergraduates' Self-Definition Narratives
ERIC Educational Resources Information Center
Robinson, Subrina J.; Esquibel, Elena; Rich, Marc D.
2013-01-01
Drawing on Black feminism and oral narrative research, we examine how Black women undergraduates make sense of their identities as Black females. More specifically, we explore the dual impact of gender and race by considering what it means to be a Black woman on campus. The women in this study articulate compelling, and at times, diverging…
What the White "Squaws" Want from Black Hawk: Gendering the Fan-Celebrity Relationship
ERIC Educational Resources Information Center
Helton, Tena L.
2010-01-01
Americans in the East were great fans of Black Hawk, whose popularity on tour overtook that of Andrew Jackson's parallel tour of the Northeast. Undoubtedly, then, Black Hawk was a celebrity. He remained popular even in 1837, when he attended Catlin's gallery opening in New York, which included his 1832 painting of Black Hawk. Black Hawk may also…
The Striking Progress of African Americans in Degree Attainments.
ERIC Educational Resources Information Center
Journal of Blacks in Higher Education, 2002
2002-01-01
While the number of blacks earning bachelor's and master's degrees has risen significantly since 1985, and the number of black doctoral degrees rose 110 percent, the percentage of all degrees awarded to blacks at all levels is far lower than the black percentage of the U.S. population. Black women earn 65.7 percent of all doctorates awarded to…
Entanglement in a model for Hawking radiation: An application of quadratic algebras
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bambah, Bindu A., E-mail: bbsp@uohyd.ernet.in; Mukku, C., E-mail: mukku@iiit.ac.in; Shreecharan, T., E-mail: shreecharan@gmail.com
2013-03-15
Quadratic polynomially deformed su(1,1) and su(2) algebras are utilized in model Hamiltonians to show how the gravitational system consisting of a black hole, infalling radiation and outgoing (Hawking) radiation can be solved exactly. The models allow us to study the long-time behaviour of the black hole and its outgoing modes. In particular, we calculate the bipartite entanglement entropies of subsystems consisting of (a) infalling plus outgoing modes and (b) black hole modes plus the infalling modes, using the Janus-faced nature of the model. The long-time behaviour also gives us glimpses of modifications in the character of Hawking radiation. Finally, wemore » study the phenomenon of superradiance in our model in analogy with atomic Dicke superradiance. - Highlights: Black-Right-Pointing-Pointer We examine a toy model for Hawking radiation with quantized black hole modes. Black-Right-Pointing-Pointer We use quadratic polynomially deformed su(1,1) algebras to study its entanglement properties. Black-Right-Pointing-Pointer We study the 'Dicke Superradiance' in black hole radiation using quadratically deformed su(2) algebras. Black-Right-Pointing-Pointer We study the modification of the thermal character of Hawking radiation due to quantized black hole modes.« less
Effects of temperature on the quality of black garlic.
Zhang, Xinyan; Li, Ningyang; Lu, Xiaoming; Liu, Pengli; Qiao, Xuguang
2016-05-01
Black garlic is a type of garlic product that is generally produced by heating raw garlic at high temperature with controlled humidity for more than 30 days. Black garlic has appeared on the market for many years. It is crucial to investigate the characteristics of quality formation of black garlic during processing at various temperatures. In this study, fresh garlic was processed to black garlic at temperatures of 60, 70, 80 and 90 °C. Moisture, amino acid nitrogen and allicin contents decreased gradually during thermal processing of various temperatures. Reducing sugar, 5-hydroxymethylfurfural, total phenols, total acids contents and browning increased. The changing rate of quality indicators and flavour of black garlic varied at different temperatures. Browning intensity reached about 74 when black garlic aged. The sensory score was significantly higher in black garlic aged at 70 °C (39.95 ± 0.31) compared with that at other temperatures, suggesting that 70 °C might facilitate formation of good quality and flavour of black garlic during processing. Temperature had a remarkable impact on the quality and flavour of black garlic. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.
Black sexuality, social construction, and research targeting 'The Down Low' ('The DL').
Ford, Chandra L; Whetten, Kathryn D; Hall, Susan A; Kaufman, Jay S; Thrasher, Angela D
2007-03-01
The purpose of this commentary is to explain how social constructions of black sexuality are relevant to research targeting black sexual behavior and the ostensibly new and race-specific phenomenon known as "the Down Low" (the DL). The term "the DL" is widely used to refer to black men publicly presenting as heterosexual while secretly having sex with other men and presumably spreading human immunodeficiency virus and acquired immune deficiency syndrome (HIV/AIDS) to unsuspecting women. We briefly review lay and public health literature from 1998 to 2004 about the DL, describe existing social constructions of black sexuality, discuss two implications for epidemiologic research, and offer recommendations to guide future research. The lifestyle referenced by the term the DL is neither new nor limited to blacks, and sufficient data linking it to HIV/AIDS disparities currently are lacking. Common perceptions about the DL reflect social constructions of black sexuality as generally excessive, deviant, diseased, and predatory. Research targeting black sexual behavior that ignores these constructions may unwittingly reinforce them. Unaddressed social constructions of black sexuality have implications for epidemiologic research targeting black sexual behavior. Explicit examination of these concerns is necessary to eliminate fundamental causes of health disparities.
Black/white differences in perceived weight and attractiveness among overweight women.
Chithambo, Taona P; Huey, Stanley J
2013-01-01
Numerous studies have reported that Black women are more satisfied with their bodies than White women. The buffering hypothesis suggests that aspects of Black culture protect Black women against media ideals that promote a slender female body type; therefore, Black women are expected to exhibit higher body esteem than White women. To test this hypothesis, the current study aimed to assess the influence of race on weight perception, perceived attractiveness, and the interrelations between body mass index (BMI) and perceived attractiveness among overweight and obese women. Participants were 1,694 respondents of Wave IV of the National Longitudinal Study on Adolescent Health (M = 28.89 years). Black (n = 531) or White (n = 1163) obese or overweight women were included in the current study. As expected, Black women reported lower perceived weight and higher attractiveness than White women, despite higher body mass for Black women. Furthermore, race moderated the relationship between BMI and perceived attractiveness; for White women, a negative relationship existed between BMI and attractiveness, whereas for Black women, BMI and attractiveness were not related. The study findings provide further support for the buffering hypothesis, indicating that despite higher body mass, overweight Black women are less susceptible to thin body ideals than White women.
Black Hole Coalescence and Mergers: Review, Status, and ``Where are We Heading?''
NASA Astrophysics Data System (ADS)
Seidel, E.
I review recent progress in 3D numerical relativity, focusing onsimulations involving black holes evolved with singularity avoiding slicings. After a long series of axisymmetric and perturbative studies of distorted black holes and black hole collisions, similar studies were carried out with full 3D codes. The results show that such black hole simulations can be carried out extremely accurately, although instabilities plague the simulation at uncomfortably early times. However, new formulations of Einstein's equations allow much more stable 3D evolutions than ever before, enabling the first studies of 3D gravitational collapse to a black hole. With these new formulations, for example, it has become possible to perform the first detailed simulations of 3D grazing collisions of black holes with unequal mass and spin, and with orbital angular momentum. I discuss the 3D black hole physics that can now be studied, and prospects for the future. Such studies may be able to provide information about the final plunge of two black holes, which is relevant to gravitational wave astronomy, and will be very useful as a foundation for future studies when advanced techniques like black hole excision mature to the point that they permit full orbital coalescence simulations.
Food consumption and growth rates of juvenile black carp fed natural and prepared feeds
Hodgins, Nathaniel C.; Schramm, Harold L.; Gerard, Patrick D.
2014-01-01
The introduced mollusciphagic black carp Mylopharyngodon piceus poses a significant threat to native mollusks in temperate waters throughout the northern hemisphere, but consumption rates necessary to estimate the magnitude of impact on mollusks have not been established. We measured food consumption and growth rates for small (77–245 g) and large (466–1,071 g) triploid black carp held individually under laboratory conditions at 20, 25, and 30°C. Daily consumption rates (g food · g wet weight fish−1·d−1·100) of black carp that received prepared feed increased with temperature (small black carp 1.39–1.71; large black carp 1.28–2.10), but temperature-related increases in specific growth rate (100[ln(final weight) - ln(initial weight)]/number of days) only occurred for the large black carp (small black carp −0.02 to 0.19; large black carp 0.16–0.65). Neither daily consumption rates (5.90–6.28) nor specific growth rates (0.05–0.24) differed among temperatures for small black carp fed live snails. The results of these laboratory feeding trials indicate food consumption rates can vary from 289.9 to 349.5 J·g−1·d−1 for 150 g black carp receiving prepared feed, from 268.8 to 441.0 J·g−1·d−1for 800 g black carp receiving prepared feed, and from 84.8 to 90.2 J·g−1·d−1 for 150 g black carp that feed on snails. Applying estimated daily consumption rates to estimated biomass of native mollusks indicates that a relatively low biomass of bla
Teixeira, Bruna N; Ozdemir, Necla; Hill, Laura E; Gomes, Carmen L
2013-12-01
Previous studies have reported antimicrobial and antioxidant activity of black pepper oleoresin which is associated to its phenolic compounds and piperine. The ability of cyclodextrins to form an inclusion complex with a guest molecule could improve black pepper oleoresin application, bioavailability, and stability in foods. Hydroxypropyl beta-cyclodextrin (HPBCD) inclusion complex with black pepper olereosin were synthesized using the kneading method and characterized for its physico-chemical properties and its antioxidant and antimicrobial activities. Inclusion complex size was 103.9 ± 7.6 nm and indicated to be a polydisperse system. The entrapment efficiency was 78.3 ± 3.6%, which suggests that other constituents in black pepper oleoresin have higher affinities for HPBCD than piperine (major compound in black pepper oleoresin). Thermograms showed the disappearance of oxidation peaks of black pepper oleoresin, proving complex formation with HPBCD. Phase solubility results indicated 1:1 stoichiometric inclusion complex formation and an increase of black pepper oleoresin aqueous solubility with HPBCD concentration. Nano-encapsulation with HPBCD did not affect (P > 0.05) total phenolic content; however, it enhanced (P < 0.05) black pepper oleoresin antioxidant activity. Black pepper oleoresin and its inclusion complex were analyzed for their antimicrobial activity against Escherichia coli K12 and Salmonella enterica serovar Typhimurium LT2. Both free and encapsulated black pepper oleoresin effectively inhibited bacterial growth within the concentration range tested. Black pepper oleoresin encapsulated in HPBCD was able to inhibit Salmonella at lower (P < 0.05) concentrations than its corresponding free extract. Therefore, black pepper oleoresin-HPBCD nanocapsules could have important applications in the food industry as antimicrobial and antioxidant system. © 2013 Institute of Food Technologists®
Gafane, L F; Schutte, R; Van Rooyen, J M; Schutte, A E
2016-05-01
Low plasma renin levels and augmented cardiovascular reactivity to stress are common in blacks and have been linked to the development of hypertension in this population. We (i) compared cardiovascular and plasma renin reactivity to a cold pressor test between a black and white population; and (ii) investigated the associations between cardiovascular and plasma renin reactivity within the black and white populations. Our population consisted of 153 black and 188 white men and women (age range, 20-65 years). We measured blood pressure (BP), heart rate (HR), stroke volume (SV), total peripheral resistance (TPR), Windkessel arterial compliance, and determined plasma renin levels at rest and during the cold pressor test. Reactivity was calculated for each participant as the percentage change from the resting value. We found lower renin and elevated BP in blacks compared with whites at rest and during stress (both, P<0.001). During stress, HR increased more in blacks (P<0.001), whereas SV (P<0.001) and arterial compliance (P=0.013) decreased more in blacks compared with whites. TPR reactivity was positively associated with renin reactivity in blacks only (β=0.17; P=0.041), while in whites diastolic BP reactivity was positively associated with renin reactivity (β=0.21; P=0.005). Although blacks had suppressed renin levels at rest and during acute stress, vascular resistance reactivity associated positively with renin reactivity only in the black population. These results suggest that low renin levels in blacks during rest and stress are linked to increased peripheral vascular responses to stress, which may contribute to elevated BP in blacks.
NASA Astrophysics Data System (ADS)
Shankar, Francesco; Bernardi, Mariangela; Sheth, Ravi K.; Ferrarese, Laura; Graham, Alister W.; Savorgnan, Giulia; Allevato, Viola; Marconi, Alessandro; Läsker, Ronald; Lapi, Andrea
2016-08-01
We compare the set of local galaxies having dynamically measured black holes with a large, unbiased sample of galaxies extracted from the Sloan Digital Sky Survey. We confirm earlier work showing that the majority of black hole hosts have significantly higher velocity dispersions σ than local galaxies of similar stellar mass. We use Monte Carlo simulations to illustrate the effect on black hole scaling relations if this bias arises from the requirement that the black hole sphere of influence must be resolved to measure black hole masses with spatially resolved kinematics. We find that this selection effect artificially increases the normalization of the Mbh-σ relation by a factor of at least ˜3; the bias for the Mbh-Mstar relation is even larger. Our Monte Carlo simulations and analysis of the residuals from scaling relations both indicate that σ is more fundamental than Mstar or effective radius. In particular, the Mbh-Mstar relation is mostly a consequence of the Mbh-σ and σ-Mstar relations, and is heavily biased by up to a factor of 50 at small masses. This helps resolve the discrepancy between dynamically based black hole-galaxy scaling relations versus those of active galaxies. Our simulations also disfavour broad distributions of black hole masses at fixed σ. Correcting for this bias suggests that the calibration factor used to estimate black hole masses in active galaxies should be reduced to values of fvir ˜ 1. Black hole mass densities should also be proportionally smaller, perhaps implying significantly higher radiative efficiencies/black hole spins. Reducing black hole masses also reduces the gravitational wave signal expected from black hole mergers.
NASA Astrophysics Data System (ADS)
Shankar, Francesco; Bernardi, M.; Sheth, R. K.; Weinberg, D. H.; Miralda-Escudé, J.; Ferrarese, L.; Graham, A.; Sesana, A.; Lapi, A.; Marconi, A.; Allevato, V.; Savorgnan, G.; Laesker, R.
2016-08-01
We compare the set of local galaxies having dynamically measured black holes with a large, unbiased sample of galaxies extracted from the Sloan Digital Sky Survey. We confirm earlier work showing that the majority of black hole hosts have significantly higher velocity dispersions sigma than local galaxies of similar stellar mass. We use Monte-Carlo simulations to illustrate the effect on black hole scaling relations if this bias arises from the requirement that the black hole sphere of influence must be resolved to measure black hole masses with spatially resolved kinematics. We find that this selection effect artificially increases the normalization of the Mbh-sigma relation by a factor of at least ~3; the bias for the Mbh-Mstar relation is even larger. Our Monte Carlo simulations and analysis of the residuals from scaling relations both indicate that sigma is more fundamental than Mstar or effective radius. In particular, the Mbh-Mstar relation is mostly a consequence of the Mbh-sigma and sigma-Mstar relations, and is heavily biased by up to a factor of 50 at small masses. This helps resolve the discrepancy between dynamically-based black hole-galaxy scaling relations versus those of active galaxies. Our simulations also disfavour broad distributions of black hole masses at fixed sigma. Correcting for this bias suggests that the calibration factor used to estimate black hole masses in active galaxies should be reduced to values of fvir~1. Black hole mass densities should also be proportionally smaller, perhaps implying significantly higher radiative efficiencies/black hole spins. Reducing black hole masses also reduces the gravitational wave signal expected from black hole mergers.
Andreev reflections and the quantum physics of black holes
NASA Astrophysics Data System (ADS)
Manikandan, Sreenath K.; Jordan, Andrew N.
2017-12-01
We establish an analogy between superconductor-metal interfaces and the quantum physics of a black hole, using the proximity effect. We show that the metal-superconductor interface can be thought of as an event horizon and Andreev reflection from the interface is analogous to the Hawking radiation in black holes. We describe quantum information transfer in Andreev reflection with a final state projection model similar to the Horowitz-Maldacena model for black hole evaporation. We also propose the Andreev reflection analogue of Hayden and Preskill's description of a black hole final state, where the black hole is described as an information mirror. The analogy between crossed Andreev reflections and Einstein-Rosen bridges is discussed: our proposal gives a precise mechanism for the apparent loss of quantum information in a black hole by the process of nonlocal Andreev reflection, transferring the quantum information through a wormhole and into another universe. Given these established connections, we conjecture that the final quantum state of a black hole is exactly the same as the ground state wave function of the superconductor/superfluid in the Bardeen-Cooper-Schrieffer (BCS) theory of superconductivity; in particular, the infalling matter and the infalling Hawking quanta, described in the Horowitz-Maldacena model, forms a Cooper pairlike singlet state inside the black hole. A black hole evaporating and shrinking in size can be thought of as the analogue of Andreev reflection by a hole where the superconductor loses a Cooper pair. Our model does not suffer from the black hole information problem since Andreev reflection is unitary. We also relate the thermodynamic properties of a black hole to that of a superconductor, and propose an experiment which can demonstrate the negative specific heat feature of black holes in a growing/evaporating condensate.
Recent Increase in Black Carbon Concentrations from a Mt. Everest Ice Core Spanning 1860-2000 AD
NASA Astrophysics Data System (ADS)
Kaspari, S.; Schwikowski, M.; Gysel, M.; Mayewski, P. A.; Kang, S.; Hou, S.
2009-12-01
Black carbon produced by the incomplete combustion of biomass, coal and diesel fuels can significantly contribute to climate change by altering the Earth’s radiative balance. Black carbon in the atmosphere absorbs light and causes atmospheric heating, whereas black carbon deposited on snow and ice can significantly reduce the surface albedo, resulting in rapid melting of snow and ice. Historical records of black carbon concentration and distribution in the atmosphere are needed to determine the role of black carbon in climate change, however most studies have relied on estimated inventories based on wood and/or fossil fuel consumption data. Reconstructing black carbon concentrations in Asia is particularly important because this region has some of the largest black carbon sources globally, which negatively impact climate, water resources, agriculture and human health. We analyzed a Mt. Everest ice core for black carbon using a single particle soot photometer (SP2). The high-resolution black carbon data demonstrates strong seasonality, with peak concentrations during the winter-spring, and low concentrations during the summer monsoon season. Black carbon concentrations from 1975-2000 relative to 1860-1975 have increased approximately threefold, and the timing of this increase is consistent with black carbon emission inventory data from South Asia. It is notable that there is no increasing trend in iron (used as a proxy for dust) since 1860. This is significant because it suggests that if the recent retreat of glaciers in the region is due, at least in part, to the effect of impurities on snow albedo, the reduced albedo is due to changes in black carbon emissions, not dust.
2. BLACK RIVER CANAL SUPPLY FROM END OF MAIN ...
2. BLACK RIVER CANAL - SUPPLY FROM END OF MAIN CANAL TO BLACK RIVER. VIEW TO SOUTHWEST - Carlsbad Irrigation District, Black River Canal, 15 miles Southeast of Carlsbad near Malaga, Carlsbad, Eddy County, NM
ERIC Educational Resources Information Center
Byrd, Donald
1972-01-01
Discusses the definition of black music in terms of the history and cultural background of black people, places it within the larger scope of western music, and suggests its survival value with respect to black people. (JM)
Shaping Globular Clusters with Black Holes
NASA Astrophysics Data System (ADS)
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, single and binary star evolution, galactic tides, and multi-body encounters. From their grid of models with varying input parameters, the authors then determine which fit best to NGC 3201s final observational properties.Surface brightness profiles for all globular-cluster models at late times compared to observations of NGC 3201 (yellow circles). Blue lines represent models with few retained black holes; black lines represent models with many retained black holes. [Kremer et al. 2018]Retention MattersKremer and collaborators find that the models that best represent NGC 3201 all retain more than 200 black holes at the end of the simulation; models that lost too many black holes due to natal kicks did not match observations of NGC 3201 as well. The models with large numbers of retained black holes also harbored binaries just like the one recently detected in NGC 3201.Models that retain few black holes, on the other hand, may instead be good descriptions of so-called core-collapsed globular clusters observed in the Milky Way. The authors demonstrate that these clusters could contain black holes in binaries with stars known as blue stragglers, which may also be detectable with radial velocity techniques.Kremer and collaborators results suggest that globular clusters similar to NGC 3201 contain hundreds of invisible black holes waiting to be discovered, and they indicate some of the differences in cluster properties caused by hosting such a large population of black holes. We can hope that future observations and modeling will continue to illuminate the complicated relationship between globular clusters and the black holes that live in them.CitationKyle Kremer et al 2018 ApJL 855 L15. doi:10.3847/2041-8213/aab26c
NASA's Chandra Finds Black Holes Are "Green"
NASA Astrophysics Data System (ADS)
2006-04-01
Black holes are the most fuel efficient engines in the Universe, according to a new study using NASA's Chandra X-ray Observatory. By making the first direct estimate of how efficient or "green" black holes are, this work gives insight into how black holes generate energy and affect their environment. The new Chandra finding shows that most of the energy released by matter falling toward a supermassive black hole is in the form of high-energy jets traveling at near the speed of light away from the black hole. This is an important step in understanding how such jets can be launched from magnetized disks of gas near the event horizon of a black hole. Illustration of Fuel for a Black Hole Engine Illustration of Fuel for a Black Hole Engine "Just as with cars, it's critical to know the fuel efficiency of black holes," said lead author Steve Allen of the Kavli Institute for Particle Astrophysics and Cosmology at Stanford University, and the Stanford Linear Accelerator Center. "Without this information, we cannot figure out what is going on under the hood, so to speak, or what the engine can do." Allen and his team used Chandra to study nine supermassive black holes at the centers of elliptical galaxies. These black holes are relatively old and generate much less radiation than quasars, rapidly growing supermassive black holes seen in the early Universe. The surprise came when the Chandra results showed that these "quiet" black holes are all producing much more energy in jets of high-energy particles than in visible light or X-rays. These jets create huge bubbles, or cavities, in the hot gas in the galaxies. Animation of Black Hole in Elliptical Galaxy Animation of Black Hole in Elliptical Galaxy The efficiency of the black hole energy-production was calculated in two steps: first Chandra images of the inner regions of the galaxies were used to estimate how much fuel is available for the black hole; then Chandra images were used to estimate the power required to produce the cavities. "If a car was as fuel-efficient as these black holes, it could theoretically travel over a billion miles on a gallon of gas," said coauthor Christopher Reynolds of the University of Maryland, College Park. New details are given about how black hole engines achieve this extreme efficiency. Some of the gas first attracted to the black holes may be blown away by the energetic activity before it gets too near the black hole, but a significant fraction must eventually approach the event horizon where it is used with high efficiency to power the jets. The study also implies that matter flows towards the black holes at a steady rate for several million years. Chandra X-ray Images of Elliptical Galaxies Chandra X-ray Images of Elliptical Galaxies "These black holes are very efficient, but it also takes a very long time to refuel them," said Steve Allen who receives funding from the Office of Science of the Department of Energy. This new study shows that black holes are green in another important way. The energy transferred to the hot gas by the jets should keep hot gas from cooling, thereby preventing billions of new stars from forming. This will place limits on the growth of the largest galaxies, and prevent galactic sprawl from taking over the neighborhood. These results will appear in an upcoming issue of the Monthly Notices of the Royal Astronomical Society. NASA's Marshall Space Flight Center, Huntsville, Ala., manages the Chandra program for the agency's Science Mission Directorate. The Smithsonian Astrophysical Observatory controls science and flight operations from the Chandra X-ray Center, Cambridge, Mass. Additional information and images can be found at: http://chandra.harvard.edu and http://chandra.nasa.gov For information about NASA and agency programs on the Web, visit: http://www.nasa.gov
Simulations of high-spin black-hole binaries
NASA Astrophysics Data System (ADS)
Scheel, Mark; Lovelace, Geoffrey
2014-03-01
Black holes can in principle have spins up to the Kerr limit a = 1 , and some (highly uncertain) estimates from X-ray binaries yield a > 0 . 98 . Because binaries with highly-spinning black holes may be detectable by LIGO, it is important to be able to simulate and understand these systems. We present binary black hole simulations with large spins, including a generic, precessing simulation with a spin of a > 0 . 99 on one of the black holes. We discuss some of the difficulties with simulating high-spin black holes and how to overcome them.
Cosmic censorship of rotating Anti-de Sitter black hole
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gwak, Bogeun; Lee, Bum-Hoon, E-mail: rasenis@sogang.ac.kr, E-mail: bhl@sogang.ac.kr
2016-02-01
We test the validity of cosmic censorship in the rotating anti-de Sitter black hole. For this purpose, we investigate whether the extremal black hole can be overspun by the particle absorption. The particle absorption will change the mass and angular momentum of the black hole, which is analyzed using the Hamilton-Jacobi equations consistent with the laws of thermodynamics. We have found that the mass of the extremal black hole increases more than the angular momentum. Therefore, the outer horizon of the black hole still exists, and cosmic censorship is valid.
NASA Astrophysics Data System (ADS)
Shen, Q.; Gao, Q.; Yu, C.; Zhang, L.; Wang, Z.
2016-12-01
Water column hypoxia is one of the most serious threats from eutrophication to large water bodies. In the past several years, black bloom phenomenon has become a serious ecosystem disaster in some important severe eutrophic lakes in China, which caused not only environment degradation but also drinking water crisis. Black color and offensive odour of the water column are two notorious sensory features. High Fe2+ and ΣH2S (ΣS2-=S2-+HS-+H2S) were typical characteristics of the black bloom water. Analysis of the black substances of the black bloom water using X-ray photoelectron spectroscopy indicated that abundant FeS were included in these particulates. The black color of the black bloom water could be attributed to the formation of FeS in the anoxic/anaerobic water column. Field investigation and laboratory incubation experiment indicated that the formation of black bloom was closely related to the Fe2+ and ΣH2S in surface sediments. The Fe2+ concentration in surface sediment pore water was high and showed a release tendency from the sediment water interface to the overlying water during the formation of black bloom, while the similar trend was found in ΣH2S production at sediment water micro-interface. Both Fe2+ and ΣS2- affected by oxic and redox conditions, respectively, contributed to the formation of black bloom significantly. However, ΣS2- was found to be the limiting factor directly controlling the outbreak of black bloom. Analysis of microbioal community diversity demonstrated that sulfate reducing bacteria (SRB) were abundant in the surface sediment of black bloom, which strongly influenced the production and accumulation of ΣH2S and drove the formation of black bloom.
Stamler, Jeremiah; Brown, Ian J; Yap, Ivan K S; Chan, Queenie; Wijeyesekera, Anisha; Garcia-Perez, Isabel; Chadeau-Hyam, Marc; Ebbels, Timothy M D; De Iorio, Maria; Posma, Joram; Daviglus, Martha L; Carnethon, Mercedes; Holmes, Elaine; Nicholson, Jeremy K; Elliott, Paul
2013-12-01
Black compared with non-Hispanic white Americans have higher systolic and diastolic blood pressure and rates of prehypertension/hypertension. Reasons for these adverse findings remain obscure. Analyses here focused on relations of foods/nutrients/urinary metabolites and higher black blood pressure for 369 black compared with 1190 non-Hispanic white Americans aged 40 to 59 years from 8 population samples. Multiple linear regression, standardized data from four 24-hour dietary recalls per person, two 24-hour urine collections, and 8 blood pressure measurements were used to quantitate the role of foods, nutrients, and metabolites in higher black blood pressure. Compared with non-Hispanic white Americans, blacks' average systolic/diastolic pressure was higher by 4.7/3.4 mm Hg (men) and 9.0/4.8 mm Hg (women). Control for higher body mass index of black women reduced excess black systolic/diastolic pressure to 6.8/3.8 mm Hg. Lesser intake of vegetables, fruits, grains, vegetable protein, glutamic acid, starch, fiber, minerals, and potassium, and higher intake of processed meats, pork, eggs, and sugar-sweetened beverages, along with higher cholesterol and higher Na/K ratio, related to in higher black blood pressure. Control for 11 nutrient and 10 non-nutrient correlates reduced higher black systolic/diastolic pressure to 2.3/2.3 mm Hg (52% and 33% reduction in men) and to 5.3/2.8 mm Hg (21% and 27% reduction in women). Control for foods/urinary metabolites had little further influence on higher black blood pressure. Less favorable multiple nutrient intake by blacks than non-Hispanic white Americans accounted, at least in part, for higher black blood pressure. Improved dietary patterns can contribute to prevention/control of more adverse black blood pressure levels.
Immigration and the health of U.S. black adults: does country of origin matter?
Hamilton, Tod G; Hummer, Robert A
2011-11-01
Previous work suggests that regional variation in pre-migration exposure to racism and discrimination, measured by a region's racial composition, predicts differences in individual-level health among black immigrants to the United States. We exploit data on both region and country of birth for black immigrants in the United States and methodology that allows for the identification of arrival cohorts to test whether there are sending country differences in the health of black adults in the United States that support this proposition. While testing this hypothesis, we also document heterogeneity in health across arrival cohorts and by duration of U.S. residence among black immigrants. Using data on working-age immigrant and U.S.-born blacks taken from the 1996-2010 waves of the March Current Population Survey, we show that relative to U.S.-born black adults, black immigrants report significantly lower odds of fair/poor health. After controlling for relevant social and demographic characteristics, immigrants' cohort of arrival, and immigrants' duration in the United States, our models show only modest differences in health between African immigrants and black immigrants who migrate from the other major sending countries or regions. Results also show that African immigrants maintain their health advantage over U.S.-born black adults after more than 20 years in the United States. In contrast, black immigrants from the Caribbean who have been in the United States for more than 20 years appear to experience some downward health assimilation. In conclusion, after accounting for relevant factors, we find that there are only modest differences in black immigrant health across countries of origin. Black immigrants appear to be very highly selected in terms of good health, although there are some indications of negative health assimilation for black immigrants from the Caribbean. Copyright © 2011 Elsevier Ltd. All rights reserved.
Jung, Ji-Hye; Kim, Hyun-Sook
2013-10-01
Non-alcoholic fatty liver disease (NAFLD) is defined as excess of fat in the liver. We investigated the effects of black soybean on the cholesterol metabolism and insulin resistance of mice fed high cholesterol/fat diets. Mice were randomly allocated into four groups that were fed different diets: the normal cholesterol/fat diet; high cholesterol/fat diets (HCD); and HCD with 1%, and 4% black soybean powder (1B-HCD, and 4B-HCD). Liver total cholesterol and triglyceride concentrations were significantly lower in the black soybean-supplemented groups than that in the HCD group. PCR revealed significantly lower hepatic SREBP2 and HMG-CoA reductase mRNA levels of black soybean-supplemented mice. Real-time PCR revealed significantly higher hepatic ABCA1 mRNA level of black soybean-supplemented mice, which may increase cholesterol efflux. Liver bile acids concentration was significantly high in the 4B-HCD group. Black soybean stimulated secretion of adiponectin, activation of pAMPK, and eliminated free fatty acids in the liver. Black soybean supplementation decreased MDA and nitrate level. The activities of SOD, catalase, and GPx were restored by black soybean supplementation. Our data strongly indicate that black soybean influences the balance between oxidative and antioxidative stress. We suggest that black soybean improves cholesterol metabolism, insulin resistance, and alleviates oxidative damage in NAFLD. Published by Elsevier Ltd.
Kucbel, Marek; Corsaro, Agnieszka; Švédová, Barbora; Raclavská, Helena; Raclavský, Konstantin; Juchelková, Dagmar
2017-12-01
Black carbon - a primary component of particulate matter emitted from an incomplete combustion of fossil fuels, biomass, and biofuels - has been found to have a detrimental effect on human health and the environment. Since black carbon emissions data are not readily available, no measures are implemented to reduce black carbon emissions. The temporal and seasonal variations of black carbon concentrations were evaluated during 2012-2014. The data were collected in the highly polluted European city - Ostrava, Czech Republic, surrounded by major highways and large industries. Significantly higher black carbon concentrations were obtained in Ostrava, relative to other European cities and the magnitude was equivalent to the magnitude of black carbon concentrations measured in Poland and China. The data were categorized to heating and non-heating seasons based on the periodic pattern of daily and monthly average concentrations of black carbon. A higher black carbon concentration was obtained during heating season than non-heating season and was primarily associated with an increase in residential coal burning and meteorological parameters. The concentration of black carbon was found to be negatively correlated with temperature and wind speed, and positively correlated with the relative humidity. Other black carbon sources potentially included emissions from vehicle exhaust and the local steel-producing industry. Copyright © 2017 Elsevier Ltd. All rights reserved.
Martino, Suella; Jamme, Mathieu; Deligny, Christophe; Busson, Marc; Loiseau, Pascale; Azoulay, Elie; Galicier, Lionel; Pène, Frédéric; Provôt, François; Dossier, Antoine; Saheb, Samir; Veyradier, Agnès; Coppo, Paul
2016-01-01
Black people are at increased risk of thrombotic thrombocytopenic purpura (TTP). Whether clinical presentation of TTP in Black patients has specific features is unknown. We assessed here differences in TTP presentation and outcome between Black and White patients. Clinical presentation was comparable between both ethnic groups. However, prognosis differed with a lower death rate in Black patients than in White patients (2.7% versus 11.6%, respectively, P = .04). Ethnicity, increasing age and neurologic involvement were retained as risk factors for death in a multivariable model (P < .05 all). Sixty-day overall survival estimated by the Kaplan-Meier curves and compared with the Log-Rank test confirmed that Black patients had a better survival than White patients (P = .03). Salvage therapies were similarly performed between both groups, suggesting that disease severity was comparable. The comparison of HLA-DRB1*11, -DRB1*04 and -DQB1*03 allele frequencies between Black patients and healthy Black individuals revealed no significant difference. However, the protective allele against TTP, HLA-DRB1*04, was dramatically decreased in Black individuals in comparison with White individuals. Black people with TTP may have a better survival than White patients despite a comparable disease severity. A low natural frequency of HLA-DRB1*04 in Black ethnicity may account for the greater risk of TTP in this population.
Martino, Suella; Jamme, Mathieu; Deligny, Christophe; Busson, Marc; Loiseau, Pascale; Azoulay, Elie; Galicier, Lionel; Pène, Frédéric; Provôt, François; Dossier, Antoine; Saheb, Samir; Veyradier, Agnès; Coppo, Paul
2016-01-01
Black people are at increased risk of thrombotic thrombocytopenic purpura (TTP). Whether clinical presentation of TTP in Black patients has specific features is unknown. We assessed here differences in TTP presentation and outcome between Black and White patients. Clinical presentation was comparable between both ethnic groups. However, prognosis differed with a lower death rate in Black patients than in White patients (2.7% versus 11.6%, respectively, P = .04). Ethnicity, increasing age and neurologic involvement were retained as risk factors for death in a multivariable model (P < .05 all). Sixty-day overall survival estimated by the Kaplan-Meier curves and compared with the Log-Rank test confirmed that Black patients had a better survival than White patients (P = .03). Salvage therapies were similarly performed between both groups, suggesting that disease severity was comparable. The comparison of HLA-DRB1*11, -DRB1*04 and -DQB1*03 allele frequencies between Black patients and healthy Black individuals revealed no significant difference. However, the protective allele against TTP, HLA-DRB1*04, was dramatically decreased in Black individuals in comparison with White individuals. Black people with TTP may have a better survival than White patients despite a comparable disease severity. A low natural frequency of HLA-DRB1*04 in Black ethnicity may account for the greater risk of TTP in this population. PMID:27383202
Stereotype threat and racial differences in citizens' experiences of police encounters.
Najdowski, Cynthia J; Bottoms, Bette L; Goff, Phillip Atiba
2015-10-01
We conducted 2 studies to investigate how cultural stereotypes that depict Blacks as criminals affect the way Blacks experience encounters with police officers, expecting that such encounters induce Blacks to feel stereotype threat (i.e., concern about being judged and treated unfairly by police because of the stereotype). In Study 1, we asked Black and White participants to report how they feel when interacting with police officers in general. As predicted, Blacks, but not Whites, reported concern that police officers stereotype them as criminals simply because of their race. In addition, this effect was found for Black men but not Black women. In Study 2, we asked Black and White men to imagine a specific police encounter and assessed potential downstream consequences of stereotype threat. Consistent with Study 1, Black but not White men anticipated feeling stereotype threat in the hypothetical police encounter. Further, racial differences in anticipated threat translated into racial differences in anticipated anxiety, self-regulatory efforts, and behavior that is commonly perceived as suspicious by police officers. By demonstrating that Blacks might expect to be judged and treated unfairly by police because of the negative stereotype of Black criminality, this research extends stereotype threat theory to the new domain of criminal justice encounters. It also has practical implications for understanding how the stereotype could ironically contribute to bias-based policing and racial disparities in the justice system. (c) 2015 APA, all rights reserved).
Regimes of mini black hole abandoned to accretion
NASA Astrophysics Data System (ADS)
Paik, Biplab
2018-01-01
Being inspired by the Eddington’s idea, along with other auxiliary arguments, it is unveiled that there exist regimes of a black hole that would prohibit accretion of ordinary energy. In explicit words, there exists a lower bound to black hole mass below which matter accretion process does not run for black holes. Not merely the baryonic matter, but, in regimes, also the massless photons could get prohibited from rushing into a black hole. However, unlike the baryon accretion abandoned black hole regime, the mass-regime of a black hole prohibiting accretion of radiation could vary along with its ambient temperature. For example, we discuss that earlier to 10‑8 s after the big-bang, as the cosmological temperature of the Universe grew above ˜ 1014 K, the mass range of black hole designating the radiation accretion abandoned regime, had to be in varying state being connected with the instantaneous age of the evolving Universe by an “one half” power law. It happens to be a fact that a black hole holding regimes prohibiting accretion of energy is gigantic by its size in comparison to the Planck length-scale. Hence the emergence of these regimes demands mini black holes for not being viable as profound suckers of energy. Consideration of accretion abandoned regimes could be crucial for constraining or judging the evolution of primordial black holes over the age of the Universe.
Supermassive black holes do not correlate with galaxy disks or pseudobulges.
Kormendy, John; Bender, R; Cornell, M E
2011-01-20
The masses of supermassive black holes are known to correlate with the properties of the bulge components of their host galaxies. In contrast, they seem not to correlate with galaxy disks. Disk-grown 'pseudobulges' are intermediate in properties between bulges and disks; it has been unclear whether they do or do not correlate with black holes in the same way that bulges do. At stake in this issue are conclusions about which parts of galaxies coevolve with black holes, possibly by being regulated by energy feedback from black holes. Here we report pseudobulge classifications for galaxies with dynamically detected black holes and combine them with recent measurements of velocity dispersions in the biggest bulgeless galaxies. These data confirm that black holes do not correlate with disks and show that they correlate little or not at all with pseudobulges. We suggest that there are two different modes of black-hole feeding. Black holes in bulges grow rapidly to high masses when mergers drive gas infall that feeds quasar-like events. In contrast, small black holes in bulgeless galaxies and in galaxies with pseudobulges grow as low-level Seyfert galaxies. Growth of the former is driven by global processes, so the biggest black holes coevolve with bulges, but growth of the latter is driven locally and stochastically, and they do not coevolve with disks and pseudobulges.
Regular black holes: Electrically charged solutions, Reissner-Nordstroem outside a de Sitter core
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lemos, Jose P. S.; Zanchin, Vilson T.; Centro de Ciencias Naturais e Humanas, Universidade Federal do ABC, Rua Santa Adelia, 166, 09210-170, Santo Andre, Sao Paulo
2011-06-15
To have the correct picture of a black hole as a whole, it is of crucial importance to understand its interior. The singularities that lurk inside the horizon of the usual Kerr-Newman family of black hole solutions signal an endpoint to the physical laws and, as such, should be substituted in one way or another. A proposal that has been around for sometime is to replace the singular region of the spacetime by a region containing some form of matter or false vacuum configuration that can also cohabit with the black hole interior. Black holes without singularities are called regularmore » black holes. In the present work, regular black hole solutions are found within general relativity coupled to Maxwell's electromagnetism and charged matter. We show that there are objects which correspond to regular charged black holes, whose interior region is de Sitter, whose exterior region is Reissner-Nordstroem, and the boundary between both regions is made of an electrically charged spherically symmetric coat. There are several types of solutions: regular nonextremal black holes with a null matter boundary, regular nonextremal black holes with a timelike matter boundary, regular extremal black holes with a timelike matter boundary, and regular overcharged stars with a timelike matter boundary. The main physical and geometrical properties of such charged regular solutions are analyzed.« less
Community Involvement in Recruiting Adoptive Homes for Black Children
ERIC Educational Resources Information Center
Washington, Valora
1987-01-01
Describes and assesses the impact of the Friends of Black Children project which enlists the aid of local communities and public adoption agencies to further the adoption of black children by black families. (Author/NH)
New entropy formula for Kerr black holes
NASA Astrophysics Data System (ADS)
González, Hernán A.; Grumiller, Daniel; Merbis, Wout; Wutte, Raphaela
2018-01-01
We introduce a new entropy formula for Kerr black holes inspired by recent results for 3-dimensional black holes and cosmologies with soft Heisenberg hair. We show that also Kerr-Taub-NUT black holes obey the same formula.
Black Perceptions of the Mayor: An Empirical Test.
ERIC Educational Resources Information Center
Foster, Lorn S.
1978-01-01
During the past ten years Blacks have increased their participation in the urban political process. In a few urban areas, such as Newark and Detroit, Blacks constitute an electoral majority and have elected Black mayors. (Author/RLV)
Black Carbon Diesel Initiative in the Russian Arctic
Mobile and stationary diesel engines are among the largest sources of black carbon emissions in the Arctic. To address this challenge, EPA is leading the Black Carbon Diesel Initiative under the Arctic Black Carbon Initiative (ABCI).
Chatters, Linda M.; Taylor, Robert Joseph; Bullard, Kai McKeever; Jackson, James S.
2010-01-01
This study examined differences in religious participation and spirituality among African Americans, Caribbean Blacks (Black Caribbeans) and non-Hispanic Whites. Data are taken from the National Survey of American Life, a nationally representative study of African Americans, Black Caribbeans and non-Hispanic Whites. Selected measures of organizational, nonorganizational and subjective religious participation were examined. African American and Caribbean Blacks were largely similar in their reports of religious involvement; both groups generally indicated higher levels of religious participation than non-Hispanic Whites. African Americans were more likely than Black Caribbeans to be official members of their places of worship, engage in activities (choirs, church clubs) at their place of worship and request prayer from others. Black Caribbeans reported reading religious materials more frequently than African Americans. The discussion notes the importance of examining ethnic differences within the black American population of the United States. PMID:20975850
Thermodynamics and phase transition of charged AdS black holes with a global monopole
NASA Astrophysics Data System (ADS)
Deng, Gao-Ming; Fan, Jinbo; Li, Xinfei; Huang, Yong-Chang
2018-01-01
Thermodynamical properties of charged AdS black holes with a global monopole still remain obscure. In this paper, we investigate the thermodynamics and phase transition of the black holes in the extended phase space. It is shown that thermodynamical quantities of the black holes exhibit an interesting dependence on the internal global monopole, and they perfectly satisfy both the first law of thermodynamics and Smarr relation. Furthermore, analysis of the local and the global thermodynamical stability manifests that the charged AdS black hole undergoes an elegant phase transition at critical point. Of special interest, critical behaviors of the black holes resemble a Van der Waals liquid-gas system. Our results not only reveal the effect of a global monopole on thermodynamics of AdS black holes, but also further support that Van der Waals-like behavior of the black holes is a universal phenomenon.
Phase transition of charged-AdS black holes and quasinormal modes: A time domain analysis
NASA Astrophysics Data System (ADS)
Chabab, M.; El Moumni, H.; Iraoui, S.; Masmar, K.
2017-10-01
In this work, we investigate the time evolution of a massless scalar perturbation around small and large RN-AdS4 black holes for the purpose of probing the thermodynamic phase transition. We show that below the critical point the scalar perturbation decays faster with increasing of the black hole size, both for small and large black hole phases. Our analysis of the time profile of quasinormal mode reveals a sharp distinction between the behaviors of both phases, providing a reliable tool to probe the black hole phase transition. However at the critical point P=Pc, as the black hole size extends, we note that the damping time increases and the perturbation decays faster, the oscillation frequencies raise either in small and large black hole phase. In this case the time evolution approach fails to track the AdS4 black hole phase.
Blue Thursday? Homicide and suicide among urban 15-24-year-old black male Americans.
Greenberg, M; Schneider, D
1992-01-01
A comparative analysis was made of day of the week variations in homicide and suicide deaths among 15-24-year-old white males, black males, white females, and black females in the 22 counties with the most black persons in the United States. Thirty-seven percent of black Americans and 14 percent of white Americans lived in these densely populated counties. The authors expected a weekend excess of homicide and a Monday excess of suicide. They found a pronounced excess of homicides on weekends, especially among white males. A slight excess of suicide was observed on Monday, but other slight excesses of suicide were also found. Young black males exhibited an unexpected excess of homicides and suicides on Thursday. On Thursdays the black male-white male ratio for homicide was 1.43 and for suicide, 1.26. Possible explanations for the young black males' blue Thursday phenomenon are offered. PMID:1594735
NASA Astrophysics Data System (ADS)
Toshmatov, Bobir; Stuchlík, Zdeněk; Schee, Jan; Ahmedov, Bobomurat
2018-04-01
The electromagnetic (EM) perturbations of the black hole solutions in general relativity coupled to nonlinear electrodynamics (NED) are studied for both electrically and magnetically charged black holes, assuming that the EM perturbations do not alter the spacetime geometry. It is shown that the effective potentials of the electrically and magnetically charged black holes related to test perturbative NED EM fields are related to the effective metric governing the photon motion, contrary to the effective potential of the linear electrodynamic (Maxwell) field that is related to the spacetime metric. Consequently, corresponding quasinormal (QN) frequencies differ as well. As a special case, we study new family of the NED black hole solutions which tend in the weak field limit to the Maxwell field, giving the Reissner-Nordström (RN) black hole solution. We compare the NED Maxwellian black hole QN spectra with the RN black hole QN spectra.
Effects of display characteristics and individual differences on preferences of VDT icon design.
Shieh, Kong-King; Ko, Ya-Hsien
2005-04-01
This study explored the effects of display characteristics such as target/background color combination, single/simultaneous presentation, and individual differences by sex, and design specialty on preferences of VDT icon design. The results indicated black targets (black-on-white, black-on-yellow) and black backgrounds (red-on-black, yellow-on-black) were the most popular and white targets (white-on-red, white-on-black) and white backgrounds (blue-on-white, red-on-white) were the second most popular. As for the chromatic color combinations, yellow-on-blue was the most favored. Subjects rated color combinations under single presentation higher than those under simultaneous presentation. Women rated purplish targets and rated purplish and blue backgrounds higher than men. Subjects with design background favored black more either as a target or background, but they favored turquoise less than those without design background.
Black start research of the wind and storage system based on the dual master-slave control
NASA Astrophysics Data System (ADS)
Leng, Xue; Shen, Li; Hu, Tian; Liu, Li
2018-02-01
Black start is the key to solving the problem of large-scale power failure, while the introduction of new renewable clean energy as a black start power supply was a new hotspot. Based on the dual master-slave control strategy, the wind and storage system was taken as the black start reliable power, energy storage and wind combined to ensure the stability of the micorgrid systems, to realize the black start. In order to obtain the capacity ratio of the storage in the small system based on the dual master-slave control strategy, and the black start constraint condition of the wind and storage combined system, obtain the key points of black start of wind storage combined system, but also provide reference and guidance for the subsequent large-scale wind and storage combined system in black start projects.
Black churches and HIV/AIDS: factors influencing congregations’ responsiveness to social issues.
Fulton, Brad R
2011-01-01
The ambivalent response of many black churches to current social issues has caused some scholars to question the centrality of black churches within African-American communities. Using a nationally representative sample of black congregations, this study engages the debate about the institutional centrality of black churches by focusing on their response to HIV/AIDS. Although many congregational studies treat black churches as a monolithic whole, this analysis identifies heterogeneity among black churches that shapes their responsiveness to social issues. Contrary to prior claims, a congregation's liberal-conservative ideological orientation does not significantly affect its likelihood of having an HIV/AIDS program. Beyond assessing churches’ internal characteristics, this study uses institutional theory to analyze churches as open systems that can be influenced by their surrounding environment. It demonstrates that externally engaged congregations are significantly more likely to have a program. These results indicate that black churches maintain institutional centrality by engaging their external environment.
Black Lives Matter: A Call to Action for Counseling Psychology Leaders.
Crowell, Candice; Mosley, Della; Falconer, Jameca; Faloughi, Reuben; Singh, Anneliese; Stevens-Watkins, Danelle; Cokley, Kevin
2017-08-01
Police brutality and widespread systemic racism represent historical and current sources of trauma in Black communities. Both the Black Lives Matter movement and counseling psychology propose to confront these realities at multiple levels. Black Lives Matter seeks to increase awareness about systemic racism and promote resilience among Black people. Counseling psychology states values of multiculturalism, social justice, and advocacy. Executive leadership in counseling psychology may seek to promote racial justice, yet struggle with how to participate in Black Lives Matter movements and address racial discrimination within larger systems spontaneously and consistently. However, counseling psychology trainees and professionals are actively involved in the Black Lives Matter movement, leading the way forward. Through the framework of spontaneity in social movements, this manuscript highlights what counseling psychologists are currently contributing to Black Lives Matter and makes recommendations that build on the opportunity counseling psychologists have for further involvement in the movement.
Femtosecond laser fabricating black silicon in alkaline solution
NASA Astrophysics Data System (ADS)
Meng, Jiao; Song, Haiying; Li, Xiaoli; Liu, Shibing
2015-03-01
An efficient approach for enhancing the surface antireflection is proposed, in which a black silicon is fabricated by a femtosecond laser in alkaline solution. In the experiment, 2 wt% NaOH solution is formulated at room temperature (22 ± 1 °C). Then, a polished silicon is scanned via femtosecond laser irradiation in 2 wt% NaOH solution. Jungle-like microstructures on the black silicon surface are characterized using an atomic force microscopy. The reflectance of the black silicon is measured at the wavelengths ranging from 400 to 750 nm. Compared to the polished silicon, the black silicon can significantly suppress the optical reflection throughout the visible region (<5 %). Meanwhile, we also investigated the factors of the black silicon, including the femtosecond laser pulse energy and the scanning speed. This method is simple and effective to acquire the black silicon, which probably has a large advantage in fast and cost-effective black silicon fabrication.
NASA Astrophysics Data System (ADS)
Gupta, Anshu; Krishnan, Badri; Nielsen, Alex B.; Schnetter, Erik
2018-04-01
The behavior of quasilocal black hole horizons in a binary black hole merger is studied numerically. We compute the horizon multipole moments, fluxes, and other quantities on black hole horizons throughout the merger. These lead to a better qualitative and quantitative understanding of the coalescence of two black holes: how the final black hole is formed, initially grows, and then settles down to a Kerr black hole. We calculate the rate at which the final black hole approaches equilibrium in a fully nonperturbative situation and identify a time at which the linear ringdown phase begins. Finally, we provide additional support for the conjecture that fields at the horizon are correlated with fields in the wave zone by comparing the in-falling gravitational wave flux at the horizon to the outgoing flux as estimated from the gravitational waveform.
Insight into the microscopic structure of an AdS black hole from a thermodynamical phase transition.
Wei, Shao-Wen; Liu, Yu-Xiao
2015-09-11
Comparing with an ordinary thermodynamic system, we investigate the possible microscopic structure of a charged anti-de Sitter black hole completely from the thermodynamic viewpoint. The number density of the black hole molecules is introduced to measure the microscopic degrees of freedom of the black hole. We found that the number density suffers a sudden change accompanied by a latent heat when the black hole system crosses the small-large black hole coexistence curve, while when the system passes the critical point, it encounters a second-order phase transition with a vanishing latent heat due to the continuous change of the number density. Moreover, the thermodynamic scalar curvature suggests that there is a weak attractive interaction between two black hole molecules. These phenomena might cast new insight into the underlying microscopic structure of a charged anti-de Sitter black hole.
ERIC Educational Resources Information Center
Nober, E. Harris; Seymour, Harry N.
In order to investigate the possible consequences of dialectical differences in the classroom setting relative to the low income black and white first grade child and the prospective white middle-class teacher, 25 black and 25 white university listeners yielded speech recognition scores for 48 black and 48 white five-year-old urban school-children…
33 CFR 207.590 - Black Rock Canal and Lock at Buffalo, N.Y.; use, administration, and navigation.
Code of Federal Regulations, 2013 CFR
2013-07-01
... 33 Navigation and Navigable Waters 3 2013-07-01 2013-07-01 false Black Rock Canal and Lock at... Black Rock Canal and Lock at Buffalo, N.Y.; use, administration, and navigation. (a) The term “canal” when used in this section will mean all of the Black Rock Waterway, including Black Rock Lock, and all...
33 CFR 207.590 - Black Rock Canal and Lock at Buffalo, N.Y.; use, administration, and navigation.
Code of Federal Regulations, 2011 CFR
2011-07-01
... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Black Rock Canal and Lock at... Black Rock Canal and Lock at Buffalo, N.Y.; use, administration, and navigation. (a) The term “canal” when used in this section will mean all of the Black Rock Waterway, including Black Rock Lock, and all...
33 CFR 207.590 - Black Rock Canal and Lock at Buffalo, N.Y.; use, administration, and navigation.
Code of Federal Regulations, 2012 CFR
2012-07-01
... 33 Navigation and Navigable Waters 3 2012-07-01 2012-07-01 false Black Rock Canal and Lock at... Black Rock Canal and Lock at Buffalo, N.Y.; use, administration, and navigation. (a) The term “canal” when used in this section will mean all of the Black Rock Waterway, including Black Rock Lock, and all...
33 CFR 207.590 - Black Rock Canal and Lock at Buffalo, N.Y.; use, administration, and navigation.
Code of Federal Regulations, 2014 CFR
2014-07-01
... 33 Navigation and Navigable Waters 3 2014-07-01 2014-07-01 false Black Rock Canal and Lock at... Black Rock Canal and Lock at Buffalo, N.Y.; use, administration, and navigation. (a) The term “canal” when used in this section will mean all of the Black Rock Waterway, including Black Rock Lock, and all...
ERIC Educational Resources Information Center
Cohen, Rodney T.
2006-01-01
Historically, Historically Black Colleges and Universities (HBCUs) have struggled in their attempt to solicit financial gifts from its alumni. Traditionally, black college alumni have appeared to show negligence in their effort to support their alma maters. As a result, many black colleges have ignored them as potential donors. This lack of…
ERIC Educational Resources Information Center
Journal of Blacks in Higher Education, 2003
2003-01-01
Nationwide, fewer than two out of five entering black college students earn their degrees, while three out of five entering white students go on to graduate. Nearly 19 out of 20 black students at highly competitive universities earn their diplomas. Black women outpace black men in college completion. Examines trends in black graduation rates at…
Einstein's Gift: Stellar Mass Black Holes in the LIGO Era
NASA Astrophysics Data System (ADS)
Cadonati, Laura; Georgia Institute of Technology, LIGO-Virgo Collaboration
2017-01-01
The discovery of gravitational waves from the coalescence of black hole binary systems in LIGO has provided the first evidence for heavy stellar mass black holes. In this talk, I will review the observational evidence for black holes in LIGO data, its astrophysical implications and the plans for the near and long term future of ground based gravitational wave detection of black hole binary coalescences.
77 FR 73025 - Procurement List; Proposed Additions and Deletions
Federal Register 2010, 2011, 2012, 2013, 2014
2012-12-07
... Administration. Group 1 and 2 Spices NSN: 8950-01-E60-7765--Black Pepper, Ground Gourmet, 1.5 oz NSN: 8950-01-E60-7766--Black Pepper, Ground, Gourment, 16 oz, can NSN: 8950-01-E60-7767--Black Pepper, Ground, Gourmet, 16 oz NSN: 8950-01-E60-7768--Black Pepper, Ground, Gourment, 18 oz, can NSN: 8950-01-E60-7769--Black...
ERIC Educational Resources Information Center
Rumble, Merle B.
2013-01-01
This study examined how the use of African American literature that depicts Black males influences the reading comprehension and the reading motivation of Black boys as demonstrated through oral, written, and creative expressions. Studies have been conducted using children's literature with Black boys to examine their social interaction with the…
ERIC Educational Resources Information Center
Pabon, Amber Jean-Marie
2017-01-01
This article draws from data in a larger qualitative study on the lives of black male teachers in US public urban schools. I examine their schooling experiences as black male youth. By coupling theories of social suffering with life history methodology, this research analyzes how three black male teachers experienced frustration, marginalization,…
The Effect of Race in Patients with Achalasia Diagnosed With High-Resolution Esophageal Manometry.
Chedid, Victor; Rosenblatt, Elizabeth; Gandhi, Kunjal Komal; Dhalla, Sameer; Nandwani, Monica C; Stein, Ellen M; Clarke, John O
2018-02-01
The advent of the Chicago Classification for esophageal motility disorders allowed for clinically reproducible subgrouping of patients with achalasia based on manometric phenotype. However, there are limited data with regards to racial variation using high-resolution esophageal manometry (HREM). The aim of our study was to evaluate the racial differences in patients with achalasia diagnosed with HREM using the Chicago Classification. We evaluated the clinical presentation, treatment decisions and outcomes between blacks and non-blacks with achalasia to identify potential racial disparities. We performed a retrospective review of consecutive patients referred for HREM at a single tertiary referral center from June 2008 through October 2012. All patients diagnosed with achalasia on HREM according to the Chicago Classification were included. Demographic, clinical and manometric data were abstracted. All studies interpreted before the Chicago Classification was in widespread use were reanalyzed. Race was defined as black or non-black. Patients who had missing data were excluded. Proportions were compared using chi-squared analysis and means were compared using the Student's t-test. A total of 1,268 patients underwent HREM during the study period, and 105 (8.3%) were manometrically diagnosed with achalasia (53% female, mean age: 53.8 ± 17.0 years) and also met the aforementioned inclusion and exclusion criteria. A higher percentage of women presented with achalasia in blacks as compared to whites or other races (P < 0.001). Non-blacks were more likely to present with reflux than blacks (P = 0.01), while blacks were more likely to be treated on the inpatient service than non-blacks (P < 0.001). There were no other significant differences noted in clinical presentation, treatment decisions and treatment outcomes among blacks and non-blacks. Our study highlights possible racial differences between blacks and non-blacks, including a higher proportion of black women diagnosed with achalasia and most blacks presenting with dysphagia. There is possibly a meaningful interaction of race and sex in the development of achalasia that might represent genetic differences in its pathophysiology. Further prospective studies are required to identify such differences. Copyright © 2018 Southern Society for Clinical Investigation. Published by Elsevier Inc. All rights reserved.
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.
Asha, Srinivasan; Sreekumar, Sweda; Soniya, E V
2016-01-01
Analysis of high-throughput small RNA deep sequencing data, in combination with black pepper transcriptome sequences revealed microRNA-mediated gene regulation in black pepper ( Piper nigrum L.). Black pepper is an important spice crop and its berries are used worldwide as a natural food additive that contributes unique flavour to foods. In the present study to characterize microRNAs from black pepper, we generated a small RNA library from black pepper leaf and sequenced it by Illumina high-throughput sequencing technology. MicroRNAs belonging to a total of 303 conserved miRNA families were identified from the sRNAome data. Subsequent analysis from recently sequenced black pepper transcriptome confirmed precursor sequences of 50 conserved miRNAs and four potential novel miRNA candidates. Stem-loop qRT-PCR experiments demonstrated differential expression of eight conserved miRNAs in black pepper. Computational analysis of targets of the miRNAs showed 223 potential black pepper unigene targets that encode diverse transcription factors and enzymes involved in plant development, disease resistance, metabolic and signalling pathways. RLM-RACE experiments further mapped miRNA-mediated cleavage at five of the mRNA targets. In addition, miRNA isoforms corresponding to 18 miRNA families were also identified from black pepper. This study presents the first large-scale identification of microRNAs from black pepper and provides the foundation for the future studies of miRNA-mediated gene regulation of stress responses and diverse metabolic processes in black pepper.
The angry black woman: the impact of pejorative stereotypes on psychotherapy with black women.
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.
Racial residential segregation, socioeconomic disparities, and the White-Black survival gap.
Popescu, Ioana; Duffy, Erin; Mendelsohn, Joshua; Escarce, José J
2018-01-01
To evaluate the association between racial residential segregation, a prominent manifestation of systemic racism, and the White-Black survival gap in a contemporary cohort of adults, and to assess the extent to which socioeconomic inequality explains this association. This was a cross sectional study of White and Black men and women aged 35-75 living in 102 large US Core Based Statistical Areas. The main outcome was the White-Black survival gap. We used 2009-2013 CDC mortality data for Black and White men and women to calculate age-, sex- and race adjusted White and Black mortality rates. We measured segregation using the Dissimilarity index, obtained from the Manhattan Institute. We used the 2009-2013 American Community Survey to define indicators of socioeconomic inequality. We estimated the CBSA-level White-Black gap in probability of survival using sequential linear regression models accounting for the CBSA dissimilarity index and race-specific socioeconomic indicators. Black men and women had a 14% and 9% lower probability of survival from age 35 to 75 than their white counterparts. Residential segregation was strongly associated with the survival gap, and this relationship was partly, but not fully, explained by socioeconomic inequality. At the lowest observed level of segregation, and with the Black socioeconomic status (SES) assumed to be at the White SES level scenario, the survival gap is essentially eliminated. White-Black differences in survival remain wide notwithstanding public health efforts to improve life expectancy and initiatives to reduce health disparities. Eliminating racial residential segregation and bringing Black socioeconomic status (SES) to White SES levels would eliminate the White-Black survival gap.
Boosting jet power in black hole spacetimes
Neilsen, David; Lehner, Luis; Palenzuela, Carlos; Hirschmann, Eric W.; Liebling, Steven L.; Motl, Patrick M.; Garrett, Travis
2011-01-01
The extraction of rotational energy from a spinning black hole via the Blandford–Znajek mechanism has long been understood as an important component in models to explain energetic jets from compact astrophysical sources. Here we show more generally that the kinetic energy of the black hole, both rotational and translational, can be tapped, thereby producing even more luminous jets powered by the interaction of the black hole with its surrounding plasma. We study the resulting Poynting jet that arises from single boosted black holes and binary black hole systems. In the latter case, we find that increasing the orbital angular momenta of the system and/or the spins of the individual black holes results in an enhanced Poynting flux. PMID:21768341
Black Holes in the Cosmos, the Lab, and in Fundamental Physics (1/3)
Giddings, Steve
2018-02-02
Black holes present the extreme limits of physics. They are ubiquitous in the cosmos, and in some extra-dimensional scenarios they could be produced at colliders. They have also yielded a puzzle that challenges the foundations of physics. These talks will begin with an overview of the basics of black hole physics, and then briefly summarize some of the exciting developments with cosmic black holes. They will then turn to properties of quantum black holes, and the question of black hole production in high energy collisions, perhaps beginning with the LHC. I will then overview the apparent paradox emerging from Hawking's discovery of black hole evaporation, and what it could be teaching us about the foundations of quantum mechanics and gravity.
Characterization of volatile aroma compounds from red and black rice bran.
Sukhonthara, Sukhontha; Theerakulkait, Chockchai; Miyazawa, Mitsuo
2009-01-01
The volatile oils from red and black rice bran were obtained by hydrodistillation using diethyl ester and the components of that oil were analyzed by capillary GC-MS. The volatile components of essential oil from red and black rice bran were analyzed by GC and GC-MS. One hundred twenty-nine (129) of volatile compounds were identified in red and black rice bran. Myristic acid, nonanal, (E)-beta-ocimene and 6, 10, 14-trimethyl-2-pentadecanone were main compounds in red rice bran, whereas myristic acid, nonanal, caproic acid, pentadecanal and pelargonic acid were main compounds in black rice bran. Guaiacol, presented at 0.81 mg/100 g in black rice bran, is responsible for the characteristic component in black rice.
Black Holes in the Cosmos, the Lab, and in Fundamental Physics (3/3)
Giddings, Steve
2018-05-23
Black holes present the extreme limits of physics. They are ubiquitous in the cosmos, and in some extra-dimensional scenarios they could be produced at colliders. They have also yielded a puzzle that challenges the foundations of physics. These talks will begin with an overview of the basics of black hole physics, and then briefly summarize some of the exciting developments with cosmic black holes. They will then turn to properties of quantum black holes, and the question of black hole production in high energy collisions, perhaps beginning with the LHC. I will then overview the apparent paradox emerging from Hawking's discovery of black hole evaporation, and what it could be teaching us about the foundations of quantum mechanics and gravity.
The Black Holes in the Hearts of Galaxies
NASA Technical Reports Server (NTRS)
Rigby, Jane
2010-01-01
In the past 20 years, astronomers have discovered that almost every galaxy contains a black hole at its center. These black holes outweigh our sun by a factor of a million to a billion. Surprisingly, there's a very tight connection between the size of the galaxy and its central black hole -- the bigger the galaxy, the bigger the black hole. We don't know why this relationship exists -- how can a black hole, with a sphere of influence the size of our solar system, know what kind of galaxy it inhabits? What processes create this relationship? I'll explore these topics, and show how new space telescopes are helping us discover thousands of black holes and explore how they evolve with time.
Posttraumatic stress disorder among black Vietnam veterans.
Allen, I M
1986-01-01
Because of racism in the military and racial and social upheaval in the United States during the Vietnam War years, as well as limited opportunities for blacks in the postwar period, black veterans of the Vietnam War often harbor conflicting feelings about their wartime experiences and have difficulty rationalizing brutality against the Vietnamese. As a result, black veterans suffer from posttraumatic stress disorder (PTSD) at a higher rate than white veterans. Diagnosis and treatment of PTSD in black veterans is complicated by the tendency to misdiagnose black patients, by the varied manifestations of PTSD, and by patients' frequent alcohol and drug abuse and medical, legal, personality, and vocational problems. The author presents his and others' recommendations about ways to treat black veterans with PTSD.
Black Holes in the Cosmos, the Lab, and in Fundamental Physics (2/3)
Giddings, Steven
2018-02-09
Black holes present the extreme limits of physics. They are ubiquitous in the cosmos, and in some extra-dimensional scenarios they could be produced at colliders. They have also yielded a puzzle that challenges the foundations of physics. These talks will begin with an overview of the basics of black hole physics, and then briefly summarize some of the exciting developments with cosmic black holes. They will then turn to properties of quantum black holes, and the question of black hole production in high energy collisions, perhaps beginning with the LHC. I will then overview the apparent paradox emerging from Hawking's discovery of black hole evaporation, and what it could be teaching us about the foundations of quantum mechanics and gravity.
Uniformly accelerated black holes
NASA Astrophysics Data System (ADS)
Letelier, Patricio S.; Oliveira, Samuel R.
2001-09-01
The static and stationary C metric are examined in a generic framework and their interpretations studied in some detail, especially those with two event horizons, one for the black hole and another for the acceleration. We find that (i) the spacetime of an accelerated static black hole is plagued by either conical singularities or a lack of smoothness and compactness of the black hole horizon, (ii) by using standard black hole thermodynamics we show that accelerated black holes have a higher Hawking temperature than Unruh temperature of the accelerated frame, and (iii) the usual upper bound on the product of the mass and acceleration parameters (<1/27) is just a coordinate artifact. The main results are extended to accelerated rotating black holes with no significant changes.
How to End Colonial Domination of Black America: A Challenge to Black Psychologists
ERIC Educational Resources Information Center
Howard, Joseph Hannibal, III
1970-01-01
Argues that Black people must engage in a therapeutic struggle which stresses Afro-American history and nationalism, and that Black professionals must shed narrow confines of academic disciplines and think as social scientists. (KG)
On Assessing Black Health Status: A Historical Overview.
ERIC Educational Resources Information Center
Rice, Mitchell F.
1986-01-01
Examines Black health status from the slavery period to the present, discusses health status disparities between Blacks and Whites in the areas of life expectancy and infant mortality, and considers socioeconomic factors affecting Black health status. (Author/GC)
Resource Letter BH-1: Black Holes.
ERIC Educational Resources Information Center
Detweiler, Steven
1981-01-01
Lists resources on black holes, including: (1) articles of historical interest; (2) books and journal articles on elementary expositions; (3) elementary and advanced textbooks; and (4) research articles on analytic structure of black holes, black hole dynamics, and astrophysical processes. (SK)
Demeke, Hanna B; Johnson, Anna S; Wu, Baohua; Nwangwu-Ike, Ndidi; King, Hope; Dean, Hazel D
2018-01-27
Despite improvements in its treatment, HIV infection continues to affect Blacks disproportionally. Using National HIV Surveillance System data from 50 U.S. states and the District of Columbia, we examined demographic and epidemiologic differences between U.S.-born and non-U.S.-born Black adults. Of 110,452 Black adults reported with diagnosed HIV during 2008-2014 with complete country of birth information, 11.1% were non-U.S.-born. Non-U.S.-born were more likely to be older, female, have HIV infection attributed to heterosexual contact, have been diagnosed late, and live in the northeastern U.S. region. During 2014, the HIV diagnosis rate among African-born Black females was 1.4 times the rate of U.S.-born Black males, 2 times the rate of African-born Black males, and 5.3 times the rate of U.S.-born Black females. We elucidate the differences between U.S.-born and non-U.S.-born Blacks on which to base culturally appropriate HIV-prevention programs and policies.
Recent advances on bioactivities of black rice.
Dias, Aécio L de S; Pachikian, Barbara; Larondelle, Yvan; Quetin-Leclercq, Joëlle
2017-11-01
Black rice has been consumed for centuries in Asian countries such as China, Korea or Japan. Nowadays, extracts and derivatives are considered as beneficial functional foods because of their high content in several bioactive molecules such as anthocyanins, other phenolics and terpenoids. The purpose of this review is to summarize and discuss recent developments on black rice bioactivities. Some sterols and triterpenoids with potential anticancer properties already tested in vitro and in vivo have been isolated and identified from bran extracts of black rice. Protection against osteoporosis has been suggested for the first time for black rice extracts. Because of its antioxidant and anti-inflammatory properties, black rice also protects liver and kidney from injuries. One clinical study reported the interest of black rice in case of alcohol withdrawal. Several advances have been recently achieved on the understanding of the potential biological effects of black rice and its derivatives. They further confirm that black rice should be considered as a promising source of health-promoting functional foods targeting a large set of noninfectious diseases. However, more clinical studies are needed to support the findings highlighted in this review.
The contribution of preterm birth to the Black-White infant mortality gap, 1990 and 2000.
Schempf, Ashley H; Branum, Amy M; Lukacs, Susan L; Schoendorf, Kenneth C
2007-07-01
We evaluated whether the decline of the racial disparity in preterm birth during the last decade was commensurate with a decline in the contribution of preterm birth to the infant mortality gap. We used linked files of 1990 and 2000 data on US infant births and deaths to partition the gap between Black and White infant mortality rates into differences in the (1) distribution of gestational age and (2) gestational age-specific mortality rates. Between 1990 and 2000, the Black-White infant mortality rate ratio did not change significantly (2.3 vs 2.4). Excess deaths among preterm Black infants accounted for nearly 80% of the Black-White infant mortality gap in both 1990 and 2000. The narrowing racial disparity in the preterm birth rate was counterbalanced by greater mortality reductions in White than in Black preterm infants. Extremely preterm birth (<28 weeks) was 4 times higher in Black infants and accounted for more than half of the infant mortality gap. Substantial reductions in the Black-White infant mortality gap will require improved prevention of extremely preterm birth among Black infants.
Strong field gravitational lensing by a charged Galileon black hole
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhao, Shan-Shan; Xie, Yi, E-mail: clefairy035@163.com, E-mail: yixie@nju.edu.cn
Strong field gravitational lensings are dramatically disparate from those in the weak field by representing relativistic images due to light winds one to infinity loops around a lens before escaping. We study such a lensing caused by a charged Galileon black hole, which is expected to have possibility to evade no-hair theorem. We calculate the angular separations and time delays between different relativistic images of the charged Galileon black hole. All these observables can potentially be used to discriminate a charged Galileon black hole from others. We estimate the magnitudes of these observables for the closest supermassive black hole Sgrmore » A*. The strong field lensing observables of the charged Galileon black hole can be close to those of a tidal Reissner-Nordström black hole or those of a Reissner-Nordström black hole. It will be helpful to distinguish these black holes if we can separate the outermost relativistic images and determine their angular separation, brightness difference and time delay, although it requires techniques beyond the current limit.« less
Entropy bound of horizons for accelerating, rotating and charged Plebanski–Demianski black hole
DOE Office of Scientific and Technical Information (OSTI.GOV)
Debnath, Ujjal, E-mail: ujjaldebnath@yahoo.com
We first review the accelerating, rotating and charged Plebanski–Demianski (PD) black hole, which includes the Kerr–Newman rotating black hole and the Taub-NUT spacetime. The main feature of this black hole is that it has 4 horizons like event horizon, Cauchy horizon and two accelerating horizons. In the non-extremal case, the surface area, entropy, surface gravity, temperature, angular velocity, Komar energy and irreducible mass on the event horizon and Cauchy horizon are presented for PD black hole. The entropy product, temperature product, Komar energy product and irreducible mass product have been found for event horizon and Cauchy horizon. Also their sumsmore » are found for both horizons. All these relations are dependent on the mass of the PD black hole and other parameters. So all the products are not universal for PD black hole. The entropy and area bounds for two horizons have been investigated. Also we found the Christodoulou–Ruffini mass for extremal PD black hole. Finally, using first law of thermodynamics, we also found the Smarr relation for PD black hole.« less
Cosmic censorship conjecture in Kerr-Sen black hole
NASA Astrophysics Data System (ADS)
Gwak, Bogeun
2017-06-01
The validity of the cosmic censorship conjecture for the Kerr-Sen black hole, which is a solution to the low-energy effective field theory for four-dimensional heterotic string theory, is investigated using charged particle absorption. When the black hole absorbs the particle, the charge on it changes owing to the conserved quantities of the particle. Changes in the black hole are constrained to the equation for the motion of the particle and are consistent with the laws of thermodynamics. Particle absorption increases the mass of the Kerr-Sen black hole to more than that of the absorbed charges such as angular momentum and electric charge; hence, the black hole cannot be overcharged. In the near-extremal black hole, we observe a violation of the cosmic censorship conjecture for the angular momentum in the first order of expansion and the electric charge in the second order. However, considering an adiabatic process carrying the conserved quantities as those of the black hole, we prove the stability of the black hole horizon. Thus, we resolve the violation. This is consistent with the third law of thermodynamics.
The role of socioeconomic factors in Black-White disparities in preterm birth.
Braveman, Paula A; Heck, Katherine; Egerter, Susan; Marchi, Kristen S; Dominguez, Tyan Parker; Cubbin, Catherine; Fingar, Kathryn; Pearson, Jay A; Curtis, Michael
2015-04-01
We investigated the role of socioeconomic factors in Black-White disparities in preterm birth (PTB). We used the population-based California Maternal and Infant Health Assessment survey and birth certificate data on 10 400 US-born Black and White California residents who gave birth during 2003 to 2010 to examine rates and relative likelihoods of PTB among Black versus White women, with adjustment for multiple socioeconomic factors and covariables. Greater socioeconomic advantage was generally associated with lower PTB rates among White but not Black women. There were no significant Black-White disparities within the most socioeconomically disadvantaged subgroups; Black-White disparities were seen only within more advantaged subgroups. Socioeconomic factors play an important but complex role in PTB disparities. The absence of Black-White disparities in PTB within certain socioeconomic subgroups, alongside substantial disparities within others, suggests that social factors moderate the disparity. Further research should explore social factors suggested by the literature-including life course socioeconomic experiences and racism-related stress, and the biological pathways through which they operate-as potential contributors to PTB among Black and White women with different levels of social advantage.
REVIEWS OF TOPICAL PROBLEMS: "Magnetized" black holes
NASA Astrophysics Data System (ADS)
Aliev, A. N.; Gal'tsov, D. V.
1989-01-01
Physical aspects of the theory of black holes in an external electromagnetic field are reviewed. The "magnetized" black hole model is currently widely discussed in astrophysics because it provides a basis for the explanation of the high energy activity of galactic cores and quasars. The particular feature of this model is that it predicts unusual "gravimagnetic" phenomena that arise as a result of a natural combination of effects in electrodynamics and gravitation, namely, the appearance of an inductive potential difference during the rotation of a black hole in a magnetic field, the drift of a black hole in an external electromagnetic field, the change in the chemical potential of the event horizon, the creation of an effective ergosphere of a black hole in a magnetic field, and so on. Questions relating to the description of electromagnetic fields in Kerr space-time are examined, including their influence on the space-time metric, the interaction between a rotating charged black hole and an external electromagnetic field, the motion of charged particles near "magnetized" black holes, including their spontaneous and stimulated emission, and the influence of magnetic fields on quantum-mechanical processes in black holes.
Where Are You? Black Mental Health Model
ERIC Educational Resources Information Center
Kirk, Wyatt
1975-01-01
Discusses a model based on a Black position on Black identity and acceptance. Considers, in particular, self-imposed alienation and the cultural neurosis of Black people, which leads to self-defeat in terms of adaptability to the reality of life. (Author)
Black Ethnicity and the Persistence of Ethnogenesis.
ERIC Educational Resources Information Center
Taylor, Ronald L.
1979-01-01
Reviews past research which demonstrates that neither Black corporate pride nor Black ethnicity is a recent phenomenon in American life. Rather, Black ethnogenesis was inspired by the same structural conditions as the development of ethnic identity among White ethnic populations. (Author/KC)
Black Interpretation, Black American Literature, and Grey Audiences.
ERIC Educational Resources Information Center
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)
Mood of the Black Student on Predominantly White Campus
ERIC Educational Resources Information Center
Stone, Winifred O.
1977-01-01
Dimensions of black idenity, alienation, and contemporary attitudes of black students on the predominantly white campus are appraised. The implications of this are considered in relationship to the predisposition for hypertension in a significant percentage of black people. (Author)
The Black "Dumb Jock": An American Sports Tragedy.
ERIC Educational Resources Information Center
Edwards, Harry
1984-01-01
"Dumb jocks" are not born, they are being systematically created. Black student athletes suffer from the outset from disadvantages: the myth of innate Black athletic superiority, the stereotype of the dumb Black, and social forces determining a vulnerability to exploitation. (MSE)
Black walnut as a crop, Black Walnut Symposium, Carbondale, Illinois, August 4-15, 1973.
USDA FS
1973-01-01
Contains 30 papers on black walnut presented at a symposium in Carbondale, Illinois, in August 1973. Subjects covered include black walnut resources, utilization, and marketing; silviculture; tree improvement; nut culture and production; protection; and economics.
K.E. Woeste; W.F. Beineke
2001-01-01
Black walnut is native to the eastern USA and prized for its high-quality timber. Walnut anthracnose, the most important foliar disease of black walnut, is caused by Gnomonia leptostyla. There is no germplasm available that is resistant to the disease. Ramets of 42 black walnut clones, comprising about one-third of the Midwestern USA black walnut...
ERIC Educational Resources Information Center
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…
Global charges of stationary non-Abelian black holes.
Kleihaus, Burkhard; Kunz, Jutta; Navarro-Lérida, Francisco
2003-05-02
We consider stationary axially symmetric black holes in SU(2) Einstein-Yang-Mills-dilaton theory. We present a mass formula for these stationary non-Abelian black holes, which also holds for Abelian black holes. The presence of the dilaton field allows for rotating black holes, which possess nontrivial electric and magnetic gauge fields, but do not carry a non-Abelian charge. We further present a new uniqueness conjecture.
ERIC Educational Resources Information Center
Ibrahim, Awad
2017-01-01
What happens when the syntax of race meets immigrants whose bodies are assumed to be "Black" in North America but who either do not have the history or the conception of Blackness in North America or are not familiar with the North American Black-White dichotomy? Dealing with three empirical studies and a novel, in the present review…
The case for artificial black holes.
Leonhardt, Ulf; Philbin, Thomas G
2008-08-28
The event horizon is predicted to generate particles from the quantum vacuum, an effect that bridges three areas of physics--general relativity, quantum mechanics and thermodynamics. The quantum radiation of real black holes is too feeble to be detectable, but black-hole analogues may probe several aspects of quantum black holes. In this paper, we explain in simple terms some of the motivations behind the study of artificial black holes.
ERIC Educational Resources Information Center
Morah, Tanya M.
A study was conducted to examine the relationship between American mass media and the black community. Subjects were two groups of black midwestern college students--one group studying at a predominantly black university and the other at a mostly white university--with similar social and economic backgrounds. It was hypothesized that black…
Pyrolytic carbon black composite and method of making the same
Naskar, Amit K.; Paranthaman, Mariappan Parans; Bi, Zhonghe
2016-09-13
A method of recovering carbon black includes the step of providing a carbonaceous source material containing carbon black. The carbonaceous source material is contacted with a sulfonation bath to produce a sulfonated material. The sulfonated material is pyrolyzed to produce a carbon black containing product comprising a glassy carbon matrix phase having carbon black dispersed therein. A method of making a battery electrode is also disclosed.
Braunstein, Samuel L; Pati, Arun K
2007-02-23
Can quantum-information theory shed light on black-hole evaporation? By entangling the in-fallen matter with an external system we show that the black-hole information paradox becomes more severe, even for cosmologically sized black holes. We rule out the possibility that the information about the in-fallen matter might hide in correlations between the Hawking radiation and the internal states of the black hole. As a consequence, either unitarity or Hawking's semiclassical predictions must break down. Any resolution of the black-hole information crisis must elucidate one of these possibilities.
Growth of Primordial Black Holes
NASA Astrophysics Data System (ADS)
Harada, Tomohiro
Primordial black holes have important observational implications through Hawking evaporation and gravitational radiation as well as being a candidate for cold dark matter. Those black holes are assumed to have formed in the early universe typically with the mass scale contained within the Hubble horizon at the formation epoch and subsequently accreted mass surrounding them. Numerical relativity simulation shows that primordial black holes of different masses do not accrete much, which contrasts with a simplistic Newtonian argument. We see that primordial black holes larger than the 'super-horizon' primordial black holes have decreasing energy and worm-hole like struture, suggesting the formation through quamtum processes.
Grand unification scale primordial black holes: consequences and constraints.
Anantua, Richard; Easther, Richard; Giblin, John T
2009-09-11
A population of very light primordial black holes which evaporate before nucleosynthesis begins is unconstrained unless the decaying black holes leave stable relics. We show that gravitons Hawking radiated from these black holes would source a substantial stochastic background of high frequency gravititational waves (10(12) Hz or more) in the present Universe. These black holes may lead to a transient period of matter-dominated expansion. In this case the primordial Universe could be temporarily dominated by large clusters of "Hawking stars" and the resulting gravitational wave spectrum is independent of the initial number density of primordial black holes.
Supersonic gas streams enhance the formation of massive black holes in the early universe
NASA Astrophysics Data System (ADS)
Hirano, Shingo; Hosokawa, Takashi; Yoshida, Naoki; Kuiper, Rolf
2017-09-01
Supermassive black holes existed less than a billion years after the Big Bang. Because black holes can grow at a maximum rate that depends on their current mass, it has been difficult to understand how such massive black holes could have formed so quickly. Hirano et al. developed simulations to show that streaming motions—velocity offsets between the gas and dark matter components—could have produced black holes with tens of thousands of solar masses in the early universe. That's big enough to grow into the supermassive black holes that we observe today.
Acceleration of black hole universe
NASA Astrophysics Data System (ADS)
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.
Divergent discourse between protests and counter-protests: #BlackLivesMatter and #AllLivesMatter.
Gallagher, Ryan J; Reagan, Andrew J; Danforth, Christopher M; Dodds, Peter Sheridan
2018-01-01
Since the shooting of Black teenager Michael Brown by White police officer Darren Wilson in Ferguson, Missouri, the protest hashtag #BlackLivesMatter has amplified critiques of extrajudicial killings of Black Americans. In response to #BlackLivesMatter, other Twitter users have adopted #AllLivesMatter, a counter-protest hashtag whose content argues that equal attention should be given to all lives regardless of race. Through a multi-level analysis of over 860,000 tweets, we study how these protests and counter-protests diverge by quantifying aspects of their discourse. We find that #AllLivesMatter facilitates opposition between #BlackLivesMatter and hashtags such as #PoliceLivesMatter and #BlueLivesMatter in such a way that historically echoes the tension between Black protesters and law enforcement. In addition, we show that a significant portion of #AllLivesMatter use stems from hijacking by #BlackLivesMatter advocates. Beyond simply injecting #AllLivesMatter with #BlackLivesMatter content, these hijackers use the hashtag to directly confront the counter-protest notion of "All lives matter." Our findings suggest that Black Lives Matter movement was able to grow, exhibit diverse conversations, and avoid derailment on social media by making discussion of counter-protest opinions a central topic of #AllLivesMatter, rather than the movement itself.
Goings, Trenette Clark; Butler-Bente, Emily; McGovern, Tricia; Howard, Matthew O.
2016-01-01
Most substance-use prevention interventions are based on the implicit assumption that risk and protective factors for substance use are the same for biracial and monoracial youth. However, preliminary research suggests this assumption may be untrue. This study compared the prevalence and correlates of substance use among Black, White, and biracial Black-White youth. Data were derived from the National Longitudinal Study of Adolescent and Adult Health (Add Health), which is a longitudinal investigation using stratified random sampling to study health behaviors. After controlling for sociodemographic factors and using weighted Poisson and logistic regression, we found the substance-use prevalence rates of Black-White youth to be intermediate to the higher rates of Whites and lower rates of Blacks. In addition, Black-White youth’s scores on most covariates were intermediate to those of the monoracial groups. Family factors were more important in explaining higher substance use than other contextual factors. School factors seem to be important in explaining lower substance use for Black-White youth. Correlates of substance use for Black-White youth were not identical to those of either Black or White youth. More research on the observed intermediate phenomena among biracial youth vis-à-vis prevalence, correlates, and causes of substance use is needed. PMID:27427812
NASA Astrophysics Data System (ADS)
Morales Demarco, M.; Oyhantçabal, P.; Stein, K.-J.; Siegesmund, S.
2012-04-01
Dimensional stones with a black color occupy a prominent place on the international market. Uruguayan dolerite dikes of andesitic and andesitic-basaltic composition are mined for commercial blocks of black dimensional stones. A total of 16 dikes of both compositions were studied and samples collected for geochemical and petrographical analysis. Color measurements were performed on different black dimensional stones in order to compare them with the Uruguayan dolerites. Samples of the two commercial varieties (Absolute Black and Moderate Black) were obtained for petrophysical analysis (e.g. density, porosity, uniaxial compressive strength, tensile strength, etc.). Detailed structural analyses were performed in several quarries. Geochemistry and petrography determines the intensity of the black color. When compared with commercial samples from China, Brazil, India and South Africa, among others, the Uruguayan dolerite Absolute Black is the darkest black dimensional stone analyzed. In addition, the petrophysical properties of the Uruguayan dolerites make them one of the highest quality black dimensional stones. Structural analyses show that five joint sets have been recognized: two sub-vertical joints, one horizontal and two diagonal. These joint sets are one of the most important factors that control the deposits, since they control the block size distribution and the amount of waste material.
Novel Cause of 'Black Thyroid': Intraoperative Use of Indocyanine Green.
Chernock, Rebecca D; Jackson, Ryan S
2017-09-01
The antibiotic minocycline is virtually pathognomonic for brown-black discoloration of the thyroid gland referred to as 'black thyroid'. Black thyroid' is an incidental finding in patients taking the drug who undergo thyroid surgery for another indication and is not of known clinical significance. However, its recognition is important so as not to raise concern for a disease process. Here, we present the first case of 'black thyroid' attributable to the iodine-containing compound indocyanine green. Intraoperative indocyanine green was administered as part of a research protocol transoral robotic-assisted surgery for a base of tongue cancer in a 44-year-old man. Hemithyroidectomy was subsequently performed during the same operation for further evaluation of an indeterminate thyroid nodule. The resected thyroid lobe was dark, nearly black in color, and histologically showed extensive brown pigment deposition in the follicular epithelial cells and colloid, mimicking minocycline-induced 'black thyroid'. In this case, however, the patient was not taking minocycline; instead the 'black thyroid' was attributed to the iodine-containing compound indocyanine green. Indocyanine green is a hereto unreported cause of 'black thyroid' with histopathologic features that are remarkably similar to that induced by minocycline. Indocyanine green should be included the differential diagnosis of 'black thyroid'. Clinical history is important so as not to raise concern for a disease process.
Black/White Differences in Perceived Weight and Attractiveness among Overweight Women
Chithambo, Taona P.; Huey, Stanley J.
2013-01-01
Numerous studies have reported that Black women are more satisfied with their bodies than White women. The buffering hypothesis suggests that aspects of Black culture protect Black women against media ideals that promote a slender female body type; therefore, Black women are expected to exhibit higher body esteem than White women. To test this hypothesis, the current study aimed to assess the influence of race on weight perception, perceived attractiveness, and the interrelations between body mass index (BMI) and perceived attractiveness among overweight and obese women. Participants were 1,694 respondents of Wave IV of the National Longitudinal Study on Adolescent Health (M = 28.89 years). Black (n = 531) or White (n = 1163) obese or overweight women were included in the current study. As expected, Black women reported lower perceived weight and higher attractiveness than White women, despite higher body mass for Black women. Furthermore, race moderated the relationship between BMI and perceived attractiveness; for White women, a negative relationship existed between BMI and attractiveness, whereas for Black women, BMI and attractiveness were not related. The study findings provide further support for the buffering hypothesis, indicating that despite higher body mass, overweight Black women are less susceptible to thin body ideals than White women. PMID:23533721
Two ten-billion-solar-mass black holes at the centres of giant elliptical galaxies.
McConnell, Nicholas J; Ma, Chung-Pei; Gebhardt, Karl; Wright, Shelley A; Murphy, Jeremy D; Lauer, Tod R; Graham, James R; Richstone, Douglas O
2011-12-08
Observational work conducted over the past few decades indicates that all massive galaxies have supermassive black holes at their centres. Although the luminosities and brightness fluctuations of quasars in the early Universe suggest that some were powered by black holes with masses greater than 10 billion solar masses, the remnants of these objects have not been found in the nearby Universe. The giant elliptical galaxy Messier 87 hosts the hitherto most massive known black hole, which has a mass of 6.3 billion solar masses. Here we report that NGC 3842, the brightest galaxy in a cluster at a distance from Earth of 98 megaparsecs, has a central black hole with a mass of 9.7 billion solar masses, and that a black hole of comparable or greater mass is present in NGC 4889, the brightest galaxy in the Coma cluster (at a distance of 103 megaparsecs). These two black holes are significantly more massive than predicted by linearly extrapolating the widely used correlations between black-hole mass and the stellar velocity dispersion or bulge luminosity of the host galaxy. Although these correlations remain useful for predicting black-hole masses in less massive elliptical galaxies, our measurements suggest that different evolutionary processes influence the growth of the largest galaxies and their black holes.
The quantum emission spectra of rapidly-rotating Kerr black holes: Discrete or continuous?
NASA Astrophysics Data System (ADS)
Hod, Shahar
2015-10-01
Bekenstein and Mukhanov (BM) have suggested that, in a quantum theory of gravity, black holes may have discrete emission spectra. Using the time-energy uncertainty principle they have also shown that, for a (non-rotating) Schwarzschild black hole, the natural broadening δω of the black-hole emission lines is expected to be small on the scale set by the characteristic frequency spacing Δω of the spectral lines: ζSch ≡ δω / Δω ≪ 1. BM have therefore concluded that the expected discrete emission lines of the quantized Schwarzschild black hole are unlikely to overlap. In this paper we calculate the characteristic dimensionless ratio ζ (a bar) ≡ δω / Δω for the predicted BM emission spectra of rapidly-rotating Kerr black holes (here a bar ≡ J /M2 is the dimensionless angular momentum of the black hole). It is shown that ζ (a bar) is an increasing function of the black-hole angular momentum. In particular, we find that the quantum emission lines of Kerr black holes in the regime a bar ≳ 0.9 are characterized by the dimensionless ratio ζ (a bar) ≳ 1 and are therefore effectively blended together. Our results thus suggest that, even if the underlying mass (energy) spectrum of these rapidly-rotating Kerr black holes is fundamentally discrete as suggested by Bekenstein and Mukhanov, the natural broadening phenomenon (associated with the time-energy uncertainty principle) is expected to smear the black-hole radiation spectrum into a continuum.
Bowleg, Lisa; English, Devin; del Rio-Gonzalez, Ana Maria; Burkholder, Gary J.; Teti, Michelle; Tschann, Jeanne M.
2015-01-01
Although extensive research documents that Black people in the U.S. frequently experience social discrimination, most of this research aggregates these experiences primarily or exclusively by race. Consequently, empirical gaps exist about the psychosocial costs and benefits of Black men’s experiences at the intersection of race and gender. Informed by intersectionality, a theoretical framework that highlights how multiple social identities intersect to reflect interlocking social-structural inequality, this study addresses these gaps with the qualitative development and quantitative test of the Black Men’s Experiences Scale (BMES). The BMES assesses Black men’s negative experiences with overt discrimination and microaggressions, as well their positive evaluations of what it means to be Black men. First, we conducted focus groups and individual interviews with Black men to develop the BMES. Next, we tested the BMES with 578 predominantly low-income urban Black men between the ages of 18 and 44. Exploratory factor analysis suggested a 12-item, 3-factor solution that explained 63.7% of the variance. We labeled the subscales: Overt Discrimination, Microaggressions, and Positives: Black Men. Confirmatory factor analysis supported the three-factor solution. As hypothesized, the BMES’s subscales correlated with measures of racial discrimination, depression, resilience, and social class at the neighborhood-level. Preliminary evidence suggests that the BMES is a reliable and valid measure of Black men’s experiences at the intersection of race and gender. PMID:27087786
Bowleg, Lisa; English, Devin; Del Rio-Gonzalez, Ana Maria; Burkholder, Gary J; Teti, Michelle; Tschann, Jeanne M
2016-04-01
Although extensive research documents that Black people in the U.S. frequently experience social discrimination, most of this research aggregates these experiences primarily or exclusively by race. Consequently, empirical gaps exist about the psychosocial costs and benefits of Black men's experiences at the intersection of race and gender. Informed by intersectionality, a theoretical framework that highlights how multiple social identities intersect to reflect interlocking social-structural inequality, this study addresses these gaps with the qualitative development and quantitative test of the Black Men's Experiences Scale (BMES). The BMES assesses Black men's negative experiences with overt discrimination and microaggressions, as well their positive evaluations of what it means to be Black men. First, we conducted focus groups and individual interviews with Black men to develop the BMES. Next, we tested the BMES with 578 predominantly low-income urban Black men between the ages of 18 and 44. Exploratory factor analysis suggested a 12-item, 3-factor solution that explained 63.7% of the variance. We labeled the subscales: Overt Discrimination, Microaggressions, and Positives: Black Men . Confirmatory factor analysis supported the three-factor solution. As hypothesized, the BMES's subscales correlated with measures of racial discrimination, depression, resilience, and social class at the neighborhood-level. Preliminary evidence suggests that the BMES is a reliable and valid measure of Black men's experiences at the intersection of race and gender.
Socioeconomic Factors Affecting Local Support for Black Bear Recovery Strategies
NASA Astrophysics Data System (ADS)
Morzillo, Anita T.; Mertig, Angela G.; Hollister, Jeffrey W.; Garner, Nathan; Liu, Jianguo
2010-06-01
There is global interest in recovering locally extirpated carnivore species. Successful efforts to recover Louisiana black bear in Louisiana have prompted interest in recovery throughout the species’ historical range. We evaluated support for three potential black bear recovery strategies prior to public release of a black bear conservation and management plan for eastern Texas, United States. Data were collected from 1,006 residents living in proximity to potential recovery locations, particularly Big Thicket National Preserve. In addition to traditional logistic regression analysis, we used conditional probability analysis to statistically and visually evaluate probabilities of public support for potential black bear recovery strategies based on socioeconomic characteristics. Allowing black bears to repopulate the region on their own (i.e., without active reintroduction) was the recovery strategy with the greatest probability of acceptance. Recovery strategy acceptance was influenced by many socioeconomic factors. Older and long-time local residents were most likely to want to exclude black bears from the area. Concern about the problems that black bears may cause was the only variable significantly related to support or non-support across all strategies. Lack of personal knowledge about black bears was the most frequent reason for uncertainty about preferred strategy. In order to reduce local uncertainty about possible recovery strategies, we suggest that wildlife managers focus outreach efforts on providing local residents with general information about black bears, as well as information pertinent to minimizing the potential for human-black bear conflict.
Launching of Active Galactic Nuclei Jets
NASA Astrophysics Data System (ADS)
Tchekhovskoy, Alexander
As black holes accrete gas, they often produce relativistic, collimated outflows, or jets. Jets are expected to form in the vicinity of a black hole, making them powerful probes of strong-field gravity. However, how jet properties (e.g., jet power) connect to those of the accretion flow (e.g., mass accretion rate) and the black hole (e.g., black hole spin) remains an area of active research. This is because what determines a crucial parameter that controls jet properties—the strength of large-scale magnetic flux threading the black hole—remains largely unknown. First-principles computer simulations show that due to this, even if black hole spin and mass accretion rate are held constant, the simulated jet powers span a wide range, with no clear winner. This limits our ability to use jets as a quantitative diagnostic tool of accreting black holes. Recent advances in computer simulations demonstrated that accretion disks can accumulate large-scale magnetic flux on the black hole, until the magnetic flux becomes so strong that it obstructs gas infall and leads to a magnetically-arrested disk (MAD). Recent evidence suggests that central black holes in jetted active galactic nuclei and tidal disruptions are surrounded by MADs. Since in MADs both the black hole magnetic flux and the jet power are at their maximum, well-defined values, this opens up a new vista in the measurements of black hole masses and spins and quantitative tests of accretion and jet theory.
Demographic but not geographic insularity in HIV transmission among young black MSM.
Oster, Alexandra M; Pieniazek, Danuta; Zhang, Xinjian; Switzer, William M; Ziebell, Rebecca A; Mena, Leandro A; Wei, Xierong; Johnson, Kendra L; Singh, Sonita K; Thomas, Peter E; Elmore, Kimberlee A; Heffelfinger, James D
2011-11-13
To understand patterns of HIV transmission among young black MSM and others in Mississippi. Phylogenetic analysis of HIV-1 polymerase (pol) sequences from 799 antiretroviral-naive persons newly diagnosed with HIV infection in Mississippi during 2005-2008, 130 (16%) of whom were black MSM aged 16-25 years. We identified phylogenetic clusters and used surveillance data to evaluate demographic attributes and risk factors of all persons in clusters that included black MSM aged 16-25 years. We identified 82 phylogenetic clusters, 21 (26%) of which included HIV strains from at least one young black MSM. Of the 69 persons in these clusters, 59 were black MSM and seven were black men with unknown transmission category; the remaining three were MSM of white or Hispanic race/ethnicity. Of these 21 clusters, 10 included residents of one geographic region of Mississippi, whereas 11 included residents of multiple regions or outside of the state. Phylogenetic clusters involving HIV-infected young black MSM were homogeneous with respect to demographic and risk characteristics, suggesting insularity of this population with respect to HIV transmission, but were geographically heterogeneous. Reducing HIV transmission among young black MSM in Mississippi may require prevention strategies that are tailored to young black MSM and those in their sexual networks, and prevention interventions should be delivered in a manner to reach young black MSM throughout the state. Phylogenetic analysis can be a tool for local jurisdictions to understand the transmission dynamics in their areas.
Madkour, Aubrey Spriggs; Harville, Emily Wheeler; Xie, Yiqiong
2013-01-01
Objective To study the relationship between neighborhood demographic characteristics (disadvantage, racial concentration) and the birthweight of infants born to adolescent mothers, potentially as mediated by smoking, prenatal care use, or perceptions of neighborhood safety. Methods Data from Waves I and IV of the National Longitudinal Survey of Adolescent Health were analyzed. Birthweight (continuous) and low birthweight (<2.5 kg) of singleton infants born to non-Hispanic Black and non-Hispanic White adolescent mothers (<20 years) after Wave I were examined as outcomes. Neighborhood demographic characteristics included Census Block Group socioeconomic disadvantage and Black racial concentration. Possible mediators (smoking during pregnancy, early initiation of prenatal care, and perceptions of safety) were also examined. Controls for adolescent baseline age, age at pregnancy, body mass index (BMI) and parental education were included. Analyses were run stratified on race. Results Baseline continuous birthweight, BMI and neighborhood demographics varied significantly between non-Hispanic Black and White adolescent mothers, with Black adolescent mothers evidencing lower birthweight and higher BMI, neighborhood disadvantage and Black racial concentration. In multivariable analyses among Black adolescent mothers, Black racial concentration was positively associated with birthweight, and negatively associated with low birthweight; no mediators were supported. Neighborhood disadvantage and Black racial concentration were unassociated with birthweight outcomes among White adolescent mothers. Conclusions Infants born to Black adolescent mothers evidenced higher birthweight with increasing Black neighborhood concentration. Further exploration of mechanisms by which Black racial concentration may positively impact birthweight is warranted. PMID:23771237
ERIC Educational Resources Information Center
Journal of Blacks in Higher Education, 1999
1999-01-01
Collection of articles, examines issues related to African Americans in higher education. Topics include black faculty; educational finance; law schools; black colleges; private universities; enrollment trends; high achieving African immigrants; bridging the racial computer gap; black women compared to black men and to white women in doctoral…
NASA Technical Reports Server (NTRS)
Garcia, Michael R.; Oliversen, Ronald J. (Technical Monitor)
2002-01-01
The goal of this program is to study black holes, both in our Galaxy and in nearby galaxies. We aim to study both "stellar mass" x-ray binaries containing black holes (both in our Galaxy and in nearby galaxies), and super-massive black holes in nearby galaxies.
NASA Technical Reports Server (NTRS)
Oliversen, Ronald (Technical Monitor); Garcia, Michael
2005-01-01
The goal of this program is to study black holes, both in our Galaxy and in nearby galaxies. We aim to study both 'stellar mass' x-ray binaries containing black holes (both in our Galaxy and in nearby galaxies), and super-massive black holes in nearby galaxies.
Simulations of binary black hole mergers
NASA Astrophysics Data System (ADS)
Lovelace, Geoffrey
2017-01-01
Advanced LIGO's observations of merging binary black holes have inaugurated the era of gravitational wave astronomy. Accurate models of binary black holes and the gravitational waves they emit are helping Advanced LIGO to find as many gravitational waves as possible and to learn as much as possible about the waves' sources. These models require numerical-relativity simulations of binary black holes, because near the time when the black holes merge, all analytic approximations break down. Following breakthroughs in 2005, many research groups have built numerical-relativity codes capable of simulating binary black holes. In this talk, I will discuss current challenges in simulating binary black holes for gravitational-wave astronomy, and I will discuss the tremendous progress that has already enabled such simulations to become an essential tool for Advanced LIGO.
Searcy, Yan
2018-05-14
Market-based approaches to addressing racial disparities have essentially re-commodified Blackness. Utilizing Hartford, which contains the largest percentage of Blacks per capita in Connecticut, this article examines market-based approaches to address racial disparities while discussing Blackness as an enduring commodity that is tied to private sector profit. The study argues that market based approaches incentivize punitive approaches to social problems associated with Blackness. The study concludes by suggesting that addressing disparities utilizing markets requires reimagining policy incentives to focus on prevention and treatment of social problems associated with Blackness. Failure to reimagine policy incentives serves to commodify Blackness whereby industries benefit from the continuity of disparities rather than the elimination of disparities.
Escape of black holes from the brane.
Flachi, Antonino; Tanaka, Takahiro
2005-10-14
TeV-scale gravity theories allow the possibility of producing small black holes at energies that soon will be explored at the CERN LHC or at the Auger observatory. One of the expected signatures is the detection of Hawking radiation that might eventually terminate if the black hole, once perturbed, leaves the brane. Here, we study how the "black hole plus brane" system evolves once the black hole is given an initial velocity that mimics, for instance, the recoil due to the emission of a graviton. The results of our dynamical analysis show that the brane bends around the black hole, suggesting that the black hole eventually escapes into the extra dimensions once two portions of the brane come in contact and reconnect. This gives a dynamical mechanism for the creation of baby branes.
Effect of black point on accuracy of LCD displays colorimetric characterization
NASA Astrophysics Data System (ADS)
Li, Tong; Xie, Kai; He, Nannan; Ye, Yushan
2018-03-01
Black point is the point at which RGB's single channel digital drive value is 0. Due to the problem of light leakage of liquid-crystal displays (LCDs), black point's luminance value is not 0, this phenomenon bring some errors to colorimetric characterization of LCDs, especially low luminance value driving greater sampling effect. This paper describes the characteristic accuracy of polynomial model method and the effect of black point on accuracy, the color difference accuracy is given. When considering the black point in the characteristics equation, the maximum color difference is 3.246, the maximum color difference than without considering the black points reduced by 2.36. The experimental results show that the accuracy of LCDs colorimetric characterization can be improved, if the effect of black point is eliminated properly.
Dilatonic BTZ black holes with power-law field
NASA Astrophysics Data System (ADS)
Hendi, S. H.; Eslam Panah, B.; Panahiyan, S.; Sheykhi, A.
2017-04-01
Motivated by low energy effective action of string theory and numerous applications of BTZ black holes, we will consider minimal coupling between dilaton and nonlinear electromagnetic fields in three dimensions. The main goal is studying thermodynamical structure of black holes in this set up. Temperature and heat capacity of these black holes are investigated and a picture regarding their phase transitions is given. In addition, the role and importance of studying the mass of black holes is highlighted. We will see how different parameters modify thermodynamical quantities, hence thermodynamical structure of these black holes. In addition, geometrical thermodynamics is used to investigate thermodynamical properties of these black holes. In this regard, the successful method is presented and the nature of interaction around bound and phase transition points is studied.
For Black men, being tall increases threat stereotyping and police stops.
Hester, Neil; Gray, Kurt
2018-03-13
Height seems beneficial for men in terms of salaries and success; however, past research on height examines only White men. For Black men, height may be more costly than beneficial, primarily signaling threat rather than competence. Three studies reveal the downsides of height in Black men. Study 1 analyzes over 1 million New York Police Department stop-and-frisk encounters and finds that tall Black men are especially likely to receive unjustified attention from police. Then, studies 2 and 3 experimentally demonstrate a causal link between perceptions of height and perceptions of threat for Black men, particularly for perceivers who endorse stereotypes that Black people are more threatening than White people. Together, these data reveal that height is sometimes a liability for Black men, particularly in contexts in which threat is salient.
Understanding Masculinity in Undergraduate African American Men: A Qualitative Study.
Mincey, Krista; Alfonso, Moya; Hackney, Amy; Luque, John
2014-09-01
This study reports findings on views of masculinity with undergraduate Black men, which included interviews and focus groups (N = 46) with participants ranging in age from 18 to 22 years. Specifically, this study explored how Black men define being a man and being a Black man. Undergraduate Black males at a historically Black college and university (N = 25) and a predominately White institution (N = 21) in the Southeastern United States were recruited to participate in this study. Through the use of thematic analysis, findings indicated that three levels of masculinity exist for Black men: what it means to be a man, what it means to be a Black man, and who influences male development. Implications and recommendations for future research and practice are discussed. © The Author(s) 2013.
Smith, Evan M; Panjwani, Deep; Ginn, James; Warren, Andrew P; Long, Christopher; Figuieredo, Pedro; Smith, Christian; Nath, Janardan; Perlstein, Joshua; Walter, Nick; Hirschmugl, Carol; Peale, Robert E; Shelton, David
2016-03-10
Infrared-absorbing gold black has been selectively patterned onto the active surfaces of a vanadium-oxide-based infrared bolometer array. Patterning by metal lift-off relies on protection of the fragile gold black with an evaporated oxide, which preserves much of gold black's high absorptance. This patterned gold black also survives the dry-etch removal of the sacrificial polyimide used to fabricate the air-bridge bolometers. For our fabricated devices, infrared responsivity is improved 22% in the long-wave IR and 70% in the mid-wave IR by the gold black coating, with no significant change in detector noise, using a 300°C blackbody and 80 Hz chopping rate. The increase in the time constant caused by the additional mass of gold black is ∼15%.
The Fossil Record of Black Hole Seeds, with Spatially Resolved Spectroscopy
NASA Astrophysics Data System (ADS)
Trump, Jonathan R.; CANDELS, 3D-HST
2016-01-01
I will present the first robust measurement of black hole occupation over a wide range of host galaxy mass (8
Coleman, M Nicole; Butler, Ebony O; Long, Amanda M; Fisher, Felicia D
2016-10-01
Hip-hop media and Black-oriented reality television are powerful mechanisms for conveying and promoting stereotypes of Black women. Black women's sexuality is frequently presented as highly-salient in each medium. However, little is known about the impact of those images on Black women's sexuality and identity. The current study uses focus-group methodology to engage young adult Black in critical discussion of two predominant sexual scripts found in hip-hop music and Black-oriented reality television - the Freak and the Gold Digger. Analyses revealed shared and distinct aspects of each sexual script represented in both media and the impact of those scripts on participants' experiences. Implications for future research are discussed.
Binary black hole in a double magnetic monopole field
NASA Astrophysics Data System (ADS)
Rodriguez, Maria J.
2018-01-01
Ambient magnetic fields are thought to play a critical role in black hole jet formation. Furthermore, dual electromagnetic signals could be produced during the inspiral and merger of binary black hole systems. In this paper, we derive the exact solution for the electromagnetic field occurring when a static, axisymmetric binary black hole system is placed in the field of two magnetic or electric monopoles. As a by-product of this derivation, we also find the exact solution of the binary black hole configuration in a magnetic or electric dipole field. The presence of conical singularities in the static black hole binaries represent the gravitational attraction between the black holes that also drag the external two monopole field. We show that these off-balance configurations generate no energy outflows.
Black Holes in the Cosmos, the Lab, and in Fundamental Physics (1/3)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Giddings, Steve
2010-09-08
Black holes present the extreme limits of physics. They are ubiquitous in the cosmos, and in some extra-dimensional scenarios they could be produced at colliders. They have also yielded a puzzle that challenges the foundations of physics. These talks will begin with an overview of the basics of black hole physics, and then briefly summarize some of the exciting developments with cosmic black holes. They will then turn to properties of quantum black holes, and the question of black hole production in high energy collisions, perhaps beginning with the LHC. I will then overview the apparent paradox emerging from Hawking'smore » discovery of black hole evaporation, and what it could be teaching us about the foundations of quantum mechanics and gravity.« less
Black Holes in the Cosmos, the Lab, and in Fundamental Physics (2/3)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Giddings, Steven
2010-09-07
Black holes present the extreme limits of physics. They are ubiquitous in the cosmos, and in some extra-dimensional scenarios they could be produced at colliders. They have also yielded a puzzle that challenges the foundations of physics. These talks will begin with an overview of the basics of black hole physics, and then briefly summarize some of the exciting developments with cosmic black holes. They will then turn to properties of quantum black holes, and the question of black hole production in high energy collisions, perhaps beginning with the LHC. I will then overview the apparent paradox emerging from Hawking'smore » discovery of black hole evaporation, and what it could be teaching us about the foundations of quantum mechanics and gravity.« less
When Charged Black Holes Merge
NASA Astrophysics Data System (ADS)
Kohler, Susanna
2016-08-01
Most theoretical models assume that black holes arent charged. But a new study shows that mergers of charged black holes could explain a variety of astrophysical phenomena, from fast radio bursts to gamma-ray bursts.No HairThe black hole no hair theorem states that all black holes can be described by just three things: their mass, their spin, and their charge. Masses and spins have been observed and measured, but weve never measured the charge of a black hole and its widely believed that real black holes dont actually have any charge.That said, weve also never shown that black holes dont have charge, or set any upper limits on the charge that they might have. So lets suppose, for a moment, that its possible for a black hole to be charged. How might that affect what we know about the merger of two black holes? A recent theoretical study by Bing Zhang (University of Nevada, Las Vegas) examines this question.Intensity profile of a fast radio burst, a sudden burst of radio emission that lasts only a few milliseconds. [Swinburne Astronomy Productions]Driving TransientsZhangs work envisions a pair of black holes in a binary system. He argues that if just one of the black holes carries charge possibly retained by a rotating magnetosphere then it may be possible for the system to produce an electromagnetic signal that could accompany gravitational waves, such as a fast radio burst or a gamma-ray burst!In Zhangs model, the inspiral of the two black holes generates a global magnetic dipole thats perpendicular to the plane of the binarys orbit. The magnetic flux increases rapidly as the separation between the black holes decreases, generating an increasingly powerful magnetic wind. This wind, in turn, can give rise to a fast radio burst or a gamma-ray burst, depending on the value of the black holes charge.Artists illustration of a short gamma-ray burst, thought to be caused by the merger of two compact objects. [ESO/A. Roquette]Zhang calculates lower limits on the charge necessary to produce each phenomenon. For a 10-solar-mass black hole, he finds that the merger can generate a fast radio burst if the black holes charge is more than ~1012 Coulombs (roughly one billion times the charge that travels through a AA battery from full to empty). If its charge is more than ~1016 Coulombs, it can generate a gamma-ray burst.Limits on ChargeZhangs calculations are not just useful in the hypothetical scenario where black holes are charged. They could, in fact, be a way of testing whether black holes are charged.As we accumulate future gravitational-wave observations (and with two observations by LIGO already announced, it seems likely that there will be many more), we will grow a larger sample of follow-up observations in radio through gamma-ray wavelengths. Our detections or our lack of detections of fast radio bursts or gamma-ray bursts associated with these black-hole mergers will allow us to set some of the first real limits on the charge of black holes.CitationBing Zhang 2016 ApJ 827 L31. doi:10.3847/2041-8205/827/2/L31
Effect of Black maca (Lepidium meyenii) on one spermatogenic cycle in rats.
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.
Racial disparities in molecular subtypes of endometrial cancer.
Dubil, Elizabeth A; Tian, Chunqiao; Wang, Guisong; Tarney, Christopher M; Bateman, Nicholas W; Levine, Douglas A; Conrads, Thomas P; Hamilton, Chad A; Maxwell, George Larry; Darcy, Kathleen M
2018-04-01
Racial differences in the molecular subtypes of endometrial cancer and associations with progression-free survival (PFS) were evaluated. Molecular, clinical and PFS data were acquired from the Cancer Genome Atlas (TCGA) including classification into the integrative, somatic copy number alteration and transcript-based subtypes. The prevalence and prognostic value of the aggressive molecular subtypes (copy number variant [CNV]-high, cluster 4 or mitotic) were evaluated in Black and White patients. There were 337 patients including 14% self-designated as Black, 27% with advanced stage, and 82% with endometrioid histology. The CNV-high subtype was more common in Black than White patients (61.9% vs. 23.5%, P=0.0005) and suggested worse PFS in Black patients (hazard ratio [HR]=3.4, P=0.189). The cluster 4 subtype was more prevalent in Black patients (56.8% vs. 20.9%, P<0.0001) and associated with worse PFS in Black patients (HR=3.4, P=0.049). The mitotic subtype was more abundant in Black patients (64.1% vs. 33.7%, P=0.002), indicated worse PFS in Black patients (HR=4.1, P=0.044) including the endometrioid histology (HR=6.1, P=0.024) and exhibited race-associated enrichment in cell cycle signaling and pathways in cancer including PLK1 and BIRC7. All of these aggressive molecular subtypes also indicated worse PFS in White patients, with unique enrichments in mitotic signaling different from Black patients. The aggressive molecular subtypes from TCGA were more common in Black endometrial cancer patients and indicated worse PFS in both Black and White patients. The mitotic subtypes also indicated worse PFS in Black patients with endometrioid histology. Enrichment patterns in mitotic signaling may represent therapeutic opportunities. Copyright © 2017. Published by Elsevier Inc.
Lara-Díaz, Víctor Javier; Gaytán-Ramos, Angel A; Dávalos-Balderas, Alfredo José; Santos-Guzmán, Jesús; Mata-Cárdenas, Benito David; Vargas-Villarreal, Javier; Barbosa-Quintana, Alvaro; Sanson, Misu; López-Reyes, Alberto Gabriel; Moreno-Cuevas, Jorge E
2009-02-01
We investigated the microbiological and toxicological effects of three Perla black bean extracts on the growth and culture of selected pathogenic microorganisms, the toxicity over Vero cell lines and an in vivo rat model. Three different solvents were used to obtain Perla black bean extracts. All three Perla black bean extracts were tested for antibacterial and antiparasitic activity and further analysed for intrinsic cytotoxicity (IC(50)). Methanol Perla black bean extract was used for acute toxicity test in rats, with the up-and-down doping method. All Perla black bean extracts inhibited bacterial growth. Pseudomonas aeruginosa, Proteus vulgaris, Klebsiella oxytoca, Enterococcus faecalis, Staphylococcus aureus, Staphylococcus epidermidis and Listeria monocytogenes showed inhibition, while Escherichia coli and Enterobacter aerogenes did not. Acidified water and acetic acid Perla black bean extract were tested in parasites. The best IC(50) was observed for Giardia lamblia, while higher concentrations were active against Entamoeba histolytica and Trichomonas vaginalis. The Vero cells toxicity levels (IC(50)) for methanol, acidified water and acetic acid Perla black bean extract were [mean +/- S.D. (95% CI)]: 275 +/- 6.2 (267.9-282.0), 390 +/- 4.6 (384.8-395.2) and 209 +/- 3.39 (205.6-212.4) microg/ml, respectively. In vivo acute toxicity assays did not show changes in absolute organ weights, gross and histological examinations of selected tissues or functional tests. The acetic acid and methanol Perla black bean extract proved to exhibit strong antibacterial activity and the acidified water Perla black bean extract exerted parasiticidal effects against Giardia lamblia, Entamoeba hystolitica and Trichomonas vaginalis. The three Perla black bean extracts assayed over Vero cells showed very low toxicity and the methanol Perla black bean extract in vivo did not cause toxicity.
Particle motion and Penrose processes around rotating regular black hole
NASA Astrophysics Data System (ADS)
Abdujabbarov, Ahmadjon
2016-07-01
The neutral particle motion around rotating regular black hole that was derived from the Ayón-Beato-García (ABG) black hole solution by the Newman-Janis algorithm in the preceding paper (Toshmatov et al., Phys. Rev. D, 89:104017, 2014) has been studied. The dependencies of the ISCO (innermost stable circular orbits along geodesics) and unstable orbits on the value of the electric charge of the rotating regular black hole have been shown. Energy extraction from the rotating regular black hole through various processes has been examined. We have found expression of the center of mass energy for the colliding neutral particles coming from infinity, based on the BSW (Baňados-Silk-West) mechanism. The electric charge Q of rotating regular black hole decreases the potential of the gravitational field as compared to the Kerr black hole and the particles demonstrate less bound energy at the circular geodesics. This causes an increase of efficiency of the energy extraction through BSW process in the presence of the electric charge Q from rotating regular black hole. Furthermore, we have studied the particle emission due to the BSW effect assuming that two neutral particles collide near the horizon of the rotating regular extremal black hole and produce another two particles. We have shown that efficiency of the energy extraction is less than the value 146.6 % being valid for the Kerr black hole. It has been also demonstrated that the efficiency of the energy extraction from the rotating regular black hole via the Penrose process decreases with the increase of the electric charge Q and is smaller in comparison to 20.7 % which is the value for the extreme Kerr black hole with the specific angular momentum a= M.
Linear perturbations of black holes: stability, quasi-normal modes and tails
NASA Astrophysics Data System (ADS)
Zhidenko, Alexander
2009-03-01
Black holes have their proper oscillations, which are called the quasi-normal modes. The proper oscillations of astrophysical black holes can be observed in the nearest future with the help of gravitational wave detectors. Quasi-normal modes are also very important in the context of testing of the stability of black objects, the anti-de Sitter/Conformal Field Theory (AdS/CFT) correspondence and in higher dimensional theories, such as the brane-world scenarios and string theory. This dissertation reviews a number of works, which provide a thorough study of the quasi-normal spectrum of a wide class of black holes in four and higher dimensions for fields of various spin and gravitational perturbations. We have studied numerically the dependance of the quasi-normal modes on a number of factors, such as the presence of the cosmological constant, the Gauss-Bonnet parameter or the aether in the space-time, the dependance of the spectrum on parameters of the black hole and fields under consideration. By the analysis of the quasi-normal spectrum, we have studied the stability of higher dimensional Reissner-Nordstrom-de Sitter black holes, Kaluza-Klein black holes with squashed horizons, Gauss-Bonnet black holes and black strings. Special attention is paid to the evolution of massive fields in the background of various black holes. We have considered their quasi-normal ringing and the late-time tails. In addition, we present two new numerical techniques: a generalisation of the Nollert improvement of the Frobenius method for higher dimensional problems and a qualitatively new method, which allows to calculate quasi-normal frequencies for black holes, which metrics are not known analytically.
NASA Astrophysics Data System (ADS)
Salcido, Jaime; Bower, Richard G.; Theuns, Tom; McAlpine, Stuart; Schaller, Matthieu; Crain, Robert A.; Schaye, Joop; Regan, John
2016-11-01
We estimate the expected event rate of gravitational wave signals from mergers of supermassive black holes that could be resolved by a space-based interferometer, such as the Evolved Laser Interferometer Space Antenna (eLISA), utilizing the reference cosmological hydrodynamical simulation from the EAGLE suite. These simulations assume a Lambda cold dark matter cosmogony with state-of-the-art subgrid models for radiative cooling, star formation, stellar mass loss, and feedback from stars and accreting black holes. They have been shown to reproduce the observed galaxy population with unprecedented fidelity. We combine the merger rates of supermassive black holes in EAGLE with the latest phenomenological waveform models to calculate the gravitational waves signals from the intrinsic parameters of the merging black holes. The EAGLE models predict ˜2 detections per year by a gravitational wave detector such as eLISA. We find that these signals are largely dominated by mergers between seed mass black holes merging at redshifts between z ˜ 2 and z ˜ 1. In order to investigate the dependence on the assumed black hole seed mass, we introduce an additional model with a black hole seed mass an order of magnitude smaller than in our reference model. We also consider a variation of the reference model where a prescription for the expected delays in the black hole merger time-scale has been included after their host galaxies merge. We find that the merger rate is similar in all models, but that the initial black hole seed mass could be distinguished through their detected gravitational waveforms. Hence, the characteristic gravitational wave signals detected by eLISA will provide profound insight into the origin of supermassive black holes and the initial mass distribution of black hole seeds.
Spacetime and orbits of bumpy black holes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vigeland, Sarah J.; Hughes, Scott A.
2010-01-15
Our Universe contains a great number of extremely compact and massive objects which are generally accepted to be black holes. Precise observations of orbital motion near candidate black holes have the potential to determine if they have the spacetime structure that general relativity demands. As a means of formulating measurements to test the black hole nature of these objects, Collins and Hughes introduced ''bumpy black holes'': objects that are almost, but not quite, general relativity's black holes. The spacetimes of these objects have multipoles that deviate slightly from the black hole solution, reducing to black holes when the deviation ismore » zero. In this paper, we extend this work in two ways. First, we show how to introduce bumps which are smoother and lead to better behaved orbits than those in the original presentation. Second, we show how to make bumpy Kerr black holes--objects which reduce to the Kerr solution when the deviation goes to zero. This greatly extends the astrophysical applicability of bumpy black holes. Using Hamilton-Jacobi techniques, we show how a spacetime's bumps are imprinted on orbital frequencies, and thus can be determined by measurements which coherently track the orbital phase of a small orbiting body. We find that in the weak field, orbits of bumpy black holes are modified exactly as expected from a Newtonian analysis of a body with a prescribed multipolar structure, reproducing well-known results from the celestial mechanics literature. The impact of bumps on strong-field orbits is many times greater than would be predicted from a Newtonian analysis, suggesting that this framework will allow observations to set robust limits on the extent to which a spacetime's multipoles deviate from the black hole expectation.« less
ERIC Educational Resources Information Center
Gill, Wanda E.
2013-01-01
The 2013 Black History Month Programs at the U.S. Department of Education highlighted and celebrated emancipation, Civil Rights, the histories of key Black organizations and the contributions of Historically Black Colleges and Universities through a series of programs offered both in Barnard Auditorium at headquarters on Maryland Avenue, S.W,…
Spacetime Non-Commutativity Corrections to the Cardy-Verlinde Formula of Achúcarro-Ortiz Black Hole
NASA Astrophysics Data System (ADS)
Setare, M. R.
2007-02-01
In this letter we compute the corrections to the Cardy-Verlinde formula of Achúcarro-Ortiz black hole, which is the most general two-dimensional black hole derived from the three-dimensional rotating Banados-Teitelboim-Zanelli black hole. These corrections stem from the space non-commutativity. We show that in non-commutative case, non-rotating Achúcarro-Ortiz black hole in contrast with commutative case has two horizons.
ERIC Educational Resources Information Center
Burgett, Paul Joseph
The focus of this dissertation is on two central issues: (1) significant aesthetic theories developed by black scholars which treat the music of black Americans, and (2) the implications which these theories suggest for the development of curricula at all educational levels which treat the music of black Americans. The aesthetic theories selected…
Modified carbon black materials for lithium-ion batteries
Kostecki, Robert; Richardson, Thomas; Boesenberg, Ulrike; Pollak, Elad; Lux, Simon
2016-06-14
A lithium (Li) ion battery comprising a cathode, a separator, an organic electrolyte, an anode, and a carbon black conductive additive, wherein the carbon black has been heated treated in a CO.sub.2 gas environment at a temperature range of between 875-925 degrees Celsius for a time range of between 50 to 70 minutes to oxidize the carbon black and reduce an electrochemical reactivity of the carbon black towards the organic electrolyte.
Blaho, Miklos; Herczeg, Tamas; Kriska, Gyorgy; Egri, Adam; Szaz, Denes; Farkas, Alexandra; Tarjanyi, Nikolett; Czinke, Laszlo; Barta, Andras; Horvath, Gabor
2014-01-01
The horizontally polarizing surface parts of shiny black cars (the reflection-polarization characteristics of which are similar to those of water surfaces) attract water-leaving polarotactic insects. Thus, shiny black cars are typical sources of polarized light pollution endangering water-leaving insects. A new fashion fad is to make car-bodies matt black or grey. Since rough (matt) surfaces depolarize the reflected light, one of the ways of reducing polarized light pollution is to make matt the concerned surface. Consequently, matt black/grey cars may not induce polarized light pollution, which would be an advantageous feature for environmental protection. To test this idea, we performed field experiments with horizontal shiny and matt black car-body surfaces laid on the ground. Using imaging polarimetry, in multiple-choice field experiments we investigated the attractiveness of these test surfaces to various water-leaving polarotactic insects and obtained the following results: (i) The attractiveness of black car-bodies to polarotactic insects depends in complex manner on the surface roughness (shiny, matt) and species (mayflies, dolichopodids, tabanids). (ii) Non-expectedly, the matt dark grey car finish is much more attractive to mayflies (being endangered and protected in many countries) than matt black finish. (iii) The polarized light pollution of shiny black cars usually cannot be reduced with the use of matt painting. On the basis of these, our two novel findings are that (a) matt car-paints are highly polarization reflecting, and (b) these matt paints are not suitable to repel polarotactic insects. Hence, the recent technology used to make matt the car-bodies cannot eliminate or even can enhance the attractiveness of black/grey cars to water-leaving insects. Thus, changing shiny black car painting to matt one is a disadvantageous fashion fad concerning the reduction of polarized light pollution of black vehicles. PMID:25076137
Clinical outcomes of black vs. non-black patients with locally advanced non-small cell lung cancer.
Vyfhuis, Melissa A L; Bhooshan, Neha; Molitoris, Jason; Bentzen, Søren M; Feliciano, Josephine; Edelman, Martin; Burrows, Whitney M; Nichols, Elizabeth M; Suntharalingam, Mohan; Donahue, James; Nagib, Marc; Carr, Shamus R; Friedberg, Joseph; Badiyan, Shahed; Simone, Charles B; Feigenberg, Steven J; Mohindra, Pranshu
2017-12-01
The black population remains underrepresented in clinical trials despite reports suggesting greater incidence and deaths from locally advanced non-small cell lung cancer (NSCLC). We determined outcomes for black and non-black patients in a well-annotated cohort treated with either definitive chemoradiation (CRT; bimodality) or CRT followed by surgery (trimodality therapy). A retrospective analysis of 355 stage III NSCLC patients treated with curative intent at the University of Maryland, Medical Center, between January 2000-December 2013 was performed. The Kaplan-Meier approach and the Cox proportional hazards models were used to analyze overall survival (OS) and freedom-from-recurrence (FFR) in black and non-black patients. The chi-square test was used to compare categorical variables. Black patients comprised 42% of the cohort and were more likely to be younger (p<0.0001), male (p=0.030), single (p<0.0001), reside in lower household income zipcodes (p<0.0001), have an Eastern Cooperative Oncology Group (ECOG) performance status >0 (p<0.001), and less likely to undergo surgery (p<0.0001). With a median follow-up of 15 months for all patients and 89 months for surviving patients (range:1-186 months), median OS times for black and non-black patients were 22 and 24 months, respectively (p=0.698). FFR rates were also comparable between the two groups (p=0.468). Surgery improved OS in both cohorts. Race was not a significant predictor for OS or FFR even when adjusted for other factors. We found similar oncologic outcomes in black and non-black NSCLC patients when treated with curative intent in a comprehensive cancer center setting, despite epidemiologic differences in presentation and receipt of care. Future efforts to improve outcomes in black patients could focus on addressing modifiable social disparities. Copyright © 2017. Published by Elsevier B.V.
Martin, R.E.; Leorri, E.; McLaughlin, P.P.
2007-01-01
Repeated marine invasions of the Black Sea during the Holocene have been inferred by many eastern scientists as resulting from episodes of marine inflow from the Mediterranean beneath a brackish outflow from the Black Sea. We support this scenario but a fundamental question remains: What caused the repeated marine invasions? We offer an hypothesis for the repeated marine invasions of the Black Sea based on: (1) the overall similarity of sea-level curves from both tectonically quiescent and active margins of the Black Sea and their similarity to a sequence stratigraphic record from the US mid-Atlantic coast. The similarity of the records from two widely-separated regions suggests their common response to documented Holocene climate ocean-atmosphere reorganizations (coolings); (2) the fact that in the modern Black Sea, freshwater runoff from surrounding rivers dominates over evaporation, so that excess runoff might have temporarily raised Black Sea level (although the Black Sea would have remained brackish). Following the initial invasion of the Black Sea by marine Mediterranean waters (through the Marmara Sea) in the early Holocene, repeated marine incursions were modulated, or perhaps even caused, by freshwater discharge to the Black Sea. Climatic amelioration (warming) following each documented ocean-atmosphere reorganization during the Holocene likely shifted precipitation patterns in the surrounding region and caused mountain glaciers to retreat, increasing freshwater runoff above modern values and temporarily contributing to an increase of Black Sea level. Freshwater-to-brackish water discharges into the Black Sea initially slowed marine inflow but upon mixing of runoff with more marine waters beneath them and their eventual exit through the Bosphorus, marine inflow increased again, accounting for the repeated marine invasions. The magnitude of the hydrologic and sea-level fluctuations became increasingly attenuated through the Holocene, as reflected by Black Sea level curves. ?? 2006 Elsevier Ltd and INQUA.
Lekavich, Carolyn L; Barksdale, Debra J
2016-01-01
In the United States, heart failure costs $34.4 billion annually and is associated with a mortality rate of 20% within 5 years of diagnosis. Heart failure preserved ejection fraction (HFpEF) accounts for 50% of all hospital admissions for heart failure. Black patients develop HFpEF at a significantly earlier age than do white patients, and the 5-year mortality rate for blacks with HFpEF is 30% to 44% higher compared with white patients. Current trials may not represent black patients proportionately to the general population. The primary aim of this literature review was to critically evaluate the representation of black patients in HFpEF trials and propose solutions for future research. PubMed and CINAHL were queried for peer-reviewed journal articles from 1997 to 2014 using 2 sets of search terms that included HFpEF or preserved left ventricular function and all relevant search terms for black patients. Initially, 182 articles were identified; however, after exclusionary criteria were applied, 22 articles remained. After critical review of each article for relevance, a total of 9 articles remained for the review. For the 9 trials reviewed including a total of 63,065 patients with HFpEF, 10,436 (17%) of the patients were black. Three of the 9 trials included less than 10% black patients, 4 trials included 10% to 20% black patients, and 2 trials included greater than 20% black patients. In 2 studies, the percentage of black patients in the HFpEF trial (13% and 17%) was significantly less than the percentage of black patients in the general regional population (53% and 39%), respectively. Although the mortality rate for black patients with HFpEF is 30% to 45% higher than the rate for white patients, 2 of the 9 studies did not have a representative sample of the general HFpEF population and none of the studies reported the objective of establishing a representative study population.
Blaho, Miklos; Herczeg, Tamas; Kriska, Gyorgy; Egri, Adam; Szaz, Denes; Farkas, Alexandra; Tarjanyi, Nikolett; Czinke, Laszlo; Barta, Andras; Horvath, Gabor
2014-01-01
The horizontally polarizing surface parts of shiny black cars (the reflection-polarization characteristics of which are similar to those of water surfaces) attract water-leaving polarotactic insects. Thus, shiny black cars are typical sources of polarized light pollution endangering water-leaving insects. A new fashion fad is to make car-bodies matt black or grey. Since rough (matt) surfaces depolarize the reflected light, one of the ways of reducing polarized light pollution is to make matt the concerned surface. Consequently, matt black/grey cars may not induce polarized light pollution, which would be an advantageous feature for environmental protection. To test this idea, we performed field experiments with horizontal shiny and matt black car-body surfaces laid on the ground. Using imaging polarimetry, in multiple-choice field experiments we investigated the attractiveness of these test surfaces to various water-leaving polarotactic insects and obtained the following results: (i) The attractiveness of black car-bodies to polarotactic insects depends in complex manner on the surface roughness (shiny, matt) and species (mayflies, dolichopodids, tabanids). (ii) Non-expectedly, the matt dark grey car finish is much more attractive to mayflies (being endangered and protected in many countries) than matt black finish. (iii) The polarized light pollution of shiny black cars usually cannot be reduced with the use of matt painting. On the basis of these, our two novel findings are that (a) matt car-paints are highly polarization reflecting, and (b) these matt paints are not suitable to repel polarotactic insects. Hence, the recent technology used to make matt the car-bodies cannot eliminate or even can enhance the attractiveness of black/grey cars to water-leaving insects. Thus, changing shiny black car painting to matt one is a disadvantageous fashion fad concerning the reduction of polarized light pollution of black vehicles.
Morii, Masahiro; Ideno, Takashi; Takemura, Kazuhisa; Okada, Mitsuhiro
2017-01-01
We aimed to identify the ways in which coloring cells affected decision-making in the context of binary-colored multi-attribute tables, using eye movement data. In our black-white attribute tables, the value of attributes was limited to two (with a certain threshold for each attribute) and each cell of the table was colored either black or white on the white background. We compared the two natural ways of systematic color assignment: “quantitatively coherent” ways and “qualitatively coherent” ways (namely, the ways in which the black-white distinction represented the quantitative amount distinction, and the ways in which the black-white distinction represented the quality distinction). The former consists of the following two types: (Type 1) “larger is black,” where the larger value-level was represented by black, and “smaller is white,” and (Type 2) “smaller is black.” The latter consisted of the following two types: (Type 3) “better is black,” and (Type 4) “worse is black.” We obtained the following two findings. [Result 1] The qualitatively coherent black-white tables (Types 3 and 4) made decision-making easier than the quantitatively coherent ones (Types 1 and 2). [Result 2] Among the two qualitatively coherent types, the “black is better” tables (Type 3) made decision making easier; in fact, the participants focused on the more important (black) cells in the case of “black is better” tables (Type 3) while they did not focus enough on the more important (white) ones in the case of the “white is better” tables (Type 4). We also examined some measures of eye movement patterns and showed that these measures supported our hypotheses. The data showed differences in the eye movement patterns between the first and second halves of each trial, which indicated the phased or combined decision strategies taken by the participants. PMID:28861020
77 FR 29621 - President's Board of Advisors on Historically Black Colleges and Universities
Federal Register 2010, 2011, 2012, 2013, 2014
2012-05-18
... (Secretary) on all matters pertaining to strengthening the educational capacity of Historically Black... DEPARTMENT OF EDUCATION President's Board of Advisors on Historically Black Colleges and Universities AGENCY: U.S. Department of Education, President's Board of Advisors on Historically Black Colleges...
77 FR 75120 - Black Hills National Forest Advisory Board
Federal Register 2010, 2011, 2012, 2013, 2014
2012-12-19
... DEPARTMENT OF AGRICULTURE Forest Service Black Hills National Forest Advisory Board AGENCY: Forest Service, USDA. ACTION: Notice of meeting. SUMMARY: The Black Hills National Forest Advisory Board will... copying. The public may inspect comments received at the Supervisor's Office, Black Hills National Forest...
76 FR 55368 - President's Board of Advisors on Historically Black Colleges and Universities
Federal Register 2010, 2011, 2012, 2013, 2014
2011-09-07
... all matters pertaining to strengthening the educational capacity of Historically Black Colleges and... DEARTMENT OF EDUCATION President's Board of Advisors on Historically Black Colleges and Universities AGENCY: U.S. Department of Education, President's Board of Advisors on Historically Black Colleges...
76 FR 7550 - President's Board of Advisors on Historically Black Colleges and Universities
Federal Register 2010, 2011, 2012, 2013, 2014
2011-02-10
... all matters pertaining to strengthening the educational capacity of Historically Black Colleges and... DEARTMENT OF EDUCATION President's Board of Advisors on Historically Black Colleges and Universities AGENCY: U.S. Department of Education, President's Board of Advisors on Historically Black Colleges...
The Media As Opiate: Blacks in the Performing Arts.
ERIC Educational Resources Information Center
Staples, Robert
1986-01-01
It is ironic that the barometer of progress for Blacks has been their success in the performing arts. The film industry has historically shaped and reflected racist attitudes toward Blacks, while the popular music industry still segregates and exploits Black artists. (Author/GC)
Black ice detection and road closure control system for Oklahoma.
DOT National Transportation Integrated Search
2014-10-01
Black ice is a thin coating of glazed ice on roadways or other transportation surfaces. Black : ice has identical appearance with black pavement and wet road, and it often forms during calm : weather. It is highly transparent and thus difficult to se...