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Sample records for anti-viral state segregates

  1. Anti-viral state segregates two molecular phenotypes of pancreatic adenocarcinoma: potential relevance for adenoviral gene therapy

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    Chiorini Jay A

    2010-01-01

    Full Text Available Abstract Background Pancreatic ductal adenocarcinoma (PDAC remains a leading cause of cancer mortality for which novel gene therapy approaches relying on tumor-tropic adenoviruses are being tested. Methods We obtained the global transcriptional profiling of primary PDAC using RNA from eight xenografted primary PDAC, three primary PDAC bulk tissues, three chronic pancreatitis and three normal pancreatic tissues. The Affymetrix GeneChip HG-U133A was used. The results of the expression profiles were validated applying immunohistochemical and western blot analysis on a set of 34 primary PDAC and 10 established PDAC cell lines. Permissivity to viral vectors used for gene therapy, Adenovirus 5 and Adeno-Associated Viruses 5 and 6, was assessed on PDAC cell lines. Results The analysis of the expression profiles allowed the identification of two clearly distinguishable phenotypes according to the expression of interferon-stimulated genes. The two phenotypes could be readily recognized by immunohistochemical detection of the Myxovirus-resistance A protein, whose expression reflects the activation of interferon dependent pathways. The two molecular phenotypes discovered in primary carcinomas were also observed among established pancreatic adenocarcinoma cell lines, suggesting that these phenotypes are an intrinsic characteristic of cancer cells independent of their interaction with the host's microenvironment. The two pancreatic cancer phenotypes are characterized by different permissivity to viral vectors used for gene therapy, as cell lines expressing interferon stimulated genes resisted to Adenovirus 5 mediated lysis in vitro. Similar results were observed when cells were transduced with Adeno-Associated Viruses 5 and 6. Conclusion Our study identified two molecular phenotypes of pancreatic cancer, characterized by a differential expression of interferon-stimulated genes and easily recognized by the expression of the Myxovirus-resistance A protein. We suggest that the detection of these two phenotypes might help the selection of patients enrolled in virally-mediated gene therapy trials.

  2. Anti-viral Responses in Insects

    Science.gov (United States)

    Although the study of anti-viral responses in insects has lagged behind studies of responses to other types of pathogens, progress has begun to rapidly accelerate over the past few years. Insects are subject to infection by many different kinds of DNA and RNA viruses. These include viruses that ar...

  3. Anti-viral RNA silencing: do we look like plants ?

    OpenAIRE

    Lecellier Charles-Henri; Saumet Anne

    2006-01-01

    Abstract The anti-viral function of RNA silencing was first discovered in plants as a natural manifestation of the artificial 'co-suppression', which refers to the extinction of endogenous gene induced by homologous transgene. Because silencing components are conserved among most, if not all, eukaryotes, the question rapidly arose as to determine whether this process fulfils anti-viral functions in animals, such as insects and mammals. It appears that, whereas the anti-viral process seems to ...

  4. Workplace Segregation in the United States: Race, Ethnicity, and Skill

    OpenAIRE

    Judith Hellerstein; David Neumark

    2005-01-01

    We study workplace segregation in the United States using a unique matched employer-employee data set that we have created. We present measures of workplace segregation by education and language, and by race and ethnicity, and ­ since skill is often correlated with race and ethnicity ­ we assess the role of education- and language-related skill differentials in generating workplace segregation by race and ethnicity. We define segregation based on the extent to which workers are more or less l...

  5. Autoimmune disease: A role for new anti-viral therapies?

    Science.gov (United States)

    Dreyfus, David H

    2011-12-01

    Many chronic human diseases may have an underlying autoimmune mechanism. In this review, the author presents a case of autoimmune CIU (chronic idiopathic urticaria) in stable remission after therapy with a retroviral integrase inhibitor, raltegravir (Isentress). Previous reports located using the search terms "autoimmunity" and "anti-viral" and related topics in the pubmed data-base are reviewed suggesting that novel anti-viral agents such as retroviral integrase inhibitors, gene silencing therapies and eventually vaccines may provide new options for anti-viral therapy of autoimmune diseases. Cited epidemiologic and experimental evidence suggests that increased replication of epigenomic viral pathogens such as Epstein-Barr Virus (EBV) in chronic human autoimmune diseases such as rheumatoid arthritis (RA), systemic lupus Erythematosus (SLE), and multiple sclerosis (MS) may activate endogenous human retroviruses (HERV) as a pathologic mechanism. Memory B cells are the reservoir of infection of EBV and also express endogenous retroviruses, thus depletion of memory b-lymphocytes by monoclonal antibodies (Rituximab) may have therapeutic anti-viral effects in addition to effects on B-lymphocyte presentation of both EBV and HERV superantigens. Other novel anti-viral therapies of chronic autoimmune diseases, such as retroviral integrase inhibitors, could be effective, although not without risk. PMID:21871974

  6. Anti-viral RNA silencing: do we look like plants ?

    Directory of Open Access Journals (Sweden)

    Lecellier Charles-Henri

    2006-01-01

    Full Text Available Abstract The anti-viral function of RNA silencing was first discovered in plants as a natural manifestation of the artificial 'co-suppression', which refers to the extinction of endogenous gene induced by homologous transgene. Because silencing components are conserved among most, if not all, eukaryotes, the question rapidly arose as to determine whether this process fulfils anti-viral functions in animals, such as insects and mammals. It appears that, whereas the anti-viral process seems to be similarly conserved from plants to insects, even in worms, RNA silencing does influence the replication of mammalian viruses but in a particular mode: micro(miRNAs, endogenous small RNAs naturally implicated in translational control, rather than virus-derived small interfering (siRNAs like in other organisms, are involved. In fact, these recent studies even suggest that RNA silencing may be beneficial for viral replication. Accordingly, several large DNA mammalian viruses have been shown to encode their own miRNAs. Here, we summarize the seminal studies that have implicated RNA silencing in viral infection and compare the different eukaryotic responses.

  7. Black Residential Segregation: Impact of State Licensing Laws.

    Science.gov (United States)

    Darden, Joe T.

    1982-01-01

    Compared the level of Black residential segregation among two groups of States: those whose real estate licensing laws contain explicit fair housing or anti-discrimination provisions, and those whose licensing laws contain no such provisions. Found that State licensing laws have no significant impact on Black residential discrimination. (GC)

  8. Total Synthesis and Anti-Viral Activities of an Extract of Radix isatidis

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    Li-Wei He

    2014-12-01

    Full Text Available Radix isatidis (Banlangen, a famous traditional Chinese medicine, has been used for thousands of years in China due to its anti-viral activity. Through our research, we inferred that the anti-viral activity of Radix isatidis depended on the water-soluble part. Among the components of this extract, the isoquinoline derivative 1 was isolated for the first time and has shown better anti-viral activity than other constituents. In this study, to solve the problem of sourcing sufficient quantities of compound 1, a total synthesis route is described, and several analogues are also evaluated for their anti-viral activities. Among them, compound 8 shown potent anti-viral activity with an IC50 value of 15.3 µg/mL. The results suggested that isoquinoline derivatives possessed potent anti-viral activity and are worthy further development.

  9. A murine model of coxsackievirus A16 infection for anti-viral evaluation.

    Science.gov (United States)

    Liu, Qingwei; Shi, Jinping; Huang, Xulin; Liu, Fei; Cai, Yicun; Lan, Ke; Huang, Zhong

    2014-05-01

    Coxsackievirus A16 (CA16) is one of the main causative agents of hand, foot and mouth disease (HFMD), which is a common infectious disease in children. CA16 infection may lead to severe nervous system damage and even death in humans. However, study of the pathogenesis of CA16 infection and development of vaccines and anti-viral agents are hindered partly by the lack of an appropriate small animal model. In the present study, we developed and characterized a murine model of CA16 infection. We show that neonatal mice are susceptible to CA16 infection via intraperitoneal inoculation. One-day-old mice infected with 2×10(6)TCID50 of CA16/SZ05 strain consistently exhibited clinical signs, including reduced mobility, and limb weakness and paralysis. About 57% of the mice died within 14days after infection. Significant damage in the brainstem, limb muscles and intestines of the infected mice in the moribund state was observed by histological examination, and the presence of CA16 in neurons of the brainstem was demonstrated by immunohistochemical staining with a CA16-specific polyclonal antibody, strongly suggesting the involvement of the central nervous system in CA16 infection. Analysis of virus titers in various organs/tissues collected at 3, 6 and 9days post-infection, showed that skeletal muscle was the major site of virus replication at the early stage of infection, while the virus mainly accumulated in the brain at the late stage. In addition, susceptibility of mice to CA16 infection was found to be age dependent. Moreover, different CA16 strains could exhibit varied virulence in vivo. Importantly, we demonstrated that post-exposure treatment with an anti-CA16 monoclonal antibody fully protected mice against lethal CA16 infection. Collectively, these results indicate the successful development of a CA16 infection mouse model for anti-viral evaluation. PMID:24583030

  10. Occupational Segregation by Race and Ethnicity in the US: Differences across States

    OpenAIRE

    Gradín, Carlos; del Río, Coral; Alonso-Villar, Olga

    2011-01-01

    Using the 2005–2007 American Community Survey, this paper analyzes the extent of geographical disparities in occupational segregation by race and ethnicity across the United States. Although the unconditional analysis shows great geographical variation in segregation, with the largest levels in the Southwest, the analysis of segregation conditioned on the distribution of characteristics reveals that segregation of workers with similar characteristics is generally greater in the East Central r...

  11. Residential Segregation in United States Cities: A Causal Analysis

    Science.gov (United States)

    Marshall, Harvey; Jiobu, Robert

    1975-01-01

    Using the technique of path analysis and cities as units of analysis, this study investigates the causes of black residential segregation. The data suggest that the relative socioeconomic status of blacks and black population size are important determinants of segregation. Also relevant are percent black and the relative growth rates of the white…

  12. "Brown" at 62: School Segregation by Race, Poverty and State

    Science.gov (United States)

    Orfield, Gary; Ee, Jongyeon; Frankenberg, Erica; Siegel-Hawley, Genevieve

    2016-01-01

    As the anniversary of "Brown v. Board of Education" decision arrives again without any major initiatives to mitigate spreading and deepening segregation in the nation's schools, the Civil Rights Project adds to a growing national discussion with a research brief drawn from a much broader study of school segregation to be published in…

  13. 77 FR 7600 - Notice of Segregation of Public Lands in the State of Arizona for the Restoration Design Energy...

    Science.gov (United States)

    2012-02-13

    ... Bureau of Land Management Notice of Segregation of Public Lands in the State of Arizona for the... this segregation total approximately 20,776 acres in Yuma County. DATES: This segregation is effective...: This segregation of public lands corresponds with the analysis of these same public lands as a...

  14. A single social defeat transiently suppresses the anti-viral immune response in mice

    OpenAIRE

    Groot, J.; van Milligen, FJ; Moonen-Leusen, BWM; Thomas, G.; KOOLHAAS, JM; van Milligen, Florine J.; Moonen-Leusen, Bernie W.M.; Koolhaas, Jaap M.

    1999-01-01

    Most of the studies dealing with effects of stress on anti-viral immunity have been carried out with stressors that are of long duration and that bear little relationship to the nature of the species. In this paper, we investigated the effect of a stressor mimicking real-life situations more closely, being social defeat of male mice, on anti-viral immunity. A single social defeat was applied at 3 or 6 days after inoculation with pseudorabies virus, a herpes virus. It appeared that lymph node ...

  15. Ethnic Residential Segregation by Nativity in Great Britain and the United States*

    OpenAIRE

    Iceland, John; Mateos, Pablo

    2011-01-01

    This study examines patterns of ethnic residential integration in Great Britain and the United States. Using data from 2000/2001 censuses from these two countries, we compute segregation indexes for comparably-defined ethnic groups by nativity and for specific foreign-born groups. We find that blacks are much less segregated in Great Britain than in the U.S, and black segregation patterns by nativity tend to be consistent with spatial assimilation in the former country (the foreign born are m...

  16. Modulation of heme oxygenase-1 by metalloporphyrins increases anti-viral T cell responses.

    Science.gov (United States)

    Bunse, C E; Fortmeier, V; Tischer, S; Zilian, E; Figueiredo, C; Witte, T; Blasczyk, R; Immenschuh, S; Eiz-Vesper, B

    2015-02-01

    Heme oxygenase (HO)-1, the inducible isoform of HO, has immunomodulatory functions and is considered a target for therapeutic interventions. In the present study, we investigated whether modulation of HO-1 might have regulatory effects on in-vitro T cell activation. The study examined whether: (i) HO-1 induction by cobalt-protoporphyrin (CoPP) or inhibition by tin-mesoporphyrin (SnMP) can affect expansion and function of virus-specific T cells, (ii) HO-1 modulation might have a functional effect on other cell populations mediating effects on proliferating T cells [e.g. dendritic cells (DCs), regulatory T cells (T(regs)) and natural killer cells] and (iii) HO-1-modulated anti-viral T cells might be suitable for adoptive immunotherapy. Inhibition of HO-1 via SnMP in cytomegalovirus (CMV)pp65-peptide-pulsed peripheral blood mononuclear cells (PBMCs) led to increased anti-viral T cell activation and the generation of a higher proportion of effector memory T cells (CD45RA(-) CD62L(-)) with increased capability to secrete interferon (IFN)-γ and granzyme B. T(reg) depletion and SnMP exposure increased the number of anti-viral T cells 15-fold. To test the possibility that HO-1 modulation might be clinically applicable in conformity with good manufacturing practice (GMP), SnMP was tested in isolated anti-viral T cells using the cytokine secretion assay. Compared to control, SnMP treatment resulted in higher cell counts and purity without negative impact on quality and effector function [CD107a, IFN-γ and tumour necrosis factor (TNF)-α levels were stable]. These results suggest an important role of HO-1 in the modulation of adaptive immune responses. HO-1 inhibition resulted in markedly more effective generation of functionally active T cells suitable for adoptive T cell therapy. PMID:25196646

  17. The anti-obesity drug orlistat reveals anti-viral activity.

    Science.gov (United States)

    Ammer, Elisabeth; Nietzsche, Sandor; Rien, Christian; Kühnl, Alexander; Mader, Theresa; Heller, Regine; Sauerbrei, Andreas; Henke, Andreas

    2015-12-01

    The administration of drugs to inhibit metabolic pathways not only reduces the risk of obesity-induced diseases in humans but may also hamper the replication of different viral pathogens. In order to investigate the value of the US Food and Drug Administration-approved anti-obesity drug orlistat in view of its anti-viral activity against different human-pathogenic viruses, several anti-viral studies, electron microscopy analyses as well as fatty acid uptake experiments were performed. The results indicate that administrations of non-cytotoxic concentrations of orlistat reduced the replication of coxsackievirus B3 (CVB3) in different cell types significantly. Moreover, orlistat revealed cell protective effects and modified the formation of multi-layered structures in CVB3-infected cells, which are necessary for viral replication. Lowering fatty acid uptake from the extracellular environment by phloretin administrations had only marginal impact on CVB3 replication. Finally, orlistat reduced also the replication of varicella-zoster virus moderately but had no significant influence on the replication of influenza A viruses. The data support further experiments into the value of orlistat as an inhibitor of the fatty acid synthase to develop new anti-viral compounds, which are based on the modulation of cellular metabolic pathways. PMID:25680890

  18. Latino residential segregation and self-rated health among Latinos: Washington State Behavioral Risk Factor Surveillance System, 2012-2014.

    Science.gov (United States)

    Plascak, Jesse J; Molina, Yamile; Wu-Georges, Samantha; Idris, Ayah; Thompson, Beti

    2016-06-01

    The relationship between Latino residential segregation and self-rated health (SRH) is unclear, but might be partially affected by social capital. We investigated the association between Latino residential segregation and SRH while also examining the roles of various social capital measures. Washington State Behavioral Risk Factor Surveillance System (2012-2014) and U.S. Census data were linked by zip code and zip code tabulation area. Multilevel logistic regression models were used to estimate odds of good or better SRH by Latino residential segregation, measured by the Gini coefficient, and controlling for sociodemographic, acculturation and social capital measures of neighborhood ties, collective socialization of children, and social control. The Latino residential segregation - SRH relationship was convex, or 'U'-shaped, such that increases in segregation among Latinos residing in lower segregation areas was associated with lower SRH while increases in segregation among Latinos residing in higher segregation areas was associated with higher SRH. The social capital measures were independently associated with SRH but had little effect on the relationship between Latino residential segregation and SRH. A convex relationship between Latino residential segregation and SRH could explain mixed findings of previous studies. Although important for SRH, social capital measures of neighborhood ties, collective socialization of children, and social control might not account for the relationship between Latino residential segregation and SRH. PMID:27173739

  19. Parties, Unions, Policies and Occupational Sex Segregation in the United States

    Science.gov (United States)

    Moller, Stephanie; Li, Huiping

    2009-01-01

    We utilize the 2000 Equal Employment Opportunity file of the U.S. Census and various secondary resources to determine if party control, union density and states' anti-discrimination and family leave policy legacies affect levels of occupational sex segregation across large counties. Our findings offer a puzzle to political sociologists because two…

  20. Budesonide and formoterol reduce early innate anti-viral immune responses in vitro.

    Directory of Open Access Journals (Sweden)

    Janet M Davies

    Full Text Available Asthma is a chronic inflammatory airways disease in which respiratory viral infections frequently trigger exacerbations. Current treatment of asthma with combinations of inhaled corticosteroids and long acting beta2 agonists improves asthma control and reduces exacerbations but what impact this might have on innate anti-viral immunity is unclear. We investigated the in vitro effects of asthma drugs on innate anti-viral immunity. Peripheral blood mononuclear cells (PBMC from healthy and asthmatic donors were cultured for 24 hours with the Toll-like receptor 7 agonist, imiquimod, or rhinovirus 16 (RV16 in the presence of budesonide and/or formoterol. Production of proinflammatory cytokines and expression of anti-viral intracellular signalling molecules were measured by ELISA and RT-PCR respectively. In PBMC from healthy donors, budesonide alone inhibited IP-10 and IL-6 production induced by imiquimod in a concentration-dependent manner and the degree of inhibition was amplified when budesonide and formoterol were used in combination. Formoterol alone had little effect on these parameters, except at high concentrations (10⁻⁶ M when IL-6 production increased. In RV16 stimulated PBMC, the combination of budesonide and formoterol inhibited IFNα and IP-10 production in asthmatic as well as healthy donors. Combination of budesonide and formoterol also inhibited RV16-stimulated expression of the type I IFN induced genes myxovirus protein A and 2', 5' oligoadenylate synthetise. Notably, RV16 stimulated lower levels of type Myxovirus A and oligoadenylate synthase in PBMC of asthmatics than control donors. These in vitro studies demonstrate that combinations of drugs commonly used in asthma therapy inhibit both early pro-inflammatory cytokines and key aspects of the type I IFN pathway. These findings suggest that budesonide and formoterol curtail excessive inflammation induced by rhinovirus infections in patients with asthma, but whether this inhibits

  1. The residential segregation of detailed Hispanic and Asian groups in the United States: 1980-2010

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    John Iceland

    2014-09-01

    Full Text Available Background: Racial and ethnic diversity continues to grow in communities across the United States,raising questions about the extent to which different ethnic groups will become residentially integrated. Objective: While a number of studies have examined the residential patterns of pan-ethnic groups, our goal is to examine the segregation of several Asian and Hispanic ethnic groups - Cubans, Dominicans, Mexicans, Puerto Ricans, Salvadorans, Asian Indians, Chinese, Filipinos, Japanese, Koreans, and Vietnamese. We gauge the segregation of each group from several alternative reference groups using two measures over the 1980 to 2010 period. Results: We find that the dissimilarity of Hispanics and Asians from other groups generally held steady or declined, though, because most Hispanic and Asian groups are growing, interaction with Whites also often declined. Our analyses also indicate that pan-ethnic segregation indexes do not always capture the experience of specific groups. Among Hispanics, Mexicans are typically less residentially segregated (as measured using the dissimilarity index from Whites, Blacks, Asians, and other Hispanics than are other Hispanic-origin groups. Among Asian ethnic groups, Japanese and Filipinos tend to have lower levels of dissimilarity from Whites, Blacks, and Hispanics than other Asian groups. Examining different dimensions of segregation also indicates that dissimilarity scores alone often do not capture to what extent various ethnic groups are actually sharing neighborhoods with each other. Finally, color lines vary across groups in some important ways, even as the dominant trend has been toward reduced racial and ethnic residential segregation over time. Conclusions: The overarching trend is that ethnic groups are becoming more residentially integrated,suggestive of assimilation, though there is significant variation across ethnic groups.

  2. Systems-Biology Approaches to Discover Anti-Viral Effectors of the Human Innate Immune Response

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    Andreas F.R. Sommer

    2011-07-01

    Full Text Available Virus infections elicit an immediate innate response involving antiviral factors. The activities of some of these factors are, in turn, blocked by viral countermeasures. The ensuing battle between the host and the viruses is crucial for determining whether the virus establishes a foothold and/or induces adaptive immune responses. A comprehensive systems-level understanding of the repertoire of anti-viral effectors in the context of these immediate virus-host responses would provide significant advantages in devising novel strategies to interfere with the initial establishment of infections. Recent efforts to identify cellular factors in a comprehensive and unbiased manner, using genome-wide siRNA screens and other systems biology “omics” methodologies, have revealed several potential anti-viral effectors for viruses like Human immunodeficiency virus type 1 (HIV-1, Hepatitis C virus (HCV, West Nile virus (WNV, and influenza virus. This review describes the discovery of novel viral restriction factors and discusses how the integration of different methods in systems biology can be used to more comprehensively identify the intimate interactions of viruses and the cellular innate resistance.

  3. Regulatory T cells control diabetes without compromising acute anti-viral defense☆

    Science.gov (United States)

    Sachithanantham, Sowbarnika; Dave, Amy; Rodriguez-Calvo, Teresa; Miller, Jacqueline; von Herrath, Matthias

    2016-01-01

    While previous reports have demonstrated the efficacy of regulatory T cell therapy in the prevention of diabetes, systemic immunocompromise and Treg instability remain key safety concerns. Here we examined the influence of induced Treg (iTreg) cell therapy on anti-viral host defense and autoimmune T cell responses during acute viral infection in a murine model of autoimmune diabetes. Protective transfers of iTregs maintained IL-10 expression, and expanded in vivo and controlled diabetes, despite losing FoxP3 expression. Adoptive transfer of iTregs affected neither the primary anti-viral CD8 T cell response nor viral clearance, although a significant and sustained suppression of CD4 T cell responses was observed. Following acute viral clearance, iTregs transferred early suppressed both CD4 and CD8 T cell responses, which resulted in the reversion of diabetes. These observations indicate that iTregs suppress local autoimmune processes while preserving the immunocompetent host's ability to combat acute viral infection. PMID:24858581

  4. Oral immune regulation: a novel method for modulation of anti-viral immunity.

    Science.gov (United States)

    Margalit, Maya; Ilan, Yaron

    2004-12-01

    Chronic viral infections, including hepatitis B and C and human immunodeficiency virus (HIV) infections, afflict a significant part of the world's population. In many of these diseases, chronicity has been linked to defective anti-viral immunity that damages host tissues without producing viral clearance. Currently available therapeutic measures for chronic viral infections are limited. Oral immune regulation, the manipulation of immune responses towards antigens by their oral administration, is a relatively simple and antigen-specific immune-modulatory tool. Recent evidence suggests that induction of oral immune-regulation towards viral antigens may entail a complex immune effect, characterized by simultaneous enhancement and suppression of different elements of the immune response in a manner that benefits the host. Such manipulation of the immune response towards viruses may achieve a combination of upregulated specific anti-viral immunity and inhibition of immune-mediated damage. Oral immune regulation may prove to be an important addition to the available therapeutic arsenal for chronic viral infections. PMID:15567096

  5. Autophagy is involved in anti-viral activity of pentagalloylglucose (PGG) against Herpes simplex virus type 1 infection in vitro

    International Nuclear Information System (INIS)

    Research highlights: → We showed PGG has anti-viral activity against Herpes simplex virus type 1 (HSV-1) and can induce autophgy. → Autophagy may be a novel and important mechanism mediating PGG anti-viral activities. → Inhibition of mTOR pathway is an important mechanism of induction of autophagy by PGG. -- Abstract: Pentagalloylglucose (PGG) is a natural polyphenolic compound with broad-spectrum anti-viral activity, however, the mechanisms underlying anti-viral activity remain undefined. In this study, we investigated the effects of PGG on anti-viral activity against Herpes simplex virus type 1 (HSV-1) associated with autophagy. We found that the PGG anti-HSV-1 activity was impaired significantly in MEF-atg7-/- cells (autophagy-defective cells) derived from an atg7-/- knockout mouse. Transmission electron microscopy revealed that PGG-induced autophagosomes engulfed HSV-1 virions. The mTOR signaling pathway, an essential pathway for the regulation of autophagy, was found to be suppressed following PGG treatment. Data presented in this report demonstrated for the first time that autophagy induced following PGG treatment contributed to its anti-HSV activity in vitro.

  6. 77 FR 12874 - Notice of Segregation of Public Lands in the State of Arizona Associated With the Proposed Mohave...

    Science.gov (United States)

    2012-03-02

    ... public scoping process for the Proposed Project on November 20, 2009 (74 FR 60289). A supplemental notice of intent was issued on July 26, 2010 (75 FR 43551). The BLM is segregating the lands under the... Bureau of Land Management Notice of Segregation of Public Lands in the State of Arizona Associated...

  7. Thermodynamic state functions of interfacial segregation and their role in the compensation effect

    Czech Academy of Sciences Publication Activity Database

    Lejček, Pavel; Hofmann, S.

    2009-01-01

    Roč. 21, č. 1 (2009), 27-34. ISSN 1606-5131 R&D Projects: GA ČR(CZ) GA202/06/0004; GA AV ČR KAN300100801 Institutional research plan: CEZ:AV0Z10100520 Keywords : thermodynamic state functions * segregation * compensation effect Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.558, year: 2009 http://www.ipme.ru/e-journals/RAMS/no_12109/contents.html

  8. Overcoming Triple Segregation

    Science.gov (United States)

    Gandara, Patricia

    2010-01-01

    Latinos are, after whites, the most segregated student group in the United States, and their segregation is closely tied to poor academic outcomes. Latinos experience a triple segregation: by race/ethnicity, poverty, and language. Racial segregation perpetuates negative stereotypes, reduces the likelihood of a strong teaching staff, and is often…

  9. Waste segregation

    International Nuclear Information System (INIS)

    A scoping study has been undertaken to determine the state-of-the-art of waste segregation technology as applied to the management of low-level waste (LLW). Present-day waste segregation practices were surveyed through a review of the recent literature and by means of personal interviews with personnel at selected facilities. Among the nuclear establishments surveyed were Department of Energy (DOE) laboratories and plants, nuclear fuel cycle plants, public and private laboratories, institutions, industrial plants, and DOE and commercially operated shallow land burial sites. These survey data were used to analyze the relationship between waste segregation practices and waste treatment/disposal processes, to assess the developmental needs for improved segregation technology, and to evaluate the costs and benefits associated with the implementation of waste segregation controls. This task was planned for completion in FY 1981. It should be noted that LLW management practices are now undergoing rapid change such that the technology and requirements for waste segregation in the near future may differ significantly from those of the present day. 8 figures

  10. Linear fidelity in quantification of anti-viral CD8+ T cells.

    Science.gov (United States)

    Flesch, Inge E A; Hollett, Natasha A; Wong, Yik Chun; Tscharke, David C

    2012-01-01

    Enumeration of anti-viral CD8(+) T cells to make comparisons between mice, viruses and vaccines is a frequently used approach, but controversy persists as to the most appropriate methods. Use of peptide-MHC tetramers (or variants) and intracellular staining for cytokines, in particular IFNγ, after a short ex vivo stimulation are now common, as are a variety of cytotoxicity assays, but few direct comparisons have been made. It has been argued that use of tetramers leads to the counting of non-functional T cells and that measurement of single cytokines will fail to identify cells with alternative functions. Further, the linear range of these methods has not been tested and this is required to give confidence that relative quantifications can be compared across samples. Here we show for two acute virus infections and CD8(+) T cells activated in vitro that DimerX (a tetramer variant) and intracellular staining for IFNγ, alone or in combination with CD107 to detect degranulation, gave comparable results at the peak of the response. Importantly, these methods were highly linear over nearly two orders of magnitude. In contrast, in vitro and in vivo assays for cytotoxicity were not linear, suffering from high background killing, plateaus in maximal killing and substantial underestimation of differences in magnitude of responses. PMID:22745779

  11. Linear fidelity in quantification of anti-viral CD8+ T cells.

    Directory of Open Access Journals (Sweden)

    Inge E A Flesch

    Full Text Available Enumeration of anti-viral CD8(+ T cells to make comparisons between mice, viruses and vaccines is a frequently used approach, but controversy persists as to the most appropriate methods. Use of peptide-MHC tetramers (or variants and intracellular staining for cytokines, in particular IFNγ, after a short ex vivo stimulation are now common, as are a variety of cytotoxicity assays, but few direct comparisons have been made. It has been argued that use of tetramers leads to the counting of non-functional T cells and that measurement of single cytokines will fail to identify cells with alternative functions. Further, the linear range of these methods has not been tested and this is required to give confidence that relative quantifications can be compared across samples. Here we show for two acute virus infections and CD8(+ T cells activated in vitro that DimerX (a tetramer variant and intracellular staining for IFNγ, alone or in combination with CD107 to detect degranulation, gave comparable results at the peak of the response. Importantly, these methods were highly linear over nearly two orders of magnitude. In contrast, in vitro and in vivo assays for cytotoxicity were not linear, suffering from high background killing, plateaus in maximal killing and substantial underestimation of differences in magnitude of responses.

  12. Reduction of resting state network segregation is linked to disorders of consciousness

    Science.gov (United States)

    Rudas, Jorge; Martínez, Darwin; Guaje, Javier; Demertzi, Athena; Heine, Lizette; Tshibanda, Luaba; Soddu, Andrea; Laureys, Steven; Gómez, Francisco

    2015-12-01

    Recent evidence suggests that healthy brain is organized on large-scale in regions spatially distant and partially temporally synchronized. These regions commonly are called Resting State Networks (RSNs). Many RSNs has been identified in multiples spatial scales in healthy subjects and their interactions has been used to define the functional network connectivity (FNC). The main idea in FNC is that the dynamic shown in the interactions among RSNs in control subjects, can change in pathological and pharmacological conditions. However, this hypothesis assumes that functional structure of healthy brain, remains in other brain states or conditions. In this work, we proposed a novel methodology in order to find the new brain functional structure for disorders of consciousness conditions, based on multi-objective optimization approach. Particularly, we find the best partition of RSNs set, that maximize two modularity measures (Kapur and Otsu measures). Our results suggest that the brain segregation level, may be linked to consciousness level.

  13. Dendritic cells and T cells deliver oncolytic reovirus for tumour killing despite pre-existing anti-viral immunity

    OpenAIRE

    Ilett, EJ; Prestwich, RJ; Kottke, T; Errington, F; Thompson, JM; Harrington, KJ; Pandha, HS; Coffey, M; Selby, PJ; Vile, RG; Melcher, AA

    2009-01-01

    Reovirus is a naturally occurring oncolytic virus currently in early clinical trials. However, the rapid induction of neutralizing antibodies represents a major obstacle to successful systemic delivery. This study addresses, for the first time, the ability of cellular carriers in the form of T cells and dendritic cells (DC) to protect reovirus from systemic neutralization. In addition, the ability of these cellular carriers to manipulate the subsequent balance of anti-viral versus anti-tumour...

  14. Genetically Engineered Protein Modules: Development and Applications in Anti-Viral Agent Screening and Cancer Marker Detection

    OpenAIRE

    Biswas, Payal

    2010-01-01

    ABSTRACT OF THE DISSERTATION Genetically Engineered Protein Modules: Development and Applications in Anti-Viral Agent Screening and Cancer Marker Detection byPayal BiswasDoctor of Philosophy Cell Molecular and Developmental Biology Graduate ProgramUniversity of California, Riverside, August 2010Dr. Wilfred Chen, ChairpersonOne of the most critical aspects in drug discovery is the bioactivity screening assay, by which compounds that most effectively inhibit the target are identified. During t...

  15. Contribution of Herpesvirus Specific CD8 T Cells to Anti-Viral T Cell Response in Humans

    OpenAIRE

    Elena Sandalova; Diletta Laccabue; Carolina Boni; Tan, Anthony T.; Katja Fink; Eng Eong Ooi; Robert Chua; Bahar Shafaeddin Schreve; Carlo Ferrari; Antonio Bertoletti

    2010-01-01

    Herpesviruses infect most humans. Their infections can be associated with pathological conditions and significant changes in T cell repertoire but evidences of symbiotic effects of herpesvirus latency have never been demonstrated. We tested the hypothesis that HCMV and EBV-specific CD8 T cells contribute to the heterologous anti-viral immune response. Volume of activated/proliferating virus-specific and total CD8 T cells was evaluated in 50 patients with acute viral infections: 20 with HBV, 1...

  16. The in vitro anti-viral potential of Setarud (IMOD™, a commercial herbal medicine with protective activity against acquired immune deficiency syndrome in clinical trials

    Directory of Open Access Journals (Sweden)

    Rezvan Zabihollahi

    2012-01-01

    Conclusions: Data from this study indicate that IMOD has significant anti-viral activity against HIV, HSV and MLV. Setarud could be subjected to further investigation after isolation of the constituents and determination of the toxic components.

  17. 77 FR 12873 - Notice of Segregation of Public Lands in the State of Arizona Associated With the Proposed...

    Science.gov (United States)

    2012-03-02

    ... (EIS) and initiated a public scoping process for the Proposed Project on January 14, 2010 (75 FR 2133... considered in conjunction with the ROW application for the Proposed Project (76 FR 17668). The BLM is... Bureau of Land Management Notice of Segregation of Public Lands in the State of Arizona Associated...

  18. 76 FR 38416 - Notice of Segregation of Public Lands in the States of Arizona, California, Colorado, Nevada, New...

    Science.gov (United States)

    2011-06-30

    ... Withdrawal and Opportunity for Public Meeting was published in the Federal Register (74 FR 31308), which... Register on April 21, 2011 (76 FR 22414). Michael D. Nedd, Assistant Director, Minerals and Realty... Bureau of Land Management Notice of Segregation of Public Lands in the States of Arizona,...

  19. The chemical bases of the various AIDS epidemics: recreational drugs, anti-viral chemotherapy and malnutrition

    Indian Academy of Sciences (India)

    Peter Duesberg; Claus Koehnlein; David Rasnick

    2003-06-01

    malnutrition, why they manifest in drug- and malnutrition-specific diseases, and why they are not self-limiting via anti-viral immunity. The hypothesis predicts AIDS prevention by adequate nutrition and abstaining from drugs, and even cures by treating AIDS diseases with proven medications.

  20. Residential Segregation and Birth Weight among Racial and Ethnic Minorities in the United States

    Science.gov (United States)

    Walton, Emily

    2009-01-01

    Racial and ethnic minorities are often residentially segregated from whites in urban settings, a fact which has important health consequences. Research on the relationship between residential segregation and health outcomes lacks national-level investigation of racial and ethnic minority groups other than African Americans. I use multilevel…

  1. Antibody-independent control of gamma-herpesvirus latency via B cell induction of anti-viral T cell responses.

    OpenAIRE

    Kelly B McClellan; Shivaprakash Gangappa; Speck, Samuel H.; Herbert W Virgin

    2006-01-01

    Synopsis B cells can control virus infection by making specific antibodies that bind to virus and infected cells. However, it is unknown whether B cells perform other anti-viral functions to protect the host during infection. The authors addressed this question by infecting mice with murine γ-herpesvirus 68 (γHV68), a relative of Epstein-Barr virus and Kaposi's sarcoma associated virus, which establishes lifelong latent infection in mice. Mice lacking B cells (B cell−/−) failed to control lat...

  2. Unsightly urban menaces and the rescaling of residential segregation in the United States.

    Science.gov (United States)

    Hanlon, James

    2011-01-01

    In this article, the author uses a slum clearance project in Lexington, Kentucky, as a lens through which to examine the spatial dynamics of racial residential segregation during the first half of the twentieth century. At the time, urban migration and upward socioeconomic mobility on the part of African Americans destabilized extant residential segregation patterns. Amid this instability, various spatial practices were employed in the interest of maintaining white social and economic supremacy. The author argues that such practices were indicative of a thoroughgoing reinvention of urban socio-spatial order that in turn precipitated the vastly expanded scale of residential segregation still found in U.S. cities today. Evidence of this reinvented ordering of urban space lies in the rendering of some long-standing African American neighborhoods as “out of place” within it and the use of slum clearance to remove the “menace” such neighborhoods posed to it. PMID:22073437

  3. Applied Thermodynamics: Grain Boundary Segregation

    OpenAIRE

    Pavel Lejček; Lei Zheng; Siegfried Hofmann; Mojmír Šob

    2014-01-01

    Chemical composition of interfaces—free surfaces and grain boundaries—is generally described by the Langmuir–McLean segregation isotherm controlled by Gibbs energy of segregation. Various components of the Gibbs energy of segregation, the standard and the excess ones as well as other thermodynamic state functions—enthalpy, entropy and volume—of interfacial segregation are derived and their physical meaning is elucidated. The importance of the thermodynamic state functions of grain boundary se...

  4. Small RNA profiling of Dengue virus-mosquito interactions implicates the PIWI RNA pathway in anti-viral defense

    Directory of Open Access Journals (Sweden)

    Olson Ken E

    2011-02-01

    Full Text Available Abstract Background Small RNA (sRNA regulatory pathways (SRRPs are important to anti-viral defence in mosquitoes. To identify critical features of the virus infection process in Dengue serotype 2 (DENV2-infected Ae. aegypti, we deep-sequenced small non-coding RNAs. Triplicate biological replicates were used so that rigorous statistical metrics could be applied. Results In addition to virus-derived siRNAs (20-23 nts previously reported for other arbovirus-infected mosquitoes, we show that PIWI pathway sRNAs (piRNAs (24-30 nts and unusually small RNAs (usRNAs (13-19 nts are produced in DENV-infected mosquitoes. We demonstrate that a major catalytic enzyme of the siRNA pathway, Argonaute 2 (Ago2, co-migrates with a ~1 megadalton complex in adults prior to bloodfeeding. sRNAs were cloned and sequenced from Ago2 immunoprecipitations. Viral sRNA patterns change over the course of infection. Host sRNAs were mapped to the published aedine transcriptome and subjected to analysis using edgeR (Bioconductor. We found that sRNA profiles are altered early in DENV2 infection, and mRNA targets from mitochondrial, transcription/translation, and transport functional categories are affected. Moreover, small non-coding RNAs (ncRNAs, such as tRNAs, spliceosomal U RNAs, and snoRNAs are highly enriched in DENV-infected samples at 2 and 4 dpi. Conclusions These data implicate the PIWI pathway in anti-viral defense. Changes to host sRNA profiles indicate that specific cellular processes are affected during DENV infection, such as mitochondrial function and ncRNA levels. Together, these data provide important progress in understanding the DENV2 infection process in Ae. aegypti.

  5. Changes in Workplace Segregation in the United States between 1990 and 2000: Evidence from Matched Employer-Employee Data

    OpenAIRE

    Judith Hellerstein; David Neumark; Melissa McInerney

    2007-01-01

    We present evidence on changes in workplace segregation by education, race, ethnicity, and sex, from 1990 to 2000. The evidence indicates that racial and ethnic segregation at the workplace level remained quite pervasive in 2000. At the same time, there was fairly substantial segregation by skill, as measured by education. Putting together the 1990 and 2000 data, we find no evidence of declines in workplace segregation by race and ethnicity; indeed, black-white segregation increased. Over thi...

  6. Do microRNAs induced by Viral Hemorrhagic Septicemia virus in rainbow trout (Oncorhynchus mykiss) possess anti-viral activity?

    DEFF Research Database (Denmark)

    Bela-Ong, Dennis; Schyth, Brian Dall; Lorenzen, Niels

    2013-01-01

    processes. Some miRNAs have been shown to have direct anti-viral effects. We have previously observed and validated that the fish-specific miRNAs, miR-462 and miR-731, were among the most highly expressed miRNAs in rainbow trout liver following Viral hemorrhagic septicemia virus (VHSV) infection. These mi...

  7. Agents of Change: Mixed-Race Households and the Dynamics of Neighborhood Segregation in the United States

    OpenAIRE

    Ellis, Mark; Holloway, Steven R.; Wright, Richard; Christopher S Fowler

    2011-01-01

    This article explores the effects of mixed-race household formation on trends in neighborhood-scale racial segregation. Census data show that these effects are nontrivial in relation to the magnitude of decadal changes in residential segregation. An agent-based model illustrates the potential long-run impacts of rising numbers of mixed-race households on measures of neighborhood-scale segregation. It reveals that high rates of mixed-race household formation will reduce residential segregation...

  8. Segregation Levels in Cleveland Public Schools and the Cleveland Voucher Program. School Choice Issues in the State

    Science.gov (United States)

    Forster, Greg

    2006-01-01

    Examining the widespread claims that private schools have high segregation levels and vouchers will lead to greater segregation, this study finds that both assertions are empirically unsupportable. Private schools participating in Cleveland's voucher program are much less segregated than Cleveland's public schools. This means that students using…

  9. The ISG15 conjugation system broadly targets newly synthesized proteins: implications for the anti-viral function of ISG15

    Science.gov (United States)

    Durfee, Larissa A.; Lyon, Nancy; Seo, Kyungwoon; Huibregtse, Jon M.

    2010-01-01

    Summary ISG15 is an interferon-induced and anti-viral ubiquitin-like protein (Ubl). Herc5, the major E3 enzyme for ISG15, mediates the ISGylation of over 300 proteins in interferon-stimulated cells. In addressing this broad substrate selectivity of Herc5, we found that: 1) the range of substrates extends even further and includes many exogenously expressed foreign proteins, 2) ISG15 conjugation is restricted to newly synthesized pools of proteins, and 3) Herc5 is physically associated with polyribosomes. These results lead to a model for ISGylation in which Herc5 broadly modifies newly synthesized proteins in a co-translational manner. This represents a novel mechanism for conjugation of a Ubl and further suggests that, in the context of an interferon-stimulated cell, newly translated viral proteins may be primary targets of ISG15. Consistent with this, we demonstrate that ISGylation of human papillomavirus (HPV) L1 capsid protein has a dominant-inhibitory effect on the infectivity of HPV16 pseudoviruses. PMID:20542004

  10. Antibody-independent control of gamma-herpesvirus latency via B cell induction of anti-viral T cell responses.

    Directory of Open Access Journals (Sweden)

    Kelly B McClellan

    2006-06-01

    Full Text Available B cells can use antibody-dependent mechanisms to control latent viral infections. It is unknown whether this represents the sole function of B cells during chronic viral infection. We report here that hen egg lysozyme (HEL-specific B cells can contribute to the control of murine gamma-herpesvirus 68 (gammaHV68 latency without producing anti-viral antibody. HEL-specific B cells normalized defects in T cell numbers and proliferation observed in B cell-/- mice during the early phase of gammaHV68 latency. HEL-specific B cells also reversed defects in CD8 and CD4 T cell cytokine production observed in B cell-/- mice, generating CD8 and CD4 T cells necessary for control of latency. Furthermore, HEL-specific B cells were able to present virally encoded antigen to CD8 T cells. Therefore, B cells have antibody independent functions, including antigen presentation, that are important for control of gamma-herpesvirus latency. Exploitation of this property of B cells may allow enhanced vaccine responses to chronic virus infection.

  11. Predicting polydisperse granular segregation

    OpenAIRE

    Isner, Austin; Schlick, Conor P.; Umbanhowar, Paul B.; Ottino, Julio M.; Lueptow, Richard M.

    2014-01-01

    Most granular materials in industrial applications and natural settings are size-polydisperse, but most models and simulations of segregation consider only bidisperse particle distributions. Here, we extend our recently developed theoretical advection–diffusion–segregation model to polydisperse particle distributions. To test the theoretical approach, we model and simulate grains log-normally distributed by size in a chute flow. In steady state, material near the free surface is dominated by ...

  12. The design and synthesis of novel N-heterocyclic compounds, and their evaluation of anti-cancer and anti-viral activity

    OpenAIRE

    More, Vijaykumar

    2014-01-01

    2010 - 2011 The thesis entitled “The design and synthesis of novel N-heterocyclic compounds, and their evaluation of anti-cancer and anti-viral activity" is divided into three chapters. The title of the thesis clearly reflects the importance of nitrogen heterocycles compounds: in fact they are extremely pivotal structural motifs responsible for eliciting various biological activities in natural products and synthetic medicines. This has attracted the medicinal chemists towards the synth...

  13. Resveratrol production in bioreactor: Assessment of cell physiological states and plasmid segregational stability

    Directory of Open Access Journals (Sweden)

    Margarida S. Afonso

    2015-03-01

    Full Text Available Resveratrol is a plant secondary metabolite commonly found in peanuts and grapevines with significant health benefits. Recombinant organisms can produce large amounts of resveratrol and, in this work, Escherichia coli BW27784 was used to produce resveratrol in bioreactors while monitoring cell physiology and plasmid stability through flow cytometry and real-time qPCR, respectively. Initially, the influence of culture conditions and precursor addition was evaluated in screening assays and the data gathered was used to perform the bioreactor assays, allowing the production of 160 μg/mL of resveratrol. Cellular physiology and plasmid instability affected the final resveratrol production, with lower viability and plasmid copy numbers associated with lower yields. In sum, this study describes new tools to monitor the bioprocess, evaluating the effect of culture conditions, and its correlation with cell physiology and plasmid segregational stability, in order to define a viable and scalable bioprocess to fulfill the need for larger quantities of resveratrol.

  14. Measuring Segregation

    OpenAIRE

    David M. Frankel; Oscar Volij

    2004-01-01

    We propose a set of axioms for the measurement of multigroup school segregation. They are motivated by two criteria: do ethnic groups have similar distributions across schools? And are schools ethnically representative of their district? Our axioms are satisfied by a unique ordering. It is represented by the Mutual Information index. This index, originally proposed by Henri Theil, has a more intuitive decomposition than other indices. As an application, we find that segregation between distri...

  15. Education Dept. to Use 1992 Supreme Court Case in Judging Formerly Segregated State Systems.

    Science.gov (United States)

    Jaschik, Scott

    1994-01-01

    The Department of Education's announcement of new policy concerning the evaluation of college desegregation efforts could affect the monitoring of compliance in several states in which court-ordered desegregation plans have expired. The higher standards are based on the 1992 Supreme Court ruling, United States v. Fordice. (MSE)

  16. Segregation Levels in Milwaukee Public Schools and the Milwaukee Voucher Program. School Choice Issues in the State

    Science.gov (United States)

    Forster, Greg

    2006-01-01

    This study compares segregation levels in Milwaukee public schools and in private schools participating in the Milwaukee voucher program. Using a segregation index that measures the difference between the percent of students in a school who are white and the percentage of school-age children in the greater metro area who are white, it finds that…

  17. School Segregation, Residential Segregation: Some Speculation.

    Science.gov (United States)

    Kantrowitz, Nathan

    This essay addressed the question of to what extent does school segregation and school desegregation policy shape residential segregation. Census data, ethnic segregation, voluntary self-segregation, and attitude surveys are discussed in the residential segregation section. The Wolf and Lebeaux study is critically appraised in reference to school…

  18. Exploring the Landscape of Inclusion: Profiles of Inclusive versus Segregated School Districts in the United States

    Science.gov (United States)

    Marks, Susan Unok; Kurth, Jennifer A.; Bartz, Jody Marie

    2014-01-01

    Although inclusive education has been increasing in frequency for students with disabilities in the United States, for many students, the opportunity to be educated with their peers without disabilities continues to be out of reach despite decades of efforts by those promoting the vision of inclusion. This exploratory case study used interviews…

  19. From Segregation to School Finance: The Legal Context for Language Rights in the United States

    Science.gov (United States)

    Powers, Jeanne M.

    2014-01-01

    In this chapter, the author reviews the legal trajectory of language rights in public schooling in the United States and how language has been intertwined with other policy issues in court cases aimed at expanding access and equity for minority students: desegregation and school finance. Most of these cases originated in the Southwestern United…

  20. New York State's Extreme School Segregation: Inequality, Inaction and a Damaged Future

    Science.gov (United States)

    Kucsera, John

    2014-01-01

    The fight for equal educational opportunity in New York has followed a pattern similar to other diverse or racially transforming states. From the 1950s to 1980s, the issue of school desegregation was an important issue. Local civil rights pressure, the courts, and legislation attempted to desegregate large urban school systems through both…

  1. Residentielle Segregation

    OpenAIRE

    Dangschat, Jens S.

    2014-01-01

    "Die residentielle Segregation - verstanden als die ungleichmäßige Verteilung der Wohngelegenheiten sozialer Gruppen - wird über Segregationsindices als relative Abweichung der Anteilswerte in städtischen Teilgebieten gegenüber der Gesamtstadt gemessen. Diese Durchschnittswerte sagen jedoch nichts darüber aus, ob es in einer städtischen Agglomeration 'problematische' sozialräumliche Konstellationen gibt, sie haben daher keinen kommunalpolitischen oder stadtentwicklungsplanerischen Wert. Zudem...

  2. Surface Segregation in YSZ

    DEFF Research Database (Denmark)

    Bay, Lasse; Zachau-Christiansen, Birgit; Jacobsen, Torben

    1998-01-01

    The space charge layer formed due to segregation of yttria and oxygen ion vacancies in YSZ is described by a simple model. Effects of impurities segregation are omitted.......The space charge layer formed due to segregation of yttria and oxygen ion vacancies in YSZ is described by a simple model. Effects of impurities segregation are omitted....

  3. Risk of Severe Acute Exacerbation of Chronic HBV Infection Cancer Patients Who Underwent Chemotherapy and Did Not Receive Anti-Viral Prophylaxis.

    Directory of Open Access Journals (Sweden)

    Chih-An Shih

    Full Text Available Reactivation of HBV replication with an increase in serum HBV DNA and alanine aminotransferase (ALT activity has been reported in 20-50% of hepatitis B carriers undergoing cytotoxic chemotherapy for cancer treatment. Manifestation of HBV reactivation ranges from asymptomatic self-limiting hepatitis to severe progressive hepatic failure and fatal consequences.To investigate the risk of severe acute exacerbation of chronic HBV infection in HBsAg-positive cancer patients with solid tumors or hematological malignancies who underwent chemotherapy without antiviral prophylaxis.A retrospective review of charts was conducted for HBsAg-positive cancer patients in our institution who underwent chemotherapy and did not receive anti-viral prophylaxis between the periods of July 2007 to January 2013. We investigate the incidence of severe acute exacerbation of chronic HBV infection if these patients with a variety of solid tumors and hematological malignancies.A total of 156 patients (hematological malignancies: 16; solid tumors: 140 were included. The incidence of severe acute HBV exacerbation in the patients with hematological malignancy was higher than that in solid tumors (25.0% [4/16] vs 4.3% [6/140]; P = 0.005. Additionally, patients receiving rituximab-based chemotherapy had higher acute exacerbation rate than those with non-rituximab-based chemotherapy (40.0% vs 4.1%, P = 0.001. Among the patients with solid tumors, the incidences of severe acute exacerbation of chronic HBV in hepatocellular carcinoma, colorectal cancer, lung cancer, breast cancer, gynecological cancer, urological tract cancer, head/neck cancer and other solid malignancies were 2.3%, 4.0%, 7.1%, 9.0%, 16.7%, 6.7%, 0% and 0%, respectively.Severe acute exacerbation of chronic HBV infection may occur in HBsAg-positive patients with a variety of solid tumors who received chemotherapy without adequate anti-viral prophylaxis. Hematological malignancy and rituximab-based chemotherapy are

  4. Induction of anti-viral genes during acute infection with Viral hemorrhagic septicemia virus (VHSV) genogroup IVa in Pacific herring (Clupea pallasii)

    Science.gov (United States)

    Hansen, John D.; Woodson, James C.; Hershberger, Paul K.; Grady, Courtney; Gregg, Jacob L.; Purcell, Maureen K.

    2012-01-01

    Infection with the aquatic rhabdovirus Viral hemorrhagic septicemia virus (VHSV) genogroup IVa results in high mortality in Pacific herring (Clupea pallasii) and is hypothesized to be a potential limiting factor for herring recovery. To investigate anti-viral immunity in the Pacific herring, four immune response genes were identified: the myxovirus resistance (Clpa-Mx), a major histocompatibility complex IB (named Clpa-UAA.001), the inducible immunoproteosome subunit 9 (Clpa-PSMB9) and the neutrophil chemotactic factor (Clpa-LECT2). Reverse transcriptase quantitative PCR (RT-qPCR) assays were developed based on these gene sequences to investigate the host immune response to acute VHSV infection following both injection and immersion challenge. Virus levels were measured by both plaque assay and RT-qPCR and peaked at day 6 during the 10-day exposure period for both groups of fish. The interferon stimulated genes (Clpa-Mx, −UAA.001, and −PSMB9) were significantly up-regulated in response to VHSV infection at both 6 and 10 days post-infection in both spleen and fin. Results from this study indicate that Pacific herring mount a robust, early antiviral response in both fin and spleen tissues. The immunological tools developed in this study will be useful for future studies to investigate antiviral immunity in Pacific herring.

  5. A forward-genetic screen and dynamic analysis of lambda phage host-dependencies reveals an extensive interaction network and a new anti-viral strategy.

    Directory of Open Access Journals (Sweden)

    Nathaniel D Maynard

    2010-07-01

    Full Text Available Latently infecting viruses are an important class of virus that plays a key role in viral evolution and human health. Here we report a genome-scale forward-genetics screen for host-dependencies of the latently-infecting bacteriophage lambda. This screen identified 57 Escherichia coli (E. coli genes--over half of which have not been previously associated with infection--that when knocked out inhibited lambda phage's ability to replicate. Our results demonstrate a highly integrated network between lambda and its host, in striking contrast to the results from a similar screen using the lytic-only infecting T7 virus. We then measured the growth of E. coli under normal and infected conditions, using wild-type and knockout strains deficient in one of the identified host genes, and found that genes from the same pathway often exhibited similar growth dynamics. This observation, combined with further computational and experimental analysis, led us to identify a previously unannotated gene, yneJ, as a novel regulator of lamB gene expression. A surprising result of this work was the identification of two highly conserved pathways involved in tRNA thiolation-one pathway is required for efficient lambda replication, while the other has anti-viral properties inhibiting lambda replication. Based on our data, it appears that 2-thiouridine modification of tRNAGlu, tRNAGln, and tRNALys is particularly important for the efficient production of infectious lambda phage particles.

  6. 1990 Sir Henry Wellcome medal and prize winner. Leukoregulin: a new biotherapeutic cytokine in the search for more effective anti-viral pharmacologic agents.

    Science.gov (United States)

    Evans, C H; Hooks, J J; Detrick, B

    1991-04-01

    This investigation examines whether cytokines, as exemplified by leukoregulin, with their immense potential for biorecognition and target cell modulation as a result of their complex three-dimensional structure, have the potential to provide new directions for biotherapy of infectious disease. Leukoregulin is a naturally occurring immunologic cytokine, secreted by stimulated lymphocytes, which increases membrane permeability and drug uptake in tumor but not in normal cells. This study demonstrates that leukoregulin also increases the plasma membrane permeability of cells acutely infected with herpes simplex type 1 virus and that the increase in membrane permeability is accompanied by a 10- to 100-fold increase in the ability of acyclovir to inhibit the release of infectious virus when the cells are treated with leukoregulin 3 hours after infection with the virus. This is the first demonstration that a cytokine, alone or in combination with anti-viral chemotherapy, can effectively inhibit virus replication in human cells following acute virus infection, which indicates that combination immunotherapy and chemotherapy have the potential to completely inhibit the production of infectious virus by acutely infected human cells. PMID:1851546

  7. Poisson Indices of Segregation

    OpenAIRE

    Angelo, Mele

    2009-01-01

    Existing indices of residential segregation are based on an arbitrary partition of the city in neighborhoods: given a spatial distribution of racial groups, the index provides different levels of segregation for different partitions. This paper proposes a method in which individual locations are mapped to aggregate levels of segregation, avoiding arbitrary partitions. Assuming a simple spatial process driving the locations of different racial groups, I define a location-specific segregation i...

  8. Segregation of face sensitive areas within the fusiform gyrus using global signal regression? A study on amygdala resting-state functional connectivity.

    Science.gov (United States)

    Kruschwitz, Johann D; Meyer-Lindenberg, Andreas; Veer, Ilya M; Wackerhagen, Carolin; Erk, Susanne; Mohnke, Sebastian; Pöhland, Lydia; Haddad, Leila; Grimm, Oliver; Tost, Heike; Romanczuk-Seiferth, Nina; Heinz, Andreas; Walter, Martin; Walter, Henrik

    2015-10-01

    The application of global signal regression (GSR) to resting-state functional magnetic resonance imaging data and its usefulness is a widely discussed topic. In this article, we report an observation of segregated distribution of amygdala resting-state functional connectivity (rs-FC) within the fusiform gyrus (FFG) as an effect of GSR in a multi-center-sample of 276 healthy subjects. Specifically, we observed that amygdala rs-FC was distributed within the FFG as distinct anterior versus posterior clusters delineated by positive versus negative rs-FC polarity when GSR was performed. To characterize this effect in more detail, post hoc analyses revealed the following: first, direct overlays of task-functional magnetic resonance imaging derived face sensitive areas and clusters of positive versus negative amygdala rs-FC showed that the positive amygdala rs-FC cluster corresponded best with the fusiform face area, whereas the occipital face area corresponded to the negative amygdala rs-FC cluster. Second, as expected from a hierarchical face perception model, these amygdala rs-FC defined clusters showed differential rs-FC with other regions of the visual stream. Third, dynamic connectivity analyses revealed that these amygdala rs-FC defined clusters also differed in their rs-FC variance across time to the amygdala. Furthermore, subsample analyses of three independent research sites confirmed reliability of the effect of GSR, as revealed by similar patterns of distinct amygdala rs-FC polarity within the FFG. In this article, we discuss the potential of GSR to segregate face sensitive areas within the FFG and furthermore discuss how our results may relate to the functional organization of the face-perception circuit. PMID:26178527

  9. Nonmetropolitan Residential Segregation Revisited.

    Science.gov (United States)

    Murdock, Steve H.; And Others

    1994-01-01

    Analysis of 1980 and 1990 Censuses of Population and Housing for Texas found overall black-white and Anglo-Hispanic residential segregation declined substantially. Nonmetropolitan counties were more segregated than metropolitan counties in both years, but growing nonmetro places showed the greatest segregation declines. Analyses controlling for…

  10. Why Our Schools Are Segregated

    Science.gov (United States)

    Rothstein, Richard

    2013-01-01

    "Residential segregation's causes are both knowable and known," writes Richard Rothstein. According to Rothstein, those causes are "20th century federal, state, and local policies explicitly designed to separate the races." Even seasoned policymakers are convinced that the residential isolation of low-income black children…

  11. Gender Segregation: Separate but Effective?

    Science.gov (United States)

    Holthouse, David

    2010-01-01

    In 2002, only 11 public schools in the United States had gender-segregated classrooms. As of December 2009, there were more than 550. The movement is based on the hypothesis that hard-wired differences in the ways that male and female brains develop and function in childhood through adolescence require classrooms in which boys and girls are not…

  12. Revisiting Residential Segregation by Income: A Monte Carlo Test

    OpenAIRE

    Junfu Zhang

    2003-01-01

    A long-standing hypothesis states that racial housing segregation in the U.S. results from the income inequalities between blacks and whites. This paper reexamines this hypothesis with a new methodology. We present a Monte Carlo study to show that segregation by income explains only a small proportion of the high level of segregation.

  13. 26 CFR 301.7507-3 - Segregated or transferred assets.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 18 2010-04-01 2010-04-01 false Segregated or transferred assets. 301.7507-3... States § 301.7507-3 Segregated or transferred assets. (a) In general. In a case involving segregated or transferred assets, it is not necessary, for application of section 7507, that the assets shall...

  14. Segregation in Vertically Vibrated Binary Granular Mixtures with Same Size

    Institute of Scientific and Technical Information of China (English)

    SHI Qing-Fan; SUN Gang; HOU Mei-Ying; LU Kun-Quan

    2006-01-01

    @@ Segregation in vertically vibrated binary granular mixtures with same size is studied experimentally. A new partial segregated state is found in this system. This state exists between the completely mixed state and the pure segregated state, and has the characteristic that the lighter particles tend to rise and form a pure layer on the top of the system while the heavier particles and some of the lighter ones stay at the bottom and form a mixed layer.

  15. Local versus overall segregation measures

    OpenAIRE

    Olga Alonso-Villar; Coral del Río

    2008-01-01

    This paper proposes a framework in which to study the segregation of a target group in a multigroup context, according either to an evenness perception or to a representativeness view of segregation, and offers a bridge between local segregation and overall segregation. In doing so, this paper first presents an axiomatic set-up within which local segregation measures can be evaluated, and defines local segregation curves. Next, a class of additive segregation indexes, related to the generaliz...

  16. On the Measurement of Segregation

    OpenAIRE

    Federico Echenique; Roland G. Fryer, Jr.

    2005-01-01

    This paper develops a measure of segregation based on two premises: (1) a measure of segregation should disaggregate to the level of individuals, and (2) an individual is more segregated the more segregated are the agents with whom she interacts. Developing three desirable axioms that any segregation measure should satisfy, we prove that one and only one segregation index satisfies our three axioms, and the two aims mentioned above; which we coin the Spectral Segregation Index. We apply the i...

  17. Measuring School Segregation

    OpenAIRE

    David M. Frankel; Volij, Oscar

    2011-01-01

    Using only ordinal axioms, we characterize several multi-group school segregation indices: the Atkinson Indices for the class of school districts with a given fixed number of ethnic groups and the Mutual Information Index for the class of all districts. Properties of other school segregation indices are also discussed. In an empirical application, we document a weakening of the effect of ethnicity on school assignment from 1987/8 to 2007/8. We also show that segregation between districts with...

  18. 78 FR 53779 - Notice To Extend Mineral Segregation for the Proposed Silver State Solar Project Near Primm in...

    Science.gov (United States)

    2013-08-30

    ... solar energy project would consist of photovoltaic panels and related ROW appurtenances, including a... the development of valuable renewable energy resources and to avoid conflicts between renewable energy... Energy Project Manager, at 702-515-5173; or email at SilverStateSouthEIS@blm.gov . Persons who use...

  19. Granular size segregation in underwater sand ripples.

    Science.gov (United States)

    Rousseaux, G; Caps, H; Wesfreid, J-E

    2004-02-01

    We report an experimental study of a binary sand bed under an oscillating water flow. The formation and evolution of ripples is observed. The appearance of a granular segregation is shown to strongly depend on the sand bed preparation. The initial wavelength of the mixture is measured. In the final steady state, a segregation in volume is observed instead of a segregation at the surface as reported before. The correlation between this phenomenon and the fluid flow is emphasised. Finally, different "exotic" patterns and their geophysical implications are presented. PMID:15052430

  20. Anti-viral properties and mode of action of standardized Echinacea purpurea extract against highly pathogenic avian Influenza virus (H5N1, H7N7 and swine-origin H1N1 (S-OIV

    Directory of Open Access Journals (Sweden)

    Schoop Roland

    2009-11-01

    Full Text Available Abstract Background Influenza virus (IV infections are a major threat to human welfare and animal health worldwide. Anti-viral therapy includes vaccines and a few anti-viral drugs. However vaccines are not always available in time, as demonstrated by the emergence of the new 2009 H1N1-type pandemic strain of swine origin (S-OIV in April 2009, and the acquisition of resistance to neuraminidase inhibitors such as Tamiflu® (oseltamivir is a potential problem. Therefore the prospects for the control of IV by existing anti-viral drugs are limited. As an alternative approach to the common anti-virals we studied in more detail a commercial standardized extract of the widely used herb Echinacea purpurea (Echinaforce®, EF in order to elucidate the nature of its anti-IV activity. Results Human H1N1-type IV, highly pathogenic avian IV (HPAIV of the H5- and H7-types, as well as swine origin IV (S-OIV, H1N1, were all inactivated in cell culture assays by the EF preparation at concentrations ranging from the recommended dose for oral consumption to several orders of magnitude lower. Detailed studies with the H5N1 HPAIV strain indicated that direct contact between EF and virus was required, prior to infection, in order to obtain maximum inhibition in virus replication. Hemagglutination assays showed that the extract inhibited the receptor binding activity of the virus, suggesting that the extract interferes with the viral entry into cells. In sequential passage studies under treatment in cell culture with the H5N1 virus no EF-resistant variants emerged, in contrast to Tamiflu®, which produced resistant viruses upon passaging. Furthermore, the Tamiflu®-resistant virus was just as susceptible to EF as the wild type virus. Conclusion As a result of these investigations, we believe that this standard Echinacea preparation, used at the recommended dose for oral consumption, could be a useful, readily available and affordable addition to existing control options

  1. Segregation and Civic Virtue

    Science.gov (United States)

    Merry, Michael S.

    2012-01-01

    In this essay Michael Merry defends the following prima facie argument: that civic virtue is not dependent on integration and in fact may be best fostered under conditions of segregation. He demonstrates that civic virtue can and does take place under conditions of involuntary segregation, but that voluntary separation--as a response to…

  2. Neighborhood Schools and Racial Segregation

    Science.gov (United States)

    Kelleher, Daniel T.

    1975-01-01

    Neighborhood school concept and racially segregated residential patterns account for most of the segregation in American public schools today. The focus of this article will be to explain the reasons for residential segregation. (Author/RK)

  3. Urban vegetation and income segregation in drylands: a synthesis of seven metropolitan regions in the southwestern United States

    International Nuclear Information System (INIS)

    To better understand how urbanization affects the amount and timing of urban vegetation in drylands we investigated remotely sensed vegetation patterns across seven large metropolitan regions in the southwestern United States. We asked (1) how low density urban land cover differed from adjacent wildland grass, herb, and shrub land covers in both the amount of vegetation and the length of the growing season, (2) how neighborhood income affected patterns of vegetation within low density urban cover, and (3) how cities differed from one another in their vegetation patterns. We found that urbanization generally has a strong influence on vegetation compared to adjacent wildlands. In four of the metropolitan regions the cumulative enhanced vegetation index (EVI) and growing season length in low density developments were higher than grass, herb, and shrub land covers. Within all metropolitan regions, there was a significant socioeconomic effect where higher income areas had a higher cumulative EVI than lower income areas. The large differences in urban vegetation among cities were related to precipitation and total domestic water use. These findings help to identify how urbanization influences vegetation, with implications for the availability of ecosystem services and requirements for irrigation in hot dryland cities. (letter)

  4. Plasmid segregation mechanisms

    DEFF Research Database (Denmark)

    Ebersbach, Gitte; Gerdes, Kenn; Charbon, Gitte Ebersbach

    2005-01-01

    Bacterial plasmids encode partitioning (par) loci that ensure ordered plasmid segregation prior to cell division. par loci come in two types: those that encode actin-like ATPases and those that encode deviant Walker-type ATPases. ParM, the actin-like ATPase of plasmid R1, forms dynamic filaments...... that segregate plasmids paired at mid-cell to daughter cells. Like microtubules, ParM filaments exhibit dynamic instability (i.e., catastrophic decay) whose regulation is an important component of the DNA segregation process. The Walker box ParA ATPases are related to MinD and form highly dynamic, oscillating...... filaments that are required for the subcellular movement and positioning of plasmids. The role of the observed ATPase oscillation is not yet understood. However, we propose a simple model that couples plasmid segregation to ParA oscillation. The model is consistent with the observed movement...

  5. Segregation by friction

    OpenAIRE

    Kondic, L.; Hartley, R. R.; Tennakoon, S. G. K.; Painter, B; Behringer, R. P.

    2002-01-01

    Granular materials are known to separate by size under a variety of circumstances. Experiments presented here and elucidated by modeling and MD simulation document a new segregation mechanism, namely segregation by friction. The experiments are carried out by placing steel spheres on a horizontal plane enclosed by rectangular sidewalls, and subjecting them to horizontal shaking. Half the spheres are highly smooth; the remainder are identical to the first half, except that their surfaces have ...

  6. Gender-based Segregation before and after the Great Recession

    OpenAIRE

    Stephan HUMPERT

    2015-01-01

    Pooled international survey data is used to analyze occupational segregation in times of the great recession. Observing over 30 European economies and the United States over a time span of 10 years, I present evidence of a somehow surprising crisis effect on gender-based segregation. While all economies differ in their general magnitudes, the economic downturn affects a temporary reduction of segregation in terms of two dissimilarity measures.

  7. Residential Segregation of Socioeconomic Variables and Health Indices in Iran

    OpenAIRE

    Seyed Saeed Hashemi Nazari; Mahmood Mahmoodi; Kourosh Holakouie Naieni

    2013-01-01

    Background: Measures of segregation are essential tools for evaluation of social equality. They describe complex structural patterns by single quantities and allow the comparison of inequalities over time or between residential places. In many countries, patterns of residential segregation are well described (e.g., South Africa, Great Britain, United States of America). In this study, for the first time in Iran, we measured residential segregation for some socioeconomic and health variables a...

  8. Understanding Segregation Processes

    Science.gov (United States)

    Bruch, Elizabeth

    There is growing consensus that living in neighborhoods of concentrated poverty increases the likelihood of social problems such as teenage parenthood, drug and alcohol use, crime victimization, and chronic unemployment. Neighborhood inequality is also implicated in studies of enduring race/ethnic health disparities, and there are recent moves to broaden the definition of health care policy to policies targeting social inequality (Mechanic 2007). Residential segregation affects health outcomes in several different ways. First, income, education, and occupation are all strongly related to health (Adler and Newman 2002). Segregation is a key mechanism through which socioeconomic inequality is perpetuated and reinforced, as it hinders the upward mobility of disadvantaged groups by limiting their educational and employment opportunities. Second, segregation increases minority exposure to unhealthy neighborhood environments. Residential segregation creates areas with concentrated poverty and unemployment, both of which are key factors that predict violence and create racial differences in homicide (Samson and Wilson 1995). Neighborhood characteristics, such as exposure to environmental hazards, fear of violence, and access to grocery stores, affect health risks and health behaviors (Cheadle et al. 1991). Tobacco and alcohol industries also advertise their products disproportionately in poor, minority areas (Moore, Williams, and Qualls 1996). Finally, residential segregation leads to inequalitie in health care resources, which contributes to disparities in quality of treatment (Smedley, Stith, and Nelson 2002).

  9. Measuring Inequality and Segregation

    CERN Document Server

    Roberto, Elizabeth

    2015-01-01

    In this paper, I introduce the Divergence Index, a conceptually intuitive and methodologically rigorous measure of inequality and segregation. The index measures the difference between a distribution of interest and another empirical, theoretical, or normative distribution. The Divergence Index provides flexibility in specifying a theoretically meaningful basis for evaluating inequality. It evaluates how surprising an empirical distribution is given a theoretical distribution that represents equality. I demonstrate the unique features of the new measure, as well as deriving its mathematical equivalence with Theil's Inequality Index and the Information Theory Index. I compare the dynamics of the measures using simulated data, and an empirical analysis of racial residential segregation in the Detroit, MI, metro area. The Information Theory Index has become the gold standard for decomposition analyses of segregation. I show that although the Information Theory Index can be decomposed for subareas, it is misleadi...

  10. Synthesis of an organic-inorganic salt of (C2H5NO22H4SiW12O40 and investigation of its anti-viral effect on the Tobacco Mosaic Virus (TMV

    Directory of Open Access Journals (Sweden)

    Majid Saghi

    2015-05-01

    Full Text Available Polyoxometalates (POMs are important inorganic compounds that have been considered specifically in recent years due to abundant attributes and applications. Those POMs that have one central tetrahedral atom called keggin. The binding Amino-acid groups to keggin structure give the antivirus effect to these compounds. A new organic-inorganic hybrid structure, with formula (C2H5NO22H4SiW12O40 was synthesized (C2H5NO2 = Glycine = Gly. Investigation on Anti-viral effect of this compound showed the (Gly2H4SiW12O40 prevents infection of Tobacco Mosaic Virus (TMV on the Nicotiana tabacum plants.

  11. Factors affecting hydrogen-assisted cracking in a commercial tempered martensitic steel: Mn segregation, MnS, and the stress state around abnormal cracks

    International Nuclear Information System (INIS)

    The purpose of this paper is to reveal the dominant factors affecting tensile fracture under a hydrogen gas atmosphere. Tensile tests were conducted in hydrogen gas with circumferentially-notched specimens of a commercial tempered martensitic steel. Two specimens were exposed to hydrogen gas for 48 h before tensile testing; the other two specimens were not pre-charged. Longitudinal cracks along the loading direction and a transverse crack perpendicular to the loading direction were observed on a cross section of the non-charged specimen, but there was only one small crack on a cross section of the pre-charged specimen. Electron back scatter diffraction, energy dispersive X-ray spectrometry and finite element method analyses were applied to clarify the relationships among the longitudinal crack, Mn segregation, microstructures of martensitic steel and hydrogen. As a result, it has been demonstrated that Mn segregation and MnS promote hydrogen-assisted cracking in the tempered martensitic steel, causing the longitudinal cracking which is a mechanically non-preferential direction in homogeneous situations. More specifically, we have shown that the role of the Mn segregation is to promote the hydrogen-enhanced decohesion effect (HEDE), which is particularly important for crack propagation in the present case. These considerations indicate that the presence of Mn is crucially important for hydrogen-assisted cracking associated with hydrogen-enhanced localized plasticity (HELP) as well as HEDE

  12. Residential Segregation by Occupation and Race in Ten Urbanized Areas, 1950-1970.

    Science.gov (United States)

    Simkus, Albert A.

    1978-01-01

    This study is directed at measuring the changes in residential segregation in ten United States urbanized areas during the 1950s and 1960s. Changes in the relationship between racial and occupational residential segregation are also examined. (Author/EB)

  13. Racial Segregation and the American Foreclosure Crisis.

    Science.gov (United States)

    Rugh, Jacob S; Massey, Douglas S

    2010-10-01

    Although the rise in subprime lending and the ensuing wave of foreclosures was partly a result of market forces that have been well-identified in the literature, in the United States it was also a highly racialized process. We argue that residential segregation created a unique niche of poor minority clients who were differentially marketed risky subprime loans that were in great demand for use in mortgage-backed securities that could be sold on secondary markets. We test this argument by regressing foreclosure actions in the top 100 U.S. metropolitan areas on measures of black, Hispanic, and Asian segregation while controlling for a variety of housing market conditions, including average creditworthiness, the extent of coverage under the Community Reinvestment Act, the degree of zoning regulation, and the overall rate of subprime lending. We find that black residential dissimilarity and spatial isolation are powerful predictors of foreclosures across U.S. metropolitan areas. In order to isolate subprime lending as the causal mechanism whereby segregation influences foreclosures, we estimate a two-stage least squares model that confirms the causal effect of black segregation on the number and rate of foreclosures across metropolitan areas. In the United States segregation was an important contributing cause of the foreclosure crisis, along with overbuilding, risky lending practices, lax regulation, and the bursting of the housing price bubble. PMID:25308973

  14. The Role of Residential Segregation in Contemporary School Segregation

    Science.gov (United States)

    Frankenberg, Erica

    2013-01-01

    Inaction to address housing segregation in metropolitan areas has resulted in persistently high levels of residential segregation. As the Supreme Court has recently limited school districts' voluntary integration efforts, this article considers the role of residential segregation in maintaining racially isolated schools, namely what is known…

  15. Vertical gender segregation in the economic theories within the European Union

    OpenAIRE

    Patrycja Zwiech

    2013-01-01

    The objective of this paper is to describe and organise the determinants of vertical gender segregation in the workplace described in the economic theories as well as to evaluate vertical gender segregation in Member States. In order to achieve the said objective, three tasks were performed, namely: showing determinants of vertical gender segregation in the economic theories, analysing the index of vertical gender segregation in Member States and analysing the level of relational index of gen...

  16. Black Residential Segregation since the 1948 "Shelley v. Kraemer" Decision.

    Science.gov (United States)

    Darden, Joe T.

    1995-01-01

    Assesses the state of black residential segregation since the court case "Shelley v. Kraemer." Focus is placed on metropolitan areas generally and on St. Louis and Detroit, in particular. It is concluded that blacks have made little progress in reducing segregation in housing since the 1948 court case that outlawed restrictive covenants on the…

  17. Residential Segregation and School Integration.

    Science.gov (United States)

    Rivkin, Steven G.

    1994-01-01

    Asserts that school districts' efforts to integrate schools have failed to ameliorate the racial isolation of black students. Finds that schools remain segregated primarily because of continued residential segregation and that school integration efforts have had little long-term effect on residential segregation. (CFR)

  18. Significance of the state of segregation of the carbide phase on the toughness properties of 20 MnMoNi 5 5 forgings

    International Nuclear Information System (INIS)

    When measured in the heat treated wall thickness of heavy forgings, 20 Mn Mo Ni 5 5 steel is so low in allow that it is unavoidable that large parts of higher bainite will occur in the structure of the pieces. In order to obtain the best possible notch impact strength values, tempering is of particular importance. It must be done so that there is the least possible segregation of molybdenum carbide Mo2C in the bainite ferrite. This requires the use of not too high tempering temperatures together with an upper limit of tempering time. Similar considerations apply for stress relieving treatment. (orig.)

  19. Segregation in Minds

    OpenAIRE

    Rácz, Attila

    2015-01-01

    In this paper, I explore socio-spatial segregation from a particular perspective, which may probably be considered a novelty in the investigation of spatial social patterns, as it focuses on questions such as: What kind of distinction occurs between socio-spatial patterns designated by statistical data and the cognitive representations of those patterns in people's minds? and What explains these diff erences, and what kind of impact can they generate?

  20. Patterns of residential segregation

    OpenAIRE

    Louf, Rémi; Barthelemy, Marc

    2015-01-01

    The spatial distribution of income shapes the structure and organisation of cities and its understanding has broad societal implications. Despite an abundant literature, many issues remain however unclear: there is no clear definition of what segregation is, no unambiguous definition of income classes, no clear way to identify neighborhoods, and no method to deal with the polycentric organization of large cities. In this paper, we address all these questions within a unique theoretical framew...

  1. Aversive Racism and Intergroup Contact Theories: Cultural Competence in a Segregated World

    Science.gov (United States)

    Rodenborg, Nancy A.; Boisen, Laura A.

    2013-01-01

    The United States remains highly segregated, and social work students are likely to live and work in segregated contexts. What implications does this have for their cultural competence? Does segregation affect social workers' ability to serve diverse clients without bias? This article reviews two social psychology theories, aversive racism…

  2. 50 Years after "Brown": Segregation in the Miami-Dade County Public Schools

    Science.gov (United States)

    Moore, James

    2004-01-01

    Fifty years after the "Brown v. Board of Education" decision outlawed de jure segregation in American schools, many school districts remain segregated. Despite numerous efforts aimed at desegregation, residential segregation--the primary barrier to significant school desegregation--remains entrenched throughout the United States. The Miami-Dade…

  3. Alma and Karl Taeuber, Residential Segregation in U.S. Cities, 1965. CSISS Classics

    OpenAIRE

    Brown, Nina

    2002-01-01

    The Taeubers demonstrated the value of census mapping of residential and educational segregation in the United States. Their early attempt to integrate quantitative segregation research and cartographic techniques (Negroes in Cities, 1965), used the dissimilarity index to compare residential segregation in 207 U.S. cities.

  4. Evaluation of the impact of camelina oil-containing diets on the expression of genes involved in the innate anti-viral immune response in Atlantic cod (Gadus morhua).

    Science.gov (United States)

    Booman, Marije; Xu, Qingheng; Rise, Matthew L

    2014-11-01

    To improve sustainability of aquaculture, especially for carnivorous species like Atlantic cod, replacement of fish oil-based diets with vegetable oil-based diets has been studied. The use of vegetable oil in fish feeds can significantly change the fatty acid composition of fish tissues, and given the importance of fatty acids in inflammation and immunity, this change could potentially impact the immune response and health of the fish. The oilseed Camelina sativa is a promising source for this vegetable oil, because of the high oil content of its seeds (40%), a higher n-3 fatty acid content than most other oilseeds, and a high amount of γ-tocopherol. This study aims to investigate the effect of the replacement of dietary fish oil with oil from Camelina sativa on the immune response of Atlantic cod, as measured by the gene expression in spleen. Juvenile cod were fed on a fish oil-based diet (FO) or one of two diets in which camelina oil replaced 40% or 80% of fish oil (40CO and 80CO respectively) for 67 days, after which they were injected with either the viral mimic polyriboinosinic polyribocytidylic acid (pIC), or phosphate-buffered saline (PBS) as a control. Microarray analysis was used to determine the effect of the diet on the basal spleen transcriptome (pre-injection), and on the response to pIC (24 h post-injection). No marked differences in the spleen transcriptome were found between the three diets, either before or after injection with pIC. All fish, regardless of diet, showed a strong anti-viral response 24 h after pIC injection, with more than 500 genes having a significant difference of expression of 2-fold or higher compared to the PBS-injected fish for the FO, 40CO and 80CO diets. Gene Ontology annotation analysis of the three pIC-responsive gene lists indicated they were highly similar, and that the term 'immune system process' was significantly enriched in the pIC-responsive gene lists for all three diets. QPCR analysis for 5 genes with a known

  5. Inequality, residential segregation by income, and mortality in US cities

    OpenAIRE

    Lobmayer, P; Wilkinson, R.

    2002-01-01

    Study objective: This study was designed to discover whether the relation between income inequality and population death rates within the United States was mediated by the degree of residential segregation between rich and poor.

  6. Patterns of Residential Segregation.

    Science.gov (United States)

    Louf, Rémi; Barthelemy, Marc

    2016-01-01

    The spatial distribution of income shapes the structure and organisation of cities and its understanding has broad societal implications. Despite an abundant literature, many issues remain unclear. In particular, all definitions of segregation are implicitely tied to a single indicator, usually rely on an ambiguous definition of income classes, without any consensus on how to define neighbourhoods and to deal with the polycentric organization of large cities. In this paper, we address all these questions within a unique conceptual framework. We avoid the challenge of providing a direct definition of segregation and instead start from a definition of what segregation is not. This naturally leads to the measure of representation that is able to identify locations where categories are over- or underrepresented. From there, we provide a new measure of exposure that discriminates between situations where categories co-locate or repel one another. We then use this feature to provide an unambiguous, parameter-free method to find meaningful breaks in the income distribution, thus defining classes. Applied to the 2014 American Community Survey, we find 3 emerging classes-low, middle and higher income-out of the original 16 income categories. The higher-income households are proportionally more present in larger cities, while lower-income households are not, invalidating the idea of an increased social polarisation. Finally, using the density-and not the distance to a center which is meaningless in polycentric cities-we find that the richer class is overrepresented in high density zones, especially for larger cities. This suggests that density is a relevant factor for understanding the income structure of cities and might explain some of the differences observed between US and European cities. PMID:27315283

  7. Patterns of Residential Segregation.

    Directory of Open Access Journals (Sweden)

    Rémi Louf

    Full Text Available The spatial distribution of income shapes the structure and organisation of cities and its understanding has broad societal implications. Despite an abundant literature, many issues remain unclear. In particular, all definitions of segregation are implicitely tied to a single indicator, usually rely on an ambiguous definition of income classes, without any consensus on how to define neighbourhoods and to deal with the polycentric organization of large cities. In this paper, we address all these questions within a unique conceptual framework. We avoid the challenge of providing a direct definition of segregation and instead start from a definition of what segregation is not. This naturally leads to the measure of representation that is able to identify locations where categories are over- or underrepresented. From there, we provide a new measure of exposure that discriminates between situations where categories co-locate or repel one another. We then use this feature to provide an unambiguous, parameter-free method to find meaningful breaks in the income distribution, thus defining classes. Applied to the 2014 American Community Survey, we find 3 emerging classes-low, middle and higher income-out of the original 16 income categories. The higher-income households are proportionally more present in larger cities, while lower-income households are not, invalidating the idea of an increased social polarisation. Finally, using the density-and not the distance to a center which is meaningless in polycentric cities-we find that the richer class is overrepresented in high density zones, especially for larger cities. This suggests that density is a relevant factor for understanding the income structure of cities and might explain some of the differences observed between US and European cities.

  8. Equipment Used Prior to Turnover to Operations: Lessons Learned on Communication and Material Segregation, Savannah River Nuclear Solutions, United States of America

    International Nuclear Information System (INIS)

    In late 2013, the procurement of 200 new L-Area bundles was initiated as part of a project to install new storage racks in the L-Area basin. The L-Area bundles are safety significant (SS) aluminum tubes used to contain spent fuel assemblies within the storage racks. Following initiation of rack and bundle procurement, the rack installation project was cancelled with the agreement to fund receipt of the racks and bundles but stop short of rack installation. During fabrication of the bundles by an offsite vendor, a supplier deviation disposition request (SDDR) was initiated to allow an additional alloy of aluminum and a different fabrication method to be used for fabrication of the bundle lids. Incorporation of the associated design changes into site drawings was to be performed at a later date due to competing priorities. Fabrication of the L-Area bundles was completed and the bundles were delivered to the L-Area in January 2013. Because the SDDR driven design change had not been incorporated into the site drawing, a decision was made to segregate the bundles to prevent inadvertent use. Operators receiving the bundles were told to barricade the bundles, but the reason for the barricade was not adequately communicated. As a result, the bundles were stored near previously accepted bundles with a barricade that specified only property, plant and equipment (PPE) required to enter. The reason for the segregation was later verbally communicated during weekly safety focus meetings. In May 2013, during preparations for unloading of an offsite spent fuel shipment, operators were sent to obtain two L-Area bundles. Bundles were selected from the accepted batch. However, owing to issues regarding the fit, lids were selected from the batch of new bundles within the barricade. The bundles were then loaded with spent fuel and stored in the L-Basin racks. Days later, during a facility walk-down, an L-Area shift operations manager (SOM) noticed that two of the new bundle lids were

  9. Waste segregation procedures and benefits

    International Nuclear Information System (INIS)

    Segregation is a critical first step in handling hazardous and radioactive materials to minimize the generation of regulated wastes. In addition, segregation can significantly reduce the complexity and the total cost of managing waste. Procedures at Sandia National Laboratories, Albuquerque require that wastes be segregated, first, by waste type (acids, solvents, low level radioactive, mixed, classified, etc.). Higher level segregation requirements, currently under development, are aimed at enhancing the possibilities for recovery, recycle and reapplication; reducing waste volumes; reducing waste disposal costs, and facilitating packaging storage, shipping and disposal. 2 tabs

  10. Source Segregation and Collection of Source-Segregated Waste

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund; Matsufuji, Y.

    2011-01-01

    The Segregation of individual material fractions at the waste source and keeping the fractions separate for collection is one of the key issues in modern waste management. In most cases the waste is just kept segregated from other waste according to certain criteria that improve the possibility of...... optimal handling of the waste. But in a few cases, the waste must also be separated at source, for example removing the protective plastic cover from a commercial advertisement received by mail, prior to putting the advertisement into the waste collection bin for recyclable paper. These issues are often...... more important it is to consider source segregation of the waste, since the amount of waste links to the possibility of obtaining manageable amounts of segregated waste with reasonable logistics as well as to the manpower that can be allocated at the source to perform source segregation of waste...

  11. Multilevel Modeling of Social Segregation

    Science.gov (United States)

    Leckie, George; Pillinger, Rebecca; Jones, Kelvyn; Goldstein, Harvey

    2012-01-01

    The traditional approach to measuring segregation is based upon descriptive, non-model-based indices. A recently proposed alternative is multilevel modeling. The authors further develop the argument for a multilevel modeling approach by first describing and expanding upon its notable advantages, which include an ability to model segregation at a…

  12. The Dimensions of Residential Segregation.

    Science.gov (United States)

    Massey, Douglas S.; Denton, Nancy A.

    1988-01-01

    Evaluates 20 potential indicators of residential segregation using census data on Hispanics, Blacks, Asians, and non-Hispanic Whites in 60 U.S. metropolitan areas. Factor-analyzes the results to select a single best indicator for each of five dimensions of residential segregation. Contains 69 references and 22 statistical formulas. (SV)

  13. SOLID WASTE SEGREGATION BEHAVIOR AMONG URBAN WOMEN

    OpenAIRE

    P. Mohamed Nisha; Raji Sugumar

    2014-01-01

    This study examined the solid waste segregation behavior of the women of Chennai city of Tamil Nadu state. Using a structured, self-developed interview schedule, 120 women were selected randomly for the survey with equal representation from the three regions of Chennai city. Findings revealed that most of the waste that is being generated in the households of the selected samples was organic, recyclable and reusable. The sample women are not highly knowledgeable about the solid...

  14. Patterns of residential segregation

    CERN Document Server

    Louf, Rémi

    2015-01-01

    The spatial distribution of income shapes the structure and organisation of cities and its understanding has broad societal implications. Despite an abundant literature, many issues remain however unclear: there is no clear definition of what segregation is, no unambiguous definition of income classes, no clear way to identify neighborhoods, and no method to deal with the polycentric organization of large cities. In this paper, we address all these questions within a unique theoretical framework. We assume that households belonging to the same class tend to live close to each other, and households from different classes tend to avoid one another. Applied to the US 2000 Census Income data, 3 distinct classes emerge from the clustering of the original 16 income classes. Using these unambiguously defined classes, we cluster together contiguous similar areas and find that the number of clusters for each category scales with the city population, an effect that is more pronounced for rich households. Finally, using...

  15. Human alloantigen-specific anergic cells induced by a combination of CTLA4-Ig and CsA maintain anti-leukemia and anti-viral cytotoxic responses.

    Science.gov (United States)

    Comoli, P; Locatelli, F; Moretta, A; Montagna, D; Calcaterra, V; Cometa, A; Basso, S; Zecca, M; Maccario, R

    2001-06-01

    The success of allogeneic hematopoietic stem cell transplantation from HLA-disparate donors depends on the development of new strategies for graft-versus-host disease prevention able to target specifically donor antihost alloreactivity, while preserving GVL and antiviral immune surveillance. Recent experimental and clinical work has shown the feasibility of an approach based on induction of anergy to host alloantigens through blockade of B7/CD28 costimulatory signal in donor T cells, but data on the impact of this strategy on the recovery of the immune system are still lacking. We devised an ex vivo method for induction of host alloantigen-specific unresponsiveness based on treatment with the B7/CD28 blocking agent CTLA4-Ig associated with CsA. We then proceeded to assess the maintenance of an effective immune response towards viral pathogens and tumor cells after CTLA4-Ig/CsA treatment, by measuring the frequency of CTL precursors directed against CMV- and EBV-infected targets, and against autologous leukemic blasts. We demonstrated that (1) CTLA4-Ig and CsA can act synergistically in inducing a state of unresponsiveness to alloantigens; (2) the number of leukemia-reactive, EBV-specific and CMV-specific CTLp is not impaired by CTLA4-Ig/CsA treatment. Our data provide the first direct in vitro evidence that it is possible to preserve antiviral and antileukemia effector cells after blockade of CD28/B7 interaction during MLR. PMID:11548844

  16. Sex segregation in undergraduate engineering majors

    Science.gov (United States)

    Litzler, Elizabeth

    reducible to individual choice. This dissertation provides a broad, descriptive view of the state of sex segregation in engineering as well as a careful analysis of how individual and institutional factors inhibit or encourage sex segregation. This study contributes to the research literature through the use of novel data, testing of occupational segregation theories, and the use of multiple levels of analysis. The analyses provide new insight into an enduring phenomenon, and suggest new avenues for understanding sex segregation in higher education.

  17. HTLV-1 bZIP Factor Impairs Anti-viral Immunity by Inducing Co-inhibitory Molecule, T Cell Immunoglobulin and ITIM Domain (TIGIT.

    Directory of Open Access Journals (Sweden)

    Keiko Yasuma

    2016-01-01

    Full Text Available Human T-cell leukemia virus type 1 (HTLV-1 infects CD4+ T cells and induces proliferation of infected cells in vivo, which leads to the onset of adult T-cell leukemia (ATL in some infected individuals. The HTLV-1 bZIP factor (HBZ gene, which is encoded in the minus strand of HTLV-1, plays critical roles in pathogenesis. In this study, RNA-seq and ChIP-seq analyses using HBZ transduced T cells revealed that HBZ upregulates the expression and promoter acetylation levels of a co-inhibitory molecule, T cell immunoglobulin and ITIM domain (TIGIT, in addition to those of regulatory T cells related genes, Foxp3 and Ccr4. TIGIT was expressed on CD4+ T cells from HBZ-transgenic (HBZ-Tg mice, and on ATL cells and HTLV-1 infected CD4+ T cells of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP in vivo. Expression of Blimp1 and IL-10 was upregulated in TIGIT+CD4+ cells of HBZ-Tg mice compared with TIGIT-CD4+ T cells, suggesting the correlation between TIGIT expression and IL-10 production. When CD4+ T cells from HBZ-Tg mice were stimulated with TIGIT's ligand, CD155, their production of the inhibitory cytokine IL-10 was enhanced. Furthermore, dendritic cells from HBZ-Tg mice produced high levels of IL-10 after stimulation. These data suggest that HBZ alters immune system to suppressive state via TIGIT and IL-10. Importantly, TIGIT suppressed T-cell responses to another HTLV-1 virus protein, Tax, in vitro. Blocking of TIGIT and PD-1 slightly increased anti-Tax T-cell activity in some HAM/TSP patients. These results suggest that HBZ-induced TIGIT on HTLV-1 infected cells impairs T-cell responses to viral antigens. This study shows that HBZ-induced TIGIT plays a pivotal role in attenuating host immune responses and shaping a microenvironment favorable to HTLV-1.

  18. Traveling Granular Segregation Patterns in a Long Drum Mixer

    OpenAIRE

    Choo, Kiam; Molteno, T. C. A.; Morris, Stephen W.

    1997-01-01

    Mixtures of granular media often exhibit size segregation along the axis of a partially-filled, horizontal, rotating cylinder. Previous experiments have observed axial bands of segregation that grow from concentration fluctuations and merge in a manner analogous to spinodal decomposition. We have observed that a new dynamical state precedes this effect in certain mixtures: bi-directional traveling waves. By preparing initial conditions, we found that the wave speed decreased with wavelength. ...

  19. Chromosome segregation in plant meiosis

    Directory of Open Access Journals (Sweden)

    Linda eZamariola

    2014-06-01

    Full Text Available Faithful chromosome segregation in meiosis is essential for ploidy stability over sexual life cycles. In plants, defective chromosome segregation caused by gene mutations or other factors leads to the formation of unbalanced or unreduced gametes creating aneuploid or polyploid progeny, respectively. Accurate segregation requires the coordinated execution of conserved processes occurring throughout the two meiotic cell divisions. Synapsis and recombination ensure the establishment of chiasmata that hold homologous chromosomes together allowing their correct segregation in the first meiotic division, which is also tightly regulated by cell-cycle dependent release of cohesin and monopolar attachment of sister kinetochores to microtubules. In meiosis II, bi-orientation of sister kinetochores and proper spindle orientation correctly segregate chromosomes in four haploid cells. Checkpoint mechanisms acting at kinetochores control the accuracy of kinetochore-microtubule attachment, thus ensuring the completion of segregation. Here we review the current knowledge on the processes taking place during chromosome segregation in plant meiosis, focusing on the characterization of the molecular factors involved.

  20. Anti-Viral Drugs for Human Adenoviruses

    Directory of Open Access Journals (Sweden)

    Chor Wing Sing

    2010-10-01

    Full Text Available There are many stages in the development of a new drug for viral infection and such processes are even further complicated for adenovirus by the fact that there are at least 51 serotypes, forming six distinct groups (A–F, with different degree of infectivity. This review attempts to address the importance of developing pharmaceuticals for adenovirus and also review recent development in drug discovery for adenovirus, including newer strategies such as microRNA approaches. Different drug screening strategies will also be discussed.

  1. Dynamics of Transformation from Segregation to Mixed Wealth Cities

    CERN Document Server

    Sahasranaman, Anand

    2016-01-01

    We model the dynamics of the Schelling model for agents described simply by a continuously distributed variable - wealth. Agents move to neighborhoods where their wealth is not lesser than that of some proportion of their neighbors, the threshold level. As in the case of the classic Schelling model where segregation obtains between two races, we find here that wealth-based segregation occurs and persists. However, introducing uncertainty into the decision to move - that is, with some probability, if agents are allowed to move even though the threshold level condition is contravened - we find that even for small proportions of such disallowed moves, the dynamics no longer yield segregation but instead sharply transition into a persistent mixed wealth distribution. We investigate the nature of this sharp transformation between segregated and mixed states, and find that it is because of a non-linear relationship between allowed moves and disallowed moves. For small increases in disallowed moves, there is a rapid...

  2. Can topology reshape segregation patterns?

    CERN Document Server

    Gandica, Yerali; Carletti, Timoteo

    2015-01-01

    We consider a metapopulation version of the Schelling model of segregation over several complex networks and lattice. We show that the segregation process is topology independent and hence it is intrinsic to the individual tolerance. The role of the topology is to fix the places where the segregation patterns emerge. In addition we address the question of the time evolution of the segregation clusters, resulting from different dynamical regimes of a coarsening process, as a function of the tolerance parameter. We show that the underlying topology may alter the early stage of the coarsening process, once large values of the tolerance are used, while for lower ones a different mechanism is at work and it results to be topology independent.

  3. School Desegregation and Residential Segregation.

    Science.gov (United States)

    Billingsley, Andrew; And Others

    1979-01-01

    This statement on school and residential segregation, signed by 38 educators and social scientists, was prepared for attorneys connected with litigation concerning the Dayton and Columbus school systems. (RLV)

  4. Applied thermodynamics: Grain boundary segregation

    Czech Academy of Sciences Publication Activity Database

    Lejček, Pavel; Zheng, L.; Hofmann, S.; Šob, Mojmír

    2014-01-01

    Roč. 16, č. 3 (2014), s. 1462-1484. ISSN 1099-4300 R&D Projects: GA ČR(CZ) GAP108/12/0311; GA ČR GAP108/12/0144; GA MŠk(CZ) ED1.1.00/02.0068 Institutional support: RVO:68378271 ; RVO:68081723 Keywords : interfacial segregation * Gibbs energy of segregation * enthalpy * entropy * volume * grain boundaries * iron Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.502, year: 2014

  5. Residential Segregation in General Equilibrium

    OpenAIRE

    Bayer, Patrick; McMillan, Robert; Rueben, Kim

    2005-01-01

    This paper studies the causes and consequences of racial segregation using a new general equilibrium model that treats neighborhood compositions as endogenous. The model is estimated using unusually detailed restricted Census microdata covering the entire San Francisco Bay Area, and in combination with a rich array of econometric estimates, serves as a powerful tool for carrying out counterfactual simulations that shed light on the causes and consequences of segregation. In terms of causes, a...

  6. Heterogeneous Immigration, Segregation and Trade

    OpenAIRE

    Fabien Candau

    2011-01-01

    By introducing taste heterogeneity between mobile workers in a New Economic Geography (NEG) model where the housing price is the main driving force behind dispersion of workers we show that residential segregation and agglomeration are not the sole stable equilibria and that dispersion also emerges with trade liberalization. In addition we find that contrary to the Tiebout hypothesis where segregation is efficient, here it is the dispersed and mixed equilibrium which can be improving for all.

  7. School Segregation: The Case of Amsterdam.

    Science.gov (United States)

    Gramberg, Peter

    1998-01-01

    Deals with facets of school segregation in Amsterdam, a city in which two-thirds of youth have a non-native background. The role of residential segregation in the segregation of elementary schools and the importance of educational background in the segregation of secondary schools are discussed. There are implications for schooling in the United…

  8. A Revaluation of Indexes of Residential Segregation

    Science.gov (United States)

    Winship, Christopher

    1977-01-01

    Shows that there are at least two different perspectives from which residential segregation can be examined. Segregation can be measured as it deviates from a situation of complete desegregation or in terms of a situation in which there is random segregation in the city. New criteria for indexes of residential segregation are developed. (Author/JM)

  9. Matching Residential Mobility to Raced-Based Neighborhood Preferences in Los Angeles: Implications for Racial Residential Segregation

    OpenAIRE

    Jarvis, Benjamin Fletcher

    2015-01-01

    Neighborhood racial composition preferences have the potential to produce extreme residential segregation between racial groups. Whites' preferences to avoid Blacks, and Blacks' preferences to maintain residential contact with their own group can induce high levels of White-Black segregation. Similar preferences can lead to segregation for Asians and Latinos. These theoretical facts have lead some observers to attribute continued residential segregation in the United States to preferences. Th...

  10. Minimization and segregation of radioactive wastes

    International Nuclear Information System (INIS)

    The report will serve as one of a series of technical manuals providing reference material and direct know-how to staff in radioisotope user establishments and research centres in Member States without nuclear power and the associated range of complex waste management operations. Considerations are limited to the minimization and segregation of wastes, these being initial steps on which the efficiency of the whole waste management system depends. The minimization and segregation operations are examined in the context of the restricted quantities and predominantly shorter lived activities of wastes from nuclear research, production and usage of radioisotopes. Liquid and solid wastes only are considered in the report. Gaseous waste minimization and treatment are specialized subjects and are not examined in this document. Gaseous effluent treatment in facilities handling low and intermediate level radioactive materials has been already the subject of a detailed IAEA report. Management of spent sealed sources has specifically been covered in a previous manual. Conditioned sealed sources must be taken into account in segregation arrangements for interim storage and disposal where there are exceptional long lived highly radiotoxic isotopes, particularly radium or americium. These are unlikely ever to be suitable for shallow land burial along with the remaining wastes. 30 refs, 5 figs, 8 tabs

  11. Settle for Segregation or Strive for Diversity? A Defining Moment for Maryland's Public Schools

    Science.gov (United States)

    Ayscue, Jennifer B.

    2013-01-01

    Maryland, as one of 17 states that had de jure segregation, has an intense history of school segregation. Following the 1954 Brown decision, school districts across the state employed various methods to desegregate their schools, including mandatory busing in Prince George's County, magnet schools in Montgomery County, and a freedom of choice plan…

  12. Public School Segregation in Metropolitan Areas

    OpenAIRE

    Charles T. Clotfelter

    1998-01-01

    This paper presents measures of segregation in public schools for metropolitan areas. It shows that, not only are metropolitan areas very segregated, most of that segregation is due to racial disparities between districts rather than segregative patterns within districts. Metropolitan areas in the South and West tend to have larger districts, and thus feature less fragmentation by school district. Segregation at the metropolitan level appears to vary systematically with size, racial mix, and ...

  13. Occupational segregation of immigrant women in Spain

    OpenAIRE

    Coral del Río; Olga Alonso-Villar

    2010-01-01

    The aim of this paper is to analyze occupational segregation in the Spanish labor market from a gender and an immigration perspective. In doing so, several local and overall segregation measures are used. Our results suggest that immigrant women in Spain suffer a double segregation since segregation affects them to a greater extent than it does either native women or immigrant men. There are, however, remarkable discrepancies among the segregation of immigrant women depending on their region ...

  14. Racial segregation and maternal smoking during pregnancy: a multilevel analysis using the racial segregation interaction index

    OpenAIRE

    Yang, Tse-Chuan; Shoff, Carla; Aggie J. Noah; Black, Nyesha; Sparks, Corey S.

    2014-01-01

    Drawing from both the place stratification and ethnic enclave perspectives, we use multilevel modeling to investigate the relationships between women’s race/ethnicity (i.e., non-Hispanic white, non-Hispanic black, Asian, and Hispanic) and maternal smoking during pregnancy; and examine if these relationships are moderated by racial segregation in the continental United States. The results show that increased interaction with whites is associated with increased probability of maternal smoking d...

  15. Racial Segregation and the American Foreclosure Crisis

    OpenAIRE

    Rugh, Jacob S.; Massey, Douglas S.

    2010-01-01

    Although the rise in subprime lending and the ensuing wave of foreclosures was partly a result of market forces that have been well-identified in the literature, in the United States it was also a highly racialized process. We argue that residential segregation created a unique niche of poor minority clients who were differentially marketed risky subprime loans that were in great demand for use in mortgage-backed securities that could be sold on secondary markets. We test this argument by reg...

  16. Grain Boundary Segregation in Metals

    CERN Document Server

    Lejcek, Pavel

    2010-01-01

    Grain boundaries are important structural components of polycrystalline materials used in the vast majority of technical applications. Because grain boundaries form a continuous network throughout such materials, their properties may limit their practical use. One of the serious phenomena which evoke these limitations is the grain boundary segregation of impurities. It results in the loss of grain boundary cohesion and consequently, in brittle fracture of the materials. The current book deals with fundamentals of grain boundary segregation in metallic materials and its relationship to the grain boundary structure, classification and other materials properties.

  17. Restoration of segregated, physiological neuronal connectivity by desynchronizing stimulation.

    Science.gov (United States)

    Hauptmann, Christian; Tass, Peter A

    2010-10-01

    The loss of segregation of neuronal signal processing pathways is an important hypothesis for explaining the origin of functional deficits as associated with Parkinson's disease. Here we use a modeling approach which is utilized to study the influence of deep brain stimulation on the restoration of segregated activity in the target structures. Besides the spontaneous activity of the target network, the model considers a weak sensory input mimicking signal processing tasks, electrical deep brain stimulation delivered through a standard DBS electrode and synaptic plasticity. We demonstrate that the sensory input is capable of inducing a modification of the network structure which results in segregated microcircuits if the network is initialized in the healthy, desynchronized state. Depending on the strength and coverage, the sensory input is capable of restoring the functional sub-circuits even if the network is initialized in the synchronized, pathological state. Weak coordinated reset stimulation, applied to a network featuring a loss of segregation caused by global synchronization, is able to restore the segregated activity and to truncate the pathological, synchronized activity. PMID:20811089

  18. Linking Dichotomous Segregation with Multi-group Segregation: Weighted Segregation Ratios in Selected U. S. Metropolitan Areas

    OpenAIRE

    Hao, Lingxin; Fong, Eric

    2011-01-01

    The U. S. residential landscape is increasingly multi-racial and multi-ethnic, giving rise to the question of how to compare dichotomous segregation among multiple groups living in the same area. To address the problem in the existing dichotomous approach, which offers no common basis for comparing dichotomous segregation among multiple groups, this paper develops a weighted segregation ratio approach based on Theil's segregation index and its additive decomposability. This approach can be us...

  19. Sexual orientation, prejudice and segregation

    NARCIS (Netherlands)

    E. Plug; D. Webbink; N. Martin

    2014-01-01

    This article examines whether gay and lesbian workers sort into tolerant occupations. With information on sexual orientation, prejudice, and occupational choice taken from Australian Twin Registers, we find that gays and lesbians shy away from prejudiced occupations. We show that our segregation res

  20. Nonequilibrium Segregation in Petroleum Reservoirs

    DEFF Research Database (Denmark)

    Shapiro, Alexander; Stenby, Erling Halfdan

    1999-01-01

    We analyse adsorption of a multicomponent mixture at high pressure on the basis of the potential theory of adsorption. The adsorbate is considered as a segregated mixture in the external field produced by a solid adsorbent. we derive an analytical equation for the thickness of a multicomponent fi...

  1. Linking integration and residential segregation

    NARCIS (Netherlands)

    Bolt, G.S.; Özüekren, A.S.; Phillips, Deborah

    2010-01-01

    In the introduction to this special issue of JEMS, we question the strong link which is often made between the integration of minority ethnic groups and their residential segregation. In the literature on neighbourhood effects, the residential concentration of minorities is seen as a major obstacle

  2. A Closer Look at Charter Schools and Segregation: Flawed Comparisons Lead to Overstated Conclusions

    Science.gov (United States)

    Ritter, Gary; Jensen, Nathan; Kisida, Brian; McGee, Joshua

    2010-01-01

    In January 2010, the UCLA-based Civil Rights Project (CRP) released "Choice without Equity: Charter School Segregation and the Need for Civil Rights Standards." The study intended to report on, among other things, levels of racial segregation in charter schools across the United States. The authors use 2007-08 data from the U.S. Department of…

  3. Forgotten History: Mexican American School Segregation in Arizona from 1900-1951

    Science.gov (United States)

    Powers, Jeanne M.

    2008-01-01

    This article documents the efforts by Mexican Americans to challenge school segregation in Arizona in the first half of the twentieth century. As in Texas and California, although state law never formally mandated the segregation of Mexican American students, school districts in Arizona often established separate "Mexican Schools" for Mexican…

  4. The Role of Governmental Policies in Promoting Residential Segregation in the St. Louis Metropolitan Area.

    Science.gov (United States)

    Judd, Dennis R.

    1997-01-01

    Explains how local, state, and federal governments have exacerbated or failed to take steps to reduce residential segregation in the St. Louis (Missouri) metropolitan area since the 1981 Liddell v. Board of Education decision that decided that school board and governmental housing policies had contributed to segregation in the city's schools. (SLD)

  5. Living Together Apart: Residential Segregation in Mixed Arab-Jewish Cities in Israel.

    Science.gov (United States)

    Falah, Ghazi

    1996-01-01

    Examines features of residential segregation in five mixed Arab-Jewish cities in Israel and the role of ideology and state politics among the charter group (Jewish) as a dominant factor in this social process. Findings reveal all five cities exhibit high indices of segregation and hypersegregation--a situation of neighbors without neighborly…

  6. Ethnic Segregation in Cities: New Forms and Explanations in a Dynamic World.

    Science.gov (United States)

    van Kempen, Ronald; Ozuekren, A. Sule

    1998-01-01

    Offers an overview of the explanatory factors of ethnic segregation and spatial concentration in modern welfare states. Traditional theories, behavioral theories, and theories in which restraints are central are reviewed, and restructuring processes are explored in light of economic change. The future of ethnic segregation is outlined. (SLD)

  7. Spatial Stream Segregation by Cats.

    Science.gov (United States)

    Javier, Lauren K; McGuire, Elizabeth A; Middlebrooks, John C

    2016-06-01

    Listeners can perceive interleaved sequences of sounds from two or more sources as segregated streams. In humans, physical separation of sound sources is a major factor enabling such stream segregation. Here, we examine spatial stream segregation with a psychophysical measure in domestic cats. Cats depressed a pedal to initiate a target sequence of brief sound bursts in a particular rhythm and then released the pedal when the rhythm changed. The target bursts were interleaved with a competing sequence of bursts that could differ in source location but otherwise were identical to the target bursts. This task was possible only when the sources were heard as segregated streams. When the sound bursts had broad spectra, cats could detect the rhythm change when target and competing sources were separated by as little as 9.4°. Essentially equal levels of performance were observed when frequencies were restricted to a high, 4-to-25-kHz, band in which the principal spatial cues presumably were related to sound levels. When the stimulus band was restricted from 0.4 to 1.6 kHz, leaving interaural time differences as the principal spatial cue, performance was severely degraded. The frequency sensitivity of cats in this task contrasts with that of humans, who show better spatial stream segregation with low- than with high-frequency sounds. Possible explanations for the species difference includes the smaller interaural delays available to cats due to smaller sizes of their heads and the potentially greater sound-level cues available due to the cat's frontally directed pinnae and higher audible frequency range. PMID:26993807

  8. The Geographic Scale of Metropolitan Racial Segregation

    OpenAIRE

    Reardon, Sean F.; Matthews, Stephen A.; O’Sullivan, David; Lee, Barrett A.; Firebaugh, Glenn; Farrell, Chad R.; BISCHOFF, KENDRA

    2008-01-01

    This article addresses an aspect of racial residential segregation that has been largely ignored in prior work: the issue of geographic scale. In some metropolitan areas, racial groups are segregated over large regions, with predominately white regions, predominately black regions, and so on, whereas in other areas, the separation of racial groups occurs over much shorter distances. Here we develop an approach—featuring the segregation profile and the corresponding macro/micro segregation rat...

  9. Measuring segregation: an activity space approach

    OpenAIRE

    Wong, David W. S.; Shaw, Shih-Lung

    2011-01-01

    While the literature clearly acknowledges that individuals may experience different levels of segregation across their various socio-geographical spaces, most measures of segregation are intended to be used in the residential space. Using spatially aggregated data to evaluate segregation in the residential space has been the norm and thus individual’s segregation experiences in other socio-geographical spaces are often de-emphasized or ignored. This paper attempts to provide a more comprehens...

  10. Is Segregation Bad for Your Health?

    OpenAIRE

    Kramer, Michael R; Hogue, Carol R.

    2009-01-01

    For decades, racial residential segregation has been observed to vary with health outcomes for African Americans, although only recently has interest increased in the public health literature. Utilizing a systematic review of the health and social science literature, the authors consider the segregation-health association through the lens of 4 questions of interest to epidemiologists: How is segregation best measured? Is the segregation-health association socially or biologically plausible? W...

  11. 18 CFR 401.113 - Segregable materials.

    Science.gov (United States)

    2010-04-01

    ... 18 Conservation of Power and Water Resources 2 2010-04-01 2010-04-01 false Segregable materials. 401.113 Section 401.113 Conservation of Power and Water Resources DELAWARE RIVER BASIN COMMISSION... Segregable materials. Any reasonably segregable portion of a record shall be provided to any...

  12. 17 CFR 31.12 - Segregation.

    Science.gov (United States)

    2010-04-01

    ... 17 Commodity and Securities Exchanges 1 2010-04-01 2010-04-01 false Segregation. 31.12 Section 31....12 Segregation. (a) Any person that accepts leverage customer funds from a leverage customer to enter.... Notwithstanding the foregoing, a leverage transaction merchant may exclude from its segregation...

  13. Gender-Segregated Schooling: A Problem Disguised as a Solution

    Science.gov (United States)

    Fabes, Richard A.; Martin, Carol Lynn; Hanish, Laura D.; Galligan, Kathrine; Pahlke, Erin

    2015-01-01

    Gender-segregated (GS) schooling has become popular in the United States despite the fact that every major review has concluded that GS schooling is not superior to coeducational schooling. Moreover, concern has been raised that GS schooling leads to negative effects, including increased gender stereotyping. We argue that these negative effects…

  14. Surface segregation energies in transition-metal alloys

    DEFF Research Database (Denmark)

    Ruban, Andrei; Skriver, Hans Lomholt; Nørskov, Jens Kehlet

    1999-01-01

    to the electrostatic potential and energy. We use the database to establish the major factors which govern surface segregation in transition metal alloys. We find that the calculated trends are well described by Friedel's rectangular state density model and that the few but significant deviations...

  15. Statistical Description of Segregation in a Powder Mixture

    DEFF Research Database (Denmark)

    Chapiro, Alexander; Stenby, Erling Halfdan

    1996-01-01

    In this paper we apply the statistical mechanics of powders to describe a segregated state in a mixture of grains of different sizes. Variation of the density of a packing with depth arising due to changes of particle configurations is studied. The statistical mechanics of powders is generalized...

  16. Characteristics of Sn segregation in Ge/GeSn heterostructures

    International Nuclear Information System (INIS)

    We report an investigation of Sn segregation in Ge/GeSn heterostructures occurred during the growth by molecular beam epitaxy. The measured Sn profile in the Ge layer shows that: (a) the Sn concentration decreases rapidly near the Ge/GeSn interface, and (b) when moving away from the interface, the Sn concentration reduced with a much slower rate. The 1/e decay lengths of the present system are much longer than those of the conventional group IV system of Ge segregation in the Si overlayer because of the smaller kinetic potential as modeled by a self-limited two-state exchange scheme. The demonstration of the Sn segregation shows the material characteristics of the heterostructure, which are needed for the investigation of its optical properties.

  17. Segregation in social networks based on acquaintanceship and trust.

    Science.gov (United States)

    DiPrete, Thomas A; Gelman, Andrew; McCormick, Tyler; Teitler, Julien; Zheng, Tian

    2011-01-01

    Using 2006 General Social Survey data, the authors compare levels of segregation by race and along other dimensions of potential social cleavage in the contemporary United States. Americans are not as isolated as the most extreme recent estimates suggest. However, hopes that "bridging" social capital is more common in broader acquaintanceship networks than in core networks are not supported. Instead, the entire acquaintanceship network is perceived by Americans to be about as segregated as the much smaller network of close ties. People do not always know the religiosity, political ideology, family behaviors, or socioeconomic status of their acquaintances, but perceived social divisions on these dimensions are high, sometimes rivaling racial segregation in acquaintanceship networks. The major challenge to social integration today comes from the tendency of many Americans to isolate themselves from others who differ on race, political ideology, level of religiosity, and other salient aspects of social identity. PMID:21648251

  18. Thermodynamic effect of elastic stress on grain boundary segregation of phosphorus in a low alloy steel

    International Nuclear Information System (INIS)

    Grain boundary (GB) segregation of P in 2.25Cr1Mo steel induced by elastic stress shows that the P equilibrium concentration, after reaching the non-equilibrium concentration maximum at critical time, returns to its initial thermal equilibrium level. This finding confirms the interesting phenomenon that the effect of elastic stress on GB segregation of P is significant in kinetics while slight in thermodynamics. Through extending the “pressure” in classical theory of chemical potential to the “elastic stress”, the thermodynamic effect of elastic stress on GB segregation is studied, and the relationship between elastic stress and segregation Gibbs energy is formulated. The formulas reveal that the difference in the segregation Gibbs energy between the elastically-stressed and non-stressed states depends on the excess molar volume of GB segregation and the magnitude of elastic stress. Model calculations in segregation Gibbs energy confirm that the effect of elastic stress on the thermodynamics of equilibrium GB segregation is slight, and the theoretical analyses considerably agree with the experimental results. The confirmation indicates that the nature of the thermodynamic effect is well captured. - Highlights: • GB segregation of P after stress aging returns to its initial thermal equilibrium level. • Relationship between elastic stress and segregation energy is formulated. • Thermodynamic effect relies on excess molar volume and magnitude of elastic stress. • Effect of elastic stress on Gibbs energy of GB segregation is estimated to be slight. • Complete theory of the effect of elastic stress on grain boundary segregation is setup

  19. Thermodynamic effect of elastic stress on grain boundary segregation of phosphorus in a low alloy steel

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Lei, E-mail: zhenglei_ustb@sina.com [School of Materials Science and Engineering, University of Science and Technology Beijing, 100083 Beijing (China); Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials, 100083 Beijing (China); Lejček, Pavel [Laboratory of Nanostructures and Nanomaterials, Institute of Physics, Academy of Sciences of the Czech Republic, Na Slovance 2, CZ-182 21 Prague 8 (Czech Republic); Song, Shenhua [Department of Materials Science and Engineering, Shenzhen Graduate School, Harbin Institute of Technology, Shenzhen 518055 (China); Schmitz, Guido [Institute of Materials Science, University of Stuttgart, Heisenbergstr. 3, 70569 Stuttgart (Germany); Meng, Ye [School of Materials Science and Engineering, University of Science and Technology Beijing, 100083 Beijing (China)

    2015-10-25

    Grain boundary (GB) segregation of P in 2.25Cr1Mo steel induced by elastic stress shows that the P equilibrium concentration, after reaching the non-equilibrium concentration maximum at critical time, returns to its initial thermal equilibrium level. This finding confirms the interesting phenomenon that the effect of elastic stress on GB segregation of P is significant in kinetics while slight in thermodynamics. Through extending the “pressure” in classical theory of chemical potential to the “elastic stress”, the thermodynamic effect of elastic stress on GB segregation is studied, and the relationship between elastic stress and segregation Gibbs energy is formulated. The formulas reveal that the difference in the segregation Gibbs energy between the elastically-stressed and non-stressed states depends on the excess molar volume of GB segregation and the magnitude of elastic stress. Model calculations in segregation Gibbs energy confirm that the effect of elastic stress on the thermodynamics of equilibrium GB segregation is slight, and the theoretical analyses considerably agree with the experimental results. The confirmation indicates that the nature of the thermodynamic effect is well captured. - Highlights: • GB segregation of P after stress aging returns to its initial thermal equilibrium level. • Relationship between elastic stress and segregation energy is formulated. • Thermodynamic effect relies on excess molar volume and magnitude of elastic stress. • Effect of elastic stress on Gibbs energy of GB segregation is estimated to be slight. • Complete theory of the effect of elastic stress on grain boundary segregation is setup.

  20. Air-Driven Segregation in Binary Granular Mixtures with Same Size but Different Densities

    Institute of Scientific and Technical Information of China (English)

    LU Chang-Hong; SHI Qing-Fan; YANG Lei; SUN Gang

    2008-01-01

    We investigate the segregation effect of binary granular mixtures with the same size but different densities under vibration at different air pressures. Our experiments show that the segregation state is seriously dependent on the air pressure and there is a new type of partially segregated state at high air pressure, which has the characteristic that the lighter grains tend to stay at the bottom and form a pure layer, while heavier grains and remained lighter ones tend to rise and to form a mixed layer on the top of the system. We redefine the order parameter to study the variation of the segregation effect with the air pressure and vibration parameter in detail. Finally, the mechanism of the air-driven segregation is illustrated by the faster acceleration due to the airflow through the granular bed for lighter particles.

  1. Bacterial chromosome organization and segregation.

    Science.gov (United States)

    Badrinarayanan, Anjana; Le, Tung B K; Laub, Michael T

    2015-01-01

    If fully stretched out, a typical bacterial chromosome would be nearly 1 mm long, approximately 1,000 times the length of a cell. Not only must cells massively compact their genetic material, but they must also organize their DNA in a manner that is compatible with a range of cellular processes, including DNA replication, DNA repair, homologous recombination, and horizontal gene transfer. Recent work, driven in part by technological advances, has begun to reveal the general principles of chromosome organization in bacteria. Here, drawing on studies of many different organisms, we review the emerging picture of how bacterial chromosomes are structured at multiple length scales, highlighting the functions of various DNA-binding proteins and the impact of physical forces. Additionally, we discuss the spatial dynamics of chromosomes, particularly during their segregation to daughter cells. Although there has been tremendous progress, we also highlight gaps that remain in understanding chromosome organization and segregation. PMID:26566111

  2. On the dynamics of segregation

    OpenAIRE

    Jofre-Monseny, Jordi; Dahlberg, Matz; Fredriksson, Peter

    2012-01-01

    Card et al (2008a) formalize a model of ethnic residential segregation where an ethnically mixed neighborhood is dynamically stable until its minority share reaches a threshold (the tipping point). Once the neighborhood has surpassed the tipping point, it will experience massive white flight. These authors propose methods to identify tipping points and, using population counts at the US Census tract level, find that tipping is a salient feature of neighborhood dynamics. The objective of this ...

  3. GRAIN BOUNDARY SEGREGATIONS AND HYDROGEN EMBRITTLEMENT

    OpenAIRE

    Aucouturier, M.

    1982-01-01

    The relation between grain boundary segregation and hydrogen embrittlement of metals may be discussed from two stand points : 1°) Hydrogen has a strong tendency to segregate in structure defects, among them, in grain boundaries. Hydrogen segregation controls the properties of hydrogenated materials in many cases (hydrogen diffusion, hydrogen induced cracking, electrical properties in semiconductors, etc) and more precisely their mechanical behaviour (embrittlement itself). 2°) The occurence o...

  4. Gender segregation : from birth to occupation

    OpenAIRE

    Ruiz-Castillo, Javier; Mora, Ricardo

    2003-01-01

    Most of the existing literature studies the gender segregation induced by occupational choices in the employed population. This paper also studies the segregation induced by age/education characteristics and labor market participation decisions in the population consisting of non-students of working age. The gender segregation index used, related to the entropy notion in information theory, is additively decomposable for any partition and it has a commutability property. The em...

  5. From particle segregation to the granular clock

    OpenAIRE

    Lambiotte, R.; Salazar, J. M.; Brenig, L.

    2005-01-01

    Recently several authors studied the segregation of particles for a system composed of mono-dispersed inelastic spheres contained in a box divided by a wall in the middle. The system exhibited a symmetry breaking leading to an overpopulation of particles in one side of the box. Here we study the segregation of a mixture of particles composed of inelastic hard spheres and fluidized by a vibrating wall. Our numerical simulations show a rich phenomenology: horizontal segregation and periodic beh...

  6. Social Exclusion: Residential Segregation in Bolivian Cities

    OpenAIRE

    George Gray-Molina; Wilson Jimenez; Ernesto Perez de Rada

    2002-01-01

    This study analyzes the impact of ethnic-based residential segregation on income and education outcomes in Bolivian cities. Three results stand out in the analysis. First, we find significant and negative segregation effects on income generation in both across-city and intra-city comparisons. Second, we find individual and neighborhood-level interactions between ethnicity and segregation to be significantly and negatively correlated with income and schooling attainment. Finally, we find posit...

  7. The Spatial Context of Residential Segregation

    OpenAIRE

    Roberto, Elizabeth

    2015-01-01

    Residential segregation is defined in a variety of ways to address a common concern: to what extent do social groups reside in separate or distinct places. The spatial pattern of segregation varies widely across cities, and distinct spatial patterns can be generated by different mechanisms and have different consequences for residents and their communities. However, the methods commonly employed to measure segregation ignore how a city is spatially organized. They do not take into account the...

  8. Segregation and Urban Unrest in Sweden

    OpenAIRE

    Malmberg, Bo; Eva, Andersson; Östh, John

    2013-01-01

    In 2009, Sweden experienced a wave of urban unrest concentrated in areas with large foreign-born populations. This episode was seen by many as reflecting a trend towards increased ethnically based residential segregation, in line with scholarly literatures that correlate inequality and rising segregation with increases in unrest or rebellion. In this paper, we analyze the empirical connection between ethnic residential segregation and episodes of urban unrest in Sweden. Unrest is measured by ...

  9. Socio-spatial lifestyles and segregation

    OpenAIRE

    Izhak, Schnell; Yoav, Benjamini

    1999-01-01

    The paper suggests an alternative index for socio-spatial segregation which emphasises agents’ segregation in everyday life. We argue that segregation should be studied for individual agents in respect to the spaces in which they perform their everyday life. The index refers both to the spatial and the social-interactive contexts of seven aspects (home, cluster of neighbouring homes, neighbourhood and city in the spatial context and friends, work and leisure activities in the social context) ...

  10. DIFFUSION AND EQUILIBRIUM SEGREGATION IN GRAIN BOUNDARIES : EFFECTS OF LARGE SEGREGATION

    OpenAIRE

    Bernardini, J.; Cabane, F.

    1985-01-01

    From recent experiments in binary and ternary solid solutions, we discuss the determination of grain boundary diffusion coefficients, some structural aspects of diffusion and segregation and the influence of segregation on impurity diffusion.

  11. From particle segregation to the granular clock

    Energy Technology Data Exchange (ETDEWEB)

    Lambiotte, R. [Physique Statistique, Plasmas et Optique Non-lineaire, Universite Libre de Bruxelles, Campus Plaine, Boulevard du Triomphe, Code Postal 231, 1050 Brussels (Belgium)]. E-mail: rlambiot@ulb.ac.be; Salazar, J.M. [Universite De Bougogne-LRRS UMR-5613 CNRS, Faculte des Sciences Mirande, 9 Av. Alain Savary, 21078 Dijon Cedex (France)]. E-mail: jmarcos@u-bourgogne.fr; Brenig, L. [Physique Statistique, Plasmas et Optique Non-lineaire, Universite Libre de Bruxelles, Campus Plaine, Boulevard du Triomphe, Code Postal 231, 1050 Brussels (Belgium)]. E-mail: lbrenig@ulb.ac.be

    2005-08-01

    Recently several authors studied the segregation of particles for a system composed of mono-dispersed inelastic spheres contained in a box divided by a wall in the middle. The system exhibited a symmetry breaking leading to an overpopulation of particles in one side of the box. Here we study the segregation of a mixture of particles composed of inelastic hard spheres and fluidized by a vibrating wall. Our numerical simulations show a rich phenomenology: horizontal segregation and periodic behavior. We also propose an empirical system of ODEs representing the proportion of each type of particles and the segregation flux of particles. These equations reproduce the major features observed by the simulations.

  12. A Social Network Analysis of Occupational Segregation

    DEFF Research Database (Denmark)

    Buhai, Ioan Sebastian; van der Leij, Marco

    We develop a social network model of occupational segregation between different social groups, generated by the existence of positive inbreeding bias among individuals from the same group. If network referrals are important for job search, then expected homophily in the contact network structure...... social welfare optima. Surprisingly, we find that socially optimal policies involve segregation....... induces different career choices for individuals from different social groups. This further translates into stable occupational segregation equilibria in the labor market. We derive the conditions for wage and unemployment inequality in the segregation equilibria and characterize first and second best...

  13. From particle segregation to the granular clock

    International Nuclear Information System (INIS)

    Recently several authors studied the segregation of particles for a system composed of mono-dispersed inelastic spheres contained in a box divided by a wall in the middle. The system exhibited a symmetry breaking leading to an overpopulation of particles in one side of the box. Here we study the segregation of a mixture of particles composed of inelastic hard spheres and fluidized by a vibrating wall. Our numerical simulations show a rich phenomenology: horizontal segregation and periodic behavior. We also propose an empirical system of ODEs representing the proportion of each type of particles and the segregation flux of particles. These equations reproduce the major features observed by the simulations

  14. Housing Systems and Ethnic Spatial Segregation

    DEFF Research Database (Denmark)

    Andersen, Hans Skifter; Andersson, Roger; Wessel, Terje;

    Residential spatial segregation is related to housing markets and housing policies. In this paper, ethnic segregation is compared across four Nordic capitals and explanations for the differences are examined by comparing the housing markets and housing policies of the countries. The housing markets...... composition of neighbourhoods. Ethnic segmentation of housing tenures thus contributes to segregation, but the effect is much dependent on how tenures are distributed across space. In one of the cities, the policy of neighbourhood tenure mix has resulted in a relatively low degree of segregation in spite of...

  15. Si segregation at Fe grain boundaries analyzed by ab initio local energy and local stress

    International Nuclear Information System (INIS)

    Using density-functional theory calculations combined with recent local-energy and local-stress schemes, we studied the effects of Si segregation on the structural, mechanical and magnetic properties of the Σ3(1 1 1) and Σ11(3 3 2) Fe GBs formed by rotation around the [1 1 0] axis. The segregation mechanism was analyzed by the local-energy decomposition of the segregation energy, where the segregation energy is expressed as a sum of the following four terms: the local-energy change of Si atoms from the isolated state in bulk Fe to the GB segregated state, the stabilization of replaced Fe atoms from the GB to the bulk, the local-energy change of neighboring Fe atoms from the pure GB to the segregated GB and the local-energy change of neighboring Fe atoms from the system of an isolated Si atom in the bulk Fe to the pure bulk Fe. The segregation energy and value of each term greatly depends on the segregation site and Si concentration. The segregation at interface Fe sites with higher local energies in the original GB configurations naturally leads to higher segregation-energy gains, while interface sites with lower local energies can lead to larger energy gains if stronger Si–Fe interactions occur locally in the final segregated configurations. The high Si concentration reduces the segregation-energy gain per Si atom due to the local-energy increases of Si atoms neighboring to each other or through the reduction in the number of stabilized Fe atoms per Si atom as observed in a Si dimer in bulk Fe. In the Si-segregated GBs, Si–Fe bonds enhance local Young’s moduli and tend to suppress the interface weakening, while the GB adhesion is slightly reduced. And Fe atoms contacting Si atoms have reduced magnetic moments, due to Si–Fe sp-d hybridization interactions. (paper)

  16. PARTICLE SEGREGATION IN FLUIDIZED BINARY-MIXTURES

    NARCIS (Netherlands)

    HOFFMANN, AC; JANSSEN, LPBM

    1993-01-01

    The particle segregation in fluidised beds consisting of different types of binary mixtures is shown to be governed by the same particle transport processes. The segregation behaviour of both ''different-density mixtures'' and ''equal-density mixtures'', two types of system which until now largely h

  17. Losing Ground: School Segregation in Massachuestts

    Science.gov (United States)

    Ayscue, Jennifer B.; Greenberg, Alyssa

    2013-01-01

    Though once a leader in school integration, Massachusetts has regressed over the last two decades as its students of color have experienced intensifying school segregation. This report investigates trends in school segregation in Massachusetts by examining concentration, exposure, and evenness measures by both race and class. First, the report…

  18. 17 CFR 32.6 - Segregation.

    Science.gov (United States)

    2010-04-01

    ... 17 Commodity and Securities Exchanges 1 2010-04-01 2010-04-01 false Segregation. 32.6 Section 32.6 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION REGULATION OF COMMODITY OPTION TRANSACTIONS § 32.6 Segregation. (a) Any person which accepts money, securities, or property from an...

  19. 49 CFR 176.708 - Segregation distances.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Segregation distances. 176.708 Section 176.708... Requirements for Radioactive Materials § 176.708 Segregation distances. (a) Table IV lists minimum separation... into account any relocation of cargo during the voyage. (e) Any departure from the...

  20. Ising, Schelling and Self-Organising Segregation

    CERN Document Server

    Stauffer, D

    2007-01-01

    The similarities between phase separation in physics and residential segregation by preference in the Schelling model of 1971 are reviewed. Also, new computer simulations of asymmetric interactions different from the usual Ising model are presented, showing spontaneous magnetisation (= self-organising segregation) and in one case a sharp phase transition.

  1. Measuring segregation: an activity space approach

    Science.gov (United States)

    Wong, David W. S.; Shaw, Shih-Lung

    2011-06-01

    While the literature clearly acknowledges that individuals may experience different levels of segregation across their various socio-geographical spaces, most measures of segregation are intended to be used in the residential space. Using spatially aggregated data to evaluate segregation in the residential space has been the norm and thus individual's segregation experiences in other socio-geographical spaces are often de-emphasized or ignored. This paper attempts to provide a more comprehensive approach in evaluating segregation beyond the residential space. The entire activity spaces of individuals are taken into account with individuals serving as the building blocks of the analysis. The measurement principle is based upon the exposure dimension of segregation. The proposed measure reflects the exposure of individuals of a referenced group in a neighborhood to the populations of other groups that are found within the activity spaces of individuals in the referenced group. Using the travel diary data collected from the tri-county area in southeast Florida and the imputed racial-ethnic data, this paper demonstrates how the proposed segregation measurement approach goes beyond just measuring population distribution patterns in the residential space and can provide a more comprehensive evaluation of segregation by considering various socio-geographical spaces.

  2. Residential Segregation: Challenge to White America.

    Science.gov (United States)

    Denton, Nancy A.

    1994-01-01

    Examines the problem of residential segregation and demonstrates that it is a problem of social structure. The author contends that residential segregation has affirmed the continued subordination of blacks in American society over the past 50 years. New leadership in the Department of Housing and Urban Development is viewed as a positive…

  3. Progressive segregation of the Escherichia coli chromosome

    DEFF Research Database (Denmark)

    Nielsen, Henrik Jørck; Youngren, Brenda; Hansen, Flemming G.;

    2006-01-01

    We have followed the fate of 14 different loci around the Escherichia coli chromosome in living cells at slow growth rate using a highly efficient labelling system and automated measurements. Loci are segregated as they are replicated, but with a marked delay. Most markers segregate in a smooth...

  4. UNUSUAL SEGREGATION BEHAVIOR OF BORON AND ITS EFFECT ON SEGREGATION OF SULFUR IN NICKEL

    OpenAIRE

    Ladna, B.; Birnbaum, H

    1988-01-01

    The co-segregation of B and S to the surface and grain boundaries of Ni was studied by SAES and SIMS. B showed an unusual segregation behavior wich resulted in the precipitation of Ni3B in the near surface layer and a continuous monolayer type B segregation at the grain boundary. The S segregation was not influenced by the presence of B and resulted in a uniform monolayer surface and grain boundary coverage. Analysis of hydrogen charged samples fractured in situ suggests that B segregated to ...

  5. An Economic Model of Friendship: Homophily, Minorities and Segregation

    OpenAIRE

    Sergio Currarini; Paolo Pin; Jackson, Matthew O.

    2007-01-01

    We develop a model of friendship formation that sheds light on segregation patterns observed in social and economic networks. Individuals come in different types and have type-dependent benefits from friendships; we examine the properties of a steady-state equilibrium of a matching process of friendship formation. We use the model to understand three empirical patterns of friendship formation: (i) larger groups tend to form more same-type ties and fewer other-type ties than small groups, (ii)...

  6. The Spatial Context of Residential Segregation

    CERN Document Server

    Roberto, Elizabeth

    2015-01-01

    Scholars have engaged in a longstanding debate about how best to measure residential segregation, and scores of indexes have been developed in response. However, the methods commonly employed are aspatial -- they summarize the characteristics of segregation patterns, such as concentration or clustering, but ignore their spatial features, such as how neighborhoods are spatially arranged. As a consequence, many studies find the same level of segregation whether a city has a patchwork of racial and ethnic enclaves, or is divided into large areas with little or no diversity. New methods have been developed to capture the spatial proximity of neighborhoods and the geographic scale of clustering. However, they lack a realistic measure of distance and do not accurately represent how segregation varies within cities. In this paper, I introduce a new method for studying the spatial context of residential segregation. I measure the distance between locations along city roads rather than in a straight line. Road distanc...

  7. On the Segregation of Dark Matter Substructure

    CERN Document Server

    Bosch, Frank C van den; Campbell, Duncan; Behroozi, Peter

    2015-01-01

    We present the first comprehensive analysis of the segregation of dark matter subhaloes in their host haloes. Using numerical simulations, we examine the segregation of twelve different subhalo properties with respect to both orbital energy and halo-centric radius (in real space as well as in projection). Subhaloes are strongly segregated by accretion redshift, which is an outcome of the inside-out assembly of their host haloes. Since subhaloes that were accreted earlier have experienced more tidal stripping, subhaloes that have lost a larger fraction of their mass at infall are on more bound orbits. Subhaloes are also strongly segregated in their masses and maximum circular velocities at accretion. We demonstrate that part of this segregation is already imprinted in the infall conditions. For massive subhaloes it is subsequently boosted by dynamical friction, but only during their first radial orbit. The impact of these two effects is counterbalanced, though, by the fact that subhaloes with larger accretion ...

  8. Simple queueing approach to segregation dynamics in Schelling model

    OpenAIRE

    Sobkowicz, Pawel

    2007-01-01

    A simple queueing approach for segregation of agents in modified one dimensional Schelling segregation model is presented. The goal is to arrive at simple formula for the number of unhappy agents remaining after the segregation.

  9. On the segregation of dark matter substructure

    Science.gov (United States)

    van den Bosch, Frank C.; Jiang, Fangzhou; Campbell, Duncan; Behroozi, Peter

    2016-01-01

    We present the first comprehensive analysis of the segregation of dark matter subhaloes in their host haloes. Using three different numerical simulations, and two different segregation strength indicators, we examine the segregation of 12 different subhalo properties with respect to both orbital energy and halocentric radius (in real space as well as in projection). Subhaloes are strongly segregated by accretion redshift, which is an outcome of the inside-out assembly of their host haloes. Since subhaloes that were accreted earlier have experienced more tidal stripping, subhaloes that have lost a larger fraction of their mass at infall are on more bound orbits. Subhaloes are also strongly segregated in their masses and maximum circular velocities at accretion. We demonstrate that part of this segregation is already imprinted in the infall conditions. For massive subhaloes, it is subsequently boosted by dynamical friction, but only during their first radial orbit. The impact of these two effects is counterbalanced, though, by the fact that subhaloes with larger accretion masses are accreted later. Because of tidal stripping, subhaloes reveal little to no segregation by present-day mass or maximum circular velocity, while the corresponding torques cause subhaloes on more bound orbits to have smaller spin. There is a weak tendency for subhaloes that formed earlier to be segregated towards the centre of their host halo, which is an indirect consequence of the fact that (sub)halo formation time is correlated with other, strongly segregated properties. We discuss the implications of our results for the segregation of satellite galaxies in galaxy groups and clusters.

  10. Legally White, Socially "Mexican": The Politics of De Jure and De Facto School Segregation in the American Southwest

    Science.gov (United States)

    Donato, Ruben; Hanson, Jarrod S.

    2012-01-01

    The history of Mexican American school segregation is complex, often misunderstood, and currently unresolved. The literature suggests that Mexican Americans experienced de facto segregation because it was local custom and never sanctioned at the state level in the American Southwest. However, the same literature suggests that Mexican Americans…

  11. RELATION BETWEEN ELECTROCHEMICAL REACTIVITY AND STRUCTURE OF GRAIN BOUNDARIES CORRELATED TO INTERGRANULAR SULFUR SEGREGATION IN ULTRA PURE NICKEL

    OpenAIRE

    Beaunier, L.; Vignaud, C.; Bouchet, D; Colliex, C.; Trebbia, P.

    1985-01-01

    In a ultra pure nickel doped with 8 and 16 ppm of sulfur, we have determined the kineticsand equilibrium state of segregated sulfur at grain boundaries by electrochemical corrosion test. The undoped nickel and the highest segregated specimen are observed in transmission electron microscopy in order to correlate the structural histogram with electrochemical reactivity study and analytical scanning transmission electron microscope experiments.

  12. Referral Hiring and Gender Segregation in the Workplace

    OpenAIRE

    Troy Tassier

    2008-01-01

    Segregation by type of work or discrimination are two common explanations for gender segregation in the workplace. A third, gender segregation due to referral hiring through segregated social networks, is less well explored. In this paper, I use an agent-based model of referral hiring to demonstrate that it could create high levels of gender segregation near those observed in data. But the model cannot account for all of the segregation observed. Eastern Economic Journal (2008) 34, 429–440. d...

  13. Surface segregation in nanoparticles from first principles: The case of FePt

    International Nuclear Information System (INIS)

    FePt nanoparticles are known to exhibit reduced L10 order with decreasing particle size. The phenomenon is addressed by investigating the thermodynamic driving forces for surface segregation using a local (inhomogeneous) cluster expansion fit to ab initio data. Subsequent Monte Carlo simulations reveal that first surface layer Pt segregation is compensated by Pt depletion in the second subsurface layer. This indicates that the core's ordered state is not affected by surface thermodynamics as much as previously thought.

  14. Declining Segregation of Same-Sex Partners: Evidence from Census 2000 and 2010.

    Science.gov (United States)

    Spring, Amy L

    2013-10-01

    Despite recent media and scholarly attention describing the "disappearance" of traditionally gay neighborhoods, urban scholars have yet to quantify the segregation of same-sex partners and determine whether declining segregation from different-sex partners is a wide-spread trend. Focusing on the 100 most populous places in the United States, I use data from the 2000 and 2010 Decennial Census to examine the segregation of same-sex partners over time and its place-level correlates. I estimate linear regression models to examine the role of four place characteristics in particular: average levels of education, aggregate trends in the family life cycle of same-sex partners, violence and social hostility motivated by sexual orientation bias, and representation of same-sex partners in the overall population. On average, same-sex partners were less segregated from different-sex partners in 2010 than in 2000, and the vast majority of same-sex partners lived in environments of declining segregation. Segregation was lower and declined more rapidly in places that had a greater percentage of graduate degree holders. In addition, segregation of female partners was lower in places that had a greater share of female partner households with children. These findings suggest that sexual orientation should be considered alongside economic status, race, and ethnicity as an important factor that contributes to neighborhood differentiation and urban spatial inequality. PMID:24187412

  15. Segregation practices in the management of low-level radioactive wastes

    International Nuclear Information System (INIS)

    A scoping study has been undertaken to determine the state-of-the-art of waste segregation technology as applied to the management of low-level waste (LLW). Present-day waste segregation practices were surveyed through a review of the recent literature and by means of personal interviews with personnel at selected facilities. Among the nuclear establishments surveyed were Department of Energy (DOE) laboratories and plants, nuclear fuel cycle plants, public and private laboratories, institutions, industrial plants, and DOE and commercially operated shallow land burial sites. These survey data were used to analyze the relationship between waste segregation practices and waste treatment/disposal processes, to assess the developmental needs for improved segregation technology, and to evaluate the costs and benefits associated with the implementation of waste segregation controls. For improved processing and disposal of LLW, it is recommended that waste segregation be practiced wherever it is technically feasible and cost-effective to do so. It is noted that LLW management practices are now undergoing rapid change such that the technology and requirements for waste segregation in the near future may differ significantly from those of the present day

  16. Modeling density segregation in granular flow

    Science.gov (United States)

    Xiao, Hongyi; Lueptow, Richard; Umbanhowar, Paul

    2015-11-01

    A recently developed continuum-based model accurately predicts segregation in flows of granular mixtures varying in particle size by considering the interplay of advection, diffusion and segregation. In this research, we extend the domain of the model to include density driven segregation. Discrete Element Method (DEM) simulations of density bidisperse flows of mono-sized particles in a quasi-2D bounded heap were performed to determine the dependence of the density driven segregation velocity on local shear rate, particle concentration, and a segregation length which scales with the particle size and the logarithm of the density ratio. With these inputs, the model yields theoretical predictions of density segregation patterns that quantitatively match the DEM simulations over a range of density ratios (1.11-3.33) and flow rates (19.2-113.6 cm3/s). Matching experiments with various combinations of glass, steel and ceramic particles were also performed which reproduced the segregation patterns obtained in both the simulations and the theory.

  17. Quantification of segregation dynamics in ice mixtures

    OpenAIRE

    Öberg, Karin I.; Fayolle, Edith C.; Cuppen, Herma M.; van Dishoeck, Ewine F.; Linnartz, Harold

    2009-01-01

    (Abridged) The observed presence of pure CO2 ice in protostellar envelopes is attributed to thermally induced ice segregation, but a lack of quantitative experimental data has prevented its use as a temperature probe. Quantitative segregation studies are also needed to characterize diffusion in ices, which underpins all ice dynamics and ice chemistry. This study aims to quantify the segregation mechanism and barriers in different H2O:CO2 and H2O:CO ice mixtures covering a range of astrophysic...

  18. Veil: A Wall of Segregation

    Directory of Open Access Journals (Sweden)

    Tayebeh Nowrouzi

    2015-08-01

    Full Text Available Moving behind the confines of the race has been the continuous efforts of African-Americans so as to reveal and confirm their true humanity and abilities to white race as well as their own race. African-Americans, Dubois posited, are shut out of the white America, inhabiting behind a vast veil which creates a deep division between the races. Veil is made of the fabric of racism interwoven thread by thread and imposed by white world. It is thrown discourteously and forcibly to the African-Americans whom their distorted images are imposed on them and their true humanity and identity are hidden behind the veil. This study overtakes to present how Loraine Hansberry, in her first and the most outstanding drama, A Raisin in the Sun examines the world within the veil. She demonstrated that Duboisian metaphoric veil is operating in the racist American society so that not only African-Americans are segregated physically and psychologically from the rest of the world but also are inflicted with obscurity of vision that are neither able to see themselves clearly nor be seen truly. On the other hand, it presents how the veil provides blacks with the second sight to observe and comprehend the racist nature of whites which is hidden and incomprehensible for them.

  19. Gender Segregated Labour Markets in the Baltics: What are Prevailing – Similarities or Differences?

    Directory of Open Access Journals (Sweden)

    Rein Vöörmann

    2009-11-01

    Full Text Available This paper focuses on men and women and the gender segregation of jobs in the Baltic countries. Based on the Estonian, Latvian and Lithuanian labour force survey data, a look is taken at the employment structure of men and women by industries and occupations, as well as at the question whether or not gender segregation in the labour market has been increased after the collapse of the communist systems in the region under consideration. Empirical data demonstrate that in respect to industrial gender segregation there is some increase in Estonia and Latvia, but not in Lithuania. Occupational gender segregation demonstrates more stability in all three Baltic States. Compared to the Western European countries, the main trend is towards bigger similarities.

  20. Residential Segregation in Southern Cities: 1970

    Science.gov (United States)

    And Others; Roof, Wade Clark

    1976-01-01

    Based on an analysis of the age, size, percent black, and occupational income differential in 32 southern cities, the findings show that age is still the strongest predictor of residential segregation. (Author)

  1. Demographic processes and ethnic residential segregation

    Directory of Open Access Journals (Sweden)

    Itzhak Omer

    1999-01-01

    Full Text Available This paper examines the involvement of demographic processes in the residential segregation of ethnic groups in an urban area. For this purpose, a two-part methodology has been employed. The first part comprises a conceptual framework which uses the concept of time–space resources as an analytical tool to clarify the structural constraints embedded in the changes in ethnic residential distribution. The second part comprises a simulation model of ethnic residential segregation. The model, which fits into the category of agent-based simulation models, serves as a tool for heuristic study. The methodology has been applied to examine the implications of fluctuations in ethnic group diffusion and the residential mobility rate on the majority–minority residential segregation, and on the internal ethnic segregation within the minority group.

  2. The Distribution of Segregation in Atlanta

    Science.gov (United States)

    Meade, Anthony

    1972-01-01

    A prediction from ecological theory relating the distribution of residential segregation between inner and outer zones of a metropolitan area to conditions of population growth, expansion, etc. was tested using 1960 data on the Atlanta standard metropolitan statistical area. (JM)

  3. Possible segregation caused by centrifugal titanium casting.

    Science.gov (United States)

    Watanabe, K; Okawa, S; Kanatani, M; Nakano, S; Miyakawa, O; Kobayashi, M

    1996-12-01

    The possibility of the segregation under solidification process using a centrifugal casting machine was investigated using an electron probe microanalyzer with elemental distribution map, line analysis and quantitative analysis. When a very small quantity of platinum was added to local molten titanium during the casting process, macroscopic segregation was observed under conditions of density difference of 0.1 g/cm3 at the most, confirming that the centrifugal force of the casting machine is extremely strong. When a Ti-6Al-4V alloy was cast, however, no macroscopic segregation was observed. The centrifugal force of the casting machine examined in the present study hardly results in the body-force segregation in this titanium alloy. PMID:9550020

  4. Modeling size segregation of bidisperse granular flow: the roles of segregation, advection, and diffusion

    OpenAIRE

    Fan, Yi; Schlick, Conor; Isner, Austin; Ottino, Julio; Umbanhowar, Paul; Richard, Lueptow

    2014-01-01

    Segregation of granular materials composed of different-sized particles has important repercussions in various industrial processes and natural phenomena, but predicting size segregation remains a challenging problem. To address this problem, we have developed a theoretical model that captures the interplay between advection, segregation, and diffusion in size bidisperse granular materials. The fluxes associated with these three driving factors depend on the underlying kinematics, whose chara...

  5. Gender Differences in the Effect of Residential Segregation on Workplace Segregation among Newly Arrived Immigrants

    OpenAIRE

    Tammaru, Tiit; Strömgren, Magnus; van Ham, Maarten; Danzer, Alexander M.

    2015-01-01

    Contemporary cities are becoming more and more diverse in population as a result of immigration. Research also shows that within cities residential neighborhoods are becoming ethnically more diverse, but that residential segregation has remained persistently high. High levels of segregation are often seen as negative, preventing integration of immigrants in their host society and having a negative impact on people's lives. Segregation research often focuses on residential neighborhoods, but i...

  6. Demographic processes and ethnic residential segregation

    OpenAIRE

    Itzhak Omer

    1999-01-01

    This paper examines the involvement of demographic processes in the residential segregation of ethnic groups in an urban area. For this purpose, a two-part methodology has been employed. The first part comprises a conceptual framework which uses the concept of time–space resources as an analytical tool to clarify the structural constraints embedded in the changes in ethnic residential distribution. The second part comprises a simulation model of ethnic residential segregation. The model, whic...

  7. Decentralization as a Cause of Spatial Segregation

    OpenAIRE

    Jasarovic Ema Alihodzic; Komatina Dragan; Zaric Sanja Paunovic

    2016-01-01

    City represents an incomplete dynamic process prone to the expansion with a causal link between urban expansion and socio-spatial segregation. The socio-spatial distribution in the city is mostly related to the increased social polarization and inequality. There is a clear connection between divided society and divided city: if society is divided, urban space must be divided. It is the question of the relations between the social inequalities on one hand, and spatial segregation on the other....

  8. Segregation isotherms at the surfaces of oxide

    International Nuclear Information System (INIS)

    A non-Arrhenius segregation isotherm is derived which includes the change in the heat of segregation with surface coverage due to impurity-impurity interactions. It is shown that a linear dependence of log(xs) on the reciprocal temperature, where xs is the surface atomic ratio, can derive either from a constant heat of segregation, i.e., Arrhenius behavior, or from a heat of segregation that varies as xs-1. This isotherm is then used to calculate the equilibrium surface coverages of Ca at the {001} surface of MgO, Mg at the {0001} surface of α-Al2O3, Y at the {1012} and {1 bar 120} surfaces of α-Al2O3, and Na at the {111} and {110} surfaces of Li2O from the calculated heats of segregation. Where possible, comparisons are made with experiment. The more useful operational definition of the heat of segregation, namely, that derived from the measured coverage or that defined atomistically and obtained by calculation, is discussed

  9. Radiation-induced segregation in titanium alloys

    International Nuclear Information System (INIS)

    Radiation-induced segregation (RIS) of V, Mo, Nb, Ta, Zr, and Sn in binary titanium alloys was investigated to test the solute size effect correlation in hcp alloys. Undersize Mo segregates weakly toward the sinks. Nb and Ta, which are slightly oversize in Ti, undergo little or no RIS. Oversize Zr solute in Ti segregates away from the sinks, whereas undersize Ti solute in Zr is enriched at sinks. All of these results are in accord with the solute size effect correlation. Surprisingly, Sn, which is significantly oversize in Ti, appears to segregate very little. The postirradiation annealing of Ti-3V and Ti-8Al-1V-1Mo confirmed that segregation of undersize V toward sinks is radiation-induced. Measurements of temperature and dose dependence in binary and complex alloys showed that the degree of V segregation has a maximum at proportional6000C and obeys parabolic growth kinetics in its early stages but probably saturates at a rather low dose (proportional0.8 dpa). (orig.)

  10. 28 CFR 541.21 - Conditions of disciplinary segregation.

    Science.gov (United States)

    2010-07-01

    ... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Conditions of disciplinary segregation... Conditions of disciplinary segregation. (a) Disciplinary segregation is the status of confinement of an... general population. Inmates housed in disciplinary segregation have significantly fewer privileges...

  11. What Should an Index of School Segregation Measure?

    Science.gov (United States)

    Allen, Rebecca; Vignoles, Anna

    2007-01-01

    The article aims to make a methodological contribution to the education segregation literature, providing a critique of previous measures of segregation used in the literature, as well as suggesting an alternative approach to measuring segregation. Specifically, the paper examines Gorard, Fitz and Taylor's finding that social segregation between…

  12. 41 CFR 109-1.5106 - Segregation of personal property.

    Science.gov (United States)

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Segregation of personal...-INTRODUCTION 1.51-Personal Property Management Standards and Practices § 109-1.5106 Segregation of personal...) The segregation of the property would materially hinder the progress of the work (i.e., segregation...

  13. Gender Segregation in the Spanish Labor Market: An Alternative Approach

    Science.gov (United States)

    del Rio, Coral; Alonso-Villar, Olga

    2010-01-01

    The aim of this paper is to study occupational segregation by gender in Spain, which is a country where occupational segregation explains a large part of the gender wage gap. As opposed to previous studies, this paper measures not only overall segregation, but also the segregation of several population subgroups. For this purpose, this paper uses…

  14. Segregation by thermal diffusion in granular shear flows

    OpenAIRE

    Garzó, Vicente; Reyes, Francisco Vega

    2010-01-01

    Segregation by thermal diffusion of an intruder immersed in a sheared granular gas is analyzed from the (inelastic) Boltzmann equation. Segregation is induced by the presence of a temperature gradient orthogonal to the shear flow plane and parallel to gravity. We show that, like in analogous systems without shear, the segregation criterion yields a transition between upwards segregation and downwards segregation. The form of the phase diagrams is illustrated in detail showing that they depend...

  15. Measuring Segregation: Basic Concepts and Extensions to Other Domains

    OpenAIRE

    Silber, Jacques

    2012-01-01

    This paper presents the main concepts used in measuring segregation. First it shows that the cardinal as well as the ordinal approach to the measurement of occupational segregation, when only two groups are considered (generally men and women), borrowed many ideas from the income inequality measurement literature. Second, it shows that more recent advances in segregation measurement, that were the consequence of an extension of segregation measures to the case of multi-group segregation and m...

  16. Industrial segregation of female and male workers in Spain

    OpenAIRE

    Olga Alonso-Villar; Coral del Río

    2009-01-01

    The aim of this paper is to study segregation in the Spanish labor market for both male and female workers, paying special attention to industrial segregation. As opposed to other studies, this article quantifies the segregation of each demographic group separately, rather than measuring overall segregation. For this purpose, it uses additively decomposable indices, together with local segregation curves, recently proposed in the literature, which allows us to go further in the empirical anal...

  17. A Measure of Segregation Based on Social Interactions

    OpenAIRE

    Echenique, Federico; Fryer, Roland

    2007-01-01

    We develop an index of segregation based on two premises: (1) a measure of segregation should disaggregate to the level of individuals, and (2) an individual is more segregated the more segregated are the agents with whom she interacts. We present an index that satisfies (1) and (2) and that is based on agents' social interactions: the extent to which blacks interact with blacks, whites with whites, etc. We use the index to measure school and residential segregation. Using detailed data on fr...

  18. A unified framework for Schelling's model of segregation

    International Nuclear Information System (INIS)

    Schelling's model of segregation is one of the first and most influential models in the field of social simulation. There are many variations of the model which have been proposed and simulated over the last forty years, though the present state of the literature on the subject is somewhat fragmented and lacking comprehensive analytical treatments. In this paper a unified mathematical framework for Schelling's model and its many variants is developed. This methodology is useful in two regards: firstly, it provides a tool with which to understand the differences observed between models; secondly, phenomena which appear in several model variations may be understood in more depth through analytic studies of simpler versions

  19. Correlation between segregation and cold cracking

    International Nuclear Information System (INIS)

    An attempt is made to find a correlation between segregation in ferritic base metal and the occurrence of cold cracking. Besides describing the mechanical and engineering properties and chemical composition of the segregated areas, the paper discusses their behaviour when welded over. Characteristics and models of crack development are presented using cold cracking found in various components as an example. Suitable measures for limiting the risk of the occurrence of cold cracking are increasing the pre-heating temperature, use of weld filler material with optimum dryness, and heat treatment directly following welding. (author)

  20. Scaling behaviour in size segregation ("Brazil Nuts")

    OpenAIRE

    Devillard, Pierre

    1990-01-01

    Using a previously introduced Monte Carlo method, due to Rosato, Prinz, Strandburg and Swendsen, we carry out in two dimensions numerical studies of size segregation, a phenomenon which occurs when a granular medium made of particles of different sizes is shaken. We propose a new scaling law relating the segregation velocity υ to the amplitude of shaking A and to the ratio R of the diameters of the small disks to the large disks. ForA larger than a critical amplitude Ac, a scaling law holds: ...

  1. Carbon Segregation of Bearing Steel Concasting Billet

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The formation mechanism of “white band” and central carbon segregation of high-carbon Cr bearing steel concasting billets are discussed in this paper. The maximum oxygen content in the steel produced by concasting process was 13x10-6 with an average oxygen content of 9.3x 10-6.Comparison of metallurgical quality and fatigue property between the concasting steel (CC) andingot casting steel (IC) showed that the carbon segregation (C/C0) in former steel was 0.92~1.10and its fatigue life was equal to that of the latter steel.

  2. Chromosome segregation: learning to let go.

    Science.gov (United States)

    Higgins, Jonathan M G

    2013-10-01

    To ensure accurate chromosome segregation, cohesion between sister chromatids must be released in a controlled manner during mitosis. A new study reveals how distinct centromere populations of the cohesin protector Sgo1 are regulated by microtubule attachments, cyclin-dependent kinases, and the kinetochore kinase Bub1. PMID:24112985

  3. Segregation--The Act of Sequestering

    Science.gov (United States)

    Foster, Charlotte

    2011-01-01

    In this article, the author points out that there are many reasons why self-segregation takes place. For example: People with motorcycle interests may choose to hang out with other bikers. A group of bikers may have a common interest but can be as diverse as a doctor that is a biker or a janitor that is into biking. Formally educated people may…

  4. 49 CFR 176.83 - Segregation.

    Science.gov (United States)

    2010-10-01

    ... Federal Register citations affecting § 176.83, see the List of CFR Sections Affected, which appears in the... 49 Transportation 2 2010-10-01 2010-10-01 false Segregation. 176.83 Section 176.83 Transportation..., DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS CARRIAGE BY VESSEL General...

  5. Diversity, Racial Threat and Metropolitan Housing Segregation

    Science.gov (United States)

    DeFina, Robert; Hannon, Lance

    2009-01-01

    Previous studies have shown that as the percent black or percent Hispanic grows, that group's residential segregation from whites tends to increase as well. Typically, these findings are explained in terms of white discriminatory reaction to the perceived threat associated with minority population growth. The present analysis examines whether…

  6. Is Racial Segregation Changing in Charter Schools?

    Science.gov (United States)

    Lee, Jin; Lubienski, Christopher

    2011-01-01

    Charter schools embody the theoretical potential to promote integration since they can draw students from across district boundaries that often reflect segregated residential patterns. While a number of studies have examined overall racial composition of charter schools, virtually no attention has been paid to how charter school enrollment…

  7. Field induced phase segregation in ferrofluids

    NARCIS (Netherlands)

    Kooij, E.S.; Galca, A.C.; Poelsema, B.

    2008-01-01

    We study the phase segregation in magnetite ferrofluids under the influence of an external magnetic field. A phase with lower nanoparticle density and corresponding higher optical transmission is formed in the bottom of a glass cell in the presence of only a very modest magnetic field gradient (smal

  8. Interfacial segregation in perovskites. Part 1

    International Nuclear Information System (INIS)

    Based on thermodynamic principles a theory for equilibrium interfacial segregation is proposed for perovskite materials, and this theory is applied to BaTiO3. An approach developed by Frenkel and refined by Kliewer and Koehler is extended to undoped ternary oxide materials such as BaTiO3. The approach uses regular solution approximations and considers space charge effects as the major driving force for segregation. The analysis based on this model indicates the presence of a negative space charge potential (-0.1 V at 800 degrees C) at the surface of pure BaTiO3. The model also predicts cation enrichment at the interface. The thickness of the space charge layer decreases with increasing temperature, and calculated values agree well with experimental results. Since both elastic and electrostatic driving forces are important for dopant/impurity segregation, an approach where the grain boundary is considered to be a two-dimensional phase, in equilibrium with the three-dimensional phase of the grain, proves useful. Solving for the impurity/dopant segregation ratio is case specific and requires knowledge of the charge neutrality conditions as well as the strain energy contribution

  9. Social Consequences of Economic Segregation

    OpenAIRE

    Yoonseok Lee, Donggyun Shin, Kwanho Shin

    2013-01-01

    The empirical literature has not been successful in generating robust results for a positive relationship between income inequality and social unrest outcomes such as crime and suicide. This paper questions the use of standard income inequality measures (e.g., Gini coefficient) in such studies and shows that income-mobility-based measures are effective in explaining outcomes of social unrest. Analyses of Korean and the United States region-byyear data suggest that crime and suicide rates are ...

  10. Fluctuation effects in phase segregation

    International Nuclear Information System (INIS)

    The excess specific heat observed above the phase separation temperature in solid mixtures of 3He and 4He is attributed to the fluctuations that represent the symmetry of the condensing state. In a 3He rich solid the fluctuations of the 4He rich phase are 2-dimensional while in an even mixture they are 3-dimensional, the characteristic length scale is approximately the interparticle spacing

  11. Measuring Trends in Segregation: Three Dimensions, Three Measures.

    Science.gov (United States)

    Stearns, Linda Brewster; Logan, John R.

    1986-01-01

    Three commonly used measures of segregation (index of dissimilarity, p* interaction probabilities, and the correlation ratio) reflect three conceptually distinct aspects of racial residential segregation. The results of empirical studies will depend on the measure chosen. (Author/KH)

  12. Control on Housing Segregation:Housing Modes and Public Policies

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    <正>1. Housing segregation:advocating or controlling?The phenomenon of housing segregation has become more and more obvious in Chinese cities in recent years; however, there is no agreement on whether it should

  13. What Drives Racial Segregation? New Evidence Using Census Microdata

    OpenAIRE

    Bayer, Patrick; McMillan, Robert; Rueben, Kim

    2003-01-01

    This paper sheds new light on the forces that drive residential segregation on the basis of race, assessing the extent to which across-race differences in other household characteristics can explain a significant portion of observed racial segregation. The central contribution of the analysis is to provide a transparent new measurement framework for understanding segregation patterns. This framework allows researchers to characterize patterns of segregation, to decompose them in meaningful wa...

  14. Segregation phases in a vibrated binary granular layer

    OpenAIRE

    Reis, P. M.; Ehrhardt, G.; Mullin, T.

    2003-01-01

    We present the results of an experimental study of patterned segregation in a horizontally shaken shallow layer of a binary mixture of dry particles. As the compacity, $C$, of the mixture was increased, the evolution of three distinct phases was observed. We classify them as binary gas, segregation liquid and segregation crystal phases using macroscopic and microscopic measures. The binary gas to segregation liquid transition is consistent with a continuous phase transition and includes the c...

  15. Occupational Gender Segregation in the Czech Republic (in English)

    OpenAIRE

    Štìpán Jurajda; Michal Franta

    2007-01-01

    The authors use labor force survey data to provide a detailed description and an international comparison of the level and structure of occupational gender segregation in the Czech Republic during 1994–2004. Based on 1999 data, they find Czech occupational segregation to be close to the EU average, with the exception of young, highly educated Czech workers, who faced relatively high segregation. However, segregation has declined rapidly for young workers since 1999, mainly due to the increase...

  16. Tipping and Residential Segregation: A Unified Schelling Model

    OpenAIRE

    Zhang, Junfu

    2009-01-01

    This paper presents a Schelling-type checkerboard model of residential segregation formulated as a spatial game. It shows that although every agent prefers to live in a mixed-race neighborhood, complete segregation is observed almost all of the time. A concept of tipping is rigorously defined, which is crucial for understanding the dynamics of segregation. Complete segregation emerges and persists in the checkerboard model precisely because tipping is less likely to occur to such residential ...

  17. Residential Segregation Effects on Poor’s Opportunities in Chile

    OpenAIRE

    Osvaldo Larrañaga Jiménez; Claudia Sanhueza Riveros

    2007-01-01

    This paper aims to identify whether or not the spatial concentration of poverty –also called economic residential segregation- affects the opportunities of the poor in Chile. Residential segregation is understood as the concentration particular population groups in determined geographical areas within cities. To identify the effects of segregation we use a panel of cross sections of the Casen household surveys, although the measures of segregation are computed from the Census data. The result...

  18. Not Just Urban Policy: Suburbs, Segregation, and Charter Schools

    Science.gov (United States)

    Frankenberg, Erica; Siegel-Hawley, Genevieve

    2012-01-01

    As the charter school sector expands rapidly with federal support amid on-going diversification and growing segregation among traditional public school students, this article examines existing patterns of segregation in charter schools. Prior research has demonstrated that charter schools are substantially more segregated than our already…

  19. 46 CFR 151.13-5 - Cargo segregation-tanks.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Cargo segregation-tanks. 151.13-5 Section 151.13-5... CARRYING BULK LIQUID HAZARDOUS MATERIAL CARGOES Cargo Segregation § 151.13-5 Cargo segregation—tanks. (a... and list the various degrees of segregation required. Paragraphs and (2) of this section explain...

  20. Segregation of Granular Mixtures in a Rotating Drum

    OpenAIRE

    Puri, Sanjay; Hayakawa, Hisao

    1999-01-01

    We formulate a phenomenological model for the segregation of binary mixtures of rough and smooth granular materials in a rotating drum. Our model successfully replicates a range of experimental behaviours, e.g., rapid radial segregation; slow axial segregation; and nonuniform radial structure of axial bands. We present some analytical results and detailed numerical results for our model.

  1. 49 CFR 176.145 - Segregation in single hold vessels.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Segregation in single hold vessels. 176.145 Section 176.145 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS... VESSEL Detailed Requirements for Class 1 (Explosive) Materials Segregation § 176.145 Segregation...

  2. What is the primary source of the morphological segregation?

    OpenAIRE

    Andreon, S.

    1997-01-01

    In Coma and two other clusters of galaxies the primary morphological segregation is the one with respect to a privileged direction. Only when this segregation is not considered it appears that the morphological types are segregated in density or in clustercentric distance.

  3. 27 CFR 24.27 - Segregation of operations.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Segregation of operations. 24.27 Section 24.27 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU... Segregation of operations. The appropriate TTB officer may require the proprietor to segregate...

  4. Residential segregation of socioeconomic variables and health indices in Iran

    Directory of Open Access Journals (Sweden)

    Seyed Saeed Hashemi Nazari

    2013-01-01

    Conclusions: Correlation of segregation of determinants of socioeconomic status with segregation of health indices is an indicator of existence of hot zones of health problems across some provinces. Further studies using multilevel modeling and individual data in health outcomes at individual level and segregation measures at appropriate geographic levels are required to confirm these relations.

  5. Segregation and preterm birth: The effects of neighborhood racial composition in North Carolina

    Science.gov (United States)

    Epidemiologic research suggests that racial segregation is associated with poor health among blacks in the United States (US). We used geocoded birth records and US census data to investigate whether neighborhood-level percent black is associated with preterm birth (PTB) for blac...

  6. A Status Quo of Segregation: Racial and Economic Imbalance in New Jersey Schools, 1989-2010

    Science.gov (United States)

    Flaxman, Greg

    2013-01-01

    New Jersey has a curious status regarding school desegregation. It has had the nation's most venerable and strongest state law prohibiting racially segregated schooling and requiring racial balance in the schools whenever feasible. Yet, it simultaneously has had one of the worst records of racially imbalanced schools. Against the legal and…

  7. Miles to Go: A Report on School Segregation in Virginia, 1989-2010

    Science.gov (United States)

    Siegel-Hawley, Genevieve

    2013-01-01

    Virginia has a long and complicated history with school desegregation efforts. It is a state that can lay claim both to advancing the goals of "Brown v. Board of Education" and to impeding them. Over the years, this history has helped shape contemporary patterns of school segregation across Virginia and in her major metropolitan areas. This report…

  8. Implications of Income-Based School Assignment Policies for Racial School Segregation

    Science.gov (United States)

    Reardon, Sean F.; Yun, John T.; Kurlaender, Michal

    2006-01-01

    A number of public school districts in the United States have adopted income-based integration policies--policies that use measures of family income or socioeconomic status--in determining school assignment. Some scholars and policymakers contend that such policies will also reduce racial segregation. In this article this assumption is explored by…

  9. "Jeesis Is Alive! He Is the King of Australia": Segregated Religious Instruction, Child Identity and Exclusion

    Science.gov (United States)

    Byrne, Cathy Jane

    2012-01-01

    Religious categorisation occurs at enrolment in Australian state-run (public) primary schools, with children segregated into religious instruction classes during their first week. Lesson content has no government oversight and, in some schools, options are limited to Christianity. The effect of this categorisation on children's attitudes to…

  10. Generative Models of Segregation: Investigating Model-Generated Patterns of Residential Segregation by Ethnicity and Socioeconomic Status

    OpenAIRE

    Fossett, Mark

    2011-01-01

    This paper considers the potential for using agent models to explore theories of residential segregation in urban areas. Results of generative experiments conducted using an agent-based simulation of segregation dynamics document that varying a small number of model parameters representing constructs from urban-ecological theories of segregation can generate a wide range of qualitatively distinct and substantively interesting segregation patterns. The results suggest how complex, macro-level ...

  11. Potensi Kurkumin dan Pentagamavunon-0 sebagai Anti Viral Dengue - 2

    Directory of Open Access Journals (Sweden)

    Dewi Marbawati

    2015-07-01

    Full Text Available AbstractMore than 40% of the world's population who live in tropical and subtropical regions at risk for dengue infection. Specific and effective antiviral therapies to treat dengue infection has not been found yet. Many researches proved that curcumin has preventive activity againts viruses, such as vasicular stomatis (VSV, HSV 1 and 2, parainfluenza-3, reovirus-1, feline corona virus, feline herpes virus. Curcumin also known to perform the inhibition of ubiquitin - proteasome system that decreasethe production of Japanese encephalitis in neuroblastoma cells. Pentagamavunon-0 (PGV-0 is expected to have better activity than curcumin. This study aims to determine the cytotoxic effect andthe potential of curcumin and PGV-0 as antiviral Dengue-2 on vero cells. Including experimental study. Cytotoxic test performed to obtain a safe concentration of curcumin and PGV-0 on vero cells followed by antiviral test using immunocytochemistry SBPC (Streptavidin Biotin Peroxidase Complex. The results showed that the safe concentrations for curcumin is 6.25 ppm and PGV-0 is 1.5625 ppm based on cytotoxic test to vero cell. The positive rate from Immunocytochemistry test showed that no significant difference between curcumin and PGV-0 treatment. However, when compared with the positive control results are significantly different. We concluded both curcumin and PGV-0 can reduce the positive rate caused Dengue-2 infection at one day incubation.Keywords : Dengue-2, curcumin, pentagamavunon-0 (PGV-0, ImmunocytochemistryAbstrakLebih dari 40 % populasi dunia yang tinggal di daerah tropis dan subtropis mempunyai risiko untuk terjangkit infeksi Dengue. Terapi yang spesifik dan efektif untuk mengobati infeksi Dengue belum ditemukan. Kurkumin terbukti memiliki aktivitas preventif terhadap beberapa virus, antara lain:vasicular stomatis (VSV, HSV 1 dan 2, parainfluenza-3, reovirus-1, feline corona virus, feline herpes virus. Kurkumin juga diketahui mampu melakukan penghambatan sistem ubiquitin-proteasome yang menyebabkan penurunan produksi Japanese ensefalitis dari sel neuroblastoma yang sebelumnya terinfeksi. Pentagamavunon-0 (PGV-0 diperkirakan memiliki aktivitas lebih baik daripada kurkumin. Penelitian ini bertujuan untuk mengetahui efek sitotoksik dan mengetahui potensi antiviral Dengue-2 dari kurkumin dan PGV-0 pada sel vero. termasuk penelitian eksperimental. Uji sitotoksik dilakukan untuk mendapatkan konsentrasi yang aman dari kurkumin dan PGV-0 terhadap sel vero dilanjutkan dengan uji antiviral melalui imunositokimia SBPC (Streptavidin Biotin Peroxidase Complex. Hasil uji sitotoksik menunjukkan konsentrasi yang aman terhadap sel vero adalah 6,25 ppm untuk kurkumin dan 1,5625 ppm untuk PGV-0. Perhitungan positive rate dari uji imunositokimia pada sel vero yang diinfeksi Dengue-2 inkubasi 1 hari dan diberi kurkumin dan PGV-0 adalah tidak berbeda nyata, namun jika dibandingkan dengan kontrol positifnya hasilnya berbeda nyata. Disimpulkan baik kurkumin maupun PGV-0 mampu menurunkan positive rate akibat infeksi Dengue-2 inkubasi satu hari.Kata kunci : Dengue-2, kurkumin, pentagamavunon-0 (PGV-0, imunositokimia

  12. Immigrant residential segregation in U.S. metropolitan areas, 1990-2000.

    Science.gov (United States)

    Iceland, John; Scopilliti, Melissa

    2008-02-01

    This paper examines the extent of spatial assimilation among immigrants of different racial and ethnic origins. We use restricted data from the 1990 and 2000 censuses to calculate the levels of dissimilarity by race and Hispanic origin, nativity, and year of entry, and then run multivariate models to examine these relationships. The findings provide broad support for spatial assimilation theory. Foreign-born Hispanics, Asians, and blacks are more segregated from native-born non-Hispanic whites than are the U.S.-born of these groups. The patterns for Hispanics and Asians can be explained by the average characteristics of the foreign-born that are generally associated with higher levels of segregation, such as lower levels of income, English language ability, and home ownership. We also find that immigrants who have been in the United States for longer periods are generally less segregated than new arrivals, and once again, much of this difference can be attributed to the characteristics of immigrants. However, patterns also vary across groups. Levels of segregation are much higher for black immigrants than for Asian, Hispanic, and white immigrants. In addition, because black immigrants are, on average, of higher socioeconomic status than native-born blacks, such characteristics do not help explain their very high levels of segregation. PMID:18390292

  13. SEGREGATION IN HSLA STEELS FOR SOUR SERVICE: AN EVALUATION USING COMPUTATIONAL THERMODYNAMICS

    Directory of Open Access Journals (Sweden)

    André Luiz Vasconcellos da Costa e Silva

    2014-03-01

    Full Text Available The amount, type and distribution of non-metallic inclusions as well as the solidification segregation, which influences inclusion type and distribution, have great influence on the performance of High Strength Low Alloy (HSLA steels used in sour service in the oil industry. The effects of manganese, both on segregation and on steel cleanness have been studied through experiments and, to a lesser extent, through mathematical modeling of solidification. However, the effect of some other relevant elements added to these steels, in special those effects caused by solidification segregation, have not been extensively studied. In the present work, the extent of segregation and the probable effect on inclusion distribution of the main elements in HSLA steels used in sour service are evaluated through different computational thermodynamic models. In particular, two limiting cases bound the comparison: equilibrium solidification and the Scheil model, in which no homogenization in the solid phase is assumed. Special attention is given to silicon. For relevant compositions, models considering solid and liquid state diffusion are used. The results are compared with experimental data available for some steel compositions and serve as basis for a first evaluation of the alloy design strategy currently applied to these steels, from the point of view of segregation and internal cleanness.

  14. Investigation of segregation for AlxIn1-x liquid binary alloys

    International Nuclear Information System (INIS)

    Segregation of AlxIn1-x liquid binary alloys is systematically investigated from the energetic point of view using the electronic theory of metals. The free energy of mixing is calculated at different thermodynamic states characterized by temperatures for the full range of concentration by using the perturbation approach. The interionic interaction is described by a local pseudopotential. This study enables us to predict the correct miscibility gap as well as critical temperature (T=1160 K) and critical concentration (x=0.5) of segregation for the concerned alloys. These results agree well with available experimental data. Most importantly, results of our calculations have precisely identified for the first time that, the volume dependent term of the energy of mixing is mostly responsible for the total energy of mixing to be positive, which is one of the most significant indicators of segregation of liquid metals in binary alloys

  15. Collection and Segregation of Radioactive Waste. Principals for Characterization and Classification of Radioactive Waste

    International Nuclear Information System (INIS)

    Radioactive wastes are generated by all activities which utilize radioactive materials as part of their processes. Generally such activities include all steps in the nuclear fuel cycle (for power generation) and non-fuel cycle activities. The increasing production of radioisotopes in a Member State without nuclear power must be accompanied by a corresponding development of a waste management system. An overall waste management scheme consists of the following steps: segregation, minimization, treatment, conditioning, storage, transport, and disposal. To achieve a satisfactory overall management strategy, all steps have to be complementary and compatible. Waste segregation and minimization are of great importance mainly because they lead to cost reduction and reduction of dose commitments to the personnel that handle the waste. Waste characterization plays a significant part in the waste segregation and waste classification processes, it implicates required waste treatment process including the need for the safety assessment of treatment conditioning and storage facilities

  16. Time scale of entropic segregation of flexible polymers in confinement: Implications for chromosome segregation in filamentous bacteria

    OpenAIRE

    Arnold, Axel; Jun, Suckjoon

    2007-01-01

    We report molecular dynamics simulations of the segregation of two overlapping chains in cylindrical confinement. We find that the entropic repulsion between the chains can be sufficiently strong to cause segregation on a time scale that is short compared to the one for diffusion. This result implies that entropic driving forces are sufficiently strong to cause rapid bacterial chromosome segregation.

  17. From Schelling to Schools : A comparison of a model of residential segregation with a model of school segregation

    NARCIS (Netherlands)

    Stoica, Victor; Flache, Andreas

    2014-01-01

    We address theoretically whether and under what conditions Schelling's celebrated result of 'self-organized' unintended residential segregation may also apply to school segregation. We propose here a computational model of school segregation that is aligned with a corresponding Schelling-type model

  18. Segregation of polymers in confined spaces

    International Nuclear Information System (INIS)

    We investigate the motion of two overlapping polymers confined in a 2D box. A statistical model is constructed using blob-free-energy arguments. We find spontaneous segregation under the condition L > R∥, and mixing under L < R∥, where L is the length of the box and R∥ is the polymer extension in an infinite slit. The segregation time (τ) is determined by solving a mean first-passage time problem and by performing Monte Carlo simulations. Both show a minimum in τ as a function of L. Although our results are restricted to 2D, the basic mechanism of competition between entropy and confinement leading to the minimum is suggestive of an evolutionary driving force for size selection. (paper)

  19. Thermal segregation beyond Navier-Stokes

    International Nuclear Information System (INIS)

    A dilute suspension of impurities in a low-density gas is described by the Boltzmann and Boltzman-Lorentz kinetic theories. Scaling forms for the species distribution functions allow the determination of the space dependence of the hydrodynamic fields without restriction to small thermal gradients or Navier-Stokes hydrodynamics. The thermal diffusion factor characterizing segregation is identified in terms of collision integrals as a function of the mechanical properties of the particles and the temperature gradient. An evaluation of the collision integrals using Sonine polynomial approximations is discussed. The conditions for segregation both along and opposite to the temperature gradient are obtained and contrasted with the leading order Navier-Stokes approximation.

  20. Distribution and segregation of dissolved elements in pipeline slab

    Institute of Scientific and Technical Information of China (English)

    Jianhua Liu; Yanping Bao; Xian Dong; Taiquan Li; Yi Ren; Shuai Zhang

    2007-01-01

    The chemical composition in a cross section of a high grade pipeline slab was measured point by point (in a scale of 1 μm)using original position statistic distribution analysis (OPA). The result indicated that negative segregation strips of Si, Mn, Mo, Ni, Cr,Nb, Cu, Ti, and V exist in the two sides 24 mm away from the central line, with a width of 8-12 mm, Negative segregation inside the central line is more severe than that outside the central line, and the highest positive segregation of the elements appears closely by the inner sides of the negative segregation strips. No obvious negative segregation strip of S and P is found. Segregation of the elements in the central area is higher than that in the outer and inner arc areas. The segregation of C, Ti, S, and P is high and that of Cr, Cu, Si, and Mn is low in the slab.

  1. Evaluating segregation in granular filters for earth dams

    Energy Technology Data Exchange (ETDEWEB)

    Sutherland, K. [Cambridge Univ., Cambridge (United Kingdom); Grabinsky, M. [Toronto Univ., ON (Canada)

    2003-07-01

    This paper presented some case studies to illustrate the relationship between seepage problems encountered with earth dams and segregation of the dams' granular filters during construction. A literature review of segregation mechanisms was presented along with a laboratory investigation. The case studies showed that the current understanding of the impact of a given degree of segregation is relatively poor. The literature reveals that although segregation mechanisms are identified and analyzed, very few are likely to be predominant during earth dam construction. Laboratory studies show that a mathematical relationship can be established between the filter's grain size distribution curve and the potential degree of segregation. Therefore, a mathematical relationship can also be established with the potential for adverse dam performance. The authors proposed a field procedure which allows for the monitoring of segregation during construction by contractors and engineers. It also helps in deciding whether any segregated zones require replacement. 5 refs., 7 figs.

  2. Segregation by thermal diffusion in granular shear flows

    International Nuclear Information System (INIS)

    Segregation by thermal diffusion of an intruder immersed in a sheared granular gas is analyzed from the (inelastic) Boltzmann equation. Segregation is induced by the presence of a temperature gradient orthogonal to the shear flow plane and parallel to gravity. We show that, like in analogous systems without shear, the segregation criterion yields a transition between upwards segregation and downwards segregation. The form of the phase diagrams is illustrated in detail showing that they depend sensitively on the value of gravity relative to the thermal gradient. Two specific situations are considered: (i) absence of gravity and (ii) homogeneous temperature. We find that both mechanisms (upwards and downwards segregation) are stronger and more clearly separated when compared with segregation criteria in systems without shear

  3. Applying Fixed Effects to Hierarchical Segregation Models

    OpenAIRE

    Dina Shatnawi; Ronald Oaxaca; Michael Ransom

    2011-01-01

    This paper expands the empirical implementation of hierarchical segregation models to allow for the use of panel methods. We use firm level data collected between 1977 and 1985 from a regional grocery store that faced a title VII class-action lawsuit over gender discrimination much the same as Wal-Mart and Costco. Special problems arise in implementing decompositions in a fixed effects and random effects setting, especially when analyzing wage-level differences. We develop a variation of wage...

  4. Radiation effects on segregating seed in rice

    International Nuclear Information System (INIS)

    Seeds of segregating lines selected from dES treated M2 populations of rice were irradiated with gamma rays with a view to enhance the variabiity and thus selection parameter. Seedling and mature plant parameters and frequency of dividing cells showed reduction upon treatment. Very high frequency of chromosomal interchanges including rare cases of those involving the two nucleolar chromosomes and plants with 13 II were recorded. Several types of desirable morphological mutants were isolated. 7 refs., 3 tables. (author)

  5. Functional Segregation of the Entopallium in Pigeons

    OpenAIRE

    Robert G Cook; Patton, Tadd B.; Shimizu, Toru

    2013-01-01

    In birds, the entopallium is the primary telencephalic target of the major visual ascending route called the tectofugal pathway. Often functionally compared to the primate geniculo-striate pathway and its subsequent telencephalic (cortical) regions, the latter processes visual information in a parallel fashion in terms of anatomy, physiology, and function. Little is known, however, about the exact mechanism of whether or how information is segregated or integrated in the avian tectofugal path...

  6. Segregation analysis of schizophrenia and related disorders.

    OpenAIRE

    Risch, N; Baron, M

    1984-01-01

    Segregation analysis was applied to 79 nuclear families ascertained through chronic schizophrenic probands. Analysis was performed on the diagnosis of schizophrenia alone and on schizophrenia and schizotypal personality disorder (milder phenotype) combined. The models used were the transmission probability model and the mixed model. Because the disease is associated with reduced fertility, all likelihoods were calculated conditional on parental phenotypes. However, compatibility of the mating...

  7. Biased DNA Segregation during Stem Cell Division

    OpenAIRE

    Anversa, Piero; Leri, Annarosa; Kajstura, Jan

    2012-01-01

    Adult skeletal muscle stem cells are a heterogeneous cell population characterized by a small subset of undifferentiated cells that express at high level the paired/homeodomain gene Pax7. This category of satellite cells divides predominantly by asymmetric chromatid segregation generating a daughter cell that carries the mother DNA and retains stem cell property, and a daughter cell that inherits the newly-synthesized DNA and acquires the myocyte lineage.1

  8. Segregation patterns in gas-fluidized systems

    OpenAIRE

    Gilbertson, M.A.; Eames, I

    2001-01-01

    The formation of segregation patterns in initially homogeneous, fluidized, binary mixtures of particles has been studied. The adjustment of the bed depends on the proportions of fine and coarse particles in the mixture and the gas flow rate relative to the minimum fluidization velocities of the two components. The particles are immobile until the gas flow rate is sufficiently large to fluidize the mixture of particles. When the gas how rate exceeds this critical value, alternating vertical ba...

  9. On impurity segregation on dislocations in metals

    OpenAIRE

    Netchaev, Yu.; Mukhina, L.

    1993-01-01

    Thermodynamic and crystallo-chemistry considerations are given about the possibility of existing linear distribution laws for some impurities in metals between bulk solution and near-dislocation segregation regions (NDSR) with composition and structure close to the corresponding intermetallic compound. The solutions of Fe in Al are considered. NDSR composition can be close to FeAl3. The experimental data on the solubilities are treated within the model developed to determine the effective bin...

  10. Sexual Segregation in Iberian Noctule Bats

    OpenAIRE

    Ibáñez, Carlos; Guillén, Antonio; Agirre-Mendi, Pablo T.; Juste, Javier; Schreur, Godfried; Cordero, Ana I.; Popa-Lisseanu, Ana G.

    2009-01-01

    Sexual segregation during the breeding season is common in many temperate bat species, and may be related to sex-specific thermoregulatory, microclimatic, or energetic requirements. We compiled capture data for 3 species of Nyctalus (noctule bats) obtained over .20 years to study reproductive and migratory strategies of these species in southwestern Europe. Within the Iberian Peninsula, several different strategies regarding sex distribution and migratory behavior were observed within each o...

  11. Plasmid and chromosome segregation in prokaryotes

    DEFF Research Database (Denmark)

    Møller-Jensen, Jakob; Bugge Jensen, Rasmus; Gerdes, Kenn

    2000-01-01

    Recent major advances in the understanding of prokaryotic DNA segregation have been achieved by using fluorescence microscopy to visualize the localization of cellular components. Plasmids and bacterial chromosomes are partitioned in a highly dynamic fashion, suggesting the presence of a mitotic......-like apparatus in prokaryotes. The identification of chromosomal homologues of the well-characterized plasmid partitioning genes indicates that there could be a general mechanism of bacterial DNA partitioning. Udgivelsesdato: July 1...

  12. A Spatially Extended Model for Residential Segregation

    OpenAIRE

    Antonio Aguilera; Edgardo Ugalde

    2006-01-01

    We analyze urban spatial segregation phenomenon in terms of the income distribution over a population, and an inflationary parameter weighting the evolution of housing prices. For this, we develop a discrete spatially extended model based on a multiagent approach. In our model, the mobility of socioeconomic agents is driven only by the housing prices. Agents exchange location in order to fit their status to the cost of their ...

  13. Segregation effects in DEEP2 galaxy groups

    CERN Document Server

    Nascimento, Raquel S; Lopes, Paulo A A

    2016-01-01

    We investigate segregation phenomena in galaxy groups in the range of $0.20.6$) redshift groups. Assuming that the color index ${(U-B)_0}$ can be used as a proxy for the galaxy type, we found that the fraction of blue (star-forming) objects is higher in the high-z sample, with blue objects being dominant at $M_{B}>-19.5$ for both samples, and red objects being dominant at $M_{B}<-19.5$ only for the low-z sample. Also, the radial variation of the red fraction indicates that there are more red objects with $Rsegregation, at the 99%c.l., for the low-z sample: redder and brighter galaxies present lower velocity dispersions than bluer and fainter ones. We also find a weaker evidence for spatial segregation between red and blue objects, at the 70%c.l. The analysis of the high-z sample reveals a different result: red and blue galaxies have velocity dispersion distributions not statistically distinc...

  14. How population structure shapes neighborhood segregation.

    Science.gov (United States)

    Bruch, Elizabeth E

    2014-03-01

    This study provides a framework for understanding how population composition conditions the relationship between individuals' choices about group affiliation and aggregate patterns of social separation or integration. The substantive focus is the role of income inequality in racial residential segregation. The author identifies three population parameters--between-group inequality, within-group inequality, and relative group size--that determine how income inequality between race groups affects racial segregation. She uses data from the Panel Study of Income Dynamics to estimate models of individual-level residential mobility and incorporates these estimates into agent-based models. She then simulates segregation dynamics under alternative assumptions about (1) the relative size of minority groups and (2) the degree of correlation between race and income among individuals. The author finds that income inequality can have offsetting effects at the high and low ends of the income distribution. She demonstrates the empirical relevance of the simulation results using fixed-effects, metro-level regressions applied to 1980-2000 U.S. census data. PMID:25009360

  15. Implementing spatial segregation measures in R.

    Science.gov (United States)

    Hong, Seong-Yun; O'Sullivan, David; Sadahiro, Yukio

    2014-01-01

    Reliable and accurate estimation of residential segregation between population groups is important for understanding the extent of social cohesion and integration in our society. Although there have been considerable methodological advances in the measurement of segregation over the last several decades, the recently developed measures have not been widely used in the literature, in part due to their complex calculation. To address this problem, we have implemented several newly proposed segregation indices in R, an open source software environment for statistical computing and graphics, as a package called seg. Although there are already a few standalone applications and add-on packages that provide access to similar methods, our implementation has a number of advantages over the existing tools. First, our implementation is flexible in the sense that it provides detailed control over the calculation process with a wide range of input parameters. Most of the parameters have carefully chosen defaults, which perform acceptably in many situations, so less experienced users can also use the implemented functions without too much difficulty. Second, there is no need to export results to other software programs for further analysis. We provide coercion methods that enable the transformation of our output classes into general R classes, so the user can use thousands of standard and modern statistical techniques, which are already available in R, for the post-processing of the results. Third, our implementation does not require commercial software to operate, so it is accessible to a wider group of people. PMID:25415326

  16. A Spatially Extended Model for Residential Segregation

    Directory of Open Access Journals (Sweden)

    Antonio Aguilera

    2007-01-01

    Full Text Available We analyze urban spatial segregation phenomenon in terms of the income distribution over a population, and an inflationary parameter weighting the evolution of housing prices. For this, we develop a discrete spatially extended model based on a multiagent approach. In our model, the mobility of socioeconomic agents is driven only by the housing prices. Agents exchange location in order to fit their status to the cost of their housing. On the other hand, the price of a particular house depends on the status of its tenant, and on the neighborhood mean lodging cost weighted by a control parameter. The agent's dynamics converges to a spatially organized configuration, whose regularity is measured by using an entropy-like indicator. This simple model provides a dynamical process organizing the virtual city, in a way that the population inequality and the inflationary parameter determine the degree of residential segregation in the final stage of the process, in agreement with the segregation-inequality thesis put forward by Douglas Massey.

  17. Implementing spatial segregation measures in R.

    Directory of Open Access Journals (Sweden)

    Seong-Yun Hong

    Full Text Available Reliable and accurate estimation of residential segregation between population groups is important for understanding the extent of social cohesion and integration in our society. Although there have been considerable methodological advances in the measurement of segregation over the last several decades, the recently developed measures have not been widely used in the literature, in part due to their complex calculation. To address this problem, we have implemented several newly proposed segregation indices in R, an open source software environment for statistical computing and graphics, as a package called seg. Although there are already a few standalone applications and add-on packages that provide access to similar methods, our implementation has a number of advantages over the existing tools. First, our implementation is flexible in the sense that it provides detailed control over the calculation process with a wide range of input parameters. Most of the parameters have carefully chosen defaults, which perform acceptably in many situations, so less experienced users can also use the implemented functions without too much difficulty. Second, there is no need to export results to other software programs for further analysis. We provide coercion methods that enable the transformation of our output classes into general R classes, so the user can use thousands of standard and modern statistical techniques, which are already available in R, for the post-processing of the results. Third, our implementation does not require commercial software to operate, so it is accessible to a wider group of people.

  18. Integration and segregation in auditory scene analysis

    Science.gov (United States)

    Sussman, Elyse S.

    2005-03-01

    Assessment of the neural correlates of auditory scene analysis, using an index of sound change detection that does not require the listener to attend to the sounds [a component of event-related brain potentials called the mismatch negativity (MMN)], has previously demonstrated that segregation processes can occur without attention focused on the sounds and that within-stream contextual factors influence how sound elements are integrated and represented in auditory memory. The current study investigated the relationship between the segregation and integration processes when they were called upon to function together. The pattern of MMN results showed that the integration of sound elements within a sound stream occurred after the segregation of sounds into independent streams and, further, that the individual streams were subject to contextual effects. These results are consistent with a view of auditory processing that suggests that the auditory scene is rapidly organized into distinct streams and the integration of sequential elements to perceptual units takes place on the already formed streams. This would allow for the flexibility required to identify changing within-stream sound patterns, needed to appreciate music or comprehend speech..

  19. From Schelling to Schools: A Comparison of a Model of Residential Segregation with a Model of School Segregation

    OpenAIRE

    Victor Ionut Stoica; Andreas Flache

    2014-01-01

    We address theoretically whether and under what conditions Schelling’s celebrated result of ‘self-organized’ unintended residential segregation may also apply to school segregation. We propose here a computational model of school segregation that is aligned with a corresponding Schelling-type model of residential segregation. To adapt the model for application to school segregation, we move beyond previous work by combining two preference arguments in modeling parents’ school choice, ...

  20. Mutiscale Modeling of Segregation in Granular Flows

    Energy Technology Data Exchange (ETDEWEB)

    Jin Sun

    2007-08-03

    Modeling and simulation of segregation phenomena in granular flows are investigated. Computational models at different scales ranging from particle level (microscale) to continuum level (macroscale) are employed in order to determine the important microscale physics relevant to macroscale modeling. The capability of a multi-fluid model to capture segregation caused by density difference is demonstrated by simulating grain-chaff biomass flows in a laboratory-scale air column and in a combine harvester. The multi-fluid model treats gas and solid phases as interpenetrating continua in an Eulerian frame. This model is further improved by incorporating particle rotation using kinetic theory for rapid granular flow of slightly frictional spheres. A simplified model is implemented without changing the current kinetic theory framework by introducing an effective coefficient of restitution to account for additional energy dissipation due to frictional collisions. The accuracy of predicting segregation rate in a gas-fluidized bed is improved by the implementation. This result indicates that particle rotation is important microscopic physics to be incorporated into the hydrodynamic model. Segregation of a large particle in a dense granular bed of small particles under vertical. vibration is studied using molecular dynamics simulations. Wall friction is identified as a necessary condition for the segregation. Large-scale force networks bearing larger-than-average forces are found with the presence of wall friction. The role of force networks in assisting rising of the large particle is analyzed. Single-point force distribution and two-point spatial force correlation are computed. The results show the heterogeneity of forces and a short-range correlation. The short correlation length implies that even dense granular flows may admit local constitutive relations. A modified minimum spanning tree (MST) algorithm is developed to asymptotically recover the force statistics in the

  1. Coupling between bulk ordering and surface segregation: from alloy surfaces to surface alloys

    International Nuclear Information System (INIS)

    -The knowledge of the alloy surfaces is of prime interest to understand their catalytic properties. On the one hand, the determination of the stability of the surface alloys depends very strongly on the behaviours of the AcB1-c alloy surfaces. On the other hand, the knowledge of the kinetics of the formation-dissolution of surface alloys can allow to understand the equilibrium segregation isotherm. We have then studied the relation between the equilibrium surface segregation in an alloy AcB1-c and the kinetics of dissolution of a few metallic layers of A/B and the inverse deposit. We have used an energetic model derived from the electronic structure (T.I.B.M.) allowing us to study the surface segregation both in the disordered state and in the ordered one. The kinetics of dissolution were studied using the kinetic version of this model (K.T.I.B.M.) consistent with the equilibrium model. To illustrate our study, we have chosen the Cu-Pd system, a model for the formation of surface alloys and for which a great number of studies, both experimental and theoretical, are in progress. We then have shown for the (111) surface of this system that the surface alloys obtained during the dissolution are related to the alloy surfaces observed for the equilibrium segregation. The Cu-Pd system is characteristic of systems which have a weak segregation energy. Then, we have performed an equivalent study for a system with a strong segregation energy. Our choice was directly put on the Pt-Sn system. The surface behaviour, both in equilibrium and during the kinetics of dissolution, is very different from the Cu-Pd case. In particular, we have found pure 2-D surface alloys. Finally, a quenched molecular dynamics study has allowed us to determine the relative stability of various possible surface superstructures. (author)

  2. Evaluation of the Heat, Entropy, and Rotational Changes Produced by Gravitational Segregation during Core Formation

    Institute of Scientific and Technical Information of China (English)

    Anne M. Hofmeister; Robert E. Criss

    2015-01-01

    Core formation by gravitational segregation allegedly released sufficient interior heat to melt the Earth. Analysis of the energetics, which compare gravitational potential energy (Ug) of a fictitious, homogeneous reference state to Earth’s current layered configuration, needs updating to correct errors and omissions, and to accommodate recent findings: (1) An erroneous positive sign was used for Ug while maintaining the reference value of 0 at infinity, which results in an incorrect sign for ΔUg, which is crucial in determining whether a process is endothermic or exothermic. (2) The value of Ug for Earth’s initial state is uncertain. (3) Recent meteorite evidence indicates that core formation began before the Earth was full-sized, which severely limitsDUg. (4) Inhomogeneous accretion additionally reducedDUg. (5) The potentially large effect of differential rotation between the core and the mantle was not accounted for. (6) Entropy changes associated with creating order were neglected. Accordingly, we revise values of Ug, evaluate uncertainties, and show thatDUg was converted substantially to configurational energy (TDS). These considerations limit the large sources of primordial heat to impacts and radioactivity. Although these processes may play a role in core formation, their energies are independent of gravitational segregation, which produces order and rotational energy, not internal heat. Instead, gravitational segregation promotes planetary cooling mainly because it segregates lithophilic radioactive elements upward, increasing surface heat flux while shortening the distance over which radiogenic heat diffuses outwards.

  3. Axial segregation of granular media rotated in a drum mixer: Pattern evolution

    International Nuclear Information System (INIS)

    In the traditional axial segregation effect, a homogeneous mixture of different types of granular material rotated in a drum mixer segregates into surface bands of relatively pure single concentrations along the axis of rotation. This effect primarily has been studied with respect to the initial segregation. However, the initial pattern is not stable, but evolves in time with continued rotation through metastable states of fewer and fewer bands. We describe two experimental studies of this evolution that provide a more complete picture of the dynamics involved in the pattern progression. The use of a charge coupled device camera in conjunction with digital analysis techniques provides a quantitative measure of the state of the surface as a function of time, while magnetic resonance imaging techniques provide a noninvasive method for studying the segregation beneath the surface. These methods indicate that the underlying mechanisms for the pattern evolution may originate in the bulk of the material, beneath the avalanching surface. copyright 1997 The American Physical Society

  4. Vapor segregation and loss in basaltic melts

    Science.gov (United States)

    Edmonds, M.; Gerlach, T.M.

    2007-01-01

    Measurements of volcanic gases at Pu'u'O??'o??, Kilauea Volcano, Hawai'i, reveal distinct degassing regimes with respect to vapor segregation and loss during effusive activity in 2004-2005. Three styles of vapor loss are distinguished by the chemical character of the emitted volcanic gases, measured by open path Fourier transform infrared spectroscopy: 1 persistent continuous gas emission, 2 gas piston events, and 3 lava spattering. Persistent continuous gas emission is associated with magma ascent and degassing beneath the crater vents, then eruption of the degassed magma from flank vents. Gas piston events are the result of static gas accumulation at depths of 400-900 m beneath Pu'u'O??'o??. A CO2-rich gas slug travels up the conduit at a few meters per second, displacing magma as it expands. Lava spattering occurs due to dynamic bubble coalescence in a column of relatively stagnant magma. The Large gas bubbles are H2O rich and are generated by open-system degassing at depths of segregation in basaltic melts, but their implications differ. Accumulation and segregation of CO2-rich vapor at depth does not deplete the melt of H2O (required to drive lava fountains near to the surface) and therefore gas piston events can occur interspersed with lava fountaining activity. Lava spattering, however, efficiently strips H2O-rich vapor from magma beneath the crater vents; the magma must then erupt effusively from vents on the flank of the cone. ?? 2007 The Geological Society of America.

  5. Surface segregation in HAYNES 230 alloy

    International Nuclear Information System (INIS)

    The surface segregation in the Ni-based alloy HAYNES 230 was studied by Auger Electron Spectroscopy and X-ray Photoelectron Spectroscopy between 400 and 1100 deg. C. The qualitative variations of the surface contents of S, P, W, Mo, N, Si, and Mn were determined as a function of annealing temperature and time. It was found that at 925 deg. C the maximum coverage of sulphur at the alloy surface is in the range 0.06-0.15 monolayers. Chromium evaporation from the HAYNES 230 surface under UHV conditions is clearly evidenced for annealing at 1100 deg. C

  6. Surface segregation in HAYNES 230 alloy

    Science.gov (United States)

    Pop, D.; Wolski, K.

    2006-12-01

    The surface segregation in the Ni-based alloy HAYNES 230 was studied by Auger Electron Spectroscopy and X-ray Photoelectron Spectroscopy between 400 and 1100 °C. The qualitative variations of the surface contents of S, P, W, Mo, N, Si, and Mn were determined as a function of annealing temperature and time. It was found that at 925 °C the maximum coverage of sulphur at the alloy surface is in the range 0.06-0.15 monolayers. Chromium evaporation from the HAYNES 230 surface under UHV conditions is clearly evidenced for annealing at 1100 °C.

  7. Potential donor segregation to promote blood donation.

    Science.gov (United States)

    Martín-Santana, Josefa D; Beerli-Palacio, Asunción

    2008-04-01

    This work is set in the field of social marketing and more specifically in the context of blood donation. Its principal objective focuses on segregating potential donors by using the inhibitors or barriers to a blood donation behaviour as criteria. Moreover, an analysis of the predisposition to donate blood, the intrinsic and extrinsic motivations for donating blood, and the incentives that may stimulate their donation conduct was conducted for each of the four identified groups. The results reveal that the four segments differ significantly in their predisposition to donate, in their motivations and in the incentives that encourage them to donate blood. PMID:18343199

  8. Segregation and sporadic cases in families with Hunter's syndrome.

    OpenAIRE

    Machill, G; Barbujani, G.; Danieli, G A; Herrmann, F H

    1991-01-01

    Segregation analysis on five samples of families with Hunter's syndrome (158 cases overall) shows that the mutant allele segregates in agreement with Mendelian expectations for an X linked recessive disease, but the proportion of sporadic cases is significantly lower than expected under mutation-selection equilibrium. Heterogeneity among the samples is apparent, but it is caused entirely by a sample of Ashkenazi families, whose segregation pattern has previously been interpreted as supporting...

  9. Occupational Sex Segregation and Working Time: Regional Evidence from Germany

    OpenAIRE

    Humpert Stephan

    2014-01-01

    This paper provides descriptive evidence for declining occupational sex segregation on the German labor market, especially concerning the regional differences between the former East and West Germany. I use segregation measures and long-run social security data for the decade of 1992 to 2004. While segregation has declined over time, it remains higher for the eastern part of Germany. Although this finding is observable for full-time and part-time work, segr...

  10. Metropolitan Racial Residential Segregation and Cardiovascular Mortality: Exploring Pathways

    OpenAIRE

    Greer, Sophia; Kramer, Michael R; Cook-Smith, Jessica N.; Casper, Michele L.

    2013-01-01

    Racial residential segregation has been associated with an increased risk for heart disease and stroke deaths. However, there has been little research into the role that candidate mediating pathways may play in the relationship between segregation and heart disease or stroke deaths. In this study, we examined the relationship between metropolitan statistical area (MSA)-level segregation and heart disease and stroke mortality rates, by age and race, and also estimated the effects of various ed...

  11. Gender essentialism and occupational segregation in insolvency practice

    OpenAIRE

    Joyce, Yvonne; Walker, Stephen P.

    2015-01-01

    Advances towards egalitarianism in professional recruitment may be offset by processes of occupational re-segregation. Drawing on gender theory this paper investigates horizontal segregation in the UK insolvency profession, as revealed through the lived experiences of female and male practitioners. It is shown that horizontal segregation pervades at different levels of practice and is undergirded by various elements of gender essentialism. Physical essentialism explains why insolvency practic...

  12. The impact of fiscal decentralization on income segregation

    OpenAIRE

    Francisco Martínez Mora

    2004-01-01

    We investigate how decentralizing the provision and funding of a publicly provided good from central (or regional) to local governments affects income segregation in an urban area. As the previous theoretical literature suggests, local provision and funding of a publicly provided good by itself generates incentives for income segregation. However, other segregating forces such as local amenities are also at work in urban areas. We show that, once this important feature of urban economies is c...

  13. 49 CFR 174.81 - Segregation of hazardous materials.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Segregation of hazardous materials. 174.81 Section... General Handling and Loading Requirements § 174.81 Segregation of hazardous materials. (a) This section... section: Segregation Table for Hazardous Materials Class or Division Notes 1.1, 1.2 1.3 1.4 1.5 1.6 2.1...

  14. Housing Tenure and Residential Segregation in Metropolitan America

    OpenAIRE

    Friedman, Samantha; Tsao, Hui-shien; Chen, Cheng

    2013-01-01

    Homeownership, a symbol of the American dream, is one of the primary ways through which families accumulate wealth, particularly for blacks and Hispanics. Surprisingly, no study has explicitly documented the segregation of minority owners and renters from whites. Using data from Census 2000, this study aims to fill this gap. Analyses here reveal that the segregation of black renters relative to whites is significantly lower than the segregation of black owners from whites, controlling for rel...

  15. Racial/ethnic residential segregation and cardiovascular disease risk

    OpenAIRE

    Kershaw, Kiarri N.; Albrecht, Sandra S.

    2015-01-01

    A growing body of research has examined whether racial/ethnic residential segregation contributes to health disparities, but recent findings in the literature, particularly with respect to cardiovascular disease (CVD) risk, have not been summarized. This review provides an overview of findings from studies of racial/ethnic residential segregation of non-Hispanic blacks and Hispanics with CVD risk published between January 2011 and July 2014. The majority of studies of black segregation showed...

  16. Residential Segregation and Immigrants' Satisfaction with the Neighborhood in Germany

    OpenAIRE

    Dill, Verena; Jirjahn, Uwe; Tsertsvadze, Georgi

    2011-01-01

    Using data from the German Socio-Economic Panel, this study examines the relationship between immigrant residential segregation and immigrants' satisfaction with the neighborhood. The estimates show that immigrants living in segregated areas are less satisfied with the neighborhood. This is consistent with the hypothesis that housing discrimination rather than self-selection plays an important role in immigrant residential segregation. Our result holds true even when controlling for other inf...

  17. Segregation or Integration? Immigrant Self-Employment in Switzerland

    OpenAIRE

    Juhasz Liebermann, Anne; Suter, Christian; Iglesias, Katia

    2016-01-01

    This article investigates whether immigrant self-employment is related more to segregation in the labour market than work as an employee (making it justifiable to speak of ethnic business) or whether, on the contrary, it reflects equality with the self-employment by the Swiss. The distinctive features of this research design are the comparison of ethnic segregation in the labour market with gender-specific segregation and the fact that, apart from migrants of the first generation, members of ...

  18. Factors Influencing Occupational Segregation by Gender in Malaysia

    OpenAIRE

    Noor Rahamah Abu Bakar

    2014-01-01

    In many developing countries, occupational segregation by gender is a topic that is much discussed but very few researches had been carried out. In Malaysia, secondary sources of data, such as the Population and Housing Census reports and Social Statistics Bulletins of the Malaysian Statistics Department do show that there have been some changes in the general trends of occupational segregation in the country but factual details of occupational segregation based on gender are rather scanty. T...

  19. Evaluating segregation in HSLA steels using computational thermodynamics

    OpenAIRE

    Meire Guimarães Lage; André Luiz Vasconcellos da Costa e Silva

    2015-01-01

    A low level of segregation in high strength steel plates used to manufacture large diameter pipes is important for the performance of these materials in sour environments. In this work, the level of segregation of different HSLA steels was assessed by computational thermodynamics to identify the most promising compositions. Equilibrium phase diagrams and mass fraction of solid phase diagrams were used to quantify the segregation at the end of solidification. It was verified from the results t...

  20. Mapping School Segregation: Using GIS to Explore Racial Segregation between Schools and Their Corresponding Attendance Areas

    Science.gov (United States)

    Sohoni, Deenesh; Saporito, Salvatore

    2009-01-01

    We examine whether student enrollment in nonneighborhood schools changes levels of racial segregation in public schools across urban school districts by comparing the racial composition of schools and their corresponding attendance area. This comparison was made possible by using geographic information systems (GIS) to link maps of elementary,…

  1. Causes of Educational Segregation in Sweden--School Choice or Residential Segregation

    Science.gov (United States)

    Yang Hansen, Kajsa; Gustafsson, Jan-Eric

    2016-01-01

    The aims of the study were to examine changes in school segregation across different types of municipalities between 1998 and 2011 in Sweden, and to explore the extent to which these changes are the consequences of school choice. Multilevel models were applied to register data using a counterfactual approach. The results showed that school…

  2. First-Principles Study of Mo Segregation in MoNi(111: Effects of Chemisorbed Atomic Oxygen

    Directory of Open Access Journals (Sweden)

    Yanlin Yu

    2015-12-01

    Full Text Available Segregation at metal alloy surfaces is an important issue because many electrochemical and catalytic properties are directly correlated to the surface composition. We have performed density functional theory calculations for Mo segregation in MoNi(111 in the presence of chemisorbed atomic oxygen. In particular, the coverage dependence and possible adsorption-induced segregation phenomena are addressed by investigating segregation energies of the Mo atom in MoNi(111. The theoretical calculated results show that the Mo atom prefers to be embedded in the bulk for the clean MoNi(111, while it segregates to the top-most layer when the oxygen coverage is thicker than 1/9 monolayer (ML. Furthermore, we analyze the densities of states for the clean and oxygen-chemisorbed MoNi(111, and see a strong covalent bonding between Mo d-band states and O p-states. The present study provides valuable insight for exploring practical applications of Ni-based alloys as hydrogen evolution electrodes.

  3. Occupational sex segregation and working time: Regional evidence from Germany

    Directory of Open Access Journals (Sweden)

    Humpert Stephan

    2014-01-01

    Full Text Available This paper provides descriptive evidence for declining occupational sex segregation on the German labor market, especially concerning the regional differences between the former East and West Germany. I use segregation measures and long-run social security data for the decade of 1992 to 2004. While segregation has declined over time, it remains higher for the eastern part of Germany. Although this finding is observable for full-time and part-time work, segregation is always lower in part-time employment.

  4. Chloroplast genetics of chlamydomonas. I. Allelic segregation ratios

    International Nuclear Information System (INIS)

    This paper presents allelic segregation data from a series of 16 crosses segregated for nuclear and chloroplast genes. By means of pedigree analysis, segregants of chloroplast genes. By means of pedigree analysis, segregants of chloroplast markers occurring in the zygote have been distinguished from those occurring in zoospore clones. The genes ac1, ac2, and tm1 showed little if any deviation from 1:1 either in zygotic segregation or in zoospore clones. The genes sm2, ery, and spc showed a significant excess of the allele from the mt+ parent in zygotes. However, in zoospores, mt+ excess was seen only when the allele was the mutant (resistant) form but not when it was wild type (sensitive). These results show that the extent of preferential segregation differs in zygotes and in zoospores, and that preferential segregation is influenced by map location and by allele specificity. A comparison of progeny from zygotes mated after 0, 15'', 30'', and 50'' uv irradiation of the mt+ gametes demonstrated the lack of an effect of uv upon allelic segregation ratios. In total, these results exclude the multi-copy model of chloroplast genome segregation suggested by Gillham. Boynton and Lee (1974) and support the diploid model we have previously proposed

  5. Chloroplast genetics of chlamydomonas. I. Allelic segregation ratios. [UV radiation

    Energy Technology Data Exchange (ETDEWEB)

    Sager, R.; Ramanis, Z.

    1976-06-01

    This paper presents allelic segregation data from a series of 16 crosses segregated for nuclear and chloroplast genes. By means of pedigree analysis, segregants of chloroplast genes. By means of pedigree analysis, segregants of chloroplast markers occurring in the zygote have been distinguished from those occurring in zoospore clones. The genes ac1, ac2, and tm1 showed little if any deviation from 1:1 either in zygotic segregation or in zoospore clones. The genes sm2, ery, and spc showed a significant excess of the allele from the mt+ parent in zygotes. However, in zoospores, mt+ excess was seen only when the allele was the mutant (resistant) form but not when it was wild type (sensitive). These results show that the extent of preferential segregation differs in zygotes and in zoospores, and that preferential segregation is influenced by map location and by allele specificity. A comparison of progeny from zygotes mated after 0, 15'', 30'', and 50'' uv irradiation of the mt+ gametes demonstrated the lack of an effect of uv upon allelic segregation ratios. In total, these results exclude the multi-copy model of chloroplast genome segregation suggested by Gillham. Boynton and Lee (1974) and support the diploid model we have previously proposed.

  6. Grain boundary segregation and intergranular fracture in molybdenum

    International Nuclear Information System (INIS)

    The present paper reports results from a systematic study of segregation and intergranular embrittlement in binary molybdenum-oxygen and ternary molybdenum-oxygen-carbon alloys. The experiments were carried out on 'bamboo' specimens containing a series of identical single grain boundaries traversing their cross-sections. Measurements have been made of the activation energy for oxygen segregation to grain boundaries in the binary alloys. The influence of carbon additions on the level of oxygen segregation and the influence of oxygen segregation on the energy to fracture have been studied. Results from metallographic studies show the effects of segregation on fracture surface topography and dislocation surfaces immediately adjacent to the fracture surfaces. The thermodynamics of oxygen segregation to grain boundaries is considered and the role played by carbon in inhibiting segregation. The influence of segregation on the work of fracture is also considered and it is shown that the reduction in oxygen segregation resulting from the addition of carbon produces small increases in fracture energy. This increases the local stress to propagate a crack sufficiently to promote plastic deformation which blunts the crack tip; this reduces the stress concentration at the crack tip and the applied fracture stress and the work to fracture is thus increased. (author)

  7. Economic Residential Segregation and Educational Achievements: Evidence from Chile

    OpenAIRE

    Román, Miguel Vargas

    2012-01-01

    Using a database from Chile, we have tested empirically the effects of economic residential segregation on educational achievements. Our hypothesis is based on literature’s findings about segregation’s negative impact on individuals’ well being. We found that segregation has negative impacts. This result would have interesting policy implications and goes in the opposite directions of those investigations’ findings, which indicate that segregation has just negligible effects. Keywords...

  8. Wilhelm Weinberg's early contribution to segregation analysis.

    Science.gov (United States)

    Stark, Alan; Seneta, Eugene

    2013-09-01

    Wilhelm Weinberg (1862-1937) is a largely forgotten pioneer of human and medical genetics. His name is linked with that of the English mathematician G. H. Hardy in the Hardy-Weinberg law, pervasive in textbooks on population genetics since it expresses stability over generations of zygote frequencies AA, Aa, aa under random mating. One of Weinberg's signal contributions, in an article whose centenary we celebrate, was to verify that Mendel's segregation law still held in the setting of human heredity, contrary to the then-prevailing view of William Bateson (1861-1926), the leading Mendelian geneticist of the time. Specifically, Weinberg verified that the proportion of recessive offspring genotypes aa in human parental crossings Aa × Aa (that is, the segregation ratio for such a setting) was indeed p=1/4. We focus in a nontechnical way on his procedure, called the simple sib method, and on the heated controversy with Felix Bernstein (1878-1956) in the 1920s and 1930s over work stimulated by Weinberg's article. PMID:24018765

  9. SOCIAL POLARIZATION AND SEGREGATION IN BEIJING

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The biggest change in Beijing during the last decade has been in its social structure. This transition is changing the existing situation of social "equality", and leads to polarization both in individual communities and in society as a whole. As a result, social variations and conflicting interest are growing, and some new social groups are emerging. In this paper we seek to explore a new urban phenomenon in post-1984 Beijing: social polarization and segregation. At first, we will discuss some elements explaining social polarization. The elements and the processes can be traced back to two main aspects of the economic reforms, namely the internal reforms unleashing a huge rural exodus and the open door policy. Special attention will be paid to the new lower end of the social ladder, which is made up largely by rural migrantsthat make up the so-called floating population.Finally we will explore how these social changes translate into urban segregation, with some consideration for future develop-ments.

  10. Decentralization as a Cause of Spatial Segregation

    Directory of Open Access Journals (Sweden)

    Jasarovic Ema Alihodzic

    2016-01-01

    Full Text Available City represents an incomplete dynamic process prone to the expansion with a causal link between urban expansion and socio-spatial segregation. The socio-spatial distribution in the city is mostly related to the increased social polarization and inequality. There is a clear connection between divided society and divided city: if society is divided, urban space must be divided. It is the question of the relations between the social inequalities on one hand, and spatial segregation on the other. In the last 10 years, Podgorica is the city that shows alarming statistic values when it comes to demographic trends and the influx of the residents from the northern municipalities, which necessarily causes the city sprawl. Past experiences show that city is unevenly expanding, creating new functions and zones expressed by socio-spatial differences. The beginning of this process lies in modernist conception of the city, by which city was mostly developed, while the current functional organization is based on the same concept. With the first urban plans, which carried similarproblems mentioned in previous section, Podgorica was divided into three clearly differentiated zones: Stara Varoš, Nova Varoš and Novi grad, which became a platform for hierarchical divisions within the space, reflecting them in the society.

  11. Coarsening of self-organised clusters due to segregation in a two-component granular monolayer

    Science.gov (United States)

    Reis, Pedro Miguel; Mullin, Tom

    2001-11-01

    We present results of an experimental investigation of a horizontally vibrated quasi-2-dimensional granular mixture in which particles are mainly driven by frictional forces with the container. A new mode of particle segregation is found in which striped clusters of the larger particles spontaneously emerge out of an initially homogeneous mixture. The system exhibits a critical concentration ratio, reminiscent of a phase transition, below which segregation is suppressed. The striped structures coarsen with time and the average strip width obeys a t^1/4 powerlaw. These domains can also exhibit collective nonlinear behaviour. Both singly and doubly periodic states as well as chaotic phenomena have been found. Such dynamical states appear to be dependent on the granular temperature.

  12. Algorithms for physical segregation of coal

    Science.gov (United States)

    Ganguli, Rajive

    The capability for on-line measurement of the quality characteristics of conveyed coal now enables mine operators to take advantage of the inherent heterogeneity of those streams and split them into wash and no-wash stocks. Relative to processing the entire stream, this reduces the amount of coal that must be washed at the mine and thereby reduces processing costs, recovery losses, and refuse generation levels. In this dissertation, two classes of segregation algorithms, using time series models and moving windows are developed and demonstrated using field and simulated data. In all of the developed segregation algorithms, a "cut-off" ash value was computed for coal scanned on the running conveyor belt by the ash analyzer. It determined if the coal was sent to the wash pile or to the nowash pile. Forecasts from time series models, at various lead times ahead, were used in one class of the developed algorithms, to determine the cut-off ash levels. The time series models were updated from time to time to reflect changes in process. Statistical Process Control (SPC) techniques were used to determine if an update was necessary at a given time. When an update was deemed necessary, optimization techniques were used to determine the next best set of model parameters. In the other class of segregation algorithms, "few" of the immediate past observations were used to determine the cut-off ash value. These "few" observations were called the window width . The window width was kept constant in some variants of this class of algorithms. The other variants of this class were an improvement over the fixed window width algorithms. Here, the window widths were varied rather than kept constant. In these cases, SPC was used to determine the window width at any instant. Statistics of the empirical distribution and the normal distribution were used in computation of the cut-off ash value in all the variants of this class of algorithms. The good performance of the developed algorithms

  13. On the Origin of Mass Segregation in NGC 3603

    Science.gov (United States)

    Pang, Xiaoying; Grebel, Eva K.; Allison, Richard J.; Goodwin, Simon P.; Altmann, Martin; Harbeck, Daniel; Moffat, Anthony F. J.; Drissen, Laurent

    2013-02-01

    We present deep Hubble Space Telescope/Wide Field and Planetary Camera 2 photometry of the young HD 97950 star cluster in the giant H II region NGC 3603. The data were obtained in 1997 and 2007 permitting us to derive membership based on proper motions of the stars. Our data are consistent with an age of 1 Myr for the HD 97950 cluster. A possible age spread, if present in the cluster, appears to be small. The global slope of the incompleteness-corrected mass function for member stars within 60'' is Γ = -0.88 ± 0.15, which is flatter than the value of a Salpeter slope of -1.35. The radially varying mass function shows pronounced mass segregation ranging from slopes of -0.26 ± 0.32 in the inner 5'' to -0.94 ± 0.36 in the outermost annulus (40''-60''). Stars more massive than 50 M ⊙ are found only in the cluster center. The Λ minimum spanning tree technique confirms significant mass segregation down to 30 M ⊙. The dependence of Λ on mass, i.e., that high-mass stars are more segregated than low-mass stars, and the (weak) dependence of the velocity dispersion on stellar mass might imply that the mass segregation is dynamical in origin. While primordial segregation cannot be excluded, the properties of the mass segregation indicate that dynamical mass segregation may have been the dominant process for segregation of high-mass stars.

  14. Quantitative trait locus mapping can benefit from segregation distortion.

    Science.gov (United States)

    Xu, Shizhong

    2008-12-01

    Segregation distortion is a phenomenon that has been observed in many experimental systems. How segregation distortion among markers arises and its impact on mapping studies are the focus of this work. Segregation distortion of markers can be considered to arise from segregation distortion loci (SDL). I develop a theory of segregation distortion and show that the presence of only a few SDL can cause the entire chromosome to distort from Mendelian segregation. Segregation distortion is detrimental to the power of detecting quantitative trait loci (QTL) with dominance effects, but it is not always a detriment to QTL mapping for additive effects. When segregation distortion of a locus is a random event, the SDL is beneficial to QTL mapping approximately 44% of the time. If SDL are present and ignored, power loss can be substantial. A dense marker map can be used to ameliorate the situation, and if dense marker information is incorporated, power loss is minimal. However, other situations are less benign. A method that can simultaneously map QTL and SDL is discussed, maximizing both use of mapping resources and use by agricultural and evolutionary biologists. PMID:18957707

  15. Coleman Revisited: School Segregation, Peers, and Frog Ponds

    Science.gov (United States)

    Goldsmith, Pat Rubio

    2011-01-01

    Students from minority segregated schools tend to achieve and attain less than similar students from White segregated schools. This study examines whether peer effects can explain this relationship using normative models and frog-pond models. Normative models (where peers become alike) suggest that minority schoolmates are a liability. Frog-pond…

  16. 46 CFR 111.60-9 - Segregation of vital circuits.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Segregation of vital circuits. 111.60-9 Section 111.60-9 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Wiring Materials and Methods § 111.60-9 Segregation of vital circuits. (a) General....

  17. 7 CFR 58.332 - Segregation of raw material.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Segregation of raw material. 58.332 Section 58.332 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... Procedures § 58.332 Segregation of raw material. The milk and cream received at the dairy plant shall...

  18. Deconstructing Systems of Segregation: Leadership Challenges in an Urban School

    Science.gov (United States)

    DeMatthews, David

    2014-01-01

    Special education policies can create structures of segregation and inequality. School leaders are often tasked with dismantling these structures while meeting expectations related to accountability policies. This case study involves a new principal at an urban school in a district with a long history of segregation reassigned to work at one of…

  19. 7 CFR 3015.10 - Physical segregation and eligibility.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 15 2010-01-01 2010-01-01 false Physical segregation and eligibility. 3015.10 Section 3015.10 Agriculture Regulations of the Department of Agriculture (Continued) OFFICE OF THE CHIEF....10 Physical segregation and eligibility. Except as provided in § 3015.11, awarding agencies shall...

  20. 27 CFR 24.191 - Segregation of operations.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Segregation of operations. 24.191 Section 24.191 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS WINE Production of Effervescent Wine § 24.191 Segregation of...

  1. Pre-Hire Factors and Workplace Ethnic Segregation (discussion paper)

    NARCIS (Netherlands)

    Stromgren, M.; Tammaru, T.; Van Ham, M.; Marcinzak, S.; Stjernstrom, O.; Lindgren, U.

    2011-01-01

    In addition to neighbourhoods of residence, family and places of work play important roles in producing and reproducing ethnic segregation. Therefore, recent research on ethnic segregation and contact is increasingly turning its attention from residential areas towards other important domains of dai

  2. Measuring Residential Segregation: An Application of Trend Surface Analysis.

    Science.gov (United States)

    Spriggs, William

    1984-01-01

    Presents a measure of racial residential segregation which conforms to the traditional attributes of segregation indices, but includes sensitivity to the spatial patterns of White and non-White residence in a city. Reviews earlier measures, describes the new one, and applies it to racial housing patterns in Norfolk, Virginia, in 1890. (KH)

  3. Patterns of Interethnic Residential Segregation in the Urban Southwest.

    Science.gov (United States)

    Lopez, Manual Mariano

    1981-01-01

    Compares patterns of residential segregation among Mexican Americans, Blacks, and Anglos for 1960 and 1970 and finds that, in spite of a striking similarity in the overall pattern, there have been some important changes. Further, city characteristics found to be good predictors of segregation for 1960 fail to adequately account for the same types…

  4. Campland: Racial Segregation of Roma in Italy. Country Reports Series.

    Science.gov (United States)

    Cahn, Claude; Carlisle, Kathryn D.; Fregoli, Claudia; Kiuranov, Deyan; Petrova, Dimitrina

    This report addresses racial segregation and human rights abuses against Roma in Italy, focusing on: "Anti-Gypsyism in Italy"; "Roma in Italy: Racial Segregation"; "Abuses by Police and Judicial Authorities" (e.g., abusive raids and evictions, abusive use of firearms, torture and physical abuse, discriminatory targeting of Roma by police, theft by…

  5. Using the minimum spanning tree to trace mass segregation

    CERN Document Server

    Allison, Richard J; Parker, Richard J; Zwart, Simon F Portegies; de Grijs, Richard; Kouwenhoven, M B N

    2009-01-01

    We present a new method to detect and quantify mass segregation in star clusters. It compares the minimum spanning tree (MST) of massive stars with that of random stars. If mass segregation is present, the MST length of the most massive stars will be shorter than that of random stars. This difference can be quantified (with an associated significance) to measure the degree of mass segregation. We test the method on simulated clusters in both 2D and 3D and show that the method works as expected. We apply the method to the Orion Nebula Cluster (ONC) and show that the method is able to detect the mass segregation in the Trapezium with a `mass segregation ratio' \\Lambda_{MSR}=8.0 \\pm 3.5 (where \\Lambda_{MSR}=1 is no mass segregation) down to 16 \\Msun, and also that the ONC is mass segregated at a lower level (~2.0 \\pm 0.5) down to 5 \\Msun. Below 5 \\Msun we find no evidence for any further mass segregation in the ONC.

  6. Predicting violence within genocide: a model of elite competition and ethnic segregation from Rwanda

    OpenAIRE

    McDoom, Omar

    2014-01-01

    Can we predict when and where violence will likely break out within cases of genocide? I present a theoretical model to help identify areas susceptible and resistant to violence during genocide. The model conceptualizes violence onset as a function of elite competition for control of the state from above and the ethnic segregation of society from below. First, in areas where extremist elite control is weak, violence is delayed or averted because a contest for control between pro-violence elit...

  7. School Quality and the Education-Health Relationship: Evidence from Blacks in Segregated Schools*

    OpenAIRE

    Frisvold, David; Golberstein, Ezra

    2011-01-01

    In this paper, we estimate the effect of school quality on the relationship between schooling and health outcomes using the substantial improvements in the quality of schools attended by black students in the segregated southern states during the mid-1900s as a source of identifying variation. Using data from the National Health Interview Survey, our results suggest that improvements in school quality, measured as the pupil-teacher ratio, average teachers’ wage, and length of the school year,...

  8. Heider balance, asymmetric ties, and gender segregation

    Science.gov (United States)

    Krawczyk, Małgorzata J.; del Castillo-Mussot, Marcelo; Hernández-Ramírez, Eric; Naumis, Gerardo G.; Kułakowski, Krzysztof

    2015-12-01

    To remove a cognitive dissonance in interpersonal relations, people tend to divide their acquaintances into friendly and hostile parts, both groups internally friendly and mutually hostile. This process is modeled as an evolution toward the Heider balance. A set of differential equations have been proposed and validated (Kułakowski et al., 2005) to model the Heider dynamics of this social and psychological process. Here we generalize the model by including the initial asymmetry of the interpersonal relations and the direct reciprocity effect which removes this asymmetry. Our model is applied to the data on enmity and friendship in 37 school classes and 4 groups of teachers in México. For each class, a stable balanced partition is obtained into two groups. The gender structure of the groups reveals stronger gender segregation in younger classes, i.e. of age below 12 years, a fact consistent with other general empirical results.

  9. Heider balance, asymmetric ties, and gender segregation

    CERN Document Server

    Krawczyk, Małgorzata J; Hernández-Ramirez, Eric; Naumis, Gerardo G; Kułakowski, Krzysztof

    2015-01-01

    To remove a cognitive dissonance in interpersonal relations, people tend to divide our acquaintances into friendly and hostile parts, both groups internally friendly and mutually hostile. This process is modeled as an evolution towards the Heider balance. A set of differential equations have been proposed and validated (Kulakowski {\\it et al}, IJMPC 16 (2005) 707) to model the Heider dynamics of this social and psychological process. Here we generalize the model by including the initial asymmetry of the interprersonal relations and the direct reciprocity effect which removes this asymmetry. Our model is applied to the data on enmity and friendship in 37 school classes and 4 groups of teachers in M\\'exico. For each class, a stable balanced partition is obtained into two groups. The gender structure of the groups reveals stronger gender segregation in younger classes, i.e. of age below 12 years, a fact consistent with other general empirical results.

  10. Dynamics of chromosome segregation in Escherichia coli

    DEFF Research Database (Denmark)

    Nielsen, Henrik Jørck

    2007-01-01

    Since the 1960’es the conformation and segregation of the chromosome in Escherichia coli has been a subject of interest for many scientists. However, after 40 years of research, we still know incredibly little about how the chromosome is organized inside the cell, how it manages to duplicate this...... and reliable method enabled us to start the analysis on the distribution of various chromosomal loci inside slowly growing cells. With the actual counting and measuring no longer being any problem we could easily analyze 14 loci distributed on the E.coli chromosome. More than 15.000 cells were...... on the P1 par system. Using the new system, which is based on the pMT1 par system from Yersenia pestis, we labeled loci on opposite sides of the E.coli chromosome simultaneously and were able to show that the E.coli chromosome is organized with one chromosomal arm in each cell half. This astounding...

  11. Uncovering Mass Segregation with Galaxy Analogues in Dark Matter Simulations

    CERN Document Server

    Joshi, Gandhali D; Wadsley, James

    2016-01-01

    We investigate mass segregation in group and cluster environments by identifying galaxy analogues in high-resolution dark matter simulations. Subhalos identified by the AHF and ROCKSTAR halo finders have similar mass functions, independent of resolution, but different radial distributions due to significantly different subhalo hierarchies. We propose a simple way to classify subhalos as galaxy analogues. The radial distributions of galaxy analogues agree well at large halo-centric radii for both AHF and ROCKSTAR but disagree near parent halo centres where the phase-space information used by ROCKSTAR is essential. We see clear mass segregation at small radii (within $0.5\\,r_{vir}$) with average galaxy analogue mass decreasing with radius. Beyond the virial radius, we find a mild trend where the average galaxy analogue mass increases with radius. These mass segregation trends are strongest in small groups and dominated by the segregation of low mass analogues. The lack of mass segregation in massive galaxy anal...

  12. Experimental determination of the segregation process using computer tomography

    Directory of Open Access Journals (Sweden)

    Konstantin Beckmann

    2016-07-01

    Full Text Available Modelling methods such as DEM and CFD are increasingly used for developing high efficient combine cleaning systems. For this purpose it is necessary to verify the complex segregation and separation processes in the combine cleaning system. One way is to determine the segregation and separation function using 3D computer tomography (CT. This method makes it possible to visualize and analyse the movement behaviour of the components of the mixture during the segregation and separation process as well as the derivation of descriptive process parameters. A mechanically excited miniature test rig was designed and built at the company CLAAS Selbstfahrende Erntemaschinen GmbH to achieve this aim. The investigations were carried out at the Fraunhofer Institute for Integrated Circuits IIS. Through the evaluation of the recorded images the segregation process is described visually. A more detailed analysis enabled the development of segregation and separation function based on the different densities of grain and material other than grain.

  13. Atomically ordered solute segregation behaviour in an oxide grain boundary

    Science.gov (United States)

    Feng, Bin; Yokoi, Tatsuya; Kumamoto, Akihito; Yoshiya, Masato; Ikuhara, Yuichi; Shibata, Naoya

    2016-01-01

    Grain boundary segregation is a critical issue in materials science because it determines the properties of individual grain boundaries and thus governs the macroscopic properties of materials. Recent progress in electron microscopy has greatly improved our understanding of grain boundary segregation phenomena down to atomistic dimensions, but solute segregation is still extremely challenging to experimentally identify at the atomic scale. Here, we report direct observations of atomic-scale yttrium solute segregation behaviours in an yttria-stabilized-zirconia grain boundary using atomic-resolution energy-dispersive X-ray spectroscopy analysis. We found that yttrium solute atoms preferentially segregate to specific atomic sites at the core of the grain boundary, forming a unique chemically-ordered structure across the grain boundary. PMID:27004614

  14. Atomically ordered solute segregation behaviour in an oxide grain boundary

    Science.gov (United States)

    Feng, Bin; Yokoi, Tatsuya; Kumamoto, Akihito; Yoshiya, Masato; Ikuhara, Yuichi; Shibata, Naoya

    2016-03-01

    Grain boundary segregation is a critical issue in materials science because it determines the properties of individual grain boundaries and thus governs the macroscopic properties of materials. Recent progress in electron microscopy has greatly improved our understanding of grain boundary segregation phenomena down to atomistic dimensions, but solute segregation is still extremely challenging to experimentally identify at the atomic scale. Here, we report direct observations of atomic-scale yttrium solute segregation behaviours in an yttria-stabilized-zirconia grain boundary using atomic-resolution energy-dispersive X-ray spectroscopy analysis. We found that yttrium solute atoms preferentially segregate to specific atomic sites at the core of the grain boundary, forming a unique chemically-ordered structure across the grain boundary.

  15. Rapid dynamical mass segregation and properties of fractal star clusters

    CERN Document Server

    Yu, Jincheng; Chen, Li

    2011-01-01

    We investigate the evolution of young star clusters using N-body simulations. We confirm that subvirial and fractal-structured clusters will dynamically mass segregate on a short timescale (within 0.5 Myr). We adopt a modified minimum-spanning-tree (MST) method to measure the degree of mass segregation, demonstrating that the stars escaping from a cluster's potential are important for the temporal dependence of mass segregation in the cluster. The form of the initial velocity distribution will also affect the degree of mass segregation. If it depends on radius, the outer parts of the cluster would expand without undergoing collapse. In velocity space, we find 'inverse mass segregation,' which indicates that massive stars have higher velocity dispersions than their lower-mass counterparts.

  16. Bombardment-induced segregation and redistribution

    International Nuclear Information System (INIS)

    During ion bombardment, a number of processes can alter the compositional distribution and microstructure in near-surface regions of alloys. The relative importance of each process depends principally on the target composition, temperature, and ion characteristics. In addition to displacement mixing leading to a randomization of atomic locations, and preferential loss of alloying elements by sputtering, which are dominant at relatively low temperatures, several thermally-activated processes, including radiation-enhanced diffusion, radiation-induced segregation and Gibbsian adsorption, also play important roles. At elevated temperatures, nonequilibrium point defects induced by ion impacts become mobile and tend to anneal out by recombination and diffusion to extended sinks, such as dislocations, grain boundaries and free surfaces. The high defect concentrations, far exceeding the thermodynamic equilbrium values, can enhance diffusion-controlled processes, while persistent defect fluxes, originating from the spatial non-uniformity in defect production and annihilation, give rise to local redistribution of alloy constituents because of radiation-induced segregation. Moreover, when the alloy is maintained at high temperature, Gibbsian adsorption, driven by the reduction in free energy of the system, occurs even without irradiation; it involves a compositional perturbation in a few atom layers near the alloy surface. The combination of these processes leads to the complex development of a compositionally-modified layer in the subsurface region. In the present paper, selected examples of these different phenomena and their synergistic effects on the evolution of the near-surface compositions of alloys during sputtering and ion implantation at elevated temperatures are discussed. 74 refs., 7 figs., 1 tab

  17. Mitotic segregation in intergeneric hybrids of yeast to give novel genetic segregants

    International Nuclear Information System (INIS)

    Two strains of yeast, Yarrowia lipolytica and Saccharomycopsis fibuligera, have a filamentous growth form in addition to budding cells. Y. lipolytica produces lipases and is used in the production of citric acid while W. fibuligera produces amylases and is used in the production of rice wine. In the present report, we made a study of the following: (i) karyotypes of the two yeast strains to obtain a better understanding of their genetic relatedness, (ii) genetic crosses between the two strains to produce intergeneric hybrids, and (iii) pattern of genetic segregation of the intergeneric hybrids via the mitotic process. The results of our studies showed that the two yeast strains were genetically related and that putative intergeneric hybrids were obtained by a genetic crossing of the strains. The hybrids were relatively stable in mitosis as compared to their parent strains. However, in prolonged vegetative propagation, the hybrids gave rise to genetic segregants, most of which were of either of the two parent phenotypes. A number of the segregants had phenotypes which combined those of the parental types. Of considerable significance was that yet a few others were novel as they exhibited phenotypes not hitherto seen for both parent strains. (author). 9 refs, 5 tabs

  18. White Residential Segregation in U.S. Metropolitan Areas: Conceptual Issues, Patterns, and Trends from the US Census, 1980 to 2010

    OpenAIRE

    Iceland, John; Sharp, Gregory,

    2013-01-01

    Racial and ethnic diversity continues to spread to communities across the United States. Rather than focus on the residential patterns of specific minority or immigrant groups, this study examines changing patterns of white residential segregation in metropolitan America. Using data from the 1980 to 2010 decennial censuses, we calculate levels of white segregation using two common measures, analyze the effect of defining the white population in different ways, and, drawing upon the group thre...

  19. Taylor revisited: Gender segregation and division of labour in the ICT - sector (information and communication technology)

    DEFF Research Database (Denmark)

    Nygaard, Else

    2001-01-01

    Information and communication technology, division of labour, gender segregation, working conditions......Information and communication technology, division of labour, gender segregation, working conditions...

  20. Element segregation on the surfaces of pure aluminum foils

    International Nuclear Information System (INIS)

    The surface segregation trend of trace elements in pure aluminum foils was investigated by density functional theory. The model of nine-layer Al(1 0 0) slab substituted partially by trace element atoms was proposed for calculating surface segregation energy. The calculating results show that (i) B, Mg, Si, Ga, Ge, Y, In, Sn, Sb, Pb and Bi exhibit negative segregation energy and possibly move to the surface, while Be, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu and Zr exhibit positive segregation energies and migrated into the bulk; (ii) the segregation energy was found to be related with the covalent radius, the relaxed position at the surface of the substituting atom and the surface energy; (iii) the segregation behavior of trace element generates lots of defects and dislocation, which can increase the initial pitting nucleation sites in the surface of aluminum foils; (iv) the impurity atom concentration was tested with Pb-doped surfaces, the calculated negative segregation energies in all coverage increases rapidly with the Pb coverage. These conclusions are helpful for designing of the chemical composition and to advance the tunnel etching of aluminum foils.

  1. Factors shaping workplace segregation between natives and immigrants.

    Science.gov (United States)

    Strömgren, Magnus; Tammaru, Tiit; Danzer, Alexander M; van Ham, Maarten; Marcińczak, Szymon; Stjernström, Olof; Lindgren, Urban

    2014-04-01

    Research on segregation of immigrant groups is increasingly turning its attention from residential areas toward other important places, such as the workplace, where immigrants can meet and interact with members of the native population. This article examines workplace segregation of immigrants. We use longitudinal, georeferenced Swedish population register data, which enables us to observe all immigrants in Sweden for the period 1990-2005 on an annual basis. We compare estimates from ordinary least squares with fixed-effects regressions to quantify the extent of immigrants' self-selection into specific workplaces, neighborhoods, and partnerships, which may bias more naïve ordinary least squares results. In line with previous research, we find lower levels of workplace segregation than residential segregation. The main finding is that low levels of residential segregation reduce workplace segregation, even after we take into account intermarriage with natives as well as unobserved characteristics of immigrants' such as willingness and ability to integrate into the host society. Being intermarried with a native reduces workplace segregation for immigrant men but not for immigrant women. PMID:24399142

  2. Temperature and frequency dependent electrical properties of NiCuZn ferrite with CuO-rich grain boundary segregation

    International Nuclear Information System (INIS)

    Highlights: • Sintered NiCuZn ferrite contains CuO-rich segregation along the grain boundaries. • Segregation is allied with different activation energies based on temperature zone. • Both grain boundary and segregated layer posses short-range hopping mechanism. - Abstract: Polycrystalline Ni0.9−yCuyZn0.1Fe1.98O4−δ (y = 0, 0.1 and 0.2) powder was synthesized by conventional solid-state reaction method. X-ray diffraction analysis confirmed single phase cubic spinel phase formation in the calcined powders. An additional phase was observed predominantly after sintering of y = 0.2 compound. The extra phase in the sintered sample is due to the formation of CuO-rich segregation along the grain boundary, which is confirmed by high resolution scanning electron microscopy, X-ray diffraction and energy dispersive X-ray spectroscopy analysis. In order to understand the temperature and frequency dependent electrical properties of segregated ferrite, detailed impedance spectra was investigated on Ni0.7Cu0.2Zn0.1Fe1.98O4−δ in the frequency range of 1 kHz–1 MHz and temperature range of 30–250 °C

  3. Metropolitan racial residential segregation and cardiovascular mortality: exploring pathways.

    Science.gov (United States)

    Greer, Sophia; Kramer, Michael R; Cook-Smith, Jessica N; Casper, Michele L

    2014-06-01

    Racial residential segregation has been associated with an increased risk for heart disease and stroke deaths. However, there has been little research into the role that candidate mediating pathways may play in the relationship between segregation and heart disease or stroke deaths. In this study, we examined the relationship between metropolitan statistical area (MSA)-level segregation and heart disease and stroke mortality rates, by age and race, and also estimated the effects of various educational, economic, social, and health-care indicators (which we refer to as pathways) on this relationship. We used Poisson mixed models to assess the relationship between the isolation index in 265 U.S. MSAs and county-level (heart disease, stroke) mortality rates. All models were stratified by race (non-Hispanic black, non-Hispanic white), age group (35-64 years, ≥ 65 years), and cause of death (heart disease, stroke). We included each potential pathway in the model separately to evaluate its effect on the segregation-mortality association. Among blacks, segregation was positively associated with heart disease mortality rates in both age groups but only with stroke mortality rates in the older age group. Among whites, segregation was marginally associated with heart disease mortality rates in the younger age group and was positively associated with heart disease mortality rates in the older age group. Three of the potential pathways we explored attenuated relationships between segregation and mortality rates among both blacks and whites: percentage of female-headed households, percentage of residents living in poverty, and median household income. Because the percentage of female-headed households can be seen as a proxy for the extent of social disorganization, our finding that it has the greatest attenuating effect on the relationship between racial segregation and heart disease and stroke mortality rates suggests that social disorganization may play a strong role in the

  4. A systematic study of segregation for Zn{sub x}Bi{sub 1−x} liquid binary alloys

    Energy Technology Data Exchange (ETDEWEB)

    Kasem, Md. Riad; Maruf, Md. Helal Uddin [Department of Physics, University of Dhaka, Dhaka (Bangladesh); Bhuiyan, G. M., E-mail: gbhuiyan@du.ac.bd [Department of Theoretical Physics, University of Dhaka, Dhaka (Bangladesh)

    2015-07-21

    We have investigated the segregating properties of Zn{sub x}Bi{sub 1−x} liquid binary alloys through the thermodynamic route that involves both energy of mixing and entropy of mixing. The perturbation approach is used for effective numerical calculations. Results of our calculations agree well with corresponding experimental data for energy and entropy of mixing in the mixed state. The final prediction of segregating properties such as critical concentration and critical temperature also matches reasonably well with experimental data. Most importantly, both energy of mixing and entropy of mixing have produced almost same values for critical concentration and critical temperature of segregation and thus confirm the reliability of the present approach.

  5. Convective influence on radial segregation during unidirectional solidification of the binary alloy HgCdTe

    Energy Technology Data Exchange (ETDEWEB)

    Watring, D.A.; Gillies, D.C.; Lehoczky, S.L.; Szofran, F.R. [Marshall Space Flight Center, Huntsville, AL (United States). Space Sciences Lab.; Alexander, H. [Universities Space Research Association, Huntsville, AL (United States)

    1996-12-31

    In order to simulate the space environment for basic research into the crystal growth mechanism, Hg{sub 0.8}Cd{sub 0.2}Te crystals were grown by the vertical Bridgman-Stockbarger method in the presence of an applied axial magnetic field. The influence of convection, by magneto hydrodynamic damping, on mass transfer in the melt and segregation at the solid-liquid interface was investigated by measuring the axial and radial compositional variations in the grown samples. The reduction of convective mixing in the melt through the application of the magnetic field is found to have a large effect on radial segregation and interface morphology in the grown crystals. Direct comparisons are made with a Hg{sub 0.8}Cd{sub 0.2}Te crystal grown without field and also in the microgravity environment of space during the second United States Microgravity Payload Mission (USMP-2).

  6. Segregation Behaviour of Third Generation Advanced High-Strength Mn-Al Steels

    Directory of Open Access Journals (Sweden)

    A. Grajcar

    2012-04-01

    Full Text Available The paper addresses the macro- and microsegregation of alloying elements in the new-developed Mn-Al TRIP steels, which belong to the third generation of advanced high-strength steels (AHSS used in the automotive industry. The segregation behaviour both in the as-cast state and after hot forging was assessed in the macro scale by OES and by EDS measurements in different structural constituents. The structural investigations were carried out using light and scanning electron microscopy. A special attention was paid to the effect of Nb microaddition on the structure and the segregation of alloying elements. The tendency of Mn and Al to macrosegregation was found. It is difficult to remove in Nb-free steels. Microsegregation of Mn and Al between austenite and ferritic structural constituents can be removed.

  7. Modeling solute segregation during the solidification of γ-phase U-Mo alloys

    Science.gov (United States)

    Steiner, M. A.; Garlea, E.; Agnew, S. R.

    2016-06-01

    Using first principles calculations, it is demonstrated that solute segregation during U-Mo solidification can be modeled using the classic Brody-Fleming limited diffusion framework. The necessary supporting equations specific to the U-Mo alloy, along with careful verification of the assumptions underpinning the Brody-Fleming model are developed, allowing for concentration profile predictions as a function of alloy composition and cooling rate. The resulting model is compared to experimental solute concentration profiles, showing excellent agreement. Combined with complementary modeling of dendritic feature sizes, the solute segregation model can be used to predict the complete microstructural state of individual U-Mo volume elements based upon cooling rates, informing ideal processing routes.

  8. Effect of microstructure on radiation induced segregation and depletion in ion irradiated SS316 steel

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Hyung Ha; Kwon, Sang Chul; Kwon, Jun Hyun [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2011-10-15

    Irradiation assisted stress corrosion cracking (IASCC), void swelling and irradiation induced hardening are caused by change of characteristics of material by neutron irradiation, stress state of material and environmental situation. It has been known that chemical compositions varies at grain boundary (GB) significantly with fluence level and the depletion of Cr element at GB has been considered as one of important factors causing material degradation, especially, IASCC in austenitic stainless steel. However, experimental results of IASCC under PWR condition were directly not connected with Cr depletion phenomenon by neutron irradiation. Because the mechanism of IASCC under PWR has not yet been clearly understood in spite of many energetic researches, fundamental researches about radiation induced segregation and depletion in irradiated austenitic stainless steels have been attracted again. In this work, an effect of residual microstructure on radiation induced segregation and depletion of alloy elements at GB was investigated in ion irradiated SS316 steel using transmission electron microscope (TEM) with energy dispersive spectrometer (EDS)

  9. Preferences, constraints, and the process of sex segregation in college majors: A choice analysis.

    Science.gov (United States)

    Ochsenfeld, Fabian

    2016-03-01

    The persistence of horizontal sex segregation in higher education continues to puzzle social scientists. To help resolve this puzzle, we analyze a sample of college entrants in Germany with a discrete choice design that allows for social learning from the experiences of others. We make at least two contributions to the state of research. First, we test whether essentialist gender stereotypes affect major selection mostly through internalization or rather as external constraints that high school graduates adapt their behavior to. Empirically, we find that internalized vocational interests better explain gendered major choices than conformance with friends' and parents' expectations does. Second, we scrutinize whether segregation results from women's anticipation of gendered family roles or from their anticipation of sex-based discrimination, but we find no evidence for either of these hypotheses. As in most previous studies, differences in mathematics achievement fail to explain gendered patterns of selection into college majors. PMID:26857176

  10. The socioeconomic and ethnic segregation of living conditions in Copenhagen

    DEFF Research Database (Denmark)

    Møller, Iver Hornemann; Larsen, Jørgen Elm

    2015-01-01

    . Differences in income have increased spatial segregation in Copenhagen in terms of housing and education. This segregation is most visible in relation to highly educated Danes and immigrants from non-Western countries. The article first examines poverty at household level and its spatial dimensions. Secondly......The aim of this article is to analyze the discrepancies between certain aspects of living conditions of ethnic Danes and immigrants in Copenhagen. Copenhagen is quite prosperous and fares well in the globalized economy but is at the same time experiencing increasing poverty and ethnic segregation...

  11. The Socioeconomic and Ethnic Segregation of Living Conditions in Copenhagen

    DEFF Research Database (Denmark)

    Møller, Iver Hornemann; Larsen, Jørgen Elm

    The aim of this article is to analyze the discrepancies between certain aspects of living conditions of ethnic Danes and immigrants in Copenhagen. Copenhagen is quite prosperous and fares well in the globalized economy but is at the same time experiencing increasing poverty and ethnic segregation....... Differences in income have increased spatial segregation in Copenhagen in terms of housing and education. This segregation is most visible in relation to highly educated Danes and immigrants from non-Western countries. The article first examines poverty at household level and its spatial dimensions. Secondly...

  12. The Socioeconomic and Ethnic Segregation of Living Conditions in Copenhagen

    DEFF Research Database (Denmark)

    Møller, Iver Hornemann; Larsen, Jørgen Elm

    2015-01-01

    The aim of this article is to analyze the discrepancies between certain aspects of living conditions of ethnic Danes and immigrants in Copenhagen. Copenhagen is quite prosperous and fares well in the globalized economy but is at the same time experiencing increasing poverty and ethnic segregation....... Differences in income have increased spatial segregation in Copenhagen in terms of housing and education. This segregation is most visible in relation to highly educated Danes and immigrants from non-Western countries. The article first examines poverty at household level and its spatial dimensions. Secondly...

  13. Experience on domestic waste segregation in Ghana

    Directory of Open Access Journals (Sweden)

    Osei Bonsu Patterson

    2013-06-01

    Full Text Available Pollution from domestic wastes is a major environmental challenge in Ghana and many developing countries. Most of these countries depend almost entirely on landfills for waste management, which has proved to be expensive, inefficient and unsustainable. A sustainable solution to this problem is productive use of waste such as recycling. The main challenge that may limit recycling in Ghana and some of these countries is that a chunk of the wastes are littered on the environment, and the rest is collected in bulk in the same waste bin, thereby mixing them. The cost of collecting littered wastes, or separating mixed wastes could be prohibitive, making recycling uneconomical. In order to productively utilize wastes, adequate and separate waste bins must be provided for collecting the different components of wastes. However, budgetary constraints may not allow many countries to purchase expansive waste bins for the different components of wastes. Consequently, a simple waste bin, comprising a metal frame on which polypropylene sack (pp-sack can be hanged to collect inorganic wastes has been developed by the author. The waste bin (new bin can be manufactured industrially using plastic or fabricated by local artisans at an affordable price. This document describes the new bin. Experience in collecting organic and inorganic wastes generated in a house in separate waste bins (waste segregation for the past 16 years is also highlighted.

  14. Segregation patterns in gas-fluidized systems

    Science.gov (United States)

    Gilbertson, M. A.; Eames, I.

    2001-04-01

    The formation of segregation patterns in initially homogeneous, fluidized, binary mixtures of particles has been studied. The adjustment of the bed depends on the proportions of fine and coarse particles in the mixture and the gas flow rate relative to the minimum fluidization velocities of the two components. The particles are immobile until the gas flow rate is sufficiently large to fluidize the mixture of particles. When the gas flow rate exceeds this critical value, alternating vertical bands of coarse and fine particles form. At a second critical gas velocity this pattern breaks down and the more familiar pattern of a mixed horizontal band on top of a layer of coarse particles forms. A phase diagram, constructed from experimental observations, shows the conditions for which each of these regimes exists. Its structure is explained in terms of the fluidization and consequent mobility of the mixture components. When horizontal bands are present, the thickness of the lower layer of coarse particles decreases with increasing gas flow rate depending on the proportion of fine particles in the bed. This, and its development, can be understood by analogy with the sedimentation of particles through a turbulent fluid. The experiments imply that the efficiency of mixing by the bubbles in the fluidized bed is very much less than that expected from gas bubbles in a liquid.

  15. New segregation analysis of panic disorder

    Energy Technology Data Exchange (ETDEWEB)

    Vieland, V.J.; Fyer, A.J.; Chapman, T. [Columbia Univ., New York, NY (United States)] [and others

    1996-04-09

    We performed simple segregation analyses of panic disorder using 126 families of probands with DSM-III-R panic disorder who were ascertained for a family study of anxiety disorders at an anxiety disorders research clinic. We present parameter estimates for dominant, recessive, and arbitrary single major locus models without sex effects, as well as for a nongenetic transmission model, and compare these models to each other and to models obtained by other investigators. We rejected the nongenetic transmission model when comparing it to the recessive model. Consistent with some previous reports, we find comparable support for dominant and recessive models, and in both cases estimate nonzero phenocopy rates. The effect of restricting the analysis to families of probands without any lifetime history of comorbid major depression (MDD) was also examined. No notable differences in parameter estimates were found in that subsample, although the power of that analysis was low. Consistency between the findings in our sample and in another independently collected sample suggests the possibility of pooling such samples in the future in order to achieve the necessary power for more complex analyses. 32 refs., 4 tabs.

  16. Why calculated energies of grain boundary segregation are unreliable when segregant solubility is low

    Czech Academy of Sciences Publication Activity Database

    Lejček, Pavel; Šob, Mojmír; Paidar, Václav; Vítek, V.

    2013-01-01

    Roč. 68, č. 6 (2013), s. 547-550. ISSN 1359-6462 R&D Projects: GA ČR GAP108/12/0144; GA ČR(CZ) GAP108/12/0311; GA AV ČR IAA100100920 Grant ostatní: CEITEC(XE) CZ.1.05/1.1.00/02.0068 Institutional support: RVO:68378271 ; RVO:68081723 Keywords : Interface segregation * grain boundary embrittlement * solid solubilitys * DFT Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.968, year: 2013

  17. Use of segregation techniques to reduce stored low level waste

    International Nuclear Information System (INIS)

    This paper describes the use of segregation techniques in reducing the stored Low Level Waste on Intermediate Waste Repository 1, at Angra Nuclear Power Plant Site, from 1701 to 425 drums of compacted waste. (author)

  18. Phase-oriented surface segregation in an aluminium casting alloy

    International Nuclear Information System (INIS)

    There have been many reports of the surface segregation of minor elements, especially Mg, into surface layers and oxide films on the surface of Al alloys. LM6 casting alloy (Al-12%Si) represents a challenging system to examine such segregation as the alloy features a particularly inhomogeneous phase structure. The very low but mobile Mg content (approximately 0.001 wt.%), and the surface segregation of modifiers such as Na, mean the surface composition responds in a complex manner to thermal treatment conditions. X-ray photoelectron spectroscopy (XPS) has been used to determine the distribution of these elements within the oxide film. Further investigation by dynamic secondary ion mass spectrometry (DSIMS) confirmed a strong alignment of segregated Na and Mg into distinct phases of the structure.

  19. A polarity factor takes the lead in chromosome segregation

    OpenAIRE

    Kirkpatrick, Clare; Viollier, Patrick

    2010-01-01

    Several recent studies shed light on how bacteria achieve rapid and accurate chromosome segregation through an interplay of Par-type partitioning systems, cytokinesis regulators and a polarity determinant.

  20. Silica segregation in the Ni/YSZ electrode

    DEFF Research Database (Denmark)

    Hauch, Anne; Jensen, Søren Højgaard; Bilde-Sørensen, Jørgen;

    2007-01-01

    postmortem analyses reveal the reason for the observed passivation, because results from energy-dispersive spectroscopy clearly show evidence that silica-containing impurities have segregated to the hydrogen electrode/electrolyte interface during electrolysis testing. Examples of different microstructures...

  1. Residential Segregation and Social Differentiation in American Urban Areas

    Science.gov (United States)

    Roof, W. Clark; Van Valey, Thomas L.

    1972-01-01

    Reports research designed to resolve a methodological inconsistency in previous studies, by examining the interrelations among several indexes of residential segregation and measures of educational, occupational, and income differentiation in American urban areas as of 1960. (JM)

  2. Schelling model of cell segregation based only on local information

    Science.gov (United States)

    Nielsen, Alexander Valentin; Gade, Annika Lund; Juul, Jeppe; Strandkvist, Charlotte

    2015-11-01

    While biological studies suggest that motility of cells is involved in cell segregation, few computational models have investigated this mechanism. We apply a simple Schelling model, modified to reflect biological conditions, demonstrating how differences in cell motility arising exclusively from differences in the composition of the local environment can be sufficient to drive segregation. The work presented here demonstrates that the segregation behavior observed in the original Schelling model is robust to a relaxation of the requirement for global information and that the Schelling model may yield insight in the context of biological systems. In the model, the time course of cell segregation follows a power law in accord with experimental observations and previous work.

  3. Segregation and sporadic cases in families with Hunter's syndrome.

    Science.gov (United States)

    Machill, G; Barbujani, G; Danieli, G A; Herrmann, F H

    1991-01-01

    Segregation analysis on five samples of families with Hunter's syndrome (158 cases overall) shows that the mutant allele segregates in agreement with Mendelian expectations for an X linked recessive disease, but the proportion of sporadic cases is significantly lower than expected under mutation-selection equilibrium. Heterogeneity among the samples is apparent, but it is caused entirely by a sample of Ashkenazi families, whose segregation pattern has previously been interpreted as supporting the hypothesis of prenatal selection in favour of the pathological allele. Conversely, our joint analysis of the five samples by a maximum likelihood approach does not suggest segregation distortion. Possible reasons for the apparent lack of sporadic cases include the effect of ascertainment bias. PMID:1908009

  4. Microtiter plate tests for segregation of bioluminescent bacteria.

    Science.gov (United States)

    Šimkus, Remigijus; Meškienė, Rita; Ledas, Žilvinas; Baronas, Romas; Meškys, Rolandas

    2016-02-01

    It has been recently shown that bioluminescence imaging can be usefully applied to provide new insights into bacterial self-organization. In this work we employ bioluminescence imaging to record images of nutrient rich liquid cultures of the lux-gene reporter Escherichia coli in microtiter plate wells. The images show that patterns of inhomogenous bioluminescence form along the three-phase contact lines. The paper analyzes the dependencies of the average number of luminous aggregates (clouds) on various environmental factors. In particular, our results show that optimal (neutral) pH and high aeration rates determine the highest mean number of clouds, and that spatiotemporal patterns do not form in the pH buffered suspensions. In addition, a sigmoidal (switch-like) dependence of the number of aggregates on the rate of aeration was observed. The obtained bioluminescence imaging data was interpreted by employing the Keller-Segel-Fisher (KSF) model of chemotaxis and logistic growth, adapted to systems of metabolically flexible (two-state) bacteria. The modified KSF model successfully simulated the observed switch-like responses. The results of the microtiter plate tests and their simulations indicate that the segregation of bacteria with different activities proceeds in the three-phase contact line region. Copyright © 2015 John Wiley & Sons, Ltd. PMID:26039821

  5. Racial residential segregation and risky sexual behavior among non-Hispanic blacks, 2006-2010.

    Science.gov (United States)

    Lutfi, Khaleeq; Trepka, Mary Jo; Fennie, Kristopher P; Ibanez, Gladys; Gladwin, Hugh

    2015-09-01

    Sexually transmitted infections (STIs) including human immunodeficiency virus (HIV) have disproportionately affected the non-Hispanic black population in the United States. A person's community can affect his or her STI risk by the community's underlying prevalence of STIs, sexual networks, and social influences on individual behaviors. Racial residential segregation-the separation of racial groups in a residential context across physical environments-is a community factor that has been associated with negative health outcomes. The objective of this study was to examine if non-Hispanic blacks living in highly segregated areas were more likely to have risky sexual behavior. Demographic and sexual risk behavior data from non-Hispanic blacks aged 15-44 years participating in the National Survey of Family Growth were linked to Core-Based Statistical Area segregation data from the U.S. Census Bureau. Five dimensions measured racial residential segregation, each covering a different concept of spatial variation. Multilevel logistic regressions were performed to test the effect of each dimension on sexual risk behavior controlling for demographics and community poverty. Of the 3643 participants, 588 (14.5%) reported risky sexual behavior as defined as two or more partners in the last 12 months and no consistent condom use. Multilevel analysis results show that racial residential segregation was associated with risky sexual behavior with the association being stronger for the centralization [aOR (95% CI)][2.07 (2.05-2.08)] and concentration [2.05 (2.03-2.07)] dimensions. This suggests risky sexual behavior is more strongly associated with neighborhoods with high concentrations of non-Hispanic blacks and an accumulation of non-Hispanic blacks in an urban core. Findings suggest racial residential segregation is associated with risky sexual behavior in non-Hispanic blacks 15-44 years of age with magnitudes varying by dimension. Incorporating additional contextual factors may

  6. Prokaryotic DNA segregation by an actin-like filament

    DEFF Research Database (Denmark)

    Møller-Jensen, Jakob; Bugge Jensen, Rasmus; Löwe, Jan;

    2002-01-01

    The mechanisms responsible for prokaryotic DNA segregation are largely unknown. The partitioning locus (par) encoded by the Escherichia coli plasmid R1 actively segregates its replicon to daughter cells. We show here that the ParM ATPase encoded by par forms dynamic actin-like filaments with...... point for ParM polymerization. Hence, we provide evidence for a simple prokaryotic analogue of the eukaryotic mitotic spindle apparatus....

  7. Investigation of boron segregation in low carbon steel

    OpenAIRE

    J. Lis; Lis, A; Kolan, C.

    2011-01-01

    Traces of born in the range 0,002-0,009 % are usually added to many grades of steel. The effect of boron on phase transformations and hardenability of low carbon low alloy steels depends on the form of its behavior in solid solution either in segregations or in precipitations. Temperature and cooling rate determine the existence of boron segregations on grain boundaries. In present paper simulations of boron concentrations were calculated with computer programme DICTRA for low carbon 0,08 %C ...

  8. Occupational gender segregation and gender wage gap in Switzerland

    OpenAIRE

    Finzi, Ilaria; Patrick GAGLIARDINI; Maggi, Rico

    2007-01-01

    Traditionally, the gender wage gap has been explained by gender differences in the level of human capital (observed gender wage gap) and by discriminatory forces in the labour market (unobserved gender wage gap). One candidate for explaining part of the unobserved gender wage gap is occupational segregation. In this dissertation we study the characteristics of horizontal and vertical occupational segregation, namely how the different occupational sectors and the different phases of the career...

  9. ON THE ORIGIN OF MASS SEGREGATION IN NGC 3603

    International Nuclear Information System (INIS)

    We present deep Hubble Space Telescope/Wide Field and Planetary Camera 2 photometry of the young HD 97950 star cluster in the giant H II region NGC 3603. The data were obtained in 1997 and 2007 permitting us to derive membership based on proper motions of the stars. Our data are consistent with an age of 1 Myr for the HD 97950 cluster. A possible age spread, if present in the cluster, appears to be small. The global slope of the incompleteness-corrected mass function for member stars within 60'' is Γ = –0.88 ± 0.15, which is flatter than the value of a Salpeter slope of –1.35. The radially varying mass function shows pronounced mass segregation ranging from slopes of –0.26 ± 0.32 in the inner 5'' to –0.94 ± 0.36 in the outermost annulus (40''-60''). Stars more massive than 50 M ☉ are found only in the cluster center. The Λ minimum spanning tree technique confirms significant mass segregation down to 30 M ☉. The dependence of Λ on mass, i.e., that high-mass stars are more segregated than low-mass stars, and the (weak) dependence of the velocity dispersion on stellar mass might imply that the mass segregation is dynamical in origin. While primordial segregation cannot be excluded, the properties of the mass segregation indicate that dynamical mass segregation may have been the dominant process for segregation of high-mass stars.

  10. GRAIN BOUNDARY CORROSION, STRUCTURE AND SEGREGATION IN NICKEL BICRYSTALS

    OpenAIRE

    Vignaud, C.; Beaunier, L.; Biscondi, M.

    1990-01-01

    Nickel bicrystals with tilt boundaries are used to study the influence of the structure of the grain boundaries on the intergranular corrosion. An electrochemical test allows to obtain the evolution of the corrosion versus the misorientation of grains and the repartition of elements segregated during the elaboration and / or heat treatment at 800°C. Auger electron spectroscopy (AES) and scanning electron microscopy (SEM) on intergranular fracture surfaces allows a corrosion-segregation-struc...

  11. Surface, segregation profile for Ni50Pd50(100)

    DEFF Research Database (Denmark)

    Christensen, Asbjørn; Ruban, Andrei; Skriver, Hans Lomholt

    1997-01-01

    system using the coherent potential approximation and obtain an oscillatory segregation profile, in agreement with experiments. We discuss the energetic origin of the oscillatory segregation profile in terms of effective cluster interactions. We include relaxation effects by means of the semi......-empirical effective medium theory, and find that this cannot explain the remaining differences between theory and experiment. (C) 1997 Elsevier Science B.V....

  12. Segregation analysis of microsatellite (SSR) markers in sugarcane polyploids.

    Science.gov (United States)

    Lu, X; Zhou, H; Pan, Y-B; Chen, C Y; Zhu, J R; Chen, P H; Li, Y-R; Cai, Q; Chen, R K

    2015-01-01

    No information is available on segregation analysis of DNA markers involving both pollen and self-progeny. Therefore, we used capillary electrophoresis- and fluorescence-based DNA fingerprinting together with single pollen collection and polymerase chain reaction (PCR) to investigate simple sequence repeat (SSR) marker segregation among 964 single pollens and 288 self-progenies (S1) of sugarcane cultivar LCP 85-384. Twenty SSR DNA fragments (alleles) were amplified by five polymorphic SSR markers. Only one non-parental SSR allele was observed in 2392 PCRs. SSR allele inheritance was in accordance with Mendelian laws of segregation and independent assortment. Highly significant correlation coefficients were found between frequencies of observed and expected genotypes in pollen and S1 populations. Within the S1 population, the most frequent genotype of each SSR marker was the parental genotype of the same marker. The number of genotypes was higher in pollen than S1 population. PIC values of the five SSR markers were greater in pollen than S1 populations. Eleven of 20 SSR alleles (55%) were segregated in accordance with Mendelian segregation ratios expected from pollen and S1 populations of a 2n = 10x polyploid. Six of 20 SSR alleles were segregated in a 3:1 (presence:absence) ratio and were simplex markers. Four and one alleles were segregated in 77:4 and 143:1 ratios and considered duplex and triplex markers, respectively. Segregation ratios of remaining alleles were unexplainable. The results provide information about selection of crossing parents, estimation of seedling population optimal size, and promotion of efficient selection, which may be valuable for sugarcane breeders. PMID:26782486

  13. Pre-Hire Factors and Workplace Ethnic Segregation

    OpenAIRE

    Strömgren, Magnus; Tammaru, Tiit; van Ham, Maarten; Marcinczak, Szymon; Stjernström, Olof; Lindgren, Urban

    2011-01-01

    In addition to neighbourhoods of residence, family and places of work play important roles in producing and reproducing ethnic segregation. Therefore, recent research on ethnic segregation and contact is increasingly turning its attention from residential areas towards other important domains of daily interethnic contact. The key innovation of this paper is to clarify the role of immigrants' pre-hire exposure to natives in the residence, workplace and family domains in immigrant exposure to n...

  14. Measuring residential segregation in urban Mexico: Levels and patterns

    OpenAIRE

    Monkkonen, Paavo

    2010-01-01

    Changing patterns of urban development in Latin America have drawn increasing attention to residential segregation, yet systematic quantitative analysis remains limited. Using data from the Mexican census of 2000, this paper describes spatial patterns and levels of segregation by ethnicity and socioeconomic status in over 100 cities. Findings confirm many recognized patterns; low-income and informally employed households tend to live in peripheral areas of the city, while high-income and form...

  15. Modeling individual-level heterogeneity in racial residential segregation

    OpenAIRE

    Xie, Yu; Zhou, Xiang

    2012-01-01

    We investigate the dynamic relationship between residential choices of individuals and resulting long-term aggregate segregation patterns, allowing for feedback effects of macrolevel neighborhood conditions on residential choices. We reinterpret past survey data on whites’ attitudes about desired neighborhoods as revealing large heterogeneity in whites’ tolerance of black neighbors. Through agent-based modeling, we improve on a previous model of residential racial segregation by introducing i...

  16. Residential Location Theory and the Measurement of Segregation

    OpenAIRE

    Jeffrey S. Zax

    2003-01-01

    Conventional segregation indices indicate complete integration when the proportion of minorities in a metropolitan area is replicated in any subarea. However, this would not occur, even absent discrimination, because majorities and minorities have different distributions of other residence-determining characteristics. Segregation indices derived from predictions of commuting times for blacks, based on white commuting behavior, have a better theoretical foundation, are largely independent of c...

  17. Using Local Statistics to Portray Ethnic Residential Segregation in London

    OpenAIRE

    Ron Johnston; Michael Poulsen; James Forrest

    2009-01-01

    Much has been written about ethnic residential segregation in urban areas, almost all of it deploying single-index numbers to measure the degree of segregation. These give very little detailed appreciation of the extent to which different ethnic groups live apart from each other, and where. This paper suggests that a combination of measures derived from local spatial statistics, which identify the geography of clustering, and a typology of residential areas, which describes the population com...

  18. The Racial Residential Segregation of Black Single Adults Living Alone

    OpenAIRE

    Marsh, Kris; Iceland, John

    2010-01-01

    While many studies have examined the intersection of race and class with residential segregation and residential preferences, very little is known about the role played by household composition in shaping residential patterns. This paper focuses on the residential patterns of a particular kind of household: those consisting of persons single and living alone (SALA). We compare the residential segregation of black SALA households—an important subset of non-family households and a rapidly growi...

  19. Anticipatory Sorting and Gender Segregation in Temporary Employment

    OpenAIRE

    Isabel Fernandez-Mateo; Zella King

    2011-01-01

    We examine the roots of gender segregation in the screening process by using a longitudinal data set of candidates considered for temporary projects at a staffing firm and following their progress through the hiring pipeline. Theories invoked to explain gender segregation across jobs traditionally rely on firm-specific human capital and expectations of future commitment to explain this phenomenon. These do not apply in this setting. Yet we find that the staffing firm is more likely to shortli...

  20. Quantifying Turbulence-Induced Segregation of Inertial Particles

    OpenAIRE

    Calzavarini, E.; Cencini, M.; Lohse, D.; Toschi, F Federico

    2008-01-01

    Particles with density different from that of the advecting turbulent fluid cluster due to the different response of light/heavy particles to turbulent fluctuations. This study focuses on the quantitative characterization of the segregation of dilute poly-disperse inertial particles evolving in turbulent flow, as obtained from Direct Numerical Simulation of the Navier-Stokes equations. We introduce an indicator of segregation amongst particles of different inertia and/or size, from which a le...

  1. A sociological dilemma: Race, segregation and US sociology

    OpenAIRE

    Bhambra, Gurminder K.

    2014-01-01

    US sociology has been historically segregated in that, at least until the 1960s, there were two distinct institutionally organized traditions of sociological thought – one black and one white. For the most part, however, dominant historiographies have been silent on that segregation and, at best, reproduce it when addressing the US sociological tradition. This is evident in the rarity with which scholars such as WEB Du Bois, E Franklin Frazier, Oliver Cromwell Cox, or other ‘African American ...

  2. An EM algorithm for mapping segregation distortion loci

    OpenAIRE

    Zhang Yuan-Ming; Zhu Chengsong

    2007-01-01

    Abstract Background Chromosomal region that causes distorted segregation ratios is referred to as segregation distortion locus (SDL). The distortion is caused either by differential representation of SDL genotypes in gametes before fertilization or by viability differences of SDL genotypes after fertilization but before genotype scoring. In both cases, observable phenotypes are distorted for marker loci in the chromosomal region close to the SDL. Under the quantitative genetics model for viab...

  3. Simultaneous quantitation of serum HBV DNA and HBeAg can distinguish between slow and fast viral responses to antiviral therapy in patients with chronic hepatitis B A quantificação simultânea do DNA VHB e do AgHBe séricos podem distinguir entre resposta viral lenta e rápida à terapêutica anti-viral em pacientes com hepatite crônica B

    Directory of Open Access Journals (Sweden)

    Luiz Caetano da Silva

    2009-10-01

    Full Text Available BACKGROUND: The quantitation of serum HBeAg is not commonly used to monitor viral response to therapy in chronic hepatitis B. METHODS: In this study, 21 patients receiving varying therapies were followed and their viral response monitored by concomitant viral load and HBeAg quantitation in order to study the meaning and the kinetics of both parameters. RESULTS: It was possible to distinguish between three different patterns of viral response. The first was characterized by a simultaneous decrease in serum HBV DNA and HBeAg. The second pattern was characterized by a decrease in serum HBeAg but persistent detection of HBV DNA. The third pattern was characterized by undetectable HBV DNA with persistent HBeAg positivity, which points to a non-response (Pattern III-B except when HBeAg levels showed a slow but steady drop, characterizing a "slow responder" patient (Pattern III-A. CONCLUSIONS: The first pattern is compatible with a viral response. A long-term HBeAg seropositivity with a slow and persistent decrease (Pattern III-A is also compatible with a viral response and calls for a prolongation of anti-viral treatment.INTRODUÇÃO: A quantificação do AgHBe sérico não é habitualmente utilizada para monitorizar a resposta viral ao tratamento da hepatite crônica B. MÉTODOS: Neste estudo, 21 pacientes sob tratamento com diferentes terapias foram acompanhados e a resposta viral monitorizada pela quantificação concomitante da carga viral e do AgHBe a fim de investigar o significado e a cinética de ambos os parâmetros. RESULTADOS: Distinguiram-se três diferentes padrões de resposta viral. O primeiro caracterizou-se pela redução simultânea do HBV DNA e AgHBe séricos. O segundo padrão caracterizou-se por uma redução do AgHBe porém com detecção persistente do HBV DNA. O terceiro padrão caracterizou-se por HBV DNA indetectável com positividade persistente do AgHBe, sugerindo ausência de resposta (Padrão III-B, exceto quando os n

  4. Radiation-induced segregation in Cu-Au alloys

    International Nuclear Information System (INIS)

    Radiation-induced segregation in a Cu-1 at. % Au alloy was investigated using in situ Rutherford Backscattering Spectrometry. Irradiation with 1.8-MeV He produced nonequilibrium Au atom depletion in the near surface region. The amount of segregation was measured as a function of dose, dose rate and temperature. Segregation was observed between 300 and 5000C. For a calculated dose rate of 3.9 x 10-5 dpa/s, the radiation-induced segregation rate peaked near 4000C. Theoretical analysis based on the Johnson-Lam model predicted that the amount of segregation would be directly proportional to dose at the early stage of irradiation, would deviate from linearity with a continuously decreasing slope at intermediate doses, and finally approach a constant value after high doses. The analysis also predicted that the segregation rate would vary as the -1/4th power of the dose rate at constant dose in the low temperature region. These predictions were all verified experimentally. A procedure for extracting relative defect production efficiencies from similar measurements is discussed

  5. A highly efficient measure of mass segregation in star clusters

    CERN Document Server

    Olczak, C; Henning, Th

    2011-01-01

    Investigations of mass segregation are of vital interest for the understanding of the formation and dynamical evolution of stellar systems on a wide range of spatial scales. Our method is based on the minimum spanning tree (MST) that serves as a geometry-independent measure of concentration. Compared to previous such approaches we obtain a significant refinement by using the geometrical mean as an intermediate-pass. It allows the detection of mass segregation with much higher confidence and for much lower degrees of mass segregation than other approaches. The method shows in particular very clear signatures even when applied to small subsets of the entire population. We confirm with high significance strong mass segregation of the five most massive stars in the Orion Nebula Cluster (ONC). Our method is the most sensitive general measure of mass segregation so far and provides robust results for both data from simulations and observations. As such it is ideally suited for tracking mass segregation in young sta...

  6. Evaluating segregation in HSLA steels using computational thermodynamics

    Directory of Open Access Journals (Sweden)

    Meire Guimarães Lage

    2015-10-01

    Full Text Available A low level of segregation in high strength steel plates used to manufacture large diameter pipes is important for the performance of these materials in sour environments. In this work, the level of segregation of different HSLA steels was assessed by computational thermodynamics to identify the most promising compositions. Equilibrium phase diagrams and mass fraction of solid phase diagrams were used to quantify the segregation at the end of solidification. It was verified from the results that S is the stronger segregating element, as expected, but that Nb, C and P also had a considerable segregation. The enrichment of liquid phase with S, P and Nb was related not only to concentration of these elements but also to carbon content. By using only two extreme models – Equilibrium and Scheil–Gulliver – the results will be useful to support the alloy design, especially concerning the evaluation of segregation of C, Mn, S, P, Nb and Ti, which are elements that have a significant influence on mechanical properties and hydrogen embrittlement resistance of HSLA steels used for large diameter pipe.

  7. A Naturalistic Observational Study of Informal Segregation: Seating Patterns in Lectures

    Science.gov (United States)

    Koen, Jennifer; Durrheim, Kevin

    2010-01-01

    In spite of the removal of legislated racial segregation, a number of observational studies in South Africa and elsewhere have shown that "informal," nonlegislated segregation persists in spaces of everyday interaction. Most of these have been case studies of segregation at single sites. The authors seek to quantify segregation in a sample of…

  8. Segregation mechanism of phosphorus in Ti-stabilized interstitial-free steel

    International Nuclear Information System (INIS)

    Highlights: • Segregation mechanism of phosphorus in interstitial-free steel was studied. • The segregation behaviors in IF steel were explained. • Phosphorus segregation had equilibrium segregation characteristics in IF steel. • The content of P and holding temperature strongly influenced segregation behavior. - Abstract: The grain boundary segregation of phosphorus in an interstitial-free (IF) steel aged for different times at 600 and 720 °C was investigated using Auger electron spectroscopy. Results revealed that a significant degree of phosphorus segregation occurred during annealing for Ti-stabilized IF steel with 0.045 wt% bulk content of phosphorus. In addition, the segregation degree increased with increased holding time. The segregation behavior of phosphorus in IF steel was analyzed based on the theory of grain boundary segregation, along with the present experimental data and previous results. The phosphorus segregation had equilibrium segregation characteristics, and the bulk concentration of phosphorus and holding temperature strongly influenced the final grain boundary segregation concentration of phosphorus in IF steel during annealing. Furthermore, the segregation level of phosphorus substantially decreased with increased annealing temperature or decreased bulk concentration of phosphorus. Results of theoretical calculation were consistent with the experimental ones, indicating that the grain boundary segregation behavior of phosphorus in IF steel during annealing can be qualitatively and quantitatively explained by the theory of equilibrium segregation

  9. 49 CFR 176.146 - Segregation from non-hazardous materials.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Segregation from non-hazardous materials. 176.146... VESSEL Detailed Requirements for Class 1 (Explosive) Materials Segregation § 176.146 Segregation from non... for “away from” segregation apply. (2) An explosive substance or article which has a...

  10. 49 CFR 176.144 - Segregation of Class 1 (explosive) materials.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Segregation of Class 1 (explosive) materials. 176... VESSEL Detailed Requirements for Class 1 (Explosive) Materials Segregation § 176.144 Segregation of Class...) Segregation on deck: When Class 1 (explosive) materials in different compatibility groups are carried on...

  11. Linking Radial Species Segregation and Bubbling Patterns in Gas-Fluidized Beds.

    Science.gov (United States)

    Joseph, Gustavo; Hrenya, Christine; Kozlowski, Joe

    2007-11-01

    Binary mixtures of gas-fluidized Geldart Group B particles with size and/or density differences were experimentally investigated at gas velocities up to 3 times the complete fluidization velocities (ufc) of the mixtures. Steady state operation of the bed was ensured prior to data collection. Local bubbling information (mean bubble size, bubble rise velocity, and bubbling frequency) was obtained throughout the bed by means of a backscattered-light optical probe. Segregation data were obtained via bed ``freezing'' and subsequent sieving of layers. Monodisperse runs were also performed as benchmarks for the binary-mixture runs. Perceptible radial variations in species composition were encountered, with the less massive particles tending toward the bed center in most cases. For systems where the species differed in both size and density, the bottom layer presents a reversal of radial segregation pattern at gas velocities below 2ufc. At velocities below 2ufc, bubbling is seen predominantly at the bed periphery, with qualitative differences between monodisperse and mixed systems above 2ufc. A detailed analysis of the bubbling patterns at the various compositions and gas velocities is presented, and links to the observed segregation behavior are made.

  12. Thermal diffusion segregation in granular binary mixtures described by the Enskog equation

    Energy Technology Data Exchange (ETDEWEB)

    Garzo, Vicente, E-mail: vicenteg@unex.es [Departamento de Fisica, Universidad de Extremadura, E-06071 Badajoz (Spain)

    2011-05-15

    The diffusion induced by a thermal gradient in a granular binary mixture is analyzed here in the context of the (inelastic) Enskog equation. Although the Enskog equation neglects velocity correlations among particles that are about to collide, it retains the spatial correlations arising from volume exclusion effects and thus is expected to be applicable for moderate densities. In the steady state with gradients only along a given direction, a segregation criterion is obtained from the thermal diffusion factor {Lambda} by measuring the amount of segregation parallel to the thermal gradient. As expected, the sign of the factor {Lambda} provides a criterion for the transition between the Brazil-nut effect (BNE) and the reverse Brazil-nut effect (RBNE) by varying the parameters of the mixture (the masses and sizes of particles, concentration, solid volume fraction and coefficients of restitution). The form of the phase diagrams for the BNE/RBNE transition is illustrated in detail for several systems, with special emphasis on the significant role played by the inelasticity of collisions. In particular, an effect already found in dilute gases (segregation in a binary mixture of identical masses and sizes but different coefficients of restitution) is extended to dense systems. A comparison with recent computer simulation results reveals good qualitative agreement at the level of the thermal diffusion factor. The present analysis generalizes to arbitrary concentration previous theoretical results derived in the tracer limit case.

  13. Semi-Analytic Model Predictions of Mass Segregation from Groups to Clusters

    CERN Document Server

    Contini, Emanuele

    2015-01-01

    Taking advantage of a set of high-resolution simulations coupled with a state-of-art semi-analytic model of galaxy formation we probe the mass segregation of galaxies in groups and clusters, focusing on which physical mechanisms are driving it. We find evidence of mass segregation in groups and clusters up to the virial radius, with a trend that weakens with increasing halo mass. The physical mechanism responsible for that is found to be dynamical friction, a drag-force that brings more massive galaxies faster towards the innermost regions of the halo. We argue that the intrinsic dependence of dynamical friction timescale on halo mass explains the weakening of mass segregation from groups to clusters. At odds with observational results, we do not find the inclusion of low-mass galaxies in the samples, down to stellar mass $M_* = 10^9 \\, M_{\\odot}$, to change the overall trend shown by intermediate and massive galaxies. Moreover, stellar stripping as well as the growth of galaxies after their accretion, do not...

  14. Simulation of ACE and MACE experiments with a phase segregation model using the TOLBIAC code

    International Nuclear Information System (INIS)

    The paper presents an interpretation of the ACE and MACE MCCI tests with the TOLBIAC code. The phase segregation approach has been introduced in this code. The main physical assumptions are described. Chemical reactions with Zr are believed to be achieved when the ablation of concrete begins. Mass losses from the melt due to melt splattering are taken into account, as well as formation of lateral crusts. The calculated evolution of melt temperature fits well with measurements. The model predicts well the effect of a power increase on the melt temperature; it is stated that the usual model (without phase segregation) approach for heat transfer is not able to reproduce this effect. Sensitivity calculations are performed. It is concluded that initial conditions, melt sparging and presence of lateral crusts have a significant effect on melt temperature; on the contrary, physical properties (viscosity, with reasonable variation range) and power split have a small effect on melt temperature. Finally, the points in favour of the phase segregation approach are summarised. Further development needs for TOLBIAC are also outlined. (orig.)

  15. Additively decomposable segregation indexes. The case of gender segregation by occupations and human capital levels in Spain

    OpenAIRE

    Ruiz-Castillo, Javier; Mora, Ricardo

    2003-01-01

    Building upon the ideas first exposed by Theil and Finizza (1971) and Fuchs (1975), this paper presents an additively decomposable segregation index based on the entropy concept used in information theory. For any pair of classification variables in a given year, the index is decomposed into a between-group and a within-group term. To analyze intertemporal changes in gender segregation for a given partition, the index is decomposed into two terms that capture, respectively, gender composition...

  16. Segregation of Children Who Migrate to the U.S. From Puerto Rico

    Directory of Open Access Journals (Sweden)

    Luis M. Laosa

    2001-01-01

    Full Text Available This study examined patterns of school segregation (ethnic/racial, linguistic, and socioeconomic and other ecological characteristics of the schools that preadolescent children who migrate from Puerto Rico to the United States (New Jersey attend in this country during the first two years following their arrival (N = 89 schools. The data show that Hispanics/Latinos are the majority of the student body in 43% of the schools; African Americans, in 30% of the schools; and European Americans, in 12% of the schools. Native speakers of Spanish are the majority of the student body in 29% of the schools. Approximately one half of the schools are in economically depressed, highly urbanized areas. Although the schools are on average large, 44% of them enroll above capacity. In most schools the majority of the student body is from economically impoverished families with low levels of parental education. There are, however, wide differences among the schools on each of these variables. Correlations show that the higher a student body's proportion of Hispanics/Latinos or native speakers of Spanish, the higher is the student body's proportion of pupils from economically impoverished households with low levels of parental education, and the higher the school's likelihood of being crowded and of being located in a poor inner-city area. Similarly, the higher a student body's proportion of African Americans, the higher is the student body's proportion of pupils from low-income families, and the higher the school's likelihood of being in a poor inner-city area. The findings are discussed with regard to implications for policy and hypotheses in need of research concerning possible consequences of school segregation for students' academic, linguistic, social, and emotional development. Also presented is a historical overview, to the present, and discussion of U.S. policies and judicial decisions concerning school segregation, with particular reference to segregation

  17. Conditioning of Radioactive Wastes Prior to disposal; Segregation and Repackaging

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Il Sik; Kim, Ki Hong; Hong, Dae Seok; Lee, Bum Chul [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    We stored several types of radioactive wastes at interim storage facility of KAERI ; the combustible wastes (cloths, decontamination paper and vinyls) from Hanaro multipurpose research reactor, nuclear fuel cycle facility, RI production facility and laboratories, and the non-combustible wastes (metals and glass) dismantled and discarded from the apparatus of laboratories which deteriorated, and also the miscellaneous wastes (spent air-filters). After a segregation of these wastes as the same type, they were treated by using a proper method in order to meet both the national regulation and the waste acceptance criteria of Kyung-ju disposal site. For a safe disposal of waste drums, the waste characterization system including a scaling factor which is hard to measure special radionuclides is established completely. All data of those repackaged drums were input into an ANSIM system so that we could manage them clearly and effectively such like an easy transparent traceability. Through a decontamination of empty drums generated in a repackaging process of the stored drums, these drums can be reused or compressed to reduce their volume reduction for disposal. As a result, the space to store radioactive waste drums are secured more than before, and also the interim storage facility are maintained in a good state. The combustible wastes, which stored at the interim storage facility of KAERI, are managed safely in compliance with the specifications of the national regulations and disposal site. Through the classification and repackage of them, the storage space of drums at RWTF was secured more than before, and the storage facility was kept in a good state, and also the disposal cost of all stored waste drums of KAERI will be reduced due to the reduction of waste volume. Base on the experiences, the non-combustible wastes will be treated soon.

  18. Conditioning of Radioactive Wastes Prior to disposal; Segregation and Repackaging

    International Nuclear Information System (INIS)

    We stored several types of radioactive wastes at interim storage facility of KAERI ; the combustible wastes (cloths, decontamination paper and vinyls) from Hanaro multipurpose research reactor, nuclear fuel cycle facility, RI production facility and laboratories, and the non-combustible wastes (metals and glass) dismantled and discarded from the apparatus of laboratories which deteriorated, and also the miscellaneous wastes (spent air-filters). After a segregation of these wastes as the same type, they were treated by using a proper method in order to meet both the national regulation and the waste acceptance criteria of Kyung-ju disposal site. For a safe disposal of waste drums, the waste characterization system including a scaling factor which is hard to measure special radionuclides is established completely. All data of those repackaged drums were input into an ANSIM system so that we could manage them clearly and effectively such like an easy transparent traceability. Through a decontamination of empty drums generated in a repackaging process of the stored drums, these drums can be reused or compressed to reduce their volume reduction for disposal. As a result, the space to store radioactive waste drums are secured more than before, and also the interim storage facility are maintained in a good state. The combustible wastes, which stored at the interim storage facility of KAERI, are managed safely in compliance with the specifications of the national regulations and disposal site. Through the classification and repackage of them, the storage space of drums at RWTF was secured more than before, and the storage facility was kept in a good state, and also the disposal cost of all stored waste drums of KAERI will be reduced due to the reduction of waste volume. Base on the experiences, the non-combustible wastes will be treated soon

  19. Segregation, Education and Space - a Case Study of Malmö

    OpenAIRE

    Persson, Rickard

    2008-01-01

    This dissertation takes its point of departure in two questions about segregation and its implications for architectural research. The first question is whether examining segregation in terms of education is a fruitful tool for analyzing segregation in general. In answering that question, the dissertation describes how educational segregation relates to segregation by income, ethnicity and age. This first question is analyzed with the aid of the theoretical framework created by Pierre Bourdie...

  20. Intergranular segregation of Cr in Ti-stabilized low-Cr ferritic stainless steel

    International Nuclear Information System (INIS)

    The precipitation and segregation phenomenon in a type 409L Ti-stabilized 11 wt.% Cr ferritic stainless steel has been investigated using transmission electron microscopy and a laser-assisted three-dimensional atom probe. In solution-treated and aged specimens, a strong segregation and consequent depletion of Cr was observed, as well as segregation of C and Ti atoms along the grain boundary. The reason for the Cr segregation and the way to avoid such segregation is discussed.

  1. Residential segregation, dividing walls and mental health: A population-based record linkage study

    OpenAIRE

    Maguire, Aideen; French, Declan; O'Reilly, Dermot

    2016-01-01

    BackgroundNeighbourhood segregation has been described as a fundamental determinant of physical health, but literature on its effect on mental health is less clear. Whilst most previous research has relied on conceptualized measures of segregation, Northern Ireland is unique as it contains physical manifestations of segregation in the form of segregation barriers (or “peacelines”) which can be used to accurately identify residential segregation. MethodsWe used population-wide health record da...

  2. Study on segregation of aluminium-uranium alloys

    International Nuclear Information System (INIS)

    The relations between alloy solidification and solute segregation were considered. The solidification structure and the solute redistribution during the solidification of alloys with dendritic micro morphology were studied. The macro and micro segregation theories were reviewed. The mechanisms that could change the solidification structure were taken into account in the context of more homogeneous alloy production. Aluminum alloys solidification structures and segregation were studied experimentally in the 13 to 45% uranium range, usually considering solidification in static molds. The uranium alloys with up to 20% uranium were studied both for solidification in ingot molds and for controlled directional solidification. It was verified that these alloy compositions had structures similar to those of hipoeutectic alloys, showing an a phase with dendritic morphology and inter dendritic eutectic. For the alloys with more than 25% uranium, it was observed the formation of UAl3 and UAl4 phases with dendritic morphology. The dendritic UAl3, phase morphology was affected both by the solute concentration in the alloy and by the growth rate. The dendritic UAl3 phase non-singular aspect could be destroyed with decrease of the alloy solute concentration. In the alloys obtained with higher cooling rates it was found a tendency for the formation of substantial quantities of equi axial crystals of the solute enriched phases in the central regions of the ingot upper half. In the more external regions it was observed dendritic growth of these phases, for alloy compositions with over 25% uranium. An adequate reduction in the cooling rate changed the solidification structure form and distribution, as well as the segregation type and intensity. The uranium content in the solidified macro structures is presented as a function of: cooling rate, superheating, mold size, mold form and its temperature, number of remelting and time for the melt homogenization and agitation. It was observed

  3. 2015年下半年美国FDA批准的新分子实体与评价:心血管和精神系统疾病、抗病毒感染、女性性欲低下障碍、糖尿病治疗用药和化疗止吐药%Updates of New Molecular Entities Approved by the FDA in the Second-Half of 2015:Cardiovascular, Psychiatric, Anti-Viral, Hypoactive Sexual Desire Disorder, Diabetesand Chemotherapy-induced Emesis

    Institute of Scientific and Technical Information of China (English)

    孙树森; 赵志刚

    2016-01-01

    2015年下半年,FDA批准了31个新分子实体和新生物制品。本文介绍和评价心血管和精神系统疾病、抗病毒感染、女性性欲低下障碍、糖尿病治疗用药和化疗止吐药。%The US FDA approved 31 new molecular entities and new therapeutic biological products in the second-half of 2015. This article provides an update and evaluation of the new drugs approved for the treatment of cardiovascular and psychiatric diseases, anti-viral infections, hypoactive sexual desire disorder, diabetes and chemotherapy-induced emesis.

  4. Segregation in quasi-two-dimensional granular systems

    International Nuclear Information System (INIS)

    Segregation for two granular species is studied numerically in a vertically vibrated quasi-two-dimensional (quasi-2D) box. The height of the box is smaller than two particle diameters so that particles are limited to a submonolayer. Two cases are considered: grains that differ in their density but have equal size, and grains that have equal density but different diameters, while keeping the quasi-2D condition. It is observed that in both cases, for vibration frequencies beyond a certain threshold-which depends on the density or diameter ratios-segregation takes place in the lateral directions. In the quasi-2D geometry, gravity does not play a direct role in the in-plane dynamics and gravity does not point to the segregation directions; hence, several known segregation mechanisms that rely on gravity are discarded. The segregation we observe is dominated by a lack of equipartition between the two species; the light particles exert a larger pressure than the heavier ones, inducing the latter to form clusters. This energy difference in the horizontal direction is due to the existence of a fixed point characterized by vertical motion and hence vanishing horizontal energy. Heavier and bigger grains are more rapidly attracted to the fixed point and the perturbations are less efficient in taking them off the fixed point when compared to the lighter grains. As a consequence, heavier and bigger grains have less horizontal agitation than lighter ones. Although limited by finite size effects, the simulations suggest that the two cases we consider differ in the transition character: one is continuous and the other is discontinuous. In the cases where grains differ in mass on varying the control parameter, partial segregation is first observed, presenting many clusters of heavier particles. Eventually, a global cluster is formed with impurities; namely lighter particles are present inside. The transition looks continuous when characterized by several segregation order

  5. Segregation in quasi-two-dimensional granular systems

    Science.gov (United States)

    Rivas, Nicolás; Cordero, Patricio; Risso, Dino; Soto, Rodrigo

    2011-05-01

    Segregation for two granular species is studied numerically in a vertically vibrated quasi-two-dimensional (quasi-2D) box. The height of the box is smaller than two particle diameters so that particles are limited to a submonolayer. Two cases are considered: grains that differ in their density but have equal size, and grains that have equal density but different diameters, while keeping the quasi-2D condition. It is observed that in both cases, for vibration frequencies beyond a certain threshold—which depends on the density or diameter ratios—segregation takes place in the lateral directions. In the quasi-2D geometry, gravity does not play a direct role in the in-plane dynamics and gravity does not point to the segregation directions; hence, several known segregation mechanisms that rely on gravity are discarded. The segregation we observe is dominated by a lack of equipartition between the two species; the light particles exert a larger pressure than the heavier ones, inducing the latter to form clusters. This energy difference in the horizontal direction is due to the existence of a fixed point characterized by vertical motion and hence vanishing horizontal energy. Heavier and bigger grains are more rapidly attracted to the fixed point and the perturbations are less efficient in taking them off the fixed point when compared to the lighter grains. As a consequence, heavier and bigger grains have less horizontal agitation than lighter ones. Although limited by finite size effects, the simulations suggest that the two cases we consider differ in the transition character: one is continuous and the other is discontinuous. In the cases where grains differ in mass on varying the control parameter, partial segregation is first observed, presenting many clusters of heavier particles. Eventually, a global cluster is formed with impurities; namely lighter particles are present inside. The transition looks continuous when characterized by several segregation order

  6. Theory for shear-induced segregation of dense granular mixtures

    International Nuclear Information System (INIS)

    It is well known that a mixture of different sized particles will segregate in a gravitational field. However, it has only recently been shown that a gradient of shear rate alone can drive segregation in dense sheared systems. In contrast with sparse energetic granular materials, in dense sheared systems, large particles segregate to regions with higher shear rates. In this paper, we develop a model for shear-induced segregation in dense mixtures of different sized particles. The model is comprised of two primary parts. The first involves the tendency of a gradient in kinetic stress-stress associated with velocity fluctuation correlations-to drive all particles toward regions of low shear rate. The second is essentially a kinetic sieving effect in which small particles are more likely than large particles to find voids into which they can travel. The two features together segregate small particles to regions of low shear rate and squeeze large particles in the opposite direction. We validate this model via three-dimensional discrete element method simulations in a vertical chute.

  7. Hydrogen embrittlement for austenitic alloys: behaviour of microstructure and segregation of sulphur and phosphorus impurities

    International Nuclear Information System (INIS)

    The mechanical properties of austenitic alloys can be highly modified in the presence of a hydrogenation. The purpose of this study is to specify this influence on two alloys (800 and 600) for which the chemical composition on the one hand, and the microstructure on the other hand have significant differences. The hydrogenation was done before tensile testing under potentiostatic cathodic polarization at 300 deg c for times varying between 5 and 48 h. A high embrittlement from the hydrogen was shown in the case of the alloy 600 in the quenched annealed state with precipitates at the grain boundaries. It is lower in the quenched state without precipitates at the grain boundaries. On the other hand, the alloy 800 is not embrittled by the hydrogen, neither in the quenched state nor in the annealed state, even in the presence of precipitates. The influence of a phosphorus segregation on the grain boundaries can explain the differences observed. (authors)

  8. Thermal diffusion segregation of an impurity in a driven granular fluid

    International Nuclear Information System (INIS)

    We study segregation of an impurity in a driven granular fluid under two types of steady states. In the first state, the granular gas is driven by a stochastic volume force field with a Fourier-type profile while in the second state, the granular gas is sheared in such a way that inelastic cooling is balanced by viscous heating. We compare theoretical results derived from a solution of the (inelastic) Boltzmann equation at Navier-Stokes (NS) order with those obtained from the Direct Monte Carlo simulation (DSMC) method and molecular dynamics (MD) simulations. Good agreement is found between theory and simulation, which provides strong evidence of the reliability of NS granular hydrodynamics for these steady states (including the dynamics of the impurity), even at high inelasticity. In addition, preliminary results for thermal diffusion in granular fluids at moderate densities are also presented. As for dilute gases, excellent agreement is also found in this more general case

  9. Thermal diffusion segregation of an impurity in a driven granular fluid

    Energy Technology Data Exchange (ETDEWEB)

    Reyes, Francisco Vega; Garzó, Vicente [Departamento de Física, Universidad de Extremadura, E-06071 Badajoz, Spain and Instituto de Computación Científica Avanzada (ICCAEx), Universidad de Extremadura, E-06071 Badajoz (Spain)

    2014-12-09

    We study segregation of an impurity in a driven granular fluid under two types of steady states. In the first state, the granular gas is driven by a stochastic volume force field with a Fourier-type profile while in the second state, the granular gas is sheared in such a way that inelastic cooling is balanced by viscous heating. We compare theoretical results derived from a solution of the (inelastic) Boltzmann equation at Navier-Stokes (NS) order with those obtained from the Direct Monte Carlo simulation (DSMC) method and molecular dynamics (MD) simulations. Good agreement is found between theory and simulation, which provides strong evidence of the reliability of NS granular hydrodynamics for these steady states (including the dynamics of the impurity), even at high inelasticity. In addition, preliminary results for thermal diffusion in granular fluids at moderate densities are also presented. As for dilute gases, excellent agreement is also found in this more general case.

  10. Segregation of ruthenium to edge dislocations in uranium dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Goyal, Anuj; Rudzik, Thomas; Deng, Bowen; Hong, Minki; Chernatynskiy, Aleksandr; Sinnott, Susan B.; Phillpot, Simon R., E-mail: sphil@mse.ufl.edu

    2013-10-15

    Atomic-level simulation methods are used to determine the interaction of a metallic fission product, Ru{sup 4+}, with the core of a{sub o}/2〈1 1 0〉{1 1 0} and a{sub o}/2〈1 1 0〉{0 0 1} edge dislocations in UO{sub 2}, experimentally the most active slip systems. Specifically, the segregation behavior of Ru{sup 4+} is examined at the cationic substitution site; comparisons are made with both continuum-elastic results and with the results of atomistic simulations on strained single crystals. The results on strained single crystals suggest that segregation behavior is a strong function of the elastic strain field around the detailed atomic structure at the dislocation core. Furthermore, the segregation is affected by the orientation of the dislocation and electrostatic interactions at the atomic defect site.

  11. Organization of texture segregation processing in primate visual cortex.

    Science.gov (United States)

    Lamme, V A; van Dijk, B W; Spekereijse, H

    1993-01-01

    We investigated the intracortical organization of neuronal mass activity that is related to texture segregation on the basis of orientation contrast. Evoked potentials were recorded to a stimulus, signalling a contribution from texture segregation-sensitive mechanisms by means of specific response components. The specific components could only be recorded when textons had a spatial organization that leads to the percept of image segmentation. Equivalent dipole estimations of the specific response components suggested the presence of texture segregation-related activity in the primary visual cortex. These results were corroborated by current-source-density analysis of intracortical recordings in the awake monkey. A specific involvement of layers 2/3 and 5 of area 17 in the global process of image segmentation could be demonstrated. PMID:8217932

  12. Early selection of agronomic traits in segregating black bean populations

    Directory of Open Access Journals (Sweden)

    Juliano Garcia Bertoldo

    2010-01-01

    Full Text Available This study evaluated the agronomic performance of six segregating populations of black bean (BRS Supremo x CHP 97-01, BRS Supremo x CHP 97-04, BRS Supremo x CHP 97-05-16, BRS Supremo x CHP 97-26, BRS Supremo x IPR Graúna and BRS Supremo x Uirapuru IPR in the F3 generation, conducted by the bulk method. Populations and parents were evaluated in the 2007/08 growing season in a randomized block design with four replications. Results show promising traits of the segregating population BRS Supremo x CHP 97-04, which was superior to parent BRS Supremo, indicating the line for further selection. The segregating populations and their parents were grouped by Ward’s method, indicating the similarity of the selected lines.

  13. Segregation of ruthenium to edge dislocations in uranium dioxide

    International Nuclear Information System (INIS)

    Atomic-level simulation methods are used to determine the interaction of a metallic fission product, Ru4+, with the core of ao/2〈1 1 0〉{1 1 0} and ao/2〈1 1 0〉{0 0 1} edge dislocations in UO2, experimentally the most active slip systems. Specifically, the segregation behavior of Ru4+ is examined at the cationic substitution site; comparisons are made with both continuum-elastic results and with the results of atomistic simulations on strained single crystals. The results on strained single crystals suggest that segregation behavior is a strong function of the elastic strain field around the detailed atomic structure at the dislocation core. Furthermore, the segregation is affected by the orientation of the dislocation and electrostatic interactions at the atomic defect site

  14. Quantification of interfacial segregation by analytical electron microscopy

    CERN Document Server

    Muellejans, H

    2003-01-01

    The quantification of interfacial segregation by spatial difference and one-dimensional profiling is presented in general where special attention is given to the random and systematic uncertainties. The method is demonstrated for an example of Al-Al sub 2 O sub 3 interfaces in a metal-ceramic composite material investigated by energy-dispersive X-ray spectroscopy and electron energy loss spectroscopy in a dedicated scanning transmission electron microscope. The variation of segregation measured at different interfaces by both methods is within the uncertainties, indicating a constant segregation level and interfacial phase formation. The most important random uncertainty is the counting statistics of the impurity signal whereas the specimen thickness introduces systematic uncertainties (via k factor and effective scan width). The latter could be significantly reduced when the specimen thickness is determined explicitly. (orig.)

  15. Racial Residential Segregation and Disparities in Obesity among Women.

    Science.gov (United States)

    Bower, Kelly M; Thorpe, Roland J; Yenokyan, Gayane; McGinty, E Emma E; Dubay, Lisa; Gaskin, Darrell J

    2015-10-01

    The high rate of obesity among black women in the USA is a significant public health problem. However, there is limited research on the relationship between racial residential segregation and disparities in obesity, and the existing evidence is limited and results are mixed. This study examines the relationship between racial residential segregation and obesity among black and white women. We conducted this cross-sectional study by joining data from the 1999-2004 National Health and Nutrition Examination Survey with data from the 2000 US Census. Multilevel logistic regression models found that for every one-point increase in the black isolation index, there was a 1.06 (95 % confidence interval (CI) = 1.01, 1.11) times higher odds of obesity for black women. In order to address the disparately high rates of obesity among black women, health policies need to address the economic, political, and social forces that produce racially segregated neighborhoods. PMID:26268731

  16. Segregation in the Atmospheric Boundary Layer - A Discussion

    Science.gov (United States)

    Dlugi, Ralph; Berger, Martina; Zelger, Michael; Hofzumahaus, Andreas; Rohrer, Franz; Holland, Frank; Lu, Keding; Tsokankunku, Anywhere; Sörgel, Matthias; Kramm, Gerhard; Mölders, Nicole

    2016-04-01

    Segregation is a well known topic in technical chemistry and means an incomplete mixing of the reactants. Incomplete mixing reduces the rate of reaction which is of utmost importance in technical chemistry but has been payed less attention in atmospheric chemistry. Different observational and modelling studies on chemical reactions in the turbulent and convective atmospheric boundary layer are analysed for the influences of segregation in the systems NO ‑ NO2 ‑ O3 and OH + V OCs (with main focus on isoprene). Also some estimates on reactions like HO2 + NO (an important recycling mechanism for OH) will be given. Especially, different terms of the intensity of segregation IS (correlation coefficients, standard deviations of mixing ratios) are compared and are related to characteristics of the flow regimes, such as mixing conditions and Damköhler numbers. Also influences of fluctuations of actinic fluxes are discussed which influence the mostly photo chemically driven reactions that were investigated.

  17. Segregation effects and phase developments during solidification of alloy 625

    DEFF Research Database (Denmark)

    Højerslev, Christian; Tiedje, Niels Skat; Hald, John

    2006-01-01

    material contained gamma-phase, Laves phase and, if carbon was dissolved in the liquid, niobium rich carbides formed. Molybdenum and niobium showed strong tendencies to segregate. Their segregation was balanced by inverse segregation of nickel and iron. The chromium concentration remained almost constant...... in gamma in the entire matrix material. Addition of carbon did not cause detectable alterations of the material that experienced planar front solidification. However, it promoted the formation of niobium rich carbides in the material that solidified eutectic-like. Thus, this material differed from...... that of the pure sample in constitution, and consequently in gamma-phase composition. Niobium rich carbides formed prior to Laves phase; in carbon rich volumes only the carbides form. As compared to the pure sample, the sample enriched in iron had decreased global minimal solute concentration in the...

  18. Spatial Boundaries and the Local Context of Residential Segregation

    CERN Document Server

    Roberto, Elizabeth

    2015-01-01

    Spatial boundaries are a defining feature of a city's social and spatial organization. Rivers, highways, and train tracks create excess distance between nearby locations and often mark social separation -- they become dividing lines that are well known to residents. Qualitative studies are rich with insight about the local significance of boundaries, but they have been largely ignored in the quantitative segregation literature. I advance existing scholarship by integrating spatial boundaries into the way we measure residential segregation for city populations. I introduce a new method that measures the proximity of residential locations and the reach of local environments around each location using road distance. This is more realistic than straight line ("as the crow flies") distance, because it captures the connectivity of roads and the distance imposed by physical boundaries. I measure segregation using the Divergence Index, which evaluates how surprising the composition of each local environment is given ...

  19. Helium segregation on surfaces of plasma-exposed tungsten

    International Nuclear Information System (INIS)

    We report a hierarchical multi-scale modeling study of implanted helium segregation on surfaces of tungsten, considered as a plasma facing component in nuclear fusion reactors. We employ a hierarchy of atomic-scale simulations based on a reliable interatomic interaction potential, including molecular-statics simulations to understand the origin of helium surface segregation, targeted molecular-dynamics (MD) simulations of near-surface cluster reactions, and large-scale MD simulations of implanted helium evolution in plasma-exposed tungsten. We find that small, mobile Hen (1  ⩽  n  ⩽  7) clusters in the near-surface region are attracted to the surface due to an elastic interaction force that provides the thermodynamic driving force for surface segregation. This elastic interaction force induces drift fluxes of these mobile Hen clusters, which increase substantially as the migrating clusters approach the surface, facilitating helium segregation on the surface. Moreover, the clusters’ drift toward the surface enables cluster reactions, most importantly trap mutation, in the near-surface region at rates much higher than in the bulk material. These near-surface cluster dynamics have significant effects on the surface morphology, near-surface defect structures, and the amount of helium retained in the material upon plasma exposure. We integrate the findings of such atomic-scale simulations into a properly parameterized and validated spatially dependent, continuum-scale reaction-diffusion cluster dynamics model, capable of predicting implanted helium evolution, surface segregation, and its near-surface effects in tungsten. This cluster-dynamics model sets the stage for development of fully atomistically informed coarse-grained models for computationally efficient simulation predictions of helium surface segregation, as well as helium retention and surface morphological evolution, toward optimal design of plasma facing components. (paper)

  20. Helium segregation on surfaces of plasma-exposed tungsten

    Science.gov (United States)

    Maroudas, Dimitrios; Blondel, Sophie; Hu, Lin; Hammond, Karl D.; Wirth, Brian D.

    2016-02-01

    We report a hierarchical multi-scale modeling study of implanted helium segregation on surfaces of tungsten, considered as a plasma facing component in nuclear fusion reactors. We employ a hierarchy of atomic-scale simulations based on a reliable interatomic interaction potential, including molecular-statics simulations to understand the origin of helium surface segregation, targeted molecular-dynamics (MD) simulations of near-surface cluster reactions, and large-scale MD simulations of implanted helium evolution in plasma-exposed tungsten. We find that small, mobile He n (1  ⩽  n  ⩽  7) clusters in the near-surface region are attracted to the surface due to an elastic interaction force that provides the thermodynamic driving force for surface segregation. This elastic interaction force induces drift fluxes of these mobile He n clusters, which increase substantially as the migrating clusters approach the surface, facilitating helium segregation on the surface. Moreover, the clusters’ drift toward the surface enables cluster reactions, most importantly trap mutation, in the near-surface region at rates much higher than in the bulk material. These near-surface cluster dynamics have significant effects on the surface morphology, near-surface defect structures, and the amount of helium retained in the material upon plasma exposure. We integrate the findings of such atomic-scale simulations into a properly parameterized and validated spatially dependent, continuum-scale reaction-diffusion cluster dynamics model, capable of predicting implanted helium evolution, surface segregation, and its near-surface effects in tungsten. This cluster-dynamics model sets the stage for development of fully atomistically informed coarse-grained models for computationally efficient simulation predictions of helium surface segregation, as well as helium retention and surface morphological evolution, toward optimal design of plasma facing components.

  1. Solute segregation on Σ3 and random grain boundaries in type 316L stainless steel

    International Nuclear Information System (INIS)

    Solute segregation and impurity segregation on random and Σ3 grain boundaries in a type 316L stainless steel were investigated by means of atom probe tomography (APT). Segregation of Mo, P, B, and C was observed on random grain boundaries, irrespective of grain boundary misorientation. Two-dimensional concentration maps along the grain boundary plane revealed that the concentrations of all segregated elements were not homogeneous and no co-segregation was observed. In contrast, no segregation was observed on Σ3 grain boundaries

  2. Sex Segregation and Wage Gaps in East and West Germany

    OpenAIRE

    Stepan Jurajda; Heike Harmgart

    2002-01-01

    In this paper we examine occupational and firm-level sex segregation and their relationship with wages in West Germany and in East Germany, where anti- discrimination policies were recently implemented. We employ a representative sample of social-security wage records from 1992 and 1995, including a matched employer-employee sub-sample. We find large differences in the size of the wage gap, but not in the degree of segregation across the two parts of Germany. In contrast to U.S. literature Ge...

  3. Flow Induced segregation in full scale castings with SCC

    DEFF Research Database (Denmark)

    Thrane, Lars Nyholm; Stang, Henrik; Geiker, Mette Rica

    2007-01-01

    Though promising, pioneering work has been carried out with rheological characterization and numerical modelling of form filling with SCC, the approach is far from standard in the concrete industry and clearly the approach does not yet hold all the answers to relevant questions. In particular flow...... patterns during form filling. Results show that the flow patterns have a major influence on the risk of flow induced segregation and the surface finish of the hardened concrete. A hypothesis for the mechanism of flow induced segregation is put forth....

  4. Stripe segregation and magnetic coupling in the nickelate La 5/3Sr1/3NiO4

    KAUST Repository

    Schwingenschlögl, Udo

    2009-03-02

    We investigate the consequences of the stripe formation in the nickelate La5/3Sr1/3NiO4 for the details of its crystal structure and electronic states. Our data are based on numerical simulations within density functional theory (DFT) and the generalized gradient approximation (GGA). The on-site Coulomb interaction is included in terms of the LDA+U scheme. Structure optimization of preliminary experimental data indicates a strong interaction between the structural and electronic degrees of freedom. In particular, we find a segregation of the diagonal filled stripes induced by a delicate interplay with the magnetic coupling. Beyond the cooperative effect of stripe segregation and spin order, distinct octahedral distortions are essential for the formation of an insulating state. © 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Isothermal Gravitational Segregation: Algorithms and Specifications

    DEFF Research Database (Denmark)

    Halldórsson, Snorri; Stenby, Erling Halfdan

    2000-01-01

    New algorithms for calculating the isothermal equilibrium state of reservoir fluids under the influence of gravity are presented. Two types of specifications are considered: the specification of pressure and composition at a reference depth; and the specification of the total overall content of t...

  6. Residential segregation and spatial distribution of a non-labor force population: the needy elderly and disabled.

    Science.gov (United States)

    Massey, D S

    1980-01-01

    "Processes of urban change [in the United States] were hypothesized to have created a segregated residential distribution typified by a concentration of disadvantaged and chronically unemployed individuals in decaying inner cities and the employed middle class in suburbs. This hypothesis was tested in one heavily urbanized area for a non-labor force population of needy elderly and disabled persons." Data were obtained from the Fourth Count Summary Tapes of the 1970 census PMID:12263197

  7. The Racial/Ethnic Distribution of Heat Risk–Related Land Cover in Relation to Residential Segregation

    OpenAIRE

    Morello-Frosch, Rachel Adele; Jesdale, Bill M; Cushing, Lara

    2013-01-01

    Objective: We examined the distribution of heat risk–related land cover (HRRLC) characteristics across racial/ethnic groups and degrees of residential segregation. Methods: Block group–level tree canopy and impervious surface estimates were derived from the 2001 National Land Cover Dataset for densely populated urban areas of the United States and Puerto Rico, and linked to demographic characteristics from the 2000 Census. Racial/ethnic groups in a given block group...

  8. 76 FR 23198 - Segregation of Lands-Renewable Energy

    Science.gov (United States)

    2011-04-26

    ..., or * * * this Executive Order.'' Exec. Order No. 12866, 58 FR 51738 (Oct. 4, 1993). Wind--Wind energy... Bureau of Land Management 43 CFR Parts 2090 and 2800 RIN 1004-AE19 Segregation of Lands--Renewable Energy... (202) 912-7350 for information relating to the BLM's renewable energy program or the substance of...

  9. 76 FR 23230 - Segregation of Lands-Renewable Energy

    Science.gov (United States)

    2011-04-26

    ....'' Exec. Order No. 12866, 58 FR 51738 (Oct. 4, 1993). Wind--Wind energy ROW site testing and development... Bureau of Land Management 43 CFR Parts 2090 and 2800 RIN 1004-AE19 Segregation of Lands--Renewable Energy... BLM's renewable energy program or the substance of the proposed rule, or Ian Senio at (202)...

  10. Gender segregation and wage gap: an East-West comparison

    Czech Academy of Sciences Publication Activity Database

    Jurajda, Štěpán

    Praha: CERGE-EI, 2011 - (Dušek, L.; Lízal, L.), s. 269-279 ISBN 978-80-7344-238-5 Institutional research plan: CEZ:AV0Z70850503 Keywords : gender segregation * wage differences * East-West comparison Subject RIV: AH - Economics http://www.cerge-ei.cz/pdf/books/cerge-ei-tackles-transition.pdf

  11. 9 CFR 117.5 - Segregation of animals.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Segregation of animals. 117.5 Section 117.5 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS ANIMALS AT...

  12. Segregating Schools: The Foreseeable Consequences of Tuition Tax Credits.

    Science.gov (United States)

    Yale Law Journal, 1979

    1979-01-01

    Argues that the effect of a proposed tuition tax credit is school segregation, creating serious constitutional objections under the due process clause. A voucher system would avoid these constitutional objections. Available from the Yale Law Journal, 401A Yale Station, New Haven, CT 06520. (Author/IRT)

  13. Visual texture segregation by the chimpanzee (Pan troglodytes).

    Science.gov (United States)

    Tomonaga, M

    1999-03-01

    One adult male chimpanzee (Pan troglodytes) was trained to detect a target area consisting of texture elements from the background texture made of the different elements from the target area. The subject was given eight different stimulus conditions. In Condition 1, segregation was based on the difference of local feature of elements but not on global similarity. Conditions 2-3 investigated the effects of the number of terminators, which was considered as 'textons' in human texture perception. The chimpanzee showed better performance when the discrimination can be based on the difference of the number of terminators. This tendency, however, was reversed when the local salient feature (length of shorter lines) was enhanced, as in Enns' [15] study with humans as subjects. The subject showed asymmetries in segregation performance when discriminating based on gap (Conditions 4-5), line length (Condition 6), and regularity of line arrangement (Condition 7). Observed asymmetries were consistent with humans and with visual search asymmetries. The performance of texture segregation by the chimpanzee was consistent with humans, and the texture segregation is one of the useful tasks for comparative study of early vision as well as visual search task. PMID:10512587

  14. Separate but Equal: Segregated Religious Education in Egypt's Public Schools

    Science.gov (United States)

    Isaac, John

    2012-01-01

    The Arab Spring exposed the hidden secrets of Egyptian society to the global community. In spite of the insatiable media attention paid to the Mubarak regime and the toll it took on the entire country, Egypt's education system received little attention. For decades, Egypt's public schools have forced students to attend segregated classes, based on…

  15. A mechanistic study of impurity segregation at silicon grain boundaries

    International Nuclear Information System (INIS)

    The segregation behavior of carbon and oxygen atoms at various silicon grain boundaries was studied using a combination of atomistic simulation and analytical modeling. First, quasi-lattice Grand Canonical Monte Carlo simulations were used to compute segregation isotherms as a function of grain boundary type, impurity atom loading level, and temperature. Next, the atomistic results were employed to regress different analytical segregation models and extract thermodynamic and structural properties. The multilayer Brunauer–Emmett–Teller (BET) isotherm was found to quantitatively capture all the simulation conditions probed in this work, while simpler, single layer models such as the Langmuir-McLean model did not. Some of the BET parameters, namely, the binding free energy of the first adsorption layer and the impurity holding capacity of each layer, were tested for correlation with various measures of grain boundary structure and/or mechanical properties. It was found that certain measures of the atomistic stress distribution correlate strongly with the first-layer binding free energy for substitutional carbon atoms, while common grain boundary identifiers such as sigma value and energy density are not useful in this regard. Preliminary analysis of the more complex case of interstitial oxygen segregation showed that similar measures based on atomistic stress also may be useful here, but more systematic correlative studies are needed to develop a comprehensive picture

  16. Factors shaping workplace segregation between natives and immigrants

    NARCIS (Netherlands)

    Strömgren, M.; Tammaru, T.; Danzer, A.M.; van Ham, M.; Marcinczak, S.; Stjernström, O.; Lindgren, U.

    2014-01-01

    Marie Curie programme under the European Union's Seventh Framework Programme (FP/2007-2013) / Career Integration Grant n. PCIG10-GA-2011-303728 (CIG Grant NBHCHOICE, Neighbourhood choice, neighbourhood sorting, and neighbourhood effects). Research on segregation of immigrant groups is increasingly

  17. New atom probe approaches to studying segregation in nanocrystalline materials

    Energy Technology Data Exchange (ETDEWEB)

    Samudrala, S.K.; Felfer, P.J.; Araullo-Peters, V.J. [School of Aerospace, Mechanical and Mechatronic Engineering, University of Sydney, NSW 2006 (Australia); The Australian Centre for Microscopy and Microanalysis, The University of Sydney, NSW 2006 (Australia); Cao, Y.; Liao, X.Z. [School of Aerospace, Mechanical and Mechatronic Engineering, University of Sydney, NSW 2006 (Australia); Cairney, J.M., E-mail: julie.cairney@sydney.edu.au [School of Aerospace, Mechanical and Mechatronic Engineering, University of Sydney, NSW 2006 (Australia); The Australian Centre for Microscopy and Microanalysis, The University of Sydney, NSW 2006 (Australia)

    2013-09-15

    Atom probe is a technique that is highly suited to the study of nanocrystalline materials. It can provide accurate atomic-scale information about the composition of grain boundaries in three dimensions. In this paper we have analysed the microstructure of a nanocrystalline super-duplex stainless steel prepared by high pressure torsion (HPT). Not all of the grain boundaries in this alloy display obvious segregation, making visualisation of the microstructure challenging. In addition, the grain boundaries present in the atom probe data acquired from this alloy have complex shapes that are curved at the scale of the dataset and the interfacial excess varies considerably over the boundaries, making the accurate characterisation of the distribution of solute challenging using existing analysis techniques. In this paper we present two new data treatment methods that allow the visualisation of boundaries with little or no segregation, the delineation of boundaries for further analysis and the quantitative analysis of Gibbsian interfacial excess at boundaries, including the capability of excess mapping. - Highlights: ► New data treatment methods allow delineation of grain boundaries, even without segregation. ► Proxigrams calculated from the surfaces accurately show the extent of segregation. ► Tessellation of the data volume can be used to map the Gibbsian interfacial excess.

  18. Bulk ordering and surface segregation in Ni50Pt50

    DEFF Research Database (Denmark)

    Pourovskii, L.P.; Ruban, Andrei; Abrikosov, I.A.;

    2001-01-01

    in the bulk compare well with experimental data. The surface-alloy compositions for the (111) and (110) facets above the ordering transition temperature are also found to be in a good agreement with experiments. It is demonstrated that the segregation profile at the (110) surface of NiPt is mainly caused...

  19. 49 CFR 177.848 - Segregation of hazardous materials.

    Science.gov (United States)

    2010-10-01

    ....848, see the List of CFR Sections Affected which appears in the Finding Aids section of the printed... 49 Transportation 2 2010-10-01 2010-10-01 false Segregation of hazardous materials. 177.848 Section 177.848 Transportation Other Regulations Relating to Transportation PIPELINE AND...

  20. Charter Schools and the Risk of Increased Segregation

    Science.gov (United States)

    Rotberg, Iris C.

    2014-01-01

    This article examines a wide array of research on the link between school choice programs and student segregation and draws implications for the Obama Administration's policy promoting the national expansion of charter schools. The research demonstrates how the proliferation of charter schools risks increasing current levels of segregation…

  1. Chromosome segregation errors: a double-edged sword

    NARCIS (Netherlands)

    Janssen, A.

    2012-01-01

    Unequal separation of the mother cells’ DNA over its two daughter cells upon cell division is a prevalent phenotype found in cancer cells. This imbalanced nuclear division manifests itself as chromosome segregation errors in the final phases of Mitosis. Chromosome unstable (CIN) cancer cells continu

  2. Effects of Groups’ Spatial Segregation on Processes of Opinion Polarization

    NARCIS (Netherlands)

    Feliciani, Thomas; Flache, Andreas

    2015-01-01

    We contribute to the literature about processes of opinion formation, investigating theoretically how the spatial segregation of two groups affects opinion polarization as a possible outcome of opinion formation. We focus on two processes of opinion polarization (negative influence and persuasive ar

  3. Kinetics of interstitial segregation in Cottrell atmospheres and grain boundaries

    Czech Academy of Sciences Publication Activity Database

    Svoboda, Jiří; Zickler, G. A.; Kozeschnik, E.; Fischer, F. D.

    2015-01-01

    Roč. 95, č. 9 (2015), s. 458-465. ISSN 0950-0839 R&D Projects: GA ČR(CZ) GA15-06390S Institutional support: RVO:68081723 Keywords : segregation * grain boundaries * dislocations * simulation * thermodynamic extremal principle Subject RIV: BJ - Thermodynamics Impact factor: 1.087, year: 2014

  4. Proximate drivers of spatial segregation in non-breeding albatrosses

    Science.gov (United States)

    Clay, Thomas A.; Manica, Andrea; Ryan, Peter G.; Silk, Janet R. D.; Croxall, John P.; Ireland, Louise; Phillips, Richard A.

    2016-01-01

    Many animals partition resources to avoid competition, and in colonially-breeding species this often leads to divergent space or habitat use. During the non-breeding season, foraging constraints are relaxed, yet the patterns and drivers of segregation both between and within populations are poorly understood. We modelled habitat preference to examine how extrinsic (habitat availability and intra-specific competition) and intrinsic factors (population, sex and breeding outcome) influence the distributions of non-breeding grey-headed albatrosses Thalassarche chrysostoma tracked from two major populations, South Georgia (Atlantic Ocean) and the Prince Edward Islands (Indian Ocean). Spatial segregation was greater than expected, reflecting distinct seasonal differences in habitat selection and accessibility, and avoidance of intra-specific competition with local breeders. Previously failed birds segregated spatially from successful birds during summer, when they used less productive waters, suggesting a link between breeding outcome and subsequent habitat selection. In contrast, we found weak evidence of sexual segregation, which did not reflect a difference in habitat use. Our results indicate that the large-scale spatial structuring of albatross distributions results from interactions between extrinsic and intrinsic factors, with important implications for population dynamics. As habitat preferences differed substantially between colonies, populations should be considered independently when identifying critical areas for protection. PMID:27443877

  5. Gender Segregation in the Employment of Higher Education Graduates

    Science.gov (United States)

    Vuorinen-Lampila, Päivi

    2016-01-01

    This article examines the employment and placement in the working life of Finnish higher education graduates (i.e. graduates from universities and polytechnics), focusing on gender equality. It reports a study on gender segregation in higher education and working life, considered in relation to Nordic gender equality policies. The data were…

  6. Theories of Occupational Segregation by Sex: An Overview.

    Science.gov (United States)

    Anker, Richard

    1997-01-01

    Reviews theoretical explanations for gender segregation in occupations: neoclassical, human capital, institutional and labor market segmentation, and gender discrimination. Determines that gender discrimination theories are most compelling, given the enormous overlap in abilities and preferences of individual men and women. (SK)

  7. Urban Education and Segregation: The Responses from Young People

    Science.gov (United States)

    Ohrn, Elisabet

    2012-01-01

    This article takes as a starting point the segregation of urban areas and discusses schooling in the neighbourhoods typically associated with problems and challenges, in order to explore young people's responses to their schooling and social positions. Such responses include individual acts, such as rejecting further schooling or dismissing the…

  8. Gender segregation and wage gap: an East-West comparison

    Czech Academy of Sciences Publication Activity Database

    Jurajda, Štěpán

    2005-01-01

    Roč. 3, 2-3 (2005), s. 598-607. ISSN 1542-4766 R&D Projects: GA ČR GA403/03/0340 Institutional research plan: CEZ:AV0Z70850503 Keywords : gender segregation * wage differences * East-West comparison Subject RIV: AH - Economics http://www.jstor.org/stable/40005002

  9. Dynamics of Escherichia coli Chromosome Segregation during Multifork Replication

    DEFF Research Database (Denmark)

    Nielsen, Henrik Jørck; Youngren, Brenda; Hansen, Flemming G.;

    2007-01-01

    Slowly growing Escherichia coli cells have a simple cell cycle, with replication and progressive segregation of the chromosome completed before cell division. In rapidly growing cells, initiation of replication occurs before the previous replication rounds are complete. At cell division, the...

  10. Towards understanding the molecular basis of bacterial DNA segregation

    DEFF Research Database (Denmark)

    Leonard, Thomas A.; Møller-Jensen, Jakob; Löwe, Jan

    2005-01-01

    poles and, significantly, the emergence of mitotic-like machineries capable of segregating plasmid DNA. We further describe surprising similarities between proteins involved in DNA partitioning (ParA/ParB) and control of cell division (MinD/MinE), suggesting a mechanism for intracellular positioning...

  11. New atom probe approaches to studying segregation in nanocrystalline materials

    International Nuclear Information System (INIS)

    Atom probe is a technique that is highly suited to the study of nanocrystalline materials. It can provide accurate atomic-scale information about the composition of grain boundaries in three dimensions. In this paper we have analysed the microstructure of a nanocrystalline super-duplex stainless steel prepared by high pressure torsion (HPT). Not all of the grain boundaries in this alloy display obvious segregation, making visualisation of the microstructure challenging. In addition, the grain boundaries present in the atom probe data acquired from this alloy have complex shapes that are curved at the scale of the dataset and the interfacial excess varies considerably over the boundaries, making the accurate characterisation of the distribution of solute challenging using existing analysis techniques. In this paper we present two new data treatment methods that allow the visualisation of boundaries with little or no segregation, the delineation of boundaries for further analysis and the quantitative analysis of Gibbsian interfacial excess at boundaries, including the capability of excess mapping. - Highlights: ► New data treatment methods allow delineation of grain boundaries, even without segregation. ► Proxigrams calculated from the surfaces accurately show the extent of segregation. ► Tessellation of the data volume can be used to map the Gibbsian interfacial excess

  12. Interstitial and substitutional solute segregation at individual grain boundaries of α-iron: data revisited

    International Nuclear Information System (INIS)

    Theoretical calculations (usually density-functional-theory methods performed at 0 K) confirm the formerly assumed substitutional phosphorus segregation in α-iron. In contrast, the enthalpy–entropy compensation effect predicts that phosphorus should segregate interstitially. To resolve this discrepancy, we recalculated the values of the segregation enthalpy and entropy for the interstitial segregation of phosphorus according to the Guttmann model of segregation in multicomponent systems. This recalculation is based on earlier measured experimental data and shows that only slight changes in the values of the standard enthalpy and entropy of phosphorus, carbon and silicon segregation are obtained. Consequently, all dependences constructed previously remain qualitatively the same. By thermodynamic considerations based on the enthalpy–entropy compensation effect we quantitatively show that there is an alteration of the position of phosphorus at grain boundaries in α-Fe with increasing temperature: while substitutional segregation is preferred at 0 K, interstitial segregation occurs at temperatures of practical interest. (paper)

  13. Measures of social segregation in the context of Warsaw, Berlin and Paris metropolitan areas

    Directory of Open Access Journals (Sweden)

    Grzegorczyk Anna

    2015-09-01

    Full Text Available Social segregation is a subject common in contemporary studies of metropolitan areas. Until recently, studies of segregation focused on the distribution of ethnic groups, immigrants, and the poor. Today, they also cover additional indicators such as demographic properties, education, and affiliation with social and professional categories, which can also serve to determine the causes of the segregation (including the self-segregation of the rich. This article aims to point out the measures of segregation that present the segregation levels in the most complete manner, along with their application in the context of three European metropolitan areas: Warsaw, Berlin, and Paris. The first part of the article is a review of the existing approaches to segregation measures, followed by the selection of research method, presentation of the analysis’ results, and evaluation of the applied methods; presenting the opportunities and limitations in research of the social segregation phenomenon.

  14. Research on segregation evaluation methods of asphalt pavement based on air voids distribution

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Eye observation was used to evaluate the segregation degree of asphalt pavement, which was not much creditable. To the asphalt pavement, road surface texture measuring method which has appeared recently can identify gradational segregation; but it can't reflect the influence of the temperature segregation. However,using infrared temperature detector to evaluate the segregation must be taken during paving, which brings much inconvenience. In this paper, measuring the air voids distribution using non-nuclear density gauge to evaluate asphalt pavement segregation was introduced. Result shows that this method can directly reflect the comprehensive results of the two types of segregation in a high efficient and accurate way. Moreover, using the sketch map of segregation area can help to analyze the segregation reason visually.

  15. Convection and segregation in fluidised granular systems exposed to two-dimensional vibration

    Science.gov (United States)

    Windows-Yule, C. R. K.

    2016-03-01

    Convection and segregation in granular systems not only provide a rich phenomenology of scientifically interesting behaviours but are also crucial to numerous ‘real-world’ processes ranging from important and widely used industrial procedures to potentially cataclysmic geophysical phenomena. Simple, small-scale experimental or simulated test systems are often employed by researchers in order to gain an understanding of the fundamental physics underlying the behaviours of granular media. Such systems have been the subject of extensive research over several decades, with numerous system geometries and manners of producing excitation explored. Energy is commonly provided to granular assemblies through the application of vibration—the simplicity of the dynamical systems produced and the high degree of control afforded over their behaviour make vibrated granular beds a valuable canonical system by which to explore a diverse range of phenomena. Although a wide variety of vibrated systems have been explored in the existing literature, the vast majority are exposed to vibration along only a single spatial direction. In this paper, we study highly fluidised systems subjected to strong, multi-directional driving, providing a first insight into the dynamics and behaviours of these systems which may potentially hold valuable new information relevant to important industrial and natural processes. With a particular focus on the processes of convection and segregation, we analyse the various states and phase transitions exhibited by our system, detailing a number of previously unobserved dynamical phenomena and system states.

  16. Stress partition and microstructure in size-segregating granular flows.

    Science.gov (United States)

    Staron, L; Phillips, J C

    2015-08-01

    When a granular mixture involving grains of different sizes is shaken, sheared, mixed, or left to flow, grains tend to separate by sizes in a process known as size segregation. In this study, we explore the size segregation mechanism in granular chute flows in terms of the pressure distribution and granular microstructure. Therefore, two-dimensional discrete numerical simulations of bidisperse granular chute flows are systematically analyzed. Based on the theoretical models of J. M. N. T. Gray and A. R. Thornton [Proc. R. Soc. A 461, 1447] and K. M. Hill and D. S. Tan [J. Fluid Mech. 756, 54 (2014)], we explore the stress partition in the phases of small and large grains, discriminating between contact stresses and kinetic stresses. Our results support both gravity-induced and shear-gradient-induced segregation mechanisms. However, we show that the contact stress partition is extremely sensitive to the definition of the partial stress tensors and, more specifically, to the way mixed contacts (i.e., involving a small grain and a large grain) are handled, making conclusions on gravity-induced segregation uncertain. By contrast, the computation of the partial kinetic stress tensors is robust. The kinetic pressure partition exhibits a deviation from continuum mixture theory of a significantly higher amplitude than the contact pressure and displays a clear dependence on the flow dynamics. Finally, using a simple approximation for the contact partial stress tensors, we investigate how the contact stress partition relates to the flow microstructure and suggest that the latter may provide an interesting proxy for studying gravity-induced segregation. PMID:26382397

  17. Stress partition and microstructure in size-segregating granular flows

    Science.gov (United States)

    Staron, L.; Phillips, J. C.

    2015-08-01

    When a granular mixture involving grains of different sizes is shaken, sheared, mixed, or left to flow, grains tend to separate by sizes in a process known as size segregation. In this study, we explore the size segregation mechanism in granular chute flows in terms of the pressure distribution and granular microstructure. Therefore, two-dimensional discrete numerical simulations of bidisperse granular chute flows are systematically analyzed. Based on the theoretical models of J. M. N. T. Gray and A. R. Thornton [Proc. R. Soc. A 461, 1447 (2005), 10.1098/rspa.2004.1420] and K. M. Hill and D. S. Tan [J. Fluid Mech. 756, 54 (2014), 10.1017/jfm.2014.271], we explore the stress partition in the phases of small and large grains, discriminating between contact stresses and kinetic stresses. Our results support both gravity-induced and shear-gradient-induced segregation mechanisms. However, we show that the contact stress partition is extremely sensitive to the definition of the partial stress tensors and, more specifically, to the way mixed contacts (i.e., involving a small grain and a large grain) are handled, making conclusions on gravity-induced segregation uncertain. By contrast, the computation of the partial kinetic stress tensors is robust. The kinetic pressure partition exhibits a deviation from continuum mixture theory of a significantly higher amplitude than the contact pressure and displays a clear dependence on the flow dynamics. Finally, using a simple approximation for the contact partial stress tensors, we investigate how the contact stress partition relates to the flow microstructure and suggest that the latter may provide an interesting proxy for studying gravity-induced segregation.

  18. Whole-exome sequencing of a pedigree segregating asthma

    Directory of Open Access Journals (Sweden)

    DeWan Andrew T

    2012-10-01

    Full Text Available Abstract Background Despite the success of genome-wide association studies for asthma, few, if any, definitively causal variants have been identified and there is still a substantial portion of the heritability of the disease yet to be discovered. Some of this “missing heritability” may be accounted for by family-specific coding variants found to be segregating with asthma. Methods To identify family-specific variants segregating with asthma, we recruited one family from a previous study of asthma as reporting multiple asthmatic and non-asthmatic children. We performed whole-exome sequencing on all four children and both parents and identified coding variants segregating with asthma that were not found in other variant databases. Results Ten novel variants were identified that were found in the two affected offspring and affected mother, but absent in the unaffected father and two unaffected offspring. Of these ten, variants in three genes (PDE4DIP, CBLB, and KALRN were deemed of particular interest based on their functional prediction scores and previously reported function or asthma association. We did not identify any common risk variants segregating with asthma, however, we did observe an increase in the number of novel, nonsynonymous variants in asthma candidate genes in the asthmatic children compared to the non-asthmatic children. Conclusions This is the first report applying exome sequencing to identify asthma susceptibility variants. Despite having sequenced only one family segregating asthma, we have identified several potentially functional variants in interesting asthma candidate genes. This will provide the basis for future work in which more families will be sequenced to identify variants across families that cluster within genes.

  19. Competition of Brazil nut effect, buoyancy, and inelasticity induced segregation in a granular mixture

    OpenAIRE

    Brito López, Ricardo; Soto, R.

    2009-01-01

    It has been recently reported that a granular mixture in which grains differ in their restitution coefficients presents segregation: the more inelastic particles sink to the bottom. When other segregation mechanisms as buoyancy and the Brazil nut effect are present, the inelasticity induced segregation can compete with them. First, a detailed analysis, based on numerical simulations of two dimensional systems, of the competition between buoyancy and the inelasticity induced segregation is pre...

  20. Measures of social segregation in the context of Warsaw, Berlin and Paris metropolitan areas

    OpenAIRE

    Grzegorczyk Anna; Jaczewska Barbara

    2015-01-01

    Social segregation is a subject common in contemporary studies of metropolitan areas. Until recently, studies of segregation focused on the distribution of ethnic groups, immigrants, and the poor. Today, they also cover additional indicators such as demographic properties, education, and affiliation with social and professional categories, which can also serve to determine the causes of the segregation (including the self-segregation of the rich). This article aims to point out the measures o...

  1. csi2p modulates microtubule dynamics and organizes the bipolar spindle for chromosome segregation

    OpenAIRE

    Costa, Judite; Fu, Chuanhai; Khare, V. Mohini; Tran, Phong T.

    2014-01-01

    Proper chromosome segregation is of paramount importance for proper genetic inheritance. Defects in chromosome segregation can lead to aneuploidy, which is a hallmark of cancer cells. Eukaryotic chromosome segregation is accomplished by the bipolar spindle. Additional mechanisms, such as the spindle assembly checkpoint and centromere positioning, further help to ensure complete segregation fidelity. Here we present the fission yeast csi2 +. csi2p localizes to the spindle poles, where it regul...

  2. The Impact of Social Exclusion in Residential Segregation: A gipsy Neighbourhood Fevzi Pasa in Turkey

    OpenAIRE

    GÜLTEKİN, Nevin

    2010-01-01

    In this article, residential segregation of a gypsy group is analyzed as ethnicity-based and in relation to social segregation (through the Canakkale - Fevzi Pasa Gypsy Neighborhood). The aim of this analysis is to define the conditions under which and areas in which this type of segregation provides (dis)advantages. As a result, residential segregation can be explained through three basic reasons as external factors and obligations, internal factors and willingness, and the circular interact...

  3. Undocumented Migration and the Residential Segregation of Mexicans in New Destinations1

    OpenAIRE

    Hall, Matthew; Stringfield, Jonathan

    2014-01-01

    This study uses data from the 2000 Census and 2005–2009 American Community Survey to examine the impact of undocumented Mexican migration to new destinations on residential segregation between Mexican immigrants and native-born whites and native-born blacks. We find that Mexican-white and Mexican-black segregation is higher in new Mexican gateways than in established areas and that, for Mexican-immigrant segregation from whites, this heightened level of residential segregation in new destinat...

  4. Association of Residential Segregation and Disability: A Multilevel Study Using Iranian Census Data

    OpenAIRE

    Hashemi Nazari, Seyed Saeed; Mahmoodi, Mahmood; Mansournia, Mohammad-Ali; Holakouie Naieni, Kourosh

    2012-01-01

    The association of racial segregation and health outcomes has been reviewed recently in the literature, but the health effect of other contexts of segregation with respect to residential environment has not as yet been fully reviewed. Besides, most of the literature on segregation has been performed in Western countries. Here, we undertake a multilevel analysis of residential segregation of socioeconomic and demographic factors and disability rate in an Eastern developing country in order to ...

  5. Capturing the two dimensions of residential segregation at the neighborhood level for health research

    OpenAIRE

    Oka, Masayoshi; Wong, David W. S.

    2014-01-01

    Two conceptual and methodological foundations of segregation studies are that (i) segregation involves more than one group, and (ii) segregation measures need to quantify how different population groups are distributed across space. Therefore, percentage of population belonging to a group is not an appropriate measure of segregation because it does not describe how populations are spread across different areal units or neighborhoods. In principle, evenness and isolation are the two distinct d...

  6. Residential Segregation and Infant Mortality: A Multilevel Study Using Iranian Census Data

    OpenAIRE

    MA Mansournia; Mahmoodi, M; SS Hashemi Nazari; K Holakouie Naieni

    2012-01-01

    Background There is a great amount of literature concerning the effect of racial segregation on health outcomes but few papers have discussed the effect of segregation on the basis of social, demographic and economic characteristics on health. We estimated the independent effect of segregation of determinants of socioeconomic status on infant mortality in Iranian population. Methods: For measuring segregation, we used generalized dissimilarity index for two group and multi group nominal varia...

  7. Learning Apart, Living Apart: How the Racial and Ethnic Segregation of Schools and Colleges Perpetuates Residential Segregation

    Science.gov (United States)

    Goldsmith, Pat Rubio

    2010-01-01

    Background: Despite a powerful civil rights movement and legislation barring discrimination in housing markets, residential neighborhoods remain racially segregated. Purpose: This study examines the extent to which neighborhoods' racial composition is inherited across generations and the extent to which high schools' and colleges' racial…

  8. The Complex Determinants of School Intake Characteristics and Segregation, England 1989 to 2014

    Science.gov (United States)

    Gorard, Stephen

    2016-01-01

    The extent of between-school segregation, or clustering of disadvantaged students within schools, in England varies depending on the indicator of interest. For example, the trend over time for segregation by student poverty differs from those for ethnicity or special educational need. Additionally the causes of the level of segregation for any…

  9. 78 FR 58555 - Notice of Segregation of Public Lands for the Proposed Stateline Solar Farm, CA

    Science.gov (United States)

    2013-09-24

    ... notice in the Federal Register on August 4, 2011 (76 FR 47235) to segregate the lands described above for... Bureau of Land Management Notice of Segregation of Public Lands for the Proposed Stateline Solar Farm, CA... the Materials Act of 1947. The segregation is needed to continue processing the proposed...

  10. 28 CFR 540.16 - Inmate correspondence while in segregation and holdover status.

    Science.gov (United States)

    2010-07-01

    ... segregation and holdover status. 540.16 Section 540.16 Judicial Administration BUREAU OF PRISONS, DEPARTMENT... Inmate correspondence while in segregation and holdover status. (a) The Warden shall permit an inmate in... those of other inmates insofar as practical. (b) The Warden shall permit an inmate in segregation...

  11. Influence of mechanical properties on mixing and segregation of granular material

    OpenAIRE

    Dziugys, A.; Navakas, R.

    2007-01-01

    Processes of mixing and segregation in a packed bed of granular material stirred by a periodically moving rectangular bar are simulated by the discrete element method (DEM). Influence of mechanical properties of the particle material (dynamic friction coefficient, density, elastic modulus) on the segregation intensity is researched. Dynamic friction coefficient was found to have the most noticeable influence to the segregation intensity.

  12. 49 CFR 176.140 - Segregation from other classes of hazardous materials.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Segregation from other classes of hazardous... CARRIAGE BY VESSEL Detailed Requirements for Class 1 (Explosive) Materials Segregation § 176.140 Segregation from other classes of hazardous materials. (a) Class 1 (explosive) materials must be...

  13. New perspectives on ethnic segregation over time and space: A domains approach

    NARCIS (Netherlands)

    Van Ham, M.; Tammaru, T.

    2016-01-01

    The term segregation has a strong connotation with residential neighbourhoods, and most studies investigating ethnic segregation focus on the urban mosaic of ethnic concentrations in residential neighbourhoods. However, there is now a small, but growing, literature, which focusses on segregation in

  14. Neighborhood Residential Segregation and Physical Health among Hispanic Americans: Good, Bad, or Benign?

    Science.gov (United States)

    Lee, Min-Ah; Ferraro, Kenneth F.

    2007-01-01

    Although considerable evidence shows that residential segregation is deleterious to the health of African Americans, findings regarding segregation and health for Hispanic Americans are inconsistent. Competing hypotheses regarding the effects of neighborhood segregation on health are tested with data from Puerto Rican and Mexican American…

  15. The Effect of World War I on Black Occupational and Residential Segregation: The Case of Pittsburgh.

    Science.gov (United States)

    Darden, Joe T.

    1988-01-01

    Study of census figures for Pittsburgh between 1900 and 1920 reveals that World War I had only a small measurable effect on reducing occupational segregation of Black men and White men and residential segregation by race. The war had no effect on reducing occupational segregation of Black women and White women. (BJV)

  16. Residential segregation and public policies: São Paulo in the 1990's

    OpenAIRE

    Haroldo da Gama Torres; Ana Maura Tomesani

    2006-01-01

    The article aims at assessing the evolution of residential segregation in the metropolitan area of São Paulo, Brazil, in the 1990's, which saw a significant increase of socioeconomic segregation. In addition to interpreting the phenomenon, the article proposes a discussion on the reasons the residential segregation should be considered a fundamental issue for the formulation of social urban policies.

  17. Relationship between School and Residential Segregation at the Turn of the Century.

    Science.gov (United States)

    Rickles, Jordan; Ong, Paul M.

    This paper examines the relationship between school and residential segregation, noting that while these two forms of segregation are fundamentally linked, other factors cause them to diverge. The analysis focuses on segregation in 329 metropolitan areas. Data come from the 1998-99 National Center for Education Statistics Common Core of Data…

  18. Trends in the Residential Segregation of Blacks, Hispanics, and Asians: 1970-1980.

    Science.gov (United States)

    Massey, Douglas S.; Denton, Nancy A.

    1987-01-01

    Examines trends in residential segregation for Blacks, Hispanics, and Asians in 60 Standard Metropolitan Statistical Areas (SMSAs) between 1970 and 1980. Black-Anglo segregation remained high in the North, but decreased in some smaller Southern and Western SMSAs. Hispanic segregation was markedly below that of Blacks, but has increased. Asian…

  19. New perspectives on ethnic segregation over time and space: A domains approach

    NARCIS (Netherlands)

    Van Ham, M.; Tammaru, T.

    2016-01-01

    Ethnic segregation has most often been studied at the place of residence, segregation being defined on the basis of the relative presence of different groups within city neighbourhoods. It is increasingly recognized, however, that segregation occurs in different ways in different domains (such as th

  20. Freedom from Racial Barriers: The Empirical Evidence on Vouchers and Segregation. School Choice Issues in Depth

    Science.gov (United States)

    Forster, Greg

    2006-01-01

    This report collects the results of all available studies using valid empirical methods to compare segregation in public and private schools, both in general and in the context of school voucher programs. Examining the widespread claims that private schools have high segregation levels and vouchers will lead to greater segregation, this report…

  1. Segregating gas from melt: an experimental study of the Ostwald ripening of vapor bubbles in magmas

    Science.gov (United States)

    Lautze, Nicole C.; Sisson, Thomas W.; Mangan, Margaret T.; Grove, Timothy L.

    2011-01-01

    Diffusive coarsening (Ostwald ripening) of H2O and H2O-CO2 bubbles in rhyolite and basaltic andesite melts was studied with elevated temperature–pressure experiments to investigate the rates and time spans over which vapor bubbles may enlarge and attain sufficient buoyancy to segregate in magmatic systems. Bubble growth and segregation are also considered in terms of classical steady-state and transient (non-steady-state) ripening theory. Experimental results are consistent with diffusive coarsening as the dominant mechanism of bubble growth. Ripening is faster in experiments saturated with pure H2O than in those with a CO2-rich mixed vapor probably due to faster diffusion of H2O than CO2 through the melt. None of the experimental series followed the time1/3 increase in mean bubble radius and time-1 decrease in bubble number density predicted by classical steady-state ripening theory. Instead, products are interpreted as resulting from transient regime ripening. Application of transient regime theory suggests that bubbly magmas may require from days to 100 years to reach steady-state ripening conditions. Experimental results, as well as theory for steady-state ripening of bubbles that are immobile or undergoing buoyant ascent, indicate that diffusive coarsening efficiently eliminates micron-sized bubbles and would produce mm-sized bubbles in 102–104 years in crustal magma bodies. Once bubbles attain mm-sizes, their calculated ascent rates are sufficient that they could transit multiple kilometers over hundreds to thousands of years through mafic and silicic melt, respectively. These results show that diffusive coarsening can facilitate transfer of volatiles through, and from, magmatic systems by creating bubbles sufficiently large for rapid ascent.

  2. Integration versus segregation: ethnic minorities and urban politics in Singapore.

    Science.gov (United States)

    Van Grunsven, L

    1992-01-01

    The population of Singapore is very heterogenous. The main groups distinguished are the Chinese, the Malays, the Indians, and others. Since the end of the 1950s these groups have remained stable: Chinese make up 76%, Malays 15%, Indians 6%, and others 3% of the total population. In the mid-1960s almost 25% of the Chinese were working in commerce as opposed to only 10% of the Malays. More than 50% of Malays held low-paying jobs in services compared to less than 30% of the Chinese. The backward position of the Malays during the 1960s was reinforced by residential location in the peripheries. In the 1950s and 1960s the city center was exclusively inhabited by the Chinese. Malays were living in small clusters across the city and in 1 large cluster in the eastern part of the city. The ruling People's Action Party government during the 1960s adopted the New Economic Policy which granted economic and social privileges to the Malays. In 1969 the decision was made to disperse the Malay community across the city. In the early 1960s the state launched a large-scale public housing program through the newly created Housing and Development Board (H.D.B.). Between 1970 and 1982 Malay households living in H.D.B. apartments increased from 23% to 77%. Between 1970 and 1980 substantial declustering of the malay community and desegregation of the ethnic groups had occurred. In 24 areas out of 51 subdivisions of Singapore the Malay quotient decreased between 1970 and 1980. In 1980 the location quotient for Malay settlement areas was significantly lower (varying between 0.07 and 2.18) than the highest quotient in 1970 (varying between 0.06 and 3.7). During the 1980s the economic participation of the Malays increased steadily, they became gradually incorporated into industry, and increasingly moved upward within the public housing sector. Between 1980 and 1990 the Malay households living in H.D.B. dwellings increased from 72% to 97%. Notwithstanding residential integration, ethnic

  3. White Residential Segregation in U.S. Metropolitan Areas: Conceptual Issues, Patterns, and Trends from the US Census, 1980 to 2010.

    Science.gov (United States)

    Iceland, John; Sharp, Gregory

    2013-10-01

    Racial and ethnic diversity continues to spread to communities across the United States. Rather than focus on the residential patterns of specific minority or immigrant groups, this study examines changing patterns of white residential segregation in metropolitan America. Using data from the 1980 to 2010 decennial censuses, we calculate levels of white segregation using two common measures, analyze the effect of defining the white population in different ways, and, drawing upon the group threat theoretical perspective, we examine the metropolitan correlates of white segregation. We find that white segregation from others declined significantly from 1980 to 2010, regardless of the measure of segregation or the white population used. However, we find some evidence consistent with the group threat perspective, as white dissimilarity is higher in metro areas that are more diverse, and especially those with larger black populations. Nevertheless, our findings indicate that whites having been living in increasingly integrated neighborhoods over the last few decades, suggesting some easing of the historical color line. PMID:24187411

  4. A sampling algorithm for segregation analysis

    Directory of Open Access Journals (Sweden)

    Henshall John

    2001-11-01

    Full Text Available Abstract Methods for detecting Quantitative Trait Loci (QTL without markers have generally used iterative peeling algorithms for determining genotype probabilities. These algorithms have considerable shortcomings in complex pedigrees. A Monte Carlo Markov chain (MCMC method which samples the pedigree of the whole population jointly is described. Simultaneous sampling of the pedigree was achieved by sampling descent graphs using the Metropolis-Hastings algorithm. A descent graph describes the inheritance state of each allele and provides pedigrees guaranteed to be consistent with Mendelian sampling. Sampling descent graphs overcomes most, if not all, of the limitations incurred by iterative peeling algorithms. The algorithm was able to find the QTL in most of the simulated populations. However, when the QTL was not modeled or found then its effect was ascribed to the polygenic component. No QTL were detected when they were not simulated.

  5. Monogenic Segregations in Backcross Progenies of Capsicum baccatumx Two Interspecific F1 Hybrids and Some Possible Explanations for Distorted Segregation Ratios in Capsicum

    OpenAIRE

    Ahmet Naci ONUS

    2000-01-01

    Monogenic segregations of certain morphological and isozymic characters were studied in backcross progenies of Capsicum baccatumL. ( Solanaceae) x two interspecific F1 hybrids and distorted segregation ratios were noted. It was observed that isozyme markers Est-5, Idh-1, Pgm-2, and Pgi-2, and morphological marker gene P for fruit persistence showed distorted segregation ratios in the first backcross generation of both C. baccatumHawkes 6489 (P.G.Smith) x F1 ( C. baccatum Hawkes 6489 x Capsi...

  6. Molecular dynamics simulation of amorphous segregation inAg-Rh alloys

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jingxiang; BIAN Xiufang

    2003-01-01

    Molecular dynamics simulation was carried out to investigate the liquid and amorphous microstructures of binary Agx-Rh(100-x) (x = 25, 50, 75 in atom fraction) alloys. Segregation feature of homogeneous interatomic binding of Ag-Rh liquid was found and probed, which can be retained into amorphous solids upon rapid cooling. Homogeneous binding may occur when the difference in the elemental atomic sizes is less than 10%. The icosahedra in liquid before the formation of amorphous state exist in a stable state and the network formed by 1551-clusters in molten alloys would inhibit the crystallization and diffusion of atoms. A higher degree of 155 1-clusters will be favorable to form metallic glasses.

  7. Phosphorus segregation behavior at the grain boundary in a Ti-IF steel after annealing

    International Nuclear Information System (INIS)

    The behavior of phosphorus grain boundary segregation is researched for an interstitial-free Ti steel which is cold rolled and recrystallized by annealing for different times at 810 oC. The results show that the segregation of phosphorus at the grain boundary is a non-equilibrium phenomenon. The critical segregation time is 120 s, when the segregation level is about 14 at.%. Its segregation mechanism is a solute atom 'atmosphere' that is formed around each dislocation and moves toward grain boundary.

  8. Effect of Interstitial Media on Segregation in Vertically Vibrated Granular Mixtures

    International Nuclear Information System (INIS)

    Vertically vibrated segregation behaviors of binary granular mixtures with different interstitial media are experimentally investigated. To study the role of interstitial media on the segregation, two types of interstitial fluids are adopted and the resulting phase diagrams are compared. The water-immersed granular mixture exhibits two kinds of complete segregation behaviors: Brazil nut effect and sandwich patterns, at least the latter is absent in the same air-immersed mixture. Additionally, the segregation extent is improved remarkably for the water-immersed mixture. The experimental observation further confirms that the effect of interstitial media on the relative motion of grains is one of the predominant mechanisms for granular segregation

  9. An analogue model of melt segregation and accumulation processes in the Earth’s crust

    Directory of Open Access Journals (Sweden)

    Soesoo, Alvar

    2007-03-01

    Full Text Available An analogue experiment was carried out to model melt segregation from the solid rock matrix and its subsequent transport. Carbon dioxide gas and sand were used as analogue materials of crustal partial melt and host rock, respectively. The analogue model displays the diffusional transport mode at low flux rates and the transition to the ballistical mode as the response of the system to a higher gas flux. The ballistical mode is characterized by discontinuous transport and extraction of the gas phase in separate batches, which leads to the development of power law batch size distribution in the system. The gas is extracted preferentially in large batches and does not influence the state of the system and size distribution of remaining batches. The implications of the analogue model to real magmatic processes are supported by power law leucosome width distributions measured in several migmatite localities. The emergence of fractality and 1/f power spectrum of system fluctuations provide evidence of possible self-organized critical nature of melt segregation processes.

  10. Development of a robust modeling tool for radiation-induced segregation in austenitic stainless steels

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Ying [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Field, Kevin G [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Allen, Todd R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Busby, Jeremy T [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-09-01

    Irradiation-assisted stress corrosion cracking (IASCC) of austenitic stainless steels in Light Water Reactor (LWR) components has been linked to changes in grain boundary composition due to irradiation induced segregation (RIS). This work developed a robust RIS modeling tool to account for thermodynamics and kinetics of the atom and defect transportation under combined thermal and radiation conditions. The diffusion flux equations were based on the Perks model formulated through the linear theory of the thermodynamics of irreversible processes. Both cross and non-cross phenomenological diffusion coefficients in the flux equations were considered and correlated to tracer diffusion coefficients through Manning’s relation. The preferential atomvacancy coupling was described by the mobility model, whereas the preferential atom-interstitial coupling was described by the interstitial binding model. The composition dependence of the thermodynamic factor was modeled using the CALPHAD approach. Detailed analysis on the diffusion fluxes near and at grain boundaries of irradiated austenitic stainless steels suggested the dominant diffusion mechanism for chromium and iron is via vacancy, while that for nickel can swing from the vacancy to the interstitial dominant mechanism. The diffusion flux in the vicinity of a grain boundary was found to be greatly influenced by the composition gradient formed from the transient state, leading to the oscillatory behavior of alloy compositions in this region. This work confirms that both vacancy and interstitial diffusion, and segregation itself, have important roles in determining the microchemistry of Fe, Cr, and Ni at irradiated grain boundaries in austenitic stainless steels.

  11. Solute segregation kinetics and dislocation depinning in a binary alloy

    Science.gov (United States)

    Dontsova, E.; Rottler, J.; Sinclair, C. W.

    2015-06-01

    Static strain aging, a phenomenon caused by diffusion of solute atoms to dislocations, is an important contributor to the strength of substitutional alloys. Accurate modeling of this complex process requires both atomic spatial resolution and diffusional time scales, which is very challenging to achieve with commonly used atomistic computational methods. In this paper, we use the recently developed "diffusive molecular dynamics" (DMD) method that is capable of describing the kinetics of the solute segregation process at the atomic level while operating on diffusive time scales in a computationally efficient way. We study static strain aging in the Al-Mg system and calculate the depinning shear stress between edge and screw dislocations and their solute atmospheres formed for various waiting times with different solute content and for a range of temperatures. A simple phenomenological model is also proposed that describes the observed behavior of the critical shear stress as a function of segregation level.

  12. Investigation of boron segregation in low carbon steel

    Directory of Open Access Journals (Sweden)

    J. Lis

    2011-04-01

    Full Text Available Traces of born in the range 0,002-0,009 % are usually added to many grades of steel. The effect of boron on phase transformations and hardenability of low carbon low alloy steels depends on the form of its behavior in solid solution either in segregations or in precipitations. Temperature and cooling rate determine the existence of boron segregations on grain boundaries. In present paper simulations of boron concentrations were calculated with computer programme DICTRA for low carbon 0,08 %C steel with 0,006 % boron. Investigations were carried out for temperature 1300 – 700°C and cooling rates from 1°C/s to 100°C/s. The changes of boron concentrations in austenite and ferrite after commencement of γ→α phase transformation were established.

  13. Measuring geographic segregation: a graph-based approach

    Science.gov (United States)

    Hong, Seong-Yun; Sadahiro, Yukio

    2014-04-01

    Residential segregation is a multidimensional phenomenon that encompasses several conceptually distinct aspects of geographical separation between populations. While various indices have been developed as a response to different definitions of segregation, the reliance on such single-figure indices could oversimplify the complex, multidimensional phenomena. In this regard, this paper suggests an alternative graph-based approach that provides more detailed information than simple indices: The concentration profile graphically conveys information about how evenly a population group is distributed over the study region, and the spatial proximity profile depicts the degree of clustering across different threshold levels. These graphs can also be summarized into single numbers for comparative purposes, but the interpretation can be more accurate by inspecting the additional information. To demonstrate the use of these methods, the residential patterns of three major ethnic groups in Auckland, namely Māori, Pacific peoples, and Asians, are examined using the 2006 census data.

  14. Spillover-mediated feedforward-inhibition functionally segregates interneuron activity

    Science.gov (United States)

    Coddington, Luke T.; Rudolph, Stephanie; Lune, Patrick Vande; Overstreet-Wadiche, Linda; Wadiche, Jacques I.

    2013-01-01

    Summary Neurotransmitter spillover represents a form of neural transmission not restricted to morphologically defined synaptic connections. Communication between climbing fibers (CFs) and molecular layer interneurons (MLIs) in the cerebellum is mediated exclusively by glutamate spillover. Here, we show how CF stimulation functionally segregates MLIs based on their location relative to glutamate release. Excitation of MLIs that reside within the domain of spillover diffusion coordinates inhibition of MLIs outside the diffusion limit. CF excitation of MLIs is dependent on extrasynaptic NMDA receptors that enhance the spatial and temporal spread of CF signaling. Activity mediated by functionally segregated MLIs converges onto neighboring Purkinje cells (PCs) to generate a long-lasting biphasic change in inhibition. These data demonstrate how glutamate release from single CFs modulates excitability of neighboring PCs, thus expanding the influence of CFs on cerebellar cortical activity in a manner not predicted by anatomical connectivity. PMID:23707614

  15. Capturing the two dimensions of residential segregation at the neighborhood level for health research

    Directory of Open Access Journals (Sweden)

    Masayoshi eOka

    2014-08-01

    Full Text Available Two conceptual and methodological foundations of segregation studies are that (i segregation involves more than one group, and (ii segregation measures need to quantify how different population groups are distributed across space. Therefore, percentage of population belonging to a group is not an appropriate measure of segregation because it does not describe how populations are spread across different areal units or neighborhoods. In principle, evenness and isolation are the two distinct dimensions of segregation that capture the spatial patterns of population groups. To portray people’s daily environment more accurately, segregation measures need to account for the spatial relationships between areal units and to reflect the situations at the neighborhood scale. For these reasons, the use of local spatial entropy-based diversity index (SHi and local spatial isolation index (Si to capture the evenness and isolation dimensions of segregation, respectively, are preferable. However, these two local spatial segregation indexes have rarely been incorporated into health research. Rather ineffective and insufficient segregation measures have been used in previous studies. Hence, this paper empirically demonstrates how the two measures can reflect the two distinct dimensions of segregation at the neighborhood level, and argues conceptually and set the stage for their future use to effectively and meaningfully examine the relationships between residential segregation and health.

  16. Capturing the two dimensions of residential segregation at the neighborhood level for health research.

    Science.gov (United States)

    Oka, Masayoshi; Wong, David W S

    2014-01-01

    Two conceptual and methodological foundations of segregation studies are that (i) segregation involves more than one group, and (ii) segregation measures need to quantify how different population groups are distributed across space. Therefore, percentage of population belonging to a group is not an appropriate measure of segregation because it does not describe how populations are spread across different areal units or neighborhoods. In principle, evenness and isolation are the two distinct dimensions of segregation that capture the spatial patterns of population groups. To portray people's daily environment more accurately, segregation measures need to account for the spatial relationships between areal units and to reflect the situations at the neighborhood scale. For these reasons, the use of local spatial entropy-based diversity index (SHi ) and local spatial isolation index (Si ) to capture the evenness and isolation dimensions of segregation, respectively, are preferable. However, these two local spatial segregation indexes have rarely been incorporated into health research. Rather ineffective and insufficient segregation measures have been used in previous studies. Hence, this paper empirically demonstrates how the two measures can reflect the two distinct dimensions of segregation at the neighborhood level, and argues conceptually and set the stage for their future use to effectively and meaningfully examine the relationships between residential segregation and health. PMID:25202687

  17. Quantitative measurement of segregation phenomena in a binary-mixture fluidized bed by neutron radiography

    Science.gov (United States)

    Umekawa, Hisashi; Furui, Shuji; Oshima, Yoshihiro; Okura, Masashi; Ozawa, Mamoru; Takenaka, Nobuyuki

    2005-04-01

    Owing to a wide variety in fluidization properties of particles, segregation phenomena are hardly avoided in industrial fluidized-bed facilities. For the stability and controllability in the operation of such fluidized-beds, understanding of the relevant mechanism of particulate segregation is indispensable. Many factors, such as the difference in particle size, density, shape, and also arrangement of distributors, can be pointed out as the dominant causes for the segregation. Thus, any marking of particles for quantitative measurement may severely influence the segregation characteristic to be measured. But neutron radiography can be used for the quantitative measurement without disturbing the segregation characteristic. For estimating the segregation phenomena, evaluations of the particle fraction and the void fraction are required. For this purpose, two types of radiographies, i.e., X-ray and neutron radiographies were used in this investigation. Experimental results demonstrated the high performance of this method in investigating of segregation phenomena.

  18. Globular Clusters Hosting Intermediate-Mass Black Holes: No Mass-Segregation Based Candidates

    Science.gov (United States)

    Pasquato, Mario; Miocchi, Paolo; Won, Sohn Bong; Lee, Young-Wook

    2016-06-01

    Recently, both stellar mass segregation and binary fractions were uniformly measured on relatively large samples of Galactic globular clusters (GCs). Simulations show that both sizable binary-star populations and intermediate-mass black holes (IMBHs) quench mass segregation in relaxed GCs. Thus mass segregation in GCs with a reliable binary-fraction measurement is a valuable probe to constrain IMBHs. In this paper we combine mass-segregation and binary-fraction measurements from the literature to build a sample of 33 GCs (with measured core binary fractions), and a sample of 43 GCs (with binary-fraction measurements in the area between the core radius and the half-mass radius). Within both samples we try to identify IMBH-host candidates. These should have relatively low mass segregation, a low binary fraction (segregated (and show a larger binary fraction), confirming the theoretical expectation that the energy sources responsible for the large core are also quenching mass segregation.

  19. Polymer segregation under confinement: Influences of macromolecular crowding and the interaction between the polymer and crowders

    Science.gov (United States)

    Chen, Yuhao; Yu, Wancheng; Wang, Jiajun; Luo, Kaifu

    2015-10-01

    Entropy driven polymer segregation in confinements as a model for chromosome separation in bacteria has attracted wide attention; however, the effects of macromolecular crowding and the interaction between the binding protein and the newly replicated DNA on the segregation dynamics are not clear. Using Langevin dynamics simulations, we investigate the influences of crowders and the attractive interaction between the polymer and a small number of crowders on segregation of two overlapping polymers under a cylindrical confinement. We find that the segregation time increases with increasing the volume fraction of crowders due to the slower chain diffusion in crowded environments. For a fixed volume fraction of crowders, the segregation time decreases with increasing the size of crowders. Moreover, the attractive interaction between the polymer and a small number of crowders can significantly facilitate the chain segregation. These results are important for understanding the chromosome segregation in living cells.

  20. Segregation driven phase transformation in medium Mn steel

    OpenAIRE

    Kuzmina, Margarita

    2016-01-01

    Equilibrium segregation occurs as a result of structural inhomogeneities in the solid giving rise to sites for which solute atoms have a lower Gibbs energy. These sites occur at defects such as free surfaces, grain boundaries and phase interphases as well as at dislocations and stacking faults. All these regions then may exhibit concentrations of solute atoms that differ from each other and from that of the bulk material. Besides a strong impact on mechanical and physical properties of solids...