195 research outputs found

    Testing a global city hypothesis : an assessment of polarization across US cities

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    Social polarization is perhaps most evident within the world's large cities where we can easily observe stark contrasts between wealth and poverty. A world city theoretical perspective has emerged that associates large cities importance in a global network of cities to the degree of internal polarization within these cities. The research reported here locates 57 large US cities within this world city hierarchy and then empirically examines the hypothesized positive association between global centrality and social polarization using a multivariate, cross-city analysis. The findings are mixed, with some evidence that global centrality increases income polarization, but only in the context of higher levels of immigration. There is no evidence that a city's centrality affects occupational polarization. We conclude by suggesting implications for the world city literature and future research

    Chronology of Range Expansion of the Coyote, Canis latrans, in New York

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    Coyotes (Canis latrans) were historically restricted to central North America. In less than two centuries, however, Coyotes have colonized most of the continent, including much of northeastern North America. Better understanding causes and proximate mechanisms of this expansion requires a detailed understanding of how Coyotes colonized areas on a fine scale. We examined the establishment of Coyotes in the State of New York by collecting and analyzing reports of their first occurrence throughout the state over the past century, and creating a detailed map of range expansion. Coyotes first entered New York from the north, circled the Adirondack region prior to colonizing it, and then expanded southward and westward at ca. 78-90 km/decade. The revealed pattern lends little support to the hypotheses that the range expansion is attributable to translocations and releases, or that Coyotes were historically present in the region and only recently expanded in numbers. Rather, the data suggest a correlative relationship between anthropogenic land use and Coyote range expansion

    Understanding the Perceptions of Producers Regarding the Ogallala Aquifer Use: A Survey Report (2022)

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    This survey asked producers in the Ogallala aquifer how they view their role in groundwater use, what they see as the consequences of groundwater depletion, and why they believe groundwater should be conserved. Producers were also asked about their worldviews and values. Together, these questions help provide an understanding of the cultural state of the Ogallala aquifer, especially as it pertains to groundwater use

    The Synergistic Action of Melittin and Phospholipase A2 with Lipid Membranes: Development of Linear Dichroism for Membrane-Insertion Kinetics

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    Here we present data on the kinetics of insertion of melittin, a peptide from bee venom, into lipid membranes of different composition. Another component of bee venom is the enzyme phospholipase A2 (PLA₂). We have examined the interaction of melittin and PLA₂ with liposomes both separately and combined and demonstrate that they work synergistically to disrupt the membranes. A dramatic difference in the action of melittin and PLA₂ is observed when the composition of the membrane is altered. Temperature also has a large effect on the kinetics of insertion and membrane disruption. We use a combination of techniques to measure liposome size (dynamic light scattering), peptide secondary structure (circular dichroism spectroscopy), peptide orientation relative to the membrane (linear dichroism spectroscopy) and enzymatic digestion of the lipids (mass spectrometry)

    Attitude towards and factors affecting uptake of population based BRCA testing in the Ashkenazi Jewish population: a cohort study

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    Objective To evaluate factors affecting unselected‐population‐based‐BRCA‐testing in Ashkenazi‐Jews (AJ). Design Cohort‐study set within recruitment to the GCaPPS‐trial (ISRCTN73338115). Setting North‐London AJ‐population. Population or Sample AJ women/men >18‐years, recruited through self‐referral. Methods AJ‐women/men underwent pre‐test counselling for BRCA‐testing through recruitment clinics (clusters). Consenting individuals provided blood‐sample for BRCA‐testing. Socio‐demographic/family‐history/knowledge/psychological well‐being data along‐with benefits/risks/cultural‐influences (18‐item‐questionnaire measuring ‘attitude’) were collected. 4‐item likert‐scales analysed initial ‘interest’ and ‘intention‐to‐test’ pre‐counselling. Uni‐&‐multivariable logistic‐regression‐models evaluated factors affecting uptake/interest/intention‐to undergo BRCA‐testing. Statistical inference was based on cluster robust standard‐errors and joint Wald‐tests for significance. Item‐Response‐Theory and graded‐response‐models modelled responses to 18‐item questionnaire. Main Outcome Measures Interest, intention, uptake, attitude towards BRCA‐testing. Results 935 (women=67%/men=33%; mean‐age=53.8(S.D=15.02) years) individuals underwent pre‐test genetic‐counselling. Pre‐counselling 96% expressed interest but 60% indicated clear intention‐to undergo BRCA‐testing. Subsequently 88% opted for BRCA‐testing. BRCA‐related knowledge (p=0.013) and degree‐level education(p=0.01) were positively and negatively (respectively) associated with intention‐to‐test. Being married/cohabiting had four‐fold higher‐odds for BRCA‐testing uptake (p=0.009). Perceived benefits were associated with higher pre‐counselling odds for interest and intention‐to undergo BRCA‐testing. Reduced uncertainty/reassurance were the most important factors contributing to decision‐making. Increased importance/concern towards risks/limitations (confidentiality/insurance/emotional‐impact/inability to prevent cancer/marriage‐ability/ethnic‐focus/stigmatization) were significantly associated with lower‐odds of uptake‐of BRCA‐testing, and discriminated between acceptors and decliners. Male‐gender/degree‐level‐education (p=0.001) had weaker, while having children had stronger (p=0.005) attitudes towards BRCA‐testing. Conclusions BRCA‐testing in the AJ‐population has high acceptability. Pre‐test counselling increases awareness of disadvantages/limitations of BRCA‐testing, influencing final cost‐benefit perception and decision‐making on undergoing testing. This article is protected by copyright. All rights reserved

    Same-day diagnostic and surveillance data for tuberculosis via whole genome sequencing of direct respiratory samples

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    Routine full characterization of Mycobacterium tuberculosis (TB) is culture-based, taking many weeks. Whole-genome sequencing (WGS) can generate antibiotic susceptibility profiles to inform treatment, augmented with strain information for global surveillance; such data could be transformative if provided at or near point of care. We demonstrate a low-cost DNA extraction method for TB WGS direct from patient samples. We initially evaluated the method using the Illumina MiSeq sequencer (40 smear-positive respiratory samples, obtained after routine clinical testing, and 27 matched liquid cultures). M. tuberculosis was identified in all 39 samples from which DNA was successfully extracted. Sufficient data for antibiotic susceptibility prediction was obtained from 24 (62%) samples; all results were concordant with reference laboratory phenotypes. Phylogenetic placement was concordant between direct and cultured samples. Using an 70 Illumina MiSeq/MiniSeq the workflow from patient sample to results can be completed in 44/16 hours at a reagent cost of ÂŁ96/ÂŁ198 per sample. We then employed a non-specific PCR-based library preparation method for sequencing on an Oxford Nanopore Technologies MinION sequencer. We applied this to cultured Mycobacterium bovis BCG strain (BCG), and to combined culture negative sputum DNA and BCG DNA. For flowcell version R9.4, the estimated turnaround time from patient to identification of BCG, detection of pyrazinamide resistance, and phylogenetic placement was 7.5 hours, with full susceptibility results 5 hours later. Antibiotic susceptibility predictions were fully concordant. A critical advantage of the MinION is the ability to continue sequencing until sufficient coverage is obtained, providing a potential solution to the problem of variable amounts of M. tuberculosis in direct samples

    Developing a sustainability science approach for water systems

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    We convened a workshop to enable scientists who study water systems from both social science and physical science perspectives to develop a shared language. This shared language is necessary to bridge a divide between these disciplines’ different conceptual frameworks. As a result of this workshop, we argue that we should view socio-hydrological systems as structurally co-constituted of social, engineered, and natural elements and study the “characteristic management challenges” that emerge from this structure and reoccur across time, space, and socioeconomic contexts. This approach is in contrast to theories that view these systems as separately conceptualized natural and social domains connected by bi-directional feedbacks, as is prevalent in much of the water systems research arising from the physical sciences. A focus on emergent characteristic management challenges encourages us to go beyond searching for evidence of feedbacks and instead ask questions such as: What types of innovations have successfully been used to address these challenges? What structural components of the system affect its resilience to hydrological events and through what mechanisms? Are there differences between successful and unsuccessful strategies to solve one of the characteristic management challenges? If so, how are these differences affected by institutional structure and ecological and economic contexts? To answer these questions, social processes must now take center stage in the study and practice of water management. We also argue that water systems are an important class of coupled systems with relevance for sustainability science because they are particularly amenable to the kinds of systematic comparisons that allow knowledge to accumulate. Indeed, the characteristic management challenges we identify are few in number and recur over most of human history and in most geographical locations. This recurrence should allow us to accumulate knowledge to answer the above questions by studying the long historical record of institutional innovations to manage water systems
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