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121.
This article considers how spatial analysis of housing submarkets can advance research into residential segregation. While an emphasis on housing submarkets has been proposed as a new construct for modeling housing prices, its use in analyzing residential segregation has been limited. Recent advances in spatial analysis and geographic information systems present new opportunities for researchers to exploit the potential of housing submarkets as constructs that offer a more precise way to examine residential segregation. The article synthesizes literature related to residential segregation and housing submarkets and demonstrates how to delineate housing submarkets using publicly available data. It examines the spatial distribution of housing submarkets and how the socially disadvantaged are represented across housing submarkets in St. Louis, Missouri, and Cincinnati, Ohio, to conclude that St. Louis's housing market is more polarized and racially segregated than Cincinnati's. Spatial analysis of housing submarkets, in conjunction with archival analysis, provides a promising avenue for identifying residential segregation as a multidimensional phenomenon, and a means to explore local processes of urban inequality.  相似文献   
122.
In mortality research, much attention has been paid to the strong geographical differentials in mortality levels and in modern mortality decline, as the analysis of this geographical differentiation might hold the key to explaining the determinants of mortality change. The use of historical cause-specific mortality data has proved a challenging, although very insightful, means to this end. The four contributions to this special issue focus on cause-specific mortality in the past, both to reassess older data using new insights and to challenge existing insights by using new data and methods. These papers, of which earlier versions were presented during the thirty-eighth Social Science History Association (SSHA) Meeting in Chicago, 21–24 November 2013, explore mortality at different stages of the life course, ranging from early infancy to old age. Moreover, each paper revolves around a different group of causes of death. Although the papers are in many ways rather different, together they demonstrate how different data, theoretical frameworks and methodologies can push the boundaries of research into the trends and determinants of historical mortality patterns.  相似文献   
123.
One of the main problems faced by social historians of the Cossack Hetmanate (Cossacks' autonomous territory situated on the Left Bank of the Dnieper River) is a poor knowledge of population issues. This article therefore focuses on the history of the family and households in eighteenth-century Ukraine. Unlike the historiography of Western Europe, where active research in this field started in the 1960s, contemporary Ukrainian historiography includes only a few studies dedicated to these issues. Recently renewed interest in population issues is due to the widening scope of historical research and to changes in the methodological paradigm that started in the twenty-first century. Historical research of the Ukrainian family and population is thus in its infancy and reconsidering these aspects is crucial for a global scholarship.  相似文献   
124.
This article explores the interplay between international donors and local NGOs in Kyrgyzstan's HIV/AIDS sector. It argues that donors have transposed ready-made policies without sufficient consideration of the local context and that NGOs have responded strategically, adapting their proposals and reports to the expectations of donors. This complex interplay has resulted in unintended consequences that have undermined an effective response to the HIV/AIDS epidemic. It has given rise to ‘virtual realities’ detached from developments on the ground. The funding system has also led to corruption and misappropriation of funds and the failure of NGOs to become sustainable. Largely bypassing the state in the allocation of funds, international donors have also undermined an already weak state.  相似文献   
125.
Opioid‐related mortality happens, even in healthcare settings. We describe serial postmortem fentanyl blood concentrations in a hospital inpatient who fatally abused transdermal fentanyl. This is a single‐patient case report. A 42‐year‐old man with lymphoma was started on transdermal fentanyl therapy while hospitalized for chronic abdominal pain. The patient was last seen awake 1.3 h prior to being found apneic and cyanotic. During the resuscitation attempt, a small square‐shaped film was removed from the patient's oropharynx. Femoral blood was collected 0.5 and 2 h postmortem, and the measured fentanyl concentration increased from 1.6 to 14 ng/mL. Study limitations include potential laboratory or collection errors and missing data. (i) Providers must be vigilant for signs of fentanyl patch abuse. (ii) Postmortem blood concentrations are not static postmortem, likely secondary to decreasing pH, increased aqueous solubility, and tissue redistribution, and are therefore unlikely to accurately represent antemortem blood concentrations.  相似文献   
126.
Whereas one line of recent neighborhood research has placed an emphasis on zooming into smaller units of analysis such as street blocks, another line of research has suggested that even the meso‐area of neighborhoods is too narrow and that the area surrounding the neighborhood is also important. Thus, there is a need to examine the scale at which the social ecology impacts crime. We use data from seven cities from around the year 2000 to test our research questions using multilevel negative binomial regression models (N = 73,010 blocks and 8,231 block groups). Our results suggest that although many neighborhood factors seem to operate on the microscale of blocks, others seem to have a much broader impact. In addition, we find that racially and ethnically homogenous blocks within heterogeneous block groups have the most crime. Our findings also show the strongest results for a multitude of land‐use measures and that these measures sharpen some of the associations from social characteristics. Thus, we find that accounting for multiple scales simultaneously is important in ecological studies of crime.  相似文献   
127.
目的建立较为快速准确的合成大麻素K3中AKB48的气相色谱/质谱检验方法。方法对进样口温度、初始柱温、柱流速及质谱采样率等4项色谱及质谱实验参数进行考察优化。结果 GC/MS检验合成大麻素K3中AKB48的优化条件为:进样口温度280℃,柱初始温度80℃,柱流速为2.0ml/min,质谱采样率为2。结论该方法具有快速、准确、灵敏等优点,可用于K3中AKB48的定性检验鉴定。  相似文献   
128.
GC/MS/MS时间编程在火灾现场助燃剂检测中的应用   总被引:4,自引:0,他引:4  
运用Varian SATURN2000气质联用仪通过GC/MS、GC/MS/MS、时间编程 GC/MS/MS对汽油样品进行分析比对,发现利用时间编程GC/MS/MS,对检测火灾现场残留汽油效果很好,可彻底排除样品中基体的背景干扰,大大提高检测灵敏度;同时对混合助燃剂(汽油+煤油、汽油+柴油)进行了实验探索。  相似文献   
129.
体液中氟乙酰胺SPE-GC/MS检测   总被引:1,自引:1,他引:0  
目的 利用GC/MS与固相萃取 (SPE)技术相结合 ,开发血和尿样中氟乙酰胺鼠药的GC/MS定量分析新方法 ,并用于实际案例检测。方法 选择乙酰胺为内标 ,通过比较不同固相柱的萃取效率和不同条件对回收率的影响 ,优化用于血和尿样中氟乙酰胺萃取的固相柱和提取条件 ,利用氟乙酰胺与乙酰胺质谱图的分子离子峰面积之比与氟乙酰胺浓度的定量关系 ,建立血和尿样中氟乙酰胺鼠药的GC/MS定量分析新方法。结果 用硅胶柱萃取 ,峰面积之比与氟乙酰胺浓度在 5 0~ 90 μg/ml范围呈线性关系 ,检测限为 1 0 μg/ml。血样中氟乙酰胺检测的平均回收率达 91 6% ,标准偏差小于 7 3 %。结论 此法对实际样品的测定证明可满足氟乙酰胺鼠药中毒的定性定量要求。  相似文献   
130.
罗芳  刘颖 《刑事技术》2006,(2):24-26
目的建立苯二氮卓类药物氯氮平的串联质谱检验方法,以排除干扰物质,提高灵敏度。方法用串联质谱方法分析。结果以基峰m/z243为母离子,碰撞诱导电压(CID)为0.8v,进行MS/MS分析。结论与GC/MS相比,GC/MS/MS方法选择性好、灵敏度最高,排除干扰性能强。  相似文献   
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