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251.
采用艾森克个性问卷及自编基本情况调查表对395名未成年男犯进行调查,结果显示,未成年男犯在文化程度、作案地区、家庭结构及家庭教养方式等方面存在新的变化趋势,犯罪原因集中在家庭、学校、社会及个人心理因素等各方面。  相似文献   
252.
ABSTRACT

Despite its global popularity over the past few decades, the public-private partnership (PPP) has not always led to successful outcomes, due largely to a number of risk factors associated with the projects. To explain how and why PPPs sometimes fail, this study considers the success-failure continuum of Singapore’s recent PPP experience from 2000 to 2019. After taking a critical, close look at the six failed cases, we identify the following latent risk factors: unstable financial capacity during the execution period of a project, force majeure unforeseen problems that arise, a lack of technical and/or financial foresight, poor corporate management (e.g. delays in construction and poor-quality service delivery), and an unfavourable investment environment stemming from the lack of a clear and supportive governance framework. In addition, we find that most risk factors tend to appear during the contract management (pre-operation) and project management (operation) phases. Such risks seem to drive the operational failure and subsequent contract termination of multiple unsuccessful PPPs, simultaneously (and sometimes sequentially) rather than in isolated fashion. All in all, this study offers for policymakers that better risk allocation and proper, mutual coordination between the public and private partners represent essential factors for PPP success.  相似文献   
253.
利用PCR技术扩增西尼罗病毒(WNV)E蛋白基因并将其插入原核表达载体pET-30a(+),构建重组质粒pET-30a(+)-WNV-E,并转化至大肠杆菌BL21(DE3)感受态细胞中,经IPTG诱导目的蛋白表达,对诱导条件进行优化,利用His镍柱亲和层析法纯化目的蛋白,纯化后的蛋白经SDS-PAGE与Westernblot鉴定正确后,免疫BALB/c小鼠制备多克隆抗体并进行间接免疫荧光鉴定。结果显示:WNV E蛋白在大肠杆菌中以包涵体形式被成功表达,蛋白最佳诱导条件为37℃,0.8 mmol/L IPTG诱导5 h,经间接免疫荧光鉴定多克隆抗体能特异性识别WNV E蛋白。本研究成功表达并纯化了WNV E蛋白,证明该蛋白具有良好的免疫原性,为WNV抗原、抗体检测方法的建立和新型疫苗的研发及相关研究奠定了基础。  相似文献   
254.
Objectives

The current study proposes an approach that accounts for the importance of streets while at the same time accounting for the overlapping spatial nature of social and physical environments captured by the egohood approach. Our approach utilizes overlapping clusters of streets based on the street network distance, which we term street egohoods.

Methods

We used the street segment as a base unit and employed two strategies in clustering the street segments: (1) based on the First Order Queen Contiguity; and (2) based on the street network distance considering physical barriers. We utilized our approaches for measuring ecological factors and estimated crime rates in the Los Angeles metropolitan area.

Results

We found that whereas certain socio-demographics, land use, and business employee measures show stronger relationships with crime when measured at the smaller street based unit, a number of them actually exhibited stronger relationships when measured using our larger street egohoods. We compared the results for our three-sized street egohoods to street segments and two sizes of block egohoods proposed by Hipp and Boessen (Criminology 51(2):287–327, 2013) and found that two egohood strategies essentially are not different at the quarter mile egohood level but this similarity appears lower when looking at the half mile egohood level. Also, the street egohood models are a better fit for predicting violent and property crime compared to the block egohood models.

Conclusions

A primary contribution of the current study is to develop and propose a new perspective of measuring neighborhood based on urban streets. We empirically demonstrated that whereas certain socio-demographic measures show the strongest relationship with crime when measured at the micro geographic unit of street segments, a number of them actually exhibited the strongest relationship when measured using our larger street egohoods. We hope future research can use egohoods to expand understanding of neighborhoods and crime.

  相似文献   
255.
Abstract

Prior studies suggest that fiscal slack may positively affect technological innovation in the public sector but yield inconsistency between theoretical expectations and empirical findings. To address this research gap, this study develops a configurational explanation combining fiscal slack and environmental pressures by employing fs-QCA in the context of Chinese provincial governments’ online public service provision. The findings reveal that the role of fiscal slack is environmentally dependent on explaining technological innovation and that environmental pressures seem to be more important. That is, fiscal slack is likely irrelevant to a high degree of technological innovation assimilation, while the demanding environments of multiple environmental pressures matter. Relative fiscal scarcity may be somewhat relevant to a low degree of technological innovation assimilation only when combined with a more relaxed environment. Several theoretical and practical implications are discussed.  相似文献   
256.
ABSTRACT

The need for new and stronger middle power diplomacy is growing as global challenges are increasingly governed by various horizontal inter- and trans-national networks. Climate change is one of the most complex and urgent global challenges that require collective action, and it is an issue for which more middle power leadership is greatly needed. The Republic of Korea (ROK) has been successful in becoming a primary actor in green growth governance, and its success has been attributed to its strategic middlepowermanship, integrating both material and ideational contents. Reducing emissions from deforestation and forest degradation (REDD+) in tropical developing countries has been lauded as an immediate and effective solution to mitigate climate change. ROK's unique history of forest transition before rapid economic growth highlights the fact that improving forest management is possible even with imperfect governance, rapid population growth, and low economic development. The lessons learned from ROK's forest transition can be developed as a distinct contribution to the international effort to address forest-related impacts on climate change, and offer an important opportunity for ROK to play a constructive role and achieve enhanced stature within the international community.  相似文献   
257.
This article examines the institutional factors that influence the implementation of open data platforms in U.S. cities. Public management scholarship has argued that governance can be transformed by new information technologies that improve transparency and engagement, reduce administrative costs, and support performance management systems. However, this argument ignores key risks for administrators, as well as institutional and political obstacles that can thwart implementation. This article uses hierarchical negative binomial regression to analyze the organizational and institutional features influencing implementation in more than 1,500 departments across 60 cities. Department type and administrative capacity are strongly associated with the number of open data files available, while city-level institutional characteristics and administrative capacity are not significant factors. Municipal demographics are also identified as a factor, suggesting a potential demand-side influence from wealthy and technologically proficient residents. Evidence for Practice
  • The implementation of open data policies benefits from targeted approaches at the department level rather than uniform, citywide objectives or requirements.
  • City executive-level positions such as chief data or information officers are not necessarily associated with successful implementation, measured by the number of open data files made available.
  • Open data implementation involves additional administrative responsibilities and labor at the department level, so city administrators looking to expand the number and variety of data sets available through their open data platforms should devote time and resources to working directly with departments to facilitate and encourage data sharing.
  • Administrators looking to expand the number and variety of data sets available through their open data platforms should consider the costs associated with investing in increasing individual departments’ abilities to balance the additional administrative responsibilities and labor involved.
  相似文献   
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260.
Deaths occurring due to rattlesnake envenomization are extremely rare and must be thoroughly investigated in the same manner as any other type of death. Our research presents the case of an adult white male who suffered a fatal timber rattlesnake (Crotalus horridus) envenomation in northwest Florida in 2018. Blood samples were taken from the decedent's heart and vasculature of the chest and sent for serum proteomic analysis. Serum proteomic analysis was utilized in order to identify proteins from timber rattlesnake (C. horridus) found within the victim's blood. The confirmation of the presence of timber rattlesnake venom within the victim's blood allows the forensic pathologist to determine the cause of death most accurately and likewise, assists with the manner of death determination. Blood samples were separated into two groups: one with the abundant endogenous proteins depleted to facilitate detection of lower abundant proteins and one undepleted. In the depleted sample, a total of 712 proteins were identified, with 47 of the proteins (6.6%) occurring originating from timber rattlesnake (C. horridus). Likewise, a total of 742 proteins were identified in the undepleted sample, with 52 of the proteins (7.0%) occurring in timber rattlesnake (C. horridus). No timber rattlesnake (C. horridus) proteins were found in control human serum.  相似文献   
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