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1.
Cyanide is a highly toxic agent that has been frequently used for suicide in South Korea. It is also used in various industrial fields, such as metal plating, in which many accidental cyanide intoxications have occurred. To overcome the disadvantages of conventional cyanide analysis methods, a simple and fast method for the analysis of cyanide in whole blood using ion chromatography (IC) with amperometric detection was developed in this study. Whole blood samples were deproteinized, diluted, and analyzed using an IC–amperometric detection system. The limits of detection and quantitation were 0.1 and 0.2 mg/L, respectively. The method showed good linearity in the range of 0.2 to 50 mg/L with R2 > 0.99. The intra- and inter-assay precision and accuracy values were <10%. The established method was successfully applied to analyze whole blood samples from three cyanide intoxication cases.  相似文献   
2.
Journal of Youth and Adolescence - Language brokering is a prevalent phenomenon in ethnic minority immigrant populations. Although accruing evidence points to the beneficial impacts of healthy role...  相似文献   
3.
The increased use of information and communication technologies (ICTs) has triggered enormous innovation in the public sector and created positive public value at the managerial, delivery of services, and policy levels. However, these positive outcomes do not automatically accrue simply by adoption of ICTs as public leaders can fail to adopt relevant new ICTs, use them poorly, or use them in ways that actually diminish public value, which raises the question of the importance of e-leadership. This article examines e-leadership and innovation capacity at the individual public manager level and fills in some gaps about the practice and implementation of ICTs in the public sector. We explore eight research questions useful in theorizing about e-leadership, develop constructs of e-leadership, and describe the current development of e-leadership. By comparing e-leadership in two country settings (South Korea and the United States), we also overcome the limitations of the existing Western-oriented studies about innovations in the public sector. In addition to the growth of e-leadership use and requirements for a variety of competencies equivalent to, but separate from, traditional communication competences, we find that national cultures exert significant influence on the major constructs of e-leadership, which implies that an effective e-leadership strategy should consider cultural contexts seriously.  相似文献   
4.
Cholesterol and squalene are fatty materials of latent fingermarks that can be utilized for dating methodologies and visualization techniques. Previous studies have suggested these compounds undergo degradation in fingermarks as a function of time (days) and light at ambient temperature. However, studies assessing how their composition changes at low and high temperatures over short periods of time (hours) have not been published previously. Here, we performed quantitative analysis of cholesterol and squalene in natural fingermark residue using PVDF membrane, after exposure to a range of temperatures (−20 to 100°C) for 4 and 8 h. We found that levels of both fatty materials remained constant at −20 to 60°C, but both showed significant reduction at 100°C, over short exposure times. These results indicate that cholesterol and squalene are detectable at −20 to 60°C, whereas at 100°C or higher, both are lost due to rapid thermal degradation.  相似文献   
5.
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   
6.
Species identification of necrophagous insects found on a dead body is an essential key in applying medicolegal entomology to the estimation of postmortem interval (PMI). Due to limited morphological identification of insect evidence, several studies have identified species using molecular information such as DNA markers. While considerable cytochrome c oxidase subunit I (COI) gene sequence data of necrophagous fly species have been collected and annotated, those of necrophagous beetle species have not. Since necrophagous beetles such as Dermestes species have a larval period longer than that of flies, beetles are useful in even the late decomposition phase in estimating minimum PMI. To obtain the full-length COI gene sequences of six Dermestes species collected from South Korea, we designed primers for polymerase chain reaction amplification and sequencing. The obtained full COI nucleotide sequences were used for performing phylogenic analysis and comparison with previously reported sequences. The results demonstrated that the COI gene sequences could be used to identify forensically important Dermestes species in South Korea.  相似文献   
7.
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   
8.
This study provides a systematic review of the development of Chinese public administration in English language journals. An analysis of articles in the top 25 English-language public administration journals worldwide from 1996 to 2016 confirmed increases in both the number and significance of studies of Chinese public administration. A systematic content analysis of abstracts of previous studies was performed and showed that social development and administrative reform were among the most important topics. With respect to the methodology of this study, qualitative methods were more frequently used than quantitative or mixed methods. Finally, implications for future research on Chinese public administration are discussed.  相似文献   
9.

Research on the health benefits and consequences of close relationships has suggested the linkage in daily emotions (i.e., coregulation) between close partners is an important relationship dynamic. While the coupling of daily emotions among family members (parent–child and marital dyads) has been widely documented, research examining emotional coregulation among ethnic minority youth during adolescence, a period marked by heightened emotion and risk for psychopathology, remains an important area in need of exploration. This study examined correlates of emotional coregulation in a sample of Mexican-origin adolescents (Mage?=?15.02, SD?=?.83) and their parents (Mage?=?41.93, SD?=?6.70). Dyads reported on daily levels of distress and happiness for 14 consecutive days across two waves of data collection a year apart (nwave1?=?428 dyads, nwave2?=?336 dyads). Dyads who reported getting along were more likely to coregulate their daily happiness. Importantly, coregulation of distress was only present in older adolescents who reported above average levels of internalizing symptoms. The results suggest coregulation of distress may shape or be shaped by poor mental health during the later years of adolescence, a time when youth may be establishing a degree of emotional autonomy from parents.

  相似文献   
10.
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