Blind validation of postmortem interval estimates using developmental rates of blow flies

This study evaluated the use of different degree day (DD) models, developmental thresholds and developmental data sources for estimating postmortem interval (PMI) based on developmental rates of blow flies (Diptera: Calliphoridae). Blow fly evidence was collected from three mock crime scenes and sent for blind analysis of PMI. PMI estimates were calculated using averaging, single sine, double sine, single triangle, and double triangle models of DD calculation with minimum developmental thresholds of 0, 6 and 10 °C and Anderson's, Byrd and Allen's, Greenberg's, Nishida's and Kamal's developmental data sets. These estimates were compared with the actual PMI to determine which combination of DD model, developmental threshold and developmental data provided the most accurate estimate. For all three cases, at least one method gave a PMI estimation that was within 1 day of the actual date of death. There was no variability between PMI estimated using the five models of DD calculation. Overall, as lower developmental threshold increased, the PMI interval estimates increased. Depending on the developmental data set used, increasing the lower developmental threshold caused some overestimations of the date of oviposition, with estimates given that were prior to the actual death. Future PMI estimates should include error ranges, so that overestimation of PMI is avoided.     

Survival analysis: A survey

This paper is a survey of statistical methods used to analyze the length of time until a specified event occurs. These models have often been used to analyze the survival times (i.e., time until death) of medical patients, and so the term survival analysis is natural. In criminology, the main application of these models has been to analyze the time until recidivism, but many other applications are possible. The paper summarizes the statistical literature on survival analysis, and describes its applications in criminology. The methods are illustrated by an application to the prediction of time until recidivism for a sample of North Carolina prison releasees.     

Detection of Gamma-Hydroxybutyric Acid in Various Drink Matrices via AccuTOF-DART*

Abstract: A new screening method for detecting gamma-hydroxybutyric acid (GHB) in drink matrices, using the IonSense, Inc. (Saugus, MA) direct analysis in real time (DART) ion source coupled to a JEOL exact mass time-of-flight mass spectrometer (AccuTOF), was validated and compared with the current screening methodology. The DART ion source allows for analysis of samples under ambient conditions with little to no sample preparation. Fifty drink specimens were spiked at levels of 1, 2, 3, and 4 mg/mL GHB, and analyzed on the AccuTOF-DART. Positive detection of GHB occurred for each of the samples at each concentration level, giving 100% accuracy for the samples tested. Twenty-five of the 50 drink specimens were spiked at 1 mg/mL GHB and tested using a color test known as the GHB Color Test #3. Only two of these 25 specimens tested positive for the presence of GHB, giving only 8% accuracy. Implementation of this new methodology as a screening tool for GHB analysis will quickly eliminate negative specimens allowing the examiner to focus analysis time on those that screened positive.     

A survival model with dependent competing events and right-hand censoring: Probation and parole as an illustration

Researchers are frequently interested in estimating the elapsed time until the occurrence of an event, such as an arrest following release from prison, dissolution of a marriage, and death following the onset of a disease. Estimation is often hindered by the occurrence of a competing event, which prevents the event of interest from being observed, and by limited follow-up periods. A parametric procedure developed in this paper is suitable for dealing with nonrepeatable competing events when the events are correlated and when independent righthand censoring also exists. Weak distributional assumptions are accommodated by using a Box-Cox transformation and by explicit modeling of heteroscedasticity. The procedure is applied to data pertaining to failure on probabation and parole.     

马克思主义时代化的路径探析

时代性是马克思主义的本质属性。作为不断发展的理论,马克思主义的每一次历史性飞跃,都带有深刻的时代烙印,都是马克思、恩格斯、列宁、毛泽东、邓小平等马克思主义者在马克思主义基本原理的指导下精细考察时代特征、准确把握时代脉搏、深刻洞察时代趋势的基础上,把对马克思主义的"文本解读"与对各个历史时期的"时代解读"相结合,不断实现马克思主义时代化的过程。"文本解读"与"时代解读"相结合,是实现马克思主义时代化的根本途径。     

时间抑或地域——宪法学研究之中国性

学术研究有其存在的历史境域。对一个学科而言,只有在贴合具体的历史境域下讨论该学科的学术研究,讨论该学科的发展方向时才具有意义。从我国历史上看,宪法学研究从清末开始,到现在已有100多年,无论其几经沧海桑田,但它之所以可以沿称到现在,自有它自立的关切方法、问题和理论体系。中国宪法研究的中国性问题,不仅涉及宪法学在中国的时间性差别问题,也涉及其地域性差别问题。     

中国南北分开过春节：破解春运难题的制度性路径

春节是中国最重要的一个传统节日，但伴随着春节出现的春运问题一直是中国的社会难题，尽管近年来中国交通有了巨大的发展。当物质的、技术的手段无法解决春运难题时，从变革制度入手，中国南北在时间上分开过春节可以彻底解决这一难题。     

Development and validation of the Cozart DDS oral fluid collection device

The testing of oral fluid for drugs of abuse has increased significantly over recent years and is now commonplace in drug rehabilitation clinics, the workplace, prisons and custody suites. The global problem of identifying drugged drivers has also led to an increase in oral fluid testing at the roadside. The main requirements for the implementation of roadside drug testing are a rapid sample collection time, collection of a known sample volume and recovery of drugs from the collection device. We report here the development of the Cozart^® DDS oral fluid collector, an oral fluid collector that combines rapid and adequate sample collection with satisfactory drug recovery. Oral fluid was collected from drug users (n = 134) and drug-free individuals (n = 137), using the Cozart^® DDS oral fluid collector. The mean time for the completion of collection (full coloration of the sample presence indicator) was 34 s for drug-free individuals and 44 s for drug users. The average volume collected was 0.34 mL (n = 271). No chemical stimulant (to induce salivation) was used to achieve the collection times observed in either the drug-free or the drug-taking sample populations. Drugs were extracted from the collector using the Cozart^® DDS buffer and drug recovery was determined by Cozart^® enzyme immunoassays. The recovery studies showed that for amphetamine, Δ⁹THC, cocaine, methadone, methamphetamine, morphine and temazepam over 90% of the drug in the sample was eluted from the collector. The Cozart^® DDS oral fluid collector provides a reliable mechanism for the collection of oral fluid at the roadside that achieves the rapid collection times required.     

转型时期制约行政监督效能提升的主体因素

本文分析了转型时期制约行政监督效能提升的五个主体因素，即效能理念、专业人才、策略运用、资源建设和有效管理，在此基础上对转型时期如何提升行政监督效能提出了相应的对策。     

城镇已婚女性的工作与家庭冲突研究——基于时间利用的分析

利用第三期中国妇女社会地位调查资料,从时间利用的视角分析城镇已婚职业女性的工作与家庭冲突状况发现,婚姻和生育是女性平衡工作与家庭关系面临的巨大挑战,工作时间的刚性减少了女性对家庭的时间投入,城镇已婚在业女性比男性面临更大的工作与家庭冲突,公共服务的供给可在一定程度上缓解这种矛盾和冲突。在政策方面,建议推动用人单位公平对待职业女性,有条件地实行弹性工作制;政府要增加公共服务供给,提高服务水平;同时倡导男女共同承担家庭责任。