Further investigations into the speed of cerebral swelling following blunt cranial trauma

An anesthetized sheep model of traumatic brain injury (TBI) has been developed to assess early changes in intracranial pressure (ICP) following closed head injury. Immediately after TBI, a transient (<10 min) hypertensive response occurred, followed by significant and prolonged systemic hypotension. ICP demonstrated a biphasic response, being seven times baseline values of 8 ± 2 mm Hg 10 min after injury, decreasing to 25 ± 2 mm Hg by 30 min, and then increasing to values exceeding 30 mm Hg by 4 h postinjury. ICP was always significantly higher than baseline values, which combined with hypotension, reduced cerebral perfusion pressure to less than 60% of normal. This early and sustained increase in ICP after craniocerebral trauma acutely alters cerebral perfusion pressure and brain oxygenation and provides a potential pathophysiological explanation for immediate clinical manifestations in humans following significant TBI.     

The rate of dissipation of mouth alcohol in alcohol positive subjects

Seven subjects participated in a two-part study to evaluate mouth alcohol dissipation in alcohol positive subjects. In part one, subjects rinsed their mouths with a vodka solution and were breath tested after 1, 2, 3, 4, and 5 min intervals. On average, breath alcohol concentration (BrAC) decreased 20.4% (range 3.2-47.9%) between 1 and 2 min after rinsing. In part two of the study, multiple breath tests were administered after rinsing once with the vodka solution. The BrAC decreased more than 0.020 g/210 L between the first and second tests for all subjects (average 0.095 g/210 L, range 0.021-0.162 g/210 L). The average time for subjects to reach their unbiased BrAC was 9.35 min (range 4-13 min) after rinsing. This study reaffirms the need for duplicate breath testing and confirms that the minimum of a 15-min observation period is sufficient for mouth alcohol to dissipate in alcohol positive subjects.     

自然法抑或实证法——理性与意志视野下的美国宪法

在看待美国宪法观念中,一种观念将美国宪法视为自然法或高级法的摹本,认为美国宪法的特征在于人类凭借理性发现和宣布了自然法或高级法;另一种观念则将美国宪法视为纯粹的人民主权的意志表达。这两种观念都存在一定的曲解:美国宪法其实和古典自然法之间存在着巨大的断裂,是一种现代自然权利体系之下的人为宪法,但这种宪法并不是未经筛选的人民意志的表达,而是理性引导之下的意志表达。美国宪法的这种特征要求当代的法律人政治家既不能神话宪法,也不能轻视宪法,而是要求将宪法视为政治科学的教材,通过理解与对话来提升理性,从而思考宪法在当代的挑战。     

大力发展健康向上的老年文化

发展健康向上的老年文化是构建和谐社会的必然要求,是尽快消除文化阳光照不到的＂盲区＂的客观要求。健康向上的老年文化是以先进文化为主导的文化,是颐养身心的健康文化,是尊老敬老的传统文化。大力发展健康向上的老年文化需要多管齐下,采取多种措施：要由老龄委牵头多部门共管,创建老年文化精品工程;建立保障老年文化服务资金的长效机制;引进市场机制,发展优秀老年文化产业;加强人才队伍建设,开展丰富多彩的老年文化活动。     

A Radiographic Study on the Utility of Cranial Vault Outlines for Positive Identifications

A standard method for positive identification is the use of antemortem and postmortem radiographic comparisons. The purpose of this research is to test the visual accuracy of antemortem and postmortem radiographic comparisons of cranial vault outlines and to evaluate their uniqueness using geometric morphometric methods. A sample of 106 individuals with varying levels of education and forensic case experience participated in a visual accuracy test. Of the 106 individuals, only 42% correctly assigned all of the radiographs, with accuracy rates ranging from 70 to 93% for each radiographic comparison. Vault shape was further examined using elliptic Fourier analysis, and paired t‐tests were computed on the first 10 principal components accounting for 100% of the variance, which found no significant differences. The visual accuracy test and elliptic Fourier analysis shows that vault outlines may not be unique enough for positive identifications when used as a sole indicator.     

新冠肺炎疫情对宏观经济的影响分析及政策建议

该文通过对比分析发现,由于疫情影响地域范围、停复工时间和经济结构等因素存在差异,新冠肺炎疫情对经济的短期影响会大于2003年非典疫情;而且,由于部分民企和居民等微观主体的抗风险能力更弱,存在传导形成次生风险的可能。因此,必须坚持疫情防控和经济托底相结合,发挥逆周期政策作用,切实降低此次疫情的负面经济影响。     

Tackling the Big Questions in Social Impact Bond Research through Comparative Approaches

Abstract

This special issue of theJournal of Comparative Policy Analysis brings together four cross-disciplinary articles representing the first concerted attempt to combine comparative approaches to extend theoretical and empirical understandings of Social Impact Bonds (SIBs). SIBs are investment-backed payment-by-results projects and have been subject to vigorous academic debate on their appropriateness and efficacy since the first SIB launched in 2010. This introduction to the special issue outlines the state of the academic literature on SIBs, identifying gaps and suggesting five big questions that do not yet have satisfactory answers: (1) What are the administrative or political problems to which SIBs respond? (2) Where and why do SIBs emerge in particular contexts? (3) What is the role of SIBs in the evidence-based policy movement? (4) Is delivering an intervention through a SIB more effective than other means and are associated costs justifiable? (5) Do SIBs catalyse wider organizational, system, or institutional changes? This introduction then summarizes the articles included in this special issue, discusses how they respond to these big questions, and suggests that further comparative research might best address remaining gaps in the literature.     

Fingerprint error rate on close non‐matches

The accuracy of fingerprint identifications is critically important to the administration of criminal justice. Accuracy is challenging when two prints from different sources have many common features and few dissimilar features. Such print pairs, known as close non‐matches (CNMs), are increasingly likely to arise as ever‐growing databases are searched with greater frequency. In this study, 125 fingerprint agencies completed a mandatory proficiency test that included two pairs of CNMs. The false‐positive error rates on the two CNMs were 15.9% (17 out of 107, 95% C.I.: 9.5%, 24.2%) and 28.1% (27 out of 96, 95% C.I.: 19.4%, 38.2%), respectively. These CNM error rates are (a) inconsistent with the popular notion that fingerprint evidence is nearly infallible, and (b) larger than error rates reported in leading fingerprint studies. We conclude that, when the risk of CNMs is high, the probative value of a reported fingerprint identification may be severely diminished due to an elevated false‐positive error risk. We call for additional CNM research, including a replication and expansion of the present study using a representative selection of CNMs from database searches.     

When are experiments corrupt?

ABSTRACT

Between 2010 and 2011, the UK’s Department for International Development (DFID) funded a large-scale experiment on Kenyan schools. The policy experiment tested the effects of cutting teachers’ salaries and hiring them on short-term contracts, but the intervention failed after sustained opposition from teacher unions and parent associations. This article critically revisits the narrative of how this experiment was designed, implemented and interpreted, finding evidence that the experiment violated empirical logic. It examines whether the theory of neopatrimonialism can explain the ways in which vested interests may have undermined the empirical logic of the experiment. By doing so, the analysis tests the explanatory utility of neopatrimonialism, and casts light on the conditions under which policy experiments in Africa may be anti-empirical.     

Impinging blood droplets on different wettable surfaces: Impact phenomena,contact line motion,post-impact oscillation and dried stains

Understanding the underlying hydrodynamics of impinging blood droplets and finding out the physical parameters determining the bloodstain characteristics are of great importance in blood related forensic investigations. In this work, the impact of non-Newtonian blood droplets on solid surfaces ranging from lyophilic to superlyophobic was systematically investigated and compared to that of Newtonian droplets with a similar dynamic shear viscosity. We show that impinging blood droplets behave as low-viscosity Newtonian droplets in the short-time spreading, which is dominated by capillary and inertial forces, but their non-Newtonian viscoelasticity would notably affect the droplet retraction and post-impact oscillation occurring in large timescales. Whereas the strong liquid–solid adhesion and the non-Newtonian elongational viscosity hinder droplet recoiling and thus alter the impact phenomena on lyophobic and superlyophobic surfaces, the shear and elongational viscosities are coupled to result in higher damping coefficients of oscillating blood droplets after deposition, in comparison to that of impinging Newtonian droplets. The size of the dried bloodstain was found to be different from both the maximum spreading radius of the droplet that can reach during impact and the final radius of the deposited droplet after oscillation, and their correlations are highly dependent on the impact velocity and surface wettability. Moreover, the morphologic characteristics of the bloodstains would also be changed by varying either the impact velocity or the surface wettability. We envision that these findings can not only find applications in the bloodstain pattern analysis, but also provide useful information for medical diagnosis based on blood droplet test.