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911.
912.
Maíra Kerpel dos Santos PhD Alexander Acosta PhD Ryan Capote BS Bakhtawar Tabassam BS James Ley PhD Martin Quirke PhD José Almirall PhD 《Journal of forensic sciences》2023,68(4):1162-1177
The 4- Aminophenol (4-AP) colorimetric test is a fast, easy-to-use, and cost-effective presumptive assay of cannabis plant material producing different chromophores with THC-rich cannabis (blue color) and with CBD-rich cannabis (pink color). The main drawback of the 4-AP test is a brief observation window where the color rapidly changes to black, limiting the utility of the test. We now report for the first time, the identification of the product chromophores between 4-AP and CBD/THC as well as propose an explanation and a solution for the color degradation of the chromophores. The identification of the chromophores is provided by spectroscopic (UV–Vis), chromatography, and mass spectrometry (TLC and LC-QToF-MS). Oxidation of excess 4-AP (Reagent A) in the presence of NaOH (Reagent B) produces the black color observed for the previously reported 4-AP tests and reported in the literature. The adjustment of reactants concentrations and volumes of 4-AP:THC/CBD to a 1:1 ratio significantly reduces the black oxidation by-product and increases the observation window up to 2 h instead of the previously reported 5–10 min. For the first time, mass spectrometry and chromatography confirmed that the reaction of THC and CBD with 4-AP produced chromophores with m/z (M + H) = 420, consistent with proposed indophenol structures. The TLC method developed confirmed the separation between CBD and THC chromophores. The specificity of the test is also reported, showing false positive results for the presence of THC (blue color) for samples of thyme and oregano. LDA and SIMCA models showed that the optimized 4-AP procedure performs better than the previously reported 4-AP color test. 相似文献
913.
The Effects of Soil Texture on the Ability of Human Remains Detection Dogs to Detect Buried Human Remains
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Michael B. Alexander Ph.D. Theresa K. Hodges Ph.D. Daniel J. Wescott Ph.D. Jacqueline A. Aitkenhead‐Peterson Ph.D. 《Journal of forensic sciences》2016,61(3):649-655
Despite technological advances, human remains detection (HRD) dogs still remain one of the best tools for locating clandestine graves. However, soil texture may affect the escape of decomposition gases and therefore the effectiveness of HDR dogs. Six nationally credentialed HRD dogs (three HRD only and three cross‐trained) were evaluated on novel buried human remains in contrasting soils, a clayey and a sandy soil. Search time and accuracy were compared for the clayey soil and sandy soil to assess odor location difficulty. Sandy soil (p < 0.001) yielded significantly faster trained response times, but no significant differences were found in performance accuracy between soil textures or training method. Results indicate soil texture may be significant factor in odor detection difficulty. Prior knowledge of soil texture and moisture may be useful for search management and planning. Appropriate adjustments to search segment sizes, sweep widths and search time allotment depending on soil texture may optimize successful detection. 相似文献
914.
This article analyses the case law on ombudsman schemes in the UK, with the purpose of identifying some of the key trends that underpin this branch of law pre-the first Supreme Court decision in this area, JR55 v Northern Ireland Commissioner for Complaints. While the law on ombudsman schemes remains based on legislation and the various grounds of administrative law available in judicial review, distinct bespoke principles have also been relied upon. These principles are beginning to provide consistent guidance on how the law should be used and interpreted in cases involving an ombudsman scheme. One task of the Supreme Court in JR55 will be to confirm these principles, or rationalize any departure from them. 相似文献
915.
Signaling and Counter‐Signaling in the Judicial Hierarchy: An Empirical Analysis of En Banc Review
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Deborah Beim Alexander V. Hirsch Jonathan P. Kastellec 《American journal of political science》2016,60(2):490-508
We leverage the institutional features of American courts to evaluate the importance of whistleblowers in hierarchical oversight. Drawing on a formal theory of signaling in the judicial hierarchy, we examine the role of whistleblowing dissents in triggering en banc review of three‐judge panels by full circuits of the Courts of Appeals. The theory generates predictions about how dissent interacts with judicial preferences to influence circuits' review and reversal decisions, which we test using original and existing data. First, we show that judges who dissent counter to their preferences are more likely to see their dissents lead to review and reversal. Second, we show that dissents are most influential when the likelihood of non‐compliance by a three‐judge panel is highest. Our results underscore the importance of dissent in the judicial hierarchy and illustrate how judicial whistleblowers can help appellate courts target the most important cases for review. 相似文献
916.
Field experiments and regression discontinuity designs test whether voting is habit forming by examining whether a random shock to turnout in one election affects participation in subsequent elections. We contribute to this literature by offering a vast amount of new statistical evidence on the long‐term consequences of random and quasi‐random inducements to vote. The behavior of millions of voters confirms the persistence of voter turnout and calls attention to theoretically meaningful nuances in the development and expression of voting habits. We suggest that individuals become habituated to voting in particular types of elections. The degree of persistence appears to vary by electoral context and by the attributes of those who comply with an initial inducement to vote. 相似文献
917.
918.
Albrecht Brian C. Hendrickson Joshua R. Salter Alexander William 《Public Choice》2022,192(1-2):169-188
Public Choice - Politics, like any social system, involves selection mechanisms. This paper presents a model of politics as an evolutionary process. Our model yields three main results. First, the... 相似文献
919.
Bauer A Rosca P Grinshpoon A Khawaled R Mester R Yoffe R Ponizovsky AM 《International journal of law and psychiatry》2007,30(1):60-70
BACKGROUND: Though information about involuntary psychiatric hospitalizations (IPH) is crucial for the planning of Israel's National Mental Health Care Policy, very few studies have been carried out to date on this subject. AIMS: To identify trends in first IPH to all inpatient psychiatric settings in Israel. METHOD: The sample included all admissions of adults (18 years and older) over the ten-year period, 1991-2000, according to the registration of such admissions in the National Psychiatric Case Registry. RESULTS: A 2.4-fold increase was found in first IPH over the decade studied. The typical profile of the involuntarily admitted patient was that of a native-born Jewish male, aged 18-24 or 65 and older, single, with less than 8 years of education, and with a diagnosis of schizophrenia or delusional psychosis. CONCLUSIONS: These findings suggest the need for improving the interfaces between hospital and community services, and for preparing specific guidelines to extend the use of involuntary ambulatory treatment orders. Further study is needed to explore the respective roles of involuntary inpatient and outpatient treatment. 相似文献
920.
Both target effectiveness and administrative simplicity are desirable properties in the design of minimum benefit packages for public retirement programs. The federal benefit rate (FBR) of the Supplemental Security Income (SSI) program has been proposed by some analysts as a potentially attractive basis of establishing a new minimum benefit for Social Security on both of these grounds. This type of proposal is related to a broader array of minimum benefit proposals that would establish a Social Security benefit floor based on the poverty rate. In contrast to Social Security, the SSI program is means tested, including both an income and asset screen and also a categorical eligibility screen (the requirement to qualify as aged or disabled). The SSI FBR provides an inflation-adjusted, guaranteed income floor for aged and disabled people with low assets. The FBR has been perceived by proponents as a minimal measure of Social Security benefit adequacy because it represents a subpoverty income level for a family of one or two depending on marital status. For this same reason it has been seen as a target-effective tool of designing a minimum Social Security benefit. An FBR-based minimum benefit has also been viewed as administratively simple to implement; the benefit can be calculated from Social Security administrative records using a completely automated electronic process. Therefore-in contrast to the SSI program itself-an FBR-based minimum benefit would incur virtually no ongoing administrative costs, would not require a separate application for a means-tested program, and would avoid the perception of welfare stigma. While these ideas have been discussed in the literature and among policymakers in the United States over the years, and similar proposals have been considered or implemented in several foreign countries, there have been no previous analyses measuring the size of the potentially affected beneficiary population. Nor has there been any systematic assessment of the FBR as a measure of benefit adequacy or the tradeoffs between potential target effectiveness and administrative simplicity. Based on a series of simulations, we assess the FBR as a potential foundation for minimum Social Security benefits and we examine the tradeoffs between administrative simplicity and target effectiveness using microdata from the 1996 panel of the Survey of Income and Program Participation (SIPP). Our empirical analysis is limited to Social Security retired-worker beneficiaries aged 65 or older. We start with the assessment of the FBR as a measure of benefit adequacy. We are particularly concerned about two types of error: (1) incorrectly identifying some Social Security beneficiaries as "economically vulnerable," and (2) incorrectly identifying others as "not economically vulnerable." Operationally we measure economic vulnerability by two alternative standards. One of our measures considers beneficiaries with family income below the official poverty threshold as vulnerable. Our second measure is more restrictive; it uses a family income threshold equal to 75 percent of the official poverty threshold. We find that a substantial minority of retired workers have Social Security benefits below the FBR. The results also show that the FBR-based measure of Social Security benefit adequacy is very imprecise in terms of identifying economically vulnerable people. We estimate that the vast majority of beneficiaries with Social Security benefits below the FBR are not economically vulnerable. Conversely, an FBR-level Social Security benefit threshold fails to identify some beneficiaries who are economically vulnerable. Thus an FBR-level minimum benefit would be poorly targeted in terms of both types of errors we are concerned about. An FBR-level minimum benefit would provide minimum Social Security benefits to many people who are clearly not poor. Conversely, an FBR-level minimum benefit would not provide any income relief to some who are poor. The administrative simplicity behind these screening errors also results in additional program cost that may be perceived as substantial. We estimate that an FBR-level minimum benefit would increase aggregate program cost for retired workers aged 65 or older by roughly 2 percent. There are two fundamental reasons for these findings. First, the concept of an FBR-level minimum benefit looks at the individual or married couple in artificial isolation; however, the family is the main consumption unit in our society. The income of an unmarried partner or family members other than a married spouse is ignored. Second, individuals and couples may also have income from sources other than Social Security or SSI, which is also ignored by a simple FBR-based minimum benefit concept. The substantial empirical magnitude of measurement error arising from these conceptual simplifications naturally leads to the assessment of the tradeoff between target effectiveness and administrative simplicity. To facilitate this analysis, we simulate the potential effect of alternative screening methods designed to increase target effectiveness; while reducing program cost, such alternatives also may increase administrative complexity. For example, considering the combined Social Security benefit of a married couple (rather than looking at the husband and wife in isolation) might substantially increase target effectiveness with a relatively small increase in administrative complexity. Adding a family income screen might increase administrative complexity to a greater degree, but also would increase target effectiveness dramatically. The results also suggest that at some point adding new screens-such as a comprehensive asset test-may drastically increase administrative complexity with diminishing returns in terms of increased target effectiveness and reduced program cost. Whether a broad-based minimum benefit concept that is not tied to previous work experience is perceived by policymakers as desirable or not may depend on several factors not addressed in this article. However, to the extent that this type of minimum benefit design is regarded as potentially desirable, the tradeoffs between administrative simplicity and target effectiveness need to be considered. 相似文献