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121.
This article provides a practical guide for improving the quality of evidence‐based policy. Rather than adopting an approach that gives priority to particular types of research methodologies, this paper argues that evidence drawn from any methodology will improve if standards of transparency and accountability are followed in the process of gathering, analysing, interpreting, and presenting evidence for policy. The papers details what these standards of transparency and accountability mean in practice, how these standards can be achieved, and possible limits to their adoption.  相似文献   
122.
Several nondestructive and semidestructive analyses were used to discriminate colorless transparent polyethylene bags. Transparent plastic bags made from low-density and linear low-density polyethylene usually contain antiblocking agents to prevent sticking of the film, which makes it difficult to open the mouths of plastic bags. Inorganic antiblocking agents are uniformly dispersed in polyethylene films, so they are easily observed using optical microscopy. The particle size distributions of the antiblocking agents were compared by statistical tests. Particle composition was examined by elemental analysis using energy-dispersive X-ray spectrometry with a scanning electron microscope and by molecular vibration analysis using a sensitive microscopic Raman spectrometer. The compositions could be determined nondestructively on the basis of the results. These data reinforce the morphological discrimination. Morphological discrimination of the dispersed antiblocking agent powders, statistical comparison of particle size distributions, and compositional analysis of the antiblocking agents strengthen the ability to discriminate polyethylene films.  相似文献   
123.
Each digital camera has an intrinsic fingerprint that is unique to each camera. This device fingerprint can be extracted from an image and can be compared with a reference device fingerprint to determine the device origin. The complexity of the filters proposed to accomplish this is increasing. In this note, we use a relatively simple algorithm to extract the sensor noise from images. It has the advantages of being easy to implement and parallelize, and working faster than the wavelet filter that is common for this application. In addition, we compare the performance with a simple median filter and assess whether a previously proposed fingerprint enhancement technique improves results. Experiments are performed on approximately 7500 images originating from 69 cameras, and the results are compared with this often used wavelet filter. Despite the simplicity of the proposed method, the performance exceeds the common wavelet filter and reduces the time needed for the extraction.  相似文献   
124.
Abstract: The chemical profiling of illicit drugs is an important analytical tool to support the work of investigating and law enforcement authorities. In our work, comprehensive two‐dimensional gas chromatography–time‐of‐flight mass spectrometry (GC × GC‐TOFMS) combined with nontargeted, pixel‐based data analysis was adapted for the chemical profiling of 3,4‐methylenedioxymethamphetamine (MDMA). The validity and benefit of this approach was evaluated by analyzing a well‐investigated set of MDMA samples. Samples were prepared according to a harmonized extraction protocol to ensure the comparability of the chemical signatures. The nontargeted approach comprises preprocessing followed by analysis of variances as a fast filter algorithm for selection of a variable subset followed by partial least squares discriminant analysis for reduction to promising marker compounds for discrimination of the samples according to their chemical profile. Forty‐seven potential marker compounds were determined, covering most of the target impurities known from the harmonized one‐dimensional profiling as well as other compounds not previously elucidated.  相似文献   
125.
In Europe, authorities frequently ask forensic laboratories to analyze seized cannabis plants to prove that cultivation was illegal (drug type and not fiber type). This is generally done with mature and flowering plants. However, authorities are often confronted with very young specimens. The aim of our study was to evaluate when the chemotype of cannabis plantlets can be surely determined through analysis of eight major cannabinoids content during growth. Drug-type seedlings and cuttings were cultivated, sampled each week, and analyzed by high-performance liquid chromatography with diode array detection. The chemotype of clones was recognizable at any developmental stage because of high total Δ(9)-tetrahydrocannabinol (THC) concentrations even at the start of the cultivation. Conversely, right after germination seedlings contained a low total THC content, but it increased quickly with plant age up, allowing chemotype determination after 3 weeks. In conclusion, it is not necessary to wait for plants' flowering to identify drug-type cannabis generally cultivated in Europe.  相似文献   
126.
Lip prints are thought to have the ability to distinguish individuals and, hence, have a potential use in human identification purposes. However, questions remain regarding their utility for sex determination. This study aimed to classify lip prints for different individuals in a Portuguese population and to determine whether sex differences exist. Lip prints of 25 females and 25 males were obtained using dark-colored lipstick and cellophane tape. Lip prints were analyzed using a magnifying lens and classified according to the Suzuki and Tsuchihashi classification. A Type II pattern was found to be most common. A comparison of lip-print patterns between males and females showed results with a statistically significant difference: Type III pattern was most common in males, and a Type II pattern in females. This study corroborates the hypothesis that lip prints are able to distinguish individuals and may be useful in sex determination.  相似文献   
127.
Acid scavengers are frequently used as stabilizer compounds in a variety of applications. When used to stabilize volatile compounds such as nerve agents, the lower volatility and higher stability of acid scavengers make them more persistent in a post-event forensic setting. Compound-specific isotope analysis of carbon, nitrogen, and hydrogen in three acid-scavenging compounds (N,N-diethylaniline, tributylamine, and triethylamine) were used as a tool for distinguishing between different samples. Combined analysis of multiple isotopes improved sample resolution, for instance differentiation between triethylamine samples improved from 80% based on carbon alone to 96% when combining with additional isotope data. The compound-specific methods developed here can be applied to instances where these compounds are not pure, such as when mixed with an agent or when found as a residue. Effective sample matching can be crucial for linking compounds at multiple event sites or linking a supply inventory to an event.  相似文献   
128.
The Supreme Court's unanimous decision in Belmont Park Investments Pty Ltd v BNY Corporate Trustee Services Ltd and Lehman Brothers Special Financing Inc is of major significance to lenders, especially those in the global structured finance market. This case confirms the validity of commonly used insolvency‐triggered secured‐priority flip clauses, and, more generally, suggests a dramatically reduced role for the common law anti‐deprivation principle. The decision may not fully resolve market uncertainty, however, given the particular analysis adopted in the case itself (analysed here) and its divergence from the US statutory approach to the same principle.  相似文献   
129.
U.S. citizens who marry foreign nationals may petition for their spouses so that the couple can reside permanently together in the United States. The guidelines set forth in the U.S. Citizenship and Immigration Services Adjudicator's Field Manual provide guidance to immigration officials for determining whether to grant or deny spousal petitions. Previously, the Adjudicator's Field Manual imposed a requirement that transgender individuals undergo costly and dangerous sex reassignment surgery in order to qualify as married for the purposes of a spousal petition. However, revisions to the Adjudicator's Field Manual issued in April 2012 provide transgender binational couples the opportunity to remain together in the United States without forcing one partner to undergo sex reassignment surgery. Given the history of discrimination against transgender individuals under U.S. immigration law, these revisions are a significant step in equality for transgender couples. Although these revisions provide many transgender binational couples with a means to remain together in the United States, this Note proposes that, to continue on the path toward equality for transgender couples, special guidelines should not be applied to marriages involving transgender partners if their marriage is deemed a valid heterosexual marriage in the state where solemnized. The goals of U.S. immigration law and compliance with the federal definition of marriage can be achieved without implementing individualized guidelines for transgender binational couples.
    Key Points for the Family Court Community:
  • Transgender spouses of a binational couple should not be subjected to additional guidelines when submitting spousal petitions that, if granted, would afford the couple the opportunity to reside together in the United States
  • Transgender individuals should not be subjected to disparate treatment solely because the U.S. Citizenship and Immigration Services seeks to enforce discriminatory provisions of the Defense of Marriage Act
  • A marriage should be recognized by immigration law if it is a valid marriage under the law of the state where the marriage was celebrated
  • In order to achieve U.S. immigration law's mission of family unification, nontraditional couples should be afforded the same opportunity to remain together in the United States without additional scrutiny
  相似文献   
130.
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