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31.
Testing for drugs in hair raises several difficulties. Among them is the interpretation of the final concentration(s). In a post‐mortem case, analyses revealed the presence of furosemide (12 ng/mL) in femoral blood, although it was not part of the victim's treatment. The prosecutor requested our laboratory to undertake an additional analysis in hair to obtain information about the use of furosemide. A specific method was therefore developed and validated to identify and quantify furosemide in hair by UHPLC‐MS/MS. After decontamination of 30 mg of hair, incubation in acidic condition, extraction with ethyl acetate, the samples were analyzed by UHPLC‐MS/MS. Furosemide was found in the victim's hair at 225 pg/mg. However, it was not possible to interpret this concentration due to the absence of data in the literature. Therefore, the authors performed a controlled study in two parts. In order to establish the basis of interpretation, several volunteers were tested (four after a single 20 mg administration and twenty‐four under daily treatment). The first part indicated that a single dose is not detectable in hair using our method. The second part demonstrated concentrations ranging from 5 to 1110 pg/mg with no correlation between dosage and hair concentrations. The decedent's hair result was interpreted as repeated exposures. In the case of furosemide analysis, hair can provide information about its presence but cannot give information about dosage or frequency of use.  相似文献   
32.
Aluminum (Al) powders are commonly used in improvised explosive devices as metallic fuels, a component of explosive mixtures. These powders can be obtained readily from industrial‐scale and consumer products, and produced using unsophisticated “kitchen chemistry” techniques. This research demonstrates the potential of automated particle micromorphometry for comparisons between known source and questioned Al powders recovered from IEDs, as well as for insight into the method of Al powder manufacture. Al powder samples were obtained from legitimate manufacturers, and 56 samples were produced “in‐house” from Al‐containing spray paints and ball‐milled Al foils. Transmitted light microscope images of Al powder particles were acquired using an automated stage with automated z‐focus; 17 size and shape parameters were measured for all particles. Approximately 37,000–2,500,000 particles/sample were analyzed using an open‐source statistical package with customized code. Dimensionality reduction was required for processing the large datasets: eight of the 17 measured variables were selected based on inspection of the correlation matrix. Data from four subsamples from each of the 56 samples produced using “in‐house” methods were analyzed using ANOVA to assess the within‐ and between‐sample variation. High within‐sample variation was noted; however, ANOVA and post‐hoc Tukey's honestly significant difference (HSD) tests demonstrated that the between‐sample variation was substantially larger than the within‐sample variation. Each sample could be differentiated from all other samples in the test set. Future experiments will focus on ways to reduce the within‐sample variation, and additional statistical and microanalytical methods to classify sources and confidently constrain the method of Al powder manufacture.  相似文献   
33.
This study examines the influence of three-layered cranial architecture development upon blunt force trauma (BFT) cranial outcomes associated with pediatric non-accidental injury (NAI). Macroscopic and microscopic metric and morphological comparisons of subadult crania ranging from perinatal to 17 years of age chronicle the ontogenetic development and spatial and temporal variability in the emergence of a mature cranial architecture. Cranial vault thickness increases with subadult age, accelerating in the first 2 years of life due to rapid brain growth during this period. Three-layer differentiation of the cranial tables and diploë initiates by 3–6 months but is not consistently observed until 18 months to 2 years; diploë formation is not well developed until after age 4 and does not manifest a mature appearance until after age 8. These results allow topographic documentation of cortical and diploic development and temporal and spatial variability across the growing cranium. The lateral cranial vault is identified as expressing delayed development and reduced expression of the three-layer architecture, a pattern that continues into adulthood. Comparison of fracture locations from known BFT pediatric cases with identified cranial fracture high-risk impact regions shows a concordance and suggests the presence of a higher fracture risk associated with non-accidental BFT in the lateral vault region in subadults below the age of 2. The absence or lesser development of a three-layered architecture in subadults leaves their cranial bones, particularly in the lateral vault, thin and vulnerable to the effects of BFT.  相似文献   
34.
The presence of diatom algae in bone marrow has been used as forensic evidence of drowning for several decades; however, these studies are based on known or suspected recent drowning events. This study addresses the potential for diatoms to enter the bone marrow of skeletal remains, that is, de-fleshed long bones post-mortem. In laboratory and field experiments, bones were either inflicted with two access points by a cut and acid pitting or left intact. The bones were submerged in water for at least 1 week and up to 3 months. Samples of the bone surface and marrow were inspected for diatoms. The analysis considered the time required for diatoms to enter marrow and whether genus characteristics like size or mobility affect entry. The presence of an access point influenced diatom entry in that bones without an introduced access point had zero to one diatom present in the marrow, whereas a bone with an access point had >150 diatoms present in the marrow. The results of both laboratory and field phases suggest that diatoms will reliably colonize bone in as quickly as 1 week, establishing and maintaining communities for at least 3 months. However, the bone surface assemblages differ from the source community. Bone marrow displayed even more restrictive access to diatom colonization, resulting in communities dominated by small raphid diatoms. Based on these findings, we suggest some caveats on the use of diatoms as trace evidence in forensic science with recommendations for future avenues of research.  相似文献   
35.
This exploratory study examined juvenile drug courts’ effect on adulthood recidivism. Utilizing a twelve-year average follow up time, adult recidivism rates were compared between previous juvenile drug court participants and a comparison group of juveniles who participated in traditional probation. Linear regression models indicated limited recidivism effects of drug court on arrests or convictions into adulthood. The findings suggest that gender and race may play a role in how justice-involved juveniles interact and experience juvenile drug court, highlighting the need for gender-responsive and culturally responsive policies, practices, and programs within juvenile drug courts. Recommendations are made regarding future research areas and ways to potentially improve long-term juvenile drug court outcomes.  相似文献   
36.
Using a sample of 20,000 adolescents (Add Health data), this study examined the influences of community poverty and race/ethnicity on adolescent obesity. Multilevel analyses revealed strong evidence for the unique influences of community poverty and race/ethnicity on adolescent obesity net of family characteristics. The prevalence of obesity is significantly higher in poor communities than in affluent communities; and it is higher among African Americans, Hispanics and Native Americans than among Whites. The interaction between race/ethnicity and community poverty indicates that race/ethnicity moderates the influence of community poverty on the prevalence of obesity. Although the prevalence of obesity is higher among minorities than among Whites, the influence of community poverty is stronger for Whites than for minorities, suggesting that unlike Whites, most minority groups may not accrue benefits of structural community advantages. The state of being overweight as the outcome variable provided essentially the same findings. The practical implications are discussed.  相似文献   
37.
In this study, we investigated time-dependent expression of matrix metalloproteases (MMP)-2, MMP-9, chemokine CC motif ligand (CCL)-2, CCL-3, CCL-5, IL-1β, IL-6, and TNF-α mRNA at the skin injury site and sought their forensic potentials during the skin wound repair process. The tested wound ages in 42 mouse skin wounds were distributed at 0d, 1d, 3d, 5d, 7d, 10d, and 14d, respectively and then followed by real-time polymerase chain reaction. Ultimately, MMP-2 played an important role in the inflammation phase. On the contrary, MMP-9 became involved at a later phase during wound healing. Meanwhile, CCL-2 and CCL-3 were active throughout almost all of the process. However, CCL-5 mRNA had no significance. Collectively, an MMP-9/MMP-2 ratio of over 0.84 indicated that skin wound healing age was strongly 5 days or less. So elevated gene expressions of cytokines and chemokines in different phases of wound ages implied that combined exploration could make wound age determination more accurate and objective.  相似文献   
38.
Fentanyl, fentanyl analogs, and other novel synthetic opioids (NSO), including nitazene analogs, prevail in forensic toxicology casework. Analytical methods for identifying these drugs in biological specimens need to be robust, sensitive, and specific. Isomers, new analogs, and slight differences in structural modifications necessitate the use of high-resolution mass spectrometry (HRMS), especially as a non-targeted screening method designed to detect newly emerging drugs. Traditional forensic toxicology workflows, such as immunoassay and gas chromatography mass spectrometry (GC–MS), are generally not sensitive enough for detection of NSOs due to observed low (sub-μg/L) concentrations. For this review, the authors tabulated, reviewed, and summarized analytical methods from 2010–2022 for screening and quantification of fentanyl analogs and other NSOs in biological specimens using a variety of different instruments and sample preparation approaches. Limits of detection or quantification for 105 methods were included and compared to published standards and guidelines for suggested scope and sensitivity in forensic toxicology casework. Methods were summarized by instrument for screening and quantitative methods for fentanyl analogs and for nitazenes and other NSO. Toxicological testing for fentanyl analogs and NSOs is increasingly and most commonly being conducted using a variety of liquid chromatography mass spectrometry (LC–MS)-based techniques. Most of the recent analytical methods reviewed exhibited limits of detection well below 1 μg/L to detect low concentrations of increasingly potent drugs. In addition, it was observed that most newly developed methods are now using smaller sample volumes which is achievable due to the sensitivity increase gained by new technology and new instrumentation.  相似文献   
39.
The post-attendee Uniform Resource Locator (URL) feature within the video conferencing application known as Zoom is often overlooked by digital forensic experts as a potential risk for malware transmission. However, with the ability to redirect webinar participants to any URL set by the host for the webinar, the post-attendee URL can be abused by bad actors to expose webinar participants to malicious websites or, in the worst-case scenario, force participants to download a file through the use of a direct download link URL. This study aims to showcase how this exploit can be replicated by creating an experimental environment involving four Windows 10 desktops running Zoom version 5.7.5 and creating a webinar with four user accounts acting as webinar participants and setting the post-attendee URL value to the URL of a website that contained a keylogger. In another trial, the same experimental environment was utilized, with the only difference being the post-attendee URL that was set to redirect webinar participants to a download link for a .jpg file. In both instances, every user account that joined the webinar via clicking on the invitation link that was emailed to each user account after registering for the webinar was redirected to the post-attendee URL regardless of their user account role. These results not only prove that the post-attendee URL can be exploited, but also provide insight as to how this type of attack can be prevented.  相似文献   
40.
Forensic science practitioners are often called upon to attribute crimes using trace evidence, such as explosive remnants, with the ultimate goal of associating a crime with a suspect or suspects in order to prevent further attacks. The explosive charge is an attractive component for attribution in crimes involving explosives as there are limited pathways for acquisition. However, there is currently no capability to link an explosive charge to its source via post-blast trace residues using isotope ratios or trace elements. Here, we sought to determine if pre-blast attribution signatures are preserved after detonation and can be subsequently recovered and detected. A field study was conducted to recover samples of post-blast explosives from controlled detonations of ammonium nitrate-aluminum (AN-Al), which were then analyzed via isotope ratio mass spectrometry (IRMS) and inductively coupled plasma-mass spectrometry (ICP-MS) for quantitation and profiling of isotopes ratio and trace element signatures, respectively. Oxygen and nitrogen isotope ratios from AN-Al yielded some of the most promising results with considerable overlap within one standard deviation of the reference between the spreads of pre- and post-blast data. Trace element results from AN-Al support the findings in the isotope ratio data, with 26 elements detected in both pre- and post-blast samples, and several elements including B, Cd, Cr, Ni, Sn, V, and Zn showing considerable overlap. These preliminary results provide a proof-of-concept for the development of forensic examinations that can attribute signatures from post-blast debris to signatures in pre-blast explosive materials for use in future investigations.  相似文献   
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