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51.
Optical tweezers have a wide range of uses for mechanical manipulation of objects in the microscopic range. This includes both living and static cells in a variety of biomedical and research applications. Single-focus optical tweezers, formed by focusing a laser beam through a high numerical aperture immersion objective, create a significant force, which enables controlled transport of a variety of different cell types and morphologies in three dimensions. Optical tweezers have been previously reported to capture and separate spermatozoa from a reconstituted simulated postcoital sample. We report herein the development of a simplified, more efficient cell transfer protocol that can separate and isolate both spermatozoa as well as leukocytes, with similar efficiencies as those previously reported. The new cell transfer method was used to separate sperm cells from a reconstituted mixture of spermatozoa and vaginal epithelial cells, with complete STR profiles developed from 50 cells with little evidence of contribution from the female contributor to the mixture. This modified protocol was then used to separate 21 samples of enriched leukocytes, with trapped cells ranging from 5 to 22 cells. Complete STR profiles were developed from as few as 10 leukocytes. Thus, with minimal sample preparation and a short trapping time, this method has the potential to provide an alternative to traditional differential extraction methods for separation of sperm:nonsperm mixtures while also providing versatility for separation of cells with differing morphologies.  相似文献   
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Abstract

The outside world is well aware of the totalitarian side of North Korea. Much less well-known is the shadow economy of the country which has enveloped the everyday lives of ordinary North Koreans for the last fifteen years or so. Based on refugee testimonies, this article aims to shed light on this heretofore unexamined aspect of the country, by visualizing the invisible hands of the ever-growing shadow economy in North Korea. In particular, we will investigate who the main actors are (the agency question), how they obtain their items (the supply mechanism), how they move items from one place to another (the distribution mechanism) and who consumes these items (the consumer question) in contemporary North Korean society.  相似文献   
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We have developed a technique that allows investigators to confirm the presence of blood, semen, and/or saliva in a crime scene sample. It is a confirmatory test where multiple samples can be processed in less than an hour, and it is potentially portable, permitting samples to be processed at the crime scene. Samples at a scene giving a positive result can be further processed while those failing to do so may be ignored. There is a large and growing backlog of DNA evidence in the USA, slowing down the criminal justice system. This backlog has continued to grow despite an increase in the ability to process evidence faster. This technique uses quantum dot molecular beacons to test for tissue‐specific RNA species, identifying particular body fluids. We have demonstrated the tissue specificity of molecular beacons for blood, semen, and saliva.  相似文献   
55.
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   
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Seat-belt injuries to the neck in a traffic accident or any trauma to the neck in other situations can cause tearing of the inner surface of the carotid arteries and lead to the formation of a fresh thrombus, or can cause partial to complete transection of the carotid arteries.  相似文献   
58.
Latent fingerprints were successfully visualized using fluorescence lifetime imaging (FLIM) on paper which emits strong fluorescence with a lifetime close to that of fingerprints and thus from which it is difficult for time-resolved spectroscopy to visualize fingerprints. Latent fingerprint samples on paper were excited using a 450 nm or 532 nm nanosecond pulsed-laser, and time-resolved fluorescence images were obtained at a delay time of 6–16 ns in intervals of 1 ns, to the excitation pulse. The excitation beam was expanded using a lens, and the fluorescence from the fingerprints was captured using an intensified CCD camera. Because of the large fluorescence intensity of the background paper of approximately two to four orders of magnitude larger than that of the fingerprint, the fingerprint was not visualized on each fluorescence image by time-resolved spectroscopy. However, the fingerprint was visualized in a FLIM image constructed using a series of the fluorescence images for the case with the fluorescence intensity of the background paper being four orders of magnitude larger than that of the fingerprint. The difference in fluorescence lifetime in the FLIM image of the visualized fingerprint and background paper was in the order of 0.1 ns, which was an order of magnitude smaller than the inherent fluorescence lifetime of a few nanoseconds for the fingerprints and paper. It was demonstrated that, at a background fluorescence intensity with a certain order of magnitude larger than that of fingerprints, FLIM has the potential to visualize latent fingerprints which cannot be visualized by time-resolved spectroscopy.  相似文献   
59.
One of Indonesia characters is welfare state, reflected in Republic Indonesia Constitution in 1945 (UUD NRI year 1945) on Preamble paragraph 4 mentioning the general welfare is the primary aim of the state. Provision of Article 33 paragraph (2), (3), and (4) UUD NRI year 1945 as lives of many people that natural resources inform of water for the greatest prosperity of people's and controlled by state. This is in line with the Constitution Act No. 7 year 2004 on water resources, focus on welfare of people and based on the reflection of democracy spirit. Based on the constitution of Local Government Act No. 32 year 2004, the important role to support the achievement of social welfare problems associated with water (ground water), is crucial. However, the Presidential Decree RI No. 36 year 2010 which provides space for the foreigners to invest in water exploitation orientation, and there was interest~politic of law, so the local government at the beginning prioritize on the welfare of the local people turned into the realm of economic interest to revenue for local government. Based on the statement above, so the problems of people's welfare, democracy and justice are neglected.  相似文献   
60.
In the past, pattern disciplines within forensic science have periodically faced criticism due to their subjective and qualitative nature and the perceived absence of research evaluating and supporting the foundations of their practices. Recently, however, forensic scientists and researchers in the field of pattern evidence analysis have developed and published approaches that are more quantitative, objective, and data driven. This effort includes automation, algorithms, and measurement sciences, with the end goal of enabling conclusions to be informed by quantitative models. Before employing these tools, forensic evidence must be digitized in a way that adequately balances high-quality detail and content capture with minimal background noise imparted by the selected technique. While the current work describes the process of optimizing a method to digitize physical documentary evidence for use in semi-automated trash mark examinations, it could be applied to assist other disciplines where the digitization of physical items of evidence is prevalent. For trash mark examinations specifically, it was found that high-resolution photography provided optimal digital versions of evidentiary items when compared to high-resolution scanning.  相似文献   
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