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441.
Parent-adolescent conflict is viewed as a common dimension of the family during the teenage years. The purpose of the present study was to determine whether mothers and fathers of young adolescents differ in their report of conflict with their adolescent, level of stress, and parenting competence. Furthermore, the role of age and gender of the young adolescents was examined. One hundred and twenty-two adolescents and their parents participated in the study. All families were intact. The families were divided into groups according to the adolescent's age and gender. Analyses of variance with three factors (adolescent's age, adolescent's gender, mothers versus fathers) were performed. Mothers and fathers did not differ on personal (depression) or marital adjustment and on perceived parenting competency. In contrast, in terms of parent-adolescent conflict, mothers reported a less positive relationship, a greater number of conflicts, and more intense discussions of conflicts with their adolescents. Gender and age of the adolescent were not important contributors to the analyses. The results suggest that, in terms of the variables examined in this study, conflict in the parent-adolescent relationship is the primary difference between mothers and fathers.  相似文献   
442.
Measurements of the type and concentration of propellant and stabilizer additives in smokeless gunpowder are used by forensic scientists investigating the source of explosives and by military laboratories assuring the safety and efficacy of munitions. The National Institute of Standards and Technology recently assessed the state-of-the-practice of smokeless powder measurements through an international measurement comparison exercise. We here present results provided by the five participants (of 20 total) reporting quantitative as well as qualitative values for two handgun reloading powders. All five of these participants reported values for nitroglycerin (NG), ethyl centralite (EC), diphenylamine (DPA), and N-nitrosodiphenylamine (NnDPA). Several participants additionally reported the concentrations of secondary stabilizer decomposition products. The unstable NG propellant additive appears to be more susceptible to method-specific calibration biases then are the stabilizer additives. All results from one participant were strongly biased relative to those of the other four. The within-participant measurement uncertainties for all analytes were self-reported to be 1 to 5% relative; among the four concordant participants, the measurement ranges are 5 to 10% relative. There was little consistency among the participants as to what components of measurement variance were included in their uncertainty statements. A discussion of the certainties in these measurements and factors that affect the accuracy of gunpowder additive determinations is presented.  相似文献   
443.
A 26‐year‐old Caucasian sailor, with no past medical history aside from headache for the last 1 week, was found dead in his cabin. The body was stored in a refrigerator on board and disembarked for autopsy 3 days later. Autopsy showed a large, nodular, necrotic and hemorrhagic retroperitoneal mass, and smaller hemorrhagic nodules in the brain, lungs, liver, and left kidney, with the brain being markedly edematous. Both testes were descended and normal. Histologically, the retroperitoneal mass showed a malignant mixed germ cell tumor comprising choriocarcinoma, embryonal carcinoma, and teratoma components. Retroperitoneal extragonadal germ cell tumors are uncommon, and this case of a young male who presented with headache and sudden death due to metastases is extremely rare.  相似文献   
444.
445.
In forensic science, scientific problem-solving is characterized by the recognition of traces as part of iterative reasoning processes to assign meaning to those traces in order to interpret and reconstruct events. Through a set of fundamental principles, the Sydney Declaration presents a foundation of forensic science through the lens of a scientist. The distinction between a scientist and a technician may require clarification—where a prototypical technician follows a prescribed set of ‘standard operating procedures’ and may be limited in the interpretation of the resultant data, the scientist utilizes knowledge, skills, experience and imagination to identify the issue at hand and develop lines of inquiry for testing and interpretation. This case report draws on the Sydney Declaration in order to highlight the importance of learning about events from careful consideration of both obvious and less obvious traces. A case involving the assault of a police officer is examined to illustrate the use of the Principles: the problem originally defined by investigators at the scene and later by prosecutors resulted in incorrect analysis and interpretation of traces, hampering efforts at an accurate reconstruction of events. This exercise serves to demonstrate that in order to engage in scientific problem-solving, it is necessary to apply observation and reasoning in forensic investigations in order to yield an outcome that can be clearly articulated. The overarching goal is to support the drive to improve forensic science practice, education, and research through a case illustrating the value of the principles of the Sydney Declaration.  相似文献   
446.
Using administrative data from Maine to quantify the effect of vocational rehabilitation (VR) services on employment outcomes for transition-age youth with disabilities, we exploited the variation in VR counselors’ propensity to develop Individualized Plans for Employment (IPEs) for VR youth as an instrument for service receipt. We found that among the estimated 36 percent of VR clients on the margin of service receipt, having an IPE implemented increases quarterly employment rate by 15.4 percentage points and quarterly earnings by $1,442 (2018 dollars). We found heterogeneous program effects with individuals 18 or younger benefiting significantly more than those older than age 18 at the time of VR application. We estimate the annual real rate of return to be 10.2 percent for two years after VR case closure.  相似文献   
447.
Cartridge cases may contain deposited fingermarks when the firearm was loaded ( http://www.nij.gov/pubs-sum/225320.htm , J Forensic Sci, 53 , 2008 and 812). Cartridge cases can be individualized with microscopic examination. However, heat and friction degrades the deposited fingermark on the fired cartridge cases, if any on the surface. Also, unfired and fired cartridge cases are made of metal, which is a nonporous surface that does not retain fingermarks well ( http://www.nij.gov/pubs-sum/225320.htm ). This study tests the effects of pH level on fingermark clarity on brass fired and unfired cartridge cases and microscopic striation examination (MSE). Two trials were performed to determine the optimal pH in fingermark clarity for both types of cartridges. This was performed through immersion in six pH range solutions from dilutions of sulfuric acid and sodium hydroxide for 24 h for the purpose of enhancing the fingermarks on the metal. The use of the optimal neutral pH level is suggested because immersion of the cartridge cases in pH 1–3 and 3–5 affects MSE.  相似文献   
448.
Medical examiners and coroners (ME/C) in the United States hold statutory responsibility to identify deceased individuals who fall under their jurisdiction. The computer‐assisted decedent identification (CADI) project was designed to modify software used in diagnosis and treatment of spinal injuries into a mathematically validated tool for ME/C identification of fleshed decedents. CADI software analyzes the shapes of targeted vertebral bodies imaged in an array of standard radiographs and quantifies the likelihood that any two of the radiographs contain matching vertebral bodies. Six validation tests measured the repeatability, reliability, and sensitivity of the method, and the effects of age, sex, and number of radiographs in array composition. CADI returned a 92–100% success rate in identifying the true matching pair of vertebrae within arrays of five to 30 radiographs. Further development of CADI is expected to produce a novel identification method for use in ME/C offices that is reliable, timely, and cost‐effective.  相似文献   
449.
This paper reviews the current state of the housing market, particularly in the shadow of the foreclosure crisis, the collapse of the financial system, and persistent unemployment. The authors outline the policy priorities necessary to facilitate the recovery of the housing market in general and to encourage comprehensive revitalization of the hardest hit communities.  相似文献   
450.
While the reasons for the failure of the groundnut scheme are well understood, its effects on colonial development in Tanganyika are not. Drawing from the voluminous paper trail that development planning leaves in its wake, this paper traces the effects of the groundnut scheme demise on a contemporaneous plan to build a railway across Tanganyika to the Northern Rhodesian copperbelt. Tensions arose among the railway planners – civil servants, politicians, and consultants from Britain, Africa, and the United States – when, midway through the planning process, the scale of the groundnut scheme collapse became public. I demonstrate how this revealing crisis prompted planners to eschew the project's production-oriented impetus and embrace a welfare-oriented conclusion. By demonstrating the interlinked nature of development projects, this paper proposes a new angle for studying the history of development in an era characterised by the rapid proliferation of projects.  相似文献   
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