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861.
A collaborative study on Raman spectroscopy and microspectrophotometry (MSP) was carried out by members of the ENFSI (European Network of Forensic Science Institutes) European Fibres Group (EFG) on different dyed cotton fabrics. The detection limits of the two methods were tested on two cotton sets with a dye concentration ranging from 0.5 to 0.005% (w/w). This survey shows that it is possible to detect the presence of dye in fibres with concentrations below that detectable by the traditional methods of light microscopy and microspectrophotometry (MSP). The MSP detection limit for the dyes used in this study was found to be a concentration of 0.5% (w/w). At this concentration, the fibres appear colourless with light microscopy. Raman spectroscopy clearly shows a higher potential to detect concentrations of dyes as low as 0.05% for the yellow dye RY145 and 0.005% for the blue dye RB221. This detection limit was found to depend both on the chemical composition of the dye itself and on the analytical conditions, particularly the laser wavelength. Furthermore, analysis of binary mixtures of dyes showed that while the minor dye was detected at 1.5% (w/w) (30% of the total dye concentration) using microspectrophotometry, it was detected at a level as low as 0.05% (w/w) (10% of the total dye concentration) using Raman spectroscopy. This work also highlights the importance of a flexible Raman instrument equipped with several lasers at different wavelengths for the analysis of dyed fibres. The operator and the set up of the analytical conditions are also of prime importance in order to obtain high quality spectra. Changing the laser wavelength is important to detect different dyes in a mixture.  相似文献   
862.
Rapport is an important part of the interviewing of suspects, enabling them to supply information more freely. This study examined 142 actual interviews with suspects, focussing on key tasks that aid rapport. Using an established framework to examine rapport building skills in the early stages of interviews, the study also measured how skilled attempts at sustaining rapport were when interviewers attempted to gather information from suspects and probe accounts for their reliability. It was found that opportunities were often missed to build rapport in the initial stages as several tasks were overlooked. Also, where any rapport had been initially built, it was not always maintained as tasks undertaken later in the interview which may well have assisted rapport maintenance were often conducted unsatisfactorily. Thus, initial rapport building of itself, therefore, is not sufficient in influencing overall interview quality and outcomes, since rapport also has to be maintained throughout the interview.  相似文献   
863.
Despite developments in police psychology in North America and Europe, little is known about developments in other parts of the world. Yet, this knowledge will reinforce the development of the field of police psychology internationally and strengthen its scientific theories, practices and programs. This paper therefore traces the development of police psychology in Singapore for over two decades across four waves of development. This paper also describes the developments in three areas of police psychology (services to police officers, police operations and the police organization) and details the various police psychological services programs and services in Singapore. The paper concludes with a discussion on strategic concerns for police psychologists worldwide, arguing that there is a need to discuss the ‘what works, when and where?’ in police psychology, when it is applied across the world.  相似文献   
864.
Prior research has provided substantial evidence that child maltreatment and exposure to physical intimate partner violence (IPV) are associated with increased externalizing behavior problems among children and adolescents. However, little is known about the effects of exposure to psychological IPV and exposure to the physical abuse of a sibling. Using a total sample (N = 2,572) and subsample (n = 441) of children ages 3–18 years old, the purpose of this study was to assess whether cumulative types of family violence lead to higher mean externalizing behavior scores and to examine the effects of single types of indirect and direct family violence on children’s mean externalizing behavior scores. Results confirmed that children who experienced any type of family violence victimization had higher mean externalizing behavior scores compared to children with no history of family violence; however, few differences in externalizing behavior scores were found as the number of family violence types increased. Children who experienced indirect types of family violence (e.g., exposure to the physical abuse of a sibling) had higher externalizing behavior scores than children who experienced direct maltreatment (e.g., child physical abuse). Findings from this study suggest that researchers and service providers should adopt a broader conceptualization of family violence victimization and increase the amount of services provided to children who are indirectly victimized.  相似文献   
865.
Limited information is available about the international generalizability of the common conclusion that marital discord tends to be associated with problematic parenting. Pakistan is a sociocultural context known for a high frequency of marital distress. Accordingly, this study draws from a sample of 270 Pakistani families with children between the ages of 9 to 13 years (M?=?11.21 years). In this study we explore the question: Are Pakistani children’s perceptions of maternal and/or paternal rejection related to their parents’ perceptions of spousal rejection? Results of a hierarchical multiple regression analyses showed that wives’ perceptions of husbands’ rejection predicted children’s perceptions of maternal rejection, as well as—but to a significantly lesser extent—children’s perceptions of paternal rejection. Similarly, husbands’ perceptions of wives’ rejection predicted children’s perceptions of paternal rejection, as well as—but to a significantly lesser extent—children’s perceptions of maternal rejection. Results of this research, along with the slim body of prior international research, suggests that the concept of “spillover effect” used to explain the association between spousal rejection and parental rejection may have widespread international applicability.  相似文献   
866.
Despite financial innovations that have created important new substitutes for cash usage, per capita holdings of U.S. currency amount to $2950. Yet American households and businesses admit to holding only 15% of the currency stock, leaving the whereabouts of 85% unknown. Some fraction of this unaccounted for currency is held abroad (the dollarization hypothesis) and some is held domestically undeclared, as a store of value and a medium of exchange for transactions involving the production and distribution of illegal goods and services, and for transactions earning income that is not reported to the IRS (the unreported economy hypothesis). We find that the percentage of U.S. currency currently held overseas is between 30 and 37% rather than the widely cited figure of 65%. This finding is based on the official Federal Reserve/Bureau of Economic Analysis data which is a proxy measure of the New York Federal Reserve’s (NYB) “confidential” data on wholesale currency shipments abroad. We recommend that the NYB data be aggregated so as to circumvent confidentiality concerns, and be made readily available to all researchers in order to shed greater light on the questions of how much U.S. currency is abroad and on the particular location of overseas U.S. dollars. The newly revised official estimates of overseas currency holdings are employed to determine the Federal Reserve’s seigniorage earnings from 1964–2010, which have provided a $2950. Yet American households and businesses admit to holding only 15% of the currency stock, leaving the whereabouts of 85% unknown. Some fraction of this unaccounted for currency is held abroad (the dollarization hypothesis) and some is held domestically undeclared, as a store of value and a medium of exchange for transactions involving the production and distribution of illegal goods and services, and for transactions earning income that is not reported to the IRS (the unreported economy hypothesis). We find that the percentage of U.S. currency currently held overseas is between 30 and 37% rather than the widely cited figure of 65%. This finding is based on the official Federal Reserve/Bureau of Economic Analysis data which is a proxy measure of the New York Federal Reserve’s (NYB) “confidential” data on wholesale currency shipments abroad. We recommend that the NYB data be aggregated so as to circumvent confidentiality concerns, and be made readily available to all researchers in order to shed greater light on the questions of how much U.S. currency is abroad and on the particular location of overseas U.S. dollars. The newly revised official estimates of overseas currency holdings are employed to determine the Federal Reserve’s seigniorage earnings from 1964–2010, which have provided a 287 billion windfall for U.S. taxpayers. Overseas currency stock data are also used to derive estimates of the domestically held stock of currency as well as narrow and broad measures of domestic monetary aggregates. These domestic monetary aggregates are believed to be better predictors of future economic activity than traditional monetary aggregates and are tested to determine their ability to predict fluctuations in real output and prices. Domestic cash holdings are finally used to estimate the size of the U.S. unreported economy as measured by the amount of income that is not properly reported to the IRS. By 2010, we estimate that legal and illegal source unreported income” is $1.9–$1.9–2.4 trillion, implying a “tax gap” in the range of $400–$400–540 billion. Currently, we estimate that 18–23% of total reportable income is not properly reported to the IRS.  相似文献   
867.
Based on ethnographic data, this essay analyzes the social order properties of a poor urban street, in a small city in the northeast United States, on which drug dealing is the principle occupation. Rather than treating drug dealing as an agent of disorder, we focus on the order properties of drug dealing and the ordered character of the local code of conduct that develops around it. Like Sudhir Venkatesh (American Journal of Sociology 103:82–111, 1997) we examine the interface between drug dealing and the neighborhood. However, in this small urban space the drug dealers are not outsiders, rather, they are long term residents: established insiders who are well integrated into community life. As such their work practices and the requirements they place on behavior in public spaces impact the neighborhood in comprehensive ways. We detail the phenomenon Elijah Anderson called the “code of the street” (Anderson 1999) as a set of practices and social markers, a local Interaction Order (Goffman, American Sociological Review 48:1–17, 1983; Rawls, Sociological Theory 2:136–149, 1987), that furnishes basic day to day sensemaking tools for residents (Rawls 2009). We propose that this order has a constitutive character that furnishes stable expectations (Garfinkel 1963, 1967) for meaningful social action and identity in the neighborhood. In a context of industrial decline and urban poverty, drug dealing careers constitute a major socialization factor, that touches everyone here—especially children.  相似文献   
868.
This study investigates the factors that shape the attitudes of scientists toward starting their own business or working in a private sector firm. The analysis is based on data collected from scientists working in the German Max Planck Society, a research institution devoted to basic science. We find that the scientists’ attractiveness of working in a private sector firm or of starting their own business differ considerably according to their academic discipline and the self-reported commercial potential of their research. The ability to take risks, prior work experience in private firms, and personal experience in cooperating with industry lead to a positive attitude towards switching to private sector employment or entrepreneurship. Strong willingness to freely distribute research findings is related to a low appeal of private sector work.  相似文献   
869.
870.
Previous research has demonstrated significant sexual dimorphism in friction ridge skin characteristics. This study uses a novel method for measuring sexual dimorphism in finger ridge breadths to evaluate its utility as a sex estimation method from an unknown fingerprint. Beginning and ending in a valley, the width of ten parallel ridges with no obstructions or minutia was measured in a sample of 250 males and females (N = 500). The results demonstrate statistically significant differences in ridge breadth between males and females (p < 0.001), with classification accuracy for each digit varying from 83.2% to 89.3%. Classification accuracy for the pooled finger samples was 83.9% for the right hand and 86.2% for the left hand, which is applicable for cases where the digit number cannot be determined. Weight, stature, and to a lesser degree body mass index also significantly correlate with ridge breadth and account for the degree of overlap between males and females.  相似文献   
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