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Important work has been done to measure legislative effectiveness in the U.S. Congress and to explain the individual characteristics that drive it. Much less attention, however, has been devoted to study the extent to which legislative effectiveness depends on the legislators' social connections. We address this issue with a new model of legislative effectiveness that formalizes the role of social connections, and we test its predictions using the network of cosponsorship links in the 109th–113th Congresses. We propose a new empirical strategy that addresses network endogeneity by implementing a two-step Heckman correction based on an original instrument: the legislators' alumni connections. We find that social connections are a significant determinant of legislative effectiveness. We also study the influence of legislators' characteristics in shaping the network effects. In doing so, we provide new insights into how social connectedness interacts with factors such as seniority, partisanship, and legislative leadership in determining legislators' effectiveness.  相似文献   
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Four fluorescent fingerprint powders (RedWop?, GreenWop?, Basic Yellow?, and Yellow Powder?) were evaluated as a marker for blow fly larvae. Administration methods included ingestion (high vs. low concentration) or topical. Ingestion of high concentrations of Basic Yellow? and RedWop? caused higher larval mortality. Basic Yellow? delayed development and adult emergence while RedWop? and Yellow Powder? had a significant effect on particular stages of development, however, emergence time was not altered. Optimal administration is through ingestion at low concentration levels (<10%) or topically, with GreenWop? demonstrating minimal adverse effects. Optimum wavelength for discrimination between powders was 450 nm. This research can aid in investigative training to increase visibility of larval and pupal blow flies. It can also be used in entomological studies to differentiate between larval blow flies (or other dipteran) species or individuals to further understand complex interactions and behavior during larval development.  相似文献   
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Held at Southampton University's Highfield campus and hosted by iCLIC, an interdisciplinary core on Law, the Internet and Culture, the Data Mining and Data Sharing workshop brought together attendees and speakers from industry, government, academia and a range of disciplines alike. The workshop comprised two sessions, each with a keynote and an associated panel. The first session was chaired by Eleonora Rosati and dealt with copyright and database rights, data mining and data sharing. The second session, chaired by Sophie Stalla-Bourdillon, focussed on data protection, data mining and data sharing. The following report covers both sessions, associated panel discussions and the subsequent question and answer sessions.  相似文献   
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A nontargeted approach based on liquid chromatography equipped with a quadrupole time‐of‐flight mass detector (LC‐MS Q‐TOF) joined to nuclear magnetic resonance (NMR) analysis allowed rapid identification and quantification of the anti‐inflammatory drug aceclofenac in illegal Adderall tablets. The largest chromatographic peak had m/z = 354.030 and m/z = 376.012 matching, respectively, the ionic structures (M + H)+ and (M + Na)+ of a molecule M. The accurate mass data generated the molecular formula C16H13Cl2NO4. A screening of the pharmaceutical active substances having that molecular formula together with the MS/MS fragmentation pattern suggested aceclofenac. Aceclofenac structure was unambiguously confirmed by 1H and 13C NMR experiments. The aceclofenac content was 90 mg/tablet (RSD 2%) as detected by quantitative NMR. Information on the identity and content of illegal drugs is required for legal purposes; it supports in evaluating the effective impact on users safety, and it is useful for control laboratories using a targeted approach in their analytical activities.  相似文献   
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We investigate the determinants of University–Industry (U–I) interactions in the biopharmaceuticals in Italy over the period 2004–2010, choosing co-publishing as a proxy of U–I partnerships. We construct a novel dataset of co-published articles, that contains measures of proximities, agglomeration, firms’ and universities’ characteristics. Following a consolidated methodology, we integrate our dataset of effective interactions with the set of all potential interactions, to estimate probabilistic models for the occurrence and the intensity of U–I interactions. Our main findings confirm and extend the predictions of the previous literature: (1) geographical proximity and prior partnership increase the probability and the intensity of co-publication; (2) the proximity of a firm to other biopharmaceutical firms and universities attenuates the relevance of geographical proximity; (3) there exists complementarity between prior partnerships and geographical proximity. A novel result is that firms’ and Universities’ size, firms’ R&D and patents expenditure and the composition of the academic staff as well as quality of academic research exert a significant impact on the intensity of co-publishing.  相似文献   
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Psychological pain has been reported to be major contributing factor for completed suicide, and classical suicidology based its wisdom on this construct. In this paper we report the case of a patient whose family experienced a high number of suicides apparently due to an escalation of psychological pain in the family members after the successive suicides. We also briefly discuss the problem of helping survivors after the suicide of loved one.  相似文献   
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Several types of biological samples, including hair strands, are found at crime scenes. Apart from the identification of the value and the contributor of the probative evidence, it is important to prove that the time of shedding of hair belonging to a suspect or victim matches the crime window. To this end, to estimate the ex vivo aging of hair, we evaluated time‐dependent changes in melanin‐derived free radicals in blond, brown, and black hairs by using electron paramagnetic resonance spectroscopy (EPR). Hair strands aged under controlled conditions (humidity 40%, temperature 20–22°C, indirect light, with 12/12 hour of light/darkness cycles) showed a time‐dependent decay of melanin‐derived radicals. The half‐life of eumelanin‐derived radicals in hair under our experimental settings was estimated at 22 ± 2 days whereas that of pheomelanin was about 2 days suggesting better stabilization of unpaired electrons by eumelanin. Taken together, this study provides a reference for future forensic studies on determination of degradation of shed hair in a crime scene by following eumelanin radicals by utilizing the non‐invasive, non‐destructive, and highly specific EPR technique.  相似文献   
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The determination of carbon monoxide (CO) and carboxyhemoglobin (COHb) is of utmost importance in forensic toxicology to determine the cause of death in cases of CO poisoning, fire, and explosions. To this end, reliable and updated analytical methods are required. In this paper, four different methods for the determination of carbon monoxide in postmortem blood samples were compared: (i) the spectrophotometric determination of COHb applying the method proposed by Rodkey and modified by Beutler–West, (ii) the spectrophotometric determination of CO using a micro-diffusion-based method, (iii) the determination of CO by gas chromatography coupled to a TCD detector, and (iv) the determination of COHb by blood gas analysis. Three postmortem blood samples were analyzed with all methods, and the results were comparable. The applied methodologies showed different features depending on the sensitivity, sample preparation, and volume. The HS-GC/TCD method in our hand was the most appropriate, on postmortem samples, and versatile to apply. Unfortunately, only a limited number of postmortem blood samples were available for this study due to the rarity of that kind of intoxication in our jurisdiction.  相似文献   
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