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The secondary dentin deposition that occurs after the tooth formation process results in a decrease in pulp cavity volume in adolescents and adults. The purpose of this critical review was to correlate pulpal and/or dental volume on cone-beam computed tomography (CBCT) with chronological age approximation. A subobjective was to investigate which methodology and CBCT technical parameters would be most appropriate to evaluate this correlation. This critical review followed the PRISMA guidelines, and it was conducted by a search through PubMed, Embase, SciELO, Scopus, Web of Science, Cochrane Library databases, as well as gray literature. Primary studies that used pulp volume, or pulp chamber to tooth volume ratio measured using CBCT were included. Seven hundred and eight indexed and 31 non-indexed records were identified. A qualitative analysis was performed including 25 selected studies with a total of 5100 individuals, age ranging from 8 to 87 years without sex predilection. The most used method was pulp volume/tooth volume. CBCT voxel size ranged between 0.09 and 0.5. Manual segmentation associated with threshold algorithms was used in most of the studies. Correlation between the pulp volume/tooth volume ratio was moderate: −0.66 for the upper central incisors, −0.59 for upper canines and −0.56 for lower canines. High heterogeneity was observed among the studies. It is concluded that pulp volume should be used with caution in age estimation. Evidence supports the preferable use of upper incisors with pulp volume/tooth volume ratio for age estimation. There is not enough evidence that voxel size interferes in age estimation by pulp volume.  相似文献   
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Scholars concur that conditional cash transfer (CCT) programs have a strong proincumbent effect among beneficiaries. Although no study has properly focused on the overall effect of cash transfers on incumbents' national vote shares, most scholars have deduced that this effect is positive; i.e., that cash transfers lead to the expansion of incumbents' electoral bases. This article analyzes survey data from nearly all Latin American countries and confirms that beneficiaries of CCT programs are more likely to support incumbents. However, it also shows that CCT programs may induce many voters who were previously incumbent supporters to vote for the opposition. As a consequence, the overall impact of cash transfers on incumbents' vote shares is indeterminate; it depends on the balance between both patterns of behavioral changes among voters. This study is the first to report evidence that cash transfer programs may have significant anti‐incumbent effects.  相似文献   
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This study reports two unusual cases of skull‐encephalic injuries in bathers that were caused by violent impacts with beach umbrellas. The first case concerned a 36‐year‐old man who, while lying on a sun bed, was struck on his left temple by a beach umbrella, which had been blown away by a gust of wind. The second case concerned a six‐year‐old child who was struck on the right temporal region while he was playing on the sand. Both subjects died. A review of the literature was carried out. Various skull and brain injuries caused by several objects were found, but no injuries caused by beach umbrellas were detected. There were only cases of injuries caused by normal umbrellas. These cases showed that several objects can be responsible for traumas causing skull and brain injuries, therefore forensic investigation must be supplemented by circumstantial data.  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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Government effectiveness could be explained by the level of well-informed electorate members, who use the press to learn more about politicians and public servants. Thus, a free press may improve citizens’ accessibility to this information, which in turn will make it more difficult for politicians and public servants to cover up or get away with corrupt behaviour, so the quality of the government could be affected by the media freedom. Accordingly, the main aim of this paper is to determine the effect of the freedom of the press on government effectiveness, considering additionally environmental, institutional, and political characteristics as factors that could determine the level of government effectiveness. To achieve this aim, we examined 202 central governments and compared them across countries using the World Bank data set of Governance Indicators for 2002–2008. The results show that the media, the organizational environment, and political characteristics may be determinants of the level of government effectiveness, taking countries’ economic development into account.  相似文献   
189.
治理河流污染的制度激励悖论分析   总被引:1,自引:0,他引:1  
为了治理日益加剧的河流污染,从中央到地方都相应出台了各种激励措施,但是这些措施并未起到显著效果,却形成了制度激励悖论。排污企业与地方政府在经历了新政策出台初的短暂扰动后,恢复原有均衡。要打破这一均衡,必须改变博弈各方的收益结构、可选策略集以及信息结构等,才有望建立符合科学发展观的最优均衡。  相似文献   
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