Differences in Physical Fitness and Body Composition Between Active and Sedentary Adolescents: A Systematic Review and Meta-Analysis

Journal of Youth and Adolescence - Previous research analyzing the differences in physical fitness and body composition between active and sedentary adolescents aged 12–16 has not provided...     

Autonomy and distance from the centre as drivers of innovation in the public sector: Testing a positioning-based hypothesis

A generally accepted assumption is that innovation in the public sector is easier when managers have more autonomy. Previous research has revealed a paradox: the most innovative organizations are autonomous organizations, but also central agencies, more so than ministries. What has not been documented so far in Canada is the quality and nature or type of innovation by location. We developed a database of applications for IPAC's innovative management award with 1712 innovations in federal and provincial governments over the past 29 years. Using statistical analysis that takes into account the proximity of applicant organizations to political power, we provide a picture of innovation and institutional position in the public sector in Canada.     

Automated detection of regions of interest in cartridge case images using deep learning

This paper explores a deep-learning approach to evaluate the position of circular delimiters in cartridge case images. These delimiters define two regions of interest (ROI), corresponding to the breech face and the firing pin impressions, and are placed manually or by an image-processing algorithm. This positioning bears a significant impact on the performance of the image-matching algorithms for firearm identification, and an automated evaluation method would be beneficial to any computerized system. Our contribution consists in optimizing and training U-Net segmentation models from digital images of cartridge cases, intending to locate ROIs automatically. For the experiments, we used high-resolution 2D images from 1195 samples of cartridge cases fired by different 9MM firearms. Our results show that the segmentation models, trained on augmented data sets, exhibit a performance of 95.6% IoU (Intersection over Union) and 99.3% DC (Dice Coefficient) with a loss of 0.014 for the breech face images; and a performance of 95.9% IoU and 99.5% DC with a loss of 0.011 for the firing pin images. We observed that the natural shapes of predicted circles reduce the performance of segmentation models compared with perfect circles on ground truth masks suggesting that our method provide a more accurate segmentation of the real ROI shape. In practice, we believe that these results could be useful for firearms identification. In future work, the predictions may be used to evaluate the quality of delimiters on specimens in a database, or they could determine the region of interest on a cartridge case image.     

The accumulation and transmission of wealth over a long period: example of a rural family from Loire-Atlantique in the 19th and early 20th centuries

This research seeks to trace the transfer of wealth down the male line of a rural French family through the 19th and 20th centuries, and to decipher the logic of accumulating and transferring wealth. The subject will be approached from an angle different from that of Segalen [Ethnol. Fr. 8 (1978) 271], who followed which farmers had cultivated the same farm through two centuries. The itinerary of wealth passing through the six generations examined here was traced using the range of legal documents that mark a person's life: purchases, sales, exchanges, marriage contracts, gifts, and inheritances. Wealth behavioral patterns that are assumed to follow an economic logic are described using neoclassical economic models.     

Labour market segmentation in Cameroonian manufacturing

The economic crisis in Cameroon has provided a test for distinct causes of labour market segmentation. Many firms that previously followed rigid legislation have ceased to do so, while a traditional informal sector has continued outside almost all regulation. We categorise workers as informal, formal, or regulated, by firm characteristics, and test for labour market segmentation between these sectors. Direct legislation is the most significant cause of segmentation. We find limited evidence that the costs of becoming formal create rationing in formal‐sector jobs. While addressing both sets of rigidities would have maximum impact on unemployment in Cameroon, reforming direct labour legislation is likely to have the most beneficial short‐term impact.     

Sovereignty and Representation

In this contribution the author explores some aspects of the relation between sovereignty, democracy and representation. After shortly focusing on the idea of sovereignty, he then questions Rousseau's refusal to take representation into account within a democratic framework, an idea that is however latent in his general approach.     

Review: The physiology of saliva and transfer of drugs into saliva

Although saliva or oral fluid “lacks the drama of blood, the sincerity of sweat and the emotional appeal of tears”, quoting Mandel in 1990 [I.D. Mandel, The diagnostic uses of saliva, J. Oral Pathol. Med. 19 (1990) 119–125], it is now meeting the demand for inexpensive, non-invasive and easy-to-use diagnostic aids for oral and systemic diseases, drug monitoring and detection of illicit use of drugs of abuse, including alcohol. As the salivary secretion is a reflex response controlled by both parasympathetic and sympathetic secretomotor nerves, it can be influenced by several stimuli. Moreover, patients taking medication which influences either the central nervous system or the peripheral nervous system, or medication which mimic the latter as a side effect, will have an altered salivary composition and salivary volume. Patients suffering from certain systemic diseases may present the same salivary alterations. The circadian rhythm determines both the volume of saliva that will and can be secreted and the salivary electrolyte concentrations. Dietary influences and the patient's age also have an impact on composition and volume of saliva. The latter implies a wide variation in composition both inter- and intra-individually. Sampling must therefore be performed under standardized conditions. The greatest advantage, when compared to blood sample collection, is that saliva is readily accessible and collectible. Consequently, it can be used in clinically difficult situations, such as in children, handicapped and anxious patients, where blood sampling could be a difficult act to perform.