Learning Linear Groups in Neural Networks

Employing equivariance in neural networks leads to greater parameter efficiency and improved generalization performance through the encoding of domain knowledge in the architecture; however, the majority of existing approaches require an a priori specification of the desired symmetries. We present a neural network architecture, Linear Group Networks (LGNs), for learning linear groups acting on the weight space of neural networks. Linear groups are desirable due to their inherent interpretability, as they can be represented as finite matrices. LGNs learn groups without any supervision or knowledge of the hidden symmetries in the data and the groups can be mapped to well known operations in machine learning. We use LGNs to learn groups on multiple datasets while considering different downstream tasks; we demonstrate that the linear group structure depends on both the data distribution and the considered task

Rapport de l'évaluation externe du projet recherche en santé du Centre Régional pour le Développement et la Santé (CREDESA)

Annexes inclusLe Centre Régional pour le Développement et la Santé (CREDESA) - ex Projet de Développement Sanitaire de Pahou (PDSP) a été créé en 1983 au Sud-Est du Bénin avec pour mission : - Promouvoir les soins de santé primaires (SSP) avec une approche pluridisciplinaire et multisectoriel par le biais d'une recherche opérationnelle orientée ·vers les besoins de la communauté; - Assurer avec les communautés des prestations de services rationalisés et la formation des agents de santé communautaire et du personnel de santé à tous les niveaux; Pour répondre à cette mission, le CREDESA a planifié ses activités selon les étapes suivantes : - Etablissement et renforcement de la capacité institutionnelle du CREDESA et de la Faculté des Sciences de la Santé en matière de recherche par le développement des ressources humaines; - Formation des secouristes et des accoucheuses traditionnelles; - Formation d'agents de santé, tels que les médecins, sages-femmes et infirmiers et assistants sociaux. Dans la mise en oeuvre de ce plan dont la troisième phase s'achève en Juin 1996, le CREDESA bénéficie depuis 1990 d'un appui du CRDI. Cet appui a permis la disponibilité de ressources humaines pluridisciplinaires compétentes pour élaborer et mettre en oeuvre des projets de recherche sur les problèmes prioritaires de la zone couverte par le projet, l'organisation des services du district et la formation d'agents de santé et d'agents de santé communautaire. L'exploitation des résultats de recherche et la formation devraient perm.ettre d'asseoir à moyen terme, un système de soins rationalisés et accessibles dans toute la zone de Ouidah. Quelques indicateurs de santé montrent l'impact positif sur la santé des communautés notamment la mortalité infantile qui est très en-dessous de la moyenne nationale. Il s'agit aujourd'hui pour le CREDESA qui vient de franchir un pas de plus dans la reconnaissance internationale en étrennant une troisième distinction internationale (UNICEF), de continuer les activités de service, de formation et de recherche pour d'unè part, suivre ces indicateurs de performance, la qualité de vie des communautés vivant dans ces zones organisées et d'autre part d'organiser le système-recours, en l'occurrence l'hôpital de référence pour son utilisation rationnelle par les populations de la zone. Les populations que nous avons rencontrées y croient fermement et attendent un soutien conséquent de leurs efforts. Mais si le projet connaît de nombreux succès dans ses divers domaines d'intervention, il est important de noter qu'il traîne quelques insuffisances qu'il convient de combler rapidement. En outre, le projet traverse en ce moment une période difficile qui n'est pas sans influence sur la performance et qui a pour origine essentielle : - une restructuration certes nécessaire, mais dont l'application ne va pas sans quelques difficultés heureusement surmontables, - la fin des financements de la part des bailleurs de 'fonds (CRDI, ACDI); ce qui n'est pas sans créer une atmosphère d'inquiétude

Muscular variations in the gluteal region, the posterior compartment of the thigh and the Popliteal fossa: Report of 4 cases

During a study of the sciatic nerve by anatomical dissection in the anatomy laboratory of the Faculty of Medicine and Odontostomatology (FMOS) of Bamako, 4 cases of muscle variations were observed in three male cadavers. The first case was the presence of an accessory femoral biceps muscle that originated on the fascia that covered the short head of the femoral biceps and ended on the head of the fibula joining the common tendon formed by the long and short head of the femoral biceps. The second case was the presence of an aberrant digastric muscle in the gluteal region and in the posterior compartment of the thigh. He had two bellies; the upper belly, considered as a piriform muscle accessory; the lower belly, considered a third head of the biceps femoral muscle; these two bellies were connected by a long tendon. The other two cases were the presence of third head of the gastrocnemius. These two cases were seen bilaterally in a cadaver. The anatomical variations of the hamstring muscles are rare and their knowledge is needed by radiologists and surgeons. The most common cause of popliteal artery entrapment syndrome is the presence of a third head of the gastrocnemius muscle

The association between valence of social media experiences and depressive symptoms

Background: Social media (SM) may confer emotional benefits via connection with others. However, epidemiologic studies suggest that overall SM is paradoxically associated with increased depressive symptoms. To better understand these findings, we examined the association between positive and negative experiences on SM and depressive symptoms. Methods: We conducted a cross-sectional survey of 1,179 full-time students at the University of West Virginia ages 18–30 in August of 2016. Independent variables were self-reported positive and negative experiences on SM. The dependent variable was depressive symptoms as measured using the Patient-Reported Outcomes Measures Information System. We used multivariable logistic regression to assess associations between SM experiences and depressive symptoms controlling for socio-demographic factors including age, sex, race/ethnicity, education, relationship status, and living situation. Results: Of the 1,179 participants, 62% were female, 28% were non-White, and 51% were single. After controlling for covariates, each 10% increase in positive experiences on SM was associated with a 4% decrease in odds of depressive symptoms, but this was not statistically significant (AOR=0.96; 95% CI=0.91-1.002). However, each 10% increase in negative experiences was associated with a 20% increase in odds of depressive symptoms (AOR=1.20; 95% CI=1.11-1.31). When both independent variables were included in the same model, the association between negative experiences and depressive symptoms remained significant (AOR=1.19, 95% CI=1.10-1.30). Conclusion: Negative experiences online may have higher potency than positive ones because of negativity bias. Future research should examine temporality to determine if it is also possible that individuals with depressive symptomatology are inclined toward negative interactions

Selection Criteria for Posterior Circulation Stroke and Functional Outcome Following Mechanical Thrombectomy

Objective: 20% of all acute ischemic strokes (AIS) are caused by posterior circulation strokes, which carry an intensified mortality touching 95%. Early recanalization improves outcome as shown by several reports; however, safety, patient selection, and prognostic factors remain lacking. An investigation of the safety and prognostic factors for posterior circulation mechanical thrombectomy (MT) was performed. Methods: A retrospective review of patients presenting with posterior circulation AIS, who underwent MT between 2010 and 2018. Results: Of 443 patients who underwent MT for AIS, 83 patients had posterior circulation strokes. 95% of procedures were conducted under general anesthesia. The median NIHSS upon admission was 19.1. Half of the patients underwent MT 8 hours from symptom onset, and half required a salvage contact thrombus aspiration after a stent retriever trial with an average of two passes for successful recanalization. The time to achieve revascularization was 61.6 minutes. Mortality rate was 28%, and modified Rankin Scale (mRS) \u3c 2 at three months was seen in 40.1% of surviving patients. A higher functional outcome trend (mRS\u3c2) was seen in patients who underwent MT within 8 hours of symptom onset. The overall complication rate was 28%. Regression analysis showed that stroke subtype, baseline NIHSS, and posterior circulation Alberta Stroke Program Early CT Score (pc-ASPECTS) before thrombectomy were independent predictive factors of positive clinical outcomes. Conclusions: MT is an effective intervention for posterior circulation strokes, and long-term functional independence relies upon proper patient selection. Baseline NIHSS and pc-ASPECTS are independent predictive factors

Effectiveness of a complex, pre-conception intervention to reduce the risk of diabetes by reducing adiposity in young adults in Malaysia:The Jom Mama project - A randomised controlled trial

Background: Pre-conception interventions have the potential to lower non-communicable disease risk in prospective parents and reduce transmission of risk factors such as obesity to the next generation. The Jom Mama project in Malaysia investigated the effectiveness of a combined behaviour change communication and e-health intervention in young married couples prior to first pregnancy. This paper reports the evaluation of the effectiveness of this trial. Methods: Jom Mama was a non-blinded, randomised controlled trial (RCT) conducted in Seremban, Malaysia, over a period of 33 weeks, covering six contact points between trained community health workers and newly married couples before the conception of a first child. Out of 2075 eligible nulliparous women, 549 participated and 305 completed the intervention, with 145 women in the intervention and 160 in the control group. The intervention group received a complex behavioural change intervention, combining behaviour change communication provided by community health promoters and access to a habit formation mobile application, while the control group received the standard care provided by public health clinics in Malaysia. The primary outcome was a change in the woman's waist circumference. Secondary outcomes were anthropometric and metabolic measures, dietary intake (Food Frequency Questionnaire, FFQ), physical activity (International Physical Activity Questionnaire, IPAQ) and mental health (Depression Anxiety Stress Scale, DASS 21). An extensive process evaluation was conducted alongside the trial in order to aid the interpretation of the main findings. Results: There were no significant differences of change in the woman's waist circumference between intervention and control groups at the start and end of the intervention. While the weight, waist circumference and Body Mass Index (BMI) of women in both groups increased, there was a significantly lower increase in the intervention vs the control group over the period of the trial among women who are obese (0.1 kg vs 1.7 kg; P = 0.023, in the intervention and control group respectively). In terms of BMI, the obese intervention subgroup showed a slight reduction (0.01) compared to the obese control subgroup whose BMI increased by 0.7 (P = 0.015). There were no changes in the other secondary outcomes. Conclusions: The Jom Mama pre-conception intervention did not lead to a reduction in waist circumference or significant changes in other secondary outcomes over the eight months prior to conception. However, there was a significantly smaller weight gain in the intervention vs the control group, predominantly in women with pre-existing obesity

FAK acts as a suppressor of RTK-MAP kinase signalling in Drosophila melanogaster epithelia and human cancer cells

Receptor Tyrosine Kinases (RTKs) and Focal Adhesion Kinase (FAK) regulate multiple signalling pathways, including mitogen-activated protein (MAP) kinase pathway. FAK interacts with several RTKs but little is known about how FAK regulates their downstream signalling. Here we investigated how FAK regulates signalling resulting from the overexpression of the RTKs RET and EGFR. FAK suppressed RTKs signalling in Drosophila melanogaster epithelia by impairing MAPK pathway. This regulation was also observed in MDA-MB-231 human breast cancer cells, suggesting it is a conserved phenomenon in humans. Mechanistically, FAK reduced receptor recycling into the plasma membrane, which resulted in lower MAPK activation. Conversely, increasing the membrane pool of the receptor increased MAPK pathway signalling. FAK is widely considered as a therapeutic target in cancer biology; however, it also has tumour suppressor properties in some contexts. Therefore, the FAK-mediated negative regulation of RTK/MAPK signalling described here may have potential implications in the designing of therapy strategies for RTK-driven tumours

The Impact of HIV, an Antiretroviral Programme and Tuberculosis on Mortality in South African Platinum Miners, 1992–2010

HIV and tuberculosis (TB) are the most common causes of death in South Africa. Antiretroviral therapy (ART) programmes should have had an impact on mortality rates. This study describes the impact of HIV, a Wellness (HIV/ART) programme and TB on population-wide trends in mortality and causes of death among South African platinum miners, from before the HIV epidemic into the ART era