38 research outputs found
A simple, effective, green method for regioselective 3-acylation of unprotected indoles
A fast and green method is developed for regioselective acylation of indoles in the 3-position without the need for protection of the NH position. The method is based on Friedel-Crafts acylation using acid anhydrides. The method has been optimized, and Y(OTf)3 in catalytic amounts is found to be the best catalyst together with the commercially available ionic liquid [BMI]BF4 (1-butyl-3-methylimidazolium tetrafluoro-borate) as solvent. The reaction is completed in a very short time using monomode microwave irradiation. The catalyst can be reused up to four times without significant loss of activity. A range of substituted indoles are investigated as substrates, and thirteen new compounds have been synthesized
Incidence of Postpartum Infection after Vaginal Delivery in Viet Nam
This study assessed the incidence of postpartum infection which is
rarely clinically evaluated and is probably underestimated in
developing countries. This prospective study identified infection after
vaginal delivery by clinical and laboratory examinations prior to
discharge from hospital and again at six weeks postpartum in Ho Chi
Minh City, Viet Nam. Textbook definitions, physicians' diagnoses,
symptomatic and verbal autopsy definitions were used for classifying
infection. Logistic regression was used for determining associations of
postpartum infection with socioeconomic and reproductive
characteristics. In total, 978 consecutive, eligible consenting women
were followed up at 42\ub17 (range 2-45) days postpartum (not
associated with incidence). Ninety-eight percent took 'prophylactic'
antibiotics. The most conservative estimate of the incidence of
postpartum infection was 1.7%. The incidence of serious infection was
0.5%, but increased to 4.6% when verbal autopsy and symptomatic
definitions were used. Postpartum infection, particularly serious
infection, is greatly underestimated. Just preventing or treating
infection could have a substantial impact on reducing maternal
mortality in developing countries
A free weekly iron-folic acid supplementation and regular deworming program is associated with improved hemoglobin and iron status indicators in Vietnamese women
Background Anemia due to iron deficiency is recognized as one of the major nutritional deficiencies in women and children in developing countries. Daily iron supplementation for pregnant women is recommended in many countries although there are few reports of these programs working efficiently or effectively. Weekly iron-folic acid supplementation (WIFS) and regular deworming treatment is recommended for non-pregnant women living in areas with high rates of anemia. Following a baseline survey to assess the prevalence of anemia, iron deficiency and soil transmitted helminth infections, we implemented a program to make WIFS and regular deworming treatment freely and universally available for all women of reproductive age in two districts of a province in northern Vietnam over a 12 month period. The impact of the program at the population level was assessed in terms of: i) change in mean hemoglobin and iron status indicators, and ii) change in the prevalence of anemia, iron deficiency and hookworm infections. Method Distribution of WIFS and deworming were integrated with routine health services and made available to 52,000 women. Demographic data and blood and stool samples were collected in baseline, and three and 12-month post-implementation surveys using a population-based, stratified multi-stage cluster sampling design. Results The mean Hb increased by 9.6 g/L (95% CI, 5.7, 13.5, p < 0.001) during the study period. Anemia (Hb<120 g/L) was present in 131/349 (37.5%, 95% CI 31.3, 44.8) subjects at baseline, and in 70/363 (19.3%, 95% CI 14.0, 24.6) after twelve months. Iron deficiency reduced from 75/329 (22.8%, 95% CI 16.9, 28.6) to 33/353 (9.3%, 95% CI 5.7, 13.0) by the 12-mnth survey, and hookworm infection from 279/366 (76.2%,, 95% CI 68.6, 83.8) to 66/287 (23.0%, 95% CI 17.5, 28.5) over the same period. Conclusion A free, universal WIFS program with regular deworming was associated with reduced prevalence and severity of anemia, iron deficiency and h
Contribution of Cerebellar Sensorimotor Adaptation to Hippocampal Spatial Memory
Complementing its primary role in motor control, cerebellar learning has also a bottom-up influence on cognitive functions, where high-level representations build up from elementary sensorimotor memories. In this paper we examine the cerebellar contribution to both procedural and declarative components of spatial cognition. To do so, we model a functional interplay between the cerebellum and the hippocampal formation during goal-oriented navigation. We reinterpret and complete existing genetic behavioural observations by means of quantitative accounts that cross-link synaptic plasticity mechanisms, single cell and population coding properties, and behavioural responses. In contrast to earlier hypotheses positing only a purely procedural impact of cerebellar adaptation deficits, our results suggest a cerebellar involvement in high-level aspects of behaviour. In particular, we propose that cerebellar learning mechanisms may influence hippocampal place fields, by contributing to the path integration process. Our simulations predict differences in place-cell discharge properties between normal mice and L7-PKCI mutant mice lacking long-term depression at cerebellar parallel fibre-Purkinje cell synapses. On the behavioural level, these results suggest that, by influencing the accuracy of hippocampal spatial codes, cerebellar deficits may impact the exploration-exploitation balance during spatial navigation
Methyl esterification of carboxylic acids with dimethyl carbonate promoted by K2CO3/tetrabutylammonium chloride
Robustness of Deep Transfer Learning-Based Crack Detection against Uncertainty in Hyperparameter Tuning and Input Data
Computer vision techniques can be applied to detect structural defects of different concrete structures. In this aspect, deep transfer learning algorithms play a key role in terms of automated crack identification. To the best of the authors’ knowledge, selecting appropriate models and tuning them for the classification of crack images, especially in adverse conditions, is a topic that has been neglected until now. Henceforth, to test the robustness and stability of deep transfer learning networks, eight popular pre-trained convolutional neural networks (CNN) models with different network architecture complexities were tasked with image classification challenges. This refinement was created by (i) varying a key hyperparameter used for tuning and (ii) feeding the networks with two variants of adverse conditions in image data. This chapter provides evidence of the optimal batch sizes that should be used and the best repurposed small and large deep learning networks that can achieve outstanding crack classification capabilities with compromised image data. According to the results, GoogleNet and Xception networks have been challenged and confirmed as high-performing networks on average, particularly when used with reasonable batch sizes
Taenia solium cysticercosis in a village in northern Viet Nam: seroprevalence study using an ELISA for detecting circulating antigen
An enzyme-linked immunosorbent assay (ELISA) for detecting circulating Taenia solium antigen was evaluated in Viet Nam; 12 of 210 people gave a positive result, including 5 persons with epilepsy. Cysticercosis was confirmed in 9 persons. Agreement between the ELISA, computerized tomography scanning and biopsy examination was high