Leibniz dans l’Encyclopédie

En étudiant la liste des articles de l’Encyclopédie relatifs à Leibniz, l’on distingue trois contributions majeures : celles des deux éditeurs Diderot et D’Alembert, et celle de Formey. L’oeuvre de Leibniz disponible au XVIIIe siècle restant très partielle, la question des sources et de leur utilisation par les Encyclopédistes se pose d’abord : si Diderot effectue un travail de traduction et de lecture active des concepts philosophiques leibniziens, les Institutions de Physique de la marquise du Châtelet figurent comme source principale de Formey. Enfin, D’Alembert fait référence à l’oeuvre physique et mathématique de Leibniz tout en étendant ses sources à l’ensemble des travaux scientifiques majeurs du XVIIIe siècle. Trois démarches qui nourrissent trois ambitions différentes : pour Diderot, celle de s’approprier les concepts leibniziens selon l’éclectisme philosophique, celle d’une diffusion de la métaphysique wolffienne chez Formey, et enfin pour D’Alembert l’inclusion de Leibniz dans une Histoire des Mathématiques, guidée par son modèle épistémologiqueLeibniz in the EncyclopédieA study of the list of Encyclopédie articles about Leibniz reveals three major contributions, by the two editors, Diderot and D’Alembert, and Formey. Our very partial knowledge of Leibniz’s works available in the 18th Century poses first of all the question of the sources and their use in these articles. While Diderot undertook the translation and active reading of Leibniz’s philosophical concepts, Formey’s main source was the marquise du Châtelet’s Institutions de physique, and D’Alembert referred to Leibniz’s physical and mathematical works while also using all the main 18th-century scientific works. These three different approaches implied three different aims: Diderot wished to appropriate Leibniz’s concepts in the context of his philosophical eclecticism; Formey’s aim was the diffusion of Wolff’s metaphysics; and D’Alembert wanted to include Leibniz in a history of mathematics, guided by his epistemological mode

Orthogonal outlier detection and dimension estimation for improved MDS embedding of biological datasets

Conventional dimensionality reduction methods like Multidimensional Scaling (MDS) are sensitive to the presence of orthogonal outliers, leading to significant defects in the embedding. We introduce a robust MDS method, called DeCOr-MDS (Detection and Correction of Orthogonal outliers using MDS), based on the geometry and statistics of simplices formed by data points, that allows to detect orthogonal outliers and subsequently reduce dimensionality. We validate our methods using synthetic datasets, and further show how it can be applied to a variety of large real biological datasets, including cancer image cell data, human microbiome project data and single cell RNA sequencing data, to address the task of data cleaning and visualization

The key parameters that govern translation efficiency

Translation of mRNA into protein is a fundamental yet complex biological process with multiple factors that can potentially affect its efficiency. Here, we study a stochastic model describing the traffic flow of ribosomes along the mRNA (namely, the inhomogeneous $\ell$-TASEP), and identify the key parameters that govern the overall rate of protein synthesis, sensitivity to initiation rate changes, and efficiency of ribosome usage. By analyzing a continuum limit of the model, we obtain closed-form expressions for stationary currents and ribosomal densities, which agree well with Monte Carlo simulations. Furthermore, we completely characterize the phase transitions in the system, and by applying our theoretical results, we formulate design principles that detail how to tune the key parameters we identified to optimize translation efficiency. Using ribosome profiling data from S. cerevisiae, we shows that its translation system is generally consistent with these principles. Our theoretical results have implications for evolutionary biology, as well as synthetic biology.Comment: To appear in Cell Systems. 32 pages, 10 figures, 1 tabl

PSSA- INTERNATIONAL SOLUTION TO PROTECT THE BIODIVERSITY IN HA LONG BAY - CAT BA MARINE AREA

A Particularly Sensitive Sea Area (PSSA) is an important management tool for biodiversity protection of a marine area. At the time of designation of a Particularly Sensitive Sea Area, an associated protective measure, which meets the requirements of the appropriate legal instrument establishing such measure, must have been approved or adopted by IMO to prevent, reduce, or eliminate the threat or identified vulnerability. Information on each of the Particularly Sensitive Sea Areas (PSSAs) that has been designated by IMO is available on the nautical chart. The Vietnam’s coastal zones and islands are the isolated oceanic habitat of extremely rich marine life in very good condition which is important to the maintenance and dispersal of the marine life of the western tropical Pacific. Vietnam coastal areas are very high risk areas affected by maritime activities, particularly international shipping, therefore in the future identification of some Particularly Sensitive Sea Areas (PSSAs) is necessary. The first Particularly Sensitive Sea Area for Vietnam in Ha Long - Cat Ba was initially proposed in this paper

CHẾ TẠO VÀ TÍNH CHẤT CỦA VẬT LIỆU TỔ HỢP GRAPHENE – ỐNG NANO CÁCBON – HẠT NANO VÀNG

In this work, a composite nanomaterial consisting of graphene (Gr), double-wall carbon nanotube (DWCNTs) and gold nanoparticles (AuNPs), designated as DWCNTs-AuNPs-Gr was synthesized via the thermal chemical vapour deposition technique. The morphology and electrical and electrochemical properties of the material were characteried by using field emission scanning electron microscopy, Raman spectroscopy, four-probe sheet resistance measurement, and cyclic voltammetry (CV). The average sheet resistance value of DWCNTs-AuNPs-Gr is 549 W/sq, 2.3 times lower than that of graphene. The current response of a DWCNTs-AuNPs-Gr-modified electrode in a 2 mM K3[Fe(CN)6]/K4[Fe(CN)6] solution with 0.1 M PBS is 15.79 µA, 1.48 times higher than that of a graphene-modified electrode and 2.57 times higher than that of a bare electrode. The DWCNTs-AuNPs-Gr material can be used for electrochemical biosensors to detect various bioelements.Trong công trình này, màng tổ hợp của vật liệu graphene (Gr) – ống nano cácbon hai tường (DWCNT) và hạt nano kim loại vàng (AuNPs) (DWCNT-AuNPs-Gr) đã được chế tạo bằng phương pháp lắng đọng pha hơi nhiệt hóa học (CVD). Hình thái học bề mặt và các tính chất điện, điện hóa của vật liệu tổ hợp đã được khảo sát thông qua kính hiển vi điện tử quét phát xạ trường, phổ Raman, điện trở bốn mũi dò và kỹ thuật quét thế vòng (CV). Với nồng độ DWCNTs 0,3 g/L và tốc độ quay phủ 4000 vòng/phút, vật liệu DWCNTs-AuNPs-Gr có điện trở bề mặt giảm 2,3 lần so với màng Gr và đạt khoảng 549 W/sq; dòng đỉnh đáp ứng trong dung dịch 2 mM K3[Fe(CN)6]/K4[Fe(CN)6] trong 0,1 M PBS đạt 15,79 µA tại 50 mV/s, cao gấp 1,48 lần so với điện cực biến tính màng Gr và gấp 2,57 lần so với điện cực trần. Vật liệu DWCNTs-AuNPs-Gr có tiềm năng ứng dụng trong cảm biến điện hóa để phát hiện các phần tử sinh học khác nhau

Evaluation of Ursolic Acid as the Main Component Isolated from Catharanthus Roseus against Hyperglycemia

ABSTRACT. Ursolic acid with large amount (0.67% of dried plant weight) along with 7 compounds, namely as spatozoate (1), kaurenoic acid (2), ursonic acid (3), 3-hydroxy-11-ursen-28,13-olide (4), ursolic acid (5), vindoline (6) and mixture of β-sitosterol and stigmasterol were isolated from dichloromethane and ethyl acetate extracts which have shown anti-glucosidase activity of the whole plant of C.roseus. Some isolated compounds and their derivatives were also tested for anti-glucosidase and cytotoxicity.Ursolic acid was examined for hypoglycemic activity in alloxan-induced diabetic mice with dose of 200 and 300 mg/kg/day, respectively. The results have shown that the blood glucose level were reduced by 45.75% and 51.31% to compare with the control group. This study has confirmed that the main component of Vietnamese C. roseus has had significant anti-hyperglycemia activity

COVID-19 outbreak after 100 days without community transmission: Epidemiological analysis of factors associated with death

Background: Outbreak of SARS-CoV-2 pandemic has caused millions of deaths and lifelong consequences since December 2019. We attempted to evaluate the incidence, distribution, and risk factors associated with death after applying the social distance strategy to the second wave of SARS-CoV-2 in the Danang outbreak in Vietnam.Methods: We retrospectively reviewed the online the Danang Hospital reports, gathering the epidemiological history of confirmed SARS-CoV-2 patients. We then conducted a descriptive analysis of Fisher’s Phi Coefficient and Cramer’s, along with multiple logistic regression models to test the effects of symptomatology and control measures performed by Vietnamese government. The last report we examined on August 29, 2020.Results: A total of 389 SARS-CoV-2 confirmed cases were related to the Danang outbreak are included in our analysis with a mean age of 47.1 (SD = 18.4), involving 154 men and 235 women, with 34 cases of death and 355 were alive. The study showed significant results related to age, quarantine measures, previous negative SARS-CoV-2 test, and a range of symptoms, including shortness of breath and myalgia (p-value <0.05). Our multiple-variable analysis suggested the significant risk of death was related to age, severe symptomology, undetected SARS-CoV-2 test results, and prior quarantined SARS-CoV-2 history.Conclusions: Vietnamese authorities had implemented successful quarantine practices to control the SARS-CoV-2 outbreaks. However, this virus has shown dynamic spread beyond the ability of the country to control its transmission. Adequate screening, social distancing, and adequate care of elderly and healthcare workers can lower the risk of future outbreaks

Acceptance and user experiences of a wearable device for the management of hospitalized patients in COVID-19–designated wards in Ho Chi Minh City, Vietnam: action learning project

Background: Wearable devices have been used extensively both inside and outside of the hospital setting. During the COVID-19 pandemic, in some contexts, there was an increased need to remotely monitor pulse and saturated oxygen for patients due to the lack of staff and bedside monitors. Objective: A prototype of a remote monitoring system using wearable pulse oximeter devices was implemented at the Hospital for Tropical Diseases in Ho Chi Minh City, Vietnam, from August to December 2021. The aim of this work was to support the ongoing implementation of the remote monitoring system. Methods: We used an action learning approach with rapid pragmatic methods, including informal discussions and observations as well as a feedback survey form designed based on the technology acceptance model to assess the use and acceptability of the system. Based on these results, we facilitated a meeting using user-centered design principles to explore user needs and ideas about its development in more detail. Results: In total, 21 users filled in the feedback form. The mean technology acceptance model scores ranged from 3.5 (for perceived ease of use) to 4.4 (for attitude) with behavioral intention (3.8) and perceived usefulness (4.2) scoring in between. Those working as nurses scored higher on perceived usefulness, attitude, and behavioral intention than did physicians. Based on informal discussions, we realized there was a mismatch between how we (ie, the research team) and the ward teams perceived the use and wider purpose of the technology. Conclusions: Designing and implementing the devices to be more nurse-centric from their introduction could have helped to increase their efficiency and use during the complex pandemic period

Measuring the Prevalence of Mental Disorders in Adolescents in Kenya, Indonesia, and Vietnam: Study Protocol for the National Adolescent Mental Health Surveys

Purpose: In low- and middle-income countries, there are limited data on mental disorders among adolescents. To address this gap, the National Adolescent Mental Health Surveys (NAMHS) will provide nationally representative prevalence data of mental disorders among adolescents in Kenya, Indonesia, and Vietnam. This paper details the NAMHS study protocol. Methods: In each country, a multistage stratified cluster sampling design will be used. Participants will be eligible pairs of adolescents aged 10–17 years and their primary caregiver. Adolescents will be assessed for social phobia, generalized anxiety disorder, major depressive disorder, attention-deficit/hyperactivity disorder, conduct disorder, and post-traumatic stress disorder using the Diagnostic Interview Schedule for Children, version 5. Demographics, risk and protective factors, and service use information will also be collected. In the parallel clinical calibration study, diagnoses of major depressive disorder, social phobia, and generalized anxiety disorder made using the Diagnostic Interview Schedule for Children, version 5 will be calibrated against a diagnostic assessment by in-country clinicians in a separate sample. Results: Data collection for the national survey and clinical calibration study will commence in 2021, with dissemination of findings and methodology due to occur in 2022. Conclusions: Accurately quantifying the prevalence of mental disorders in adolescents is essential for service planning. NAMHS will address this lack of prevalence data, both within the NAMHS countries and within their respective regions, while establishing a gold-standard methodology for data collection on adolescent mental health in low- and middle-income countries. More broadly, NAMHS will encourage capacity building within each country by establishing linkages between researcher, clinician, government, and other networks