An Unusual Metal Templating Effect Switching an N2S2 Ligant to a Binucleating, Tridentate S2O2 Ligand

Natural metalloenzymes not only display extraordinary catalytic activities in biological systems, but also are models for chemists to design organometallic catalysts. Bioinorganic chemical researchers in this field focus on the metal-containing active sites of enzymes. Interestingly, the selections of metal and the responses to the metal substitution of these enzymes are usually surprising due to the unpredictability and variety. A tripeptide Cys-Gly-Cys biomimetic N2S2 ligand class, which is found in acetyl-CoA-synthase active site, has caught attention due to its capability of encapsulating a metal cation giving rise to a variety of MN2S2 units. It has been shown that these units can trap extraneous metal ions using the additional lone pairs of the thiolate sulfurs while keeping the MN2S2 unit intact. Here, when choosing M-ema as the MN2S2 ligand to react with Mn(CO)5Br (ema = N,N’- ethylenebis(2-mercaptoacetamide)), an unprecedented result was obtained, in which M is removed from the tetradentate tight binding site and ema becomes a tridentate binucleating S2O2 ligand to a two-manganese bimetallic system. Characterizations of this novel compound [Mn(CO)3]2(H2ema) were achieved by using infrared spectroscopy, X-Ray diffraction, nuclear magnetic resonance spectroscopy, and mass spectrometry. Different synthetic approaches to [Mn(CO)3]2(H2ema) with modified starting materials reveal a fascinating metal-templated process where folding the backbone of ema ligand is essential to target the final product. This folding process is also reminiscent of tight loops in proteins. The solid-state structure of [Mn(CO)3]2(H2ema) determined via X-ray diffraction shows a pseudo-octahedral geometry around each manganese center which has two bridging thiolate sulfurs, three carbonyls, and one carboxamide oxygen. In addition, two five-membered Mn-S-CH2-C-O rings in which manganese centers reside both hard and soft ligand donor sites suggest prospective applications and exciting reactivities of this complex. Reactivity studies for [Mn(CO)3]2(H2ema) were also conducted. 13CO/12CO exchange experiments in different solvents showed that chemical environments of the three CO ligands are not equivalent. Deprotonation reaction of [Mn(CO)3]2(H2ema) was successful suggesting that the compound may be catalytic active. Moreover, Re and Fe analogues of [Mn(CO)3]2(H2ema) have also been of our interest because of the recent and unique applications of Re and Fe complexes. While many compounds of Re have been extensively used in radiopharmaceuticals, the replacement of Mn centers by Fe would advance our exploration in study of bio-inspired organometallic complexes because Fe ersatz small-molecule mimics have been heavily studied in the last two decades and shown evidence of regioselectivity in ligand substitution. Although [Re(CO)3]2(H2ema) has been successfully prepared and shown similar properties to its analogous Mn compound, the synthesis of [Fe(CO)3]2(H2ema) has faced a challenge because of the instability of the starting material. Lastly, the structures of two related complexes, the Mn4S4 cluster and the [Mn(CO)3]2(half-ema), are also reported

Book excerpt: Making science sustainable

Excerpted from ‘The Vietnamese Social Sciences at a Fork in the Road’, Edited by Quan-Hoang Vuong and Trung Tran [1], with permission from the editors. The Vietnamese Social Sciences and Humanities at a Fork in the Road, utilizing an object-oriented structured database on the productivity of Vietnamese researchers, seeks to provide a comprehensive overview of the development of Social Sciences and Humanities in Vietnam from 2008 to 2018. The book can be ordered from De Gruyter Online or Amazon

Multifractal characterisation of length sequences of coding and noncoding segments in a complete genome

The coding and noncoding length sequences constructed from a complete genome are characterised by multifractal analysis. The dimension spectrum $D_{q}$ and its derivative, the 'analogous' specific heat $C_{q}$, are calculated for the coding and noncoding length sequences of bacteria, where $q$ is the moment order of the partition sum of the sequences. From the shape of the $$ and $C_{q}$ curves, it is seen that there exists a clear difference between the coding/noncoding length sequences of all organisms considered and a completely random sequence. The complexity of noncoding length sequences is higher than that of coding length sequences for bacteria. Almost all $D_{q}$ curves for coding length sequences are flat, so their multifractality is small whereas almost all $D_{q}$ curves for noncoding length sequences are multifractal-like. We propose to characterise the bacteria according to the types of the $C_{q}$ curves of their noncoding length sequences.Comment: 15 pages with 5 figures, Latex, Accepted for publication in Physica

A Retrospective Cohort Study of Kawasaki Disease in Hue Central Hospital for 10 Years (2010-2019)

INTRODUCTION: Kawasaki disease (KD) is an acute self-limited systemic vasculitis of unknown etiology which affects mainly children <5 years of age. If the disease is left untreated, it can lead to serious complications such as inflammation of the blood vessels. AIM: We aim to evaluate the clinical and laboratory findings and response to therapy of KD at Hue Central Hospital. METHODS: This is a retrospective study of patients with KD at Pediatric Center of Hue Central Hospital between January 2010 and December 2019. Clinical and laboratory examinations as well as the echocardiograms finding were analyzed. RESULTS: All patients were under 5 years old, in which boys were more than girls. Fever lasting over 5 days, changing in the mouth mucosa, and peripheral extremities were seen in all patients. About 73.2% had bilateral conjunctivitis and 78.0% had rash. About 42.3% of patients had cervical lymphadenopathy. Laboratory findings were noted with 84.5% of patients had hyperleukocytosis (>12,000/ mm3), 76.2% of patients had high serum C-reactive protein (CRP) levels (>100 mg/dl), 56% of patients had erythrocyte sediment rate >60 mm in the 1st h, and 34.5% of patients had thrombocytosis (platelet count >500,000/mm3) at the time of diagnosis. About 26.2% of patients had coronary artery lesions. Most patients (84.4%) had good outcome since the first dose of gamma-globulin and 13% of patients needed the second dose. There was a significant correlation between coronary artery abnormalities and no or late treatment of gamma-globulin. CONCLUSION: KD was very common in children under 5 years old with the high rate of coronary artery lesion. Treatment with gamma-globulin on or before 10 days of fever resulted in better coronary outcomes and decreased the total length of time of clinical symptoms

Coordination for Connected Automated Vehicles at Merging Roadways in Mixed Traffic Environment

In this paper, we present a two-level optimal control framework to address motion coordination of connected automated vehicles (CAVs) in the presence of human-driven vehicles (HDVs) in merging scenarios. Our framework combines an unconstrained trajectory solution of a low-level energy-optimal control problem with an upper-level optimization problem that yields the minimum travel time for CAVs. We predict the future trajectories of the HDVs using Newell's car-following model. To handle potential deviations of HDVs' actual behavior from the one predicted, we provide a risk-triggered re-planning mechanism for the CAVs based on time-to-conflict. The effectiveness of the proposed control framework is demonstrated via simulations with heterogeneous human driving behaviors and via experiments in a scaled environment.Comment: first manuscript, 7 page

Trends in socioeconomic inequalities in full vaccination coverage among vietnamese children aged 12–23 months, 2000–2014: Evidence for mitigating disparities in vaccination

There has been no report on the situation of socioeconomic inequalities in the full vaccination coverage among Vietnamese children. This study aims to assess the trends and changes in the socioeconomic inequalities in the full vaccination coverage among Vietnamese children aged 12–23 months from 2000 to 2014. Data were drawn from Multiple Indicator Cluster Surveys (2000, 2006, 2011, and 2014). Concentration index (CCI) and concentration curve (CC) were applied to quantify the degree of the socioeconomic inequalities in full immunization coverage. The prevalence of children fully receiving recommended vaccines was significantly improved during 2000–2014, yet, was still not being covered. The total CCI of full vaccination coverage gradually decreased from 2000 to 2014 (CCI: from 0.241 to 0.009). The CC increasingly became close to the equality line through the survey period, indicating the increasingly narrow gap in child full immunization amongst the poor and the rich. Vietnam witnessed a sharp decrease in socioeconomic inequality in the full vaccination coverage for over a decade. The next policies towards children from vulnerable populations (ethnic minority groups, living in rural areas, and having a mother with low education) belonging to lower socioeconomic groups may mitigate socioeconomic inequalities in full vaccination coverage. © 2019 by the authors. Licensee MDPI, Basel, Switzerland. **Please note that there are multiple authors for this article therefore only the name of the first 5 including Federation University Australia affiliate “Huy Nguyen” is provided in this record*

EXTRACURRICULAR SPORTS: POPULAR CONTENTS AND FORMS AMONG STUDENTS IN THE DORMITORY OF VIETNAM NATIONAL UNIVERSITY HO CHI MINH CITY

This article is written to provide thorough information about popular contents and forms of extracurricular sports performed by university students at a dormitory of Vietnam National University Ho Chi Minh City (VNUHCMC). The study uses document references, surveys, and statistical mathematics to investigate what extracurricular sports are favored by the students and how they organize their practices. The results indicate that the majority of students choose to practice football, volleyball, badminton, athletics, and martial arts. They play with themselves and/or in teams, without instructors, from 30 minutes to 02 hours in the afternoon after school time and/or in the morning, at the dormitory and/or sports centers.  Article visualizations

PHYSICAL CONDITION OF MALE STUDENTS AT VIETNAM NATIONAL UNIVERSITY OF HO CHI MINH CITY DORMITORY

The purpose of the study is to provide information about the current physical condition of 19-year-old male students of the Vietnam National University of Ho Chi Minh City (VNUHCMC) dormitory. The research used the methods of synthesizing sport-related documents, interviewing experts, applying pedagogical tests, and statistical analysis to determine appropriate physical fitness assessment tests. Afterward, the figures for the physical condition of male students at the VNUHCMC dormitory were compared with that of the average Vietnamese people, of Hanoi National University (HNU), University of Danang (UD), Can Tho University (CTU), and Ho Chi Minh City (HCMC) students at the same age and gender, and with the standard shown in Decision 53/2008/BGDDT of the Ministry of Education and Training. The results show that the “good” group accounts for 28.75%, the “acceptable” group for 23.19% and the “failed” group for 48.06%. It is notable that the agility, leg muscular strength, endurance, and motor skills of 19-year-old male students at the VNUHCMC dormitory are greater than the average physical fitness of Vietnamese people, as well as students of the same age and gender at HNU, UD, and CTU. Their endurance is also higher than that of male HCMC pupils of the same age, but their leg muscular strength and motor abilities are almost comparable.  Article visualizations