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Effectiveness of Wastewater-Based Epidemiology as an Early Warning Tool to Detect SARS-CoV-2 (COVID-19)

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Health 2024年第7期16卷 635-656页

作者： Rakib Ahmed Chowdhury Daniel E. Meeroff Sumaiya Sharmin Alamgir Kabir Sara Hollenbeck Valerie Dalencourt thu nguyen Zack Farmer Frederick Bloetscher Waseem Asghar Stacey Volnick College of Engineering and Computer Science Florida Atlantic University Boca Raton FL USA

Medical diagnostic tests to detect Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) for individuals in the United States were initially limited to people who were traveling or symptomatic to track disease incidence due to the cost of providing testing for all people in a community on a routine basis. As an alternative to randomly sampling large groups of people to track disease incidence at significant cost, wastewater-based epidemiology (WBE) is a well-established and cost-effective technique to passively measure the prevalence of disease in communities without requiring invasive testing. WBE can also be used as a forecasting tool since the virus is shed in individuals prior to developing symptoms that might otherwise prompt testing. this study applied the WBE approach to understand its effectiveness as a possible forecasting tool by monitoring the SARS-CoV-2 levels in raw wastewater sampled from sewer lift stations at a large public university campus setting including dormitories, academic buildings, and athletic facilities. The WBE analysis was conducted by sampling from building-specific lift stations and enumerating target viral copies using RT-qPCR analysis. The WBE results were compared with the 7-day rolling averages of confirmed infected individuals for the following week after the wastewater sample analysis. In most cases, changes in the WBE outcomes were followed by similar trends in the clinical data. The positive predictive value of the applied WBE approach was 86% for the following week of the sample collection. In contrast, positive correlations between the two data with Spearmen correlation (rs) ranged from 0.16 to 0.36. A stronger correlation (rs = 0.18 to 0.51) was observed when WBE results were compared with COVID-19 cases identified on the next day of the sampling events. The P value of 0.007 for Dorm A suggests high significance, while moderate significance was observed for the other dormitories (B, C, and D). The outcomes of this in

关键词： SARS-CoV-2 Wastewater Detection Wastewater-Based Epidemiology (WBE)

Carboxymethyl starch cross-linked by electron beam radiation in presence of acrylic acid sensitizer

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Nuclear Science and Techniques 2013年第B12期24卷 19-22页

作者： Doan Binh nguyen Thanh Duoc Pham thi thu Hong R & D Center for Radiation Technology Vietnam Atomic Energy Institute 202A St. 11 Linh Xuan Ward Thu Duc District Ho Chi Minh City Vietnam

Carboxymethyl starch (CMS) can be cross-linked by electron beam radiation to form a biocompatible and environment-friendly hydrogel at a high absorbed dose and a condensed CMS concentration. Acrylic acid (AAc) can be used as a sensitizer in order to reduce the absorbed doses to an acceptable certain level. At an absorbed dose of 3?4 kGy, the gel content of crosslinked CMS can be obtained about 50% with 5% (w/w) AAc concentration used. The compressive strength of CMS samples increased with increasing their cross-linked densities due to raising absorbed doses. The swelling ratio of cross-linked CMS was also attainable at a maximum of 50 times in the distilled water. The enzymatic degradation of cross-linked CMS was carried out in acetate buffer pH 4.6 with 0.1% α-amylase enzymatic solution incubated at 40oC for 6 h. The crosslinked CMS samples were degraded slower than uncrosslinked CMS ones. The results indicated that the highly cross-linked CMS was almost fully degradable when the enzymatic hydrolysis was performed during 6 h. The FT IR spectra of cross-linked CMS in the presence of AAc were examined to observe the carboxyl group of AAc in the structure of cross-linked CMS. The hydrophilic of cross-linked CMS surface was determined by a contact-angle analysis.

关键词：交联密度羧甲基淀粉电子束辐射丙烯酸敏化剂 FT-IR光谱吸收剂量 CMS

Twin reversed arterial perfusion sequence-a rare and dangerous complication form of monochorionic twins:A case report

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World Journal of Clinical Cases 2022年第28期10卷 10214-10219页

作者： nguyen Duy Anh nguyen-thi thu Ha nguyen-thi Sim nguyen Khac Toan Phan-thi Huyen thuong nguyen Minh Duc Fetal Medicine Center Hanoi Obstetrics and Gynecology HospitalHanoi 100000Vietnam Department of Assisted Reproduction Hanoi Obstetrics and Gynecology HospitalHanoi 100000Vietnam Department of Obstetrics and Gynecology Hanoi University of Medicine and PharmacyHanoi 100000Vietnam Department of Radiology Pham Ngoc Thach University of MedicineHo Chi Minh City 700000Vietnam

BACKGROUND Twin reversed arterial perfusion(TRAP) sequence is an extremely rare congenital anomaly in monochorionic(MC) *** condition is characterized by a malformed fetus(acardiac twin) without cardiac activities being perfused by a structurally normal one(pump twin) via an artery-to-artery anastomosis in a reverse *** SUMMARY We described the first case of TRAP to receive laser surgery in *** 26-wk pregnancy was originally misdiagnosed in another hospital as MC twins with single intrauterine fetal *** admission to our center,the diagnosis was amended to a 26-wk TRAP sequence stage *** acardiac twin was 7.5 cm at the longest length,the ratio of the weight of the acardiac twin to the weight of the pump twin was more than 90%,the pump twin showed fetal distress with absent diastolic flow in umbilical artery of pump twin,and the peak systolic velocity in the middle cerebral artery = 1.6 Mo *** performed emergency laser photocoagulation of the acardiac twin’s umbilical *** surgery,we successfully maintained the pregnancy for 8 wk and ended it electively by cesarean section at 34 wk of gestation due to rupture of *** TRAP should be appropriately diagnosed and treated early to avoid complications of the pump *** laser photocoagulation is a new and effective treatment for this condition.

关键词： Twin reversed arterial perfusion Acardiac twin Pump twin Laser Case report

Electrochemical Immunosensor for Detection of Atrazine Based on Polyaniline/Graphene

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Journal of Materials Science & Technology 2016年第6期32卷 539-544页

作者： nguyen Van Chu nguyen Hai Binh Cao thi Thanh nguyen Van Tu nguyen Le Huy nguyen Tuan Dzung Phan Ngoc Minh Vu thi thu Tran Dai Lam Institute of Materials Science Vietnam Academy of Science and Technology18 Hoang Quoc VietCau Giay.HanoiViet Nam School of Chemical Engineering.Hanoi University of Science and Technology 1 Dai Co VietHanoiViet Ham Institute for Tropical Technology.Vietnam Academy of Science and Technology 18 Hoang Quoc VietHanoiViet Nam Center for High Technology Development Vietnam Academy of Science and Technology18 Hoang Quoc VietHanoiViet Nam University of Science and Technology of Hanoi.18 Hoang Quoc Viet HanoiViet Ham Graduate University of Science and Technology.Vietnam Academy of Science and Technology 18 Hoang Quoc Viet.HanoiViet Nam

In this study, a novel layer-by-layer polyaniline/graphene （PANi/Gr） structure for electrochemical detec- tion of atrazine was developed. Gr film was synthesized by thermal chemical vapor deposition （CVD） method and transferred onto the PANi-predeposited microelectrode. The properties of PANi/Gr film were thoroughly investigated by high-resolution transmission electron microscopy and Raman techniques. The most attractive feature of this system is a suitable microenvironment, which could provide an amplifi- cation of the conductive signal, thus may contribute to enhancing electron transfer and subsequently improve the sensitivity in electrochemical measurements. With low detection limit （- 43 × 10 -12 g/L）, ac-ceptable stability and good reproducibility, the proposed electrochemical immunosensor could be advantageously extended for multiplexed detection of other agents of environmental pollution.

关键词： Electrochemical immunosensor Polyaniline Graphene Atrazine

Infectious etiopathogenesis of Crohn's disease

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World Journal of Gastroenterology 2014年第34期20卷 12102-12117页

作者： Jessica Carriere Arlette Darfeuille-Michaud Hang thi thu nguyen Clermont Universite M2iSHUMR 1071 Inserm University of Auvergne 63001 Clermont-FerrandFrance INRA USC 2018 63000 Clermont-FerrandFrance Centre Hospitalier Universitaire 63000 Clermont-FerrandFrance

Important advances during the last decade have been made in understanding the complex etiopathogenesis of Crohn’s disease(CD).While many gaps in our knowledge still exist,it has been suggested that the etiology of CD is multifactorial including genetic,environmental and infectious *** most widely accepted theory states that CD is caused by an aggressive immune response to infectious agents in genetically predisposed *** rise of genome-wide association studies allowed the identification of loci and genetic variants in several components of host innate and adaptive immune responses to microorganisms in the gut,highlighting an implication of intestinal microbiota in CD ***,numerous independent studies reported a dysbiosis,i.e.,a modification of intestinal microbiota composition,with an imbalance between the abundance of beneficial and harmful *** microorganisms including viruses,yeasts,fungi and bacteria have been postulated as potential CD pathogens,based on epidemiological,clinicopathological,genetic and experimental evidence,their precise role in this disease is not clearly *** review summarizes the current knowledge of the infectious agents associated with an increased risk of developing *** approaches to modulate the intestinal dysbiosis and to target the putative CD-associated pathogens,as well as their potential mechanisms of action are also discussed.

关键词： Crohn's disease Intestinal microbiota Dysbiosis Adherent-invasive Escherichia coli Probiotics Antibiotics Fecal microbiota transplantation

A Raman Study of the Origin of Oxygen Defects in Hexagonal Manganite thin Films

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Chinese Physics Letters 2012年第12期29卷 148-151页

作者： CHEN Xiang-Bai hien nguyen thi Minh YANG In-Sang LEE Daesu NOH Tae-Won Department of Nano Science&Mechanical Engineering and Nanotechnology Research Center Konkuk UniversityChungju 380-701Korea 2Department of Physics and Division of Nano-SciencesEwha Womans UniversitySeoul 120-750Korea 3ReCFIDepartment of Physics and AstronomySeoul National UniversitySeoul 151-747Korea

Oxygen defects are usually unavoidable when synthesizing oxide thin *** study the origin of the oxygen defects in hexagonal manganite HoMnO_(3) epitaxial thin films through Raman scattering *** results show that the oxygen defects in hexagonal HoMnO_(3) thin films have distinct effects on different phonon modes and on magnon *** analyses indicate that the oxygen defects in hexagonal HoMnO_(3) thin films mainly originate from the basal O3 and/or O4 oxygen ***,our analyses of oxygen defects predict that the Mn 3d orbitals would be more strongly hybridized with the apical O1 and/or O22p orbitals than the basal O3 and/or O42p *** prediction is consistent with our resonant Raman scattering study and earlier first-principle calculations of the electronic structures of hexagonal manganites.

关键词： spectroscopy. hexagonal Oxygen

Viral co-infections among children with confirmed measles at hospitals in Hanoi,Vietnam,2014

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Asian Pacific Journal of Tropical Medicine 2017年第2期10卷 164-167页

作者： Hang Le Khanh nguyen Loan Phuong Do Van Thanh thi Trieu Son Vu nguyen Phuong Vu Mai Hoang hien thi Pham Thanh thi Le Huong thi thu Tran Cuong Duc Vuong Mai thi Quynh Le National Institute of Hygiene and Epidemiology No 1-Yesrsin streetHanoiVietnam

Objective:To characterize viral co-infections among representative hospitalized measles cases during the 2014 Hanoi ***:Throat swabs were collected from 54 pediatric patients with confirmed measles,and molecular diagnostics performed for 10 additional viral respiratory pathogens(Influenza A/H1N1pdm09;A/H3N2 and influenza B;Parainfluenza 1,2,3;Respiratory Synctial Virus,RSV;human Metapneumovirus,hM PV;Adenovirus and Picornavirus).Results:Twenty-one cases(38.9%) showed evidence of infection with other respiratory viruses:15 samples contained measles plus one additional virus,and 6 samples contained measles plus 2 additional *** was detected as a predominant cause of co-infections(13 cases;24.1%),followed by RSV(6 cases;11.1%),A/H1N1pdm09(3 cases;5.6%),PIV3(3 cases;3.7%),Rhinovirus(3 cases;3.7%) and hM PV(1 case;1.96%).Conclusions:Viral co-infections identified from pediatric measles cases may have contributed to increased disease severity and high rate of fatal *** treatment of measles cases may require control of multiple viral respiratory pathogens.

关键词： Measles virus Respiratory viruses Co-infection

Measurement of ^(59)Co(ai,x)reaction cross sections with the fast neutrons based on the ^(9)Be(p,n)reaction

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Chinese Physics C 2021年第4期45卷 248-255页

作者： Muhammad Zaman Muhammad Nadeem Muhammad Sahid Kwangsoo Kim Guinyun Kim nguyen thi hien Department of Physics and Center for High Energy Physics Kyungpook National UniversityDaegu 41566Republic of Korea Institute of Physics Vietnam Academy of Science and Technology10 Dao TanHanoiVietnam

The cross sections of the ^(59)Co(n,x)reaction in the average energy range of 15.2-37.2 MeV were meas-ured using activation and an off-line γ-ray spectrometric *** neutrons were generated from the ^(9)Be(p,n)reaction with proton beam energies of 25-45 MeV at the MC-50 Cyclotron facility of the Korean Institute of Radi-ological and Medical Sciences(KIRAMS).Theoretical cal lculations of neutron-induced reactions on ^(59)Co were per-formed using the nuclear model code *** results for the ^(59)Co(n,x)reactions were compared with the theoretical values obtained using TALYS-1.9 and the literature data provided in EXFOR and the TENDL 2019 nuc-lear data *** theoretical values obtained using TALYS-1.9 with adjusted parameters are comparable to the experimental *** measured reaction cross sections of a few radionuclides are new,and the others are compar-able to the literature data,and thus,they can strengthen the *** present study on cross sections leads to useful insight into the mechanisms of ^(59)Co(n,x)reactions.

关键词： ^(59)Co(n,x)reaction cross sections average neutron energy of 15.2-37.2 MeV off-lineγ-ray spectrometry MCNPX 2.6.0 simulation TALYS-1.9

Piaoac Granites Related W-Sn Mineralization, Northern Vietnam: Evidences from Geochemistry, Zircon Geochronology and Hf Isotopes

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Journal of Earth Science 2019年第1期30卷 52-69页

作者： Tuan Anh nguyen Xiaoyong Yang hien Vu thi Lei Liu Insung Lee School of Earth and Space Sciences University of Science and Technology of China Institute of Geological Sciences Vietnam Academy of Science and Technology(VAST) Department of Geology Hanoi University of Mining and Geology School of Earth and Environmental Sciences Seoul National University

Piaoac granites exposed in the Cao Bang region, northern Vietnam, are S-type granite, which are associated with W-Sn-Mo-Be-F mineralization. Zircon U-Pb ages, major and trace elements, mineral chemical and Hf isotopic compositions of the W-Sn-bearing granites from the Piaoac District have been investigated in detail. LA-ICP-MS U-Pb dating of zircon grains from these granites yielded ages of 82.5±2.3 and 82±1.8 Ma, representing an episode of Late Cretaceous magmatic event. These granites are characterized by high peraluminous and have typical S-type geochemical signatures with high SiO_2(72.37 wt.%–73.07 wt.%), high A/CNK values(1.61–1.65) and Al_2O_3(14.4 wt.%–15 wt.%). They are enriched in Rb, U, K, Th, Ta and Pb and display pronounced negative Ba, Sr, Nb, Ti and Eu(Eu/Eu*=0.19–0.24) anomalies. The high degree of fractional crystallization is characterized by low Rb, Sr, Ba and Eu concentrations with high ratios of La/Sm and Eu/Eu*. Zircon grains show εHf(t) values from-9.69 to-0.9 and the corresponding TDM2 range from 1.2 to 1.7 Ga, indicating that these granites could be derived from the Proterozoic basement rocks with minor input from mantle-derived magmas. The calculation of Fe^(3+) and Fe^(2+) of biotites indicates a low oxygen fugacity condition(log fO_2 ranging from 10-17 to 10-18 bars, below MH), which is favorable for the W-Sn mineralization. Tungsten and tin have been enriched in granitic magmas through fractionation, and low oxygen fugacity conditions have promoted the accumulation and transportation of W-Sn in the hydrothermal fluids, leading to deposition of mineral phases. The geochemical data suggest that Piaoac granites formed in an extensional setting related with the Late Cretaceous magmatism occurring large-scale lithospheric extensional in South China Block.

关键词： geochemistry zircon U-Pb age Hf isotope Piaoac granite W-Sn mineralization Northern Vietnam