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Mechanistic Study of Ruthenium(III) Catalyzed Oxidation of Cyclohexanone by Acidic Bromate

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Journal of Surface Engineered Materials and Advanced Technology 2018年第2期8卷 27-36页

作者： Yasir Arafat lone Masood Ayoub Kaloo Faizan Danish Khaleel Department of Chemistry Lovely Professional University Phagwara India Department of Chemistry Government Degree College Shopian India Department of Chemistry Islamic University of Science and Technology Awantipora India

In this work, kinetics and mechanism of Ru(III) catalyzed oxidation of cyclohexanone by acidified solution of potassium bromate has been studied. Present study employ mercuric acetate Hg (OAc)2 as a scavenger for Br¯?ion to prevent parallel oxidation by bromine. The kinetics and mechanism have also been studied in the temperature range of 30°C - 45°C. The reaction exhibits first order kinetics with respect to Ru (III), while zero order kinetics with respect to KBrO3 and HClO4. The influence of Hg(OAc)2 and ionic strength on the rate of reaction was found to be insignificant. Positive effect in the reaction mixture was also observed upon addition of chloride ion;while as the negative effect was revealed with acetic acid. A suitable mechanism in conformity with the kinetic observations has been proposed and the rate law is derived on the basis of obtained data. The various activation parameters such as energy of activation (ΔE*), Arrhenius factor (A), entropy of activation (ΔS*) were calculated from the rate measurements at 30°C, 35°C - 40°C and 45°C.

关键词： Kinetics Ru (III) Oxidation Ketone Bromate Acidic Order

Mapping of the Water Table Levels of Unconfined Aquifers Using Two Interpolation Methods

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Journal of Geographic Information System 2016年第4期8卷 480-494页

作者： Oswaldo Augusto Filho Wanessa Soares Clemente Iriguay fernandéz Geotechnical Department Engineering School of Sao Carlos University of Sao Paulo Sao Paulo Brazil Department of Civil Engineering University of Granada Granada Spain

The spatial prediction of the water table can be used for many applications related to civil works (foundations, excavations) and other urban and environmental management activities. Deterministic and geostatistical interpolation methods were used to predict the spatial distribution of water table levels (unconfined aquifers) of important geological formations of the Joao Pessoa City (capital of Paraiba State, Brazil) with dense urban occupation and high demand for new civil works. The deterministic (topo to raster) and geostatistical (ordinary kriging) interpolation methods were evaluated using a Geographic Information System (GIS)-based investigation. The water table levels were obtained from 276 boring logs of Standard Penetration Test (SPT) in situ investigation distributed over the geological formations studied (an area of 59.8 km2, covering 40 districts of the Joao Pessoa City). The Nspt values and textural characterization data are stored for levels of 1 m depth. Some boreholes located in the area investigated were not included in the interpolation processes in order to be compared with estimated values (validation of the results). Maps of the water table depths were also produced to further analyze the quality of the water table surfaces interpolated by both methods. The phreatic surface interpolations provided satisfactory results for both methods (RMSE = 1.8 m). The topo to raster method showed a slight general tendency to be less affected by local values in relation to the kriging method and also has the advantage of integrating the drainage flow system, which is a relevant aspect for spatial models of the water table levels of unconfined aquifers. The ordinary kriging (geostatistical method) provides a prediction surface and some measure of the certainty or accuracy of the predictions.

关键词： Water Table Deterministic and Geostatistical Interpolation Methods SPT Boreholes Geological-Geotechnical Database

Crystal Structures of Human 17<i>β</i>-Hydroxysteroid Dehydrogenase Type 1 Complexed with the Dual-Site Inhibitor EM-139

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Health 2018年第8期10卷 1079-1089页

作者： Tang Li Daowei Zhu fernand Labrie Shengxiang Lin CHU de Quebec Research Center and Department of Molecular Medicine Laval University Quebec City Canada EndoCeutics Inc. Quebec City Canada

Human 17β-hydroxysteroid dehydrogenase type 1 (17β-HSD1) catalyzes the biosynthesis of the most potent natural estrogen 17β-estradiol (E2) from estrone (E1) in the ovary and peripheral tissues, playing a pivotal role in the progression of estrogen-dependent diseases. N-n-Butyl-N-methyl-ll-(16'α-chloro-3',17'β-dihydroxyestra-1',3',5'(10')-trien-7'α-yl)undecanamide (EM-139) was previously described as a dual-site inhibitor that can inhibit 17β-HSD1 transforming E1 into E2 and also inhibit estrogen receptor. In the present report, we describe the co-crystallization of EM-139 with 17β-HSD1 as well as the analysis of the three-dimensional structure of the enzyme/inhibitor complex. The crystal is grown under similar condition as native crystals, whereas the space group is changed to I121 never observed in other 17β-HSD1 crystals before. The steroidal moiety of the bound EM-139 molecule has shown a binding pattern similar to E2 in the E2 binary complex. The O-3 of the inhibitor develops hydrogen bonds with residues His221 and Glu282, whereas the O-17 makes hydrogen bonds with Ser142 and Tyr155. The bulky 7α-alkyl moiety of the inhibitor, which is essential for its anti-estrogenic activity but cannot be defined in the electron density, may compromise the inhibitory effect of EM-139 to 17β-HSD1. Moreover, the 16α-Cl atom shows no obvious interaction with surrounding residues. The atomic level understanding of the inhibitory mechanism of EM-139 provides important information for the inhibitor design of 17β-HSD1, which will facilitate future development of more potent and selective inhibitors of the enzyme for therapeutic purposes.

关键词： 17β-HSD1 Inhibitor Complex Structure Estrogen-Dependent Diseases

Molecular epidemiology, characterization of virulence factors and antibiotic resistance profile of Streptococcus agalactiae isolated from dairy farms in China and Pakistan

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Journal of Integrative Agriculture 2023年第5期22卷 1514-1528页

作者： Ambreen LEGHARI Shakeel Ahmed LAKHO Faiz Muhammad KHAND Khaliq ur Rehman BHUTTO Sameen Qayoom lone Muhammad Tahir ALEEM Iqra BANO Muhammad Ali CHANDIO Jan Muhammad SHAH LIN Hui-xing FAN Hong-jie MOE Joint International Research Laboratory of Animal Health and Food Safety College of Veterinary MedicineNanjing Agricultural UniversityNanjing 210095P.R.China Shaheed Benazir Bhutto University of Veterinary and Animal Sciences Sakrand 67210Pakistan Central Veterinary Diagnostic Laboratory Tando Jam 70050Pakistan Jiangsu Co-innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses Yangzhou UniversityYangzhou 225009P.R.China

Streptococcus agalactiae is one of the most common pathogens that cause bovine mastitis worldwide. Identifying pathogen prevalence and virulence factors is critical for developing prevention and control approaches. Herein, 1 161 milk samples from various dairy farms in China(n=558) and Pakistan(n=603) were collected between 2019–2021 and were subjected to S. agalactiae isolation. Prevalence, serotyping, virulence genes, and antibiotic-resistant genes of S. agalactiae were evaluated by PCR assay. All isolates were characterized for haemolysis, biofilm production, cytotoxicity, adhesion, and invasion on bovine mammary epithelial cells. The prevalence of S. agalactiae-induced mastitis in cattle was found to be considerably higher in Pakistan than in China. Jiangsu and Sindh provinces had the highest area-wise prevalence in China and Pakistan, respectively. Serotypes Ia and II were prevalent in both countries, whereas serotype III was found only in Pakistan. Moreover, all isolates tested positive for PI-2b gene but negative for PI-1 and PI-2a genes. All isolates harboured cfb, cylE, hylB, and fbsB virulent genes, whereas many of them lacked bibA, rib and bca. However, the absence of bac and scp genes in Chinese isolates and cspA in Pakistani isolates was noted, while spb1 and lmb were not detected in isolates of both countries. Pakistani isolates, particularly serotype Iapositive, had a considerably higher ability to produce biofilm, haemolysis, cytotoxicity, adhesion, and invasion than Chinese isolates. Most of the isolates were phenotypically resistant to tetracycline, erythromycin, and clindamycin and genotypic resistance was confirmed by the presence of ermA, ermB, tetM and tetO genes. Our study highlights the antimicrobial resistance profile and virulence-related factors contributing to the epidemiological spread of mastitis-causing S. agalactiae in China and Pakistan. The findings may facilitate future studies designed to develop improved treatment and control str

关键词： Streptococcus agalactiae mastitis epidemiology virulence characterization antibiotic resistance

Petroleum geoscience in Norden - exploration, production and organization

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Episodes 2008年第1期31卷 115-124页

作者： Anthony M. Spencer Per Ivar Briskeby lone Dyrmose Christensen Rune Foyn Marie KjФlleberg Erling Kvadsheim Ian Knight Morten Rye-Larsen John Williams StatoilHydro Forushagen 4035 Stavanger Norway. StatoilHydro 0240 Oslo Norway. StatoilHydro 9481 Harstad Norway. ConocoPhillips P.O. Box 220 4098 Tananger Norway. Norwegian Petroleum Directorate P.O. Box 600 4003 Stavanger Norway. StatoilHydro PO Box 7200 5020 Bergen Norway.

Offshore exploration in Norway and Denmark-in the North Sea, the Norwegian Sea and the Barents Sea-has involved drilling about 850 wildcat wells, resulting in about 300 oil and gas finds, of which 84 are fields with production. The recoverable resources of all these finds total about 65 billion barrels of oil equivalent. Almost all these hydrocarbons come from a Jurassic source and the main reservoirs and traps are Jurassic sandstones in fault blocks and Paleocene sandstones or Cretaceous chalks in gentle domes. The article describes four major fields-Ekofisk, Gullfaks, Ormen Lange and SnФhvitto illustrate some of the many challenges in developing and producing the hydrocarbons. Elsewhere in Norden, there has been much less exploration. Drilling results have mostly been negative in mainland Sweden, onshore Denmark, onshore Svalbard and on- and offshore West Greenland. Minor oil finds have been made in Palaeozoic rocks in the Baltic Sea. The first wells have recently been drilled off the Faroe Islands, resulting in one discovery. No drilling has taken place on- or offshore East Greenland. As a result of the hydrocarbon activities in Norway and Denmark, petroleum geoscience there has flourished, with 2000 geoscientists currently employed in the industry, many technical innovations made, a wealth of publically available information and a great increase in the understanding of the geology.

关键词：石油勘探地球科学资源开发地质特征

Role of preputial washing in reducing microbial load and improving bovine semen quality

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Asian pacific Journal of Reproduction 2018年第3期7卷 97-102页

作者： Adil Rasool Paray Mukesh Bhakat Shabir Ahmad lone Tushar Kumar Mohanty Ranjana Sinha Javid Ur Rahman Zahid Bashir Khanday Ziaullah Danish Artificial Breeding Research Centre ICAR-National Dairy Research InstituteKarnal132001HaryanaIndia

Quality semen production remains the main focus and objective of semen processing laboratories throughout the world. Bacterial and other microbial contaminants affect the semen quality and hence the fertility, and also lead to reproductive disorders as well as lower conception rates and increased embryonic mortality, abortion and other complications in females. Microbial contamination affects the semen adversely, by exerting direct spermicidal effect, formation of reactive oxygen species, toxin production, adherence with spermatozoa, deriving nutrients and oxygen from the medium and thus competing with spermatozoa for the factors of growth and normal functioning. Despite hygienic measures, several ubiquitous and opportunistic microbes find their ways into semen during collection, processing, and storage of semen, and survive even during freezing. Stringent sanitary precautions are therefore required at every step of collecting semen and its processing. Preputial cavity is considered as main source of semen contaminating microorganisms. Flushing the preputial cavity with normal saline or any suitable liquid combination with antimicrobial activity, prior to semen collection reduces the microbial load and thereby improves the semen quality.

关键词： Semen quality Preputial washing Microbial contamination

Calcium-Magnesium Ca/Mg Ratios and Their Agronomic Implications for the Optimization of Phosphate Fertilization in Rainfed Rice Farming on Acidic Ferralsol in the Forest Zone of Ivory Coast

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Design and Multicriteria Optimization of a Two-Stage Reactive Extrusion Process for the Synthesis of Thermoplastic Polyurethanes

Open Journal of Soil Science（土壤科学期刊） 2024年第1期

作者： fernand G.Yao Brahima Kone Franck M.L.Bahan Kouadio Amani Jean L.Essehi Mamadou B.Ouattara Konan E.B.Dibi Brou Kouame François Lompo Albert Yao-Kouame

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Engineering（科研） 2012年第9期4卷 497-514页

作者： Sandrine Hoppe Dimitrios Meimaroglou Mauricio Camargo Christian Fonteix fernand Pla Equipe de Recherche des Processus Innovatifs (ENSGSI) Université de Lorraine Nancy France Laboratoire Réactions et Génie des Procédés (CNRS) Université de Lorraine Nancy France Université de Lorraine Nancy France

This paper presents the implementation of two multicriteria optimization methods based on different approaches, namely, Rough Set Method (RSM) and Net Flow Method (NFM), to the manufacture by reactive extrusion of linear thermoplastic polyurethanes (TPUs), appropriate for medical applications. A preliminary study allowed determining the process operating conditions for which the polymerization time and the average residence time of the reactants in the extruder are of the same order of magnitude. Prior to the optimization, a neural network model able to predict with acceptable accuracy the effect of the operating conditions on the output process variables, was constructed and validated. This model was then used to determine, using Pareto’s concept, a set of non-dominated solutions constituting Pareto’s domain. These solutions were then ranked according to the preferences of a decision maker using NFM and RSM. This allowed providing the 10% highest ranked solutions of Pareto’s domain and proposing a set of optimal operating conditions for the production, with the lowest energy consumption, of TPUs with targeted properties and high purity. Experimental validation runs carried out under similar operating conditions gave rise to criteria values confirming the su- perior performance of NFM, without rejecting, at the same time, the values obtained using RSM.

关键词： Reactive Extrusion Thermoplastic Polyurethanes Modelling Multicriteria Optimization Decision-Making Support

Change in Preoperative Nervousness: A Randomized Controlled Trial in Gynecological Cancer Patients

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Health 2016年第3期8卷 219-229页

作者： Marianne K. Thygesen René De Pont Christensen lone Hedemand Ole Mogensen Institute of Clinical Research Faculty of Health Sciences University of Southern Denmark Odense Denmark Department of Obstetrics and Gynaecology Odense University Hospital Odense Denmark Research Unit of General Practice University of Southern Denmark Odense Denmark

Patients are often nervous prior to surgery and females might suffer the most. Increased nervousness needs attention as it can negatively affect postoperative recovery. Support from nurses, i.e. being present, attentive, empowering and helpful to the patient, and talking about what is on the patient’s mind, might help to reduce nervousness. However, there is a lack of evidence as to the ideal level of attention and resources to reduce preoperative nervousness. The objective of the current study was to compare a range of care combinations with standard care to female patients prior to sedation and cancer surgery primarily on difference in change in nervousness from admission until sedation before cancer surgery, measured on a Visual Analouge Scale. Using simple randomization and numbers in sealed envelopes, adult gynaecological patients scheduled for open cancer surgery were allocated to care provided by a nurse anaesthetist and: A) a surgical nurse, B) no additional care, C) a known nurse , and D) a relative. Only the statistician was blinded. The trial stopped when the calculated numbers were included. In the full analysis set, compared to standard care A) (n = 61), we observed the following mean changes and [95% confidence intervals]: B) (n = 65) 1.05 [CI: 0.298 to 1.794] with p = 0.006, C) (n = 61): -0.38 [-1.140 to 0.385] with p = 0.330, D) (n = 71): 0.23 [-0.498 to 0.967] with p = 0.528. Female cancer patients will benefit from supportive care by a surgical nurse from the time of arrival on the operating ward plus supportive care from a nurse anesthetist from 5 - 10 minutes after entering the operating ward. It is not recommended at any time to rely fully on the support of relatives. The effect on adults of preoperative painful procedures and patients’ time alone on the operating ward should be further investigated.

关键词： Anxiety Cancer Perioperative Care Randomized Controlled Trial Women’s Health