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Olefin Polymerization Behavior of Titanium(IV) Complexes with Fluorinated and Non-fluorinated aliphatic Phenoxyimine Ligands

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Chinese Journal of Polymer science 2024年第1期42卷 52-62,I0007页

作者： Vladislav A.Tuskaev Kasim F.Magomedov svetlana Ch.Gagieva Dmitry A.Kurmaev Yulia V.Nelyubina Evgenii K.Golubev Maria D.Evseeva Viktor G.Vasil'ev Galina G.Nikiforova Mikhail I.Buzin Vyacheslav s.Bogdanov Boris M.Bulychev Department of Chemistry M.V.Lomonosov Moscow State UniversityMoscow 119992Russian Federation A.N.Nesmeyanov Institute of Organoelement Compounds Russian Academy of SciencesMoscow119991Russian Federation Enikolopov Institute of synthetic Polymer Materials Russian Academy of SciencesMoscow 117393Russian Federation

A series of Ti(Ⅳ) dichloride and dialkoxide com plexes with phenoxyimine ligands containing fluorinated and nonfluorinated aliphatic imine fragments have been *** molecular structures of complexes 1 and 4 were established by single-crystal X-ray diffraction *** complexes adopt a distorted octahedral coordination structure around the titanium atom and two oxygen atoms are situated in trans position while two nitrogen atoms and two outgoing ligands(Cl or iPrO) are situated in cis *** of activators(MMAO-12 and combinations Et_nAICl_(3-n)+Bu_(2)Mg) and outgoing ligand(Cl or iPrO) nature on the catalytic activity and properties of the resulting polymers was *** Ti complexes,despite the nature of the outgoing ligands(Cl or iPrO) in the presence of al/Mg activators,was found to display a high ethylene polymerization activity in the range 1600-3830 kg_(polymer)·mol_(Ti)^(-1)·h^(-1)·atm^(-1) with a viscosity average molecular weight(M_v) value in the range 1.1×10~6-7.1×10~6 Dalton(Da).The resulting UHMWPE can be processed by a solventless method into high-strength and high-modulus oriented *** rheological characteristics of a polymer melt have been *** absence of a cross-over point did not allow to compare the values of the molecular weight distribution of polymers obtained on fluorinated and non-fluorinated pre-catalysts,however,the estimation of the entanglement density is in good agreement with the mechanical characteristics of oriented film *** activation with methylalumoxane,the activity of the com plexes decreased very significantly;however,a polymer with a molecular weight of about 12 million Da was *** the process of ethylene/octene-1 copolymerization,fluorine-containing precatalysts showed a clear advantage over non-fluorinated analogues both in activity and in comonomer content.

关键词： FI catalysts Titanium(IV) (Co)polymerization al/Mg co-catalyst Ultra-high molecular weight polyethylene

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Evaluation of the Quality and safety of Hand sanitizers Marketed in saudi Arabia

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Health 2022年第5期14卷 523-534页

作者： Ibrahim A. al Othaim Turki F. al-Mutari Nasser s. Bakiri Khalid M. Bin shehail Fouza K. al-Enazi Fahad s. aldawsari Anwar s. al suhaibani Yahya M. alshehri Reference Laboratory for Medicine and Cosmetics Saudi Food and Drug Authority (SFDA) Riyadh Saudi Arabia National Drug and Cosmetic Control Laboratories Saudi Food and Drug Authority (SFDA) Riyadh Saudi Arabia

Background: Hand sanitizers are an important preventive measure to halt the spread of pathogens, which has become a huge demand during the coronavirus disease (COVID-19). Consequently, their safety and quality are top priorities for regulatory organizations. Methods: saudi Food & Drug Authority laboratories have analyzed numerous samples of hand sanitizers in order to ensure their safety and efficacy. Active ingredients, as well as hazardous impurities, have been checked according to the pharmacopeia. Results: In this study, we report the results of the analysis of 1409 samples, which represent the majority of products available in the saudi Arabian market. The results showed that 196 samples (13.9%) did not meet international standards. specifically, out of 196 failed samples, 75, 12, and 4 products contained hazardous substances such as methanol, 1-propanol, and acetaldehyde, respectively. Additionally, some failed samples contained foreign particles, were improperly labeled, or contained an inadequate concentration of alcohol. Conclusion: The substandard hand sanitizers possess a risk to the community, particularly during pandemics, and hence stringent yet dynamic regulations should be implemented.

关键词： Hand sanitizer COVID-19 Us FDA Ethanol Methanol

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Racial and Ethnic Differences in Orthorexia Nervosa symptomatology and Other Disordered Eating

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Open Journal of Psychiatry 2024年第4期14卷 287-299页

作者： Dilan H. Arreguin Kendria s. shields-Rhodes Melissa L. Harel Crystal D. Oberle Department of Psychology Texas State University San Marcos TX USA

While some research has explored racial and ethnic differences in disordered eating, this study may be the first to examine these differences in orthorexia nervosa, involving obsessive-compulsive thoughts and behaviors concerning healthy eating, which negatively impact one’s life. Adult participants, recruited from college courses and social media, completed an online survey with the Orthorexia Nervosa Inventory (ONI) and the Eating Attitudes Test-26 (EAT-26). Regarding racial and ethnic background, 743 were White, 249 were Hispanic, 87 were Black, 61 were Asian or Pacific Islander, and 110 were biracial/multiracial. A MANCOVA revealed that the racial and ethnic groups.did not differ on the ONI subscales assessing orthorexic behaviors, impairments, and emotions, after accounting for gender, BMI, and EAT-26 total scores that were covariates. In contrast, a second MANCOVA did reveal group differences on the EAT-26 subscales, after accounting for gender, BMI, and ONI total scores that were covariates. Black participants scored significantly lower than the other racial and ethnic groups on the subscale assessing dieting behaviors characteristic of anorexia nervosa, and the subscale assessing binge-eating and purging behaviors characteristic of bulimia nervosa. Further, Hispanic participants scored significantly lower than White participants on the latter subscale. These findings suggest that while orthorexic symptomatology does not differ based on race and ethnicity, a Black race and Hispanic ethnicity may be protective factors against disordered eating, perhaps related either to cultural norms concerning body image or to the resiliency and social support among the Black and Hispanic communities.

关键词： Race Ethnicity Orthorexia Disordered Eating

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Optimizing the Double Inverted Pendulum′s Performance via the Uniform Neuro Multiobjective Genetic algorithm

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International Journal of Automation and computing 2017年第6期14卷 686-695页

作者： Dony Hidayat al-Janan Hao-Chin Chang Yeh-Peng Chen Tung-Kuan Liu Institute of Engineering science and Technology National Kaohsiung First University of Science and TechnologyTaiwanChina Mechanical Engineering Departement Engineeering FacultySemarang State UniversitySemarangCenter of JavaIndonesia Institute of Engineering science and Technology National Kaohsiung First University of Science and TechnologyTaiwanChina

An inverted pendulum is a sensitive system of highly coupled parameters, in laboratories, it is popular for modelling nonlinear systems such as mechanisms and control systems, and also for optimizing programmes before those programmes are applied in real situations. This study aims to find the optimum input setting for a double inverted pendulum（DIP）, which requires an appropriate input to be able to stand and to achieve robust stability even when the system model is unknown. such a DIP input could be widely applied in engineering fields for optimizing unknown systems with a limited budget. Previous studies have used various mathematical approaches to optimize settings for DIP, then have designed control algorithms or physical mathematical *** study did not adopt a mathematical approach for the DIP controller because our DIP has five input parameters within its nondeterministic system model. This paper proposes a novel algorithm, named Uni Neuro, that integrates neural networks（NNs） and a uniform design（UD） in a model formed by input and response to the experimental data（metamodel）. We employed a hybrid UD multiobjective genetic algorithm（HUDMOGA） for obtaining the optimized setting input parameters. The UD was also embedded in the HUDMOGA for enriching the solution set, whereas each chromosome used for crossover, mutation, and generation of the UD was determined through a selection procedure and derived individually. subsequently, we combined the Euclidean distance and Pareto front to improve the performance of the algorithm. Finally, DIP equipment was used to confirm the settings. The proposed algorithm can produce 9 alternative configured input parameter values to swing-up then standing in robust stability of the DIP from only 25 training data items and 20 optimized simulation results. In comparison to the full factorial design, this design can save considerable experiment time because the metamodel can be formed by only 25 experiments using the UD. Furth

关键词： Double inverted pendulum(DIP) Uni Neuro-hybrid UD multiobjective genetic algorithm(HUDMOGA) uniform design(UD) metamodel euclidean distance

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The Effect of Physical Factors on Fecal Coliform Viability Rate in sewage sludge

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Journal of Geoscience and Environment Protection 2014年第2期2卷 9-13页

作者： s. N. al-Bahry I. Y. Mahmoud s. K. al-Musharafi 1Department of Biology College of Science Sultan Qaboos University Muscat Oman 2Department of Biological Sciences and Chemistry University of Nizwa Nizwa Oman 3Department of Applied Biotechnology Sur College of Applied Sciences Sur Oman

Experiments were conducted on the survival rate of fecal coliform after spreading the sewage sludge for desiccation on sludge beds in an open field throughout the year. The ambient temperature, humidity, sunlight intensity and solar radiation were measured during the period of sludge desiccation. The maximum average temperature, sunlight intensity and solar radiation were recorded throughout the year. During May and August the minimum microbial counts were recorded after four weeks of sludge desiccation. Relative humidity did not have significant effect on survival rate. The minimum microbial counts were taken after four weeks of sludge drying. When the sludge was mixed with three different media, the maximum count of fecal coliform was presented when soil mixed with sludge and irrigated with treated sewage effluent (TsE). When soil mixed with sludge irrigated with well water, the number of fecal coliform count dropped significantly. The minimum count occurred when compost was used instead of sludge. This was a clear indication that the source of contamination was from sludge and was mostly contributed by the TsE irrigation. The use of dried sludge after four weeks of treatment had the lowest fecal coliform count and was safe to be used as fertilizer for farming. Oman is located in a semi-equatorial belt with arid environmental conditions which are ideal for elimination of microbial pathogens. Thus, sludge desiccation in such environmental conditions, specifically during the hot months of the year, is perfect for such practice.

关键词： sewage sludge Treated sewage Effluent Fecal Coliform Viability Rate Environmental Factors

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Polyethylene glycol has immunoprotective effects on sciatic allografts, but behavioral recovery and graft tolerance require neurorrhaphy and axonal fusion

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Neural Regeneration Research 2025年第4期20卷 1192-1206页

作者： Tyler A.smith Liwen Zhou Cameron L.Ghergherehchi Michelle Mikesh Cathy Z.Yang Haley O.Tucker JuliAnne allgood Jared s.Bushman George D.Bittner Department of Molecular Biosciences University of Texas at AustinAustinTXUSA Department of Neuroscience University of Texas at AustinAustinTXUSA Division of Pharmaceutical sciences University of WyomingLaramieWYUSA

Behavioral recovery using(viable)peripheral nerve allografts to repair ablation-type(segmental-loss)peripheral nerve injuries is delayed or poor due to slow and inaccurate axonal ***,such peripheral nerve allografts undergo immunological rejection by the host immune *** contrast,peripheral nerve injuries repaired by polyethylene glycol fusion of peripheral nerve allografts exhibit excellent behavioral recovery within weeks,reduced immune responses,and many axons do not undergo Wallerian *** relative contribution of neurorrhaphy and polyethylene glycol-fusion of axons versus the effects of polyethylene glycol per se was unknown prior to this *** hypothesized that polyethylene glycol might have some immune-protective effects,but polyethylene glycol-fusion was necessary to prevent Wallerian degeneration and functional/behavioral *** examined how polyethylene glycol solutions per se affect functional and behavioral recovery and peripheral nerve allograft morphological and immunological responses in the absence of polyethylene glycol-induced axonal ***-type sciatic nerve injuries in outbred sprague–Dawley rats were repaired according to a modified protocol using the same solutions as polyethylene glycol-fused peripheral nerve allografts,but peripheral nerve allografts were loose-sutured(loose-sutured polyethylene glycol)with an intentional gap of 1–2 mm to prevent fusion by polyethylene glycol of peripheral nerve allograft axons with host *** to negative control peripheral nerve allografts not treated by polyethylene glycol and in contrast to polyethylene glycol-fused peripheral nerve allografts,animals with loose-sutured polyethylene glycol peripheral nerve allografts exhibited Wallerian degeneration for all axons and myelin degeneration by 7 days postoperatively and did not recover sciatic-mediated behavioral functions by 42 days *** morphological signs of rejection,such as col

关键词： allograft rejection axotomy macrophage myelin nerve repair polyethylene glycol(PEG) sciatic nerve T cell transplantation Wallerian degeneration

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selenium Nanoparticles Ameliorative Effect on Acetaminophen Hepatotoxicity in Male Mice

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Natural science 2017年第7期9卷 207-215页

作者： Mohammad s. al-Harbi sayed A. M. Amer Department of Biology Faculty of Science Taif University Taif Saudi Arabia College of Forensic sciences Naif Arab University for Security Sciences Riyadh Saudi Arabia Zoology Department Faculty of Science Cairo University Giza Egypt

selenium nanoparticles (seNPs) have been widely used as anti-inflammatory and anti-toxic agent. The present study used Bacillus tequilensis for biosynthesizing seNPs from sodium selenite (Na2seO3) and investigated its ameliorative effects on acetaminophen (APAP) hepatotoxicity in male mice. The results indicated that alanine transaminase (alT), aspartate aminotransferase (AsT) and alkaline phosphatase (alP) significantly elevated in mice treated with APAP, while other liver markers (total proteins and albumin) did not change. seNPs either alone or in combination with APAP showed ameliorative effects on liver enzymes to some extents where their activities decreased to be insignificant with those of normal group. A slight variation was shown in total antioxidant capacity (TAC). Histopathologically, the hepatocytes of the mice treated with APAP showed cloudy swelling and vacuolar degeneration, while those treated with seNPs or both seNPs and APAP appeared more or less histologically normal. In conclusion, seNPs can be used to improve or replace today’s therapies of APAP hepatotoxicity.

关键词： seNPs Mice APAP Hepatotoxicity Antioxidant

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Tissue-specific isoenzyme variations in Arabian camel, <i>Camelus dromedaries</i>

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Advances in Bioscience and Biotechnology 2012年第7期3卷 863-868页

作者： Mohammed s. al-Harbi sayed A. M. Amer Department of Biology Faculty of Science Taif University Taif Saudi Arabia

Malate dehydrogenase, α-esterase and β-esterase isoenzymes have been analyzed by native polyacryla-mide gel electrophoresis in different tissues (liver, kidney, muscle and hump) of the Arabian Camel, Camelus dromedaries in order to study the tissue specificity of these isoenzymes. Malate dehy-drogenase recorded three fractions while both este-rases recorded two fractions in different studied tissues. Malate dehydrogenase was considered as a key isoenzyme in discriminating among the different studied tissues. The percentage amount of both Mdh-1 and Mdh-2 showed significant difference among the different tissues while Mdh-3 recorded significant variation between muscle and hump tissues. The significant variation in the amount of Mdh isoenzyme (on the level of either total or fractions) among the different studied tissues may reflect the role of this enzyme for energy production in this desert animal. With respect to esterases, the percentage amount for both fractions and the total enzyme did not show significant difference among different tissues except β-Est-2 which was significantly higher in hump than in muscle. This enzyme showed higher thickness and intensity in both liver and kidney than in the muscle and hump indicating its greater activity in both liver and kidney.

关键词： Electrophoresis Esterase Malate Dehydrogenase Tissue specificity Arabian Camel

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Near-surface soil Chemical Properties as Affected by Cover Crops Over Time in the Lower Mississippi River Valley

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Agricultural sciences 2024年第9期15卷 1035-1056页

作者： Cooper Fanning Kristofor R. Brye Michael B. Daniels Trenton L. Roberts samuel Fernandes Lisa s. Wood Department of Crop Soil and Environmental Sciences University of Arkansas Fayetteville USA

Typical row-crop agricultural practices can potentially be harmful to soil health and future sustainability. The use of cover crops (CC) as a mechanism to improve soil health on a wide scale remains underutilized. soil health remains a major concern for the sustainability of agricultural productivity, therefore, research into CC implementation as a mean to preserve or improve soil health is warranted. The objective of this study was to evaluate the effects of CC on the soils in the eastern Arkansas portion of the Lower Mississippi River Valley (LMRV) over time for various chemical soil parameters, including pH, soil organic matter (sOM), soil elemental contents (i.e., P, K, Ca, Mg, s, Na, Fe, Mn, Zn, Cu, and B), soil respiration, and a generalized soil health score index. soil pH decreased over time under both CC and no-cover-crop (NCC) treatments, by −0.3 and −0.2, respectively. soil OM decreased over time under NCC by −0.1%, but did not differ between CC treatments. soil N availability decreased over time under NCC (−22.6 kg·ha−1), but did not change over time under CC. soil respiration decreased over time under both CC and NCC, by −76.1 mg·L−1 and −77.3 mg·L−1, respectively, though there was no effect of CC treatment. The Haney soil health score index decreased under CC (−7.0) and NCC (−6.8) without an effect from CC treatment. Results of the study place emphasis on the temporal nature of soil health as influenced by cover crops and their potential to improve soil health.

关键词： Arkansas Cover Crops soil Properties soil Organic Matter soil Health score

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Bithalamic Ischemic stroke in sickle Cell Patient at the Kamenge University Hospital in Burundi: Case Report

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Open Journal of Medical Imaging 2024年第2期14卷 72-78页

作者： sébastien Manirakiza Daniel Nduwayo Patrice Barasukana Chantal Murekatete Jean Bosco Bizimana alice Ndayishimiye Léopold Nzisabira Hélène Bukuru Department of Radiology Kamenge University Hospital Center University of Burundi Bujumbura Burundi Department of Internal Medicine Neurology Kamenge University Hospital Center University of Burundi Bujumbura Burundi Department of surgery Neurosurgery Kamenge University Hospital Center University of Burundi Bujumbura Burundi Department of Pediatrics Kamenge University Hospital Center University of Burundi Bujumbura Burundi

Aim: To describe the clinical and radiological diagnostic for a sickle cell patient who got a bithalamic vasculature accident. Observation: This was a 4-year-old female child admitted to the pediatric ward for convulsive seizures in a feverish context. The physical examination did not find signs of meningeal irritation. The effective workup including thick gout, lumbar puncture, complete blood count, and C reactive protein was normal. An electrocencephalogram was not performed due to lack of availability of the device. Based on clinical data and the fact that Burundi is an area of high malaria prevalence, antimalarial and anticonvulsant treatment has been started. An alteration of consciousness (the Glasgow score of 7) had motivated a CT scan. Bithalamic hypodensities in favor of a vascular accident have been demonstrated. Etiological investigation revealed homozygous sickle cell disease ss during hemoglobin electrophoresis. The final evolution has been characterized by a return to normal consciousness. Conclusion: The complexity of the clinical picture following occlusion of Percherons artery makes it difficult to diagnose. sickle cell disease may favour the occurrence of ischaemic lesions. Cerebral imaging enables the diagnosis to be made with certainty and avoids delays in treatment.

关键词： stroke Bithalamic Infarction sickel Cell Percheron Artery

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