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Influence of Co-Catalyst Concentration on the Formation of Active Centers and the Polymerization Rate in Catalytic Ziegler Natta Ethene Slurry Polymerization
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作者 Heinrich Trischler Martin Ruff Christian Paulik 《材料科学与工程(中英文A版)》 2012年第7期511-518,共8页
关键词 催化剂浓度 助催化剂 聚合速率 活性中心 淤浆聚合 ZIEGLER-NATTA 纳塔 乙烯
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Forests with high structural complexity contribute more to land surface cooling:empirical support for management for complexity
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作者 Prakash Basnet Simon Grieger +1 位作者 Birgitta Putzenlechner Dominik Seidel 《Journal of Forestry Research》 2025年第4期111-126,共16页
Forests play a vital role in mitigating climate change through their physiological functions and metabolic processes,including their ability to convert solar energy into biomolecules.However,further research is necess... Forests play a vital role in mitigating climate change through their physiological functions and metabolic processes,including their ability to convert solar energy into biomolecules.However,further research is necessary to elucidate how structural characteristics of a forest and topographic settings influence energy conversion and surface temperature of a forest.In this study,we investigated a beech forest in central Germany using airborne laser scanning(ALS)point cloud data and land surface temperature(LST)data derived from Landsat 9 satellite imagery.We constructed 30 m×30 m plots across the study area(approximately 17 km2)to align the spatial resolution of the satellite imagery with the ALS data.We analyzed topographic variables(surface elevation,aspect and slope),forest attributes(canopy cover,canopy height,and woody area index),as well as forest structural complexity,quantified by the box-dimension(Db).Our analysis revealed that LST is significantly influenced by both forest attributes and topographic variables.A multiple linear regression model demonstrated an inverse relationship(R^(2)=0.38,AIC=8105)between LST and a combination of Db,elevation,slope,and aspect.However,the model residuals exhibited significant spatial dependency,as indicated by Moran’s I test.To address this,we applied a spatial autoregressive model,which effectively accounted for spatial autocorrelation and improved the model fit(AIC=746).Our findings indicate that elevation exerts the most substantial influence on LST,followed by forest structural complexity,slope,and aspect.We conclude that forest management practices that enhance structural complexity can effectively reduce land surface temperatures in forested landscapes. 展开更多
关键词 Airborne laser scanning TOPOGRAPHY Box-dimension Landsat satellite imagery Land surface temperature
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A Review of Modern Strategies for Enhancing Power Quality and Hosting Capacity in Renewable-Integrated Grids:From Conventional Devices to AI-Based Solutions
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作者 Adel A.Abou El-Ela Ragab A.El-Sehiemy +2 位作者 Abdallah Nazih Asmaa A.Mubarak Eman S.Ali 《Computer Modeling in Engineering & Sciences》 2025年第11期1349-1388,共40页
Distribution systems face significant challenges in maintaining power quality issues and maximizing renewable energy hosting capacity due to the increased level of photovoltaic(PV)systems integration associated with v... Distribution systems face significant challenges in maintaining power quality issues and maximizing renewable energy hosting capacity due to the increased level of photovoltaic(PV)systems integration associated with varying loading and climate conditions.This paper provides a comprehensive overview on the exit strategies to enhance distribution system operation,with a focus on harmonic mitigation,voltage regulation,power factor correction,and optimization techniques.The impact of passive and active filters,custom power devices such as dynamic voltage restorers(DVRs)and static synchronous compensators(STATCOMs),and grid modernization technologies on power quality is examined.Additionally,this paper specifically explores machine learning and AI-driven solutions for power quality enhancement,discussing their potential to optimize system performance and facilitate renewable energy integration.Modern optimization algorithms are also discussed as effective procedures to find the settings for power system components for optimal operation,including the allocation of distributed energy resources and the tuning of control parameters.Added to that,this paper explores the methods to maximize renewable energy hosting capacity while ensuring reliable and efficient system operation.By synthesizing existing research,this review aims to provide insights into the challenges and opportunities in distribution system operation and optimization,highlighting future research directions that enhance power quality and facilitate renewable energy integration. 展开更多
关键词 Distribution system enhancement power quality renewable energy sources harmonic mitigation hosting capacity maximization filter placement optimization stochastic modeling
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Complexity of vitamin E metabolism 被引量:4
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作者 Lisa Schmolz Marc Birringer +1 位作者 Stefan Lorkowski Maria Wallert 《World Journal of Biological Chemistry》 CAS 2016年第1期14-43,共30页
Bioavailability of vitamin E is influenced by several factors, most are highlighted in this review. While gender, age and genetic constitution influence vitamin E bioavailability but cannot be modified, life-style and... Bioavailability of vitamin E is influenced by several factors, most are highlighted in this review. While gender, age and genetic constitution influence vitamin E bioavailability but cannot be modified, life-style and intake of vitamin E can be. Numerous factors must be taken into account however, i.e., when vitamin E is orally administrated, the food matrix may contain competing nutrients. The complex metabolic processes comprise intestinal absorption, vascular transport, hepatic sorting by intracellular binding proteins, such as the significant α-tocopherol-transfer protein, and hepatic metabolism. The coordinated changes involved in the hepatic metabolism of vitamin E provide an effective physiological pathway to protect tissues against the excessive accumulation of, in particular, non-α-tocopherol forms. Metabolism of vitamin E begins with one cycle of CYP4F2/CYP3A4-dependent ω-hydroxylation followed by five cycles of subsequent β-oxidation, and forms the water-soluble end-product carboxyethylhydroxychroman. All known hepatic metabolites can be conjugated and are excreted, depending on the length of their sidechain, either via urine or feces. The physiological handling of vitamin E underlies kinetics which vary between the different vitamin E forms. Here, saturation of the side-chain and also substitution of the chromanol ring system are important. Most of the metabolic reactions and processes that are involved with vitamin E are also shared by other fat soluble vitamins. Influencing interactions with other nutrients such as vitamin K or pharmaceuticals are also covered by this review. All these processes modulate the formation of vitamin E metabolites and their concentrations in tissues and body fluids. Differences in metabolism might be responsible for the discrepancies that have been observed in studies performed in vivo and in vitro using vitamin E as a supplement or nutrient. To evaluate individual vitamin E status, the analytical procedures used for detecting and quantifying vitamin E and its metabolites are crucial. The latest methods in analytics are presented. 展开更多
关键词 Vitamin E metabolism Long-chain metabolites of vitamin E Vitamin E bioavailability Vitamin E transport
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Novel method for determination of sodium in foods by thermometric endpoint titrimetry (TET) 被引量:3
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作者 Thomas Smith Christian Haider 《Journal of Agricultural Chemistry and Environment》 2014年第1期20-25,共6页
A novel yet simple, rapid and robust thermometric endpoint titration (TET) method for the determination of sodium in various foodstuffs is described. Sodium reacts exothermically with aluminium in the presence of an e... A novel yet simple, rapid and robust thermometric endpoint titration (TET) method for the determination of sodium in various foodstuffs is described. Sodium reacts exothermically with aluminium in the presence of an excess of potassium and fluoride ions to form NaK2AlF6 (“elpasolite”). This reaction forms the basis of a ro- bust, reliable analytical procedure suitable for routine process control. The reaction of calcium under similar conditions (to form KCaAlF6) suggests that potentially, calcium may interfere in the determination of sodium in some foodstuffs. Results of an investigation suggest that at molar ratios [Ca]/[Na] < 0.85, an error of <1% of the measured value of sodium is incurred. 展开更多
关键词 SODIUM TITRATION Food Foodstuffs TET Thermometric ENDPOINT TITRATION ELPASOLITE
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采用UV光诱导微孔发泡产生3D结构的胶印新方法 被引量:2
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作者 Sandra Schlgl Martin Reischl +2 位作者 Volker Ribitsch Wolfgang Kern 何文 《中国印刷与包装研究》 CAS 2012年第2期73-77,共5页
0引言近年来,科研人员研发出多种新型印刷技术和印刷油墨,以实现不同基底上制备凸起三维(3D)结构。本研究开发出一种基于光化学反应的新型发泡油墨,无须其他辅助工艺。
关键词 结构 光化学反应 胶印 3D 诱导 UV 印刷油墨 印刷技术
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Pseudo-or real progression? An ovarian cancer patient under nivolumab:A case report 被引量:1
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作者 Mona Passler Eliane T Taube +1 位作者 Jalid Sehouli Klaus Pietzner 《World Journal of Clinical Oncology》 CAS 2019年第7期247-255,共9页
BACKGROUND Checkpoint-Inhibition has revolutionized the treatment for several entities such as melanoma and renal cell carcinoma.The first encouraging experience in ovarian cancer was reported for nivolumab,a fully hu... BACKGROUND Checkpoint-Inhibition has revolutionized the treatment for several entities such as melanoma and renal cell carcinoma.The first encouraging experience in ovarian cancer was reported for nivolumab,a fully humanized anti-programmed death-1 antibody.Pseudoprogression is a new phenomenon associated with these novel immuno-oncologic agents.It can be explained by infiltrating leucocytes and edema that result in a temporary increase in tumor size and delayed subsequent shrinkage due to tumor cell destruction.CASE SUMMARY We report on a 47-year old patient with platinum-resistant ovarian cancer that was treated off-label with nivolumab 3mg/kg iv d1q14d.She first experienced classic pseudoprogression with inguinal lymph node swelling after cycle two and subsequent shrinkage.After 6 cycles she presented with rectal bleeding and progressive disease was diagnosed due to new tumor infiltration into the rectum.CONCLUSION Clinicians should be aware of pseudoprogression,its underlying mechanisms and strategies to discriminate pseudo-from real progression in ovarian cancer. 展开更多
关键词 Case report Nivolumab Clinical ONCOLOGY CHECKPOINT inhibition GYNECOLOGIC ONCOLOGY PSEUDOPROGRESSION Immunooncology
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A multi-stage triaxial testing procedure for low permeable geomaterials applied to Opalinus Clay 被引量:1
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作者 Katrin M. Wild Marco Barla +1 位作者 Giovanni Turinetti Florian Amann 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2017年第3期137-148,共12页
In many engineering applications,it is important to determine both effective rock properties and the rock behavior which are representative for the problem’s in situ conditions.For this purpose,rock samples are usual... In many engineering applications,it is important to determine both effective rock properties and the rock behavior which are representative for the problem’s in situ conditions.For this purpose,rock samples are usually extracted from the ground and brought to the laboratory to perform laboratory experiments such as consolidated undrained(CU)triaxial tests.For low permeable geomaterials such as clay shales,core extraction,handling,storage,and specimen preparation can lead to a reduction in the degree of saturation and the effective stress state in the specimen prior to testing remains uncertain.Related changes in structure and the effect of capillary pressure can alter the properties of the specimen and affect the reliability of the test results.A careful testing procedure including back-saturation,consolidation and adequate shearing of the specimen,however,can overcome these issues.Although substantial effort has been devoted during the past decades to the establishment of a testing procedure for low permeable geomaterials,no consistent protocol can be found.With a special focus on CU tests on Opalinus Clay,this study gives a review of the theoretical concepts necessary for planning and validating the results during the individual testing stages(saturation,consolidation,and shearing).The discussed tests protocol is further applied to a series of specimens of Opalinus Clay to illustrate its applicability and highlight the key aspects. 展开更多
关键词 Triaxial test Saturation CONSOLIDATION UNDRAINED Opalinus Clay Clay shale
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Effect of structured nurse-patient conversation on preventing falls among patients in an acute care hospital:A mixed study
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作者 Kathrin Weber Susanne Knueppel Lauener +2 位作者 Mieke Deschodt Florian Grossmann RenéSchwendimann 《International Journal of Nursing Sciences》 CSCD 2024年第5期513-520,I0001,共9页
Objectives:Inpatient falls are a major patient safety issue in acute care hospitals.Multifactorial inhospital fall prevention programs have shown reductions in falls and related risks.One common element of successful ... Objectives:Inpatient falls are a major patient safety issue in acute care hospitals.Multifactorial inhospital fall prevention programs have shown reductions in falls and related risks.One common element of successful programs is active patient involvement.This study objective was to explore patients’and nurses’experiences with a structured intervention to foster patient involvement.Methods:This study was conducted between September 2020 and April 2021 in a university hospital neurological ward.The studied intervention consisted of a falls information leaflet,and a structured nurse-patient conversation about fall risk-reduction activities.Nurses were trained to deliver the intervention and supported throughout the study.Nurses’and patients’experiences regarding personal involvement,satisfaction,and confidence were surveyed and analyzed quantitatively and qualitatively.Results:Fifty-six patients recruited by ward nurses received the intervention.After receiving the intervention,patients reported high levels of satisfaction with the in-hospital fall prevention conversation.Twenty-one nurses indicated that they would use the leaflet and communication aid.Twenty-one nurses commented on intervention facilitators and barriers.More specific facilitators included their shared perception that“handing out the leaflet to patients was not problematic”and that the leaflet was seen as“applicable in many patient situations.”Their comments indicated two particularly prominent barriers to conducting the intervention in clinical practice:1)“finding the time for the implementation in the daily clinical routine and workload”and 2)“environmental factors like a noisy and busy atmosphere on the ward.”Conclusions:This study provides insights into a patient involvement intervention featuring a structured nurse-patient discussion about fall risks.The accompanying information leaflet and communication guide require adaptations to facilitate sustainable implementation into the hospital’s fall prevention program,but proved useful. 展开更多
关键词 CONVERSATION Fall prevention HOSPITAL LEAFLET Nurses Patient involvement Patient engagement
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Human induced pluripotent stem cell based in vitro models of the blood-brain barrier: the future standard?
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作者 Winfried Neuhaus 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第10期1607-1609,共3页
There is an urgent and tremendous need for human dis- ease models in drug development in order to improve pre- clinical predictability. In the case of brain disorders drugs have to cross the blood-brain barrier (BBB... There is an urgent and tremendous need for human dis- ease models in drug development in order to improve pre- clinical predictability. In the case of brain disorders drugs have to cross the blood-brain barrier (BBB) to enter the central nervous system (CNS). It was estimated that more than 95% of the drugs cannot cross the BBB. 展开更多
关键词 Human induced pluripotent stem cell based in vitro models of the blood-brain barrier:the future standard BBB
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Sentiment Analysis of Low-Resource Language Literature Using Data Processing and Deep Learning
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作者 Aizaz Ali Maqbool Khan +2 位作者 Khalil Khan Rehan Ullah Khan Abdulrahman Aloraini 《Computers, Materials & Continua》 SCIE EI 2024年第4期713-733,共21页
Sentiment analysis, a crucial task in discerning emotional tones within the text, plays a pivotal role in understandingpublic opinion and user sentiment across diverse languages.While numerous scholars conduct sentime... Sentiment analysis, a crucial task in discerning emotional tones within the text, plays a pivotal role in understandingpublic opinion and user sentiment across diverse languages.While numerous scholars conduct sentiment analysisin widely spoken languages such as English, Chinese, Arabic, Roman Arabic, and more, we come to grapplingwith resource-poor languages like Urdu literature which becomes a challenge. Urdu is a uniquely crafted language,characterized by a script that amalgamates elements from diverse languages, including Arabic, Parsi, Pashtu,Turkish, Punjabi, Saraiki, and more. As Urdu literature, characterized by distinct character sets and linguisticfeatures, presents an additional hurdle due to the lack of accessible datasets, rendering sentiment analysis aformidable undertaking. The limited availability of resources has fueled increased interest among researchers,prompting a deeper exploration into Urdu sentiment analysis. This research is dedicated to Urdu languagesentiment analysis, employing sophisticated deep learning models on an extensive dataset categorized into fivelabels: Positive, Negative, Neutral, Mixed, and Ambiguous. The primary objective is to discern sentiments andemotions within the Urdu language, despite the absence of well-curated datasets. To tackle this challenge, theinitial step involves the creation of a comprehensive Urdu dataset by aggregating data from various sources such asnewspapers, articles, and socialmedia comments. Subsequent to this data collection, a thorough process of cleaningand preprocessing is implemented to ensure the quality of the data. The study leverages two well-known deeplearningmodels, namely Convolutional Neural Networks (CNN) and Recurrent Neural Networks (RNN), for bothtraining and evaluating sentiment analysis performance. Additionally, the study explores hyperparameter tuning tooptimize the models’ efficacy. Evaluation metrics such as precision, recall, and the F1-score are employed to assessthe effectiveness of the models. The research findings reveal that RNN surpasses CNN in Urdu sentiment analysis,gaining a significantly higher accuracy rate of 91%. This result accentuates the exceptional performance of RNN,solidifying its status as a compelling option for conducting sentiment analysis tasks in the Urdu language. 展开更多
关键词 Urdu sentiment analysis convolutional neural networks recurrent neural network deep learning natural language processing neural networks
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Periodontal Ligament Stem Cells Reverse the High Glucose Level-Induced Inflammatory State of Macrophages
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作者 LIU Yun Xia DING Xiao Ling +3 位作者 TANG Shuai CUI Shu Yue LIU Jia Jia DING Gang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2022年第7期674-679,共6页
Periodontitis is a chronic infectious disease characterized by plaque biofilm as its main pathogenic factor;its clinical manifestations include gingival inflammation,alveolar bone resorption,attachment loss,and period... Periodontitis is a chronic infectious disease characterized by plaque biofilm as its main pathogenic factor;its clinical manifestations include gingival inflammation,alveolar bone resorption,attachment loss,and periodontal pocket formation,all of which eventually lead to tooth loss and seriously affect the quality of life of patients[1].This illness has a close relationship with blood sugar levels in patients with diabetes and is one of the most important complications of diabetes[2].Macrophages are an important part of host immune responses and exhibit powerful functions of identifying,phagocytizing,and removing bacteria;macrophage polarization is involved in the pathogenesis of periodontitis[3]. 展开更多
关键词 INFLAMMATION removing eventually
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Nicotine Weakens the Osteogenic Differentiation and Immune Regulation Capabilities of Periodontal Ligament Stem Cells
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作者 ZHANG Lu Dan CUI Shu Yue +2 位作者 CHENG Chen DING Xiao Ling DING Gang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2022年第4期375-379,共5页
Periodontitis is a chronic inflammatory disease resulting in the loss of periodontal tissues and ultimately teeth,thus posing a substantial public-health burden worldwide[1].With the widespread increase in mesenchymal... Periodontitis is a chronic inflammatory disease resulting in the loss of periodontal tissues and ultimately teeth,thus posing a substantial public-health burden worldwide[1].With the widespread increase in mesenchymal stem cell(MSC)therapy and the discovery of MSCs in periodontal ligaments[2],periodontal ligament stem cells(PDLSCs)have been used to reconstruct periodontal tissue and repair bone defects[2,3].Furthermore. 展开更多
关键词 LIGAMENT IMMUNE PERIODONTAL
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Environmental Monitoring in Museums Based on Wireless Sensor Network via Cell Phone
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作者 Laura Margarita Rodriguez Peralta Andrea Maria Mendes Abreu Lina Maria Pestana Leao de Brito 《通讯和计算机(中英文版)》 2014年第2期194-202,共9页
关键词 无线传感器网络 环境监测 博物馆 手机 连续监测 测量设备 应用程序 结构健康
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Microcalorimetric Study of Extruded Dog Food Containing Probiotic Micro-Organisms
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作者 Aram Kazarjan Natalja Kabanova Raivo Vilu 《Advances in Microbiology》 2012年第4期436-440,共5页
Extruded dry dog food products claimed to have a probiotic ingredient of Enterococcus faecium (NCIMB10415) in the commercial available formulations under the brand name of ProBiotic LIVE (Bacterfield S.A., Luxembourg)... Extruded dry dog food products claimed to have a probiotic ingredient of Enterococcus faecium (NCIMB10415) in the commercial available formulations under the brand name of ProBiotic LIVE (Bacterfield S.A., Luxembourg) were studied in the present work using a multichannel thermal activity monitor TAM III. Maximum specific growth rate, heat produced during different growth phases, and lag-phase duration were determined. The length of the lag-phase that can be used to determine the time necessary for the probiotic ingredient to restore its activity after consumption of probiotic containing extruded products was also measured. The calorimetric data confirmed the ability of the Enterococcus faecium to grow at the acidic pH conditions, modeling conditions of gastro-intestinal tract of dogs, and preserve its metabolic activity (viability) at the same level as at the neutral pH. The results obtained indicated that microcalorimetry was a precise and convenient tool for monitoring probiotic activity in complicated solid-state matrices. 展开更多
关键词 ENTEROCOCCUS FAECIUM Probiotic DOG FOOD MICROCALORIMETRY
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Proteome-Based Clustering Approaches Reveal Phylogenetic Insights into Amphistegina
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作者 Marleen Stuhr Bernhard Blank-Landeshammer +4 位作者 Achim Meyer Vera Baumeister Jörg Rahnenführer Albert Sickmann Hildegard Westphal 《Journal of Earth Science》 SCIE CAS CSCD 2022年第6期1469-1479,共11页
Foraminifera are highly diverse and have a long evolutionary history.As key bioindicators,their phylogenetic schemes are of great importance for paleogeographic applications,but may be hard to recognize correctly.The ... Foraminifera are highly diverse and have a long evolutionary history.As key bioindicators,their phylogenetic schemes are of great importance for paleogeographic applications,but may be hard to recognize correctly.The phylogenetic relationships within the prominent genus Amphistegina are still uncertain.Molecular studies on Amphistegina have so far only focused on genetic diversity within single species and suggested a cryptic diversity that demands for further investigations.Besides molecular sequencing-based approaches,different mass spectrometry-based proteomics approaches are increasingly used to give insights into the relationship between samples and organisms,especially as these do not require reference databases.To better understand the relationship of amphisteginids and test different proteomics-based approaches we applied de novo peptide sequencing and similarity clustering to several populations of Amphistegina lobifera,A.lessonii and A.gibbosa.We also analyzed the dominant photosymbiont community to study their influence on holobiont proteomes.Our analyses indicate that especially de novo peptide sequencing allows to reconstruct the relationship among foraminiferal holobionts,although the detected separation of A.gibbosa from A.lessonii and A.lobifera may be partly influenced by their different photosymbiont types.The resulting dendrograms reflect the separation in two lineages previously suggested and provide a basis for future studies. 展开更多
关键词 large benthic foraminifera de novo peptide sequencing tandem mass spectra clustering LC-MS/MS runs proteomics symbiont diversity PHYLOGEOGRAPHY Fragilariales
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Compound’s Pre-Screening of <i>Withania somnifera</i>, <i>Bacopa monnieri</i>and <i>Centella asiatica</i>Extracts
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作者 Steffi Witter Georg Arju +4 位作者 Marina Junusova Maria Kuhtinskaja Ago Samoson Raiker Witter Raivo Vilu 《Journal of Biosciences and Medicines》 2020年第9期80-98,共19页
Spectral fluorescence signature, Gas Chromatography-Mass Spectrometry and Liquid Chromatography-Mass Spectrometry for identification of chemical and bioactive compounds were applied to study the plant extracts of <... Spectral fluorescence signature, Gas Chromatography-Mass Spectrometry and Liquid Chromatography-Mass Spectrometry for identification of chemical and bioactive compounds were applied to study the plant extracts of <em>Withania somnifera</em>, <em>Centella asiatica </em>and <em>Bacopa monnieri </em>which are related to the possible treatment of mental diseases as Alzheimer, Parkinson and Depression. These plants are known for different positive phytotherapeutic effects on the human brain without negative post-, adverse or after effects to the treated individuals, and have been recommended in several medical studies. Therefore, we selected these plants for further analysis, based on the inhibition results of <em>in vitro</em> Amyloid Beta fibrillation tests made by previous measurements. With this study a first screening of the complex plant extract mixtures was performed, to get an initial overview about known and unknown ingredients. In all three plants, similar main compounds were identified, however in different quality and quantity. These may provide substantial information on which compound combinations might be mainly responsible for the positive effects and should be further investigated being responsible for reducing the fibrillation process of Amyloid Beta. 展开更多
关键词 Gas Chromatography-Mass Spectrometry Liquid Chromatography-Mass Spectrometry Principal Component Analysis Spectra Fluorescence Signature EXTRACTS Withania somnifera Bacopa monnieri Centella asiatica
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Ultrastructural Characteristics of Sheep and Horse Mesenchymal Stem Cells (MSCs)
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作者 Asuman Ozen Irem Gul Sancak +1 位作者 Brigitte Von Rechenberg Sabine Koch 《Microscopy Research》 2013年第3期17-23,共7页
In the present study, the morphological and ultrastructural characteristics of mesenchymal stem cells (MSCs) induced towards osteogenic, adipogenic, and chondrogenic lineages were investigated. The main objective of t... In the present study, the morphological and ultrastructural characteristics of mesenchymal stem cells (MSCs) induced towards osteogenic, adipogenic, and chondrogenic lineages were investigated. The main objective of this paper was to focus on the differentiation capacity of ovine [oMSCs] and equine MSCs [eMSCs]. Bone marrow [BM] MSCs were isolated from ovine and equine patients, expanded in monolayer culture and induced into osteogenic, adipogenic and chondrogenic differentiation. For chondrogenic differentiation, cells were cultured in micromass culture. Also, their ultrastructural phenotypes were studied by transmission electron microscopy [TEM]. This study was aimed to provide an indepth morphological description of BM-derived ovine and equine MSCs induced towards three lineages, it demonstrated that TEM analysis is useful in elucidating detailed structural information. 展开更多
关键词 ULTRASTRUCTURE MESENCHYMAL Stem Cells (MSCs) TEM Differentiation EQUINE OVINE
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Applicability of Strain Controlled Cyclic Tests for Short Fibre Reinforced Polymers
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作者 Andreas Primetzhofer Garbriel Stadler +1 位作者 Gerald Pinter Florian Grün 《Materials Sciences and Applications》 2019年第8期568-583,共16页
To develop parts, made of short glas fibre reinforced (sgfr) polymers for industrial purposes, a comprehensive material knowledge is necessary. Especially the material behaviour under cyclic loads has a great influenc... To develop parts, made of short glas fibre reinforced (sgfr) polymers for industrial purposes, a comprehensive material knowledge is necessary. Especially the material behaviour under cyclic loads has a great influence on the life time of parts. Parts are often used under complex load cases (stress state, temperature, ...), therefore it is indispensable to understand the effect of the main influence factors. High loads within load histories as well as stress concentrations can lead to plastic deformations. To cover this in an early stage of the development process, a closed simulation chain should be established. Therefore, the applicability of common material models (e.g. fatigue criteria according to Ramberg-Osgood) has to be studied first, the models have to be adapted or even new models have to be found for sgfr materials. This work focuses on the applicability of strain controlled cyclic tests for glass fibre reinforced polymers. Hereby the cyclic stress rearrangement in the low cycle regime of the S/N-curve can be described. Therefore, tests were performed on a 50 wt% sgfr partial aromatic polyamide. For the fatigue tests un-notched, injection moulded specimen were used. The tests show a principal applicability of strain controlled LCF-tests for sgfr polymers. 展开更多
关键词 Low CYCLE FATIGUE Life Time Prediction FIBRE Reinforced Polymer VISCO-ELASTIC Material Behaviour FATIGUE Design
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Termite Resistance of Heat-Treated Eucalyptus OSB Bonded with Eco-Friendly Castor Oil Adhesive
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作者 Estefani S.Sugahara Andre M.A.Dias +5 位作者 Fernanda D.Maffioletti Juarez B.Paes Andre L.Christoforo Edson C.Botelho Alfredo M.P.G.Dias Cristiane I.Campos 《Journal of Renewable Materials》 EI CAS 2024年第11期1911-1925,共15页
Over the last decade,the oriented strand board(OSB)market presented meaningful growth.However,as a woodbased product,because of its anatomical structure and chemical composition,OSB can be damaged by biodeterioration ... Over the last decade,the oriented strand board(OSB)market presented meaningful growth.However,as a woodbased product,because of its anatomical structure and chemical composition,OSB can be damaged by biodeterioration agents.Given that,the biodeterioration of OSB panels must be investigated to improve its durability.In this way,this work analyses the biological resistance against termites(Cryptotermes brevis and Nasutitermes corniger)of heat-treated OSB panels made with Eucalyptus wood glued with vegetable-based polyurethane-an ecofriendly and sustainable adhesive derived from castor oil.Various panels were produced with different layers compositions(face:core:face of 25:50:25 and 30:40:30)in wood mass proportion and were submitted to postproduction heat treatment(at 175℃ and 200℃)replacing the use of chemical insecticides.The influence of the layers variation and heat treatment temperature were evaluated,and these results were compared with commercial panels(made from pinus wood with insecticide).The results showed that the heat treatment did not improve the resistance against termite attack.However,all the experimental panels presented a satisfactory performance that was compatible with the commercial panels produced with insecticide available in the Brazilian market.The combination of Eucalyptus wood and castor oil adhesive to produce OSB,in any variation of layer composition,demonstrated natural resistance against termite attack compatible with the commercial panels,even without using chemical additives to increase durability. 展开更多
关键词 Alternative raw materials BIODETERIORATION OSB panel castor oil adhesive wood products
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