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Recent Advances in Catalytic Carbonylation Reactions in Alternative Reaction Media

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Chinese Journal of Chemistry 2024年第4期42卷 406-429页

作者： csaba Árvai László T.Mika Department of Chemical and Environmental Process Engineering Faculty of Chemical Technology and BiotechnologyBudapest University of Technology and EconomicsMűegyetem rkp.3H-1111 BudapestHungary

Since the discovery of the hydroformylation(oxo-synthesis or Roelen reaction)and the Reppe-reaction,the transition metal-catalyzed carbonylation reactions,providing versatile,facile,and even atom-economic methods for the selective incorporation of C=O functionality to various skeletons,have gained tremendous importance in synthetic organic chemistry from laboratories to industrial *** carbonylation of carbon-carbon multiple bonds,aromatic halides,triflates,etc.,in the presence of various nucleophiles has led the way to produce aldehydes,carboxylic acids,esters,amides,etc.,in the fine chemical ***,these protocols usually proceed in conventional,fossil-based,and usually toxic reaction ***,several attempts have been directed to developing efficient carbonylation methods in alternative,less harmful,non-fossil-based and even in renewable reaction *** this review,we overview the recent applications of alternative solvents such as water,biomass-based alcohols,γ-valerolactone(GVL),2-methyltetrahydrofuran(2-MeTHF),ionic liquids(ILs),deep eutectic solvents(DES),alkyl levulinates,limonene,α-pinene,and dimethyl carbonate as well as fluorous media to improve efficiency,safety and environmentally benign nature of carbonylation protocols.

关键词： Carbonylation Catalysis Solvents Green chemistry Carbon monoxide Transition metals Homogeneous catalysis Palladium

Niche differentiation among facultative filter feeders: Insights from invasive Ponto-Caspian mysids

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Current Zoology 2024年第4期70卷 513-521页

作者： Péter Borza Varsha Rani csaba F.Vada Institute of Aquatic Ecology Centre for Ecological ResearchKarolina ut 29.1113 BudapestHungary Doctoral School of Biology Institute of BiologyEotvos Lorand UniversityPazmany Péter sétany 1/C1117 BudapestHungary

The degree of dietary specialization has a fundamental impact on the ecological function and interactions of suspension *** niche differentiation by food particle size is common among obligate suspension feeders,its role is not evident in facultative *** this study,we aimed at providing new insights on the matter by focusing on sympatric mysid *** mysids use different mechanisms for raptorial and filter-feeding,they represent a more adequate model system than for example,the more extensively studied *** made morpholog-ical measurements on the 4 coexisting invasive Ponto-Caspian mysid species to determine the areas and mesh sizes of their *** also quantified their clearance rates on the microalga Cryptomonas *** a laboratory experiment to reveal how morphological differences manifest in their overall filtering *** found relatively small but consistent differences in the primary filter area among the species,indicating that morphological constraints due to the enclosed position of the setae might limit the possibility for *** primary filter mesh sizes were small in all 4 species(0.69-2.73μm)with moderate but consistent intraspecific differences,suggesting that the benefit of being able to capture small particles might outweigh the pressure for *** observed clearance rates were in accordance with the morphological characteristics of the species,highlighting that auxiliary filters(present in one of the species,Limnomysis benedeni)are needed to increase filtering capacity *** study confirmed that food particle size can contribute to the niche differentiation of facultative filter feeders,but also indicated that they can tolerate a higher overlap than obligate *** observed differences were related to the habitat preferences and predatory potentials of the species,suggesting that complementarity among the different niche axes might further facilitate theircoexistence.

关键词： clearance rate coexistence filter area filtermesh size.

Methionine sources and genotype affect embryonic intestinal development, antioxidants, tight junctions, and growth-related gene expression in chickens

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Animal Nutrition 2024年第1期16卷 218-230页

作者： James K.Lugata Sawadi F.Ndunguru Gebrehaweria K.Reda Xénia E.Ozsváth Eszter Angyal Levente Czeglédi Gabriella Gulyás Renáta Knop János Oláh Zoltán Mészár Rita Varga Brigitta Csernus csaba szabó Department of Animal Nutrition and Physiology Faculty of Agriculture and Food Sciences and Environmental Management University of Debrecen Faculty of Agriculture and Food Sciences and Environmental Management Doctoral School of Animal Science University of Debrecen Department of Animal Husbandry Faculty of Agriculture and Food Sciences and Environmental Management University of Debrecen Department of Evolutionary Zoology and Human Biology Faculty of Science and Technology University of Debrecen Institutes for Agricultural Research and Educational Farm University of Debrecen Department of Anatomy Histology and Embryology Faculty of Medicine University of Debrecen

Methionine(Met) is an essential and first limiting amino acid in the poultry diet that plays a significant role in chicken embryonic development and growth. The present study examined the effect of in ovo injection of DL-Met and L-Met sources and genotypes on chicken embryonic-intestinal development and health. Fertilized eggs of the two genotypes, TETRA-SL layer hybrid(TSL)—commercial layer hybrid and Hungarian Partridge colored hen breed(HPC)—a native genotype, were randomly distributed into four treatments for each genotype. The treatment groups include the following: 1) control non-injected eggs(NoIn); 2) saline-injected(SaIn); 3) DL-Met injected(DLM); and 4) L-Met injected(LM). The in ovo injection was carried out on 17.5 d of embryonic development; after hatching, eight chicks per group were sacrificed, and the jejunum was extracted for analysis. The results showed that both DLM and LM groups had enhanced intestinal development as evidenced by increased villus width, villus height, and villus area(P < 0.05) compared to the control. The DLM group had significantly reduced crypt depth, glutathione(GSH) content, glutathione S-transferase 3 alpha(GST3), occludin(OCLN) gene expression and increased villus height to crypt depth ratio in the TSL genotype than the LM group(P < 0.05). The HPC genotype has overexpressed insulin-like growth factor 1(IGF1) gene, tricellulin(MD2), occludin(OCLN),superoxide dismutase 1(SOD1), and GST3 genes than the TSL genotype(P < 0.05). In conclusion, these findings showed that in ovo injection of Met enhanced intestinal development, and function, with genotypes responding differently under normal conditions. Genotypes also influenced the expression of intestinal antioxidants, tight junction, and growth-related genes.

关键词： DL-Methionine L-Methionine In ovo injection Intestinal development Poultry

Holmes-Adie syndrome, autoimmune hepatitis and celiac disease: A case report

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World Journal of Gastroenterology 2006年第9期12卷 1485-1487页

作者： Timea Csak Aniko Folhoffer Andrea Horvath Judit Halász csaba Diczházi Zsuzsa Schaff Ferenc szalay Department of Medicine Semmelweis University BudapestHungary Department of Pathology Semmelweis University BudapestHungary

A 35-year-old female patient presented with the following symptoms of Holmes-Adie syndrome： photophobia, enlargement of the left pupil unresponsive to light, Achilles areflexia. The pilocarpine test was positive. No tumor or other neurological abnormality was found. She had a 19-year history of autoimmune hepatitis. Flares up were observed following each 3 deliveries. At age of 31 she presented with diarrhea and weight loss. Abdominal tumor was detected by ultrasound. The surgically removed tumor was histologically a benign mesenteric multicystic lymphangioma. Simultaneously, celiac disease was diagnosed. Gluten-free diet resulted in a significant improvement of celiac disease, but not of autoimmune hepatitis. Autonomic neuropathy was proven by standard cardiovascular tests. The patient was a homozygous carrier for HLA DQ2 antigen characteristic for celiac disease and heterozygous for HLA DR3 B8 frequent in autoimmune liver diseases. Our novel observation on association of Holmes-Adie syndrome with autoimmune hepatitis and celiac disease is suggestive for a common immunological background for all three entities present in a patient with mesenteric multicystic lymphangioma.

关键词： Holmes-Adie syndrome Autoimmune hepatitis Celiac disease Mesenteric lymphangioma Autonomic neuropathy

Single-cell transcriptome profiling of human HSCs during development:new insights into HSC ontogeny

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Signal Transduction and Targeted Therapy 2023年第3期8卷 877-878页

作者： Edgar Grinstein csaba Mahotka Department of Hematology Oncology and Clinical ImmunologyMedical FacultyHeinrich Heine UniversityDüsseldorfGermany Institute of Pathology Medical FacultyHeinrich Heine UniversityDüsseldorfGermany

A study recently published in Nature reported a single-cell transcriptome map of human hematopoietic stem cells(HSCs)and a gene expression signature that distinguishes nascent HSCs from non-HSCs during prenatal development.1 This transcriptome map provides an important tool for further elucidation of human HSC ontogeny and could also serve as a guide for generation of transplantable HSCs ex vivo,1 to widen the therapeutic application of HSCs.

关键词： HSCs transcriptome hematopoietic

The Importance of Flapping Kinematic Parameters in the Facilitation of the Different Flight Modes of Dragonflies

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Journal of Bionic Engineering 2021年第2期18卷 419-427页

作者： Xiaohui Liu csaba Hefler Wei Shyy Huihe Qiu Department of Mechanical and Aerospace Engineering The Hong Kong University of Science and TechnologyHong Kong SARChina

To better understand dragonflies’remarkable flapping wing aerodynamic performance,we measured the kinematic parameters of the wings in two different flight modes(Normal Flight Mode(NFM)and Escape Flight Mode(EFM)).When the specimens switched from normal to escape mode the flapping frequency was invariant,but the stroke plane of the wings was more horizontally *** flapping of both wings was adjusted to be more ventral with a change of the pitching angle that resulted in a larger angle of attack during downstroke and smaller during upstroke to affect the flow directions and the added mass ***,the phasing between the fore and hind pair of wings varies between two flight modes,which affects the wing-wing interaction as well as body *** is found that the momentum stream in the wake of EFM is qualitatively different from that in *** change of the stroke plane angle and the varied pitching angle of the wings diverts the momentum downwards,while the smaller flapping amplitude and less phase difference between the wings compresses the momentum *** seems that in order to achieve greater flight maneuverability a flight vehicle needs to actively control positional angle as well as the pitching angle of the flapping wings.

关键词： wing kinematics flight mode dragonfly flight aerodynamics

Insight into the antifungal mechanism of Neosartorya fischeri antifungal protein

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Protein & Cell 2015年第7期6卷 518-528页

作者： Mate Viragh Annamaria Marton csaba Vizier Liliana Toth csaba Vagvolgyi Florentine Marx Laszlo Galgoczy Department of Microbiology Faculty of Science and Informatics University of Szeged Szeged Hungary Institute of Biochemistry Biological Research Centre Hungarian Academy of Sciences Szeged Hungary Division of Molecular Biology Biocenter Innsbruck Medical University Innsbruck Austria

Small, cysteine-rich, highly stable antifungal proteins secreted by filamentous Ascomycetes have great po- tential for the development of novel antifungal strate- gies. However, their practical application is still limited due to their not fully clarified mode of action. The aim of this work was to provide a deep insight into the anti-fungal mechanism of Neosartorya fischeri antifungal protein （NFAP）, a novel representative of this protein group. Within a short exposure time to NFAP, reduced cellular metabolism, apoptosis induction, changes in the actin distribution and chitin deposition at the hyphal tip were observed in NFAP-sensitive Aspergillus nidulans. NFAP did show neither a direct membrane disrupting- effect nor uptake by endocytosis. Investigation of A. nidulans signalling mutants revealed that NFAP acti- vates the cAMP/protein kinase A pathway via G-protein signalling which leads to apoptosis and inhibition of polar growth. In contrast, NFAP does not have any in- fluence on the cell wall integrity pathway, but an un- known cell wall integrity pathway-independent mitogen activated protein kinase A-activated target is assumed to be involved in the cell death induction. Taken to- gether, it was concluded that NFAP shows similarities, but also differences in its mode of antifungal action compared to two most investigated NFAP-related pro-teins from Aspergillus giganteus and Penicillium chrysogenum.

关键词： Neosartorya fischeri antifungal protein,Aspergillus nidulans cAMP/Pka signalling Pkc/Mpksignalling antifungal mechanism

Bone disorders in experimentally induced liver disease in growing rats

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World Journal of Gastroenterology 2005年第45期11卷 7169-7173页

作者： Viktória Ferencz csaba Horváth Béla Kári János Gaál szilvia Mészáros Zsuzsanna Wolf Dalma Heged(?)s Andrea Horváth Anikó Folhoffer Ferenc szalay 1st Department of Internal Medicine Department of Diagnostic Radiology and Oncotherapy Department of Polymer Engineering and Textile Technology

AIM： To investigate the change of bone parameters in a new model of experimentally induced liver cirrhosis and hepatocellular carcinoma （HCC） in growing rats. METHODS： Fischer-344 rats （n = 55） were used. Carbon tetrachloride （CCh）, phenobarbital （PB）, and a single diethylnitrosamine （DEN） injection were used. Animals were killed at wk 8 and 16. Bone mineral content, femoral length, cortical index （quotient of cortical thickness and whole diameter） and ultimate bending load （Fmax） of the femora were determined. The results in animals treated with DEN＋PB＋CCh （DPC, n = 21） were com- pared to those in untreated animals （UNT, n = 14） and in control group treated only with DEN＋PB （DP, n = 20）. RESULTS： Fatty liver and cirrhosis developed in each DPC-treated rat at wk 8 and HCC was presented at wk 16. No skeletal changes were found in this group at wk 8, but each parameter was lower （P〈0.05 for each） at wk 16 in comparison to the control group. Neither fatty liver nor cirrhosis was observed in DP-treated animals at any time point. Femoral length and Fmax values were higher （P〈0.05 for both） in DP-treated animals at wk 8 compared to the UNT controls. However, no difference was found at wk 16. CONCLUSION： Experimental liver cirrhosis and HCC are accompanied with inhibited skeletal growth, reduced bone mass, and decreased mechanical resistance in growing rats. Our results are in concordance withthe data of other studies using different animal models. A novel finding is the transiently accelerated skeletal growth and bone strength after a 8-wk long phenobarbital treatment following diethylnitrosamine injection.

关键词： Bone disorder Bone mineral content Mechanical resistance Experimental liver cirrhosis Growingrat

Effects of aspect ratio on flapping wing aerodynamics in animal flight

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Acta Mechanica Sinica 2014年第6期30卷 776-786页

作者： Jun-Jiang Fu csaba Hefler Hui-He Qiu Wei Shyy Department of Mechanical and Aerospace Engineering The Hong Kong University of Science & Technology

Morphology as well as kinematics is a critical determinant of performance in flapping *** understand the effects of the structural traits on aerodynamics of bioflyers,three rectangular wings with aspect ratios（AR）of1,2,and 4 performing hovering-like sinusoidal kinematics at wingtip based Reynolds number of 5 300 are experimentally *** structures on sectional cuts along the wing span are *** K-H instability is found on the leading edge vortex of wings with higher aspect *** bursting only appears on the outer spanwise locations of high-aspect-ratio *** vortex bursting on high-aspect-ratio wings is perhaps one of the reasons why bio-flyers normally have low-aspect-ratio *** analysis exhibits larger dimensionless circulation of the leading edge vortex（LEV）over higher aspect ratio wings except when vortex bursting *** average dimensionless circulation of AR1 and AR2 along the span almost equals the dimensionless circulation at the 50%*** flow structure and the circulation analysis show that the sinusoidal kinematics suppresses breakdown of the LEV compared with simplified flapping kinematics used in similar *** Reynolds number effect results on AR4 show that in the current Re range,the overall flow structure is not sensitive to Reynolds number.

关键词： Aspect ratio Aerodynamics Leading edge vortex Flapping wing