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Polyelectrolyte Complexes between Hyperbranched and Linear Polysaccharides: Fucoidan/Chitosan

Chinese Journal of Polymer Science 2024年第4期42卷 468-479页

作者： Ekaterina R.Gasilova Daria n.Poshina Aleksandra O.Sitnikova natalia n.Saprykina Yury A.Skorik Institute of Macromolecular Compounds of the Russian Academy of Sciences Bolshoi VO 31St.Petersburg199004Russian Federation

Polyelectrolyte complexes(PECs)of hyperbranched(HB)and linear polysaccharides are promising as more effective encapsulation agents compared to PECs formed by linear *** investigated the PECs between the HB anionic polysaccharide fucoidan(FUC)and the cationic linear polysaccharide chitosan(CS).The FUC had a molecular weight(MW)of 30×*** PECs were prepared in three solvents(water,0.01 and 0.1 mol/L acetic acid)with CS of MW of 15,110 and 170 kDa,and deacetylation degrees(DDA)of 70%and 97%.The structures of the PECs and the initial FUC were investigated by multi-angle static and dynamic light *** the FUC contained 18 wt%of—OSO3 groups and 5 wt%of uronic acid units,it was a“strong-weak”copolyanion,so the HB macromolecules of the FUC formed nanogel particles in 0.1 mol/L AcOH and open branched structures in water,as confirmed by the Kratky *** mixing the solutions of original components,the PEC structures underwent an equilibration period,the duration of which increased with the MW of *** the charge stoichiometry was approached,the PECs shrank;the fractal dimension approached unity,indicating the side-by-side packing of adjacent FUC branches with the help of *** aggregation in the vicinity of the charge compensation was hardly observed,as it occurred in a very narrow *** PEC content at theζ-potential inversion depended on solvents’pH and the DDA of *** the extreme case of core-shell PECs in 0.1 mol/L AcOH,obtained by mixing FUC nanogels with the solutions of high MW CS of 97%DDA,the protruding tails of CS formed a positively charged shell in the whole range of FUC content(10 wt%nning electron microscopy and atomic force microscopy images of dried samples were discussed in relation to the light scattering results.

关键词： Polyelectrolyte complexes Chitosan Hyperbranched fucoidan Light scattering

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Double-check in Lizard Age Estimation:Use of Phalanx Bone and Keratin Claw Sheath Lamellas

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Asian Herpetological Research 2024年第1期15卷 59-61页

作者： Eduard GALOYAn natalia SOPILKO Anna KOVALYEVA Anna CHAMKInA A.n.Severtsov Institute of Ecology and Evolution Moscow 119071Russia Lomonosov Moscow State University Leninskie Gori 1Moscow 119991Russia

Dear Editor,The problem of age estimation in amphibians and reptiles with annual fluctuations of growth pattern has been considered to be mostly solved since the skeletochronological method was introduced(Kleinenberg and Smirina,1969).This method is based on counting the number of lines of arrested growth(LAGs)—cyclical growth marks that are usually formed annually and characterized by different optical aspects within the tubular bones.

关键词： estimation method usual

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Design of Biologically Active Macromolecular Ligands and Their Luminescent Complexes with Terbium Ions

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Chinese Journal of Polymer Science 2024年第5期42卷 604-611,I0007页

作者： Tatiana n.nekrasova Andrei I.Fischer natalia A.nesterova Anatoliy V.Dobrodumov Anzhelika V.Garshinina Olga D.Shuvaeva natalya V.Zakharova Evgenii F.Panarin Institute of Macromolecular Compounds Russian Academy of Sciences31 Bolshoy pr.St Petersburg199004Russia Smorodintsev Research Institute of Influenza Russian Ministry of Health15/17 ul.prof.PopovaSt Petersburg197376Russia

Water-soluble copolymers of p-methacrylamidobenzoic acid(MABA)with neutral comonomers(n-vinylpyrrolidone(VP),n-methyl-n-vinylacetamide(MVAA),n-methacryloyl glucosamine(MAG))and anionic comononer sodium styrene sulfonate(naSS)were synthesized by radical *** interactions between the prepared copolymers and Tb^(3+)ions in aqueous solutions were studied;the significant influence of chemical structure of a comonomer on luminescence intensity of Tb^(3+)complexes with the copolymers was *** luminescence intensity of Tb^(3+)complexes with the copolymers containing n-vinylamide units(VP,MVAA)is three times more intense than that observed for the complexes between Tb^(3+)and MAG-containing *** the case of naSS-containing copolymers,the luminescence intensity is controlled by the values of binding constants between Tb^(3+)and MABA and the content of MABA units in a *** studied copolymers and their complexes with Tb^(3+)have low cytotoxicity and a pronounced antiviral activity against human respiratory syncytial virus.

关键词： Luminescence Water-soluble copolymers Lanthanide complexes Antiviral activity Cytotoxicity

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Organic Compounds Possessing the Plastic Crystalline Phase: Calculation of Their Fusion Enthalpies

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International Journal of Organic Chemistry 2024年第3期14卷 93-106页

作者： Mikhail Yu. Gorbachev natalia n. Gorinchoy Institute of Chemistry Moldova State University Chiinu Republic of Moldova

For the first time, for different organic and inorganic compounds possessing the plastic crystalline phase, a new semiempirical equation describing dependence of their fusion enthalpies on such physico-chemical quantities as normal melting temperature, surface tension, molar volume and critical molar volume is received on the base of the principle of corresponding states and the energy equipartition theorem. Moreover, the proposed equation allows one to take into account the particularities of one-particle molecular rotation in the plastic crystalline phase.

关键词： Fusion Enthalpies Calculation Organic Compounds Inorganic Compounds Plastic Crystalline Phases

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Early neoproterozoic Granite-Gneisses of the Junggar Alataw(Southeastern Kazakhstan):Age,Petrogenesis and Tectonic Implications

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 67-82页

作者： nadezhda KAnYGInA Andrey TRETYAKOV Dmitriy ALEXEIEV Kirill DEGTYAREV Anfisa SKOBLEnKO natalia SOLOSHEnKO Boris ERMOLAEV Geological Institute Russian Academy of SciencesMoscow 119017Russia A.n.Zavaritsky Institute of Geology and Geochemistry Ural Branch of the Russian Academy of SciencesYekaterinburg 620016Russia

The combined petrographic,petrological,geochemical and geochronological study of the neoproterozoic gneisses of the Sarychabyn and Baskan complexes of the Junggar Alataw of South Kazakhstan elucidate the Precambrian tectonic evolution of the Aktau–Yili *** is one of the largest Precambrian crustal blocks in the western Central Asian orogenic *** U-Pb single-grain zircon ages indicate that granite-gneisses formed from the same source and crystallised in the early neoproterozoic ca.930–920 *** chemical composition of gneisses corresponds to A2-type *** whole-rock nd isotopic characteristics(εnd(t)=−4.9 to−1.0 and Tnd(DM-2st)=1.9 to 1.7 Ga)indicate the involvement of Paleoproterozoic crustal rocks in magma *** neoproterozoic ca.930–920 Ma A-type granitoids in the Aktau–Yili terrane of South and Central Kazakhstan might reflect within-plate magmatism adjacent to the collisional belt or a local extension setting in back-arc areas of the continental arc.

关键词： granitoid magmatism geochemistry geochronology Sm-nd isotope systematics neoproterozoic Junggar Alataw Kazakhstan Central Asian orogenic belt

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From non-scattering to super-scattering with Mie-tronics

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Photonics Research 2024年第4期12卷 608-624页

作者： HOOMAn BARATI SEDEH natalia M.LITCHInITSER Department of Electrical and Computer Engineering Duke UniversityDurhamNorth Carolina 27708USA

Electric anapoles, arising from the destructive interference of primitive and toroidal electric dipole moments, have recently emerged as a fundamental class of non-scattering sources. On the other hand, super-scattering states represent the opposite regime wherein the scattering cross-section of a subwavelength particle exceeds the single-channel limit, leading to a strong scattering behavior. Here, we demonstrate that the interplay between the topology of light and the subwavelength scatterer can lead to these two opposite responses within an isolated alldielectric meta-atom. In particular, we present the emergence of a new non-scattering state, referred to as hybrid anapole, which surpasses conventional electric dipole anapoles by achieving a remarkable 23-fold enhancement in the suppression of far-field radiation and almost threefold enhancement in the confinement of electromagnetic energy inside the meta-atom. We also explore the role of particle orientation and its inversion symmetry in the scattering response and predict the possibility of switching between non-scattering and super-scattering states within the same platform. The presented study elucidates the role of light and matter topologies in the scattering response of subwavelength meta-atoms, uncovering two opposite regimes of light-matter interaction and opening new avenues in applications such as nonlinear optics and spectroscopy.

关键词： spectroscopy opposite dipole

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Passive seismic investigation of intraplate earthquakes epicentral zones in the north of Russia as one of the ways to understand their source mechanics

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Journal of Earth Science 2024年

作者： Konstantin Danilov Galina Antonovskaya Irina Basakina Eugenia Shakhova natalia Kapustian n.Laverov Federal Center for Integrated Arctic Research of the Ural Branch of the Russian Academy of Sciences

Studying the inner structure of intraplate earthquakes originating in aseismic areas， which are poorly covered by seismic networks or as historical earthquakes is usually the only way to get knowledge about their source mechanisms that is partially important to deeper understand intraplate geodynamics. The epicentral zones of earthquakes are situated in hard-to-reach areas， so， using active seismic methods for such purposes is unreasonable or even impossible because of high cost and logistical difficulties. We are presenting a way to join using different passive seismic methods， which allows us to get sufficient information about geological environment structure for such task solutions. As an example， we investigated the inner structure of platform earthquake epicentral zone originated up north of Russia. We used four passive seismic methods: microseismic sounding method， passive seismic interferometry， HVSR method， and microseismic activity method. We show that passive seismic data， recoded in the same installation and processed by these different methods， can provide sufficient information about structure of studied environment， needed to explain source mechanism. In sum， the hypocenter zone is presented by intersection of vertical faults and a lateral fractured zone in the middle crust. Results were confirmed by comparison with results by active seismic methods.

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56 Years of the Marburg Virus—A Review of Therapeutics

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Open Journal of Epidemiology 2024年第2期14卷 273-283页

作者： Michael M. Toza Emmanuel Imangolwa natalia Shakela Ferdinand ndubi Hanzoma Hatwiko Christabel n. Hikaambo Department of Pharmacy School of Health Sciences University of Zambia Lusaka Zambia Department of Biology Chemistry and Physics School of Health and Applied Sciences Namibia University of Science and Technology Windhoek Namibia Department of Pharmaceutical Chemistry and Pharmaceutics School of Pharmacy Kabarak University Nakuru Kenya Department of Physiological Sciences School of Medicine and Health Sciences Mulungushi University Livingstone Zambia

Background: The Marburg virus (MARV) is the causative agent of Marburg virus disease (MVD). This filovirus first appeared in 1967 and has since caused several outbreaks with case fatality rates between 23% and 90%. The earliest cases of MVD are thought to be caused by exposure to an infected animal, either a reservoir host (some bat species, e.g., Rousettus aegyptiacus) or a spill-over host, such as non-human primates. The virus is spread between people by direct contact with blood or other bodily fluids (including saliva, sweat, faeces, urine, tears, and breast milk) from infected individuals. Despite the high fatality rate, the Marburg virus has no vaccine or drug treatment. Recent outbreaks of the virus in 2023 in Tanzania and Equatorial Guinea have reignited the need to develop effective therapeutics, especially in the wake of the COVID-19 pandemic. Purpose: This review seeks to highlight the drug discovery efforts aimed at developing vaccines or possible treatments as potential therapeutics. Several existing antiviral agents are being probed, and vaccines are in pre-clinical and clinical stages. natural products are also an important source of possible drugs or lead compounds and when coupled with computational techniques, these strategies offer possible therapeutics for the Marburg virus, especially in Africa, which has a high disease burden. Methods: Using the search engines Google Scholar and PubMed;keywords e.g. Marburg virus, Marburg treatments, Marburg virus drug discovery were utilized. Several results were yielded, and articles published in recent years were accepted into the final *** and Conclusion: This study shows there is a growing interest in therapeutics for the Marburg virus, especially with the recent outbreaks and pandemic preparedness. Initiatives that to support vaccine development and access like the MARVAC consort time are critical to fighting this public health threat.

关键词： Marburg Virus Vaccines Antivirals Viruses Drug Discovery

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Pancreatic neuroendocrine tumors:Are tumors smaller than 2 cm truly indolent?

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1756-1762页

作者： Sergio Hoyos Pablo Posada-Moreno natalia Guzman-Arango Romario Chanci-Drago Jaime Chavez Alvaro Andrés-Duarte Santiago Salazar-Ochoa Hepatobilary and Liver Transplant Unit Hospital Pablo Tobon Uribe and Gastrohepathology Group Universidad de AntioquiaMedellin 050034AntioquiaColombia Department of General Surgery Universidad Pontificia BolivarianaMedellín 050034AntioquiaColombia

BACKGROUnD Pancreatic neuroendocrine tumors(PnETs)are relatively rare but rank as the second most common pancreatic *** can be functional,causing early metabolic disturbances due to hormone secretion,or non-functional and diagnosed later based on tumor size-related *** diagnoses of PnETs under 2 cm in size have sparked debates about their management;some practitioners advocate for surgical removal and others suggest observation due to the tumors’lower potential for ***,it is unclear whether managing these small tumors expectantly is truly *** To evaluate poor prognostic factors in PnETs based on tumor size(>2 cm orn surgically treated *** This cohort study included 64 patients with PnETs who underwent surgical resection between 2006 and 2019 at a high-complexity reference hospital in Medellín,*** assess patient survival,quarterly follow-ups were conducted during the first year after surgery,followed by semi-annual con-sultations at the hospital's hepatobiliary surgery *** variables were described using absolute and relative frequencies,and quantitative variables were expressed using measures of central tendency and their corresponding measures of *** The presence of lymph node involvement,neural involvement,and lymphovascular invasion were all associated with an increased risk of mortality,with hazard ratios of 5.68(95%CI:1.26–25.61,P=0.024),6.44(95%CI:1.43–28.93,P=0.015),and 24.87(95%CI:2.98–207.19,P=0.003),*** involvement and lymphovascular invasion were present in tumors smaller than 2 cm in diameter and those larger than 2 cm in *** recurrence rates between the two tumor groups were furthermore similar:18.2%for tumors smaller than 2 cm and 21.4%for tumors larger than 2 *** survival was additionally comparable between the two tumor *** Tumor size does not dictate prognosis;lymph node and lymphovascular involvement a

关键词： neuroendocrine tumor Pancreatic neoplasm Pancreas Pancreatic neuroendocrine neoplasm Pancreatic neuroendocrine tumors

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Large-scale genome-wide SnP analysis reveals the rugged(and ragged)landscape of global ancestry,phylogeny,and demographic history in chicken breeds

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第4期25卷 324-340页

作者： natalia V.DEMEnTIEVA Yuri S.SHCHERBAKOV Olga I.STAnISHEVSKAYA Anatoly B.VAKHRAMEEV Tatiana A.LARKInA Artem P.DYSIn Olga A.nIKOLAEVA Anna E.RYABOVA Anastasiia I.AZOVTSEVA Olga V.MITROFAnOVA Grigoriy K.PEGLIVAnYAn natalia R.REInBACH Darren K.GRIFFIn Michael n.ROMAnOV Russian Research Institute of Farm Animal Genetics and Breeding-Branch of the L.K.Ernst Federal Research Centre for Animal Husbandry.Pushkin St.Petersburg196601Russia School of Biosciences University of KentCanterburyCT27NJUK L.K.Ernst Federal Research Center for Animal Husbandry DubrovitsyPodolskMoscow Oblast142132Russia

The worldwide chicken gene pool encompasses a remarkable,but shrinking,number of divergently selected breeds of diverse *** study was a large-scale genome-wide analysis of the landscape of the complex molecular architecture,genetic variability,and detailed structure among 49 *** populations represent a significant sample of the world's chicken breeds from Europe(Russia,Czech Republic,France,Spain,UK,etc.),Asia(China),north America(USA),and Oceania(Australia).Based on the results of breed genotyping using the Illumina 60K single nucleotide polymorphism(SnP)chip,a bioinformatic analysis was carried *** included the calculation of heterozygosity/homozygosity statistics,inbreeding coefficients,and effective population *** also included assessment of linkage disequilibrium and construction of phylogenetic *** multidimensional scaling,principal component analysis,and ADMIXTURE-assisted global ancestry analysis,we explored the genetic structure of populations and subpopulations in each *** overall 49-population phylogeny analysis was also performed,and a refined evolutionary model of chicken breed formation was proposed,which included egg,meat,dual-purpose types,and ambiguous *** a large-scale survey of genetic resources in poultry farming using modern genomic methods is of great interest both from the viewpoint of a general understanding of the genetics of the domestic chicken and for the further development of genomic technologies and approaches in poultry *** general,whole genome SnP genotyping of promising chicken breeds from the worldwide gene pool will promote the further development of modern genomic science as applied to poultry.

关键词： Chicken genome diversity Single nucleotide polymorphism(SnP)analysis Gene pool Global ancestry Phylogeny Demographic history

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