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Brain-derived neurotrophic factor signaling in the neuromuscular junction during developmental axonal competition and synapse elimination

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neural Regeneration Research 2025年第2期20卷 394-401页

作者： Josep Tomàs Víctor Cilleros-Mañé Laia Just-Borràs Marta Balanyà-Segura aleksandra Polishchuk Laura nadal Marta Tomàs Carolina Silvera-Simón Manel M.Santafé Maria A.Lanuza Unitat d’Histologia i neurobiologia(UHneurob) Facultat de Medicina i Ciències de la SalutUniversitat Rovira i VirgiliReusSpain

During the development of the nervous system,there is an overproduction of neurons and *** competition between neighboring nerve endings and synapses performing different activity levels leads to their elimination or *** have extensively studied the involvement of the brain-derived neurotrophic factor-Tropomyosin-related kinase B receptor neurotrophic retrograde pathway,at the neuromuscular junction,in the axonal development and synapse elimination process versus the synapse *** purpose of this review is to describe the neurotrophic influence on developmental synapse elimination,in relation to other molecular pathways that we and others have found to regulate this *** particular,we summarize our published results based on transmitter release analysis and axonal counts to show the different involvement of the presynaptic acetylcholine muscarinic autoreceptors,coupled to downstream serine-threonine protein kinases A and C(PKA and PKC)and voltage-gated calcium channels,at different nerve endings in developmental *** dynamic changes that occur simultaneously in several nerve terminals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the mechanisms of specific *** describe an activity-dependent balance(related to the extent of transmitter release)between the presynaptic muscarinic subtypes and the neurotrophin-mediated TrkB/p75nTR pathways that can influence the timing and fate of the competitive interactions between the different axon *** downstream displacement of the PKA/PKC activity ratio to lower values,both in competing nerve terminals and at postsynaptic sites,plays a relevant role in controlling the elimination of supernumerary ***,calcium entry through L-and P/Q-subtypes of voltage-gated calcium channels(both channels are present,together with the n-type channel in developing nerve terminals)contributes to red

关键词： acetylcholine release adenosine receptors axonal competition brain-derived neurotrophic factor calcium channels motor end-plate muscarinic acetylcholine receptors postnatal synapse elimination serine kinases tropomyosin-related kinase receptorB

new design paradigm for heterogeneous catalysts

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national Science Review 2015年第2期2卷 140-143页

作者： aleksandra Vojvodic Jens K.n?rskov SUnCAT Center for Interface Science and Catalysis SLAC National Accelerator Laboratory Department of Chemical Engineering Stanford University

Both scientiic discovery and technological development are at some point faced with the question of how to progress from a trial-and-error approach to a highly controlled design *** heterogeneous catalysis,the search for the optimal active site of a catalyst for a given chemical reaction has been the central objective of research for almost a ***

关键词： new design paradigm for heterogeneous catalysts

Polyelectrolyte Complexes between Hyperbranched and Linear Polysaccharides: Fucoidan/Chitosan

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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

Development and characterization of 3D-printed electroconductive pHEMA-co-MAA nP-laden hydrogels for tissue engineering

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Bio-Design and Manufacturing 2024年第3期7卷 262-276页

作者： Sara De nitto aleksandra Serafin Alexandra Karadimou Achim Schmalenberger John J.EMulvihill Maurice n.Collins DIBRIS Polytechnic Inter-School Section University of Genoa16126 GenoaItaly School of Engineering Bernal InstituteUniversity of LimerickLimerick V94 T9PXIreland School of natural Sciences Department of Biological SciencesUniversity of LimerickLimerick V94 T9PXIreland Health Research Institute University of LimerickLimerick V94 T9PXIreland AMBER University of LimerickLimerick V94 T9PXIreland

Tissue engineering(TE)continues to be widely explored as a potential solution to meet critical clinical needs for diseased tissue replacement and tissue *** this study,we developed a poly(2-hydroxyethyl methacrylate-co-methacrylic acid)(pHEMA-co-MAA)based hydrogel loaded with newly synthesized conductive poly(3,4-ethylene-dioxythiophene)(PEDOT)and polypyrrole(PPy)nanoparticles(nPs),and subsequently processed these hydrogels into tissue engineered constructs via three-dimensional(3D)*** presence of the nPs was critical as they altered the rheological properties during ***,all samples exhibited suitable shear thinning properties,allowing for the development of an optimized processing window for 3D *** were 3D printed into pre-determined disk-shaped configurations of 2 and 10 mm in height and diameter,*** observed that the nPs disrupted the gel crosslinking efficiencies,leading to shorter degradation times and compressive mechanical properties ranging between 450 and 550 *** conductivity of the printed hydrogels increased along with the nP concentration to(5.10±0.37)×10^(−7)S/*** vitro studies with cortical astrocyte cell cultures demonstrated that exposure to the pHEMA-co-MAA nP hydrogels yielded high cellular viability and proliferation ***,hydrogel antimicrobial studies with staphylococcus epidermidis bacteria revealed that the developed hydrogels affected bacterial *** together,these materials show promise for various TE strategies.

关键词： Conductive nanoparticles Hydroxyethyl methacrylate(HEMA) Ultraviolet(UV)polymerization 3D printing

Improving nutrition for the prevention of gestational diabetes:Current status and perspectives

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World Journal of Diabetes 2021年第9期12卷 1494-1506页

作者： Polina V Popova Evgenii A Pustozerov aleksandra S Tkachuk Elena n Grineva Institute of Endocrinology Almazov National Medical Research CentreSaint Petersburg 194156Russia Department of Faculty Therapy Saint Petersburg Pavlov State Medical UniversitySaint Petersburg 197022Russia Department of Biomedical Engineering Saint Petersburg State Electrotechnical UniversitySaint Petersburg 197341Russia

Gestational diabetes mellitus(GDM)is a common complication of pregnancy and a serious public health *** carries significant risks of short-term and longterm adverse health effects for both mothers and their *** factors,especially modifiable risk factors,must be considered to prevent GDM and its *** studies have identified several nutritional and lifestyle factors associated with the risk of *** results of intervention studies examining the effects of diet and lifestyle on the prevention of GDM are *** in the study populations,types and intensity of intervention,time frame of the intervention,and diagnostic criteria for GDM may explain the heterogeneity in the results of intervention *** review provides an overview of new diets and other factors that may help prevent *** main results of epidemiological studies assessing the risk factors for GDM,as well as the results and methodological problems of intervention studies on the prevention of GDM and their meta-analyses,are *** addition,the evidence that gene and lifestyle interactions influence the development of GDM,as well as prospects for increasing the effectiveness of interventions designed to prevent GDM,including new data on the possible uses of personalized diet therapy,are highlighted.

关键词： Gestational diabetes mellitus Risk factors nutrition Prevention Personalized medicine Postprandial glycemic response

Impact of environmental factors on the sampling rate ofβ-blockers and sulfonamides from water by a carbon nanotube-passive sampler

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Journal of Environmental Sciences 2021年第3期33卷 413-427页

作者： Klaudia Godlewska aleksandra Jakubus Piotr Stepnowski Monika Paszkiewicz Department of Environmental Analysis Faculty of ChemistryUniversity of Gdanskul.Wita Stwosza 63Gdansk 80-308Poland

Passive techniques are a constantly evolving approach to the long-term monitoring of micropollutants,including pharmaceuticals,in the aquatic *** paper presents,for the first time,the calibration results of a new CnTs-PSDs(carbon nanotubes used as a sorbent in passive sampling devices)with an examination of the effect of donor phase salinity,water pH and the concentration of dissolved humic acids(DHAs),using both ultrapure and environmental *** rates(R_(s))were determined for the developed kinetic *** has been observed that the impact of the examined environmental factors on the R_(s) values strictly depends on the type of the *** the case ofβ-blockers,the only environmental parameter affecting their uptake rate was the salinity of water.A certain relationship was noted,namely the higher the salt concentration in water,the lower the Rs values ofβ-*** the case of sulfonamides,water salinity,water pH 7-9 and DHAs concentration decreased the uptake rate of these compounds by *** determined Rs values differed in particular when the values obtained from the experiments carried out using ultrapure water and environmental waters were *** general conclusion is that the calibration of novel CnTs-PSDs should be carried out under physicochemical conditions of the aquatic phase that are similar to the environmental matrix.

关键词： Carbon nanotubes Passive sampling Pharmaceuticals Sampling rates(R_s)

Initialisation of a hybrid AC/DC power system for harmonic stability analysis using a power flow formulation

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High Voltage 2020年第5期5卷 534-542页

作者： aleksandra Lekić Hakan Ergun Jef Beerten Department of Electrical Engineering(ESAT-ELECTA) KU LeuvenLeuvenBelgium

This study presents the initialisation of a hybrid alternating current/direct current(AC/DC)power system to determine the operation point around which the system is linearised as a starting point for an electromagnetic or harmonic stability *** this end,each AC or DC power system component is modelled in the Fourier transform domain and further adjusted to a simplified representation compatible with a power flow *** study also presents how voltage source converter(VSC)high-voltage DC-based systems can be analysed when the different VSC controls are *** result of the power flow solution is then used for the power converters’initialisation.

关键词： AC/DC system formulation

Dark energy constraints from joint analysis of standard rulers and standard candles

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Research in Astronomy and Astrophysics 2011年第6期11卷 641-654页

作者： Marek Biesiada Beata Malec aleksandra Piórkowska Department of Astrophysics and Cosmology Institute of PhysicsUniversity of Silesia Copernicus Center for Interdisciplinary Studies

We performed joint analysis of five cosmological models invoked to explain the accelerating expansion of the *** used the data from strong gravitational lensing systems,locations of cosmic microwave background acoustic peaks and baryon acoustic oscillation data in combination with supernova Ia data（Union2 compilation）.The observables we used came from both standard rulers and standard candles,so they had different parameter degeneracies and different restrictive powers in the parameter spaces of cosmological *** best fits we obtained for the model parameters in joint analysis turned out to prefer cases effectively equivalent to the ΛCDM *** were also in agreement with other combined studies performed by other authors on different sets of diagnostic *** theoretic methods used to assess which model is most supported by the data lead to the conclusion that the concordance model ΛCDM is clearly preferred in joint *** quintessence（both having constant or time varying equation of state） and Chaplygin gas get considerably less support from the data while the brane world（DGP） scenario is practically ruled out.

关键词： cosmology:observations-cosmological parameters-gravitational lensing-supernovae

Happy together？ Avoidance of conspecifics by gregarious mussels

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Current Zoology 2018年第1期64卷 53-61页

作者： Anna DZIERZYnSKA-BIALOnCZYK aleksandra SKRZYPCZAK Jaroslaw KOBAK Faculty of Biology and Environmental Protection Department of Invertebrate Zoology Nicolaus CopernicusUniversity Lwowska 1 Torun 87-100 Poland

Zebra mussel Dreissena polymorpha is a Ponto-Caspian species invasive in Europe and north America, with great environmental impact. It lives byssally attached to hard substrata in large aggregations, which is often explained by its preferences for conspecifics, though direct evidence for such preferences has been rather limited so far. We studied the reactions of zebra mussels to con- specifics, hypothesizing that they may either be attracted to one another or form aggregations only in the absence of alternative attachment sites, in Experiment 1, we tested mussel tendency to detach from existing druses depending on druse size （2-25 individuals） and substratum type （soft： sand; hard： glass）. Mussels detached significantly more often on the hard substratum and from larger druses compared to soft substratum and smaller druses, respectively. This indicates that mussels tended to avoid conspecifics at high density, particularly when alternative substratum was available. In Experiment 2, we tested the responses of single mussels to distant （3 or 15cm） conspecifics （0, 3, 15 individuals per 2.51 tank） on the sandy substratum. The presence of conspecifics, regardless of their distance and density, resulted in single unattached mussels staying more often in their initial positions. Mussels did not move preferentially towards or away from the conspecifics. Thus, even on unsuitable substratum mussels were not attracted by conspecifics and probably exhibited an avoidance reaction by reducing their movement. This suggests that dense mussel aggregations are formed due to the lack of available alternative attachment sites rather than due to their preferences for conspecifics.

关键词： active detachment Dreissena polymorpha movement mussel aggregations zebra mussel.