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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

High-contrast,fast chemical imaging by coherent Raman scattering using a self-synchronized two-colour fibre laser

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Light(Science & Applications) 2020年第1期9卷 1775-1786页

作者： Cihang Kong Christian Pilger Henning Hachmeister Xiaoming Wei tom H.Cheung Cora S.W.lai Nikki P.Lee Kevin K.Tsia Kenneth K.y.Wong Thomas Huser Department of Electrical and Electronic Engineering The University of Hong KongPokfulam RoadHong KongChina biomolecular Photonics Department of PhysicsUniversity of BielefeldUniversitatsstr2533615 BielefeldGermany Division of Life Science The Hong Kong University of Science and TechnologyHong KongChina Department of Physiology Li Ka Shing Faculty of MedicineThe University of Hong KongPokfulamHong KongChina Department of Surgery The University of Hong KongPokfulam RoadHong KongChina Division of Engineering and Applied Science California Institute of Technology1200 East California BoulevardPasadenaCA 91125USA

Coherent Raman scattering(CRS)microscopy is widely recognized as a powerful tool for tackling biomedical problems based on its chemically specific label-free contrast,high spatial and spectral resolution,and high ***,the clinical translation of CRS imaging technologies has long been hindered by traditional solid-state lasers with environmentally sensitive operations and large *** fibre lasers can potentially overcome these shortcomings but have not yet been fully exploited for CRS imaging,as previous implementations have suffered from high intensity noise,a narrow tuning range and low power,resulting in low image qualities and slow imaging ***,we present a novel high-power self-synchronized two-colour pulsed fibre laser that achieves excellent performance in terms of intensity stability(improved by 50 db),timing jitter(24.3 fs),average power fluctuation(20 db)and pulse width variation(ber range(2700-3550 cm^(−1)).The versatility of the laser source enables,for the first time,high-contrast,fast CRS imaging without complicated noise reduction via balanced detection *** capabilities are demonstrated in this work by imaging a wide range of species such as living human cells and mouse arterial tissues and performing multimodal nonlinear imaging of mouse tail,kidney and brain tissue sections by utilizing second-harmonic generation and twophoton excited fluorescence,which provides multiple optical contrast mechanisms simultaneously and maximizes the gathered information content for biological visualization and medical *** work also establishes a general scenario for remodelling existing lasers into synchronized two-colour lasers and thus promotes a wider popularization and application of CRS imaging technologies.

关键词： scattering tuning fibre

New radio observations of the Moon at L band

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Research in Astronomy and Astrophysics 2012年第9期12卷 1297-1312页

作者： Xi-Zhen Zhang Andrew Gray yan Su Jun-Duo Li tom Landecker Hong-bo Zhang Chun-lai Li National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China zxz @ nao. cas. cn Dominion Radio Astrophysical Observatory Penticton BC V2A 6K3 Canada

We present results of new radio observations of the Moon at L band with the synthesis telescope of the Dominion Radio Astrophysical Observatory Synthesis Telescope. The resolution and temperature sensitivity of the observations are 159 × 87 and 1.7K, respectively. The main results are: (1) the lunar brightness temperature averaged over the whole disk is about 233K while the average brightness temperature for the four quadrants are 228.1K (NE), 239.7K (NW), 233.9K (SW) and 228.8K (SE). The observations reveal large temperature and spatial variations on the Moon for the first time. The highest brightness temperature is about 257 K and it is located along the lunar equator, to the west. The total uncertainty is about 5% due to the absolute accuracy of the fluxes of the primary calibrators; (2) the total degree of po- larization is about 6%. both polarization intensity and degree of polarization increase from the disk’s center to the limb, and the distribution of the degree of polarization along the limb is not uniform; (3) the new data are used to study the properties of regolith, such as dielectric constant and thickness distribution. The results show that the lunar regolith’s thickness increases from the NW (mare area) to the SE (highland area) regions on the lunar surface.

关键词： techniques: high angular resolution-imaging processing — radio contin- uum: Moon

Antibiotic use in early childhood and risk of obesity: longitudinal analysis of a national cohort

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World Journal of Pediatrics 2019年第4期15卷 390-397页

作者： Dervla Kelly Alan Kelly tom O'Dowd Catherine b.Hayes Department of Public Health and Primary Care Trinity College DublinRussell CenterTallaght CrossDublin 24Ireland

background Taking oral antibiotics during childhood has been linked with an increased risk of childhood *** study assessed any potential association in number of courses of antibiotics taken between 2-3 and 4-5 years of age and body mass trajectory up to age *** The study was a secondary analysis of 8186 children and their parents from the infant cohort of the Irish National Longitudinal Study of *** use was measured by parental recall between ages 2-3 and *** models described the relationship between antibiotic exposure and body mass index (bMI) standard deviation scores andbinary outcomes,and examined interactions between covariates,which included socioeconomic status,diet assessed by food frequency questionnaires and maternal *** Any antibiotic usage between 2 and 3 years did not predict risk of overweight or obesity at age *** or more courses of antibiotics between 2 and 3 years were independently associated with obesity at age 5 (odds ratio 1.6,95% confidence interval 1.11-2.31).Effect size was modest (coefficient + 0.09 body mass SD units,standard error 0.04,P =0.037).Maternal bMI modified the relationship:≥ 4 courses of antibiotics between 2 and 3 years were associated with a + 0.12 body mass SD units increase in weight at age 5 among children of normal-weight mothers (P=0.035),but not in children of overweight *** Number of antibiotic courses,rather than antibiotic use,may be an important factor in any link between early antibiotic exposure and subsequent childhood *** is needed to confirm differential effects on babies of normal versus overweight/obese mothers independent of socioeconomic factors.

关键词： Antibiotics body mass index Early childhood Infants Obesity

Decomposition of labile and recalcitrant coniferous litter fractions affected by temperature during the growing season

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Journal of Forestry Research 2020年第4期31卷 1115-1121页

作者： Veronika Jílková Kristyna Dufková tomás Cajthaml Na Sádkách 7CeskéBudějovice 37005Czech Republic Faculty of Science Masaryk UniversityKotlárská267/2Brno 61137Czech Republic Institute for Environmental Studies Charles University in PragueBenátská2Prague 12801Czech Republic Institute of Microbiology Czech Academy of SciencesVídeňská1083Prague 14220Czech Republic

Temperate coniferous forest soils are considered important sinks of soil organic carbon(C).Fresh C inputs may,however,affect soil microbial activity,leading to increased organic matter decomposition and carbon dioxide *** consists of labile and recalcitrant fractions which are thought to be utilized by distinct microbial communities and at different rates during the growing *** this study,we incubated the whole litter(LC+RC),the labile(LC)and the recalcitrant(RC)fractions with the coniferous soil at two temperatures representing spring/autumn(10℃)and summer(20℃)for one *** respiration and microbial community composition were regularly determined using phospholipid fatty acids as *** LC fraction greatly increased soil respiration at the beginning of the incubation period but this effect was rather *** effect of the RC fraction persisted longer and,together with the LC+RC fraction,respiration increased during the whole incubation *** of the RC fraction was more strongly affected by higher temperatures than decomposition of the more labile fractions(LC and LC+RC).However,when we consider the relative increase in soil respiration compared to the dH2 O treatment,respiration increased more at a lower temperature,suggesting that available C is more important for microbial metabolism at lower *** C was added only once in our study,no changes in microbial community composition were detected,possibly because the microbial community is adapted to relatively low amounts of additional C such as the amounts naturally found in litter.

关键词： Temperate forest Picea abies Soil respiration Hot water-extractable carbon PLFA (phospholipid fatty acids)

Analytical and technological aspects of amylose inclusion complexes for potential applications in functional foods

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Food bioscience 2022年第3期47卷 17-31页

作者： Andrea E.Di Marco Vanesa y.Ixtaina Mabel C.tomás Centro de Investigación y Desarrollo en Criotecnología de Alimentos CIDCA CCT La Plata CONICETFacultad de Ciencias Exactas FCE-UNLPCICPBAcalle 47 y 1161900La PlataArgentina Facultad de Ciencias Agrarias y Forestales FCAyF-UNLP calle 60 y 1191900La PlataArgentina

The linear component of starch,amylose,has the ability to interact with hydrophobic molecules forming inclusion complexes(ICs).These structures have gained a particular interest for potential food applications,either as dietary fiber or as delivery systems of bioactive *** the second case,the complexation of sensitive molecules is directed to protect them from processing,storage and stomach conditions and to guarantee a sustained release in the gastrointestinal *** present review covers the analytical and technological aspects of inclusion complexes,with focus on their potential application in the development of functional *** was addressed by first explaining the methodologies used for the analytical assessment of their structural,thermal,and functional properties,followed by the study of the functionality of ICs as carrier agents of different bioactive compounds and food ingredients,including alpha-lipoic acid,α-linolenic and linoleic fatty acids,conjugated linoleic acid,ascorbyl palmitate,phenolic compounds,and *** also covers the application of ICs in food products and the analysis of the potential industrial scalability of the formation *** analytical methodologies allowed a complete characterization of the *** structures have shown suitable functional properties as delivery systems of the bioactive compounds and flavors covered in this *** incorporation of ICs in food has led to the development of products with improved nutritional and/or functional *** successful formation of complexes using methods suitable for an industrial scale represents promising preliminary results to achieve the scalability of the ICs production in the near future.

关键词： Amylose inclusion complex Delivery system bioactive compound V-type structure

Software for automated classification of probe-based confocal laser endomicroscopy videos of colorectal polyps

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World Journal of Gastroenterology 2012年第39期18卷 5560-5569页

作者： barbara André tom Vercauteren Anna M buchner Murli Krishna Nicholas Ayache Michael b Wallace Image Computing Group Mauna Kea Technologies75010 ParisFrance Asclepios Research Team The National Institute for Research in Computer Science and Control Sophia Antipolis06902 Sophia AntipolisFrance Division of Gastroenterology Hospital of theUniversity of PennsylvaniaPhiladelphiaPA 19104United States Laboratory Medicine and Pathology Mayo Clinic Hospital in JacksonvilleJacksonvilleFL 3224United States Department of Gastroenterology and Hepatology Mayo Clinic Hospital in JacksonvilleJacksonvilleFL 3224United States

AIM:To support probe-based confocal laser endomi-croscopy (pCLE) diagnosis by designing software for the automated classification of colonic polyps. METHODS:Intravenous fluorescein pCLE imaging of colorectal lesions was performed on patients under-going screening and surveillance colonoscopies, followed by polypectomies. All resected specimens were reviewed by a reference gastrointestinal pathologist blinded to pCLE information. Histopathology was used as the criterion standard for the differentiation between neoplastic and non-neoplastic lesions. The pCLE video sequences, recorded for each polyp, were analyzed off-line by 2 expert endoscopists who were blinded to the endoscopic characteristics and histopathology. These pCLE videos, along with their histopathology diagnosis, were used to train the automated classification software which is a content-based image retrieval technique followed by k-nearest neighbor classification. The performance of the off-line diagnosis of pCLE videos established by the 2 expert endoscopists was compared with that of automated pCLE software classification. All evaluations were performed using leave-one-patient- out cross-validation to avoid bias. RESULTS:Colorectal lesions (135) were imaged in 71 patients. based on histopathology, 93 of these 135 lesions were neoplastic and 42 were non-neoplastic. The study found no statistical significance for the difference between the performance of automated pCLE software classification (accuracy 89.6%, sensitivity 92.5%, specificity 83.3%, using leave-one-patient-out cross-validation) and the performance of the off-line diagnosis of pCLE videos established by the 2 expert endoscopists (accuracy 89.6%, sensitivity 91.4%, specificity 85.7%). There was very low power (bserved differences. The 95% confidence intervals for equivalence testing were:-0.073 to 0.073 for accuracy, -0.068 to 0.089 for sensitivity and -0.18 to 0.13 for specificity. The classification software proposed i

关键词： Colorectal neoplasia Computer-aided diag-nosis Content-based image retrieval Nearest neigh-bor classification software Probe-based confocal laserendomicroscopy

A Proposal for the Automatic Computation of Envelopes of Families of Plane Curves

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Journal of Systems Science & Complexity 2019年第1期32卷 150-157页

作者： bOTANA Francisco RECIO tomás Depto. de Matemática Aplicada I Universidad de Vigo Campus A Xunqueira Depto. de Matemáticas Estad'?stica y Computación Universidad de Cantabria

The idea of envelope of a family of plane curves is an elementary notion in differential geometry. As such, its implementation in dynamic geometry environments is quite universal(Cabri,The Geometer's Sketchpad, Cinderella, Geo Gebra,...). Nevertheless, most of these programs return,when computing certain envelopes, both some spurious solutions and the curves that truly ?t in the intuitive de?nition of envelope. The precise distinction between spurious and genuine parts has not been made before: This paper proposes such distinction in an algorithmic way, ready for its implementation in interactive geometry systems, allowing a ?ner classi?cation of the different parts resulting from the current, advanced approach to envelope computation and, thus, yielding a more precise output, free from extraneous components.

关键词： Automated deduction in geometry dynamic geometry envelopes parametric polynomial systems symbolic computation

The molecular profile of nerve repair: humans mirror rodents

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Neural Regeneration Research 2021年第7期16卷 1440-1441页

作者： Matthew b.Wilcox Kristjan R.Jessen tom J.Quick James b.Phillips Peripheral Nerve Injury Research Unit Royal National Orthopaedic HospitalStanmoreUK Department of Pharmacology UCL School of PharmacyUniversity College LondonLondon WC1N 1AXUK UCL Centre for Nerve Engineering University College LondonLondonUK Department of Cell and Developmental biology University College LondonLondonUK

Peripheral nerve injuries(PNI)are common following blunt or penetrating trauma and can lead to disability and chronic pain in affected individuals,with limited options available to promote regeneration and functional *** animal models,it is known that the regenerative capacity of the peripheral nervous system(PNS)is heavily dependent upon the remarkable ability of Schwann cells to undergo a phenotypic shift from a supportive/myelinating/maintaining phenotype to one that encourages neural regeneration.

关键词： injuries mirror neural