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DZ Lyn:a contact binary with components in poor thermal contact

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Research in Astronomy and Astrophysics 2009年第11期9卷 1270-1276页

作者： Massimiliano Martignoni Francesco Acerbi Carlo Barani via Don G. Minzoni 26/D 20020 Magnago(MI)Italy via Zoncada 51 26845 Codogno(LO)Italy via molinetto 35 26845 Triulza di Codogno(LO)Italy

CCD photometric observations of the short-period eclipsing binary DZ Lyn were obtained during seven nights in March-April 2008 in the B, V, Rc and Ic bands; these observations confirm the short-period （P = 0.378 d） of the system. The presented light curves are analyzed by means of the 2003 version of the Wilson-Devinney （WD） program. A grid of solutions for several fixed values of mass ratio was calculated. The best fitting possible is for a mass ratio of q -- 0.885, a degree of contact f = 0.18 and a low orbital inclination of i = 57.6°. The results show that DZ Lyn is an A-subtype W Ursae Majoris contact binary in poor thermal contact; in fact the difference between the mean temperatures of the components is about 1800 K. The star DZ Lyn seems to be another member of the class of poorly understood close binaries in or near geometrical contact but far from thermal contact. The absolute dimensions are estimated and its dynamical evolution is inferred.

关键词： binaries eclipsing -- stars fundamental parameters -- stars individual DZ Lyn

Photometric study and preliminary elements of the low-mass ratio W UMa system ASAS 021209+2708.3

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Research in Astronomy and Astrophysics 2011年第7期11卷 843-850页

作者： Francesco Acerbi Carlo Barani Massimiliano Martignoni via Zoncada 51 26845 Codogno(LO)Italy via molinetto 35 26845 Triulza di Codogno(LO)Italy via Don G.Minzoni 26/D 20020 Magnago(MI)Italy

We present CCD B and V light curves,obtained in the year 2006,and a photometric solution of the low-mass ratio contact binary ASAS 021209＋2708.3. With our data we were able to determine six new times of minimum light and refine the orbital period of the system to 0.3181963 *** light curves are analyzed using the 2003 version of the Wilson-Devinney program and the analysis was performed with and without adding a spot on the surface of one star because the light curves appear to exhibit a typical O’Connell effect,with Maximum I brighter than Maximum *** results show that ASAS 021209＋2708.3 may be classified as an A-subtype W Ursae Majoris system with a small mass ratio q=0.1889,a large over-contact degree of f= 0.587,a very small difference between the component temperatures of Δ T=53 K and an orbital inclination of i=81°.It is known that deep（f50%） ,low-mass ratio（q0.25） overcontact binary stars are a very important resource for understanding the phenomena of Blue Straggler/FK Com-type *** formations of Blue Straggler stars and FK Com-type stars are unsolved problems in stellar *** of the possible explanations for their formation is from the coalescence of W UMa-type overcontact binary *** absolute dimensions of ASAS 021209＋2708.3 are estimated and its dynamical evolution is inferred.

关键词： binaries:eclipsing–stars:fundamental parameters–stars:individual:ASAS 021209+2708.3

Absolute parameters of the three totally-eclipsing W UMa stars NSVS 2443858,NSVS 780649 and V1098 Her

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Research in Astronomy and Astrophysics 2021年第9期21卷 124-134页

作者： Velimir Popov Francesco Acerbi Carlo Barani Department of Physics and Astronomy Shumen University115 Universitetska str.9700 ShumenBulgaria via Zoncada 51 26845 Codogno(LO)Italy via molinetto 35 26845 Triulza di Codogno(LO)Italy

We present the first photometric analysis of three totally-eclipsing W UMa binaries,NS VS2443858,NSVS 780649 and V1098 *** absolute astrophysical parameters of the stellar components were determined by means of Gaia distances and light curve *** results show that:(ⅰ)Two of the systems,NSVS 2443858 and V1098 Her,are of A subtype while the obtained temperature of the secondary component of NSVS 780649 indicates that it is a W-subtype system;(ⅱ)The estimated mass ratios approach the lower limit of the mass ratio assumed by researchers in recent years so our targets could be classified as extreme mass ratio binary(EMRB)systems;(ⅲ)All the systems have deep contact configurations,so they also are deep low mass ratio(DLMR)systems;(ⅳ)The components of our systems are stars of F and G spectral type and undergo total eclipses;(ⅴ)The sum 0.871 M⊙of the component masses of NSVS 780649 is below the mass limit of 1.0-1.2 M⊙assumed for the known contact binary stars.

关键词： techinques:photometric binaries:eclipsing stars:fundamental parameters stars:individual

How dopamine tunes parvalbumin interneurons in the hippocampus:new experimental observations in Alzheimer's disease

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Neural Regeneration Research 2025年第5期20卷 1405-1406页

作者： Livia La Barbera Paraskevi Krashia Annalisa Nobili Department of Medicine and Surgery UniversitàCampus Bio-Medico di RomaViaÁlvaro del PortilloRomeItaly Department of Experimental Neurosciences IRCCS Santa Lucia FoundationVia del Fosso di FioranoRomeItaly Department of Science and Technology for Sustainable Development and One Health UniversitàCampus Bio-Medico di RomaViaÁlvaro del PortilloRomeItaly

Despite decades of dedicated resea rch,Alzheimer's disease (AD) is an age-related and progressive neurodegenerative disorder for which the mechanisms of onset are sti unc *** is cha racterized by featured histological alterations including amyloid-beta (AB) plaque deposition,accumulation of neurofibrillary to ngles of hyperphosphorylated-tau,and neuronal loss,accompanied by progressive cognitive decline and behavioral changes.

关键词： Alzheimer alterations dopamine

Influence of uncertainties: A focus on block volume and shape assessment for rockfall analysis

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第9期15卷 2250-2263页

作者： Gessica Umili Battista Taboni Anna Maria Ferrero Department of Earth Sciences University of Turinvia Valperga Caluso 3510125TurinItaly

Block size and shape depend on the state of fracturing of the rock mass and,consequently,on the geometrical features of the discontinuity sets(mainly orientation,spacing,and persistence).The development of non-contact surveying techniques applied to rock mass characterization offers significant advantages in terms of data numerosity,precision,and accuracy,allowing for performing a rigorous statistical analysis of the *** fact is particularly evident when dealing with rockfall phenomena:uncertainties in spacing and orientation data could significantly amplify the uncertainties connected with in situ block size distribution(IBSD),which represents a relation between each possible value of the volume and its probability of not being *** addition to volume,block shape can be considered as a derived parameter that suffers from *** attempts to model the possible trajectories of blocks considering their actual shape have been proposed,aiming to reproduce the effect on *** authors proposed analytical equations for calculating the expected value and variance of volume distributions,based on the geometrically correct equation for block volume in the case of three discontinuity *** quantify and discuss the effect of both volume and shape variability through a synthetic case ***,a fictitious rock mass with three discontinuity sets is assumed as the source of *** IBSDs obtained considering different spacing datasets are quantitatively compared,and the overall uncertainty effect is assessed,proving the correctness of the proposed ***,block shape distributions are obtained and compared,confirming the variability of shapes within the same ***,a comparison between trajectory simulations on the synthetic slope is reported,aiming to highlight the effects of the propagation of uncertainties to block volume and shape *** benefits of an approach that can quantify the uncertainties are discussed

关键词： Rockfall In situ block size distribution(IBSD) Block Volume Shape Uncertainty

EPOXYDON─LIKE ANTIBIOTICS

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中国抗生素杂志 1986年第6期11卷 474-484页

作者： G.P.Orezzi,E.Arlandini,M.Ballabio,G.Cassinelli,E.DiMatteo,M.L.Garofano,A.Inventi-Solari,E.Arcamone Farmitalia Carlo Erba SpA Research Labs Farmitalia Carlo Erba SpA Research Labs Farmitalia Carlo Erba SpA Research Labs Farmitalia Carlo Erba SpA Research Labs Farmitalia Carlo Erba SpA Research Labs Farmitalia Carlo Erba SpA Research Labs Farmitalia Carlo Erba SpA Research Labs Farmitalia Carlo Erba SpA Research Labs 20146 Milan via dei Gracchi 35 Italy 20146 Milan via dei Gracchi 35 Italy 20146 Milan via dei Gracchi 35 Italy 20146 Milan via dei Gracchi 35 Italy 20146 Milan via dei Gracchi 35 Italy 20146 Milan via dei Gracchi 35 Italy 20146 Milan via dei Gracchi 35 Italy 20146 Milan via dei Gracchi 35 Italy

SUMMARY A treptomyces species,designed No.2061 FCE,was found to produce twoantibacterial antibiotics belonging to the epoxidon group, Structural studiesdemonstrated the identity of the less polar active constituent 2061-A(Ⅰ)with an-tibiotic G-7063-2 and the novelty of the most polar one 2061-B(Ⅱ),whosestructure correspondes to that of 5-dihydroderivative of Ⅰ.2061-A and 2061-Bdisplay respectively a moderate and weak activity against gram-positive and gramnegative bacteria“in vitro”.Chemical,physico-chemical and some biological proper-ties of compounds belonging to the epoxidon group are also reviewed.

关键词： Figure LIKE ANTIBIOTICS EPOXYDON

Nucleo-cytoplasmic transport defects and protein aggregates in neurodegeneration

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Translational Neurodegeneration 2020年第3期9卷 354-369页

作者： Giacomo Bitetto Alessio Di Fonzo IRCCS Foundation Ca'Granda Ospedale Maggiore Policlinico Dino Ferrari CenterNeuroscience SectionDepartment of Pathophysiology and TransplantationUniversity of MilanVia Francesco Sforza 3520122 MilanItaly

In the ongoing process of uncovering molecular abnormalities in neurodegenerative diseases characterized by toxic protein aggregates,nucleo-cytoplasmic transport defects have an emerging *** pieces of evidence suggest a link between neuronal protein inclusions and nuclear pore complex(NPC)*** processes lead to oxidative stress,inefficient transcription,and aberrant DNAVRNA *** clinical and neuropathological spectrum of NPC defects is broad,ranging from physiological aging to a suite of neurodegenerative diseases.A better understanding of the shared pathways among these conditions may represent a significant step toward dissecting their underlying molecular mechanisms,opening the way to a real possibility of identifying common therapeutic targets.

关键词： Aging Neurodegeneration Neurodegenerative disease Nucleo-cytoplasmic transport Nuclear pore complex Protein aggregate

A randomized trial of iron depletion in patients with nonalcoholic fatty liver disease and hyperferritinemia

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World Journal of Gastroenterology 2014年第11期20卷 3002-3010页

作者： Luca Valenti Anna Ludovica Fracanzani Paola Dongiovanni Serena Rovida Raffaela Rametta Erika Fatta Edoardo Alessandro Pulixi Marco Maggioni Silvia Fargion Department of Pathophysiology and Transplantation Metabolic Liver Diseases Research CenterUniversità degli Studi di MilanoFondazione IRCCS Ca' Granda Ospedale Policlinicovia F Sforza 3520122MilanoItaly

AIM: To compare iron depletion to lifestyle changes alone in patients with severe nonalcoholic fatty liver disease (NAFLD) and hyperferritinemia, a frequent feature associated with more severe liver damage, despite at... 详细信息

关键词： Nonalcoholic fatty liver disease Iron depletion Randomized controlled trial Ferritin

Syndecans in Alzheimer's disease:pathogenetic mechanisms and potential therapeutic targets

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Neural Regeneration Research 2025年第9期20卷 2594-2595页

作者： Carmela Rita Balistreri Roberto Monastero Cellular Molecular and Clinical Pathological LaboratoryDepartment of BiomedicineNeuroscience and Advanced Diagnostics(Bi.N.D.)University of PalermoPalermoItaly Memory and Parkinson’s disease Center Policlinico“Paolo Giaccone”PalermoDepartment of BiomedicineNeuroscience and Advanced Diagnostics(Bi.N.D.)University of PalermoVia La Loggia 1PalermoItaly

With increasing age,humans become more susceptible to the onset of neurodegenerative diseases(NDs),and among these,Alzheimer's disease(AD)is the most frequent(Nicoletti et al.,2023).NDs are primarily characterized by neuronal loss and atrophy,but also by lesions involving the cerebral and/or cardiovascular system(Balistreri,2021).Lesions such as macroinfa rcts,microinfarcts,hemorrhages,white matter lesions,atherosclerosis,and arteriolosclerosis have also been significantly described in the preclinical stages of cognitive impairment characterizing NDs(Mariani et al.,2007).

关键词： Alzheimer cardiovascular