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A method to determine relevant geomechanical parameters for evaluating the hydraulic erodibility of rock

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第5期11卷 1004-1018页

作者： Lamine Boumaiza Ali Saeidi marco Quirion Département des Sciences appliquées Universitédu QuébecàChicoutimiChicoutimiG7H 2B1Canada Expertise en barrages Direction Barrages et infrastructuresHydro-QuébecMontréalH2Z 1A4Canada

Among the methods used for evaluating the potential hydraulic erodibility of rock,the most common methods are those based on the correlation between the force of flowing water and the capacity of a rock to resist erosion,such as Annandale’s and Pells’*** capacity of a rock to resist erosion is evaluated based on erodibility indices that are determined from specific geomechanical parameters of a rock *** indices include unconfined compressive strength(UCS)of rock,rock block size,joint shear strength,a block’s shape and orientation relative to the direction of flow,joint openings,and the nature of the surface to be potentially ***,it is difficult to determine the relevant geomechanical parameters for evaluating the hydraulic erodibility of *** assessment of eroded unlined spillways of dams has shown that the capacity of a rock to resist erosion is not accurately *** more than 100 case studies,we develop a method to determine the relevant geomechanical parameters for evaluating the hydraulic erodibility of rock in unlined *** UCS of rock is found not to be a relevant parameter for evaluating the hydraulic erodibility of *** the other hand,we find that the use of three-dimensional(3D)block volume measurements,instead of the block size factor used in Annandale’s method,improves the rock block size ***,the parameter representing the effect of a rock block’s shape and orientation relative to the direction of flow,as considered in Pells’method,is more accurate than the parameter adopted by Annandale’s method.

关键词： Rock mass Hydraulic erodibility Geomechanical parameters Rock block size Annandale’s method Pells’method Kirsten’s index Erosion level

Quantum simulations of materials on near-term quantum computers

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npj Computational Materials 2020年第1期6卷 947-954页

作者： He Ma marco Govoni Giulia Galli Department of Chemistry University of ChicagoChicagoIL 60637USA Materials Science Division and Center for Molecular Engineering Argonne National LaboratoryLemontIL 60439USA Pritzker School of Molecular Engineering University of ChicagoChicagoIL 60637USA

Quantum computers hold promise to enable efficient simulations of the properties of molecules and materials;however,at present they only permit ab initio calculations of a few atoms,due to a limited number of *** order to harness the power of near-term quantum computers for simulations of larger systems,it is desirable to develop hybrid quantum-classical methods where the quantum computation is restricted to a small portion of the *** is of particular relevance for molecules and solids where an active region requires a higher level of theoretical accuracy than its ***,we present a quantum embedding theory for the calculation of strongly-correlated electronic states of active regions,with the rest of the system described within density functional *** demonstrate the accuracy and effectiveness of the approach by investigating several defect quantum bits in semiconductors that are of great interest for quantum information *** perform calculations on quantum computers and show that they yield results in agreement with those obtained with exact diagonalization on classical architectures,paving the way to simulations of realistic materials on near-term quantum computers.

关键词： theory quantum exact

Inhibition of tubulin detyrosination:a novel strategy to promote central nervous system regeneration

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Neural Regeneration Research 2024年第12期19卷 2557-2558页

作者： Charlotte Zeitler marco Leibinger Dietmar Fischer Center of Pharmacology Institute for PharmacologyMedical Faculty and University of CologneCologneGermany

The adult mammalian central nervous system(CNS) coordinates essential functions such as sensation,movement,autonomic control,thought processes,and ***,injuries or diseases of the CNS are often associated with devastating and permanent functional impairments because damaged axons normally fail to *** insufficient neuron-intrinsic growth capacity and an inhibitory environment at the injury site are the leading causes of this regenerative failure.

关键词： injuries sensation diseases

Retinoprotective compounds,current efficacy,and future prospective

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Neural Regeneration Research 2023年第12期18卷 2619-2622页

作者： Rachele Marino Rebecca Sappington marco Feligioni Laboratory of Neuronal Cell Signaling EBRI Rita Levi-Montalcini FoundationRomeItaly Department of Neurobiology and Anatomy Wake Forest School of MedicineAtrium Health Wake Forest Baptist Medical CenterWinston-SalemNCUSA Department of Ophthalmology Wake Forest School of MedicineWinston-SalemNCUSA Department of Neurorehabilitation Sciences Casa di Cura IgeaMilanItaly

Retinal dysfunction is the most common cause of vision loss in several retinal *** has been estimated a great increase in these pathologies that are becoming more globally widespread and numerous over time,also supported by the life expectancy *** different types of retinopathies,we can account some that share causes,symptoms,and treatment including diabetic retinopathy,age-related macular degeneration,glaucoma,and retinitis *** changes,environmental factors,and genetic predisposition might be some of the main causes that drive retinal tissue to chronic inflammation and neurodegeneration in these *** treatments available on the market contain compounds that efficiently ameliorate some of the important clinical features of these pathologies like stabilization of the intraocular pressure,reduction of eye inflammation,control of eye oxidative stress which are considered the major molecular mechanisms related to retinal ***,the most commonly used drugs are antiinflammatories,such as corticosteroids,antioxidant,hypotonic molecules and natural neuroprotective ***,these drugs,which are fundamental to treating disease symptoms,are not capable to cure the pathologies and so they are not life-changing for *** review provided an overview of current treatments on the market,but more interestingly,wants to be a quick window on the new treatments that are now in clinical ***,it has been here highlighted that the recent technical enhancement of the investigation methods to identify the various retinopathies causes might be used as a sort of“precise medicine”approach to tailor the identification of molecular pathways involved and potentially study a dedicated treatment for each *** approach includes the use of cutting-edge technologies like gene therapy and metabolomics.

关键词： age-related macular degeneration anti-inflammatory drugs antioxidants diabetic retinopathy glaucoma neuroprotective compounds retinitis pigmentosa retinopathies vision loss

Mitochondrial selfish elements and the evolution of biological novelties

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Current Zoology 2016年第6期62卷 687-697页

作者： Liliana MILANI Fabrizio GHISELLI marco PASSAMONTI Department of Biological Geological and Environmental Sciences University of Bologna Via Selmi 3 40126Bologna Italy

We report the present knowledge about RPHM21, a novel male-specific mitochondrial protein with a putative role in the paternal inheritance of sperm mitochondria in the Manila clam Ruditapes philippinarum, a species with doubly uniparental inheritance of mitochondria （DUI）. We review all the available data on rphm21 transcription and translation, analyze in detail its female counterpart, RPHF22, discuss the homology with RPHM21, the putative function and origin, and analyze their polymorphism. The available evidence is compatible with a viral origin of RPHM21 and supports its activity during spermatogenesis. RPHM21 is progressively accumulated in mitochondria and nuclei of spermatogenic cells, and we hypothesize it can influence mitochondrial inheritance and sex- ual differentiation. We propose a testable model that describes how the acquisition of selfish fea- tures by a mitochondrial lineage might have been responsible for the emergence of DUI, and for the evolution of separate sexes （gonochorism） from hermaphroditism. The appearance of DUI most likely entailed the invasion of at least 1 selfish element, and the extant DUI systems can be seen as resolved conflicts. It was proposed that hermaphroditism was the ancestral condition of bivalves, and a correlation between DUI and gonochorism was documented. We hypothesize that DUI might have driven the shift from hermaphroditism to gonochorism, with androdioecy as transi- tion state. The invasion of sex-ratio distorters and the evolution of suppressors can prompt rapid changes among sex-determination mechanisms, and DUI might have been responsible for one of such changes in some bivalve species. If true, DUI would represent the first animal sex-determination system involving mtDNA-encoded proteins.

关键词： bivalve mollusc doubly uniparental inheritance (DUI) endogenized virus germ line gonochorism hermaphroditism

Sex-specifc seasonal variations of wild boar distance traveled and home range size

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Current Zoology 2024年第3期70卷 284-290页

作者： Silvia Cavazza Rudy Brogi marco Apollonio Department of Veterinary Medicine University of Sassarivia Vienna 2I-07100 SassariItaly

Distance traveled and home range size describe how animals move in *** seasonal variations of these parameters are important to comprehensively understand animal ecology and its connection with reproductive behavior and energy *** usually estimate the distance traveled as the sum of the straight-line displacements between sampled positions,but this approach is sensitive to the sampling frequency and does not account for the tortuosity of the animal’s *** means of the continuous-time movement modeling which takes into account autocorrelation and tortuosity of movement data,we estimated the distance traveled and monthly home range size of 28 wild boar Sus scrofa and modeled their inter-sexual seasonal *** traveled longer distances and used larger home ranges than females,particularly during the rut in autumn-winter,consistently with the different biological cycles of males and *** enlarged their home ranges during the rut but traveled constant average distances along the year,whereas females traveled shorter distances in correspondence with the peak of food resources and birth periods but exhibited constant home range size across *** differences between the seasonal variation patterns of distance traveled and home range size,observed in both sexes,revealed the complex relationship between these two aspects of spatial behavior and the great opportunity of including both distance traveled and home range size in behavioral ecology *** provided a detailed analysis of wild boar spatial behavior and its relationships with the reproductive cycles of males and females,promoting a deeper comprehension of their behavioral ecology.

关键词： continuous-time ctmm daily range movements spatial behavior Sus scrofa

Spatial separation effects in a guiding procedure in a modified ion-beam-sputtering process

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Light(Science & Applications) 2015年第1期4卷 109-116页

作者： Sina Malobabic marco Jupé Detlev Ristau Laser Zentrum Hannover e.V. Hollerithallee 8D-30419 HannoverGermany QUEST:Centre for Quantum Engineering and Space-Time Research Leibniz Universität HannoverHannoverGermany

In the present state of the art,ion beam sputtering is used to produce low-loss dielectric *** the manufacturing of a dielectric layer stack,the deposition material must be changed,which requires rapid mechanical movement of vacuum *** mechanical components can be regarded as a risk factor for contamination during the coating process,which limits the quality of high-end laser *** minimize the particle contamination,we present a novel deposition concept that does not require movable components to change the coating material during the coating process.A magnetic field guiding technique has been developed,which enables the tuning of the refractive index in the layer structure by sputtering mixtures with varying compositions of two materials using a single-ion *** versatility of this new concept is demonstrated for a highreflection mirror.

关键词： EM field separation ion beam sputtering plasma guiding

Vegetation cover induces developmental plasticity of lateralization in tadpoles

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Current Zoology 2020年第4期66卷 393-399页

作者： Tyrone Lucon-Xiccato marco Dadda Angelo Bisazza department of Life Sciences and Biotechnology University of FerraraVia L.Borsari 4644121FerraraItaly Department of General Psychology University of PadovaVia Venezia 83511PadovaItaly

Lateralization of cognitive functions influences a large number of fitness-related behaviors and shows,in most species,substantial variation in strength and *** works and field data have suggested that this variation is often due to adaptive phenotypic *** lateralization should be favored in some ecological conditions,for example,under high risk of *** anuran tadpoles,the presence of cover affects predation risk,with tadpoles being more exposed to predators in environments with reduced *** tested the hypothesis that the amount of cover experienced early in life affects lateralization in the edible frog,Pelophylax escu-lentus,*** exposed embryos and larvae to high or low vegetation cover *** half of the subjects,the treatment was constant whereas the remaining subjects were switched to the opposite treatment after *** agreement with the theoretical expectation,tadpoles exposed to low vegetation cover for the entire development were more lateralized and showed a stronger alignment in directionality of lateralization compared with tadpoles exposed to high vege-tation *** indicates a possible role of natural variation in vegetation abundance and deve卜opmental plasticity as determinants of between-population and between-individual differences in *** also found that shifting from high to low vegetation cover treatments and vice versa disrupted lateralization alignment,suggesting that developmental trajectories for this trait are determined at the embryonic stage and need environmental stability to be fully expressed.

关键词： lateralization light exposure Pelophylax esculentus phenotypic plasticity

Highlights of ASS234: a novel and promising therapeutic agent for Alzheimer’s disease therapy

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Neural Regeneration Research 2020年第1期15卷 30-35页

作者： Alejandro Romero Josémarco-Contelles Eva Ramos Department of Pharmacology&Toxicology Faculty of Veterinary MedicineComplutense University of MadridMadridSpain Laboratory of Medicinal Chemistry Institute of General Organic Chemistry(CSIC)MadridSpain

There is no effective treatment to face Alzheimer’s disease *** molecules are a good approach against the multiple physiopathological events associated with its development and *** this context,N-((5-(3-(1-benzylpiperidin-4-yl)propoxy)-1-methyl-1H-indol-2-yl)methyl)-N-methylprop-2-yn-1-amine(ASS234)has been tested achieving promising ***234 has demonstrated to cross the blood-brain barrier in vivo,and a good in silico safety profile being less toxic than ***,ASS234 reversibly inhibits human acetyl-and butyryl-cholinesterase,and irreversibly inhibits human monoamine oxidase A and ***,this multitarget molecule has antioxidant and neuroprotective properties,and inhibitsΑβ1–42 andΑβ1–40 *** about the mechanism of action,several signaling pathways related to Alzheimer’s disease had been explored showing that ASS234 induces the wingless-type MMTV integration site(Wnt)family and several members of the heat shock proteins family and moreover counteracts neuroinflammatory and oxidative stress-related genes promoting the induction of several key antioxidant ***,in vivo experiments with ASS234 in C57BL/6J mice displayed its ability to reduce amyloid plaque burden and gliosis in the cortex and hippocampus,ameliorating scopolamine-induced learning *** we gather the information regarding ASS234 evaluated so far,showing its ability to face different targets,necessary to counteract a neurodegenerative disease as complex as the Alzheimer’s disease.

关键词： AChE BuChE gene expression heat shock proteins inflammation in silico toxicology MAO A/B neuroprotection oxidative stress Wnt signaling