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Particuology 2023年第7期78卷 122-135页

作者： Wojciech Sadowski francesca di Mare Chair of Thermal Turbomachines and Aeroengines Department of Mechanical EngineeringRuhr University BochumUniversitatsstr.15044801Germany

The porous-fluid interface encompasses a region bridging the flow inside a porous medium and a free-flowing *** the context of volume-averaged simulations,it can be described by a set of gradually changing parameters defining the porous medium,mainly porosity and *** this paper,both the permeability and the porous-induced drag force are evaluated a-priori,by explicitly filtering a set of Particle-Resolved Simulations(PRS)of the flow in the channel partially occupied by the porous *** porous matrices are considered and the influence of the geometry and filtering parameters on the macroscopic quantities is ***,the focus is placed on the requirements for the kernel type and size to perform filtering accurately,and their impact on the distribution of permeability at the *** performance of the typically used models for the permeability is compared to the explicitly filtered ***,a new model for permeability and the drag force is introduced,taking into account the information about the fltering size and non-uniformity of the velocity *** model greatly improves the prediction of velocity at the porous-fluid interface and serves as a proof of concept that a successful porous drag model should strive to include information about both parameters.

关键词： Porous-fluid interface Explicit filtering Permeability Porous drag

Simulation of unconventional well tests with the finite volume method

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Petroleum Science 2012年第3期9卷 317-329页

作者： CANCELLIERE Michel VERGA francesca Politecnico di Torino DITAGTorino (TO) 10129 Italy

The finite volume method has been successfully applied in several engineering fields and has shown outstanding performance in fluid dynamics simulation. In this paper, the general framework for the simulation ofnear-wellbore systems using the finite volume method is described. The mathematical model and the numerical model developed by the authors are presented and discussed. A radial geometry in the vertical plane was implemented so as to thoroughly describe near-wellbore phenomena. The model was then used to simulate injection tests in an oil reservoir through a horizontal well and proved very powerful to correctly reproduce the transient pressure behavior. The reason for this is the robustness of the method, which is independent of the gridding options because the discretization is performed in the physical space. The model is able to describe the phenomena taking place in the reservoir even in complex situations, i.e. in the presence of heterogeneities and permeability barriers, demonstrating the flexibility of the finite volume method when simulating non-conventional tests. The results are presented in comparison with those obtained with the finite difference numerical approach and with analytical methods, if possible.

关键词： Finite volume method numerical methods horizontal well modeling injection testing gridding

Long-noncoding RNAs as epigenetic regulators in neurodegenerative diseases

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Neural Regeneration Research 2023年第6期18卷 1243-1248页

作者： Paola Ruffo francesca De Amicis Emiliano Giardina francesca Luisa Conforti Medical Genetics Laboratory Department of PharmacyHealth and Nutritional SciencesUniversity of CalabriaRendeItaly Department of Pharmacy Health and Nutritional SciencesUniversity of CalabriaRendeItaly Genomic Medicine Laboratory UILDM IRCCS Fondazione Santa LuciaRomeItaly Department of Biomedicine&Prevention Tor Vergata University of RomeRomeItaly

The growing and rapid development of high-throughput sequencing technologies have allowed a greater understanding of the mechanisms underlying gene expression *** the epigenome and epitranscriptome directs the fate of the transcript influencing the functional outcome of each *** this context,non-coding RNAs play a decisive role in addressing the expression regulation at the gene and chromosomal ***-noncoding RNAs,consisting of more than 200 nucleotides,have been shown to act as epigenetic regulators in several key molecular processes involving neurodegenerative disorders,such as Alzheimer’s disease,Parkinson’s disease,amyotrophic lateral sclerosis and Huntington’s ***-noncoding RNAs are abundantly expressed in the central nervous system,suggesting that their deregulation could trigger neuronal degeneration through RNA *** evaluation of their diagnostic significance and therapeutic potential could lead to new treatments for these diseases for which there is no cure.

关键词： Alzheimer’s disease amyotrophic lateral sclerosis epigenetic mechanism Huntington’s disease long-noncoding RNAs neurodegenerative disease non-coding RNAs Parkinson’s disease

Chronic kidney disease as a predictor of clinical risk in the elderly

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Journal of Geriatric Cardiology 2016年第3期13卷 199-201页

作者： francesca Viazzi francesca Cappadona Barbara Bonino Roberto Pontremoli University of Genoa and IRCCS AOU San Martino-IST Genoa Italy

Facing the needs of an increasingly ageing population is rapidly becoming a major public health issue in western countries, Chronic kidney disease （CKD）, whose current prevalence is estimated around 10%-15% in the general population, with considerably higher figures in at-risk groups, is widely known to increase with age. In the elderly, renal impairment is often concomitant or secondary to several other systemic disorders such as hypertension, atherosclerosis,

关键词： Albuminuria Chronic kidney disease Glomerular filtration rate Risk assessment The elderly

Is it possible to develop a cerebellar reserve?

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Neural Regeneration Research 2022年第5期17卷 994-996页

作者： francesca Gelfo Laura Petrosini Department of Human Sciences Guglielmo Marconi UniversityRomeItaly IRCCS Fondazione Santa Lucia RomeItaly

The concept of neural plasticity accounts for the now well clarified brain ability to react to internal and external stimuli by transforming its structure and *** translation of whatever experience in specific electrical signals that run through our neural networks induces a number of plastic changes at both functional and structural levels.

关键词： function. translation clarified

SPL transcription factors prevent inflorescence reversion in rice

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Molecular Plant 2021年第7期14卷 1041-1043页

作者： francesca Giaume Fabio Fornara Department of Biosciences University of MilanVia Celoria 2620133 MilanItaly

Plants show an incredible diversity of forms,dimensions,archi-tectures,structures,and reproductive ***,they can be geometrically described as composed of simple building units called phytomers,which are produced by the shoot apical meri-stem(SAM).A phytomer is made up of a node bearing a leaf and an axillary meristem,and of an internode connecting the node to the following *** of phytomers creates the plant body,similarly to a LEGO construction made of simple *** of the phytomeric unit creates *** leaf can change in size and shape;the axillary meristem can be dormant or active,determinate or indeterminate;the internode can elongate considerably,or be compressed to the extent it might look invisible.

关键词： connecting dimensions visible

Intestinal microbiota in inflammatory bowel disease:Friend of foe?

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World Journal of Gastroenterology 2011年第5期17卷 557-566页

作者： francesca Fava Silvio Danese Inflammatory Bowel Disease Unit Istituto Clinico HumanitasVia Manzoni 11320089 RozzanoMilanoItaly

Inflammatory bowel disease （IBD） arises from disruption of immune tolerance to the gut commensal microbiota, leading to chronic intestinal inflammation and mucosal damage in genetically predisposed hosts. In healthy individuals the intestinal microbiota have a symbiotic relationship with the host organism and possess important and unique functions, including a metabolic function （i.e. digestion of dietary compounds and xenobiotics, fermentation of undigestible carbohydrates with production of short chain fatty acids）, a mucosal barrier function （i.e. by inhibiting pathogen invasion and strengthening epithelial barrier integrity）, and an immune modula- tory function （i.e. mucosal immune system priming and maintenance of intestinal epithelium homeostasis）. A fine balance regulates the mechanism that allows co- existence of mammals with their commensal bacteria. In IBD this mechanism of immune tolerance is impaired because of several potential causative factors. The gut microbiota composition and activity of IBD patients are abnormal, with a decreased prevalence of dominant members of the human commensal microbiota （i.e. Clostridium IXa and IV groups, Bacteroides, bifldobacteria） and a concomitant increase in detrimental bacteria （i.e. sulphate-reducing bacteria, Escherichia coll. The observed dysbiosis is concomitant with defectiveinnate immunity and bacterial killing （i.e. reduced mucosal defensins and IgA, malfunctioning phagocytosis） and overaggressive adaptive immune response （due to ineffective regulatory T cells and antigen presenting cells）, which are considered the basis of IBD pathogen- esis. However, we still do not know how the interplay between these parameters causes the disease. Studies looking at gut microbial composition, epithelial integrity and mucosal immune markers in genotyped IBD populations are therefore warranted to shed light on this obscure pathogenesis.

关键词： Microbiota Inflammatory bowel disease Microbial dysbiosis Immune tolerance Innate immu-nity Mucosal barrier

Pluripotent stem cell derived inhibitory interneurons–principles and applications in health and disease

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Neural Regeneration Research 2020年第2期15卷 251-252页

作者： francesca Keefe Meng Li Neuroscience and Mental Health Research Institute School of Medicine and School of Bioscience Cardiff University

Inhibitory interneurons are gamma-aminobutyric acid-ergic (GABAergic) nerve cells that act to maintain the appropriate excitation-inhibition balance, and synchronise the output of principle cells to generate rhythmic patterns of firing (Kessaris et al., 2014). This critical role, along with their brain-wide distribution, has led to the implication of interneurons in many neuropathologies, including schizophrenia, autism, dystonia and epilepsies (Marín, 2012).

关键词： cells act has led

Membraneless organelles restructured and built by pandemic viruses:HIV-1 and SARS-CoV-2

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Journal of Molecular Cell Biology 2021年第4期13卷 259-268页

作者： Viviana Scoca francesca Di Nunzio Advanced Molecular Virology and Retroviral Dynamics Group Department of VirologyPasteur InstituteParisFrance BioSPC Doctoral School Universite de ParisParisFrance

Viruses hijack host functions to invade their target cells and spread to new ***,viruses learned to usurp liquid-liquid phase separation(LLPS),a newly exploited mechanism,used by the cell to concentrate enzymes to accelerate and confine a wide variety of cellular *** gives rise to actual membraneless organelles(MLOs),which do not only increase reaction rates but also act as a filter to select molecules to be retained or to be excluded from the liquid *** is exactly what seems to happen with the condensation of SARS-CoV-2 nucleocapsid protein to favor the packaging of intact viral genomes,excluding viral subgenomic or host cellular *** older pandemic virus,HIV-1,also takes advantage of LLPS in the host cell during the viral *** discoveries highlighted that HIV-1 RNA genome condensates in nuclear MLOs accompanied by specific host and viral proteins,breaking the dogma of retroviruses that limited viral synthesis exclusively to the cytoplasmic *** fundamental properties of viral/host LLPS remain still *** studies will contribute to deeply understanding the role of pathogen-induced MLOs in the epidemic invasion of pandemic viruses.

关键词： LLPS MLO HIV-1 SARS-CoV-2

Unsteady Inflow Effects on the Wake Shed from a High-Lift LPT Blade Subjected to Boundary Layer Laminar Separation

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Journal of Thermal Science 2012年第2期21卷 97-108页

作者： francesca Satta Marina Ubaldi Pietro Zunino Università degli Studi di Genova

An experimental investigation on the near and far wake of a cascade of high-lift low-pressure turbine blades subjected to boundary layer separation over the suction side surface has been carried out, under steady and unsteady inflows. Two Reynolds number conditions, representative of take-off/landing and cruise operating conditions of the real engine, have been tested. The effect of upstream wake-boundary layer interaction on the wake shed from the profile has been investigated in a three-blade large-scale linear turbine cascade. The comparison between the wakes shed under steady and unsteady inflows has been performed through the analysis of mean velocity and Reynolds stress components measured at midspan of the central blade by means of a two-component crossed miniature hot-wire probe. The wake development has been analyzed in the region between 2% and 100% of the blade chord from the central blade trailing edge, aligned with the blade exit direction. Wake integral parameters, half-width and maximum velocity defects have been evaluated from the mean velocity distributions to quantify the modifications induced on the vane wake by the upstream wake. Moreover the thicknesses of the two wake shear layers have been considered separately in order to identify the effects of Reynolds number and incoming flow on the wake shape. The self-preserving state of the wake has been looked at, taking into account the different thicknesses of the two shear layers. The evaluation of the power density spectra of the velocity fluctuations allowed the study of the wake unsteady behavior, and the detection of the effects induced by the different operating conditions on the trailing edge vortex shedding.

关键词： Wake-wake unsteady interaction high-lift blade profiles low-pressure turbine blade wake.