6,239 research outputs found
Sulle orme del consumatore affinity analysis e knowledge visualization per il processo decisionale
L\u2019articolo analizza i reali comportamenti di acquisto dell\u2019acquirente all\u2019interno del punto vendita e individua i pattern latenti pi\uf9 significativi attraverso un\u2019analisi di affinit\ue0 di 128.364 scontrini estratti da un dataset di 715.662 transazioni effettuate in un anno. Lo studio individua le strutture associative pi\uf9 ricorrenti relativamente alla singola merceologia. Attraverso la tecnica della Market Basket Analysis \ue8 stato possibile individuare le categorie merceologiche che creano \u201cpoli d\u2019attrazione\u201d sul punto vendita stimolando acquisti di altre categorie. In particolar modo, applicando le regole associative sul punto vendita \ue8 stato possibile identificare le \u201caree calde\u201d e le \u201caree fredde\u201d. L\u2019articolo evidenzia quindi alcune riflessioni sulle strategie che possono adottare gli store manager
Modeling and simulation of a digital control design approach for power supply systems
Electronic designers need to model and simulate system features as close as possible to its effective behaviour. Moreover, today, electronics systems are often composed of mixed analog and digital components. The increasing complexity has led to the use of different simulation softwares, each one specific for a particular level of abstraction: mathematical, circuital, behavioural, etc. In order to simulate the entire system these softwares should work together: co-simulation is necessary for digitally controlled power electronics systems. In this paper, the modeling of a digitally controlled switching power supply system using MATLAB/Simulink, ALDEC Active-HDL and Powersys PSIM is presented. The power converter is modelled in PSIM, the digital control is described in VHDL by using Active-HDL, and the complete system is simulated in MATLAB/Simulink environment. This design approach presents all the advantages of each used software and all its features will be discussed. The comparison between simulation and experimental results of the digitally controlled step-down converter prototype are reported
Cognitive Health of Nonagenarians in Southern Italy: A Descriptive Analysis from a Cross-Sectional, Home-Based Pilot Study of Exceptional Longevity (Cilento Initiative on Aging Outcomes Or CIAO).
Background: Nonagenarians and centenarians (NCs) are an extremely fragile population, particularly in regard to their physical and cognitive function. The aim of this study was to define the neurocognitive profiles among 29 NCs and their 49 younger cohabitants aged 50-75 years from The Cilento Initiative on Aging Outcomes (CIAO) Pilot study in the South of Italy that had provided initial hypotheses regarding positive psychological traits related to exceptional longevity. Methods: During the home visits, lifestyle information with specific questionnaires, functional autonomy and the neuropsychological Mini Mental Scale Examination (MMSE), and the Alzheimer's Disease Assessment Scale-Cognitive (ADAS-Cog) scale were obtained by qualified study personnel. The total blood oxidative capacity was also determined by testing the reactive derivative of oxygen metabolites (d-ROM) and by the Biological Antioxidant Potential (BAP). In all individuals, the APOE genotype determination was also performed. Results: All the subjects in both groups showed high adherence to the Mediterranean Diet. None of the NCs had severe cognitive impairment, and a very low incidence of dementia was found. The data obtained on the Activities ed Instrumental Activities of Daily Living (ADL-IADL) scale showed that the majority of NCs (16/29) were autonomous in daily life activities. The comparative assessment of NCs and cohabitants showed no significant differences in the laboratory assessment of oxidative stress and APOE genotype. Conclusion: In the Cilento Region of Southern Italy, NCs seemed to have good cognitive status when compared to younger cohabitants aging 50-65 years without significant differences in oxidative stress markers or APOE genotype. These results might be related to optimal adherence to the Mediterranean diet, although other lifestyle factors and positive personality traits may also contribute to their healthy aging. Further studies on a larger population should be performed to confirm the results of this pilot study
A High-Throughput Mechanical Activator for Cartilage Engineering Enables Rapid Screening of in vitro Response of Tissue Models to Physiological and Supra-Physiological Loads
Articular cartilage is crucially influenced by loading during development, health, and disease. However, our knowledge of the mechanical conditions that promote engineered cartilage maturation or tissue repair is still incomplete. Current in vitro models that allow precise control of the local mechanical environment have been dramatically limited by very low throughput, usually just a few specimens per experiment. To overcome this constraint, we have developed a new device for the high throughput compressive loading of tissue constructs: the High Throughput Mechanical Activator for Cartilage Engineering (HiT-MACE), which allows the mechanoactivation of 6 times more samples than current technologies. With HiT-MACE we were able to apply cyclic loads in the physiological (e.g., equivalent to walking and normal daily activity) and supra-physiological range (e.g., injurious impacts or extensive overloading) to up to 24 samples in one single run. In this report, we compared the early response of cartilage to physiological and supra-physiological mechanical loading to the response to IL-1β exposure, a common but rudimentary in vitro model of cartilage osteoarthritis. Physiological loading rapidly upregulated gene expression of anabolic markers along the TGF-β1 pathway. Notably, TGF-β1 or serum was not included in the medium. Supra-physiological loading caused a mild catabolic response while IL-1β exposure drove a rapid anabolic shift. This aligns well with recent findings suggesting that overloading is a more realistic and biomimetic model of cartilage degeneration. Taken together, these findings showed that the application of HiT-MACE allowed the use of larger number of samples to generate higher volume of data to effectively explore cartilage mechanobiology, which will enable the design of more effective repair and rehabilitation strategies for degenerative cartilage pathologies
A matrix model for the topological string II: The spectral curve and mirror geometry
In a previous paper, we presented a matrix model reproducing the topological
string partition function on an arbitrary given toric Calabi-Yau manifold.
Here, we study the spectral curve of our matrix model and thus derive, upon
imposing certain minimality assumptions on the spectral curve, the large volume
limit of the BKMP "remodeling the B-model" conjecture, the claim that
Gromov-Witten invariants of any toric Calabi-Yau 3-fold coincide with the
spectral invariants of its mirror curve.Comment: 1+37 page
X-Y aneuploidy rate in sperm of two ‘minor’ breeds of cattle (Bos taurus) by using dual color fluorescent in situ hybridization (FISH)
Differential alterations of the concentrations of endocannabinoids and related lipids in the subcutaneous adipose tissue of obese diabetic patients.
Statistics of non-linear stochastic dynamical systems under L\'evy noises by a convolution quadrature approach
This paper describes a novel numerical approach to find the statistics of the
non-stationary response of scalar non-linear systems excited by L\'evy white
noises. The proposed numerical procedure relies on the introduction of an
integral transform of Wiener-Hopf type into the equation governing the
characteristic function. Once this equation is rewritten as partial
integro-differential equation, it is then solved by applying the method of
convolution quadrature originally proposed by Lubich, here extended to deal
with this particular integral transform. The proposed approach is relevant for
two reasons: 1) Statistics of systems with several different drift terms can be
handled in an efficient way, independently from the kind of white noise; 2) The
particular form of Wiener-Hopf integral transform and its numerical evaluation,
both introduced in this study, are generalizations of fractional
integro-differential operators of potential type and Gr\"unwald-Letnikov
fractional derivatives, respectively.Comment: 20 pages, 5 figure
Nandrolone decanoate interferes with testosterone biosynthesis altering blood-testis barrier components
The aim of this study was to investigate whether nandrolone decanoate (ND) use affects testosterone production and testicular morphology in a model of trained and sedentary mice. A group of mice underwent endurance training while another set led a sedentary lifestyle and were freely mobile within cages. All experimental groups were treated with either ND or peanut oil at different doses for 6 weeks. Testosterone serum levels were measured via liquid chromatography-mass spectrometry. Western blot analysis and quantitative real-time PCR were utilized to determine gene and protein expression levels of the primary enzymes implicated in testosterone biosynthesis and gene expression levels of the blood-testis barrier (BTB) components. Immunohistochemistry and immunofluorescence were conducted for testicular morphological evaluation. The study demonstrated that moderate to high doses of ND induced a diminished serum testosterone level and altered the expression level of the key steroidogenic enzymes involved in testosterone biosynthesis. At the morphological level, ND induced degradation of the BTB by targeting the tight junction protein-1 (TJP1). ND stimulation deregulated metalloproteinase-9, metalloproteinase-2 (MMP-2) and the tissue inhibitor of MMP-2. Moreover, ND administration resulted in a mislocalization of mucin-1. In conclusion, ND abuse induces a decline in testosterone production that is unable to regulate the internalization and redistribution of TJP1 and may induce the deregulation of other BTB constituents via the inhibition of MMP-2. ND may well be considered as both a potential inducer of male infertility and a potential risk factor to a low endogenous bioavailable testosterone
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