1,772 research outputs found

    Replica Fourier Transforms on Ultrametric Trees, and Block-Diagonalizing Multi-Replica Matrices

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    The analysis of objects living on ultrametric trees, in particular the block-diagonalization of 4-replica matrices Mαβ;γδM^{\alpha \beta ; \gamma \delta}, is shown to be dramatically simplified through the introduction of properly chosen operations on those objects. These are the Replica Fourier Transforms on ultrametric trees. Those transformations are defined and used in the present work.Comment: Latex file, 14 page

    Stability of the Mezard-Parisi solution for random manifolds

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    The eigenvalues of the Hessian associated with random manifolds are constructed for the general case of RR steps of replica symmetry breaking. For the Parisi limit RR\to\infty (continuum replica symmetry breaking) which is relevant for the manifold dimension D<2D<2, they are shown to be non negative.Comment: LaTeX, 15 page

    A focus on the transformation processes for the valorization of glycerol derived from the production cycle of biofuels

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    Glycerol is a valuable by-product in the biodiesel industries. However, the increase in biodiesel production resulted in an excess production of glycerol, with a limited market compared to its availability. Precisely because glycerol became a waste to be disposed of, the costs of biodiesel production have reduced. From an environmental point of view, identifying reactions that can con-vert glycerol into new products that can be reused in different applications has become a real neces-sity. According to the unique structural characteristics of glycerol, transformation processes can lead to different chemical functionalities through redox reactions, dehydration, esterification, and ether-ification, with the formation of products that can be applied both at the finest chemical level and to bulk chemistry

    High-Throughput Design of Refractory High-Entropy Alloys: Critical Assessment of Empirical Criteria and Proposal of Novel Guidelines for Prediction of Solid Solution Stability

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    Refractory high-entropy alloys (RHEAs) are a new class of metallic alloys which have been extensively studied in the past decade due to their excellent high-temperature performances. However, the design of new lightweight and ductile RHEAs is a challenging task, since an extensive exploration of the immense compositional space of multicomponent systems is practically impossible. Aiming to reduce the experimental effort, several research groups have proposed different predictive criteria to design new high-performing HEAs. Nevertheless, the criteria proposed so far are often based on a limited amount of data and, generally, do not differentiate between refractory and nonrefractory HEAs. To overcome these limitations, herein, a comprehensive database of properties of 265 RHEAs reported in the open literature from 2010 to 2022 is developed. Such a database is used to assess the validity of predictive empirical criteria and new guidelines for the prediction of solid solution stability in RHEAs are proposed

    Does one size fit all? An update on chronic ventilatory support in different respiratory illnesses

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    Home noninvasive ventilation (HNIV) improves outcomes in different disease categories. In this article, we discuss indications for when and how to initiate HNIV in COPD, obesity hypoventilation syndrome (OHS) and neuromuscular disorders (NMD). While in COPD, significant diurnal hypercapnia and high-intensity HNIV are essential ingredients for success, in NMD and OHS, early respiratory changes are best detected during sleep through oxy-capnography associated (or not) with respiratory polygraphy. In COPD and OHS, it is crucial to consider the coexistence of obstructive sleep apnoea because treatment with continuous positive airway pressure may be the simplest and most effective treatment that should be proposed even in hypercapnic patients as first-line therapy. In NMD, the need for continuous HNIV and eventual switching to tracheostomy ventilation makes this group’s management more challenging. Achieving successful HNIV by improving quality of sleep, quality of life and keeping a good adherence to the therapy is a challenge, above all in COPD patients. In OHS patients, on top of HNIV, initiation of other interventions such as weight loss management is crucial. More resources should be invested in improving all these aspects. Telemonitoring represents a promising method to improve titration and follow-up of HNIV

    An Analysis of the Most Adopted Rating Systems for Assessing the Environmental Impact of Buildings

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    Rating systems for assessing the environmental impact of buildings are technical instruments that aim to evaluate the environmental impact of buildings and construction projects. In some cases, these rating systems can also cover urban-scale projects, community projects, and infrastructures. These schemes are designed to assist project management in making the projects more sustainable by providing frameworks with precise criteria for assessing the various aspects of a building's environmental impact. Given the growing interest in sustainable development worldwide, many rating systems for assessing the environmental impact of buildings have been established in recent years, each one with its peculiarities and fields of applicability. The present work is motivated by an interest in emphasizing such differences to better understand these rating systems and extract the main implications to building design. It also attempts to summarize in a user-friendly form the vast and fragmented assortment of information that is available today. The analysis focuses on the six main rating systems: the Building Research Establishment Environmental Assessment Methodology (BREEAM), the Comprehensive Assessment System for Built Environment Efficiency (CASBEE), the Deutsche Gesellschaft fur Nachhaltiges Bauen (DGNB), the Haute Qualite Environnementale (HQETM), the Leadership in Energy and Environmental Design (LEED), and the Sustainable Building Tool (SBTool)

    Development, Characterization, and In Vitro Evaluation of Tamoxifen Microemulsions

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    Microemulsions (MEs) were designed by an innovative rational development, characterized, and used to load up to 20 mM of Tamoxifen citrate (TMX). They were made with acceptable and well-characterized excipients for all the routes of administration. Some of their properties, such as nanometric mean size and long stability shelf life, make them interesting drug delivery systems. The results obtained after the in vitro inhibition of estradiol-induced proliferation in MCF-7 breast cancer cells demonstrated a significant effect in cell growth. A decreasing of at least 90% in viable cells was shown after the incubation with MEs containing 20 mM of TMX. Besides, two compositions which loaded 10 mM of drug showed a cytotoxic effect higher than 70%. These results encourage the evaluation of alternative protocols for this drug administration, not only for estrogen receptor (ER) positive tumors, but also for ER negative

    Estimations of length-weight relationships and consumption rates of odontocetes in the Mediterranean Sea from stranding data

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    Stranding data provide fundamental information on biometric traits of cetaceans useful to increase knowledge on ecological traits and their consumption patterns. In this study, the length weight (L-W) relationships through the power regression model (W = a ×Lb ) were calculated for three dolphin species (the striped dolphin, the common bottlenose dolphin and the Risso’s dolphin) in several Mediterranean subregions and at the scale of the entire basin. Length (L) and weight (W) data were collected from stranding records during the period from 1983 to 2021 acquired from several databases and the literature. Starting from L-W relationships, a bootstrap method was applied to estimate the mean body weights, the daily ingested biomass (IB) and annual food consumption (AFC) rates of different dolphin species. In particular, four different equations were used to estimate the IB rates. Prey consumption by dolphin species was calculated through AFC rates and the available diet information (expressed in weight fractions) of dolphin species for different Mediterranean subregions. Considering the L-W relationships in the Mediterranean Sea, b coefficient values were equal to 2.578, 2.975 and 2.988 for the striped, the common bottlenose and the Risso’s dolphin, respectively. At the Mediterranean scale, the AFC values estimated were 3913 kg (CI 2469–5306) for the Risso’s dolphin, 2571 kg (1372–3963) for the common bottlenose dolphin and 1118 kg (531–1570) for the striped dolphin. Prey consumption pattern showed a clear partitioning among the investigated species, where the common bottlenose dolphin exploits neritic demersal and pelagic fishes (e.g. eel fishes, sparids), the striped dolphin exploits mesopelagic fishes and myctophids, and the Risso’s dolphin was specialized on bathyal cephalopods of Histioteuthidae family. The results obtained in this study provide new information for the investigated species in several Mediterranean subregions providing a first consistent baseline to support the population dynamics modelling. At the same time, the wide uncertainty ranges of some parameters, as well as the lack of information for some species, stress the necessity of improving the data collection associated to stranding events, especially in the southern Mediterranean areas
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