Analysis of a Lennard-Jones fcc structure melting to the corresponding frozen liquid: differences between the bulk and the surface

We computed a Lennard Jones frozen liquid with a free surface using classical molecular dynamics. The structure factor curves on the free surface of this sample was calculated for different depths knowing that we have periodic boundary conditions on the other parts of the sample. The resulting structure factor curves show an horizontal shift of their first peak depending on how deep in the sample the curves are computed. We analyze our resulting curves in the light of spatial correlation functions during melting and at when the liquid is frozen. The conclusion is that near the free surface the sample is less dense than in the bulk and that the frozen liquid surface has a spatial correlation which does not differ very much from that of the bulk. This result is intrinsic to the melting of the Lennard Jones liquid and does not depend on any other parameter.Comment: 18 pages 9 figure

Changes in clinical characteristics and outcomes of patients admitted to inpatient cardiac rehabilitation

Aims: Cardiac rehabilitation (CR) have proven to be effective and beneficial in middle-aged and older patients. However, solid data in large cohorts of elderly individuals are yet to be explored. This retrospective study investigated the general characteristics, outcomes, and the level of re-sponse of patients referred to CR over 13 consecutive years. Methods: We reviewed the medical records of patients admitted to Villa Pineta Rehabilitation Hospital for exercise-based CR from 2006 to 2018. Patients’ baseline characteristics and changes following CR in upper limb weight-lifting test (ULW), 30-second sit-to-stand test (30STS), and the 6-minute walking test (6MWT) with associated Borg-related dyspnea (D) and fatigue (F) were collected. We also calculated the number of individuals reaching the minimal clinically relevant change (MCRC) following CR for each outcome. Results: 1551 patients (70.2 ± 9.7 years, 66% men) with complete data set were in-cluded in the analysis. Coronary artery bypass graft and cardiac valve replacement surgery were the most frequent surgical procedures leading to CR referral (41.1% and 35.8%, respectively). The patients’ age (p = 0.03), number of total comorbidities (p < 0.0001), and post-surgical complica-tions (p = 0.02) significantly increased over time. In contrast, the average absolute changes in ULW, 30STS and 6MWT with associated D and F, and the proportion of patients reaching the re-spective MCRC, remained constant over the same period. Conclusion: Patients admitted to exer-cise-based CR were older and had more comorbidities and complications over time. Outcomes, however, were not influenced in terms of absolute change nor clinically meaningful response

Progress in Alternative Strategies to Combat Antimicrobial Resistance: Focus on Antibiotics

Antibiotic resistance, and, in a broader perspective, antimicrobial resistance (AMR), continues to evolve and spread beyond all boundaries. As a result, infectious diseases have become more challenging or even impossible to treat, leading to an increase in morbidity and mortality. Despite the failure of conventional, traditional antimicrobial therapy, in the past two decades, no novel class of antibiotics has been introduced. Consequently, several novel alternative strategies to combat these (multi-) drug-resistant infectious microorganisms have been identified. The purpose of this review is to gather and consider the strategies that are being applied or proposed as potential alternatives to traditional antibiotics. These strategies include combination therapy, techniques that target the enzymes or proteins responsible for antimicrobial resistance, resistant bacteria, drug delivery systems, physicochemical methods, and unconventional techniques, including the CRISPR-Cas system. These alternative strategies may have the potential to change the treatment of multi-drug-resistant pathogens in human clinical settings

A nutritional approach to the prevention of cancer: from assessment to personalized intervention

Among lifestyle factors, nutrition is one of the most important determinants of health, and represents a pivotal element of cancer risk. Nonetheless, epidemiological evidences of the relationship between several cancers and specific foods and nutrients is still inadequate, and solid conclusions are missing. Indeed, caloric restriction without malnutrition is associated to cancer prevention. Food may be also the primary route of exposure to contaminants such as metals, persistent organic pollutants, and pesticides. Exposuredisease associations and the interplay with genetic susceptibility requires further studies on genetic variation, environment, lifestyle, and chronic disease in order to eliminate and reduce associated health risks, thus contributing to improve health outcomes for the population. A primary nutritional approach for Active and Healthy Ageing (AHA) has been developed by the Nutrition group of the European Innovation Partnership (EIP) on AHA. The working group on lifestyles of the Italian Ministry of Health has developed a comprehensive approach to adequate nutrition using a consensus methodology to collect and integrate the available evidences from the literature and from the Italian experiences at the regional level, to raise the interest of other experts and relevant stakeholders to outline and scale-up joint strategies for a primary nutritional approach to cancer prevention

From landfill to water, land and life: the creation of the Centre for stone materials aimed at secondary processing

This paper focuses on the creation of a Centre for the recycling of stone materials. The Centre will be able to offer a range of activities amongst which is the improvement of the production chain of the Orosei Marble district in Sardinia, Italy. Several companies operate within the marble producing area, specializing in both quarrying and stone processing. They have formed a Consortium in order to rehabilitate an area of more than 17 ha. The restoration will be carried out through an environmentally sustainable procedure. The area was previously used as a landfill for waste deriving from marble quarrying and processing. At that time unshaped blocks of various sizes (which are unsuitable to block-cutter sawing), waste deriving from both block sawing and slab/strip cutting (such as broken slabs, strips, tiles) and microfine dust from filter presses of water treatment plants were representing an environmental problem. The local administration was struggling to find new areas which could be used for landfills, resulting in an additional cost for the landfill, ultimately affecting the variable production costs. The project involves the building of a venue to be used for temporary storage, treatment of wastes produced by both quarrying and primary processing, in order to make them suitable as secondary raw materials. The project also deals with the catch basin hydrology of the area involved in the project, the building of a multifunctional centre, the landscaping and other environmental features such as vehicle traffic and slopes greening

Probing the fate of interstitial water in bulk bioactive glass by ab-initio simulations

As also observed for conventional silicate glasses, water can be incorporated in the bulk interstitial regions of a bioactive glass (BG) matrix during the glass preparation and/or upon exposure to an aqueous environment. However, in the case of BGs, very little is known about the effect of hydration on the bulk structure, and then on key properties of these materials, such as biodegradation and bioactivity, that depend on the bulk structure itself. Here we employ a combination of atomistic simulation techniques to explore the nature and effects of water-BG interactions in the bulk of a bioactive glass. The fate of water inserted in the bulk interstitial region of 45S5 bioglass has been studied by ab initio geometry relaxations and Molecular Dynamics (AIMD) simulations. We probed the interaction of a water molecule with silica rings and cages of different size, as well as the stability of potentially relevant configurations involving manually dissociated water and opened rings. The local stability of selected configurations was further assessed by subjecting them to AIMD runs, in order to overcome possible kinetic barriers for water diffusion and dissociation. Small rings do not appear as favourable absorption sites in the bulk of a bioactive glass as they are for bioinert glasses. Moreover, water dissociation through rupture of Si-O bonds of silica rings formed in the bulk was thermodynamically unfavourable. However, a high-temperature AIMD run led to a dissociated state involving no broken Si-O bonds and a free hydroxyl: because re-optimization of this state produced the most favourable hydration energy identified in this study, dissociative absorption through this mechanism appears a likely outcome of the water-45S5 interaction at low water content. We discuss the structural and dynamical basis for the stability of this and other water-glass adducts identified, and the potential consequences of these interactions for the behaviour of the glass in a biological contex