Assessment of a desiccant cooling system in a traditional and innovative nanofluid HVAC system

The topic of energy saving is a constant in everyday life, and it is widespread all over the world. Space heating using solar panels is the most used renewable source of energy, but the application of solar energy for cooling the fluids used for refrigeration is growing very fast. Among the techniques used for refrigeration, this work focused on Desiccant Cooling. In particular, with the use of dynamic simulation software, it was possible to study the heat supplied and the energy consumption of a Heating Ventilation Air Conditioning (HVAC) system of a university building and to compare consumption with those of a Desiccant Cooling system applied to the same building. Four different cases were simulated: two related to the HVAC system, one of which operates with water and glycol and the other one with nanofluid, and the other ones to the Desiccant Cooling system with both types of fluids mentioned above. Keeping the same energy demand of the building in all the simulations, it was found that in summer the Desiccant Cooling system had higher performance than the traditional HVAC system and that the use of the nanofluid in both types of conditioning systems further increased the performance of 21%. Simulations were carried out using TRNSYS software

Ground state of excitons and charged excitons in a quantum well

A variational calculation of the ground state of a neutral exciton and of positively and negatively charged excitons (trions) in single quantum well is presented. We study the dependance of the correlation energy and of the binding energy on the well width and on the hole mass. Our results are are compared with previous theoretical results and with avalaible experimental data.Comment: 8 pages, 5 figures presented to OECS

Development of L-Lysine-Loaded PLGA Microparticles as a Controlled Release System for Angiogenesis Enhancement

Vascularization is a highly conserved and considerably complex and precise process that is finely driven by endogenous regulatory processes at the tissue and systemic levels. However, it can reveal itself to be slow and inadequate for tissue repair and regeneration consequent to severe lesions/damages. Several biomaterial-based strategies were developed to support and enhance vasculogenesis by supplying pro-angiogenic agents. Several approaches were adopted to develop effective drug delivery systems for the controlled release of a huge variety of compounds. In this work, a microparticulate system was chosen to be loaded with the essential amino acid L-lysine, a molecule that has recently gained interest due to its involvement in pro-angiogenic, pro-regenerative, and anti-inflammatory mechanisms. Poly (lactic-co-glycolic acid), the most widely used FDA-approved biodegradable synthetic polymer for the development of drug delivery systems, was chosen due to its versatility and ability to promote neovascularization and wound healing. This study dealt with the development and the effectiveness evaluation of a PLGA-based microparticulate system for the controlled release of L-lysine. Therefore, in order to maximize L-lysine encapsulation efficiency and tune its release kinetics, the microparticle synthesis protocol was optimized by varying some processing parameters. All developed formulations were characterized from a morphological and physicochemical point of view. The optimized formulation was further characterized via the evaluation of its preliminary biological efficacy in vitro. The cellular and molecular studies revealed that the L-lysine-loaded PLGA microparticles were non-toxic, biocompatible, and supported cell proliferation and angiogenesis well by stimulating the expression of pro-angiogenic genes such as metalloproteinase-9, focal adhesion kinases, and different growth factors. Thus, this work showed the potential of delivering L-lysine encapsulated in PLGA microparticles as a cost-effective promoter system for angiogenesis enhancement and rapid healing

Mortality and pulmonary complications in patients undergoing surgery with perioperative sars-cov-2 infection: An international cohort study

Background The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (740%) had emergency surgery and 280 (248%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (261%) patients. 30-day mortality was 238% (268 of 1128). Pulmonary complications occurred in 577 (512%) of 1128 patients; 30-day mortality in these patients was 380% (219 of 577), accounting for 817% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 175 [95% CI 128-240], p<00001), age 70 years or older versus younger than 70 years (230 [165-322], p<00001), American Society of Anesthesiologists grades 3-5 versus grades 1-2 (235 [157-353], p<00001), malignant versus benign or obstetric diagnosis (155 [101-239], p=0046), emergency versus elective surgery (167 [106-263], p=0026), and major versus minor surgery (152 [101-231], p=0047). Interpretation Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research

Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study

Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research

The white marble of the cloister of the Real College-Seminar of Corpus Christi in Valencia (Spain): archival researches for de identification of its provenance and diagnostic studies for understanding its decay

White marble and Ribarroja stone are the stone materials employed for the columns, the balustrade and the façades of the cloister of the Real Colegio Seminario of Corpus Christi in Valencia (1586-1611) also called Colegio del Patriarca. The state of conservation of the marble elements of the balustrade is more critical than that of the columns. The lack of data concerning the type and provenance of the marble from both the balustrade and the columns and its chemical-physical characteristics, has probably been the cause of wrong interpretations and wrong choices adopted in the restoration works executed in the 1980s. The data reported in this paper are the preliminary results of an interdisciplinary study based on the analysis of the archival sources and on the diagnostic investigations performed on the constituent materials. The gathered data allowed us to define the provenance of the marble (Carrara, Italy) and to establish the main causes of decay of the elements of the cloister

Effect on insulin sensitivity of Implanon vs. GnRH agonist in women with endometriosis

OBJECTIVES:To evaluate the influence of two medical treatments for endometriosis on insulin sensitivity.STUDY DESIGN:After surgery, 26 women with endometriosis were randomly allocated to a 6-month treatment with a GnRH agonist (Leuprorelin 3.75 mg/28 days) or a subdermal progestin implant (etonogestrel 68 mg). Insulin sensitivity (SI) and glucose utilization independent of insulin (Sg) were investigated at baseline and after 6 months by a frequently sampled intravenous glucose tolerance test (FSIGT) associated with the minimal model method.RESULTS:Both therapies tended to decrease SI, but the effect did not reach statistical significance in the GnRH agonist group (5.43+/-1.29 vs. 3.99+/-0.8) and was significant in the etonogestrel group (5.74+/-1.12 vs. 3.95+/-0,78; p=.046). Sg, fasting glucose, insulin, C-peptide and C-peptide/insulin were not modified by either treatment.CONCLUSIONS:The modifications of glucose-insulin metabolism induced by the GnRH agonist are of no relevance for the short-term use of this molecule. Even if the modification induced by the etonogestrel implant is subtle and of no major impact, it should be taken into consideration for the long-term treatment of individuals with abnormalities of glucose-insulin metabolism

A virtual reality framework for the design review of complex industrial assemblies: case study on the interiors of Superjet 100 aircraft

This work concerns the development of a virtual reality environment aimed at design review of complex industrial assemblies. Virtual reality clearly shows its effectiveness when different and very specialized designers have to interact each other in setting up complex projects. Virtual Design Review (VDR) allows multiple designers to simultaneously analyze and review the project, providing the necessary tools to highlight possible design flaws and make choices in real time. In facts, not only designers, but also production engineers can be involved in the critical review process, according to the concurrent engineering design paradigm. The case study focuses on the design review of the interiors of Superjet 10