DFT + U Study of structural, electronic, optical and magnetic properties of LiFePO4 Cathode materials for Lithium-Ion batteries

In this study, we have employed a DFT+U calculation using quantum-espresso (QE) code to investigate the structural, electronic, optical, and magnetic properties of LiFePO$\rm_{4}$ cathode material for Li-ion batteries. Crystals of LiFePO$\rm_{4}$ and related materials have recently received a lot of attention due to their very promising use as cathodes in rechargeable lithium-ion batteries. The structural optimization was performed and the equilibrium parameters such as the lattice constants, and the bulk modulus are calculated using QE code and found to be a=4.76 {\AA}, b=6.00 {\AA}, c=10.28 {\AA}, B=90.2 GPa, respectively. The projected density of states (PDOS) for the LiFePO$\rm_{4}$ material is remarkably similar to experimental results in literature showing the transition metal $3d$ states forming narrow bands above the O $2p$ band. The results of the various spin configurations suggested that the ferromagnetic configuration can serve as a useful approximation for studying the general features of these systems. In the absence of Li, the majority spin transition metal $3d$ states are well-hybridized with the O 2p band in FePO$\rm_{4}$. The result obtained with a DFT + U showed that LiFePO4 is direct band gap materials with a band gap of 3.82 eV, which is within the range of the experimental values. The PDOS analyses show qualitative information about the crystal field splitting and bond hybridization and help rationalize the understanding of the structural, electronic, optical, and magnetic properties of the LiFePO$\rm_{4}$ as a novel cathode material. On the basis of the predicted optical absorbance, reflection, refractive index, and energy loss function, LiFePO$\rm_{4}$ is demonstrated to be viable and cost-effective, which is very suitable as a cathode material for Li-ion battery

Hartowanie serca w kardiochirurgii

Cardiac surgery is associated with ischaemic and reperfusion injury to the myocardium. It seems natural to seek a possibility of inducing the natural endoprotective mechanisms known as myocardial conditioning, including preconditioning, postconditioning, and remote conditioning. Still, in spite of almost 20 years of research in the field, we are far from routine widespread usage of these methods, with published reports describing quite various, and often contradictory results. Current review summarises the trials of using the conditioning in cardiac surgical practice including pharmacological manipulations to induce resistance to ischaemia-reperfusion. Kardiol Pol 2011; 69, supl. III: 80–84Zabieg kardiochirurgiczny wiąże się z uszkodzeniem niedokrwienno-reperfuzyjnym mięśnia sercowego. Wzbudzenie mechanizmów endoprotekcyjnych, takich jak hartowanie niedokrwieniem, hartowanie reperfuzją i hartowanie na odległość, wydaje się oczywistym kierunkiem działań zmierzających do ochrony mięśnia sercowego w trakcie operacji. Niemniej mimo niemal 20 lat, jakie minęły od pierwszej próby planowego hartowania mięśnia sercowego w kardiochirurgii, mechanizmy te nie doczekały się powszechnego zastosowania klinicznego. Wyniki uzyskiwane przez różnych autorów są dość rozbieżne, a czasem wręcz sprzeczne. W niniejszej pracy streszczono próby klinicznego wykorzystania hartowania w kardiochirurgii, w tym próby farmakologicznego wzbudzenia oporności na szkodę niedokrwienno-reperfuzyjną. Kardiol Pol 2011; 69, supl. III: 80–8

Automated Decision Support and Guideline Verification in Clinical Practice

Applying international guidelines in medical, including cardiological, therapies is a guarantee of safe and modern treatment. Unfortunately, standards are often not obeyed. In this paper we present an experimental software program based on rough sets methods. The main aim of this application is to improve patient care and help the decision process using guidelines verification. We concentrate on the practical aspects using these methods. Examples and clinical tests, which were based on real-life data of our patients, show that the accuracy of results reached on a large group of patients could be acceptable in clinical practice. 1

The co-application of hypoxic preconditioning and postconditioning abolishes their own protective effect on systolic function in human myocardium

Background: Ischemic preconditioning (IPC) and postconditioning (POC) are well documented to trigger cardioprotection against ischemia/reperfusion (I/R) injury, but the effect oftheir both co-application remains unclear in human heart. The present study sought to assessthe co-application of IPC and POC on fragments of human myocardium in vitro.Methods: Muscular trabeculae of the human right atrial were electrically driven in the organbath and subjected to simulated I/R injury – hypoxia/re-oxygenation injury in vitro. To achieveIPC of trabeculae the single brief hypoxia period preceded the applied lethal hypoxia, and to achieve POC triple brief hypoxia periods followed the lethal hypoxia. Additional muscular trabeculae were exposed only to the hypoxic stimulation (Control) or were subjected to the non-hypoxic stimulation (Sham). 10 μM norepinephrine (NE) application ended every experiment to assess viability of trabeculae. The contraction force of the myocardium assessed as a maximal amplitude of systolic peak (%Amax) was obtained during the whole experiment’s period.Results: Co-application of IPC and POC resulted in decrease in %Amax during the re-oxygentaionperiod and after NE application, as compared to Control (30.35 ± 2.25 vs. 41.89 ± 2.25, 56.26 ± 7.73 vs. 65.98 ± 5.39, respectively). This was in contrary to the effects observed when IPC and POC were applied separately.Conclusions: The co-application of IPC and POC abolishes the cardioprotection of either intervention alone against simulated I/R injury in fragments of the human right heart atria

a prospective ‘before/after’ cohort study

Objectives Antibiotic resistance has risen dramatically over the past years. For individual patients, adequate initial antibiotic therapy is essential for clinical outcome. Computer-assisted decision support systems (CDSSs) are advocated to support implementation of rational anti-infective treatment strategies based on guidelines. The aim of this study was to evaluate long- term effects after implementation of a CDSS. Design This prospective ‘before/after’ cohort study was conducted over four observation periods within 5 years. One preinterventional period (pre) was compared with three postinterventional periods: directly after intensive implementation efforts (post1), 2 years (post2) and 3 years (post3) after implementation. Setting Five anaesthesiological-managed intensive care units (ICU) (one cardiosurgical, one neurosurgical, two interdisciplinary and one intermediate care) at a university hospital. Participants Adult patients with an ICU stay of >48 h were included in the analysis. 1316 patients were included in the analysis for a total of 12 965 ICU days. Intervention Implementation of a CDSS. Outcome measures The primary end point was percentage of days with guideline adherence during ICU treatment. Secondary end points were antibiotic-free days and all-cause mortality compared for patients with low versus high guideline adherence. Main results Adherence to guidelines increased from 61% prior to implementation to 92% in post1, decreased in post2 to 76% and remained significantly higher compared with baseline in post3, with 71% (p=0.178). Additionally, antibiotic-free days increased over study periods. At all time periods, mortality for patients with low guideline adherence was higher with 12.3% versus 8% (p=0.014) and an adjusted OR of 1.56 (95% CI 1.05 to 2.31). Conclusions Implementation of computerised regional adapted guidelines for antibiotic therapy is paralleled with improved adherence. Even without further measures, adherence stayed high for a longer period and was paralleled by reduced antibiotic exposure. Improved guideline adherence was associated with reduced ICU mortality

Risk factors for diabetic foot ulcers: An Albanian retrospective study of inpatients with type 2 diabetes

OBJECTIVE: The aim of this study was to assess the impact of glucose control, diabetes-related complications and cardiometabolic risk factors on the risk of diabetic foot ulcers (DFUs) and DFU complications in Albanian adult inpatients with T2D.PATIENTS AND METHODS: We conducted a retrospective case-control study on 482 Albanian adult inpatients with T2D. DFU was defined as a full-thickness skin lesion requiring >= 14 days for healing and was classified at the time of hospital admission. Demographic and biochemical parameters of the study participants, the presence of comorbidities and diabetes -related complications at the time of hospital admission were evaluated through a retrospective chart review.RESULTS: Mean age of study participants was 54.8 +/- 10.7 years. Participants (284 males and 198 females) were divided into two groups: DFU (cases; n=104) and non-DFU (controls; n=378). Multivariate analysis (performed by a logistic regression model) revealed that the most relevant independent variables associated with DFU were BMI [OR= 0.62; p=0.007], HDL-cholesterol [OR=0.00; p<0.0001], triglycerides [OR=7.48; p=0.0004], cigarette smoking [OR=26.46; p=0.005], duration of diabetes [OR=1.53; p<0.0001], fasting plasma glucose (FPG) [OR=1.06; p<0.0001], systolic blood pressure (SBP) [OR=1.13; p=0.0004] and insulin therapy alone [OR=0.11; p=0.02]. ROC curve analysis showed that FPG (AUC=0.83), glycated hemoglobin (HbA1c) (AUC=0.75), triglycerides (AUC=0.78) and HDL-cholesterol (AUC=0.82) were the most reliable biomarkers able to detect DFU. In the DFU group, the most relevant independent variables associated with previous minor lower-extremity amputations (LEAs) were represented by HbA1c [OR=1.47; p=0.03], age <55 years [OR=0.12; p=0.0 5] and female sex [OR=4.18; p=0.03]; whereas the most relevant independent variables associated with diabetic peripheral neuropathy (DPN) were HbA1c [OR=1.70; p=0.006], SBP [OR=1.08; p=0.05], BMI [OR=1.20; p=0.03] and lack of cigarette smoking [OR=0.07; p=0.01]. Correlation analysis (performed through the nonparametric Spearman's rank correlation test or through the parametric Pearson test, as appropriate) revealed a significant positive relationship between HbA1c and FPG (r=0.58; p<0.0001), ulcer surface area (r=0.50; p<0.0001), ulcer grade (r= 0.23; p=0.02), minor LEAs (r=0.20; p=0.04), DPN (r=0.41; p<0.0001), and metformin therapy alone (r=0.72; p<0.0001). There was a significant inverse correlation between HbA1c and insulin therapy alone (r=-0.31; p=0.01) and combined metformin and insulin therapy (r=-0.60; p<0.0001). Both DFU and non-DFU groups exhibited suboptimal mean LDL-cholesterol levels (>100 mg/dl) and mean HbA1c values >7.5%. Moreover, in DFU group HbA1c values were markedly elevated (>= 10%) particularly in patients with a grade 3 ulcer and an ulcer surface area >= 4 cm2, as well as in patients with history of minor LEAs and in patients affected by DPN.CONCLUSIONS: The present study suggested that longer duration of diabetes, cigarette smoking, lower HDL-cholesterol levels, poor glucose control, and elevated triglyceride and SBP values may all represent major risk factors for the development of DFU in Albanian patients with T2D. Thus, community interventions and health policies aimed to improve the management of diabetes and related cardiometabolic risk factors should be urgently implemented in Albania, in order to prevent DFUs and other diabetes complications in patients with T2D