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Nano-micro-porous skutterudites with 100% enhancement in ZT for high performance thermoelectricity
No full textAbstractIncreasing energy demands require new materials, e.g., thermoelectrics, for efficient energy conversion of fossil fuels. However, their low figure of merit (ZT) limits widespread applications. Nanostructuring has been an effective way of lowering the thermal conductivity. However, grain growth at elevated temperature is still a big concern, for otherwise expected to be long-lasting thermoelectric generators. Here, we report a porous architecture containing nano- to micrometer size irregularly shaped and randomly oriented pores, scattering a wide spectrum of phonons without employing the conventional rattling phenomenon. Lattice thermal conductivity reaches the phonon glass limit. This design yields &$2gt;100% enhancement in ZT, as compared to the pristine sample. An unprecedented and very promising ZT of 1.6 is obtained for Co23.4Sb69.1Si1.5Te6.0 alloy, by far the highest ZT ever reported for un-filled skutterudites, with further benefits, i.e. rare-earth-free and improved oxidation resistance enabling simple processing
Datasets used to discover the microbial signatures of oral dysbiosis, periodontitis and edentulism in humans
No full textAbstractThis article provides supporting data for the research article ‘Microbial Signatures of Oral Dysbiosis, Periodontitis and Edentulism Revealed by Gene Meter Methodology’ (M.C. Hunter, A.E. Pozhitkov, P.A. Noble, 2016) [1]. In that article, we determined the microbial abundance signatures for patient with periodontics, edentulism, or health using Gene Meter Technology. Here we provide the data used to make the DNA microarray and the resulting microbial abundance data that was determined using the calibrated probes and the 16S rRNA genes harvested from patients. The first data matrix contains two columns: one is the GenInfo Identifier (GI) numbers of the 16S rRNA gene sequences and the other is the corresponding oral bacterial taxonomy. The probes were then screened for redundancy and if they were found to be unique, they were synthesized onto the surface of the DNA microarrays. The second data matrix consists of the abundances of the 576 16S rRNA genes that was determined using the median value of all individual calibrated probes targeting each gene. The data matrix consists of 16 columns and 576 rows, with the columns representing the 16 patients and the rows representing 576 different oral microorganisms. The third data matrix consists of the abundances of 567 16S rRNA genes determined using the calibrated abundance of all aggregated probes targeting the same 16S rRNA gene. The data matrix of the aggregated probes consists of 16 samples and 567 rows
Serum TARC levels are strongly correlated with blood eosinophil count in patients with drug eruptions
No full textAbstractBackgroundThis study aims to evaluate the relationship between serum thymus and activation-regulated chemokine (TARC) levels with various clinicopathological conditions in patients with drug eruptions. The value of TARC in diagnosing drug-induced hypersensitivity syndrome (DIHS) was also examined.MethodsStudy participants included 84 patients who presented with generalized eruptions suspected to be drug-related, including DIHS, Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN), maculopapular exanthema (MPE), erythema multiforme (EM), erythroderma, and toxicoderma. The correlation coefficients between serum TARC levels and clinical parameters in peripheral blood samples were calculated.ResultsSerum TARC levels in patients with DIHS were higher than those found in patients with SJS/TEN, MPE, EM, and toxicoderma. TARC levels had 100% sensitivity and 92.3% specificity in diagnosing DIHS, with a threshold value of 13,900 pg/mL. Serum TARC levels positively correlated with age, white blood cell (WBC) count, neutrophil count, eosinophil count, monocyte count, atypical lymphocyte (Aty-ly) count, serum blood urea nitrogen (BUN) levels, and creatinine (Cr) levels. It negatively correlated with serum total protein (TP), albumin (Alb), and estimated glomerular filtration rate (eGFR). Among these clinical parameters, blood eosinophil counts were most strongly correlated with serum TARC levels, with a correlation coefficient of 0.53.ConclusionsSerum TARC levels are well correlated with blood eosinophil counts in patients with generalized drug eruptions, indicating that Th2-type immune reactions underlie TARC production. Serum TARC measurements also have potent diagnostic value for DIHS, with high sensitivity and specificity
Clinical features of severe malaria: Protective effect of mixed plasmodial malaria
No full textAbstractObjectiveTo investigate clinically severe malaria patients with Plasmodium falciparum (P. falciparum), Plasmodium vivax (P. vivax) and mixed species infections.MethodsThis study was conducted at Dr. Saiful Anwar General Hospital, Malang, Indonesia, from December 2011 to May 2013. Twenty nine patients (mean age of 41 years, 22% female), who suffered from severe malaria according to World Health Organization criteria (major and minor) and other criteria based on previous studies, were selected by consecutive sampling. Blood samples were obtained at admission from peripheral blood for microscopic diagnostic, nested PCR and laboratory examination of blood chemistry. Laboratory results were compared between the groups and correlated to each other.ResultsFrom 29 samples, eight (28%) were diagnosed as P. falciparum mono-infection, 12 (41%) as P. vivax mono-infection and nine (31%) as mixed infections, confirmed by PCR. Cerebral malaria occurred in P. falciparum or mixed species infection only. Parasitaemia was highest in P. falciparum mono-infection. Mean haemoglobin was significantly lower in P. falciparum than P. vivax infection (P = 0.01). Mean thrombocyte count (77138/μL) was low in all groups. Mean urea, creatinine, total and direct bilirubin were significantly higher in P. falciparum mono-infection compared to other groups, whereas aspartate aminotransferase and alanine aminotransferase showed no significant differences. Parasitaemia was positively correlated with an increase in urea, creatinine, bilirubin and leucocytosis in all species.ConclusionsBoth Plasmodium species can solely or in combination cause severe malaria. Mixed infection was generally more benign than P. falciparum mono-infection and seemed to have some protective effects
High resolution sequencing of hepatitis C virus reveals limited intra-hepatic compartmentalization in end-stage liver disease
No full textBackground & AimsThe high replication and mutation rate of hepatitis C virus (HCV) results in a heterogeneous population of viral sequences in vivo. HCV replicates in the liver and infected hepatocytes occur as foci surrounded by uninfected cells that may promote compartmentalization of viral variants. Given recent reports showing interferon stimulated gene (ISG) expression in chronic hepatitis C, we hypothesized that local interferon responses may limit HCV replication and evolution.MethodsTo investigate the spatial influence of liver architecture on viral replication we measured HCV RNA and ISG mRNA from each of the 8 Couinaud segments of the liver from 21 patients undergoing liver transplant.ResultsHCV RNA and ISG mRNA levels were comparable across all sites from an individual liver but showed up to 500-fold difference between patients. Importantly, there was no association between ISG and HCV RNA expression across all sites in the liver or plasma. Deep sequencing of HCV RNA isolated from the 8 hepatic sites from two subjects showed a similar distribution of viral quasispecies across the liver and uniform sequence diversity. Single genome amplification of HCV E1E2-envelope clones from 6 selected patients at 2 hepatic sites supported these data and showed no evidence for HCV compartmentalization.ConclusionsWe found no differences between the hepatic and plasma viral quasispecies in all patients sampled. We conclude that in end-stage liver disease HCV RNA levels and the genetic pool of HCV envelope sequences are indistinguishable between distant sites in the liver and plasma, arguing against viral compartmentalization.Lay summaryHCV is an RNA virus that exists as a quasispecies of closely related genomes that are under continuous selection by host innate and adaptive immune responses and antiviral drug therapy. The primary site of HCV replication is the liver and yet our understanding of the spatial distribution of viral variants within the liver is limited. High resolution sequencing of HCV and monitoring of innate immune responses at multiple sites across the liver identified a uniform pattern of diversity and argues against viral compartmentalization
Adaptación transcultural del cuestionario acerca de la función intestinal (LARS Score) para su aplicación en pacientes operados de cáncer de recto medio y bajo
No full textResumenIntroducciónEl tratamiento en el cáncer de recto ha progresado en la última década. Hoy es factible ofrecer una cirugía con preservación de esfínteres, realizando anastomosis colorrectales bajas o anastomosis coloanales. Esto ha determinado que muchos pacientes desarrollen disfunción intestinal que puede llegar a ser severa, agrupando una serie de alteraciones que se conocen como síndrome de resección anterior baja.ObjetivoEfectuar una adaptación cultural de la versión 1.0 en español neutro del cuestionario acerca de la función intestinal o Low Anterior Resection Syndrome Score (LARS Score), efectuando traducción, comparación de traducciones, traducción inversa y prueba piloto.ResultadosLos resultados obtenidos de la prueba piloto revelan que la población encuestada logró comprender el instrumento, por lo que no se realizaron modificaciones posteriores.ConclusiónSe cuenta con una versión adaptada del cuestionario LARS para ser usada en Chile, la cual puede someterse a procesos de validación y establecer las características psicométricas para ser usada en pacientes con cáncer de recto operados.AbstractIntroductionThe treatment of rectal cancer has progressed in the past decade. Nowadays, it's feasible to provide sphincter sparing surgery with low colorectal anastomosis or coloanal anastomosis. This has determined that many patients develop intestinal dysfunctions that can become severe, grouping a number of disorders known as low anterior resection syndrome.ObjectiveTo perform a cultural adaptation of the version 1.0 questionnaire about bowel function or Low Resection Syndrome Score (LARS Score) in neutral Spanish, making a translation, comparing translations, back translation and pilot test.ResultsThe results of the pilot test showed that the population surveyed understood the instrument, so that no further modifications were made.ConclusionWe now have an adapted version of the LARS questionnaire for use in Chile, which can undergo validation processes to establish the psychometric characteristics for use in patients with rectal cancer surgery
In vitro antimicrobial activities of metabolites from vaginal Lactobacillus strains against Clostridium perfringens isolated from a woman's vagina
No full textAbstractBackgroundMore than 50 different species of bacteria may live in a woman's vagina, with lactobacilli being the predominant microorganism found in healthy adult females. Lactobacilli are relevant as a barrier to infection and are important in the impairment of colonization by pathogens, owing to competitive adherence to adhesion sites in the vaginal epithelium and their capacity to produce antimicrobial compounds.MethodsThe aim of the present study was to demonstrate the inhibitory capability of Lactobacillus metabolites against Clostridium perfringens, an anaerobic Gram-positive bacterium. These bacteria were isolated from vaginal swabs by using culture-dependent approaches, and the bacteriostatic effect of Lactobacillus metabolites, extracted from different isolates, was assessed using a modified E test.ResultsAmong the 100 vaginal swabs, 59 (59%) samples showed the presence of Lactobacillus strains and only one sample contained C. perfringens. Lactobacillus metabolites demonstrated the significant potency of in vitro activity against C. perfringens, with minimal inhibitory concentration values ranging from 15.6 μg/mL to 31.2 μg/mL.ConclusionThis study suggests that women without vaginal Lactobacillus strains may be susceptible to nonindigenous and potentially harmful microorganisms
Sub-subleading soft gravitons: New symmetries of quantum gravity?
No full textAbstractDue to the seminal work of Weinberg, Cachazo and Strominger we know that tree level quantum gravity amplitudes satisfy three factorization constraints. Building on previous works which relate two of these constraints to symmetries of gravity at null infinity, we present strong evidence that the third constraint is also equivalent to a new set of symmetries. Our analysis suggests that the symmetry group of quantum gravity may be richer than the BMS group –or infinite dimensional extension thereof– previously considered
Determination of cadmium and lead in perch fish samples by differential pulse anodic stripping voltammetry and furnace atomic absorption spectrometry
No full textAbstractLead and cadmium contents in the edible parts (muscle, fillet) of 17 commercially used fish species from South Egypt River Nile (Aswan) were determined by means of DPSAV (differential pulse stripping anodic voltammetry). In the sample preparation step, all fish samples were lyophilised, milled in a ball mill and finally decomposed by using mixed acid (HNO3+HClO4). The accuracy of the concentrations determined in this study was checked by the measurements of the certified reference material CRM No. 422, cod muscle from the Commission of the European Communities, Community Bureau of Reference. All Pb2+ and Cd2+ concentrations observed from species of Egypt River Nile showed that fish from this area are a good source of these essential elements and the developed method is accepted as a good analytical routine method for these samples