Microwave pasteurization of apple juice: Modeling the inactivation of Escherichia coli O157:H7 and Salmonella Typhimurium at 80-90 °C.

Although due to their acidity some fruit juices are considered safe, several outbreaks have been reported. For processing fruit juices, microwave heating offers advantages such as shorter come-up time, faster and uniform heating, and energy efficiency. Thus, it could be a beneficial alternative to conventional pasteurization. The objective of this study was to study the inactivation kinetics of Escherichia coli O157:H7 and Salmonella Typhimurium under microwave pasteurization at temperatures between 80 and 90 °C, i.e., at conditions that are employed in conventional pasteurization. Inoculated juices were treated at different power levels (600 W, 720 W) and treatment times (5s, 10s, 15s, 20s, 25s). Time-temperature profiles were obtained by fiber-optic sensors in contact with the samples allowing continuous data collection. The log-logistic and Arrhenius equations were used to account for the influence of the temperature history; thus, resulting in two different modeling approaches that were compared in terms of their prediction abilities. Survival kinetics including non-isothermal conditions were described by a non-linear ordinary differential equation that was numerically solved by the Runge-Kutta method (ode45 in MATLAB ®). The lsqcurvefit function (MATLAB®) was employed to estimate the corresponding survival parameters, which were obtained from freshly made apple juice, whereas the prediction ability of these parameters was evaluated on commercial apple juices. Results indicated that inactivation increased with power level, temperature, and treatment time reaching a microbial reduction up to 7 Log10 cycles. The study is relevant to the food industry because it provides a quantitative tool to predict survival characteristics of pathogens at other non-isothermal processing conditions.

Early outcome of a 31-gene expression profile test in 86 AJCC stage IB-II melanoma patients. A prospective multicentre cohort study.

BACKGROUND: The clinical and pathological features of primary melanoma are not sufficiently sensitive to accurately predict which patients are at a greater risk of relapse. Recently, a 31-gene expression profile (DecisionDx-Melanoma) test has shown promising results. OBJECTIVES: To evaluate the early prognostic performance of a genetic signature in a multicentre prospectively evaluated cohort. METHODS: Inclusion of patients with AJCC stages IB and II conducted between April 2015 and December 2016. All patients were followed up prospectively to assess their risk of relapse. Prognostic performance of this test was evaluated individually and later combined with the AJCC staging system. Prognostic accuracy of disease-free survival was determined using Kaplan-Meier curves and Cox regression analysis. Results of the gene expression profile test were designated as Class 1 (low risk) and Class 2 (high risk). RESULTS: Median follow-up time was 26 months (IQR 22-30). The gene expression profile test was performed with 86 patients; seven had developed metastasis (8.1%) and all of them were in the Class 2 group, representing 21.2% of this group. Gene expression profile was an independent prognostic factor for relapse as indicated by multivariate Cox regression analysis, adjusted for AJCC stages and age. CONCLUSIONS: This prospective multicentre cohort study, performed in a Spanish Caucasian cohort, shows that this 31-gene expression profile test could correctly identify patients at early AJCC stages who are at greater risk of relapse. We believe that gene expression profile in combination with the AJCC staging system could well improve the detection of patients who need intensive surveillance and optimize follow-up strategies.

Soluble Klotho and Brain Atrophy in Alcoholism.

AIM: Fibroblast growth factor (FGF-23) and α-Klotho (Klotho) levels may be altered in inflammatory conditions, possibly as compensatory mechanisms. Klotho exerts a protective effect on neurodegeneration and improves learning and cognition. No data exist about the association of Klotho and FGF-23 levels with brain atrophy observed in alcoholics. The aim of this study is to explore these relationships. SHORT SUMMARY: FGF-23 and Klotho levels are altered in inflammation, possibly as compensatory mechanisms. Klotho enhances learning, but its role in ethanol-mediated brain atrophy is unknown. We found higher FGF-23 and lower Klotho levels in 131 alcoholics compared with 41 controls. Among cirrhotics, Klotho was higher and inversely related to brain atrophy. METHODS: The study was performed on 131 alcoholic patients (54 cirrhotics) and 41 age- and sex-matched controls, in whom a brain computed tomography (CT) was performed and several indices were calculated. RESULTS: Marked brain atrophy was observed among patients when compared with controls. Patients also showed higher FGF-23 and lower Klotho values. However, among cirrhotics, Klotho values were higher. Klotho was inversely related to brain atrophy (for instance, ventricular index (ρ = -0.23, P = 0.008)), especially in cirrhotics. Klotho was also directly related to tumor necrosis factor (TNF) alpha (ρ = 0.22; P = 0.026) and inversely to transforming growth factor (TGF)-ß (ρ = -0.34; P = 0.002), but not to C-reactive protein (CRP) or malondialdehyde levels. FGF-23 was also higher among cirrhotics but showed no association with CT indices. CONCLUSIONS: Klotho showed higher values among cirrhotics, and was inversely related to brain atrophy. FGF-23, although high among patients, especially cirrhotics, did not show any association with brain atrophy. Some inflammatory markers or cytokines, such as CRP or TGF-ß were related to brain atrophy.

Vitamin D, vascular calcification and mortality among alcoholics.

AIMS: To analyze the relationship between low vitamin D levels and mortality among alcoholics. METHODS: One hundred twenty-eight alcoholic patients admitted to our hospital were followed up as outpatients. Nutritional status was evaluated measuring percentages of fat and lean mass in different body compartments. RESULTS: Lower vitamin D levels were observed in patients with worse liver function. Vitamin D was lower in patients with lower total lean mass (Z = 2.8, P = 0.005), but it was not related to fat mass. There was a significant trend to higher long-term mortality among non-cirrhotics with vitamin D levels below 30 ng/ml, although Cox's regression model revealed that only Child score and age were independently related to mortality. CONCLUSION: Vitamin D deficiency is common among alcoholic patients and is associated with low lean mass and liver dysfunction. Among non-cirrhotics, serum vitamin D levels below 30 ng/ml are associated with a greater long-term mortality.

Antioxidant vitamins and brain dysfunction in alcoholics.

AIMS: Alcohol induces cytokine secretion by Kupffer cells, which may exert also deleterious effects on distant organs, mediated in part by cytokine-derived increased production of reactive oxygen species (ROS). It is therefore important to assess antioxidant levels. The objective of this study is to analyse the relation of antioxidant vitamins with brain atrophy and cognitive dysfunction. METHODS: In 77 alcoholic patients admitted for withdrawal syndrome, subjected to brain computed tomography (CT), and 19 controls, we determined antioxidant vitamin levels and analysed their relationships with data of brain atrophy and dysfunction. Searching for causes of altered vitamin levels, we also assessed liver function, nutritional status, eating habits, alcohol intake, proinflammatory cytokine (TNF-α, IL-6, IL-8) levels and malondialdehyde (MDA) levels. RESULTS: Both retinol (vitamin A) and tocopherol (vitamin E) levels were decreased in alcoholics, the former in relation with liver failure, and the latter in relation with triglyceride levels and fat mass. Both were related to data of brain atrophy and cerebellar shrinkage (to which also IL-6 was significantly related). CONCLUSION: Among alcoholics, liver function impairment leads to altered serum vitamin A levels, which are related to brain alterations. Vitamin E levels are also decreased, but although in relation with liver function impairment, its decrease seems to be more dependent on nutritional status and irregular eating habits. Both vitamins are lower in patients with cerebellar atrophy and other features related to brain atrophy.

Palm tree mulch as substrate for primary treatment wetlands processing high strength urban wastewater.

The life span of subsurface flow treatment wetlands is determined by the clogging of the substrate. Thus, the influent should undergo primary treatment to reduce loadings of suspended solids and dissolved organic matter. An-organic based substrate should be less prone to clogging because of its remarkably higher porosity and plasticity. Mulch obtained from branches of the Canarian palm tree (Phoenix canariensis) has been tested as substrate for mixed flow, intermittently fed treatment wetland mesocosms processing high strength urban wastewater. The effect of the presence of plants (Phragmites and Cyperus), influent pressure and hydraulic loading rate was studied. The best removals (SS: 89%, COD: 77%, turbidity: 82%) have been obtained with planted reactors treating highly concentrated influents at the lower hydraulic loading rates tested. The palm tree mulch units achieved similar removals of SS, COD and turbidity to one having gravel as substrate and planted with common reed. Mulch obtained from stems of giant reed (Arundo donax) provided similar removals of SS and turbidity but that of COD was lower. The combination of organic-based TWs with gravel-based ones provided high removals (SS: 95%, COD: 78%, turbidity: 95%) while the risk of clogging was strongly reduced.

Thermoelectric bismuth telluride nanostructures fabricated by electrodeposition within flexible templates.

Bismuth telluride, a highly efficient thermoelectric material, stands out for applications around room temperature in wearable devices. By harnessing the thermal gradient established between the human body and ambient temperature, we can generate useable electricity. Notably, bismuth telluride nanostructures exhibit significantly lower thermal conductivities compared to their bulk counterparts. As a result, the thermoelectric efficiency achieved is notably higher. Our research focuses on developing efficient nanostructured materials based on bismuth telluride inside a flexible substrate made of polyester. We employ scalable methods, such as template-assisted electrochemical deposition, to fabricate these nanostructures. In this study, we present an approach to the development of flexible nanostructured thermoelectric materials. Despite using a reduced quantity of active material, our electrochemically deposited nanostructures inside a flexible template demonstrate a remarkable performance. They exhibit 24 % of the Power Factor reported for conventional electrochemically fabricated Bi2Te3 thin films, and notably, they even surpass the Power Factor reported for flexible Bi2Te3-based inks used in the creation of flexible generators. This achievement underscores the potential of our method in the advancement of efficient, flexible thermoelectric devices.

Utility of transcranial sonography in the diagnosis of drug-induced parkinsonism: a prospective study.

BACKGROUND AND PURPOSE: Drug-induced parkinsonism usually resolves after discontinuation of the causative agent. However, it persists in some patients, who actually have subclinical neurodegenerative parkinsonism. Identification of this condition is important because these patients could benefit from therapeutic measures. The objective of this study was to prove whether transcranial sonography, a technique used in the diagnosis of neurodegenerative parkinsonism, can be used for the said identification. METHODS: In this prospective study, patients with drug-induced parkinsonism were followed for at least 6 months after discontinuation of the causative drug and performance of blinded transcranial sonography. Patients were categorized as having iatrogenic parkinsonism if the clinical presentation had resolved or subclinical drug-exacerbated parkinsonism if it persisted. Once the patient was classified into one of the two groups, an expert assessed the transcranial sonography findings and their agreement with the clinical diagnosis. RESULTS: Twenty patients composed the group for analysis of results. Assessing hyperechogenicity in the substantia nigra >20 mm2 and/or hyperechogenic lentiform nucleus, differences were detected between the iatrogenic parkinsonism and the subclinical drug-exacerbated parkinsonism groups, although they did not reach statistical significance (Fisher's exact test 0.09). Joint assessment of sonographic alterations in both structures had a negative predictive value of 85.7% for diagnosis of drug-induced parkinsonism, with a negative likelihood ratio of 0.3. CONCLUSIONS: Although in our study statistically significant differences were not found between the transcranial sonography characteristics of subclinical drug-exacerbated parkinsonism and iatrogenic parkinsonism patients, we believe that transcranial sonography is a valid technique for diagnosis of drug-induced parkinsonism.

Treatment variability and its relationships to outcomes among patients with Wernicke's encephalopathy: A multicenter retrospective study.

BACKGROUND: Despite guidelines and recommendations, Wernicke's encephalopathy (WE) treatment lacks evidence, leading to clinical practice variability. AIMS: Given the overall lack of information on thiamine use for WE treatment, we analyzed data from a large, well-characterized multicenter sample of patients with WE, examining thiamine dosages; factors associated with the use of different doses, frequencies, and routes; and the influence of differences in thiamine treatment on the outcome. METHODS: This retrospective study was conducted with data from 443 patients from 21 centers obtained from a nationwide registry of the Spanish Society of Internal Medicine (from 2000 to 2012). Discharge codes and Caine criteria were applied for WE diagnosis, and treatment-related (thiamine dosage, frequency, and route of administration) demographic, clinical, and outcome variables were analyzed. RESULTS: We found marked variability in WE treatment and a low rate of high-dose intravenous thiamine administration. Seventy-eight patients out of 373 (20.9%) received > 300mg/day of thiamine as initial dose. Patients fulfilling the Caine criteria or presenting with the classic WE triad more frequently received parenteral treatment. Delayed diagnosis (after 24h hospitalization), the fulfillment of more than two Caine criteria at diagnosis, mental status alterations, and folic acid deficiency were associated significantly with the lack of complete recovery. Malnutrition, reduced consciousness, folic acid deficiency, and the lack of timely thiamine treatment were risk factors for mortality. CONCLUSIONS: Our results clearly show extreme variability in thiamine dosages and routes used in the management of WE. Measures should be implemented to ensure adherence to current guidelines and to correct potential nutritional deficits in patients with alcohol use disorders or other risk factors for WE.

Role of glutathione S-transferases in melanoma susceptibility: association with GSTP1 rs1695 polymorphism.

BACKGROUND: Glutathione S-transferases (GSTs) GSTM1, GSTT1 and GSTP1 are multifunctional enzymes involved in the detoxification of a wide range of reactive oxygen species produced during melanin synthesis and oxidative stress processes. OBJECTIVES: Single nucleotide polymorphisms (SNPs) in GSTP1 and copy number variants in GSTM1 and GSTT1 may be candidate low-penetrance variants with a role in susceptibility to malignant melanoma (MM). METHODS: In this case-control study, 562 Spanish patients with sporadic MM and 338 cancer-free control subjects were included, and the role of polymorphisms in these GST genes was investigated. Genotypes were established by quantitative real-time polymerase chain reaction for GSTM1 and GSTT1 while TaqMan probes were used to genotype GSTP1 SNPs. RESULTS: The GSTP1 polymorphism rs1695, which encodes the amino acid change p.Ile105Val, was individually associated with MM [odds ratio (OR): 1·32, 95% confidence interval (CI): 1·06-1·63]. Furthermore, individuals carrying one or two MC1R nonsynonymous changes and GSTP1 rs1695 rare allele had an increased risk of developing MM (OR: 3·34, 95% CI: 1·42-8·09 and OR: 20·42, 95% CI: 2·80-417·42, respectively). CONCLUSIONS: This is the first time that the GSTP1 rs1695 polymorphism is reported to be associated with MM. In addition, this study is one of the largest GST polymorphism studies undertaken in the Spanish population and the first time that copy number variants have been scrutinized in relation to MM.

High-pressure processing inactivates Listeria innocua yet compromises Queso Fresco crumbling properties.

The objective of this study was to determine the effectiveness of high-pressure processing to inactivate Listeria innocua (a Listeria monocytogenes surrogate) in Queso Fresco, and to study the effects of the high-pressure treatment on cheese-crumbling properties. Queso Fresco was made with pasteurized, homogenized milk, lactic acid bacterial starter culture, chymosin, and flake salt. Cheeses were pressed (0.1 MPa) for 1h before crumbling and inoculation with a cocktail of 3 strains of L. innocua, and then pressed for 12 h (0.1 MPa). High-pressure processing treatments of sliced cheese rounds included pressure from 400 to 600 MPa for 1 to 25 min. Cheese sample temperatures, initially approximately 21°C, increased during pressurization and decreased gradually during the holding time. The highest temperature increase was to 23.6°C at 600 MPa. Greater than 5-log reductions occurred at set-point pressures of 500, 550, or 600 MPa when held for at least 15, 3, or 1 min, respectively. However, because inactivation was neither complete nor permanent and crumbling properties were not maintained under the conditions tested in this study, high-pressure processing is not recommended for Queso Fresco applications.

Alcoholic Liver Disease Among Patients with Wernicke Encephalopathy: A Multicenter Observational Study.

BACKGROUND: data regarding the association between Wernicke encephalopathy (WE) and alcoholic liver disease (ALD) are scarce in spite of alcohol consumption being the main risk factor for WE. AIMS: to describe the frequency of ALD in a cohort of patients diagnosed with WE and alcohol use disorders (AUDs) and to compare the characteristics of WE patients with and without ALD. METHODS: we conducted an observational study in 21 centers through a nationwide registry of the Spanish Society of Internal Medicine. WE Caine criteria were applied and demographic, clinical, and outcome variables were analyzed. RESULTS: 434 patients were included in the study, of which 372 were men (85.7%), and the mean age was 55 ± 11.8 years. ALD was present in 162 (37.3%) patients and we found a higher percentage of cases with tremor, flapping and hallucinations in the ALD group. A total of 22 patients (5.0%) died during admission (7.4% with ALD vs 3.7% without ALD; P = 0.087). Among the ALD patients, a relationship between mortality and the presence of anemia (Odds ratio [OR]=4.6 Confidence interval [CI]95% 1.1-18.8; P = 0.034), low level of consciousness (OR=4.9 CI95% 1.1-21.2; P = 0.031) and previous diagnosis of cancer (OR=10.3 CI95% 1.8-59.5; P = 0.009) was detected. Complete recovery was achieved by 27 patients with ALD (17.8%) and 71 (27.8%) without ALD (P = 0.030). CONCLUSION: the association of WE and ALD in patients with AUDs is frequent and potentially linked to differences in clinical presentation and to poorer prognosis, as compared to alcoholic patients with WE without ALD.

Vitamin D and nutritional status are related to bone fractures in alcoholics.

BACKGROUND: Bone fractures are common in alcoholics. AIMS: To analyse which factors (ethanol consumption; liver function impairment; bone densitometry; hormone changes; nutritional status, and disrupted social links and altered eating habits) are related to bone fractures in 90 alcoholic men admitted to our hospitalization unit because of organic problems. METHODS: Bone homoeostasis-related hormones were measured in patients and age- and sex-matched controls. Whole-body densitometry was performed by a Hologic QDR-2000 (Waltham, MA, USA) densitometer, recording bone mineral density (BMD) and fat and lean mass; nutritional status and liver function were assessed. The presence of prevalent fractures was assessed by anamnesis and chest X-ray film. RESULTS: Forty-nine patients presented at least one fracture. We failed to find differences between patients with and without fractures regarding BMD parameters. Differences regarding fat mass were absent, but lean mass was lower among patients with bone fracture. The presence of fracture was significantly associated with impaired subjective nutritional evaluation (χ² = 5.79, P = 0.016), lower vitamin D levels (Z = 2.98, P = 0.003) and irregular eating habits (χ² = 5.32, P = 0.02). Reduced lean mass and fat mass, and altered eating habits were more prevalent among patients with only rib fractures (n = 36) than in patients with multiple fractures and/or fractures affecting other bones (n = 13). These last were more closely related to decompensated liver disease. Serum vitamin D levels showed a significant relationship with handgrip strength (ρ = 0.26, P = 0.023) and lean mass at different parts of the body, but not with fat mass. By logistic regression analysis, only vitamin D and subjective nutritional evaluation were significantly, independently related with fractures. CONCLUSION: Prevalent fractures are common among heavy alcoholics. Their presence is related more closely to nutritional status, lean mass and vitamin D levels than to BMD. Lean mass is more reduced, nutritional status is more impaired and there is a trend to more altered eating habits among patients with rib fractures, whereas multiple fractures depend more heavily on advanced liver disease.

Neurophysiology training in the Neurology Specialist Education Program in Spain.

INTRODUCTION: The training period in neurophysiology is a substantial part of the Neurology Specialist Program in Spain. The National Neurology Committee (La Comisión Nacional de Neurología (CNN), which is the body reporting to the Ministries of Health and Education, must ensure compliance to the Program. MATERIAL AND METHODS: During the first trimester of 2008, the CNN sent a questionnaire, in which there was a question asking about this training period, to each of the managers of the 69 teaching units accredited for neurology training in Spain, for them to answer. RESULTS: Of the 69 questionnaires issued, 49 were received completed, which was a response rate of 71%. The neurophysiology training period of the neurology specialist program in Spain was carried out in the same hospital in 44 teaching unit (90%): the remaining 5 sent their neurology trainees to 4 different hospitals. The Unit that carried out the neurophysiology training period was incorporated into the Neurology Department in 27 (55%) cases, and the formula was mixed in 3 (6%). A total of 69% of tutors were satisfied with the training, but was 90% in the hospitals where the unit was integrated into Neurology, and was 65% where this relationship did not exist. The neurologists in training were informed about EEG in 49% of education units, performed EMG/ENG 57%, and informed about evoked potentials in 35% after their training period. CONCLUSIONS: Although the level of satisfaction is high, the level of responsibility assumed by the neurologists in training during their rotation into neurophysiology does not appear to comply to the demands laid out in the training program, particularly in these units not integrated into Neurology Departments.

Development of chia seed (Salvia hispanica) mucilage films plasticized with polyol mixtures: Mechanical and barrier properties.

Food packaging is one of the main contributors to the high rates of environmental contamination; therefore, interest has emerged on the use of biopolymers as alternative materials to replace conventional food packaging. Chia seed (Salvia hispanica) is recognized by having a high content of a polysaccharide called mucilage. The aim of this study was to evaluate the feasibility using of chia seed mucilage (CSM) and a polyol mixture containing glycerol and sorbitol for the development of films. CSM films with higher sorbitol content showed superior tensile strength (3.23 N/mm2) and lower water vapor permeability (1.3*10-9 g/m*s*Pa), but had poor flexibility compared to other treatments. Conversely, high glycerol content showed high elongation at break (67.55%) and solubility (22.75%), but poor water vapor permeability and tensile strength. Film formulations were optimized implementing a factorial design according to response surface methodology. Raman spectra analysis showed shifts from 854 to 872 cm-1 and 1061 to 1076 cm-1, ß (CCO) modes, indicating an increase in hydrogen bonding, responsible for the high tensile strength and decreased water vapor permeability observed in this study. The optimum conditions of polyol concentration were 1.3 g of glycerol and 2.0 g of sorbitol per g of CSM. Based on these results, chia seed mucilage can successfully be used to develop biofilms with potential to be used in drug delivery and edible food coating applications.

The effects of microstructure, Nb content and secondary Ruddlesden-Popper phase on thermoelectric properties in perovskite CaMn1-x Nb x O3 (x = 0-0.10) thin films.

CaMn1-x Nb x O3 (x = 0, 0.5, 0.6, 0.7 and 0.10) thin films have been grown by a two-step sputtering/annealing method. First, rock-salt-structured (Ca,Mn1-x ,Nb x )O thin films were deposited on 11̄00 sapphire using reactive RF magnetron co-sputtering from elemental targets of Ca, Mn and Nb. The CaMn1-x Nb x O3 films were then obtained by thermally induced phase transformation from rock-salt-structured (Ca,Mn1-x Nb x )O to orthorhombic during post-deposition annealing at 700 °C for 3 h in oxygen flow. The X-ray diffraction patterns of pure CaMnO3 showed mixed orientation, while Nb-containing films were epitaxially grown in [101] out of-plane-direction. Scanning transmission electron microscopy showed a Ruddlesden-Popper (R-P) secondary phase in the films, which results in reduction of the electrical and thermal conductivity of CaMn1-x Nb x O3. The electrical resistivity and Seebeck coefficient of the pure CaMnO3 film were measured to 2.7 Ω cm and -270 µV K-1 at room temperature, respectively. The electrical resistivity and Seebeck coefficient were reduced by alloying with Nb and was measured to 0.09 Ω cm and -145 µV K-1 for x = 0.05. Yielding a power factor of 21.5 µW K-2 m-1 near room temperature, nearly eight times higher than for pure CaMnO3 (2.8 µW K-2 m-1). The power factors for alloyed samples are low compared to other studies on phase-pure material. This is due to high electrical resistivity originating from the secondary R-P phase. The thermal conductivity of the CaMn1-x Nb x O3 films is low for all samples and is the lowest for x = 0.07 and 0.10, determined to 1.6 W m-1 K-1. The low thermal conductivity is attributed to grain boundary scattering and the secondary R-P phase.

[Suspected child abuse in paediatric emergency service]. / Sospecha de maltrato infantil en urgencias pediátricas.

OBJECTIVE: To describe the epidemiology of child abuse in an emergency department of a tertiary paediatric hospital. METHODS: Descriptive and retrospective study from January 2008 to January 2006 including patients less than sixteen years of age who were suspected of being abused during the examination in the emergency department. RESULTS: Child maltreatment was 0.07% of all paediatric emergencies (45% physical abuse, 35% sexual abuse and 20% neglect). Mean age of 6 years old, with no gender differences. 86% were suspected of maltreatment. An adult living with the child was suspected in 67% of cases. Social and judicial procedures were activated. A total of 24 children were admitted, 14 under medical criteria and the rest in order to protect the child; 2 had serious neurological consequences and one died. Eight patients were discharged to social service care centres. CONCLUSIONS: We believe it is necessary to improve the pediatrician's knowledge of child abuse and to create specialized units.

Enhanced thermoelectric properties of lightly Nb doped SrTiO3 thin films.

Novel thermoelectric materials developed for operation at room temperature must have similar or better performance along with being as ecofriendly as those commercially used, e.g., Bi2Te3, in terms of their toxicity and cost. In this work, we present an in-depth study of the thermoelectric properties of epitaxial Nb-doped strontium titanate (SrTi1-x Nb x O3) thin films as a function of (i) doping concentration, (ii) film thickness and (iii) substrate type. The excellent crystal quality was confirmed by high resolution transmission electron microscopy and X-ray diffraction analysis. The thermoelectric properties were measured by the three-omega method (thermal conductivity) and van der Pauw method (electrical resistivity), complemented by Seebeck coefficient measurements. A maximum power factor of 8.9 × 10-3 W m-1 K-2 and a thermoelectric figure of merit of 0.49 were measured at room temperature in 50 nm-thick films grown on lanthanum strontium aluminate. The mechanisms behind this high figure of merit are discussed in terms of a possible two-dimensional electron gas, increase of the effective mass of the electrons, electron filtering and change in strain due to different substrates. The overall enhancement of the thermoelectric properties suggests that SrTi1-x Nb x O3 is a very promising n-type candidate for room- to high-temperature applications.

Handgrip strength and lean mass are independently related to brain atrophy among alcoholics.

BACKGROUND: In neurodegenerative disorders or in normal aging humans a relationship between muscle mass and/or performance and brain volume was observed, that is not dependent on age or other confounding factors. The aim of the present study is to analyse the relationship between lean mass and handgrip strength in alcoholics, who frequently show brain and muscle atrophy. METHODS: It was included 101 male patients aged 58.35 ± 11.59 years, and 44 controls, all of them workers of our hospital, drinkers of less than 20 g ethanol/day, of similar age. Patients and controls underwent dominant handgrip assessment with a Collins' dynamometer, whole body composition analysis by densitometry, and brain computed tomography (CT) examination, with further calculation of several indices indicative of brain atrophy. MAIN RESULTS: 1) Brain atrophy is a very common finding among alcoholics, both among cirrhotics and non-cirrhotics. 2) Alcoholics show a marked reduction in handgrip strength, and also in lean mass, especially at the arms and legs -but not in the trunk, even if patients with ascites were excluded.3) There is a relationship between reduced lean mass and brain atrophy, and a close correlation between handgrip strength and brain atrophy, that is independent of age and liver function. 4) Total fat amount is not different among alcoholics and controls, but there are marked differences in fat distribution: alcoholics show less fat in arms, but more fat in trunk, so that if we calculate the peripheral fat/trunk fat index, marked differences were observed among alcoholics and controls. Neither total fat nor fat distribution were related to brain atrophy. CONCLUSION: among alcoholics, as in other neurodegenerative conditions, there is a relationship between reduced lean mass and brain atrophy, and a close correlation between handgrip strength and brain atrophy, that is independent of age, duration of ethanol consumption and liver function.

Prognostic value of serum selenium levels in alcoholics.

In alcoholics, exposure of Kupffer cells to intestinal-borne Gram-negative bacteria increases free radical release, which may, in turn, enhance cytokine secretion, creating a positive feedback loop, which contributes to liver inflammation. Impaired antioxidant mechanisms further aggravates this scenario. Some trace elements, such as selenium, are main cofactors of antioxidant enzymes. Some authors have found low Se levels in alcoholics in relation either with undernutrition, liver dysfunction, or intensity of alcoholism, but in general, Se supplementation has no effect on survival. In this study we measured serum Se in 16 controls and 76 alcoholics, 34 of them cirrhotics, 68 of whom were followed up for a median period of 38 months; 17 died during this period. Se levels were lower in patients than in controls and were related to prothrombin activity and nutritional status, more closely to this last parameter (stepwise logistic regression analysis). Patients who died showed lower Se values than those who survived. Se values over the median were associated with better survival, assessed by Kaplan-Meier curves and log-rank test. However, in multivariate analysis (Cox regression model), prothrombin activity displaced serum Se as a prognostic factor. We conclude that serum Se levels are low in alcoholics; these low values depend more heavily on impaired nutrition but also on liver dysfunction; although low Se levels were associated with a higher mortality, prothrombin activity displaced serum Se when survival was assessed using Cox's regression model.