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The freeze-drying technique is employed for the production of novel strontium bromide/graphite/nanocellulose composites for thermochemical heat storage application. The aim is to obtain a better control and stability of salt organization within the composite, while maximizing the air/salt and salt/graphite interfacial areas and enhancing mass and heat transfer associated to the salt hydration and dehydration. A comparison with a conventional wet impregnation method is also reported. The morphology was investigated by means of scanning electron microscopy. Differential scanning calorimetry was employed to evaluate the energy storage density, while hydration kinetics were evaluated at 23 °C and 50% RH. The wet impregnation approach delivered materials with a limited porosity while freeze-drying produced highly porous structures with oriented channels for moisture transport across the composite. The organic binder provided an active contribution to the energy storage process, producing energy storage densities up to 764 kJ/kg, 48% greater than the theoretical value. Freeze-dried nanocellulose composites evidenced a significant increase of 54% in the hydration kinetics, compared to the pristine salt. Based on these results, the freeze-drying of ternary composites based on salt hydrate, graphite and nanocellulose is envisaged as a promising route for the production of fast charge and discharge thermochemical storage systems.

Some evidence about the role of the androgen receptor (AR) in pathogenesis of glioblastoma have been reported, but no study has focused on measuring the activity of the AR in GB. Therefore, the aim of this work is to study the role of AR and its activity as prognostic biomarkers in glioblastoma (GB).Molecular and clinical data from The Cancer Genome Atlas database were used. The AR-expression at protein-level was obtained from reversed phase protein array (RPPA) assays. The AR-activity was determined by calculating the AR-score, an index calculated by using the expression (at RNA-level) of 13 androgen-responsive-genes. Univariate and multivariate Cox-regression analyses were performed. Finally, a correlation analysis was conducted between protein expression data and the AR-score.Two-hundred and thirty-three patients were included. RPPA data showed a mean AR abundance of 0.027(Statistical Deviation = 0.38) in GB. The univariate Cox-regression analysis showed that the AR-Score was associated with a worse prognosis (Hazard Ratio (HR) = 1.070) while the AR-expression did not show any relationship with survival (HR = 0.869). The association of the AR-score with worse overall survival (OS) was still significant in the multivariate analysis (HR = 1.054). The highest correlation coefficients between the AR-score and RPPA were identified in a group of proteins involved in apoptotic process regulation.GB patients with a high AR-activity present a worse prognosis in terms of OS. Thus, the activity of the AR may have a pathogenic role in GB. In this regard, the activation of the AR in GB may be associated with a dysregulation of apoptosis.

BackgroundBrain-derived neurotrophic factor (BDNF) is involved in neurogenesis and in the protection against oxidative damage and neuronal apoptosis. After exercise, there is an increased expression of this myokine, especially in skeletal muscle and brain. Low BDNF levels have been described in neurodegenerative diseases. Alcoholics show both muscle atrophy and brain atrophy. Thus, this study was performed in order to analyze serum BDNF levels among alcoholics and their associations with brain atrophy and muscle strength.MethodsSerum BDNF values were determined to 82 male alcoholics and 27 age-matched controls, and compared with handgrip strength, with the presence of brain atrophy, assessed by computed tomography, and with the intensity of alcoholism and liver function derangement.ResultsBDNF levels and handgrip strength were significantly lower among patients. Handgrip strength was correlated with BDNF values, both in the whole population and in alcoholics, especially in patients over 59 years of age. BDNF was poorly related to liver dysfunction but showed no relationship with brain atrophy or age.ConclusionChronic alcoholics show decreased BDNF serum levels that are related to muscle function impairment rather than to age, brain atrophy, liver dysfunction, or the amount of ethanol consumed.

Here we investigate the relationship between thermomechanical properties and chemical structure of well-characterized lignin-based epoxy resins. For this purpose, technical lignins from eucalyptus and spruce, obtained from the Kraft process, were used. The choice of lignins was based on the expected differences in molecular structure. The lignins were then refined by solvent fractionation, and three fractions with comparable molecular weights were selected to reduce effects of molar mass on the properties of the final thermoset resins. Consequently, any differences in thermomechanical properties are expected to correlate with molecular structure differences between the lignins. Oxirane moieties were selectively introduced to the refined fractions, and the resulting lignin epoxides were subsequently cross-linked with two commercially available polyether diamines (Mn = 2000 and 400) to obtain lignin-based epoxy resins. Molecular-scale characterization of the refined lignins and their derivatives were performed by 31P NMR, 2D-NMR, and DSC methods to obtain the detailed chemical structure of original and derivatized lignins. The thermosets were studied by DSC, DMA, and tensile tests and demonstrated diverse thermomechanical properties attributed to structural components in lignin and selected amine cross-linker. An epoxy resin with a lignin content of 66% showed a Tg of 79 °C from DMA, Young's modulus of 1.7 GPa, tensile strength of 66 MPa, and strain to failure of 8%. The effect of molecular lignin structure on thermomechanical properties was analyzed, finding significant differences between the rigid guaiacyl units in spruce lignin compared with sinapyl units in eucalyptus lignin. The methodology points toward rational design of molecularly tailored lignin-based thermosets.

Amylin is a pancreatic hormone that participates in glucose homeostasis. We aimed to investigate how serum amylin levels are expressed in patients with systemic lupus erythematosus (SLE) compared to matched controls, and their possible relationship to disease-related characteristics, such as activity or damage.144 SLE patients and 96 non-diabetic sex- (female 96% vs. 91%, p=0.43) and age-matched controls (49±11 vs. 51±8 years, p=0.09) were included. Amylin, insulin and C-peptide serum levels, as well as insulin resistance indexes were assessed in both groups. Multivariable regression analysis was performed to compare amylin between groups and to explore its interrelations with SLE features. The analyses were adjusted for glucocorticoids intake and for insulin resistance classic risk factors.Patients with SLE exhibited significant higher serum levels of amylin when compared to controls after multivariable analysis (beta coef. 1.56 [95%CI 1.01-2.11], p=0.000). Moreover, SLE patients not on prednisone (beat coef. 1.54 [95%CI 0.98-2.10] ng/ml, p=0.000) and those on prednisone (beta coef. 1.51 [95%CI 0.96-2.07] ng/ml, p=0.000) disclosed higher amylin serum levels compared to controls in the fully multivariable analysis. Hyperamylinaemia in SLE patients remained significant even adjusting for differences in the insulin resistance and beta cell production rates between patients and controls. The damage produced by the disease and its severity were independently and positively associated with amylin serum levels.Amylin is upregulated in SLE patients compared to controls, regardless of the insulin resistance that SLE may present. The damage produced by the disease and its severity independently explains this upregulation.

Objectives To investigate how markers of beta-cell secretion (proinsulin-processing metabolites) are expressed in SLE patients and their potential relation to features associated with the disease such as activity or damage. Methods One hundred and forty-four SLE patients and 69 nondiabetic sex- and age-matched controls were assessed. Beta-cell secretion molecules, as measured by insulin, split and intact proinsulins, and C-peptide levels were analysed in both groups. Multiple regression analysis was performed to compare proinsulin propeptides between groups and to explore the interrelations with SLE features. Analyses were adjusted for glucocorticoid intake and for insulin resistance classic risk factors. Results Fully multivariable analysis demonstrated that regardless of glucocorticoid use, SLE patients exhibited higher levels of split proinsulin. Likewise, the split proinsulin-to-insulin ratio was upregulated in patients with SLE undergoing glucocorticoid therapy [beta coeficient 0.19 (95% Confidence Interval 0.07, 0.30), P = 0.002] or not [beta coef. 0.09 (95% CI: 0.01, 0.17), P = 0.025]. Similar results were found for the intact proinsulin-to-insulin ratio, although differences were only statistically significant for patients taking glucocorticoids [beta coef. 0.08 (95% CI: 0.03, 0.12), P = 0.001]. SLE damage score was associated with higher serum levels of intact [beta coef. 0.51 (95% CI 0.17, 0.86) pmol/l, P = 0.004] and split proinsulins [beta coef. 1.65 (95% CI 0.24, 3.06) pmol/l, P = 0.022] after multivariable analysis, including disease duration and prednisone use. Conclusion Among patients with SLE, proinsulin-processing metabolites, a marker of beta-cell disruption, are upregulated compared with matched controls. This disproportionate hyperproinsulinemia can be explained by the damage produced by the disease and occurs independently of prednisone use.

Development of surface-engineering strategies, which are facile, versatile, and mild, are highly desirable in tailor-made functionalization of high-performance bioinspired nanocomposites. We herein disclose for the first time a general organocatalytic strategy for the functionalization and hydrophobization of nacre-mimetic nanocomposites, which includes vide supra key aspects of surface engineering. The merging of metal-free catalysis and the design of nacre-mimetic nanocomposite materials were demonstrated by the organocatalytic surface engineering of cellulose nanofibrils/clay nanocomposites providing the corresponding bioinspired nanocomposites with good mechanical properties, hydrophobicity, and useful thia-, amino, and olefinic functionalities.

This study sought to identify the clinical and demographic correlates of offenders with a violent instant offense as well as those with a history of greater criminal recidivism among a sample of county jail inmates with a substance use disorder. Clinical, demographic, and arrest data from 176 male inmates (76.0% Caucasian) incarcerated in a county jail facility were utilized to address the present study’s objectives. All inmates were repeat offenders and met Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV; American Psychiatric Association [APA], 1994) diagnostic criteria for dependence on one or more substances based on a structured clinical interview. Clinical variables included patterns and prevalence of various DSM-IV substance-specific dependence diagnoses (i.e., alcohol, cannabis, cocaine, and heroin), as well as several non-substance use disorder psychiatric diagnoses (e.g., posttraumatic stress disorder [PTSD], antisocial personality disorder). Demographic variables included age, race, marital status, employment status, educational attainment, and estimated annual income level. Inmates with a violent instant offense had a higher prevalence of PTSD, antisocial personality disorder, and both major depressive and manic episodes relative to non-violent offenders. The only significant associations between number of prior bookings and all the studied clinical and demographic variables involved the presence of a PTSD diagnosis and income level. Co-occurring psychiatric disorders are prevalent among substance-dependent violent offenders, while very few of the studied variables appear significantly related to the frequency of prior criminal behavior. Research implications and clinical implications for county jail classification procedures are discussed.

Nacre-inspired clay nanocomposites have excellent mechanical properties, combined with optical transmittance, gas barrier properties, and fire retardancy, but the mechanical properties are still be ...

Foam-like clay-nanocellulose hybrids are of great interest as load-bearing structural foams with excellent fire retardancy, due to unique effects from clay on thermal cellulose degradation. For the ...

A new type of high reinforcement content clay–cellulose–thermoset nanocomposite is proposed, where epoxy precursors diffuse into a wet porous clay–nanocellulose mat, followed by curing. The processing concept was scaled to >200 μm thickness composites, the mechanical properties were high for nanocomposites, and the materials showed better tensile properties at 90% RH compared with typical nanocellulose materials. The nanostructure and phase distributions were studied using transmission electron microscopy; Young’s modulus, yield strength, ultimate strength, and ductility were determined as well as moisture sorption, fire retardancy, and oxygen barrier properties. Clay and cellulose contents were varied as well as the epoxy content. Epoxy had favorable effects on moisture stability and also improved reinforcement effects at low reinforcement content. A more homogeneous nano- and mesoscale epoxy distribution is still required for further property improvements. The materials constitute a new type of three-ph...

CNFs (cellulose nanofibers) based on holocellulose have a pure cellulose fibril core, with a hemicellulose coating. The diameter is only around 6–8 nm and the hemicellulose surface coating has anio ...

Nanostructured materials are difficult to prepare rapidly and at large scale. Melt-processed polymer-clay nanocomposites are an exception, but the clay content is typically below 5 wt%. An approach ...

Clay aerogels are foam-like materials with potential to combine high mechanical performance with fire retardancy. However, the compression strength of these aerogels is much lower than theoretically predicted values. High-strength aerogels with more than 95% porosity were prepared from a ternary material system based on poly(vinyl alcohol), montmorillonite clay platelets, and cellulose nanofibrils. A hydrocolloidal suspension of the three components was subjected to freeze-drying so that a low-density aerogel foam was formed. Cell structure was studied by field-emission scanning electron microscopy. Interactions at the molecular scale were observed by X-ray diffraction and Fourier transform infrared spectroscopy. Cross-linking was carried out using glutaraldehyde or borax, and moisture stability was investigated. These biobased ternary aerogels showed compression strength much better than that of previously studied materials and also showed strength higher than that of high-performance sandwich foam cores such as cross-linked polyvinyl chloride foams.

Currently, aerogel materials have drawn great attention due to their excellent porous structure. To further enhance their mechanical and electrical properties, nanostructured carbon materials such as carbon nanotubes and graphene have been applied to form various composites. In this work, we have employed a facile method to synthesize PEDOT:PSS conducting polymer aerogels embedded with carbon nanotubes. These aerogels are prepared using iron (III) chloride hexahydrate as crosslinkers. Surface morphology, pore properties, compression strength and electrochemical performance of the aerogel composites are evaluated. The effects of carbon nanotubes on aerogel morphology and their electrochemical performance are also investigated. It is found that the increase of CNTs content brings an improved electrochemical performance in term of a specific capacitance of 35 F g−1 and a cycling stability over 1000 cycles.

In solid foams, most physical properties are determined by the pore size and shape distributions and the organisation of the pores. For this reason, it is important to control the structure of porous materials. We recently tackled this issue with the help of microfluidic-aided foam templating, which allowed us to generate monodisperse and highly ordered chitosan foams. However, the properties of foams also depend on the properties of the pore wall constituents. In case of chitosan-based foams, the foams have poor absolute mechanical properties, simply due to the fact that the solubility of chitosan in water is very low, so that the relative density of the freeze-dried foams becomes very small. Drawing inspiration from the field of nanocomposites, we incorporated cellulose nanofibres into the foamed chitosan solutions, with a view to strengthening the pore walls in the foam and thus the mechanical properties of the final foam. We report here how the cellulose nanofibres affect the structure of both the liquid foam template and the solid foam. The resulting nanocomposite foams have improved mechanical properties, which, however, are not proportional to the amount of cellulose nanofibres in the composites. One reason for this observation is the disturbance of the porous structure of the solid foams by the cellulose nanofibres.

Wood is one of the most sustainable, esthetically pleasing and environmentally benign engineering materials, and is often used in structures found in buildings. Unfortunately, the fire hazards related to wood are limiting its application. The use of transparent cellulose nanofiber (CNF)/clay nanocomposites, with unique brick-and-mortar structure, is proposed as a sustainable and efficient fire protection coating for wood. Fire performance was assessed by cone calorimetry. When exposed to the typical 35 kW/m2 heat flux of developing fires, the time to ignition of coated wood samples increased up to about 4 1/2 min, while the maximum average rate of heat emission (MARHE) was decreased by 46% thus significantly reducing the potential fire threat from wood structures. Keywords: Nanocomposite, Cellulose, Nanofiber, Fire retardant, Cone calorimetry

Objective To assess outcomes after auxiliary nurses were trained and given resources to use active management of the third stage of labor (AMTSL) for all women giving birth in a low-resource, low-risk, rural, public birth center setting in northern rural Honduras. Methods Auxiliary nurses received training on estimation of blood loss before the preintervention phase of the study (July 2004 through April 2005) and AMTSL, including use of intramuscular oxytocin, and estimation of blood loss prior to the intervention phase (July 2007 through June 2008). Preintervention and intervention data on use of oxytocin, blood loss postpartum, hemorrhage rates, and management interventions were collected and compared. Results After nurses received training on AMTSL using intramuscular oxytocin, the use of intramuscular oxytocin during the third stage of labor increased from 63.8% to 96.5%. Postpartum hemorrhage rates decreased from 14.8% to 5.9% (P = 0.001). Use of intrapartum oxytocin, which can have adverse effects, also increased: from 6.1% to 22.7% (P Conclusion Training auxiliary nurses to perform AMTSL using oxytocin in this birth center setting was effective in reducing the rate of postpartum hemorrhage; however, increased use of intrapartum oxytocin may be an unintended outcome of the increased accessibility of oxytocin.

Objetivo: evaluar los cambios en la perdida estimada de sangre y tasas de Hemorragia Posparto [HPP] derivados del entrenamiento en el Manejo Activo de la Tercera Etapa del Parto [MATED] en cinco Clinicas Materno Infantiles del departamento de Yoro, Honduras. Metodologia: durante nueve meses, el equipo de investigacion ensena las habilidades sobre la perdida estimada de sangre, establece una tasa base para la HPP y ensena el manejo activo de la tercera etapa del parto. En cada nacimiento se registran la perdida estimada de sangre, los resultados para la madre y el neonato, asi como el uso calculado de Oxitocina en el periodo posnatal. Los datos obtenidos se analizan estadisticamente con SPSS descriptivo, prueba-T y Chi-cuadrado. Resultados: el periodo de estudio previo al entrenamiento en MATEP incluye 178 casos, el periodo posterior al entrenamiento incluye 392 casos. La perdida estimada de sangre durante el periodo previo es de 109 ml en promedio, comparado con 81 ml en promedio que se obtiene durante el periodo posterior al entrenamiento (p=.004). En la fase previa y posterior a/ entrenamiento, el uso de Oxitocina en el periodo posparto es de 99.5%, aunque en el 17% de los casos reportados la administracion de Oxitocina se realiza despues de la expulsion de la placenta. Despues del entrenamiento en MATER la tasa de hemorragia posparto disminuye del 7.3% al 3.8%, dato que no es estadisticamente significativo.

Postpartum hemorrhage (PPH) is the leading cause of maternal mortality globally. Safe Motherhood policies have been directed towards the reduction of PPH by recommending active management of third-stage labor as the standard of care. One component of active management involves routine use of a uterotonic agent within 1 minute of the delivery of the baby. A case study at Clinica Materno-Infantil, a free-standing public birth center in Honduras, is presented, focusing on methods to reduce PPH. The nursing staff was trained to estimate blood loss and in methods to manage PPH, including elements of active management of the third stage of labor. Medical records were reviewed and an analysis of PPH management compared to estimated blood loss (EBL) was conducted. There was no significant correlation between PPH management techniques and EBL (r = .060; P = .368). There was a statistically significant (P < .001) correlation between oxytocin administration and lower EBL (r = -.232), indicating that there was less blood loss when oxytocin was administered. At Clinica Materno-Infantil, routine use of a uterotonic agent appears beneficial and further implementation of active management of the third stage of labor appears warranted.

Objectives It has been suggested that resistance to insulin action is a feature that accompanies rheumatoid arthritis (RA), a disease where chronic inflammation predominates and classical triggers for insulin resistance (IR) like obesity and diabetes are absents. However, data regarding characterization of RA features associated with this insulin resistance (IR) are lacking. The aim of this study was to investigate how sensitivity to insulin and markers of beta cell dysfunction (proinsulin processing metabolites) are expressed in RA. Methods 101 non-diabetic RA patients and 99 non-diabetic sex and age-matched controls were included in this study. Insulin sensitivity function through homeostatic model assessment (HOMA2), and beta cell secretion through insulin, split and intact proinsulin, and C-peptide were assessed in both groups. We performed multiple regression analysis to compare IR between groups and to explore the relation between RA features and IR. Data were adjusted for glucocorticoids intake and for IR classical risk factors. Results RA patients compared to controls show higher HOMA-IR ( log HOMA-IR, beta coefficient, 0.40 [95% CI 0.20-0.59], p=0.00). When this data was adjusted for glucocorticoids intake, non-on corticosteroid patients maintained a higher IR index (beta coef. 0.14 [95% CI 0.05-0.24], p=0.00). Current prednisone treatment was not associated with higher IR in the patients’ intragroup comparison (beta coef. 0.56 [1.13-1.19], p=0.22). Insulin processing signaling in RA patients showed impaired features via an elevated intact proinsulin levels (beta coef. 3.13 [0.81-5.44] pMol/L, p=0.03 for the comparison between patients and controls). Split proinsulin levels were also higher in RA patients (beta coef. 13.7 pmol/L [3.57-9.40], p=0.00) even adjusting for prednisone intake (beta coef. 2.66 pmol/L [95%CI 1.62-5.95] for non steroids RA patients when compared to controls). In multiple regression analysis, RA features (disease duration, rheumatoid factor, erythrocyte sedimentation rate, C-reactive protein, disease activity through HAQ and DAS28 scores, and current non-biologic disease modifying antirheumatic drug), when adjusted for sex, age and body mass index, were not associated with IR or insulin propeptides. Conclusions Beta cell signaling is impaired in non-diabetic and non-corticoids RA patients. Disclosure of Interest None Declared

Objectives The retinol binding protein 4 (RBP4) has recently been described as a protein highly related with insulin resistance (IR) states like obesity and diabetes. The chronic inflammatory states, like in rheumatoid arthritis (RA), are linked also to insulin resistance by mechanisms that are unknown. Therefore, RA is considered as an insulin resistance model related with a chronic inflammatory state, where diabetes and obesity, classical factors for IR, are absent. The objective of this study is to estimate RBP4 expression in RA patients. Methods 101 RA patients and 115 age and sex-matched controls were included. Pancreatic beta cell function was estimated by classical insulinresistance indexes like HOMA (homeostatic model assessment 2). RBP4, C peptide and insuline levels were measured in patients and controls by a specific enzyme-linked immunosorbent assay (ELISA). Multivariate analysis was performed to compare results between patients and controls and the data were adjusted for glucocorticoids intake and for IR classical risk factors. Results RBP4 levels did not show differences between controls and patients, after adjusting for sex, age, body mass index (BMI) and waist circumference (lnRBP4 2,83 mcg/dl in patients vs. 2,70 mcg/dl, p=0,33). On going steroids patients showed higher RBP4 levels (lnRBP4 3,03 vs 2,61 mcg/dl, p=0.00), after adjusting for age, sex, BMI and waist circumference. Similarly, in the univariate analysis, RBP4 levels tended to correlate with steroid average dose (r=0,20, p=0,14). In our serie, RBP4 levels were not related with the classical IR characteristics, like abdominal waist and BMI, both in controls and patients. Nor these levels showed relation with ESR, CRP, insuline levels or disease activity indexes. Conclusions The molecular mechanisms that lead to IR in RA patients appear to be different from those that ocurr in obesity and diabetes status. RBP4 does not seem to play a role in IR in patients with RA. Disclosure of Interest None Declared

Introduction To investigate how markers of β-cell secretion (proinsulin-processing metabolites) are expressed in rheumatoid arthritis (RA) patients and their potential relation with the insulin resistance (IR) observed in these patients. Methods The 101 RA patients and 99 nondiabetic sex- and age-matched controls were included. IR by homeostatic model assessment (HOMA2), and β-cell secretion, as measured by insulin, split and intact proinsulin, and C-peptide levels were determined for both groups. Multiple regression analysis was performed to compare IR between groups and to explore the interrelations between RA features, proinsulin metabolites, and IR. Data were adjusted for glucocorticoids intake and for IR classic risk factors. Results Compared with controls, RA patients showed higher HOMA-IR (β coef., 0.40 (95% CI, 0.20 to 0.59); P = 0.00). When data were adjusted for glucocorticoids intake, noncorticosteroid patients maintained a higher IR index (β, 0.14 (0.05 to 0.24); P = 0.00). Impaired insulin processing in RA patients was detected by the onset of elevated split proinsulin levels (β, 0.70 pmol/L (0.38 to 1.02); P = 0.00). These data remained significant also when adjusted for prednisone intake (β, 0.19 (0.00 to 0.36) pmol/L; P = 0.04). Split proinsulin-to-C-peptide ratios were higher in RA patients undergoing corticosteroid therapy (β, 0.25 (0.12 to 0.38); P = 0.03) and were nearly significant in comparison between noncorticosteroids patients and controls (β, 0.16 (-0.02 to 0.34); P = 0.08). Interestingly, the impact of HOMA-IR on the ratio of intact proinsulin to C-peptide was higher in controls compared with patients (β, 6.23 (1.41 to 11.06) versus 0.43 (-0.86 to 1.71); P = 0.03). Conclusions β-Cell function is impaired in nondiabetic and in RA patients not taking corticoids by a mechanism that seems to be, at least in part, independent of IR.