Quantum chemistry and kinetics of hydrogen sulphide oxidation.

A fundamental understanding of the acid gas (H2S and CO2) chemistry is key to efficiently implement the desulphurisation process and even the production of clean fuels such as hydrogen or syngas. In this work, we developed a new kinetic model for the pyrolysis and oxidation of hydrogen sulphide by merging two previously reported models with the goal of covering a wider range of conditions and including the effect of carbon dioxide. The resulting model, which consists of 75 species and 514 reactions, was used to conduct rate of production and sensitivity analysis in plug flow reactor simulations, and the results were used to determine the most prominent reactions in which hydrogen sulphide, molecular hydrogen, and sulphur monoxide are involved. The resulting list of important reactions was screened and the kinetics of three of them, i.e., SO2 + S2 → S2O + SO, S2O + S2 → S3 + SO, and SO + SH → S2 + OH, was found to warrant further investigation. With the goal of improving the accurancy of our new kinetic model, we carried out a robust quantum chemistry and Rice-Ramsperger-Kassel-Marcus master equation study to obtain, for the first time, the forward and reverse rate constants for those three reactions at temperatures and pressures of interest for combustion and atmospheric chemistry. This work is the first step of a kinetic study that is aimed at improving the understanding of the chemistry of the pyrolysis and oxidation of H2S, highlighting the importance of sulphur-sulphur interactions and providing a fundamental basis for future kinetic models of H2S not only in the field of combustion, but also in atmospheric chemistry.

A case-control study to differentiate parents' personality traits on anorexia nervosa and affective disorders.

Eating disorders (ED) and affective disorders (AD) in adolescent population and several investigations have pointed out that specific family dynamics play a major role in the onset, course, and maintenance of both disorders. The aim of this study was to extend the literature of this topic by exploring differences between parents' personality traits, coping strategies, and expressed emotion comparing groups of adolescents with different mental conditions (anorexia nervosa vs. affective disorder vs. control group) with a case-control study design. A total of 50 mothers and 50 fathers of 50 girls with anorexia nervosa (AN), 40 mothers and 40 fathers of 40 girls with affective disorder (AD), and 50 mothers and 50 fathers of 50 girls with no pathology that conformed the control group (CG) were measured with the Temperament and Character Inventory (TCI), the COPE Inventory, the Family Questionnaire (FQ), and psychopathology variables, anxiety, and depression. Both parents of girls with AN showed a significant difference in personality, coping strategies, and expressed emotion compared to both parents in the CG, while they presented more similarities to parents of girls in the AD group. Identifying personality traits, expressed emotion, coping strategies, and psychopathology of parents and their daughters will allow improvements in the interventions with the adolescents, parents, and families.

Going deeper into eating and body image pathology in males: Prevalence of muscle dysmorphia and eating disorders in a university representative sample.

Disorders associated with body dissatisfaction such eating disorders (ED) and muscle dysmorphia (MD) in males are understudied and surrounded by controversy regarding their nosological aspects. The current study examined the prevalence rates of clinical cases of ED and MD through a two-phase study with gold standard clinical interview in a representative sample of 850 Spanish undergraduate men, of whom 141 were interviewed. Levels of body dissatisfaction, compulsive exercise, anxious-depressive symptoms and the amount of physical activity were also explored. A prevalence rate for ED of 1.4% and 1.3% for MD was found. No differences were observed between the clinical groups on scales related to body image, supporting the current perspective that MD as well as ED and Body Dysmorphic Disorder could be clustered in a new spectrum of body image disorders, where the behaviours performed to achieve body change could range from restriction or muscularity-oriented eating alterations to pathological exercise or cosmetic surgery. The usefulness of the cut-off points of the screening questionnaires in MD and ED in males are discussed.

Reticulate Skin Lesions: Practical Color-Based Algorithm for Initial Clinical Assessment. / Lesiones cutáneas reticulares: algoritmo clínico práctico basado en el color de la lesión para el abordaje inicial.

Reticular patterns are observed in a great variety of skin diseases. While these morphologic patterns are often highly distinctive, they are seldom discussed or studied in clinical contexts or recognized as a diagnostic category in their own right. Diseases presenting with reticulate skin lesions have multiple etiologies (tumors, infections, vascular disorders, inflammatory conditions, and metabolic or genetic alterations) and can range from relatively benign conditions to life-threatening ones. We review a selection of these diseases and propose a clinical diagnostic algorithm based on predominant coloring and clinical features to aid in their initial assessment.

[Translated article] Reticulate Skin Lesions: Practical Color-Based Algorithm for Initial Clinical Assessment.

Reticular patterns are observed in a great variety of skin diseases. While these morphologic patterns are often highly distinctive, they are seldom discussed or studied in clinical contexts or recognized as a diagnostic category in their own right. Diseases presenting with reticulate skin lesions have multiple etiologies (tumors, infections, vascular disorders, inflammatory conditions, and metabolic or genetic alterations) and can range from relatively benign conditions to life-threatening ones. We review a selection of these diseases and propose a clinical diagnostic algorithm based on predominant coloring and clinical features to aid in their initial assessment.

Psychological well-being and weight-related teasing in childhood obesity: a case-control study.

PURPOSE: The prevalence of childhood obesity continues to increase worldwide. The aims of this study were to (1) assess the psychological well-being and rates of teasing of Spanish children with obesity (OG) and compare them with their non-overweight peers (NG), and (2) analyze the mediating role of weight-related teasing on the relation between children's BMI z score and psychological well-being. METHODS: The cross-sectional study included 50 preadolescents with obesity, matched with non-overweight children according to age, sex, and socioeconomic status, who were assessed via self-report instruments measuring anxiety, depression, self-esteem, and teasing. RESULTS: The OG reported higher anxiety, depression, and teasing, and lower self-esteem. SEM revealed that children who scored worse on instruments assessing psychological well-being had higher BMI z scores. Weight-related teasing predicted poor psychological well-being scores and weight-related teasing mediated the relation between BMI and psychological well-being. CONCLUSIONS: The high rates of anxiety, depression, and weight-related teasing, as well as the low self-esteem, which was observed amongst the children with obesity, raise concerns about the quality of life of this population. Furthermore, the finding that weight-related teasing mediated the relationship between BMI and psychological well-being adds to a growing body of research, highlighting the harmful effects of weight-related stigma. Overall, these results highlight the importance of early intervention to assess for, and address, the presence of weight-related teasing and psychological well-being difficulties in preadolescents with obesity. LEVEL OF EVIDENCE: Level III, case-control study.

Investigation of the effect of pegbovigrastim on some periparturient immune disorders and performance in Mexican dairy herds.

This study analyzed the efficacy of pegbovigrastim (Imrestor, Elanco Animal Health, Greenfield, IN) on some health and production parameters in lactating dairy cows. Primiparous and multiparous Holsteins from 17 Mexican dairy herds (n = 10,238) were included in this study, which was conducted in 2015. Treated cows (n = 5,025) received Imrestor approximately 7 d before expected calving and again within 24 h after calving; control cows (n = 5,213) did not receive a placebo. Clinical mastitis (MAS; 0 to 30 DIM), retained placenta (RP), and clinical metritis (MET; 0 to 21 DIM) occurrences were recorded, as well as the number of medication days, medical treatments needed, and the number of days that milk was discarded due to medication administered for disease. Milk yield was measured from calving until 120 d in milk. Imrestor reduced the incidence of MAS by 25%, and the odds ratio of having mastitis in the first 30 d in milk was 35% greater for control cows than for Imrestor cows. Imrestor treatment reduced the number of medical treatments required for MAS by 6%, and less milk was discarded due to medication for MAS as a result of the Imrestor treatment. The incidence of RP was reduced by 4.15% with Imrestor and the odds of cows having RP were 4.6% greater for control than Imrestor treatments, but they did not differ. The MET incidence was increased by 17.1% with Imrestor. The use of Imrestor around parturition increased by 5.8% the odds of inseminating cows during the first 100 d after calving. Imrestor-treated multiparous cows with MAS produced 2.1 kg/d more milk than control cows with MAS during the first 30 d of their lactation. Imrestor-treated multiparous cows with MET produced 2.3 kg/d more milk than MET control cows during the first 120 d of their lactation. We conclude that Imrestor can help the dairy cow cope with immune periparturient disorders and can increase the milk yield of dairy cows due to a healthier transition, despite a reported increase in the incidence of MET.

[Hyperuricaemia and metabolic syndrome in obese children and adolescents]. / Hiperuricemia y componentes del síndrome metabólico en niños y adolescentes obesos.

INTRODUCTION: Hyperuricaemia has been suggested as an additional metabolic factor in adult obese patients, but it has not been sufficiently studied in paediatric. OBJECTIVES: To assess the relationship between serum uric acid levels (SUAL) with the level of general and visceral obesity, and other biochemical parameters in children and adolescents of Santiago, Chile. SUBJECTS AND METHOD: A cross sectional study was conducted on 770 children and adolescents (ages: 6-15 y.) from a public school in Santiago, Chile, of whom 227 (29%) were obese (BMI>2 SD, WHO growth standards). Ninety subjects were randomly selected and 77 with no other chronic disease (41 males) accepted to participate. Data was collected on weight, stature, abdominal circumference (AC), visceral adiposity using ultrasound, and other biochemical measurements including fasting glucose, insulin, serum lipids, aspartate aminotransferase (AST), alanine aminotransferase (ALT), and SUAL. RESULTS: The mean SUAL was 0.200±0.065 mmol/L, and was increased in children with hyperinsulinism (adjusted by age: 0.221±0.075 vs. 0.183±0.054 mmol/L; P<.01), with no significant differences according to HOMA. Differences were also found between children with ALT>or<26 U/mL: 0.238±0.070 vs. 0.178±0.054 mmol/L, P<.001. The logistic regression showed the increased SUAL was only associated with increased ALT. No significant differences were found in general or visceral adiposity measurements or fatty liver. CONCLUSIONS: Children and adolescents from Santiago, Chile have higher uric acid serum uric acid levels as well as an association with increased ALT and insulin. It is demonstrated in this study that uric acid should be measured in obese children and adolescents, and in their follow up.

Vapor-deposited glasses of methyl-m-toluate: How uniform is stable glass transformation?

AC chip nanocalorimetry is used to characterize vapor-deposited glasses of methyl-m-toluate (MMT). Physical vapor deposition can prepare MMT glasses that have lower heat capacity and significantly higher kinetic stability compared to liquid-cooled glasses. When heated, highly stable MMT glasses transform into the supercooled liquid via propagating fronts. We present the first quantitative analysis of the temporal and spatial uniformities of these transformation fronts. The front velocity varies by less than 4% over the duration of the transformation. For films 280 nm thick, the transformation rates at different spatial positions in the film differ by about 25%; this quantity may be related to spatially heterogeneous dynamics in the stable glass. Our characterization of the kinetic stability of MMT stable glasses extends previous dielectric experiments and is in excellent agreement with these results.

Role of fragility in the formation of highly stable organic glasses.

In situ dielectric spectroscopy has been used to characterize vapor-deposited glasses of methyl-m-toluate (MMT), an organic glass former with low fragility (m = 60). Deposition near 0.84T(g) produces glasses of very high kinetic stability; these materials are comparable in stability to the most stable glasses produced from more fragile glass formers. Highly stable glasses of MMT, when annealed above T(g), transform into the supercooled liquid by a heterogeneous mechanism. A constant velocity propagating front is initiated at the free surface and controls the transformation of thin films. The transition to a bulk-dominated transformation process occurs at 5 µm, the largest length scale reported for any glass. Contrary to recent conclusions, we find that physical vapor deposition can form highly stable organic glasses across the entire range of liquid fragilities.

Imaging of the Sinonasal Cavities.

This article describes the various abnormalities that affect the sinonasal cavities and discusses inflammations, tumors, and tumor-like conditions. Specific imaging evaluations that focus on the sinonasal cavities are described in more detail.

A phase II trial of gemcitabine, irinotecan and panitumumab in advanced cholangiocarcinoma.

BACKGROUND: Current data suggest that chemotherapy combinations may be superior to single agents in biliary tract cancer. The epidermal growth factor receptor (EGFR) pathway appears to be associated with tumor stage, prognosis and response to therapy. This trial was designed to evaluate the tolerability and efficacy of the combination of panitumumab, a monoclonal anti-EGFR antibody, with gemcitabine and irinotecan. PATIENTS AND METHODS: Patients with advanced (unresectable or metastatic) cholangiocarcinoma, ECOG PS 0-2, and adequate organ function were treated with panitumumab (9 mg/kg) on day 1, and gemcitabine (1000 mg/m(2)) and irinotecan (100 mg/m(2)) on days 1 and 8 of a 21-day cycle. The primary objective was to evaluate the 5-month progression-free survival (PFS). Secondary objectives included overall response rate (ORR) and overall survival (OS). Mutational analyses of EGFR, KRAS and BRAF were carried out when feasible. RESULTS: Thirty-five patients received a median of 7 (0-30) cycles. The most common grade 3/4 toxic effects were neutropenia (10 patients, 29%), thrombocytopenia (10 patients, 29%), skin rash (13 patients, 37%) and dehydration (9 patients, 26%). Two patients had CR, 9 had partial response (PR), and 15 had SD for a disease-control rate of 74% (by RECIST) in 28 assessable patients. Two patients went on to have surgical resection. The 5-month PFS was 69%. The median PFS was 9.7 months and the median OS was 12.9 months. In 17 testable samples, no EGFR or BRAF mutations were identified; there were 7 KRAS mutations, with no difference in OS by KRAS status. CONCLUSIONS: This study showed encouraging efficacy of this regimen with good tolerability. Further study in this area is warranted. Clinical Trials Number: The trial was registered with the National Cancer Institute (www.clinicaltrials.gov identifier NCT00948935).

Manipulating the properties of stable organic glasses using kinetic facilitation.

In contrast to ordinary glasses, when highly stable organic glasses are annealed at temperatures above T(g), they transform heterogeneously into the liquid state by a constant velocity propagating front that initiates at the free surface. The evolution of this growth front has been interpreted as kinetic facilitation, i.e., efficiently packed molecules become un-jammed only when mobility is available in adjacent regions. Here we use physical vapor deposition to prepare highly stable glasses of indomethacin in which mobile regions are either added to or eliminated from the samples in an attempt to use the kinetic facilitation concept to manipulate the properties of these materials. The addition of higher mobility layers in the interior of a thin stable glass film or at the substrate surface is shown to initiate new growth fronts, thus demonstrating that kinetic facilitation occurs independently of free surface mobility. Conversely, capping the free surface with a higher T(g) stable glass stops the growth front, apparently by eliminating surface mobility, thus increasing sample stability by slowing the transformation to the supercooled liquid.

Dynamics of glass-forming liquids. XVI. Observation of ultrastable glass transformation via dielectric spectroscopy.

The transformation of vapor-deposited ultrastable glasses of indomethacin (IMC) into the supercooled liquid state near T(g) is monitored by means of dielectric spectroscopy. Films with thickness between 400 and 800 nm are deposited on differential interdigitated electrode cells and their loss profiles are measured during isothermal annealing using a dual-channel impedance technique for frequencies between 0.03 and 100 Hz. All dielectric loss spectra observed during the transformation process can be explained by a volume fraction of the supercooled liquid that increases linearly with time. From the early stages of the transformation to the liquid that is formed via complete annealing of the ultrastable glass, the average dielectric relaxation time as well as the distribution of relaxation times of the liquid component are identical to those of the conventional liquid obtained by cooling the melt. The dependence of the transformation rate on the film thickness is consistent with a growth front mechanism for the direct conversion from the ultrastable glass to the equilibrium supercooled liquid. We conclude that the IMC liquid recovered from the ultrastable glass is structurally and dynamically identical to the conventional supercooled state.

Stable glasses of indomethacin and α,α,ß-tris-naphthylbenzene transform into ordinary supercooled liquids.

Secondary ion mass spectrometry has been used to characterize translational motion in vapor-deposited glasses of indomethacin (IMC) and α,α,ß-tris-naphthylbenzene (TNB). Vapor deposition onto substrates at ∼0.99 T(g) produced ordinary glasses that evolve according to fickian diffusion during annealing. The resulting self-diffusion coefficients for the supercooled liquids are in good agreement with previous reports. Deposition onto substrates at 0.85 T(g) produced highly stable glasses that transform with a propagating front mechanism. In contrast to previous reports, the liquid produced by this transformation has the same translational mobility as the ordinary supercooled liquid; we associate this result with lower impurity levels in the current samples. The front velocities for both TNB and IMC stable glasses are very similar functions of the translational self-diffusion coefficients of the supercooled liquids, consistent with view that the growth front velocity is controlled by mobility in the liquid adjacent to the stable glass.

Density and birefringence of a highly stable α,α,ß-trisnaphthylbenzene glass.

Spectroscopic ellipsometry has been used to understand the properties of α,α,ß-trisnaphthylbenzene (ααß-TNB) glasses vapor-deposited at a substrate temperature of 295 K (0.85 T(g)). In a single temperature ramping experiment, a range of properties of the as-deposited glass can be measured, including density, fictive temperature, onset temperature, thermal expansion coefficient, and birefringence. The vapor-deposited ααß-TNB glass is 1.3% more dense than the ordinary glass prepared by cooling at 1 K/min, is found to be birefringent, has a fictive temperature 35 K below that of the ordinary glass, and an onset temperature 20 K above that of the ordinary glass. The thermal expansion coefficient of the vapor-deposited ααß-TNB glass is 14% lower than that of the ordinary glass, indicating that lower portions of the potential energy landscape have more harmonic potential minima than the parts accessible to the ordinary glass.

Glass transition in ultrathin films of amorphous solid water.

Nanocalorimetry at ultrafast heating rates is used to investigate the glass transition of nanometer thick films of metastable amorphous solid water grown by vapor deposition in an ultrahigh vacuum environment. Apparent heat capacity curves exhibit characteristic features depending on the deposition temperature. While films grown at T ≥ 155 K are completely crystallized, those deposited at 90 K show a relaxation exotherm prior to crystallization. Films grown between 135 and 140 K and subsequently cooled down to 90 K reveal a clear endothermic feature before crystallization, which is compatible with a glass-to-liquid transition. The onset temperature is located at 174 K at a heating rate of 2.4 × 10(4) K/s and is independent of film thickness in the range of 16-150 nm. Comparison of our data with other calorimetric measurements at various heating rates suggests that water is a strong glass former in the deeply supercooled state.

[Incidence of accidental dura mater punctures in a university hospital: a prospective observational study]. / Incidencia de punción accidental de duramadre en un hospital universitario. Estudio prospectivo observacional.

OBJECTIVE: Accidental dura mater puncture is a potential complication during epidural block, and may be associated with multiple factors. Our objective was to determine the prevalence and risk factors of accidental dural puncture in a university hospital, evaluating the differences in the number of complications during different working hours. MATERIAL AND METHODS: A prospective observational study was conducted on all women who requested regional anaesthesia in the Epidural Analgesia Unit between 1 January 2009 and 1 January 2011, and who fulfilled the inclusion criteria. The technique employed to control labour pains was epidural analgesia. RESULTS: A total of 12,480 pregnant women were included. The prevalence of accidental dura mater puncture was 0.4% (50 patients). Of these, 28% were due to medical residents. More accidental dura mater punctures were observed during September and in the afternoon shift. CONCLUSIONS: The prevalence of accidental dura mater puncture is similar to other patient series. In ours, tiredness or lack of sleep did not influence the incidence of complications in analgesia for labour pains in a 24 hour care unit. This may be due to the distribution of on-call shifts not exceeding more than 6 hours.

L-shell ionization of Cd: Structure of the x-ray emission spectrum.

The cadmium L x-ray spectrum induced by electron impact was analyzed in detail. The measurements were performed on a bulk pure sample using a commercial wavelength dispersive spectrometer, and the spectrum was processed with a parameter optimization method previously developed. This procedure permitted the determination of characteristic energies, relative transition probabilities and natural linewidths for this element. The results obtained here were compared to the data found in the literature, when available. Spectral structures related to satellite and radiative Auger Effect emissions were also analyzed, assessing energy shifts and relative intensities. Some of these parameters were determined for the first time, even in overlapping peaks and weak transitions, which was possible due to the robustness of the spectral processing method used.

Accelerated aging in ultrathin films of a molecular glass former.

We report the thermodynamic measurement of the enthalpy released during the aging of supported films of a molecular glass former, toluene, at temperatures well below the glass transition temperature. By using microfabricated devices with very short equilibration times (below 1 s), we evidence a remarkable variation of the relaxation rate on decreasing film thickness from 100 nm down to a 7 nm thick film. Our results demonstrate that surface atoms are more efficient than bulk atoms in attaining low energy configurations within the potential energy landscape.