DSC study of transitions involved in thermal treatment of foamable mixtures of PE and EVA copolymer with azodicarbonamide

The transitions and reactions involved in the thermal processing of binary mixtures of polyethylene and poly(ethylene-co-vinyl acetate) copolymers with different concentrations of a foaming agent (azodicarbonamide) were studied using differential scanning calorimetry (DSC). The effect of ZnO as a kicker also was discussed. The temperature at the maximum rate and the heat evolved were measured for all the processes—melting, transitions, and reactions—all the mixtures prepared were measured and compared. Azodicarbonamide decomposed differently depending on the polymeric matrix. These data can be very useful for the plastic processing industry.

Role of the denitrifying Haloarchaea in the treatment of nitrite-brines

Haloferax mediterranei is a denitrifying halophilic archaeon able to reduce nitrate and nitrite under oxic and anoxic conditions. In the presence of oxygen, nitrate and nitrite are used as nitrogen sources for growth. Under oxygen scarcity,this haloarchaeon uses both ions as electron acceptors via a denitrification pathway. In the present work, the maximal nitriteconcentration tolerated by this organism was determined by studying the growth of H. mediterranei in minimal medium containing30, 40 and 50 mM nitrite as sole nitrogen source and under initial oxic conditions at 42 °C. The results showed theability of H. mediterranei to withstand nitrite concentrations up to 50 mM. At the beginning of the incubation, nitrate wasdetected in the medium, probably due to the spontaneous oxidation of nitrite under the initial oxic conditions. The completeremoval of nitrite and nitrate was accomplished in most of the tested conditions, except in culture medium containing 50 mMnitrite, suggesting that this concentration compromised the denitrification capacity of the cells. Nitrite and nitrate reductases activities were analyzed at different growth stages of H. mediterranei. In all cases, the activities of the respiratory enzymeswere higher than their assimilative counterparts; this was especially the case for NirK. The denitrifying and possibly detoxifyingrole of this enzyme might explain the high nitrite tolerance of H. mediterranei. This archaeon was also able to remove60 % of the nitrate and 75 % of the nitrite initially present in brine samples collected from a wastewater treatment facility.These results suggest that H. mediterranei, and probably other halophilic denitrifying Archaea, are suitable candidates for thebioremediation of brines with high nitrite and nitrate concentrations.

Clinical pathway intervention compliance and effectiveness when used in the treatment of patients with severe sepsis and septic shock at an Intensive Care Unit in Spain

The purpose of this quasi-experimental study was to assess levels of compliance with the intervention bundles contained in a clinical pathway used in the treatment of patients with severe sepsis and septic shock, and to analyze the pathway’s impact on survival and duration of hospital stays. We used data on 125 patients in an Intensive Care Unit, divided into a control group (N=84) and an intervention group (N=41). Levels of compliance increased from 13.1% to 29.3% in 5 resuscitation bundle interventions and from 14.3% to 22% in 3 monitoring bundle interventions. In-hospital mortality at 28 days decreased by 11.2% and the duration of hospital stay was reduced by 5 days. Although compliance was low, the intervention enhanced adherence to the instructions given in the clinical pathway and we observed a decline in mortality at 28 days and shorter hospital stays.

Social anxiety and self-concept in adolescence

This study analyzes the relationships between social anxiety and dimensions of self-concept in a sample of 2022 (50.1% males) Spanish adolescents, ranging in age from 12 to 16 year-olds. The social anxiety was assessed by the Social Phobia and Anxiety Inventory (SPAI), and self-concept was measured with the Self-Description Questionnaire II (SDQ-II). Logistic regression analyses show that adolescents with social anxiety are more likely to negatively perceive their relationship with opposite sex peers and have lower scores in self-esteem than students without social anxiety. Furthermore, in most logistic models, students with social anxiety also show a higher probability of perceiving their relation with peers of the same sex in a negative way, considering worse student, less attractive and athletic, and more emotional instable than students without social anxiety. The relevance of sex and grade in the relationship between social anxiety and self-concept in adolescence is discussed.

Subclinical social anxiety and academic performance in adolescence: analysis of theoretical and practical implications

This study analyses the relationship between self-reported social anxiety and academic performance in a sample of 1,616 Spanish students (52.1% males) in compulsory secondary education, aged 12 to 16 years old. Social anxiety was assessed by the Social Phobia and Anxiety Inventory (SPAI) and academic performance was measured with school grades and failing grades. Results reveal that adolescents with social anxiety show a similar academic performance to adolescents without social anxiety. Although t tests found some significant differences in academic grades and number of failing grades, the effect size analysis showed that these differences had no empirical relevance. These findings are discussed considering the gender and grade levels and their theoretical and practical implication.