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To guarantee a long lifetime of perovskite-based photovoltaics, the selected materials need to survive relatively high-temperature stress during the solar cell operation. Highly efficient n-i-p perovskite solar cells (PSCs) often degrade at high operational temperatures due to morphological instability of the hole transport material 2,2',7,7'-tetrakis ( N , N -di- p -methoxyphenyl-amine)9,9'-spirobifluorene (Spiro-OMeTAD). We discovered that the detrimental large-domain spiro-OMeTAD crystallization is caused by the simultaneous presence of tert -butylpyridine ( t BP) additive and gold (Au) as a capping layer. Based on this discovery and our understanding, we demonstrated facile strategies that successfully stabilize the amorphous phase of spiro-OMeTAD film. As a result, the thermal stability of n-i-p PSCs is largely improved. After the spiro-OMeTAD films in the PSCs were stressed for 1032 h at 85 °C in the dark in nitrogen environment, reference PSCs retained only 22% of their initial average power conversion efficiency (PCE), while the best target PSCs retained 85% relative average PCE. Our work suggests facile ways to realize efficient and thermally stable spiro-OMeTAD containing n-i-p PSCs.

With the realization of highly efficient perovskite solar cells, the long-term stability of these devices is the key challenge hindering their commercialization. In this work, we study the temperature-dependent stability of perovskite solar cells and develop a model capable of predicting the lifetime and energy yield of perovskite solar cells outdoors. This model results from the measurement of the kinetics governing the degradation of perovskite solar cells at elevated temperatures. The individual analysis of all key current-voltage parameters enables the prediction of device performance under thermal stress with high precision. An extrapolation of the device lifetime at various European locations based on historical weather data illustrates the relation between the laboratory data and real-world applications. Finally, the understanding of the degradation mechanisms affecting perovskite solar cells allows the definition and implementation of strategies to enhance the thermal stability of perovskite solar cells.

Background: Chrysobalanus icaco is a medicinal plant commonly used to treat fungal infections in Brazilian Amazonian region., Objective: This work aimed to evaluate the antifungal activity of the hydroalcoholic extract of C. icaco (HECi) against oral clinical isolates of Candida spp. and to determine the pharmacognostic parameters of the herbal drug and the phytochemical characteristics of HECi., Materials and Methods: The pharmacognostic characterization was performed using pharmacopoeial techniques. Phytochemical screening, total flavonoid content, and high-performance liquid chromatography (HPLC) analysis were used to investigate the chemical composition of the HECi. A broth microdilution method was used to determine the antifungal activity of the extract against 11 oral clinical isolates of Candida spp., Results: Herbal drug presented parameters which were within the limits set forth in current Brazilian legislation. A high amount of flavonoid content (132,959.33 ± 12,598.23 μg quercetin equivalent/g of extract) was found in HECi. Flavonoids such as myricetin and rutin were detected in the extract by HPLC analyses. HECi showed antifungal activity against oral isolates of Candida albicans and Candida parapsilosis (minimum inhibitory concentrations [MIC] 3.12 and 6.25 mg/mL, respectively), and C. albicans American American Type Culture Collection (MIC <1.56 mg/mL)., Conclusion: HECi was shown to possess antifungal activity against Candida species with clinical importance in the development of oral candidiasis, and these activities may be related to its chemical composition. The antifungal activity detected for C. icaco against Candida species with clinical importance in the development of oral candidiasis can be attributed to the presence of flavonoids in HECi, characterized by chromatographic and spectroscopic techniques., Summary: Chrysobalanus icaco presents a high amount of flavonoids in its constitutionLC analysis was able to identify the flavonoids myricetin and rutin in C. icaco hydroalcoholic extractThe C. icaco hydroalcoholic extract inhibits the growth of oral clinical isolates of Candida spp. and Candida albicans American Type Culture Collection. Abbreviations Used : HECi: Hydroalcoholic extract of C. icaco ; HPLC: High performance liquid chromatography; AlCl3: Aluminum chloride; DMSO: Dimethyl sulfoxide; CH3NOONa: Sodium acetate; MTT: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide; ATCC: American Type Culture Collection; EMBRAPA: Brazilian Agricultural Research Corporation - Eastern Amazon; v/v: Volume per volume; SD: Standard deviation; TFC: Total flavonoid content; w/v: Weight per volume; ELSD: Evaporative light scattering detector; DAD: Diode-arrange detector; UFPA: Federal University of Pará; IEC: Evandro Chagas Institute; INCQS-FIOCRUZ: National Institute of Quality Control in Health - Fundação Oswaldo Cruz; SDA: Sabouraud Dextrose Agar; CFU: Colony-forming units; MIC: Minimum inhibitory concentrations; MFC: Minimum fungicidal concentrations., Competing Interests: There are no conflicts of interest.

Fullerene-based molecules are the archetypical electron-accepting materials for organic photovoltaic devices. A detailed knowledge of the degradation mechanisms that occur in C60 layers will aid in the development of more stable organic solar cells. Here, the impact of storage in air on the optical and electrical properties of C60 is studied in thin films and in devices. Atmospheric exposure induces oxygen-trap states that are 0.19 eV below the LUMO of the fullerene C60. Moreover, oxygen causes a 4-fold decrease of the exciton lifetime in C60 layers, resulting in a 40% drop of short-circuit current from optimized planar heterojunction solar cells. The presence of oxygen-trap states increases the saturation current of the device, resulting in a 20% loss of open-circuit voltage. Design guidelines are outlined to improve air stability for fullerene-containing devices.

The objective of this study was to evaluate the effects of replacing monensin (MON) with a spray-dried multivalent polyclonal antibody preparation (PAP) against several ruminal microorganisms on feedlot performance, carcass characteristics, feeding behavior, blood gas profile, and the rumenitis incidence of Brangus and Nellore yearling bulls. The study was designed as a completely randomized design with a 2 × 2 factorial arrangement, replicated 6 times (4 bulls per pen and a total of 24 pens), in which bulls ( = 48) of each biotype were fed diets containing either MON fed at 300 mg/d or PAP fed at 3 g/d. No significant feed additive main effects were observed for ADG ( = 0.27), G:F ( = 0.28), HCW ( = 0.99), or dressing percentage ( = 0.80). However, bulls receiving PAP had greater DMI ( = 0.02) and larger ( = 0.02) final LM area as well as greater ( < 0.01) blood concentrations of bicarbonate and base excess in the extracellular fluid than bulls receiving MON. Brangus bulls had greater ( < 0.01) ADG and DMI expressed in kilograms, final BW, heavier HCW, and larger initial and final LM area than Nellore bulls. However, Nellore bulls had greater daily DMI fluctuation ( < 0.01), expressed as a percentage, and greater incidence of rumenitis ( = 0.05) than Brangus bulls. In addition, Brangus bulls had greater ( < 0.01) DMI per meal and also presented lower ( < 0.01) DM and NDF rumination rates when compared with Nellore bulls. Significant interactions ( < 0.05) between biotype and feed additive were observed for SFA, unsaturated fatty acids (UFA), MUFA, and PUFA concentrations in adipose tissues. When Nellore bulls were fed PAP, fat had greater ( < 0.05) SFA and PUFA contents but less ( < 0.01) UFA and MUFA than Nellore bulls receiving MON. For Brangus bulls, MON led to greater ( < 0.05) SFA and PUFA and less ( < 0.05) UFA and MUFA than Brangus bulls fed PAP. Feeding a spray-dried PAP led to similar feedlot performance compared with that when feeding MON. Spray-dried PAP might provide a new technology alternative to ionophores.

Ethnopharmacological Relevance: Petiveria alliacea L. (Phytolaccaceae) is a perennial shrub native to the Amazon region and other tropical areas such as Central America and the Caribbean. Popularly known as mucuracaá, P. alliacea is used in the folk medicine for a broad variety of therapeutic purpose and also in religious ceremonies by slaves as a sedative, which highlights its properties on the Central Nervous System (CNS)., Aim of the Study: The present study evaluated the effects of the P. alliacea leaves hydroalcoholic extract (PaLHE) on the cognition, including learning and memory., Material and Methods: Three-month-old male and female Wistar rats (n=8-10/group) were administered with 900mg/kg of PaLHE. The behavioral assays included Step-down Inhibitory avoidance (IA) and Morris Water Maze (MWM) tests., Results: Consistent with our previous reports, P. alliacea improved long-term memory. It also exerted previously unreported effects on short-term and spatial memory improvement, and increased learning in the tasks., Conclusions: The P. alliacea extract elicited mnemonic effects and improved the learning process in both IA and MWM tests. Our results highlight the importance of further studies in order to identify the active substances of the PaLHE and investigate the pharmacological mechanisms that underlies the reported effects., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

Background: There are scarce epidemiological data on cardiovascular risk profile of chronic hemodialysis patients in Brazil., Objective: The CORDIAL study was designed to evaluate cardiovascular risk factors and follow up a hemodialysis population in a Brazilian metropolitan city., Methods: All patients undergoing regular hemodialysis for chronic renal failure in all fifteen nephrology centers of Porto Alegre were considered for inclusion in the baseline phase of the CORDIAL study. Clinical, laboratory and demographic data were obtained in medical records and in structured individual interviews performed in all patients by trained researchers., Results: A total of 1215 patients were included (97.3% of all hemodialysis patients in the city of Porto Alegre). Their average age was 58.3 years old, 59.5% were male and 62.8% were white. The prevalence of cardiovascular risk factors observed was 87.5% for hypertension, 84.7% for dyslipidemia, 73.1% for sedentary lifestyle, 53.7% for tobacco use, and 35.8% for diabetes. In a multivariate adjusted analysis, we found that sedentary lifestyle (p = 0.032, PR 1.08 - 95%CI: 1.01-1.15), dyslipidemia (p = 0.019, PR 1.08 - 95%CI: 1.01-1.14), and obesity (p < 0.001, PR 1.96 - 95%CI: 1.45-2.63) were more frequent in women; and hypertension (p = 0.018, PR 1.06 - 95%CI: 1.01-1.11) and tobacco use (p = 0.006, PR 2.7 - 95%CI: 1.79-4.17) were more often found among patients under 65 years old. Sedentary lifestyle was independently associated with time in dialysis less than 12 months (p < 0.001, PR 1.23 - 95% CI: 1.14-1.33)., Conclusion: Hemodialysis patients in this southern metropolitan Brazilian city have a high prevalence of cardiovascular risk factors resembling many northern countries.

Purpose: To evaluate time trends in physical activity among adolescents aged 10 to 19 years living in southern Brazil over a 7-year period., Methods: Two population-based cross-sectional surveys with similar methodologies were carried out in the city of Pelotas, Brazil, in 2005 and 2012. Leisure-time and transport-related physical activity were measured using a validated questionnaire. A cut-off point of 300 minutes per week was used to classify adolescents as active or not. We also analyzed the two domains of physical activity (leisure time and transportation) separately., Results: The prevalence of physical inactivity was 69.6% (95% CI 66.5-73.2) in 2005 and 69.9% (95% CI 66.5-72.7) in 2012. The percentage of active adolescents in leisure time also remained stable in the period (26.3% in 2005 [95% CI 23.3-29.2] vs. 28.1% in 2012 [95% CI 24.9-31.4]). Among boys, we observed an increase in the practice of some leisure-time activities-weight lifting (87%) and running (78%)-and a decline in others-volleyball (61%) and basketball (56%). Among girls, the only significant difference was an increase in the practice of weight lifting (271%). The prevalence of active commuting to and from school declined from 69% (95% CI 65.6-72.4) in 2005 to 56.5% (95% CI 52.5-60.2) in 2012., Conclusions: There was a significant decline in active commuting to school among adolescents. Interventions promoting active commuting modes to school are urgently needed in Brazil., (Copyright © 2014 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.)

Background: We aimed to describe levels of physical activity (PA) in adolescents living in southern Brazil and to explore associations between PA levels and demographic, socioeconomic, health-related, and parental variables. A further aim was to test the validity and reliability of the questionnaire used., Methods: We conducted a population-based, cross-sectional study including 857 adolescents selected randomly. Insufficient PA was defined as <300 min/wk of MVPA. PA data collected by questionnaire were compared with pedometer counts and with a longer version of the questionnaire in a subsample of 92 adolescents., Results: Reliability of the questionnaire was good, and its validity in comparison with a longer questionnaire was also satisfactory. In comparison with pedometer data, the questionnaire presented moderate agreement. The prevalence of insufficient PA in the whole sample was 69.8% (95% CI = 66.7-72.9). Boys were more active than girls. The prevalence of insufficient PA increased with age in girls but not in boys. Among boys, those from low socioeconomic levels were more likely to be sedentary. Among girls, paternal PA was directly associated with adolescent activity levels., Conclusions: Urgent strategies aimed at increasing levels of activity of adolescents are necessary in Brazil given the high prevalence of insufficient PA detected in this study. The variables associated with insufficient PA varied between boys and girls.

Objectives: The objective of this study was to evaluate physical activity (PA) levels in adults and their association with sex, age, and education level across categories of body mass index (BMI)., Methods: We conducted a population-based, cross-sectional study including 3100 individuals age >20 years living in Pelotas, Brazil. PA was assessed using the leisure-time section of the long International Physical Activity Questionnaire. "No PA" was defined as zero minutes of activity/ week; "insufficient PA" was defined as <150 minutes of activity/week; "high PA" was defined as > or =500 minutes of activity/week. BMI was categorized into normal (<25 kg/m2), overweight (25-29.9 kg/m2), and obesity (>or =30 kg/m2)., Results: The prevalence of insufficient PA was 71.6% among normal BMI subjects, 71.3% among overweight individuals, and 73.7% among obese ones (P = .67). No PA and high PA were also not associated with BMI. The associations between sex, age, and education level and PA levels tended to be stronger among normal-weight individuals compared with overweight and obese individuals. Among the obese, most associations were not significant. Among normal-weight individuals, higher PA levels were observed in men, young adults, and those with higher education., Conclusions: Variables associated with leisure-time PA differed between normalweight, overweight, and obese individuals. Studies on PA correlates might benefit from stratifying by BMI.

Objectives: Subjective sleep complaints have been reported in up to 80% of patients with end stage renal disease (ESRD). In these patients, sleep disturbances manifesting as insomnia, sleep apnea syndrome, restless leg syndrome (RLS), periodic limb movement disorder and excessive daytime sleepiness (EDS) have been frequently reported. Moreover, studies about the role of dialysis shift on sleep abnormalities, morbidity and mortality are still scarce. The aim of this study was to investigate the influence of dialysis shift on the quality of sleep and sleep abnormalities in patients with ESRD., Methods: We studied one hundred consecutive patients from a dialysis center. Quality of sleep was assessed by the Pittsburgh Sleep Quality Index and subjective EDS by the Epworth Sleepiness Scale. Restless leg syndrome was diagnosed using the four minimum criteria defined by the International Restless Legs Syndrome Study Group. Clinical and laboratory parameters were obtained by interview and chart review. Adequacy of dialysis was evaluated by the Kt/V index., Results: Poor quality sleep (PSQI>6) was found in 75% of cases and was associated with RLS (p=0.004) and with snoring (p=0.016). EDS (ESS>10) was present in 28% of cases. Patients with EDS (1.33+/-0.29) had lower values of the Kt/v index (P=0.01) than those without EDS (1.52+/-0.32). RLS was present in 48% of cases. Irrespective of dialysis shift, poor quality sleep, EDS and RLS were not different among patients., Conclusion: Poor quality sleep, EDS and RLS were common and not related to dialysis shift.

Objective: To describe the evolution of the epidemiological research on physical activity in Brazil., Methods: A systematic review of the literature was carried out in electronic databases (Medline/PubMed, Lilacs, Ovid, Science Direct, BioMed Central and High Wire), non-indexed Brazilian journals, query by specific authors, and contact with other researchers. The inclusion criteria were: the sample should be representative of a defined population; sample size equal to or greater than 500 individuals; data collection in Brazil; measurement of physical activity; and report of data on this variable., Results: A total of 42 studies were reviewed. The first study was published in 1990, and there has been a clear growth in the number of publications since 2000. Great regional disparities were seen and most studies were carried out in the Southeast and South regions. Almost all studies (93%) used questionnaires but operational definitions of sedentary lifestyle and questionnaires used varied markedly across studies preventing result comparisons., Conclusions: Although the literature on physical activity in Brazil has quantitatively increased, methodological limitations make it difficult to compare study results. Therefore, standardization of instruments and definitions is essential for the improvement of scientific knowledge in the area.

Objective: Pulmonary complications are common after abdominal surgery. Although a variety of risk factors have been described for these complications, studies so far have focused on elective interventions. The aim of this study was to determine the incidence and predictors of pulmonary complications following emergency abdominal surgery., Methods: This was a prospective cohort study. Pre and intra-operative data were collected through interview and chart review and their association with the occurrence of postoperative pulmonary complications (PPC) were analyzed., Results: Two hundred and sixty-six consecutive adult patients were included and seventy-five (28.2%) developed PPC. Age >50 years (adjusted OR=3.86; P<0.001), body mass index (BMI) <21 kg/m(2) or 30 kg/m(2) (adjusted OR=2.43; P=0.007) and upper or upper/lower abdominal incision (adjusted OR=2.57; P=0.027) were independently associated with PPC. Patients submitted to multiple procedures tended to be at a higher risk for PPC (adjusted OR=1.73; P=0.079). The development of PPC was associated with prolonged hospital stay (P<0.001) and increased death rate (P<0.001)., Conclusions: Pulmonary complications are frequent among patients undergoing abdominal emergency surgery and lead to increased length of hospital stay and death rate. Older age, abnormal BMI, upper or upper/lower abdominal incision and multiple procedures are predictors of PPC in this setting.

Truck drivers are more likely to suffer severe injury and death due to certain truck driving characteristics. Identifying and preventing factors associated with accidents in this population is important to minimize damage and improve road safety. Excessive daytime sleepiness is a major public health problem, leading to impaired cognitive function, reduced alertness, and increased risk of motor vehicle crashes. The aim of this cross-sectional study was to determine the prevalence and predictors of hypersomnolence (defined as an Epworth Sleepiness Scale score greater than 10) among truck drivers. Three hundred male truck drivers were studied. Quality of sleep was assessed by the Pittsburgh Sleep Quality Index, and the association between demographic, clinical, and occupational data with excessive sleepiness was analyzed. The mean daily sleep duration was 5.6+/-1.3 h, and poor quality of sleep was found in 46.3% of the individuals. Hypersomnolence was found in 46% of the drivers and was associated with younger age, snoring, and working >10 h without rest. A positive correlation between hypersomnolence and previous accidents was detected (p=0.005). These results show that sleep deprivation and hypersomnolence are frequent among truck drivers. The treatment of sleep-disordered breathing and the implementation of educational programs, particularly targeting younger drivers and promoting increased awareness of the deleterious effects of sleep loss and work overload, may help to reduce hypersomnolence and accidents among truck drivers.