283 research outputs found

    Un listado de la familia Bembicidae (Hymenoptera: Apoidea) de TĂșnez

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    A checklist of family Bembicidae from Tunisia is compiled based on data available in the literature, new material collected from different localities in Tunisia between 2017 and 2019, and some specimens hosted in the MusĂ©um National d’Histoire Naturelle, Paris, France. As a result, 49 species and two subspecies in 16 genera of the family Bembicidae are recorded. Two genera: Psammaecius Lepeletier de Saint Fargeau, 1832, and Brachystegus A. Costa, 1859, are reported in this study for the first time. This is in addition to nine species and subspecies: Alysson ratzeburgi Dahlbom, 1843, Psammaecius eremorum de Beaumont, 1952, Stizoides klugii (F. Smith, 1856), Stizus fuscatus Morice, 1897, Stizus niloticus saharae Roth, 1934, Stizus pubescens arenarum Handlirsch, 1892, Stizus ruficornis strigatus Mochi, 1939, Stizus vespoides (Walker, 1871) and Brachystegus braueri (Handlirsch, 1887) that are new for the Tunisian fauna. New localities are also reported for several species and subspecies that had already been reported from Tunisia. Identified taxa are illustrated by digital photographs and their global and Tunisian distribution is presented.Se recopila una lista de la familia Bembicidae en TĂșnez basada en los datos disponibles en la literatura, en nuevo material recolectado de diferentes localidades de TĂșnez entre 2017 y 2019, y algunos especĂ­menes conservados en el MusĂ©um National d’Histoire Naturelle, ParĂ­s, Francia. Como resultado, se registraron 49 especies y dos subespecies en 16 gĂ©neros de la familia Bembicidae. Dos gĂ©neros: Psammaecius Lepeletier de Saint Fargeau, 1832 y Brachystegus A. Costa, 1859 se reportan en este estudio por primera vez. Esto se suma a nueve especies y subespecies: Alysson ratzeburgi Dahlbom, 1843, Psammaecius eremorum de Beaumont, 1952, Stizoides klugii (F. Smith, 1856), Stizus fuscatus Morice, 1897, Stizus niloticus saharae Roth, 1934, Stizus pubescens arenarum Handlirsch, 1892, Stizus ruficornis strigatus Mochi, 1939, Stizus vespoides (Walker, 1871) y Brachystegus braueri (Handlirsch, 1887) que son nuevas para la fauna tunecina. TambiĂ©n se han encontrado nuevas localidades para varis especies y subespecies, que ya habĂ­an sido reportadadas de TĂșnez. Los taxones identificados se ilustran mediante fotografĂ­as digitales y se presenta su distribuciĂłn global y en TĂșnez

    Insecticidal Effects of Monoterpenes on Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae)

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    Twenty eight monoterpenes including monoterpene hydrocarbons and oxygenated monoterpenes (borneol, borynl acetate, camphene, camphor, 3-carene, carvone, 1,8-cineole, citronellal, ÎČ-citronellene, ÎČ-citronellol, dihydrocarvone, fenchol, fenchone, geranyl acetate, isomenthol, limonene, limonene oxide, linalool, linalyl acetate, menthol, menthone, myrcene, nerol, neryl acetate, α-pinene, ÎČ-pinene, terpinen-4-ol, α-terpineol), the active compounds of essential oils obtained from different plant species were tested against adults of Sitophilus zeamais Motschulsky under laboratory conditions. The monoterpenes were applied at contents of 10, 20 and 30 ÎŒl for liquid compounds and 10, 20 and 30 ÎŒg for solid compounds. The results show that most of the monoterpenes have significantly insecticidal effect on the tested insects. Insecticidal effects of monoterpene hydrocarbons were found to be lower than those of oxygenated monoterpenes. The ketone and aldehyde and epoxide derivatives of oxygenated monoterpenes were also found to be more toxic as compared with their other derivatives. Mortality percentage of S. zeamais adults, after 96th h of exposure at the maximum dose (30 ÎŒl/ÎŒg) of oxygenated monoterpenes including borneol, fenchol, linalool, menthol, terpinen-4-ol, α-terpineol (alcohols group); 1,8-cineole, limonene oxide (epoxides group); camphor, carvone, citronellal, dihydrocarvone, fenchone, menthone (ketones and aldehydes group) and neryl acetate (esters group) attained 100%. Concurrently, 3-carene from monoterpene hydrocarbons showed 100% mortality after 96th h of exposure at the maximum dose (30 ÎŒl). Carvone, dihydrocarvone, fenchone, limonene oxide, menthone and terpinen-4-ol from these compounds showed 100% insecticidal effect after 48th h of exposure. Among the monoterpenes tested, carvone, dihydrocarvone, menthone and terpinen-4-ol showed the strongest insecticidal activities with 100% of mortality at all doses (96 h after treatment) and then 1,8-cineole, fenchone, linalool and limonene oxide showed stronger insecticidal activities in comparison with other monoterpenes with lethal doses (LD50) values of 1.989, 2.445, 2.445 and 3.235 ÎŒl (96 h after treatment) against the test insects, respectively. Mortality rate of S. zeamais adults increased significantly (p < 0.01), as the dosage level and/or exposure time increased. Based on the present results, it can be concluded that the oxygenated monoterpenes may have a potential action for control of S. zeamais adults

    Rational Molecular Design Enables Efficient Blue TADF−OLEDs with Flexible Graphene Substrate

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    Observation of thermally activated delayed fluorescence (TADF) in conjugated systems redefined the molecular design approach to realize highly efficient organic light emitting diodes (OLEDs) in the early 2010s. Enabling effective reverse intersystem crossing (RISC) by minimizing the difference between singlet and triplet excited state energies (ΔEST) is proven to be a widely applicable and fruitful approach, which results in remarkable external quantum efficiencies (EQE). The efficacy of RISC in these systems is mainly dictated by the first-order mixing coefficient (λ), which is proportional to spin-orbit coupling (HSO) and inversely proportional to ΔEST. While minimizing ΔEST has been the focus of the OLED community over the last decade, the effect of HSO in these systems is largely overlooked. Here, molecular systems with increased HSO are designed and synthesized by substituting selected heteroatoms of high-performance TADF materials with heavy-atom selenium. A new series of multicolor TADF materials with remarkable EQEs are achieved. One of these materials, SeDF-B, results in pure blue emission with EQEs approaching 20%. Additionally, flexible graphene-based electrodes are developed for OLEDs and revealed to have similar performance as standard indium tin oxide (ITO) in most cases. These devices are the first report of TADF based OLEDs that utilize graphene-based anodes

    Construction of amperometric biosensor modified with conducting polymer/carbon dots for the analysis of catechol

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    Phenolic compounds used in food industries and pesticide industry, are environmentally toxic and pollute the rivers and ground water. For that reason, detection of phenolic compounds such as catechol by using simple, efficient and cost‐effective devices have been becoming increasingly popular. In this study, a suitable and a novel matrix was composed using a novel conjugated polymer, namely poly[1‐(5‐(4,8‐bis(5‐(2‐ethylhexyl)thiophen‐2‐yl)benzo[1,2‐b:4,5‐b']dithiophen‐2‐yl)furan‐2‐yl)‐5‐(2‐ethylhexyl)‐3‐(furan‐2‐yl)‐4H thieno[3,4‐c]pyrrole‐4,6(5H)‐dione] (PFTBDT) and carbon dots (CDs) to detect catechol. PFTBDT and CDs were synthesized and the optoelectronic properties of PFTBDT were investigated via electrochemical and spectroelectrochemical studies. Laccase enzyme was immobilized onto the constructed film matrix on the graphite electrode. The proposed biosensor was found to have a low detection limit (1.23 ΌM) and a high sensitivity (737.44 ΌA/mM.cm−2) with a linear range of 1.25–175 ΌM. Finally, the applicability of the proposed enzymatic biosensor was evaluated in a tap water sample and a satisfactory recovery (96–104%) was obtained for catechol determination.Publisher's Versio

    Internet addiction, fatigue, and sleep problems among adolescent students: a large-scale study

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    Aim: The aim of the present study was to examine the association between Internet Addiction (IA), fatigue, and sleep problems among university students. Methods: A total of 3,000 Turkish students aged 18 to 25 years were approached and 2,350 students (78.3%) participated in this cross-sectional study from April 2017 to September 2017 in public and private universities in Istanbul. Data were collected via a structured questionnaire including socio-demographic details, lifestyle and dietary habits, Internet Addiction Test (IAT), Fatigue Scale, and Epworth Sleepiness Scale [ESS]. Descriptive statistics, multivariate and factorial analyses were performed. Results: The overall prevalence of IA among the studied population was 17.7%. There were significant differences between gender, family income, father’s occupation, school performance, frequency and duration of watching television, physical activity, internet use duration, and sleep duration (all p<0.001). Significant differences were also found between participants with IA and those without IA in having headaches, blurred vision, double vision, hurting eyes, hearing problems, and eating fast food frequently (all p<0.001). Using multivariate regression analysis, the duration of internet use, physical and mental symptoms, headache, hurting eyes, tired eyes, hearing problems and ESS scores were significantly associated with (and primary predictors of) IA. Conclusion: The present study demonstrated that IA was associated with poor dietary habits, sleep problems, and fatigue symptoms

    Age- and region-specific hepatitis B prevalence in Turkey estimated using generalized linear mixed models: a systematic review

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    Toy M, Önder FO, Wörmann T, et al. Age- and region-specific hepatitis B prevalence in Turkey estimated using generalized linear mixed models: a systematic review. BMC infectious diseases. 2011;11(1): 337.BACKGROUND: To provide a clear picture of the current hepatitis B situation, the authors performed a systematic review to estimate the age- and region-specific prevalence of chronic hepatitis B (CHB) in Turkey. METHODS: A total of 339 studies with original data on the prevalence of hepatitis B surface antigen (HBsAg) in Turkey and published between 1999 and 2009 were identified through a search of electronic databases, by reviewing citations, and by writing to authors. After a critical assessment, the authors included 129 studies, divided into categories: 'age-specific'; 'region-specific'; and 'specific population group'. To account for the differences among the studies, a generalized linear mixed model was used to estimate the overall prevalence across all age groups and regions. For specific population groups, the authors calculated the weighted mean prevalence. RESULTS: The estimated overall population prevalence was 4.57, 95% confidence interval (CI): 3.58, 5.76, and the estimated total number of CHB cases was about 3.3 million. The outcomes of the age-specific groups varied from 2.84, (95% CI: 2.60, 3.10) for the 0-14-year olds to 6.36 (95% CI: 5.83, 6.90) in the 25-34-year-old group. CONCLUSION: There are large age-group and regional differences in CHB prevalence in Turkey, where CHB remains a serious health problem

    Outcomes from elective colorectal cancer surgery during the SARS-CoV-2 pandemic

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    This study aimed to describe the change in surgical practice and the impact of SARS-CoV-2 on mortality after surgical resection of colorectal cancer during the initial phases of the SARS-CoV-2 pandemic

    Elective cancer surgery in COVID-19-free surgical pathways during the SARS-CoV-2 pandemic: An international, multicenter, comparative cohort study

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    PURPOSE As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether COVID-19–free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway. PATIENTS AND METHODS This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19–free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation). RESULTS Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19–free surgical pathways. Patients who underwent surgery within COVID-19–free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19–free surgical pathways (2.2% v 4.9%; adjusted odds ratio [aOR], 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score–matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19–free surgical pathways (2.1% v 3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76). CONCLUSION Within available resources, dedicated COVID-19–free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks

    Elective Cancer Surgery in COVID-19-Free Surgical Pathways During the SARS-CoV-2 Pandemic: An International, Multicenter, Comparative Cohort Study.

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    PURPOSE: As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether COVID-19-free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway. PATIENTS AND METHODS: This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19-free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation). RESULTS: Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19-free surgical pathways. Patients who underwent surgery within COVID-19-free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19-free surgical pathways (2.2% v 4.9%; adjusted odds ratio [aOR], 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score-matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19-free surgical pathways (2.1% v 3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76). CONCLUSION: Within available resources, dedicated COVID-19-free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks
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