39 research outputs found
New constraints from U–Pb dating of detrital zircons on the palaeogeographic origin of metasediments in the Talea Ori, central Crete
High-pressure low-temperature metamorphic sediments of the Phyllite–Quartzite unit sensu stricto and the Talea Ori group are investigated in the field, microstructurally and by U–Pb dating of detrital zircons to shed light on their palaeogeographic origin. Zircon age spectra with ages >450 Ma of the Phyllite–Quartzite unit sensu stricto indicate a palaeogeographic origin at the northern margin of East Gondwana. In contrast, the lower stratigraphic, siliciclastic formations of the Talea Ori group show a high number of well-rounded Cambrian to Early Carboniferous aged zircons and a Neoproterozoic zircon age spectrum with East Gondwana affinity. Based on the comparison of zircon age data, a possible distal sediment source is the Sakarya Zone at the southern active margin of Eurasia. To reconcile the zircon data with the geological observations we propose different alternative models, or a combination of these, including sediment transport from the Sakarya Zone and/or a westerly source towards the northern margin of Gondwana as well as terrane-displacement of the Sakarya Zone. Also, a palaeogeographic origin of the Talea Ori group at the southern active margin of Eurasia cannot be excluded. This alternative, however, would not be consistent with the usually assumed association of the Talea Ori group with the Plattenkalk unit characterized by a palaeogeographic origin at the northern margin of Gondwana
Chemical in‐depth analysis of (Ca/Sr)F2 core–shell like nanoparticles by X‐ray photoelectron spectroscopy with tunable excitation energy
The fluorolytic sol–gel synthesis is applied with the intention to obtain two different types of core–shell nanoparticles, namely, SrF2–CaF2 and CaF2–SrF2. In two separate fluorination steps for core and shell formation, the corresponding metal lactates are reacted with anhydrous HF in ethylene glycol. Scanning transmission electron microscopy (STEM) and dynamic light scattering (DLS) confirm the formation of particles with mean dimensions between 6.4 and 11.5 nm. The overall chemical composition of the particles during the different reaction steps is monitored by quantitative Al Kα excitation X-ray photoelectron spectroscopy (XPS). Here, the formation of stoichiometric metal fluorides (MF2) is confirmed, both for the core and the final core–shell particles. Furthermore, an in-depth analysis by synchrotron radiation XPS (SR-XPS) with tunable excitation energy is performed to confirm the core–shell character of the nanoparticles. Additionally, Ca2p/Sr3d XPS intensity ratio in-depth profiles are simulated using the software Simulation of Electron Spectra for Surface Analysis (SESSA). In principle, core–shell like particle morphologies are formed but without a sharp interface between calcium and strontium containing phases. Surprisingly, the in-depth chemical distribution of the two types of nanoparticles is equal within the error of the experiment. Both comprise a SrF2-rich core domain and CaF2-rich shell domain with an intermixing zone between them. Consequently, the internal morphology of the final nanoparticles seems to be independent from the synthesis chronology.European Metrology Programme for Innovation and Research (EMPIR)
http://dx.doi.org/10.13039/100014132Peer Reviewe
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Chemical in-depth analysis of (Ca/Sr)F2 core–shell like nanoparticles by X-ray photoelectron spectroscopy with tunable excitation energy
The fluorolytic sol–gel synthesis is applied with the intention to obtain two different types of core–shell nanoparticles, namely, SrF2–CaF2 and CaF2–SrF2. In two separate fluorination steps for core and shell formation, the corresponding metal lactates are reacted with anhydrous HF in ethylene glycol. Scanning transmission electron microscopy (STEM) and dynamic light scattering (DLS) confirm the formation of particles with mean dimensions between 6.4 and 11.5 nm. The overall chemical composition of the particles during the different reaction steps is monitored by quantitative Al Kα excitation X-ray photoelectron spectroscopy (XPS). Here, the formation of stoichiometric metal fluorides (MF2) is confirmed, both for the core and the final core–shell particles. Furthermore, an in-depth analysis by synchrotron radiation XPS (SR-XPS) with tunable excitation energy is performed to confirm the core–shell character of the nanoparticles. Additionally, Ca2p/Sr3d XPS intensity ratio in-depth profiles are simulated using the software Simulation of Electron Spectra for Surface Analysis (SESSA). In principle, core–shell like particle morphologies are formed but without a sharp interface between calcium and strontium containing phases. Surprisingly, the in-depth chemical distribution of the two types of nanoparticles is equal within the error of the experiment. Both comprise a SrF2-rich core domain and CaF2-rich shell domain with an intermixing zone between them. Consequently, the internal morphology of the final nanoparticles seems to be independent from the synthesis chronology
Substance use disorders and adherence to antituberculosis medications in Southwest Ethiopia: a prospective cohort study
Objectives .In Ethiopia, little is known about the association between substance use disorders and adherence to antituberculosis (anti-TB) medications. Therefore, the objective of this study was to assess the effect of substance use disorders on adherence to anti-TB medications in Southwest Ethiopia.
Design. Prospective cohort study.
Settings. Patients were recruited from 22 health centres and four hospitals in Southwest Ethiopia.
Participants. This study was conducted among 268 patients with TB, aged 18–80 in Southwest Ethiopia between October 2017 and October 2018. At baseline, patients who were exposed substance use disorders (134 patients) and unexposed to substance use disorders (134 patients) were recruited. Patients were followed for 6 months, and data were collected on three occasions.
Main outcome measure. Adherence to anti-TB medications.
Results. Patients with substance use disorders had consistently higher prevalence of non-adherence than those without, 16.4% versus 3.0% at baseline, 41.7% versus 14.4% at 2-month follow-up and 45.7% versus 10.8% at 6-month follow-up assessments. Patients with khat use disorder were 3.8 times more likely to be non-adherent to anti-TB medications than patients without khat use disorder (Adjusted odds ratio (aOR)=3.8, 95% CI 1.8 to 8.0). Patients who had alcohol use disorder (AUD) were also 3.2 times likely to have poor adherence compared with their counterparts (aOR=3.2, 95% CI 1.6 to 6.6). In addition, being educated (aOR=4.4, 95% CI 1.7 to 11.3), and being merchant (aOR=6.1, 95% CI 1.2 to 30.8) were associated with non-adherence to anti-TB medications.
Conclusion. Khat and AUDs predict greater likelihood of non-adherence to anti-TB medication. This implies the need to integrate the management for substance use disorders into the existing TB treatment services
Magnitude and predictors of khat use among patients with tuberculosis in Southwest Ethiopia: A longitudinal study
INTRODUCTION Tuberculosis (TB) is a leading cause of morbidity and mortality in low and middle-income countries. Substance use negatively affects TB treatment outcomes. Our recent study has found that khat use predicted poorer adherence to anti-TB medications. However, there is scarce longitudinal study on predictors of khat use among outpatients with TB, and this study aimed at addressing this research gap. METHODS From October 2017 to October 2018, 268 outpatients with tuberculosis on DOTs were enrolled in a longitudinal study from 26 health institutions in Southwest Ethiopia. Structured questionnaires translated into local languages (Afaan Oromoo and Amharic) were used to assess khat use. Patients were followed for six months, and data were collected on three occasions during the follow-up. A generalized linear mixed model was used to identify the relation between khat use and predictors. Model fitness was checked using the Bayesian Information Criterion (BIC). Odds ratio (OR) and 95% CI were used to describe the strength of association between the outcome variable and predictors. RESULTS The overall prevalence of khat use at baseline and first follow up was 39.2% while it was 37.3% at second follow up. Of this, 77.1% and 96.2% of them believed that khat use reduces the side effects of anti-TB medications and symptoms of tuberculosis respectively. In the final model, being male (aOR = 7.0, p-value = 0.001), being government employee (aOR = 0.03, p-value≤0.001) and presence of alcohol use disorders (AUD) (aOR = 2.0, p-value≤0.001) predicted khat use among outpatients with tuberculosis. CONCLUSION A considerable proportion of patients with TB used khat throughout DOTs and wrongly perceived that it had health benefits. The finding implies that all patients diagnosed with TB should be screened for khat use, and a particular emphasis should be given to males and individuals with a history of alcohol use. Moreover, further studies are needed to assess patients' beliefs regarding the benefits of khat use so that interventions can be developed
Mental distress and associated factors among undergraduate students at the University of Hargeisa, Somaliland: a cross-sectional study
Background: Mental distress is a common finding among University students. Empirical research has confirmed that the University student population has a higher prevalence of mental disorder than the general population. However, no previous study has examined the mental health conditions of students in Somaliland. Methods: An institution based cross-sectional study was conducted on a sample of 570 undergraduate students at the University of Hargeisa in October, 2013. Study subjects were selected using a stratified random sampling. The Self-reporting questionnaire (SRQ-20) was used to assess mental distress. Multiple logistic regression analysis was carried out to identify factors independently associated with mental distress. Results: The point prevalence of mental distress was found to be 19.8%. Mental distress was associated with being female (AOR = 3.52, 95% CI 1.94, 6.39), having a monthly income of 100 United States dollars (USD) or less (AOR = 2.19, 95% CI 1.12, 4.28), and not having a satisfying relationship with the family (AOR = 11.52, 95% CI 3.18, 41.72) and friends (AOR = 7.33, 95% CI 2.83, 18.93). Nearly one in five students (18.6%) has been using Khat in the previous 12 months. Khat use was also associated with greater likelihood of mental distress (AOR = 2.87, 95% CI 1.26, 6.56). In addition, financial difficulties and the poor prospect of finding a job were common sources of stress among the students. Conclusions: A significant proportion of the students at the University of Hargeisa suffer from mental distress which might have a detrimental effect on their academic performance. The mental health needs of the University students require attention with special emphasis on female students, students experiencing financial hardships, students who use Khat and those who have interpersonal problems
Hip joint load and muscle stress in soccer inside passing
Studies investigating the mechanisms of adductor injuries in soccer have concentrated on full effort kicks. Purpose of this study was a kinetic analysis of the inside pass. Using infrared cameras and inverse dynamics, hip joint moments and adductor muscle stress was calculated during the swing phase of the pass. Moments in the transverse plane were nearly as high as in full effort kicks reported previously. Muscle stress in the m. gracilis reached up to 450 kPa. Considering the repetitive nature of inside passes in modern sot; cer, adductor muscles undergo high loads in matches and training. This might contribute to the explanation of the high incidences of adductor injuries. Practitioners should therefore consider the load-recovery-relation even in inside pass training. Specific strength training programs for the adductor and abductor muscle groups should be developed
HIP JOINT LOAD AND MUSCLE STRESS IN SOCCER INSIDE PASSlNG
Studies investigating the mechanisms of adductor injuries in soccer have concentrated on full effort kicks. Purpose of this study was a kinetic analysis of the inside pass. Using infrared cameras and inverse dynamics, hip joint moments and adductor muscle stress was calculated during the swing phase of the pass. Moments in the transverse plane were nearly as high as in full effort kicks reported previously. Muscle stress in the m. gracilis reached up to 450 kPa. Considering the repetitive nature of inside passes in modern sot; cer, adductor muscles undergo high loads in matches and training. This might contribute to the explanation of the high incidences of adductor injuries. Practitioners should therefore consider the load-recovery-relation even in inside pass training. Specific strength training programs for the adductor and abductor muscle groups should be developed