Električna i preklopna svojstva tankih amorfnih slojeva ZnIn2Se4

In this work electrical and switching properties of amorphous ZnIn2Se4 thin films have been studied. The amorphous films were obtained by thermal evaporation in vacuum, of polycrystalline materials, on glass or pyrographite substrates. From electrical measurements, it was found that for all films the dark electrical resistivity decreases with an increase of film thickness and temperature. The ZnIn2Se4 films exhibit nonlinear I-V characteristics and switching phenomena. The threshold voltage decreases with increasing temperature and increases with increasing film thickness.Istraživala su se električna i preklopna svojstva tankih amorfnih slojeva ZnIn2Se4. Amorfni su slojevi pripremljeni naparavanjem polikristaliničnih materijala na staklene ili pirografitne podloge u vakuumu. Električna mjerenja pokazuju da se za sve slojeve električni otpor u tami smanjuje s povećanjem debljine sloja i temperature. Slojevi ZnIn2Se4 pokazuju nelinearnu ovisnost I − V i preklopna svojstva. Napon praga preklopa smanjuje se s povećanjem temperature i povećava za veće debljine slojeva

Električna i preklopna svojstva tankih amorfnih slojeva ZnIn2Se4

In this work electrical and switching properties of amorphous ZnIn2Se4 thin films have been studied. The amorphous films were obtained by thermal evaporation in vacuum, of polycrystalline materials, on glass or pyrographite substrates. From electrical measurements, it was found that for all films the dark electrical resistivity decreases with an increase of film thickness and temperature. The ZnIn2Se4 films exhibit nonlinear I-V characteristics and switching phenomena. The threshold voltage decreases with increasing temperature and increases with increasing film thickness.Istraživala su se električna i preklopna svojstva tankih amorfnih slojeva ZnIn2Se4. Amorfni su slojevi pripremljeni naparavanjem polikristaliničnih materijala na staklene ili pirografitne podloge u vakuumu. Električna mjerenja pokazuju da se za sve slojeve električni otpor u tami smanjuje s povećanjem debljine sloja i temperature. Slojevi ZnIn2Se4 pokazuju nelinearnu ovisnost I − V i preklopna svojstva. Napon praga preklopa smanjuje se s povećanjem temperature i povećava za veće debljine slojeva

Knowledge and Practice of PHC Physicians toward the Detection and Management of Hypertension and Other CVD Risk Factors in Egypt

Aim. To assess the knowledge and practice of PHC physicians toward the detection and management of hypertension (HTN) and other CVD risk factors. Methods. A cross-sectional study of all primary health care physicians of the FHU of three rural districts of Egypt was conducted. Each physician was subjected to a prevalidated interview questionnaire on the WHO-CVD risk management package for low and medium resources, and a checklist of observation of daily practices. Results. Hypertension was a priority problem in about two-thirds (62.9%) of physicians, yet only 19% have guidelines for HTN patients. Clinical history recording system for HNT was available for 50% of physicians. Levels of knowledge varied with regard to definition of HTN (61.3%, fair), procedures for BP measurement (43.5%, poor), indications for referral (43.5%, poor), patient counseling (61.3%, fair), patient treatment (59.8%, fair). Availability of clinical history recording system for HNT was a significant predictor for physician's level of knowledge (P = 0.001). Overall level of practice was fair (68.5%). Conclusion. PHC physicians have unsatisfactory knowledge and practice on hypertension. There is a need of more continuing medical education. Local and international manuals, workshops, and seminars on how to make use of these guidelines would improve doctors' performance

Strukturna i električna svojstva tankih slojeva kalkogenida CuSbTe2, CuSbSe2 i CuSbS2

The ternary chalcogenides CuSbTe2, CuSbSe2 and CuSbS2 were synthesized by the direct fusion technique. The thin films of these compounds were prepared by thermal evaporation under vacuum of about 1.3 mPa (10−5 Torr) and the rate of deposition was 30 nm/min. The structural properties of CuSbTe2, CuSbSe2 and CuSbS2 in powder and thin film forms were investigated by X-ray diffraction (XRD) and transmission electronmicroscopy. Microprobe analysis technique was used to investigate the composition of the three alloys and of their films. The electrical conductivity σ and the thermoelectrical power Q have been measured for all asdeposited and annealed thin films, as a function of temperature in the range from 80 to 500 K. It was found that the electrical conductivity σ, the carrier concentration P, the mobility µ and the thermoelectric power Q increase when increasing the annealing temperature for CuSbTe2, CuSbSe2 and CuSbS2 thin films. The increase of σ, P, µ and Q, and also the decrease of the activation energy ∆E with increasing temperature for the as-deposited CuSbTe2, CuSbSe2 and CuSbS2 thin films, can be attributed to the change in the structure of these films from the amorphous to the crystalline state.Trokomponentne smo kalkogenide CuSbTe2, CuSbSe2 and CuSbS2 pripremili metodom talenja. Tanke smo slojeve tih spojeva pripremali isparavanjem u vakuumu od oko 1.3 mPa, brzinom nanošenja oko 30 nm/min. Strukturna svojstva tih kalkogenida, kako praškova, tako i tankih slojeva, istraživali smo difrakcijom rendgenskog zračenja i prolaznom elektronskom mikroskopijom. Pomoću mikroprobe odredili smo kemijski sastav spojeva i njihovih tankih slojeva. Izmjerili smo električnu vodljivost, σ, i termoelektričnu snagu, Q, svih svježe naparenih i opuštenih legura i njihovih tankih slojeva u ovisnosti o temperaturi u području 80 do 500 K. Električna vodljivost, gustoća nositelja, P, mobilnost, µ, i termoelektrična snaga, Q, povećavaju se ako se tanki slojevi opuštaju na višim temperaturama. Povećanje σ, P, µ and Q, a također smanjenje aktivacijske energije, ∆E, u tankim slojevima CuSbTe2, CuSbSe2 i CuSbS2 tumače se promjenama strukture tih slojeva od amorfnog u kristalinično stanje

Strukturna i električna svojstva tankih slojeva kalkogenida CuSbTe2, CuSbSe2 i CuSbS2

The ternary chalcogenides CuSbTe2, CuSbSe2 and CuSbS2 were synthesized by the direct fusion technique. The thin films of these compounds were prepared by thermal evaporation under vacuum of about 1.3 mPa (10−5 Torr) and the rate of deposition was 30 nm/min. The structural properties of CuSbTe2, CuSbSe2 and CuSbS2 in powder and thin film forms were investigated by X-ray diffraction (XRD) and transmission electronmicroscopy. Microprobe analysis technique was used to investigate the composition of the three alloys and of their films. The electrical conductivity σ and the thermoelectrical power Q have been measured for all asdeposited and annealed thin films, as a function of temperature in the range from 80 to 500 K. It was found that the electrical conductivity σ, the carrier concentration P, the mobility µ and the thermoelectric power Q increase when increasing the annealing temperature for CuSbTe2, CuSbSe2 and CuSbS2 thin films. The increase of σ, P, µ and Q, and also the decrease of the activation energy ∆E with increasing temperature for the as-deposited CuSbTe2, CuSbSe2 and CuSbS2 thin films, can be attributed to the change in the structure of these films from the amorphous to the crystalline state.Trokomponentne smo kalkogenide CuSbTe2, CuSbSe2 and CuSbS2 pripremili metodom talenja. Tanke smo slojeve tih spojeva pripremali isparavanjem u vakuumu od oko 1.3 mPa, brzinom nanošenja oko 30 nm/min. Strukturna svojstva tih kalkogenida, kako praškova, tako i tankih slojeva, istraživali smo difrakcijom rendgenskog zračenja i prolaznom elektronskom mikroskopijom. Pomoću mikroprobe odredili smo kemijski sastav spojeva i njihovih tankih slojeva. Izmjerili smo električnu vodljivost, σ, i termoelektričnu snagu, Q, svih svježe naparenih i opuštenih legura i njihovih tankih slojeva u ovisnosti o temperaturi u području 80 do 500 K. Električna vodljivost, gustoća nositelja, P, mobilnost, µ, i termoelektrična snaga, Q, povećavaju se ako se tanki slojevi opuštaju na višim temperaturama. Povećanje σ, P, µ and Q, a također smanjenje aktivacijske energije, ∆E, u tankim slojevima CuSbTe2, CuSbSe2 i CuSbS2 tumače se promjenama strukture tih slojeva od amorfnog u kristalinično stanje

Characterization of greater middle eastern genetic variation for enhanced disease gene discovery

The Greater Middle East (GME) has been a central hub of human migration and population admixture. The tradition of consanguinity, variably practiced in the Persian Gulf region, North Africa, and Central Asia1-3, has resulted in an elevated burden of recessive disease4. Here we generated a whole-exome GME variome from 1,111 unrelated subjects. We detected substantial diversity and admixture in continental and subregional populations, corresponding to several ancient founder populations with little evidence of bottlenecks. Measured consanguinity rates were an order of magnitude above those in other sampled populations, and the GME population exhibited an increased burden of runs of homozygosity (ROHs) but showed no evidence for reduced burden of deleterious variation due to classically theorized ‘genetic purging’. Applying this database to unsolved recessive conditions in the GME population reduced the number of potential disease-causing variants by four- to sevenfold. These results show variegated genetic architecture in GME populations and support future human genetic discoveries in Mendelian and population genetics

Addressing climate change with behavioral science: a global intervention tournament in 63 countries

Effectively reducing climate change requires marked, global behavior change. However, it is unclear which strategies are most likely to motivate people to change their climate beliefs and behaviors. Here, we tested 11 expert-crowdsourced interventions on four climate mitigation outcomes: beliefs, policy support, information sharing intention, and an effortful tree-planting behavioral task. Across 59,440 participants from 63 countries, the interventions’ effectiveness was small, largely limited to nonclimate skeptics, and differed across outcomes: Beliefs were strengthened mostly by decreasing psychological distance (by 2.3%), policy support by writing a letter to a future-generation member (2.6%), information sharing by negative emotion induction (12.1%), and no intervention increased the more effortful behavior—several interventions even reduced tree planting. Last, the effects of each intervention differed depending on people’s initial climate beliefs. These findings suggest that the impact of behavioral climate interventions varies across audiences and target behaviors

Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries

Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P < 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century