RESUMEN
In order to enhance the overall efficiency of colloidal quantum dots solar cells, it is crucial to suppress the recombination of charge carriers and minimize energy loss at the interfaces between the transparent electrode, electron transport layer (ETL), and colloidal quantum dots (CQDs) light-absorbing material. In the current study, ZnO/SrTiO3 (STO), ZnO/WO3 (TO), and ZnO/Zn2SnO4 (ZTO) bilayers are introduced as an ETL using a spin-coating technique. The ZTO interlayer exhibits a smoother surface with a root-mean-square (RMS) value of ≈ 3.28 nm compared to STO and TO interlayers, which enables it to cover the surface of the ITO/ZnO substrate entirely and helps to prevent direct contact between the CQDs absorber layer and the ITO/ZnO substrate, thereby effectively preventing efficient charge recombination at the interfaces of the ETL/CQDs. Furthermore, the ZTO interlayer possesses superior electron mobility, a higher visible light transmission, and a suitable energy band structure compared to STO and TO. These characteristics are advantageous for extracting charge carriers and facilitating electron transport. The PbS CQDs solar cell based on the ITO/ZnO/ZTO/PbS-FABr/PbS-EDT/NiO/Au device configuration exhibits the highest efficiency of 15.28%, which is significantly superior than the ITO/ZnO/PbS-FABr/PbS-EDT/NiO/Au solar cell device (PCE = 14.38%). This study is anticipated to offer a practical approach to develop ultrathin and compact ETL for highly efficient CQDSCs.
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The majority of meniscal tears in bucket handles are associated with anterior cruciate ligament (ACL) impairment. Its a rare condition which is rarely encountered when the meniscus has a bucket handle on both sides of the compartment. Here we present the case of a 28-year- old male cricket player with a total ACL rupture, a double Posterior Cruciate ligament (PCL) sign on MRI (Magnetic Resonance Imaging), an uncommon occurrence of a complex bucket handle rupture of the medial meniscus with a double PCL sign. It was a complete ACL tear and displaced bucket handle medial meniscus that was also visible on the magnetic resonance imaging. In this report, double PCL sign was shown on MRI and that was confirmed during the arthroscopic procedure.
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Lesiones del Ligamento Cruzado Anterior , Traumatismos de la Rodilla , Lesiones de Menisco Tibial , Humanos , Masculino , Adulto , Lesiones del Ligamento Cruzado Anterior/diagnóstico por imagen , Lesiones del Ligamento Cruzado Anterior/cirugía , Lesiones del Ligamento Cruzado Anterior/complicaciones , Artroscopía/métodos , Ligamento Cruzado Anterior/cirugía , Meniscos Tibiales/patología , Meniscos Tibiales/cirugía , Traumatismos de la Rodilla/cirugía , Lesiones de Menisco Tibial/diagnóstico por imagen , Lesiones de Menisco Tibial/cirugía , Lesiones de Menisco Tibial/complicaciones , Imagen por Resonancia Magnética/métodos , Estudios RetrospectivosRESUMEN
Congenital muscular torticollis is a problem that arises at birth or immediately after birth in which the sternocleidomastoid muscle is shortened on the afflicted side, leading to an ipsilateral rotated of the head and a contralateral rotation of the face and jaw. To determine the effectiveness of physical therapy treatment in infants treated for congenital muscular torticollis, relevant articles published between 2011 and 2020 were located using electronic databases. A total of 9 studies out of 24 potentially relevant articles were reviewed. All studies were randomised controlled trials with 6-8 score on the Physiotherapy Evidence Database scale (Pedro scale) which showed high quality of methodology. The studies typically found significant statistical effects in the management of congenital muscular torticollis. Additionally, most of the studies reported increased adherence to exercise as another essential advantage. Conservative physical therapy management showed positive outcomes, and early physiotherapy referral showed significant reduction in treatment duration.
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Fibroma , Enfermedades Musculares , Tortícolis , Recién Nacido , Lactante , Humanos , Tortícolis/terapia , Tortícolis/congénito , Músculos del Cuello , Modalidades de FisioterapiaRESUMEN
As the pandemic made it unsafe for providers and patients to meet in person, the US government implemented key temporary telehealth waivers in March 2020 that expanded Medicare telehealth coverage dramatically. Some of the most significant changes included the removal of location restrictions so that patients and providers could engage in telehealth from their homes, full provider reimbursement for telehealth visits, coverage for more medical specialties and types of practitioners such as occupational and physical therapists, and the allowance of telehealth prescription of controlled substances. The waivers will end when the government removes the federal status of a public health emergency, which is expected to occur in 2023. Nearly 64 million Medicare patients are at risk of losing most modalities of telehealth access. We present current legislation that could combat this "telehealth cliff" and defend the position that Medicare telehealth access should remain permanently expanded.
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The intricate problems concerning energy require innovative solutions. Herein, we propose a smart composite nano system that can be used in a sustainable and dichotomous manner to resolve energy crises. The current study describes a new way to synthesize a pure spinel cobalt oxide (Co3O4) and boron (B), nitrogen (N), and sulfur (S) tri-doped Co3O4-reduced graphite oxide (rGO) nanocomposite (CBNS). A hydrothermal method has been used for the synthesis of these nanomaterials. The synthesized nanocomposite was characterized by UV-visible spectroscopy, X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), X-ray absorption spectroscopy (XAS), and transmission electron microscopy (TEM). The XRD results showed the formation of Co3O4 and B, N, S doped nanocomposite with high purity and crystallinity. XAS analysis elucidates the formation of spinel Co3O4 with tetrahedral and octahedral arrangement of cobalt ions. The peaks at 2.50 Å and 3.07 Å are due to the Co-Co bonding. The electrocatalytic oxygen reduction (ORR) was successfully implemented using these nanocomposites. The electrochemical study exhibits the better activity of the B, N, and S tri-doped Co3O4-rGO nanocomposite due to the mutual effect of B, N and S. The synthesized catalyst has maximum current density of 9.97 mA cm-2 with onset potential (Eonset) of 0.98 V in alkaline medium.
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Student mental health concerns can manifest in several forms. Medical students juggling a multitude of trials (i.e., intense academic rigor, financial debt, sleep deprivation, lack of control, continual exposure to sickness and death, and training mistreatment) can help explain the higher prevalence of psychological disorders within this population. Furthermore, these mental health difficulties are not static; certain challenges move into the forefront as students face key transition points in schooling. Primary examples include the entry year of medical school, the shift from preclinical curriculum to clinical training, and the final moments prior to beginning residency. Given the existing mental health trends among medical students at baseline, it can be concluded that the COVID-19 pandemic has exacerbated the stress, anxiety, and depression associated with medical education. Solutions do indeed exist to address the moral injury medical students face, from expanded crisis management training and implementation of peer support networks to destigmatization of and improved access to professional mental health resources. It is up to the curators of the medical education system to make these solutions the new status quo.
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In order to assess the metal pollution status of agricultural lands of Mandi Bahauuddin receiving industrial wastewater, 35 top soil samples were investigated for the determination of selected metal levels, i.e., Fe, Cu, Cd, Cr, Ca, Ni, and Pb by flame atomic absorption spectroscopy under optimum analytical conditions. The distribution of these metals in different operationally defined chemical fractions was also determined by using the sequential extraction technique. The highest mean total concentration was found for Fe while the least one was observed for Pb. All the studied metals were found to be present at levels much enhanced than national and international standards. Moreover, most of the metals were distributed principally in residual fraction with the exception of Ni which was found to be associated mainly with oxidizable fraction. The significant correlations were observed between Fe-Mn oxide-bound and residual fractions and exchangeable and oxidizable fractions for most of the metals. The highest mobility was exhibited by Ni that evidenced its enhanced bioavailability in the soil. The multivariate statistical analyses in terms of principal component analysis (PCA) and cluster analysis (CA) revealed multiple sources for various geochemical fractions of different metals. CA also revealed that the nonresidual fractions of most of the metals were very closely associated while PCA presented a distinctive behavior of Ca in the soil. It was therefore suggested that in order to avoid the metal contamination arising from industrial wastewater, appropriate remediation strategies must be adopted.
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Contaminación Ambiental/estadística & datos numéricos , Metales/análisis , Contaminantes del Suelo/análisis , Suelo/química , Eliminación de Residuos Líquidos/métodos , Agricultura , Análisis por Conglomerados , Monitoreo del Ambiente , Residuos Industriales/análisis , Residuos Industriales/estadística & datos numéricos , Modelos Químicos , Análisis de Componente PrincipalRESUMEN
Colloidal quantum dot solar cells (CQDSCs) have achieved remarkable progress recently in terms of mainly surface passivation and composition-matching matrices on CQDs, while improving the overall photoelectric conversion efficiency (PCE) through electron transport layer (ETL) modifications is less explored. We report a low-temperature solution route to synthesize donor (Al3+/Ga3+/In3+) incorporated zinc oxide (AZO/GZO/IZO) ETL films for PbS CQDSCs. Spectroscopic characterization studies indicate that the IZO ETL fabricated with 150 °C annealing can increase the bandgap the most from 3.56 eV to 3.74 eV, possesses enhanced light transmission (â¼94%) and finer particle sizes, and importantly shows the most suitable band alignment and charge transfer ability. Well-dispersed PbS CQDs of around 3 nm are synthesized by a N2-protected reflux method and are surface exchanged with 1-ethyl-3-methylimidazolium iodide (EMII) to allow I- grafting and ethanedithiol (EDT) for the active layer and hole transport layer, respectively. The IZO based PbS CQDSC, with a device architecture of ITO/IZO/PbS-EMII/PbS-EDT/Au, shows an enhanced PCE of 11.1% (comparatively 18% higher than that of the ZnO ETL), a VOC value of 0.64 V, and a JSC of 25.8 mA cm-2. The improved performances benefit from the higher recombination resistance and constrained photoluminescence emission with the utilization of the IZO ETL that provides a superior charge transfer property.
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Chemical phosphorus removal (CPR) is being increasingly adopted in wastewater treatment plants (WWTPs) to enhance P elimination to comply with stringent discharge limits. However, strategies to recover P enriched in the produced waste activated sludge (WAS) are not well developed. In this study, we investigated the release of P in WAS from three WWTPs employing Al salt enhanced CPR by alkaline treatment. We also monitored P mobilization by tracking the dynamics of P fractions and species, the dissolution of major metals, and sludge cell integrities as pH was altered. The level of aqueous total phosphorus (TPaq) in the sludge increased significantly to >200â¯mg/L (from <11â¯mg/L in the raw sludge) as the pH was increased to 12, with the majority being PO4-Paq especially at high pHs. The dominance of non-apatite inorganic phosphorus (NAIP) in the sludge-P, a good correlation observed between aqueous PO4-P and aqueous Al, and the reversibility of P mobilization all suggest that the dissolution of Al-bound P was largely responsible for the sludge-P release. Sludge cell integrity, on the other hand, was not closely correlated with TPaq concentrations. Although the level of TP released in this study is among the highest, a more efficient strategy still needs to be developed to further enhance sludge-P release when TP content in the sludge mixture (TPmx) is considered (TPmx was >800â¯mg/L in this work).
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Fósforo/química , Eliminación de Residuos Líquidos/métodos , Contaminantes del Agua/química , Aluminio/química , Fósforo/análisis , Contaminantes del Agua/análisisRESUMEN
Carbon based perovskite solar cells (PSCs) are fabricated through easily scalable screen printing techniques, using abundant and cheap carbon to replace the hole transport material (HTM) and the gold electrode further reduces costs, and carbon acts as a moisture repellent that helps in maintaining the stability of the underlying perovskite active layer. An inorganic interlayer of spinel cobaltite oxides (Co3O4) can greatly enhance the carbon based PSC performance by suppressing charge recombination and extracting holes efficiently. The main focus of this research work is to investigate the effectiveness of Co3O4 spinel oxide as the hole transporting interlayer for carbon based perovskite solar cells (PSCs). In these types of PSCs, the power conversion efficiency (PCE) is restricted by the charge carrier transport and recombination processes at the carbon-perovskite interface. The spinel Co3O4 nanoparticles are synthesized using the chemical precipitation method, and characterized by X-ray diffraction (XRD), X-ray absorption spectroscopy (XAS), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and UV-Vis spectroscopy. A screen printed thin layer of p-type inorganic spinel Co3O4 in carbon PSCs provides a better-energy level matching, superior efficiency, and stability. Compared to standard carbon PSCs (PCE of 11.25%) an improved PCE of 13.27% with long-term stability, up to 2500 hours under ambient conditions, is achieved. Finally, the fabrication of a monolithic perovskite module is demonstrated, having an active area of 70 cm2 and showing a power conversion efficiency of >11% with virtually no hysteresis. This indicates that Co3O4 is a promising interlayer for efficient and stable large area carbon PSCs.