Bandgap-universal passivation enables stable perovskite solar cells with low photovoltage loss

The efficiency and longevity of metal-halide perovskite solar cells are typically dictated by nonradiative defect-mediated charge recombination. In this work, we demonstrate a vapor-based amino-silane passivation that reduces photovoltage deficits to around 100 millivolts (>90% of the thermodynamic limit) in perovskite solar cells of bandgaps between 1.6 and 1.8 electron volts, which is crucial for tandem applications. A primary-, secondary-, or tertiary-amino-silane alone negatively or barely affected perovskite crystallinity and charge transport, but amino-silanes that incorporate primary and secondary amines yield up to a 60-fold increase in photoluminescence quantum yield and preserve long-range conduction. Amino-silane-treated devices retained 95% power conversion efficiency for more than 1500 hours under full-spectrum sunlight at 85°C and open-circuit conditions in ambient air with a relative humidity of 50 to 60%.

Phase segregation and nanoconfined fluid O2 in a lithium-rich oxide cathode

Lithium-rich oxide cathodes lose energy density during cycling due to atomic disordering and nanoscale structural rearrangements, which are both challenging to characterize. Here we resolve the kinetics and thermodynamics of these processes in an exemplar layered Li-rich (Li1.2-xMn0.8O2) cathode using a combined approach of ab initio molecular dynamics and cluster expansion-based Monte Carlo simulations. We identify a kinetically accessible and thermodynamically favourable mechanism to form O2 molecules in the bulk, involving Mn migration and driven by interlayer oxygen dimerization. At the top of charge, the bulk structure locally phase segregates into MnO2-rich regions and Mn-deficient nanovoids, which contain O2 molecules as a nanoconfined fluid. These nanovoids are connected in a percolating network, potentially allowing long-range oxygen transport and linking bulk O2 formation to surface O2 loss. These insights highlight the importance of developing strategies to kinetically stabilize the bulk structure of Li-rich O-redox cathodes to maintain their high energy densities.

Emergence of Long-Range Angular Correlations in Low-Multiplicity Proton-Proton Collisions

This Letter presents the measurement of near-side associated per-trigger yields, denoted ridge yields, from the analysis of angular correlations of charged hadrons in proton-proton collisions at sqrt[s]=13  TeV. Long-range ridge yields are extracted for pairs of charged particles with a pseudorapidity difference of 1.4<|Δη|<1.8 and a transverse momentum of 1 Collapse

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First Measurement of the |t| Dependence of Incoherent J/ψ Photonuclear Production

The first measurement of the cross section for incoherent photonuclear production of J/ψ vector mesons as a function of the Mandelstam |t| variable is presented. The measurement was carried out with the ALICE detector at midrapidity, |y|<0.8, using ultraperipheral collisions of Pb nuclei at a center-of-mass energy per nucleon pair of sqrt[s_{NN}]=5.02  TeV. This rapidity interval corresponds to a Bjorken-x range (0.3-1.4)×10^{-3}. Cross sections are given in five |t| intervals in the range 0.04<|t|<1  GeV^{2} and compared to the predictions by different models. Models that ignore quantum fluctuations of the gluon density in the colliding hadron predict a |t| dependence of the cross section much steeper than in data. The inclusion of such fluctuations in the same models provides a better description of the data.

Global cross-cultural validation of a brief measure for identifying potential suicide risk in 42 countries

OBJECTIVES

This study aimed to examine the psychometric properties of the P4 suicide screener in a multinational sample. The primary goal was to evaluate the reliability and validity of the scale and investigate its convergent validity by analyzing its correlation with depression, anxiety, and substance use.

STUDY DESIGN

The study design is a cross-sectional self-report study conducted across 42 countries.

METHODS

A cross-sectional, self-report study was conducted in 42 countries, with a total of 82,243 participants included in the final data set.

RESULTS

The study provides an overview of suicide ideation rates across 42 countries and confirms the structural validity of the P4 screener. The findings indicated that sexual and gender minority individuals exhibited higher rates of suicidal ideation. The P4 screener showed adequate reliability, convergence, and discriminant validity, and a cutoff score of 1 is recommended to identify individuals at risk of suicidal behavior.

CONCLUSIONS

The study supports the reliability and validity of the P4 suicide screener across 42 diverse countries, highlighting the importance of using a cross-cultural suicide risk assessment to standardize the identification of high-risk individuals and tailoring culturally sensitive suicide prevention strategies.

Effect of gamma (γ-) radiation on the opto-structural and morphological properties of green synthesized BaO nanoparticles using Moringa Oleifera leaves

In this current assessment, BaO synthesized from Moringa Oleifera leaves were irradiated using 0-75 kGy gamma radiation and investigated its physical impacts. The x-ray diffraction (XRD) data demonstrated the synthesis of tetragonal BaO, and no phase deviation was observed after irradiation. As doses are increased, the overall crystallite size were decreased due to an increase in defects and disorders. The tetragonal BaO was evident in Fourier transform infrared (FTIR) spectra prior to and following irradiation, while peak intensities and wavenumbers varied considerably. The as-prepared BaO showed a spherical shape morphology, and Field emission scanning electron microscopy (FESEM) indicated no vital deviations in it after irradiation. As irradiation shifts from 0 to 75 kGy, optical bandgap was increased from 4.55 to 4.93 eV, evaluated using Kubelka-Munk (K-M) equation from UV-vis-NIR spectrophotometer. Opto-electronic and photonic devices have challenges in extreme radiation conditions, such as space and nuclear environments. So, these assessments suggested that BaO can withstand high levels of gamma photon and could be a good option for photonic and optoelectronic instruments in an extreme gamma-ray exposed conditions.

Perceptions of antibiotic stewardship programmes and determinants of antibiotic prescribing patterns among physicians in tertiary hospitals in Bangladesh: implications for future policy and practice

BACKGROUND

The concerning growth of antimicrobial resistance (AMR) renders common infections life-threatening due to irrational antibiotic use and a lack of effective antimicrobial stewardship programmes (ASPs).

AIM

To investigate the awareness, perceptions and practices of physicians regarding ASPs, AMR and antibiotic prescribing in tertiary care hospitals in Bangladesh.

METHODS

This hospital-based cross-sectional survey was conducted in 11 tertiary care hospitals across Bangladesh between September 2020 and January 2021. A semi-structured questionnaire was administered through face-to-face interviews for data collection. Descriptive and multi-variate analyses were performed using STATA Version 13.

RESULTS

In total, 559 physicians were enrolled in this survey. Overall, 40.6% [95% confidence interval (CI) 36.5-44.8] of physicians reported being aware of ASPs, and this figure was higher in public hospitals compared with private hospitals (43.8% vs 27.1%). None of the study hospitals had any ASP initiatives. More than half (55.1%) of the participants were willing to receive feedback from an ASP on their antibiotic selection. Only 30.9% of respondents stated that they wait for the findings of microbiological tests before prescribing antibiotics, although challenges included empiric use of broad-spectrum antibiotics, delayed laboratory results and the existence of drug-resistant patients. In contrast, physicians aware of ASPs were 33% (adjusted odds ratio 0.67, 95% CI 0.45-0.98; P=0.033) less likely to wait for laboratory results before prescribing antibiotics. However, 42.5% of physicians considered patient affordability of purchasing antibiotics when prescribing.

CONCLUSIONS

Physicians' fundamental knowledge of ASPs and rational antibiotic prescription were found to fall short of the standard. Context-specific and integrated ASP activities, availability and use of guidelines, and improved laboratory facilities are required to battle AMR in Bangladesh.

ψ(2S) Suppression in Pb-Pb Collisions at the LHC

The production of the ψ(2S) charmonium state was measured with ALICE in Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV, in the dimuon decay channel. A significant signal was observed for the first time at LHC energies down to zero transverse momentum, at forward rapidity (2.5 Collapse

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Substitution of lead with tin suppresses ionic transport in halide perovskite optoelectronics

Despite the rapid rise in the performance of a variety of perovskite optoelectronic devices with vertical charge transport, the effects of ion migration remain a common and longstanding Achilles' heel limiting the long-term operational stability of lead halide perovskite devices. However, there is still limited understanding of the impact of tin (Sn) substitution on the ion dynamics of lead (Pb) halide perovskites. Here, we employ scan-rate-dependent current-voltage measurements on Pb and mixed Pb-Sn perovskite solar cells to show that short circuit current losses at lower scan rates, which can be traced to the presence of mobile ions, are present in both kinds of perovskites. To understand the kinetics of ion migration, we carry out scan-rate-dependent hysteresis analyses and temperature-dependent impedance spectroscopy measurements, which demonstrate suppressed ion migration in Pb-Sn devices compared to their Pb-only analogues. By linking these experimental observations to first-principles calculations on mixed Pb-Sn perovskites, we reveal the key role played by Sn vacancies in increasing the iodide ion migration barrier due to local structural distortions. These results highlight the beneficial effect of Sn substitution in mitigating undesirable ion migration in halide perovskites, with potential implications for future device development.

Frequency of Post Endoscopic Retrograde Cholangiopancreatography Acute Pancreatitis in an Academic Hospital of Bangladesh

Post-ERCP acute pancreatitis (PEP) is a common and serious complication with high morbidity and mortality rates. There is a paucity of data on the frequency of PEP in a resource constraint setting like Bangladesh. Hence we have conducted a prospective study to determine the frequency of PEP and the factors associated with its occurrence. This prospective, observational study was carried out in Gastroenterology Department of Dhaka Medical College & Hospital, Dhaka, Bangladesh from April 2018 to December 2018 on the consecutive patients who underwent ERCP. PEP and its severity were diagnosed according to consensus definition. Serum lipase was done in all patients before procedure and 24 hours after procedure or if patient develops abdominal pain after the procedure which became earlier. Total 168 patients were included (mean age 46.97±14.35 years; male 72(43.0%). The most common indication of ERCP was choledocholithiasis 97(58.0%) followed by malignant biliary obstruction 45(27.0%), recurrent pyogenic cholangitis 8(5.0%), chronic pancreatitis 4(2.3%), biliary ascariasis 4(2.3%) and others 10(6.0%). Overall post ERCP complication rate was 46(27.3%) including cholangitis 29(17.3%), pancreatitis 16(9.5%), bleeding 12(7.1%), aspiration pneumonia 4(2.4%) and death 3(1.8%). Regarding the severity of PEP, 50.0%, 43.7% and 6.3% patients developed mild, moderate and severe pancreatitis respectively. Number of cannulation attempts >5 times [22(48%) vs. 17(14%); p=0.001], cannulation attempts duration more than 10 minutes [25(55%) vs. 27(22%); p=0.001], unintentional passage of guide wire into the pancreatic duct [8(17%) vs. 18(15%); p=0.001], pancreatic duct contrast injection [12(26%) vs. 2(1.6%); p=0.001] and pre-cut sphincterotomy [16(35%) vs. 6(4.9%); p=0.001] were significantly different between the patients who developed PEP compared to those who did not. In multiple logistic regressions analysis, pancreatic duct contrast injection was significantly associated with PEP [OR 25.523 with 95% CI (4.049- 100.0%)]. Around ten percent patients had developed PEP. Regarding the severity half of them were mild, 44.0% patients had moderate and 6.0% patient had severe type of pancreatitis. Difficult cannulation, unintentional passage of guide wire into the pancreas, pancreatic duct contrast injection and pre-cut sphincterotomy were associated with PEP. Among them pancreatic duct contrast injection had independent significance in the causation of PEP.

A Case Report on an Unusual Presentation of Pernicious Anemia

Pernicious anemia is an autoimmune disease leading to impaired absorption of dietary cobalamin. Patients with pernicious anemia can present with multiple hematological, neurological and gastrointestinal complaints. Herein, we have a case of pernicious anemia presenting with alternating bowel habit. This was challenging and unique as the patient didn't have any usual condition responsible for alternating bowel habit and it is not reported in cases of pernicious anemia either. The case is a 46-year-old male who was admitted with alternating bowel habit, paresthesia and fever for the last 6 months. Patient was found to be severely anemic. After full workup, he was diagnosed with pernicious anemia. The patient was treated with IM Injections of Vitamin B12. After 3 months of discharge, the patient was free of all the symptoms. This case emphasizes the importance of investigating anemic patients with alternating bowel habit for pernicious anemia and also the need to exclude other causes of this symptom before labeling it as pernicious anemia only.

The persistence of memory in ionic conduction probed by nonlinear optics

Predicting practical rates of transport in condensed phases enables the rational design of materials, devices and processes. This is especially critical to developing low-carbon energy technologies such as rechargeable batteries1-3. For ionic conduction, the collective mechanisms4,5, variation of conductivity with timescales6-8 and confinement9,10, and ambiguity in the phononic origin of translation11,12, call for a direct probe of the fundamental steps of ionic diffusion: ion hops. However, such hops are rare-event large-amplitude translations, and are challenging to excite and detect. Here we use single-cycle terahertz pumps to impulsively trigger ionic hopping in battery solid electrolytes. This is visualized by an induced transient birefringence, enabling direct probing of anisotropy in ionic hopping on the picosecond timescale. The relaxation of the transient signal measures the decay of orientational memory, and the production of entropy in diffusion. We extend experimental results using in silico transient birefringence to identify vibrational attempt frequencies for ion hopping. Using nonlinear optical methods, we probe ion transport at its fastest limit, distinguish correlated conduction mechanisms from a true random walk at the atomic scale, and demonstrate the connection between activated transport and the thermodynamics of information.

Measurements of Groomed-Jet Substructure of Charm Jets Tagged by D^{0} Mesons in Proton-Proton Collisions at sqrt[s]=13 TeV

Understanding the role of parton mass and Casimir color factors in the quantum chromodynamics parton shower represents an important step in characterizing the emission properties of heavy quarks. Recent experimental advances in jet substructure techniques have provided the opportunity to isolate and characterize gluon emissions from heavy quarks. In this Letter, the first direct experimental constraint on the charm-quark splitting function is presented, obtained via the measurement of the groomed shared momentum fraction of the first splitting in charm jets, tagged by a reconstructed D^{0} meson. The measurement is made in proton-proton collisions at sqrt[s]=13  TeV, in the low jet transverse-momentum interval of 15≤p_{T}^{jet ch}<30  GeV/c where the emission properties are sensitive to parton mass effects. In addition, the opening angle of the first perturbative emission of the charm quark, as well as the number of perturbative emissions it undergoes, is reported. Comparisons to measurements of an inclusive-jet sample show a steeper splitting function for charm quarks compared with gluons and light quarks. Charm quarks also undergo fewer perturbative emissions in the parton shower, with a reduced probability of large-angle emissions.

Measurement of the Lifetime and Λ Separation Energy of _{Λ}^{3}H

The most precise measurements to date of the _{Λ}^{3}H lifetime τ and Λ separation energy B_{Λ} are obtained using the data sample of Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV collected by ALICE at the LHC. The _{Λ}^{3}H is reconstructed via its charged two-body mesonic decay channel (_{Λ}^{3}H→^{3}He+π^{-} and the charge-conjugate process). The measured values τ=[253±11(stat)±6(syst)]  ps and B_{Λ}=[102±63(stat)±67(syst)]  keV are compatible with predictions from effective field theories and confirm that the _{Λ}^{3}H structure is consistent with a weakly bound system.

Hand hygiene compliance and associated factors among healthcare workers in selected tertiary-care hospitals in Bangladesh

BACKGROUND

Hand hygiene (HH) is a fundamental element of patient safety. Adherence to HH among healthcare workers (HCWs) varies greatly depending on a range of factors, including risk perceptions, institutional culture, auditing mechanisms, and availability of HH supplies.

AIMS

This study aimed to evaluate HH compliance and associated factors among HCWs in selected tertiary-care hospitals in Bangladesh.

METHODS

During September 2020 to May 2021, we conducted non-participatory observations at 10 tertiary-care hospitals using the WHO's '5-moments for hand hygiene tool' to record HH compliance among physicians, nurses and cleaning staff. We also performed semi-structured interviews to determine the key barriers to complying with HH.

RESULTS

We observed 14,668 hand hygiene opportunities. The overall HH compliance was 25.3%, the highest among nurses (28.5%), and the lowest among cleaning staff (9.9%). HCWs in public hospitals had significantly higher odds of complying with HH practices than those in private hospitals (adjusted odds ratio: 1.73, 95% CI: 1.55-1.93). The odds of performing HH after touching a patient were 3.36 times higher compared with before touching a patient (95% CI: 2.90-3.90). The reported key barriers to performing HH were insufficient supplies (57.9%), skin reactions (26.3%), workload (26.3%) and lack of facilities (22.7%). Overall, observed HH supplies were available in 81.7% of wards for physicians and 95.1% of wards for nurses, however, no designated HH facilities were found for the cleaning staff.

CONCLUSIONS

HH compliance among HCWs fell significantly short of the standard for safe patient care. Inadequate HH supplies demonstrate a lack of prioritizing, promoting and investing in infection prevention and control.

Seasonal variation, contamination and ecological risk assessment of heavy metals in sediments of coastal wetlands along the Bay of Bengal

Functioning of coastal wetland habitats is essential for the ecosystem integrity and sustainability of coastal development that enables human progress along transitional waterways. However, these habitats are continuously being affected by a variety of pollutants including metallic elements. In this study, seasonal variation, pollution status and ecological risks of heavy metals (Cr, Mn, Co, Ni, As, Cu, Zn and Pb) in surface sediment of the several types of coastal wetlands (estuaries, mudflats, sandy beaches, mangroves, and saltmarshes) were detected by using X-ray fluorescence (EDXRF) spectrometry. The results showed that the mean concentration level of metals in the surficial sediment samples followed the order of Cu (84.06 ± 8.60 μg/g) > Zn (51.00 ± 8.97 μg/g) > Mn (38.25 ± 11.34 μg/g) > Cr (3.52 ± 0.91 μg/g) > Pb (0.27 ± 0.13 μg/g) > Co (0.24 ± 0.13 μg/g) > As (0.21 ± 0.12 μg/g) > Ni (0.16 ± 0.08 μg/g). In comparison to the pre-monsoon period, the post-monsoon season had higher concentrations of heavy metals while the overall accumulation level of metals in the wetlands exhibited a pattern of estuarine wetland (28.47 ± 31.35 μg/g) > mangrove (22.23 ± 30.79 μg/g) > mudflat (21.79 ± 29.71 μg/g) > sandy beach (21.47 ± 28.15 μg/g) > saltmarsh (21.28 ± 30.02 μg/g). Although, the pollution assessment indices e.g., contamination factor (CF), degree of contamination (CD), geoaccumulation index (Igeo) and pollution load index (PLI) showed minimal levels of contamination in the studied sites, enrichment factor (EF) suggested greater enrichment of the metals in the pre-monsoon season but with the lowest ecological risk (RI < 40) in both seasons. Cluster analysis, principal component analysis (PCA), and Pearson's correlation were performed to determine the sources of heavy metals in collected samples which specified that Pb, As, Co and Ni predominantly came from natural sources whereas Cu, Mn, Zn and Cr emerged from anthropogenic sources such as industrial effluents, domestic wastewater, fertilizer or pesticide consumption on farmland along the riverbank, vessel emissions, and the confluence of tributary rivers.

3D Lumerical simulation of silicon photodiodes with microholes for high-speed short-reach intra-datacenter interconnects

3D simulations are conducted using Lumerical software to study the performance of surface illuminated silicon positive-intrinsic-negative photodiodes with microholes. Drift-diffusion equations are solved including the effects of carrier lifetime due to Shockley-Read-Hall and Auger recombination mechanisms, as well as high field mobility. Lumerical's FDTD tool is used to determine the light absorption in the device. The generation profile is imported to Lumerical's CHARGE tool to determine the transient-limited impulse response. An equivalent circuit of the photodiode with microholes is developed for the simulation of an end-to-end high-speed system. Simulation results show an open eye diagram at 50 Gbps for 20µm×20µm devices.

Measurement of the J/ψ Polarization with Respect to the Event Plane in Pb-Pb Collisions at the LHC

We study the polarization of inclusive J/ψ produced in Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV at the LHC in the dimuon channel, via the measurement of the angular distribution of its decay products. We perform the study in the rapidity region 2.5 Collapse

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First Measurement of Antideuteron Number Fluctuations at Energies Available at the Large Hadron Collider

The first measurement of event-by-event antideuteron number fluctuations in high energy heavy-ion collisions is presented. The measurements are carried out at midrapidity (|η|<0.8) as a function of collision centrality in Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV using the ALICE detector. A significant negative correlation between the produced antiprotons and antideuterons is observed in all collision centralities. The results are compared with a state-of-the-art coalescence calculation. While it describes the ratio of higher order cumulants of the antideuteron multiplicity distribution, it fails to describe quantitatively the magnitude of the correlation between antiproton and antideuteron production. On the other hand, thermal-statistical model calculations describe all the measured observables within uncertainties only for correlation volumes that are different with respect to those describing proton yields and a similar measurement of net-proton number fluctuations.

Enhanced Deuteron Coalescence Probability in Jets

The transverse-momentum (p_{T}) spectra and coalescence parameters B_{2} of (anti)deuterons are measured in p-p collisions at sqrt[s]=13  TeV for the first time in and out of jets. In this measurement, the direction of the leading particle with the highest p_{T} in the event (p_{T}^{lead}>5  GeV/c) is used as an approximation for the jet axis. The event is consequently divided into three azimuthal regions, and the jet signal is obtained as the difference between the toward region, that contains jet fragmentation products in addition to the underlying event (UE), and the transverse region, which is dominated by the UE. The coalescence parameter in the jet is found to be approximately a factor of 10 larger than that in the underlying event. This experimental observation is consistent with the coalescence picture and can be attributed to the smaller average phase-space distance between nucleons in the jet cone as compared with the underlying event. The results presented in this Letter are compared to predictions from a simple nucleon coalescence model, where the phase-space distributions of nucleons are generated using pythia8 with the Monash 2013 tuning, and to predictions from a deuteron production model based on ordinary nuclear reactions with parametrized energy-dependent cross sections tuned on data. The latter model is implemented in pythia8.3. Both models reproduce the observed large difference between in-jet and out-of-jet coalescence parameters, although the almost flat trend of the B_{2}^{Jet} is not reproduced by the models, which instead give a decreasing trend.

Correlation between Depth of Medial and Lateral Curvatures of Clavicle

Having the first bone to ossify clavicle is a bone of pectoral girdle. It is the only bony attachment between the trunk and upper limb. To obtain the precise data that is required to investigate the range in size and morphological features of the human clavicle, a study was undertaken on dry human clavicles which had been sourced from the Department of Anatomy. The purpose for undertaking this study was to obtain baseline data on the clavicular bow in the transverse plane. This cross-sectional descriptive study having some analytical components was done among 150 (65 right and 85 left) fully ossified dry clavicles in Mymensingh Medical College, Bangladesh from January 2020 to December 2020. Sample which met the inclusion criteria was collected through non random sampling technique, from Anatomy department of Mymensingh Medical College and Community Based Medical College Bangladesh. The parameters (the depth of medial and lateral curvatures) were measured with the help of rigid osteometry board and were expressed in millimeter. In the current study, the mean±SD depth of medial curvature of 65 clavicles of right side was 15.54±3.54mm and 15.45±3.24mm of 85 left clavicles. The mean±SD depth of lateral curvature of right side was 11.71±2.54mm and of left side was 9.21±2.31mm. Correlation was done in between depth of medial and lateral curvatures on both sides and the regression line showed positive correlation but these differences were statistically non-significant on both sides.

The Impact of Hypertension, Coronary Heart Diseases and Diabetes on COVID-19 Illness

This study tried to understand the impact that hypertension, coronary heart diseases and diabetes can have on the intensity of coronavirus within the human body. This study was conducted using a systematic review process where secondary data have been collected from 10 previously published research papers. Most of the individuals contracting COVID-19 are also suffering from diabetes, cardiovascular diseases and hypertension. The studies used to carry out this systematic review have exhibited a pattern that indicates a strong correlation. That being said, because of the possibility of extraneous variables, most of the studies at this point have significant drawbacks. Many of such variables for example, smoking behavior or level of fitness have not been considered while selecting sample for most of the studies. Therefore, more highly targeted studies need to be carried out for understanding this disease and the long- and short-term impact it can have.

Phlebectomy versus Sclerotherapy in Varicose Vein Patients: A Comparative Study

Varicose veins are part of the spectrum of chronic venous disease and include spider telangiectasias, reticular veins, and true varicosities. It may present without advanced signs of chronic venous insufficiency. Sclerotherapy is a treatment choice for patients with varicose veins of lower extremity; it uses the intravenous injection of chemical drugs to achieve the goal of inflammatory occlusion. Phlebectomy, a minimally invasive procedure usually used for higher diameter of varicose veins at the surface of the skin. Objective of the study was to compare the outcome of Phlebectomy and Sclerotherapy in varicose vein patients. It was a quasi experimental study was conducted in the Department of Vascular Surgery in Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka during the period of June 2019 to May 2020. Patients admitted with varicose vein and varicosity of the lower limbs with valves and perforator incompetence in the Department of Vascular Surgery, BSMMU, Dhaka, Bangladesh. During this period 60 patients were selected purposive randomly. Patients were divided to 30 patients were treated with Phlebectomy (Group I) 30 patients were treated with Sclerotherapy (Group II). Data were collected according to the pre-designed semi-structured data collection sheet. After editing data analysis were carried out by using the Statistical Package for Social Science (SPSS) version 22.0 Windows software. This study shows average age 40.73±15.50 years in Phlebectomy (Group I) and 38.43±11.08 years in Sclerotherapy (Group II). Males are more commonly involved than females between two groups which was 76.7% in Phlebectomy (Group I) and 70.0% in Sclerotherapy (Group II). The change CEAP improved to 93.3% in patients who underwent phlebectomy when compared to 83.3% in patients who underwent sclerotherapy. During the follow-up with duplex at treated veins showed 93.3% complete occlusion of treated veins in the phlebectomy group, while only 70.0% of the patients in the sclerotherapy group showed evidence of complete occlusion. In phlebectomy group recurrence of leg varicosities were found 6.7% of the patients, while 26.7% of the patients in the sclerotherapy group. The difference was statistically significant between two groups (p=0.038). This study shows phlebectomy to be much better option than sclerotherapy for the treatment of varicose veins and hence can be used routinely. Both phlebectomy and sclerotherapy not only revealed minimal time taken for return to normal activity but also proved to be safer with regard to complications.

Role of White Blood Cell Count, Immature to Total Ratio and C-Reactive Protein in Early Detection of Clinically Suspected Neonatal Sepsis

Despite recent advances in neonatal care, early detection of neonatal sepsis still remains challenging. Positive blood culture is the gold standard for definitive diagnosis of neonatal sepsis but is time consuming and demands a well equipped laboratory setting. Therefore, it becomes imperative to evaluate usefulness of white blood cell count, Immature to total (IT) ratio and C-reactive protein as potential markers in the early diagnosis of neonatal sepsis. The objective of the study was to evaluate role of white blood cell count, IT ratio and C-reactive protein in early detection of clinically suspected neonatal sepsis. This cross-sectional descriptive study was conducted from January 2017 to December 2018 at Special Care Newborn Unit (SCANU) of Rangpur Medical College Hospital, Rangpur, Bangladesh. After parental permission and ethical clearance, a total of 70 eligible neonates were included into the study. Estimation of total white blood cell count, IT ratio and C-reactive protein as well as blood culture were done for each case. Significance for Chi-Square test and Pearson's correlation coefficient test was predetermined as p<0.05. Of the total 70 neonates studied, 19(27.14%) were blood culture positive and most common organism was Escherichia coli (7/14, 37.0%). Among individual and combination tests, CRP was highly sensitive (100%) followed by WBC count (74.94%). Highly specific tests in diagnosing sepsis were combination test of IT ratio and CRP (88.23%) followed by combination test of WBC count and CRP (82.35%). Positive predictive value (PPV) was high for combination test of WBC count and CRP (90.90%) followed by combination test of IT ratio and CRP (90.47%). Negative predictive value (NPV) was high in CRP (100.0%) followed by WBC count (89.19%). IT ratio positively correlated with CRP (p=0.002) and there was significant association between raised CRP and WBC count (p=0.005) in neonatal sepsis. Diagnostic role of both individual and combination tests were significant in early detection of clinically suspected neonatal sepsis while awaiting results of blood culture. However, none of the combination tests were able to achieve 100.0% sensitivity.

Outcomes of Varus Derotation Femoral Osteotomy By Angle Blade Plate in Legg-Calve-Perthes Disease for Patient Above Eight Years of Age in The Lateral Pillar B or B/C Group

Legg-Calve-Perthes disease (LCPD) that starts after 8 years (late onset) usually follow more aggressive course and the long-term outcome is also poor. Treatment method of LCPD that will produce best results is controversial particularly if the patients are with late-onset presentation. This prospective study was conducted from January 2015 to January 2019 at Dhaka Medical College Hospital and Health N Hope Hospital, Dhaka, Bangladesh. We evaluated the radiographic outcomes for patients who had varus derotation femoral osteotomy (VDRO). We followed up 16 patients who had femoral varus osteotomy. All patients were above 8 years of age at clinical onset. The involvement of femoral epiphysis was in either in B or B/C in lateral pillar classification. All patients had MRI done to confirm radiological diagnosis and classification. The mean age was 9.5 years (range, 8 to 12 years). Final outcome was evaluated by using the Stulberg classification which was radiological. Important exclusion criteria were patient with bilateral involvement and requirement of femoral varus >30 degree. We had 81.25% of our patient with satisfactory outcomes. Among them there were Stulberg grade I, 0 cases; Stulberg grade II, 13 cases (81.25%); Stulberg III, 3 cases (18.75%), Stulberg IV and V both 0 case each. The surgical outcomes for varus derotation femoral osteotomy in late onset LCPD patients over 8 years old were showing the good results than other modalities of non surgical and surgical methods.

Draft Genome Sequence of the Multidrug-Resistant Citrobacter freundii 132-2 Strain Isolated from a Domestic Duck in Bangladesh

We sequenced a multidrug-resistant strain of Citrobacter freundii, 132-2, isolated from a cloacal swab sample of a domestic duck. The whole genome of the C. freundii 132-2 strain had a length of 5,097,592 bp, 62 contigs, two plasmids, and an average G+C content of 51.85%, with a 105.0× genome coverage.

Anion-polarisation-directed short-range-order in antiperovskite Li2FeSO

Short-range ordering in cation-disordered cathodes can have a significant effect on their electrochemical properties. Here, we characterise the cation short-range order in the antiperovskite cathode material Li₂FeSO, using density functional theory, Monte Carlo simulations, and synchrotron X-ray pair-distribution-function data. We predict partial short-range cation-ordering, characterised by favourable OLi₄Fe₂ oxygen coordination with a preference for polar cis-OLi₄Fe₂ over non-polar trans-OLi₄Fe₂ configurations. This preference for polar cation configurations produces long-range disorder, in agreement with experimental data. The predicted short-range-order preference contrasts with that for a simple point-charge model, which instead predicts preferential trans-OLi₄Fe₂ oxygen coordination and corresponding long-range crystallographic order. The absence of long-range order in Li₂FeSO can therefore be attributed to the relative stability of cis-OLi₄Fe₂ and other non-OLi₄Fe₂ oxygen-coordination motifs. We show that this effect is associated with the polarisation of oxide and sulfide anions in polar coordination environments, which stabilises these polar short-range cation orderings. We propose that similar anion-polarisation-directed short-range-ordering may be present in other heterocationic materials that contain cations with different formal charges. Our analysis illustrates the limitations of using simple point-charge models to predict the structure of cation-disordered materials, where other factors, such as anion polarisation, may play a critical role in directing both short- and long-range structural correlations.

Food safety policy enforcement and associated actions reduce turmeric lead chromate adulteration across Bangladesh

Turmeric adulterated with lead chromate pigment has been previously identified as a primary source of lead exposure in Bangladesh. This study assesses the impact of a multi-faceted intervention between 2017 and 2021 to reduce lead-tainted turmeric in Bangladesh. The intervention involved: i) disseminating findings from scientific studies via news media that identified turmeric as a source of lead poisoning, ii) educating consumers and businesspeople about the risks of lead chromate in turmeric via public notices and face-to-face meetings, and iii) collaborating with the Bangladesh Food Safety Authority to utilize a rapid lead detection technology to enforce policy disallowing turmeric adulteration. Before and after the intervention, evidence of lead chromate turmeric adulteration was assessed at the nation's largest turmeric wholesale market and at turmeric polishing mills across the country. Blood lead levels of workers at two mills were also assessed. Forty-seven interviews were conducted with consumers, businesspeople, and government officials to assess changes in supply, demand, and regulatory capacity. The proportion of market turmeric samples containing detectable lead decreased from 47% pre-intervention in 2019 to 0% in 2021 (n = 631, p < 0.0001). The proportion of mills with direct evidence of lead chromate adulteration (pigment on-site) decreased from 30% pre-intervention in 2017 to 0% in 2021 (n = 33, p < 0.0001). Blood lead levels dropped a median of 30% (IQR: 21-43%), while the 90th percentile dropped 49% from 18.2 μg/dL to 9.2 μg/dL 16 months after the intervention (n = 15, p = 0.033). Media attention, credible information, rapid lead detection tools and swift government action to enforce penalties all contributed to the intervention's success. Subsequent efforts should evaluate if this is an example of an effective intervention that can be replicated to reduce lead chromate adulteration of spices globally.

A computational study of the thortveitite structure of zinc pyrovanadate, Zn2V2O7, under pressure

We performed a pressure-driven study of zinc pyrovanadate, Zn₂V₂O₇, using the first-principles approach under the framework of density functional theory (DFT). Zn₂V₂O₇ crystalizes in a monoclinic (α-phase) structure with the space group C2/c at ambient pressure. In comparison with the ambient phase, there are four different high-pressure phases, namely β, γ, κ and δ, found at 0.7, 3.8, 4.8 and 5.3 GPa, respectively. The detailed crystallographic analysis as well as their structures is consistent with the theory and experiment reported in the literature. All phases including the ambient phase are mechanically stable, elastically anisotropic and malleable. The compressibility of the studied pyrovanadate is higher than that of the other meta- and pyrovanadates. The energy dispersion of these studied phases reveals that they are indirect band gap semiconductors with wide band gap energies. The band gap energies follow a reduced trend with pressure except the κ-phase. The effective masses for all of these studied phases were computed from their corresponding band structures. The values of energy gaps obtained from the band structures are almost similar to the optical band gap obtained from the optical absorption spectra, as estimated by the Wood-Tauc theory.

Outcomes of WHO-conforming, longer, all-oral multidrug-resistant TB regimens and analysis implications

BACKGROUND: Evidence of the effectiveness of the WHO-recommended design of longer individualized regimens for multidrug- or rifampicin-resistant TB (MDR/RR-TB) is limited.OBJECTIVES: To report end-of-treatment outcomes for MDR/RR-TB patients from a 2015-2018 multi-country cohort that received a regimen consistent with current 2022 WHO updated recommendations and describe the complexities of comparing regimens.METHODS: We analyzed a subset of participants from the endTB Observational Study who initiated a longer MDR/RR-TB regimen that was consistent with subsequent 2022 WHO guidance on regimen design for longer treatments. We excluded individuals who received an injectable agent or who received fewer than four likely effective drugs.RESULTS: Of the 759 participants analyzed, 607 (80.0%, 95% CI 77.0-82.7) experienced successful end-of-treatment outcomes. The frequency of success was high across groups, whether stratified on number of Group A drugs or fluoroquinolone resistance, and ranged from 72.1% to 90.0%. Regimens were highly variable regarding composition and the duration of individual drugs.CONCLUSIONS: Longer, all-oral, individualized regimens that were consistent with 2022 WHO guidance on regimen design had high frequencies of treatment success. Heterogeneous regimen compositions and drug durations precluded meaningful comparisons. Future research should examine which combinations of drugs maximize safety/tolerability and effectiveness.

Rare Presentation of Giant Cell Tumors of the Tendon Sheath: Bilateral Involvement of Tendoachilles

Giant cell tumor of tendon sheath arises from the synovium of tendon sheaths, joints, or bursa, mostly affects adults between 30 and 50 years of age, and is slightly more common in females. It corresponds to a localized form of pigmented villonodular synovitis (PVNS). Typically occur in the hand where they represent the second most common type of soft tissue tumors after synovial ganglions. Bilateral giant cell tumor of tendon sheath of tendoachilles is a rare presentation. We report the case of a 22-years-old female presenting with pain in both ankles without any history of trauma. On clinical examination, tenderness on both tendoachilles and local indurations were observed. Ultrasonography showed focal thickening of Achilles tendon bilaterally, and Doppler demonstrated increased flow in peritendinous area. MRI findings showed that most of the tumor had intermediate signal intensity and portions of the tumor had low signal intensity. Fine needle aspiration cytology confirmed the diagnosis of giant cell tumor of tendon sheath. Excision biopsy was done with no recurrence on subsequent follow-up.

A Case of Bilateral Middle Cerebral Artery Stenosis with Unilateral M1 Stenting

Stroke is not only the third leading cause of death in Bangladesh but it also causes a high number of disability adjusted life years loss (485 per 10,000 people). Appropriate treatment of recurrent stroke has to be established. Here we present A 60 year's old male patient with history of recurrent stroke who came in our out patient department. He had progressing bilateral middle cerebral artery atherosclerotic stenosis (100.0% on right side and 52.0% on left side) which was less severs but symptomatic at dominant hemisphere (left). Percutaneous transluminal angioplasty with stenting was done to prevent further ischemia and to increase the blood supply of remaining brain parenchyma. On post stenting follow-up patient did not suffered from any new event of stroke for about 22 months. Percutaneous transluminal angioplasty with stenting is an effective procedure to prevent recurrent stroke for intracranial atherosclerotic disease.

Correlation between Antero-posterior Diameter and Vertical Diameter of Both Ends of Fully Ossified Dry Human Clavicle

Clavicle is an upper limb locomotory bone which helps in formation of pectoral girdle and connected the upper limb with axial skeleton. There is no baseline data of clavicle in contrast to demographic variation in our country, so the study was designed to obtain baseline data on clavicle for anthropological, forensic and clinical use. This descriptive cross-sectional study was done among 150 (65 right and 85 left) fully ossified dry human clavicle in Mymensingh Medical College, Mymensingh, Bangladesh from January 2020 to December 2020. Sample was collected by the help of nonrandom purposive sampling technique from Department of Anatomy of Mymensingh Medical College and Community Based Medical College, Bangladesh, Mymensingh. The parameters were the antero-posterior diameter and vertical diameter of sternal and acromial ends of clavicle, measured with the help of digital vernier slide caliper and expressed in millimeter. In the current study the mean±SD antero-posterior diameter of sternal end of 65 clavicles of right side was 21.97±2.889mm and 85 clavicles of left side were 20.30±3.459mm. The mean±SD antero-posterior diameter of acromial end of 65 right sided clavicles was 21.96±5.161mm and 85 clavicles of left side were 21.00±4.002mm. Correlation was done in between antero-posterior diameter and vertical diameter of sternal end of clavicle and the differences were highly significant on both sides. Similarly, when correlation was done for the acromial end of clavicle the difference was found non-significant on right side and highly significant on left side.

Modified Snodgrass Urethroplasty for Distal Penile Hypospadias: Our Experience at BSMMU Hospital

Hypospadias is a developmental defect of male urethra characterized by absence of meatal opening at the tip of glans but is present at the ventral surface of penis anywhere along the shaft, even in the perineum. Usually this defect is associated with ventrally curved penis. Surgery is the single option to correct this birth defect. More than 300 techniques have been developed but none is universally acceptable as because, surgery is usually associated with fistula. Rate of fistula formation varies from technique to technique. Now a day, Snodgrass technique is widely practiced because of its low rate of fistula formation. Many factors are responsible for this post-operative complication. Most important one is developmentally defective ventral penile skin where some local factors like vascular and collagen tissues are insufficient. This observational study was performed to evaluate the role of dorsal vascular flap over the neourethra following urethroplasty by Snodgrass technique in terms of post-operative fistula formation in the Department of Paediatric Surgery, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh from March 2018 to March 2020. A total of 39 patients with distal penile hypospadias were included in this study. All underwent Snodgrass urethroplasty with additional dorsal vascular flap over the neourethra to support this ventrally deficient local factor. The outcome in terms of post operative urethrocutaneous fistula was evaluated. Only two patients (5.15%) developed urethrocutaneous fistula. In conclusion, addition of dorsal vascular flap over the neourethra by Snodgrass technique reduces the rate of the fistula formation.

Defect-driven anomalous transport in fast-ion conducting solid electrolytes

Solid-state ionic conduction is a key enabler of electrochemical energy storage and conversion. The mechanistic connections between material processing, defect chemistry, transport dynamics and practical performance are of considerable importance but remain incomplete. Here, inspired by studies of fluids and biophysical systems, we re-examine anomalous diffusion in the iconic two-dimensional fast-ion conductors, the β- and β″-aluminas. Using large-scale simulations, we reproduce the frequency dependence of alternating-current ionic conductivity data. We show how the distribution of charge-compensating defects, modulated by processing, drives static and dynamic disorder and leads to persistent subdiffusive ion transport at macroscopic timescales. We deconvolute the effects of repulsions between mobile ions, the attraction between the mobile ions and charge-compensating defects, and geometric crowding on ionic conductivity. Finally, our characterization of memory effects in transport connects atomistic defect chemistry to macroscopic performance with minimal assumptions and enables mechanism-driven 'atoms-to-device' optimization of fast-ion conductors.

Examining the discourse regarding the delivery of occupational infection prevention and control training to healthcare workers: a scoping review of pandemic plans of 23 countries

BACKGROUND

Over the years, countries reformed their pandemic plans but still healthcare systems were unprepared to handle the COVID-19 pandemic. Throughout the COVID-19 pandemic, healthcare workers (HCWs) raised issues around shortage of personal protective equipment (PPE), inadequate occupational infection prevention and control (IPC) training, lack of guidance regarding reuse/extended use of PPE and absence of HCWs.

OBJECTIVE

The objective of this scoping review was to compare national and transnational pandemic plans and COVID-19 guidelines for the inclusion of recommendations regarding pandemic-specific occupational IPC training for HCWs, as well as strategies for managing the surge in PPE needs and staffing.

INCLUSION CRITERIA

From each of the six WHO defined world regions, four countries with the highest burden of COVID-19 cases (as of mid-2020) were selected and attempted to locate the relevant pandemic plans and COVID-19 guidelines.

METHODS

Searches were undertaken of 1: National Guidelines Clearinghouse, 2: websites of international public healthcare agencies such as WHO, the European Centre for Disease Prevention and Control (ECDC) and, 3: in-country health departments/Ministry of Health/Department of Public Health, between June 2020 and July 2021. The data were summarised under six themes drawn from publicly available pandemic plans and COVID-19 (IPC) guidelines of WHO, ECDC and 23 countries.

RESULTS

The WHO, ECDC and 14 countries reported pandemic-specific IPC training; however, only four discussed training HCWs on correct PPE use; six countries listed strategies to manage the surge in demand of HCWs, while only five discussed managing the shortage of PPE. None of the COVID-19 guidelines recommended training HCWs for correct reuse or extended use of PPE and only one country's guideline outlined mandatory HCWs attendance and delivery of training in a regional language.

CONCLUSION

Pandemic plans should be revised to include guiding principles regarding the delivery of pandemic specific IPC training. There is also a need to provide guidance on when countries should consider reuse and extended use of PPE. This discourse should also be reflected in disease-specific pandemic guidelines, like COVID-19 (IPC) guidelines. The aim of this review is to assist international health agencies in generating evidence-based guideline updates.

What does family involvement in care provision look like across hospital settings in Bangladesh, Indonesia, and South Korea?

BACKGROUND

Family members provide care whilst staying in the patient's room across a range of cultural settings, irrespective of resource availability in many Asian countries. This has been reported as a contributing factor to the spread of several outbreaks, including COVID-19. Despite these reports, very little is known about the risk of healthcare-associated infection (HAI) transmission related to the involvement of family and private carers in the clinical setting. As a starting point to understanding this issue, this study aimed to provide insights regarding the patient care activities undertaken by family and private carers and the guidance provided to these carers around infection control measures in hospitals located in Bangladesh, Indonesia, and South Korea.

METHOD

A qualitative study involving 57 semi-structured interviews was undertaken in five tertiary level hospitals across the selected countries. Two groups of individuals were interviewed: (1) patients and their family carers and private carers; and (2) healthcare workers, including doctors, nurses, hospital managers and staff members. Drawing upon the principles of grounded theory, an inductive approach to data analysis using thematic analysis was adopted.

RESULTS

Five main themes were generated from the analysis of the data: (1) expectation of family carers staying with a patient; (2) residing in the patient's environment: (3) caring activities undertaken by family carers; (4) supporting and educating family carers and (5) communication around healthcare-associated infection and infection prevention and control.

CONCLUSION

Based on the types of activities being undertaken, coupled with the length of time family and private carers are residing within the clinical setting, coupled with an apparent lack of guidance being given around IPC, more needs to be done to ensure that these carers are not being inadvertently exposed to HAI's or other occupational risks.

Management of Neglected Rupture of Tendoachilles with Long Gap by Flexor Hallucis Longus Tendon Transfer

The tendo achilles is one of most important tendon in human body which often injured through direct trauma or indirect stress on a weakened tendon. Longer the duration after injury the injured parts likely to move apart, fibrosis and degeneration leading to difficulty in repair or reconstruction. Usually a phase of 4 weeks or more without specific treatment is regarded as chronic or neglected rupture. Different authors described many management protocols about the tendo achilles rupture but there is no procedure of choice for neglected rupture with long gap. Prospective case series of 21 patients of neglected tendo achilles rupture with long gap treated with flexor hallucis longus tendon (FHLT) transfer was taken for study from January 2019 to December 2020 in Mymensingh Medical College Hospital, Bangladesh. Average age of patients was 39.47 years with range 22-65 years. Fifteen (15) cases of traumatic rupture in this study with average age 32.66 years and pathologic 6 cases with average age 56.5 years were recorded. We grafted FHLT from channel by incising Henry's knot. Krackow et al.'s technique was followed for tendon mobilization and bone fixation. We made procedure simpler and cheaper; instead of using interference screw the sutured tendon pulled through the heel and anchored over rubber tube or button by Cole method. Post-operative complications were less with one patient with superficial infection which eventually recovered 3 cases of mild pain and 2 cases of numbness. Questionnaire for surgical outcome measure are satisfactory in 19 patients (90.47%). Final follow up AOFAS score at 6 month (91.61±5.41) was highly significant (p<0.001) in comparison to preoperative score (38.71±9.78). These are comparable to other study. Above mentioned scores indicate the reliability of the surgical system. But our study is a prospective case series with minimum cases. To establish the best procedure for neglected tendo achilles rupture with long gap we recommend further study with larger group and Randomized Controlled Trial (RCT) study among different procedure.

Pattern of Initial Clinical Presentation of Systemic Lupus Erythematosus: A Hospital-Based Cross-Sectional Study from Bangladesh

Systemic lupus erythematosus (SLE) is an autoimmune disorder involving multiple systems and often presents with diverse clinical manifestations. The objective of the present study was to investigate the initial clinical presentations of SLE patients attending a tertiary care hospital in Bangladesh. This cross-sectional study was conducted among 85 SLE patients diagnosed according to the 1997 ACR Revised Criteria for Classification of SLE attending the Lupus Clinic of Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh from January 2012 to June 2013. Sociodemographic and clinical data were collected from patient interviews, physical examinations and medical records. Almost 75.0% of the patients aged below 30 years had a female predominance (male-female ratio 1:5.6). Fever (71.0%), joint pain (60.0%) and alopecia (28.0%) were the most common initial presentations among the patients. Constitutional symptoms such as fatigue, malaise and weakness (23.5%), malar rash (21.0%), oral ulcer (20.0%), photosensitivity (15.0%) and Raynaud's phenomenon (13.0%) were also present in variable proportions. The musculoskeletal and mucocutaneous systems were most commonly affected (85.0% and 75.0% respectively), followed by lupus nephritis (40.0%), hematological symptoms (22.0%) and vasculitis (17.6%). Out of 85 patients, 78 (92.0%) tested positive for anti-nuclear antibodies. SLE patients commonly present with musculoskeletal and nonspecific symptoms at the initial phase. Hence, physicians should consider this clinical and immunological evidence along with conventional symptoms included in the ACR criteria.

Echocardiographic Evaluation of Cardiac Changes in Patients with Hypothyroidism and the Response to Treatment

Thyroid hormone acts on heart and peripheral vascular system in multiple ways. Most of the cardiac manifestations are reversible with adequate and timely thyroid therapy. Echocardiographic changes are present in patients with untreated hypothyroidism and the changes are reversible with treatment. Aim of the study was to evaluate the structural and functional changes of the heart in hypothyroid patients and its response to treatment. This prospective observational study was performed in the Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh from November 2012 to April 2013. The study included 35 cases and 35 control based on their thyroid hormonal status. The cases were previously untreated for hypothyroidism. By 2D and M-mode echocardiography LV septal wall and posterior wall thickness, LVIDD, LVIDS, LA and Aortic diameter and ejection fraction were measured. Mitral inflow pattern was observed through pulse wave Doppler and peak E velocity, a velocity and E/A ratio were noted. All the observations were noted both in cases and controls and in cases after normalization of hypothyroid status. Echocardiographic variables showed that septal wall and posterior wall thickness, LVIDD and LVIDS were higher in the cases than those in the control group. Left ventricular ejection fraction was lower in case group compared to control group. Of the mitral inflow parameters, a velocity was higher and E/A ratio lower in cases than those in control group. Following treatment of >3 months the septal wall and posterior wall thicknesses were reduced significantly (p<0.001 and p<0.001 respectively) and Left ventricular ejection fraction was also improved significantly (p<0.001) from its baseline status. Of the mitral inflow parameters, E-velocity was significantly increased, A-velocity significantly decreased and E/A ratio significantly increased from their baseline figures (p=0.016, p=0.032 and p<0.001 respectively). Cardiovascular complications of hypothyroidism increase the morbidity of the patients. Results of our study showed importance of early diagnosis and prompt treatment reversed the condition and that will diminish the extent of cardiac complications.

Safety and Feasibility of Trans Radial Percutaneous Coronary Intervention Approach in Elderly Patients with Acute Coronary Syndrome

Coronary catheterization is usually performed using the transfemoral approach but trans-radial has been increasingly used as an alternative to transfemoral approach due to less vascular complications, earlier ambulation time and improved patient comfort. The aim of the study was to compare the safety and feasibility of trans-radial and transfemoral PCI in the elderly ACS patients. This prospective observational study was conducted in the NICVD, Dhaka from October 2017 to September 2018. Total 80 patients were categorized into two groups according to the approach of PCI. Group I consists 40 patients who underwent trans-radial PCI and Group II consists 40 patients who underwent transfemoral PCI. Patients with abnormal Allen's test, history of CABG, CKD were excluded. Patient's demographics were same in both groups. The mean procedural time in min (37.44±5.13 vs. 34.42±4.42, p=0.004) and fluoroscopy time in min (21.6±4.11 vs. 17.55±2.78, p=0.02) were more in Group I but the mean hemostasis time in min (7.58±1.11 vs. 15.59±3.33, p=0.005) and the ambulation time in hour (0.00±0.00 vs. 15.59±3.33, p=0.001) were more in Group II. Significant arterial spasm following puncture (10.0% vs. 0.0%, p=0.01) were more in Group I. Post procedural major bleeding (0.0% vs. 10.0%, p=0.004), minor bleeding (10.0% vs. 20.0%, p=0.004) were significant in Group II but vessel occlusion (5.0% vs. 0.0%, p=0.02) were significant in Group I. Transradial PCI is safe in respect of procedural and post procedural vascular complications. Transradial procedure leads to improved quality of life after the procedure and thus gives much comfort to the patient. It also shortened mean duration of hospital stay. So transradial approach is an attractive alternative to conventional transfemoral approach in the elderly.

Hypertriton Production in p-Pb Collisions at sqrt[s_{NN}]=5.02 TeV

The study of nuclei and antinuclei production has proven to be a powerful tool to investigate the formation mechanism of loosely bound states in high-energy hadronic collisions. The first measurement of the production of _{Λ}^{3}H in p-Pb collisions at sqrt[s_{NN}]=5.02  TeV is presented in this Letter. Its production yield measured in the rapidity interval -1<y<0 for the 40% highest-multiplicity p-Pb collisions is dN/dy=[6.3±1.8(stat)±1.2(syst)]×10^{-7}. The measurement is compared with the expectations of statistical hadronization and coalescence models, which describe the nucleosynthesis in hadronic collisions. These two models predict very different yields of the hypertriton in charged particle multiplicity environments relevant to small collision systems such as p-Pb, and therefore the measurement of dN/dy is crucial to distinguish between them. The precision of this measurement leads to the exclusion with a significance larger than 6.9σ of some configurations of the statistical hadronization model, thus constraining the theory behind the production of loosely bound states at hadron colliders.

Polarization of Λ and Λ[over ¯] Hyperons along the Beam Direction in Pb-Pb Collisions at sqrt[s]_{NN}=5.02 TeV

The polarization of the Λ and Λ[over ¯] hyperons along the beam (z) direction, P_{z}, has been measured in Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV recorded with ALICE at the Large Hadron Collider (LHC). The main contribution to P_{z} comes from elliptic flow-induced vorticity and can be characterized by the second Fourier sine coefficient P_{z,s2}=⟨P_{z}sin(2φ-2Ψ_{2})⟩, where φ is the hyperon azimuthal emission angle and Ψ_{2} is the elliptic flow plane angle. We report the measurement of P_{z,s2} for different collision centralities and in the 30%-50% centrality interval as a function of the hyperon transverse momentum and rapidity. The P_{z,s2} is positive similarly as measured by the STAR Collaboration in Au-Au collisions at sqrt[s_{NN}]=200  GeV, with somewhat smaller amplitude in the semicentral collisions. This is the first experimental evidence of a nonzero hyperon P_{z} in Pb-Pb collisions at the LHC. The comparison of the measured P_{z,s2} with the hydrodynamic model calculations shows sensitivity to the competing contributions from thermal and the recently found shear-induced vorticity, as well as to whether the polarization is acquired at the quark-gluon plasma or the hadronic phase.

Entropy Stabilization Effects and Ion Migration in 3D "Hollow" Halide Perovskites

A recently discovered new family of 3D halide perovskites with the general formula (A)_1-x(en)_x(Pb)_1-0.7x(X)_3-0.4x (A = MA, FA; X = Br, I; MA = methylammonium, FA = formamidinium, en = ethylenediammonium) is referred to as "hollow" perovskites owing to extensive Pb and X vacancies created on incorporation of en cations in the 3D network. The "hollow" motif allows fine tuning of optical, electronic, and transport properties and bestowing good environmental stability proportional to en loading. To shed light on the origin of the apparent stability of these materials, we performed detailed thermochemical studies, using room temperature solution calorimetry combined with density functional theory simulations on three different families of "hollow" perovskites namely en/FAPbI₃, en/MAPbI₃, and en/FAPbBr₃. We found that the bromide perovskites are more energetically stable compared to iodide perovskites in the FA-based hollow compounds, as shown by the measured enthalpies of formation and the calculated formation energies. The least stable FAPbI₃ gains stability on incorporation of the en cation, whereas FAPbBr₃ becomes less stable with en loading. This behavior is attributed to the difference in the 3D cage size in the bromide and iodide perovskites. Configurational entropy, which arises from randomly distributed cation and anion vacancies, plays a significant role in stabilizing these "hollow" perovskite structures despite small differences in their formation enthalpies. With the increased vacancy defect population, we have also examined halide ion migration in the FA-based "hollow" perovskites and found that the migration energy barriers become smaller with the increasing en content.

Measurement of the Groomed Jet Radius and Momentum Splitting Fraction in pp and Pb-Pb Collisions at sqrt[s_{NN}]=5.02 TeV

This article presents groomed jet substructure measurements in pp and Pb-Pb collisions at sqrt[s_{NN}]=5.02  TeV with the ALICE detector. The soft drop grooming algorithm provides access to the hard parton splittings inside a jet by removing soft wide-angle radiation. We report the groomed jet momentum splitting fraction, z_{g}, and the (scaled) groomed jet radius, θ_{g}. Charged-particle jets are reconstructed at midrapidity using the anti-k_{T} algorithm with resolution parameters R=0.2 and R=0.4. In heavy-ion collisions, the large underlying event poses a challenge for the reconstruction of groomed jet observables, since fluctuations in the background can cause groomed parton splittings to be misidentified. By using strong grooming conditions to reduce this background, we report these observables fully corrected for detector effects and background fluctuations for the first time. A narrowing of the θ_{g} distribution in Pb-Pb collisions compared to pp collisions is seen, which provides direct evidence of the modification of the angular structure of jets in the quark-gluon plasma. No significant modification of the z_{g} distribution in Pb-Pb collisions compared to pp collisions is observed. These results are compared with a variety of theoretical models of jet quenching, and provide constraints on jet energy-loss mechanisms and coherence effects in the quark-gluon plasma.

A Nanoscale Design Approach for Enhancing the Li-Ion Conductivity of the Li10GeP2S12 Solid Electrolyte

The discovery of the lithium superionic conductor Li10GeP2S12 (LGPS) has led to significant research activity on solid electrolytes for high-performance solid-state batteries. Despite LGPS exhibiting a remarkably high room-temperature Li-ion conductivity, comparable to that of the liquid electrolytes used in current Li-ion batteries, nanoscale effects in this material have not been fully explored. Here, we predict that nanosizing of LGPS can be used to further enhance its Li-ion conductivity. By utilizing state-of-the-art nanoscale modeling techniques, our results reveal significant nanosizing effects with the Li-ion conductivity of LGPS increasing with decreasing particle volume. These features are due to a fundamental change from a primarily one-dimensional Li-ion conduction mechanism to a three-dimensional mechanism and major changes in the local structure. For the smallest nanometric particle size, the Li-ion conductivity at room temperature is three times higher than that of the bulk system. These findings reveal that nanosizing LGPS and related solid electrolytes could be an effective design approach to enhance their Li-ion conductivity.

Evaluation of outcome of Coronavirus disease 2019 patients receiving RAAS inhibitors (OCRAS study): a prospective observational study of Bangladeshi hypertensive patients

Funding Acknowledgements

Type of funding sources: Private company. Main funding source(s): Beximco Pharmaceutical Limited, Bangladesh

OnBehalf

Cardiology Study Group (Bangladesh)

Background

The fact that SAARS-Cov2 virus enters cells through ACE2 receptors and the Renin-Angiotensin-Aldosterone System Inhibitors (RAASi) upregulate the ACE2 receptors, there was speculation that use of RAASi may lead increased cellular entry of the virus.  There was a pause for a brief period of the use of RAASi in COVID 19 patients. But clinically the speculation has been found to be incorrect. Different professional societies come up with the assertion to continue to use RAASi. As the hesitancy among the clinicians appears to continue and there is no first hand data regarding the safety of the use of RAASi in Bangladeshi population, the study was undertaken to evaluate the safety of RAASi in COVID 19 patients.

Aims & Methods

This study was a prospective, observational multi-center study to evaluate the outcome of COVID-19 patients receiving RAAS inhibitors. Adult Hypertensive patients (age ≥18 years) with diagnosed COVID-19 confirmed by RT-PCR test who have a history of taking either ACE inhibitor/ARB or any other anti-hypertensive medication. Evaluation of outcome was assessed by rate of hospitalization, requirement of oxygen therapy, requirement of high flow nasal cannula, admission to ICU and mortality between two groups. All statistical analyses were performed using SPSS for Windows, version 20.0 (SPSS Inc., Chicago, IL, USA).

Results

We collected data from 147 Covid-19 positive patients confirmed by RT-PCR. Among them, 117 (79.6%) had a history of taking RAAS inhibitor and 30 had history of taking other antihypertensive medications. Of them, two-third patients had more than 50 years of age and more than half of the patients had overweight or obesity. Other than hypertension they had several comorbidities such as Diabetes Mellitus (45.4%), Ischemic Heart Diseases (35.4%), Asthma or COPD (15%) etc. Rate of hospitalization had no statistical difference between RAAS inhibitor group and other hypertensive group (48.7% vs 46.70% respectively; p-value - 0.841). There was no statistical difference between two groups in terms of requirement of oxygen therapy (p-value - 0.297), High Flow Nasal Cannula (p-value - 0.430), intensive care unit (p-value - 0.194) and death (p-value – 0.383) also. Almost half and one-third of the patients had persistence of symptoms even after 14 days and 28 days respectively. Fatigue, cough, breathlessness, loss of appetite and taste were the most common symptoms among those.

Conclusion

In our study we found that RAAS inhibitor treatment had no adverse effect on the outcome of COVID-19 patients compared with other antihypertensive drugs. Patients may continue receiving ACEIs and ARBs for the treatment of any indication for RAASi without an increased risk of worse outcomes.

Measurement of Prompt D^{0}, Λ_{c}^{+}, and Σ_{c}^{0,++}(2455) Production in Proton-Proton Collisions at sqrt[s]=13 TeV

The p_{T}-differential production cross sections of prompt D^{0}, Λ_{c}^{+}, and Σ_{c}^{0,++}(2455) charmed hadrons are measured at midrapidity (|y|<0.5) in pp collisions at sqrt[s]=13  TeV. This is the first measurement of Σ_{c}^{0,++} production in hadronic collisions. Assuming the same production yield for the three Σ_{c}^{0,+,++} isospin states, the baryon-to-meson cross section ratios Σ_{c}^{0,+,++}/D^{0} and Λ_{c}^{+}/D^{0} are calculated in the transverse momentum (p_{T}) intervals 2<p_{T}<12 and 1<p_{T}<24  GeV/c. Values significantly larger than in e^{+}e^{-} collisions are observed, indicating for the first time that baryon enhancement in hadronic collisions also extends to the Σ_{c}. The feed-down contribution to Λ_{c}^{+} production from Σ_{c}^{0,+,++} is also reported and is found to be larger than in e^{+}e^{-} collisions. The data are compared with predictions from event generators and other phenomenological models, providing a sensitive test of the different charm-hadronization mechanisms implemented in the models.