bluuebunny/crossref_metadata_2025 huggingface dataset:
HFIP-Induced Allylation Reaction of Tertiary Allylic Alcohols with Thiols or Sulfonyl Hydrazines to Access Allylic Organosulfurs
Authors: Tong Qing-Xiao , Zhong Jian-Ji , Lu Maojian , Zhang Rong-Jin , Zhu Can-Ming , Xiao Yonghong , Chen Jian-Rui , Zhao Lei-Min
Published: August 2022

A simple and transition-metal-free HFIP-induced allylation reaction of tertiary allylic alcohols with thiols or sulfonyl hydrazine derivatives was reported for the efficient and highly selective synthesis of allylic sulfides and allylic sulfones. Herein, HFIP played a vital role in not only activating the allylic alcohol, but also stabilizing the allylic cation intermediate to accelerate the subsequent transformations.
Comparative Effectiveness of Pre-Identified Homeopathic Medicines in Asymptomatic COVID-19 Individuals Receiving Standard Care—An Open-Label, Randomized, Controlled Exploratory Trial
Authors: Varanasi Roja , Tomar Sunita , Gupta Sanjay , Jaiswal Praveen , Srivastava Ankit , Parmar Vijendra , Chauhan Shradha , Kumar Arvind , Mishra Shivendra Kumar , Khurana Anil
Published: August 2022

Background Asymptomatic COVID-19 subjects can transmit the infection for as many as 14 days and are regarded as a significant factor in the rapid spread of the COVID-19 pandemic. This exploratory study aimed to determine any additional benefits of selected homeopathic medicines compared with placebo in asymptomatic COVID-19 individuals receiving standard care.

Methods This open-label, randomized, placebo-controlled, exploratory trial was undertaken at a COVID Care Centre (CCC) in Madhya Pradesh, India. Patients (n = 200, 18–65 years, both sexes) having a positive RT-PCR and asymptomatic during admission were enrolled. They were randomly assigned to one of four groups (each n = 50): Arsenicum album 30C (Ars. alb.), Camphora 1M (Camph.), Bryonia alba 30C (Bry. alb.) and placebo (Pl.). All the patients were given standard care. The primary outcome was the number of patients becoming RT-PCR negative for SARS-CoV-2 at days 5, 10 and 15.

Results In total, 200 asymptomatic COVID-19 patients were enrolled. One hundred and seventy-seven patients became RT-PCR negative by day 15; 88%, 80%, 98% and 88% from Ars. alb., Camph., Bry. alb. and Pl. respectively. A Chi-square test of association for the total patients who became RT-PCR negative for SARS-Cov-2 in each group showed a marginal statistical significance (Chi-square: 8.1, p = 0.04). A two-proportion Z-test comparing each pre-identified homeopathic medicine with placebo showed marginal statistical significance (p = 0.05) for Bry alb. only. Median time in days to RT-PCR negative (Kaplan Meier analysis) was 10 days in each of the groups.

Conclusion There was some evidence that, compared with Ars alb., Camph. or Pl., Bry. alb. was associated with an increased number of patients who became RT-PCR negative for COVID-19 by day 15. The possible effect exerted needs to be investigated in additional research.
Computed Tomography Evaluation of the Paranasal Sinuses in Adults with Primary Ciliary Dyskinesia
Authors: Plantier Diogo Barreto , Pilan Renata R. M. , Athanazio Rodrigo , Olm Mary Anne K. , Gebrim Eloisa M. S. , Voegels Richard Louis
Published: August 2022

Introduction Primary ciliary dyskinesia is a rare inherited disease that results in a malfunction of mucociliary clearance and sinonasal complaints. Aplasia/hypoplasia of the frontal and sphenoid sinuses has been described as more frequent in this population. However, to date, no studies have provided a detailed description of computed tomography findings in adult patients with a diagnosis of this condition.

Objective To describe the computed tomography (CT) findings of adult patients with primary ciliary dyskinesia.

Methods Retrospective observational study of adult patients with primary ciliary dyskinesia who underwent CT.

Results Twenty-one adults were included in the study. Aplasia occurred in 38.1% of frontal sinuses and in 14.3% of sphenoid sinuses. Likewise, hypoplasia occurred in 47.6% of the frontal sinuses, in 54.8% of the sphenoid sinuses and in 40.5% of the maxillary sinuses. Furthermore, trabecular loss was identified in 61.9% ethmoidal sinuses. The mean Lund-Mackay score was 13.5. In addition, 9.5% of the patients had concha bullosa, 47.6% had marked bilateral inferior turbinate hypertrophy, 38.1% had marked middle turbinate hypertrophy, and 47.6% had marked septal deviation. Finally, we identified images suggestive of fungus ball, mucocele, osteoma, a possible antrochoanal polyp, and frontal bone erosions.

Conclusion The present study provides a detailed description of CT findings in patients with primary ciliary dyskinesia. We also describe abnormalities that must be identified for safer surgical planning and that suggest a diagnosis of primary ciliary dyskinesia if found in patients with a consistent clinical picture.
Oral Health Status of Illicit Drug Users in a Health District in South Africa
Authors: Mukhari-Baloyi Ntsakisi , Bhayat Ahmed , Madiba Thomas K. , Nkambule Ntombizodwa R.
Published: August 2022

Objectives The prevalence of illicit drug use and its associated oral health complications have been increasing in South Africa (SA). There has been a paucity of studies to determine the oral health status among illicit drug users in SA. This study aimed to determine the oral health knowledge, practices, and status of illicit drug users at rehabilitation centers in a district in SA.

Materials and Methods This was a cross-sectional study conducted at four rehabilitation centers in Pretoria, SA. Data were collected using a validated self-administered questionnaire and an oral examination. The questionnaire consisted of three parts: demographics, oral health knowledge, and oral health practices. The oral examination was conducted by a calibrated researcher and included caries, periodontal status, dental erosion, trauma, and soft tissue lesions.

Statistical Analysis The data were analyzed using the Statistical Package for Social Sciences (SPSS) software.

Results The mean age was 25.5 (±7.49) years with 91% being male. The majority (84%) of patients were Black, and almost all (87%) had never received oral health education; 55% were not aware that illicit drugs could have an impact on the oral health status and 40% had never had a prior dental consultation. The caries prevalence was 68% with a mean decayed, missing and filled teeth (DMFT) score of 5.3 (±6.18). More than half (58%) required periodontal treatment and there were minimal soft and hard tissue lesions diagnosed. Those who perceived their teeth to be in a poor condition had a significantly higher Decayed, Missing and Filled Teeth (DMFT) score compared with those who perceived their oral health to be good. Just under half (41.9%) of the participants did not need any periodontal intervention, with the other half presenting with plaque retention or calculus and thus needed oral hygiene intervention inclusive of scaling and polishing. There was minimal evidence of pathological oral lesions with only 1.5% presenting with necrotizing periodontal disease (NPD). Overall, there was generalized poor oral hygiene

Conclusion Many of the participants had poor oral hygiene knowledge and practices and a relatively high prevalence of caries. It is imperative that oral health promotion and education is incorporated into the medical interventions provided at rehabilitation centers.
Preliminary Report from a Randomized Controlled Trial Comparing Two Bovine Pericardial Valves
Authors: Sohn Suk Ho , Kim Ji Seong , Choi Jae Woong , Lee Jae Hang , Kim Jun Sung , Lim Cheong , Hwang Ho Young
Published: August 2022

Background A randomized controlled trial was designed to compare 1-year hemodynamic profiles and clinical outcomes after bioprosthetic aortic valve replacement (AVR) using a recently introduced (study group) and world-widely used (control group) bovine pericardial bioprostheses. This study evaluated early postoperative outcomes as a preliminary analysis.

Methods The primary end point of the trial was the mean pressure gradient across the aortic valve (AVMPG) at 1 year after surgery. Patients were screened to enroll 70 patients in each group based on a noninferiority design. Early postoperative hemodynamic and clinical outcomes were compared between the two groups.

Results There were no differences in baseline characteristics, including sex and body surface area (1.64 ± 0.18 vs. 1.65 ± 0.15 m2) between the two groups. The AVMPG on early postoperative echocardiography was 15.2 ± 4.6 mm Hg and 16.5 ± 6.2 mm Hg in the study and control groups, respectively (p = 0.177). Although AVMPG of the 19 mm prostheses was lower in the study group than in the control group (17.0 ± 6.3 mm Hg vs. 22.8 ± 6.6 mm Hg, p = 0.039), there were no significant differences in the effective orifice area in all patients (1.57 ± 0.41 cm2 vs. 1.53 ± 0.34 cm2, p = 0.568), and each valve size. The effective orifice area index was also similar between the two groups in overall (p = 0.352), and in each valve size. There were no significant differences in clinical outcomes including operative mortality and postoperative complications between the two groups.

Conclusion Early postoperative hemodynamic and clinical results after AVR using a recently introduced bovine pericardial valve were comparable with those using the control valve (NCT03796442)
Impact of Procedure Volume on the Outcomes of Surgical Aortic Valve Replacement
Authors: Oettinger Vera , Kaier Klaus , von zur Mühlen Constantin , Zehender Manfred , Bode Christoph , Beyersdorf Friedhelm , Stachon Peter , Bothe Wolfgang
Published: August 2022

Background Literature demonstrated that procedure volumes affect outcomes of patients undergoing transcatheter aortic valve implantation. We evaluated the outcomes of surgical aortic valve replacement.

Methods All isolated surgical aortic valve replacement procedures in Germany in 2017 were identified. Hospitals were divided into five groups from ≤25 (very low volume) until >100 (very high volume) annual procedures.

Results In 2017, 5,533 patients underwent isolated surgical aortic valve replacement. All groups were of comparable risk (logistic EuroSCORE, 5.12–4.80%) and age (66.6–68.1 years). In-hospital mortality and complication rates were lowest in the very high-volume group. Multivariable logistic regression analyses showed no significant volume–outcome relationship for in-hospital mortality, stroke, postoperative delirium, and mechanical ventilation > 48 hours. Regarding acute kidney injury, patients in the very high-volume group were at lower risk than those in the very low volume group (odds ratio [OR] = 0.53, p = 0.04). Risk factors for in-hospital mortality were previous cardiac surgery (OR = 5.75, p < 0.001), high-grade renal disease (glomerular filtration rate < 15 mL/min, OR = 5.61, p = 0.002), surgery in emergency cases (OR = 2.71, p = 0.002), and higher grade heart failure (NYHA [New York Heart Association] III/IV; OR = 1.80, p = 0.02). Risk factors for all four complication rates were atrial fibrillation and diabetes mellitus.

Conclusion Patients treated in very low volume centers (≤25 operations/year) had a similar risk regarding in-hospital mortality and most complications compared with very high-volume centers (>100 operations/year). Only in the case of acute kidney injury, very high-volume centers showed better outcomes than very low volume centers. Therefore, surgical aortic valve replacement can be performed safely independent of case volume.
Modified Michelson interferometer offers promise for short-range gravity experimentation
Authors: Ikenson Ben
Published: August 2022

Proof of concept interferometer measures angular deflection and pendulum twist
Metal contacts with Moire interfaces on WSe2 for ambipolar applications
Authors: Chen Jiaqi , Zhang Zhaofu , Guo Yuzheng , Robertson John
Published: August 2022

The rational design of metal contacts on transition metal dichalcogenides can significantly improve the performance of 2D devices. We have previously shown that a Moire interface between n-type monolayer MoS2 and metal contacts enhances the stability of physisorptive interface sites, thereby enabling weaker Fermi level pinning and allowing easier variation of the Schottky barrier height at these interfaces. We extend these calculations to p-type and ambipolar WSe2 contacts in this work. The analysis shows that the Moire interfaces again have a weaker Fermi level pinning, while most metals have chemisorptive sites with stronger pinning. We find that the most stable site of Pd is a Moire site with an unusually low p-type Schottky barrier height (p-SBH), while Au has a metastable low p-SBH. In and Al retain their low n-type SBHs, which together with Pd enable ambipolar contacts by the choice of contact metals, indicating that WSe2 can be used for high-performance ambipolar devices with the rational design of contact metals.
Structural and electrostatic properties between pH-responsive polyelectrolyte brushes studied by augmented strong stretching theory
Authors: Sin Jun-Sik
Published: August 2022

In this paper, we study electrostatic and structural properties between pH-responsive polyelectrolyte brushes by using a strong stretching theory accounting for excluded volume interactions, the density of polyelectrolyte chargeable sites, and the Born energy difference between the inside and outside of the brush layer. In a free energy framework, we obtain self-consistent field equations to determine electrostatic properties between two pH-responsive polyelectrolyte brushes. We elucidate that in the region between two pH-responsive polyelectrolyte brushes, electrostatic potential at the centerline and osmotic pressure increase not only with excluded volume interaction but also with the density of chargeable sites on a polyelectrolyte molecule. Importantly, we clarify that when two pH-responsive polyelectrolyte brushes approach each other, the brush thickness becomes short and that a large excluded volume interaction and a large density of chargeable sites yield the enhanced contract of polyelectrolyte brushes. In addition, we also demonstrate how the influence of such quantities as pH, the number of Kuhn monomers, the density of charged sites, the lateral separation between adjacent polyelectrolyte brushes, and Kuhn length on the electrostatic and structural properties between the two polyelectrolyte brushes is affected by the exclusion volume interaction. Finally, we investigate the influence of the Born energy difference on the thickness of polyelectrolyte brushes and the osmotic pressure between two pH-responsive polyelectrolyte brushes.
Chiral Berry plasmon dispersion of the two-dimensional electron gas based on a quantum hydrodynamic model
Authors: Wang Baojun , Guo Bin
Published: August 2022

We employ the quantum hydrodynamic model to investigate the properties of chiral Berry plasmons (CBPs) generated by a high-density two-dimensional electron gas (2DEG) film covering a semi-infinite dielectric substrate with a finite Berry flux. By coupling Maxwell's equations, Poisson's equation, and the boundary conditions, we derive the dispersion relations of plasmon with a nonzero Berry flux in detail. We present the difference in the dispersion of CBPs with quantum effects and the classical model. We show how the quantum effect, Berry curvature, the dielectric constant of the substrate, and electron density in 2DEG affect the behavior of the CBPs. Parameter dependence of the effects is calculated and discussed.
Impact of A2T and D23N mutations on C99 homodimer conformations
Authors: Lu Yan , Salsbury Freddie R. , Derreumaux Philippe
Published: August 2022

The proteolytic cleavage of C99 by γ-secretase is the last step in the production of amyloid-β (Aβ) peptides. Previous studies have shown that membrane lipid composition, cholesterol concentration, and mutation in the transmembrane helix modified the structures and fluctuations of C99. In this study, we performed atomistic molecular dynamics simulations of the homodimer of the 55-residue congener of the C-terminal domain of the amyloid protein precursor, C99(1–55), in a 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine-cholesterol lipid bilayer and compared the conformational ensemble of wild-type (WT) sequence to those of the A2T and D23N variants. These mutations are particularly interesting as the protective Alzheimer’s disease (AD) A2T mutation is known to decrease Aβ production, whereas the early onset AD D23N mutation does not affect Aβ production. We found noticeable differences in the structural ensembles of the three sequences. In particular, A2T varies from both WT and D23N by having long-range effects on the population of the extracellular juxtamembrane helix, the interface between the G29xxx-G33xxx-G37 motifs, and the fluctuations of the transmembrane helical topologies.
Natural frequencies of a bubble near a solid sphere
Authors: Liu Bo , Bhattacharya Sukalyan
Published: August 2022

This paper presents an analytical and computational method to describe natural frequencies of a spherical bubble residing near a solid sphere of an arbitrary size in an otherwise unbounded fluid. Under low capillary and Reynolds number limits, the relevant hydrodynamic fields are converted into time-invariant but frequency-dependent quantities by temporal Fourier transform. Then, the spatial variations in the velocity and the pressure can be expressed in terms of two sets of harmonic basis functions involving spherical coordinates centered around the particle and the bubble. A subsequent derivation of transformation coefficients between the aforementioned two sets allows a matrix equation relating the unknown amplitudes to the boundary conditions at all interfaces. Finally, natural frequencies corresponding to different modes of pulsation are obtained from the eigenvalues of the constructed matrix. The results show fast convergence of the computed frequencies with the increasing number of basis functions. These values change significantly with the distance of the bubble from the particle and even decay to zero for some modes when their surface-to-surface separation vanishes. Furthermore, bubble oscillation near a solid plate is also discussed when the radius of the solid sphere is increased to an infinitely large dimension. Thus, this article renders a comprehensive study of naturally pulsating submerged bubbles in the presence of a nearby solid surface of various kinds.
Dissociative multi-ionization of N2O molecules in strong femtosecond laser field
Authors: Jiang Wenbin , Wang Xincheng , Zhang Shuai , Dong Ruichao , Guo Yuliang , Feng Jinze , Shen Zhenjie , Yan Tianmin , Zhu Zhiyuan , Jiang Yuhai
Published: August 2022

Multi-ionization and subsequent Coulomb explosion (CE) of the N2O molecule irradiated by a linearly polarized 800 nm laser field is investigated by a reaction microscope, where a number of CE channels of N2Oq+ with q ≤ 5 for two-body fragmentation and q ≤ 8 for three-body fragmentation were observed. For two-body CE, by analyzing the internuclear separations extracted from kinetic energy releases (KERs), dissociation branching fractions, and laser intensity dependence, interestingly, we found that fragmentation N2O5+ → N3+ + NO2+ is produced directly from dissociating N2O3+ via non-sequential stairstep ionization, whereas most of the others result from the sequential stairstep ionization. For three-body CE, 25 fragmentation channels of N2Oq+ (q = 3–8) are distinguished in the present charge-encoded multi-photoion coincidence plot, and the concerted fragmentation mechanism is nominated in a typical Dalitz plot. With the help of the numerical computation with the measured KERs and momentum correlation angles, the geometric structures of molecular ions prior to fragmentation are reconstructed, which display the bending motion and simultaneous two-bond stretching before the CE. Increasing of the bond length for high charged N2Oq+ indicates the dominating stairstep ionization in the three-body fragmentation.
Range-dependence of two-body intermolecular interactions and their energy components in molecular crystals
Authors: Metcalf Derek P. , Smith Andrew , Glick Zachary L. , Sherrill C. David
Published: August 2022

Routinely assessing the stability of molecular crystals with high accuracy remains an open challenge in the computational sciences. The many-body expansion decomposes computation of the crystal lattice energy into an embarrassingly parallel collection of computations over molecular dimers, trimers, and so forth, making quantum chemistry techniques tractable for many crystals of small organic molecules. By examining the range-dependence of different types of energetic contributions to the crystal lattice energy, we can glean qualitative understanding of solid-state intermolecular interactions as well as practical, exploitable reductions in the number of computations required for accurate energies. Here, we assess the range-dependent character of two-body interactions of 24 small organic molecular crystals by using the physically interpretable components from symmetry-adapted perturbation theory (electrostatics, exchange-repulsion, induction/polarization, and London dispersion). We also examine correlations between the convergence rates of electrostatics and London dispersion terms with molecular dipole moments and polarizabilities, to provide guidance for estimating convergence rates in other molecular crystals.
How do we drive a renaissance for national island conservation in Australia?
Authors: Ball Derek , Moro Dorian , Bock Ellie , Bryant Sally L.
Published: August 2022

Australia’s approach to managing and conserving its offshore islands as important national assets warrants urgent review. There is a growing realisation that the current trajectory of loss of natural heritage on islands must be reversed, particularly in an era of increasing climate change. We propose a role description and an organisational model for a national Australian Islands Alliance that champions conservation action, prioritises investments aligned to risks, and that connects partners at a strategic national level. A national alliance offers important opportunity to assess threats and report on condition. Four key foundations underpin a national alliance dedicated to championing island care and expert management: (1) management informed by evidence; (2) sound return on investment; (3) national coordination in partnership with States and Territories; and (4) community participation inclusive of Aboriginal peoples’ and Torres Strait Islanders’ custodial rights and interests. The message from experiences shared across Australia, New Zealand and the Pacific region is that traditional island custodians and stakeholders are vital partners to restoration efforts. These shared learnings collectively demonstrate the time is now for Australia to move forward with a respectful and unified direction to progress successful and sustainable island conservation and restoration.
Delayed pressure urticaria manifesting as dyspareunia – is it that uncommon?
Authors: Konstantinou George N. , Podder Indrashis
Published: August 2022

Delayed pressure urticaria (DPU) is a variant of physical urticaria characterised by reproducible whealing on application of sustained pressure to the skin. Clinical manifestations include delayed cutaneous erythema, edema and subcutaneous swelling, typically occurring 4–6 h after application of mechanical pressure. Dyspareunia is defined as persistent or recurrent pain in the genital area or within the pelvis that occurs just before, during, or after sexual intercourse. We report an unusual case of DPU manifesting as dyspareunia.
COVID-19 infection induces higher trust in strangers
Authors: Gambetta Diego , Morisi Davide
Published: August 2022

How does the COVID-19 pandemic affect interpersonal trust? Most evidence shows that natural disasters reinforce trust and cooperation, but the COVID-19 virus differs from other calamities, since it spreads through contact with people, potentially increasing suspicion and distrust, as, according to contemporaneous writers’ accounts, seems to have been the case with the Black Death, the London plague, and the Spanish influenza. We investigate the link between interpersonal trust and individuals exposed to COVID-19, either vicariously through their community or networks or directly by becoming infected. We rely on an original panel survey, including a survey experiment, with a representative sample of adults in Italy, one of the countries hardest struck by the pandemic. Our experimental findings reveal that priming people about the risk that the pandemic poses to their health leads to a substantial increase in their trust in strangers. Our panel data analysis of within-individual effects shows that those who become infected trust strangers more than those who are not infected. Our findings could be explained by people observing higher than expected altruistic behavior or becoming more dependent on other people’s support, consistent with the “emancipation theory of trust.” When people recover from COVID-19, however, they drop to trusting strangers as much as those who were not directly exposed to the virus, an indication that the positive effects on trust during the pandemic have an emotional source. Nonetheless, the evidence suggests that, in the aggregate, there has been a small but significant increase in trust among the general population relative to prepandemic levels.
Recurrent droughts increase risk of cascading tipping events by outpacing adaptive capacities in the Amazon rainforest
Authors: Wunderling Nico , Staal Arie , Sakschewski Boris , Hirota Marina , Tuinenburg Obbe A. , Donges Jonathan F. , Barbosa Henrique M. J. , Winkelmann Ricarda
Published: August 2022

Tipping elements are nonlinear subsystems of the Earth system that have the potential to abruptly shift to another state if environmental change occurs close to a critical threshold with large consequences for human societies and ecosystems. Among these tipping elements may be the Amazon rainforest, which has been undergoing intensive anthropogenic activities and increasingly frequent droughts. Here, we assess how extreme deviations from climatological rainfall regimes may cause local forest collapse that cascades through the coupled forest–climate system. We develop a conceptual dynamic network model to isolate and uncover the role of atmospheric moisture recycling in such tipping cascades. We account for heterogeneity in critical thresholds of the forest caused by adaptation to local climatic conditions. Our results reveal that, despite this adaptation, a future climate characterized by permanent drought conditions could trigger a transition to an open canopy state particularly in the southern Amazon. The loss of atmospheric moisture recycling contributes to one-third of the tipping events. Thus, by exceeding local thresholds in forest adaptive capacity, local climate change impacts may propagate to other regions of the Amazon basin, causing a risk of forest shifts even in regions where critical thresholds have not been crossed locally.
Influence of the drawing process on corrosion behaviour of hot-dip galvanised wires
Authors: Suliga Maciej , Wartacz Radosław , Hawryluk Marek
Published: August 2022

The phenomenon of corrosion on wires and springs covered with an anti-corrosive zinc coating was investigated. To assess the corrosion resistance of galvanised wires, tests were carried out in the standard neutral salt spray corrosion test and in the sulphur dioxide test with general moisture condensation. The spring corrosion process depends on the wire drawing technology. The research showed that the higher the drawing speed and angle, the more dynamic the corrosion development.
Performance analysis of synthetic jet micropump based on double piezoelectric actuators
Authors: Hu Dianbin , He Lipeng , Hu Renhui , Hou Yi , Liu Yamei , Cheng Guangming
Published: August 2022

To alleviate the problem of low flow rates of synthetic jet piezoelectric pumps for liquid medium, a double piezoelectric synthetic jet micropump (DPSJM) is proposed. DPSJM generates pressure change in the pump chamber by the high voltage vibration of the double piezoelectric actuators. Theoretical models are used to analyze the factors affecting the performance of DPSJM. The flow field is analyzed by using the finite element method in the jet chamber, and the prototype is built and tested. The results show that the performance of the DPSJM is best with double piezoelectric actuators with a sine wave drive signal and a pump chamber height of 1 mm. The highest flow rate comes to 22.11 ml min−1 at 175 V, 65 Hz. Moreover, the DPSJM is simple in construction. When compared to other types of valveless piezoelectric pumps, there was no resistance fluid in the pump chamber, which could significantly reduce the damage to the transfer medium.
Unfolding the conductivity reversal n- to p-type in phosphorus-doped ZnO thin films by spin-on dopant (SOD) process
Authors: Mishra Madhuri , Saha Rajib , Bhowmick Sangita , Pandey Sushil Kumar , Chakrabarti Subhananda
Published: August 2022

Phosphorus doping induced p-type doping in ZnO thin films based on spin-on dopant (SOD) process is reported in this article. Owing to the reduced dependence on the conventional amenities for diffusion/ion-implantation doping, the SOD process provides a simple and cheap doping method. The effect of SOD process temperature on conductivity ZnO thin films is investigated by altering the temperature from 700°C to 1000°C. Systematic field emission scanning electron microscopy analysis demonstrates the impact of doping temperature on the morphological properties of SOD. The x-ray diffraction measurements reveal that the p-type ZnO thin films had (002) preferred crystal orientation. At the same time, x-ray photoelectron spectroscopy validated the formation of the PZn–2VZn complex, which was responsible for the acceptor behaviour of films. Moreover, the photoluminescence spectra tracked down that the origin of 3.35 and 3.31 eV emission peaks is due to the acceptor bound exciton and free-electron to acceptor level transitions, respectively. Finally, an elevated hole concentration of 2.09 × 1016 cm−3 is achieved with a resistivity of 1.14 Ω-cm at 800°C doping temperature. However, the film doped at 900°C and 1000°C showed n-type behaviour due to the generation of high concentration donor defects. Here, we successfully demonstrate that the SOD process has great potential to produce high-quality p-type ZnO thin films suitable for optoelectronic devices applications.
Intrinsic dipole-induced self-doping in Janus MXY-based (M = Mo, W; X = S; Y = Se, Te) p–n junctions
Authors: Xiao Kun-Xing , Si Yuan , Yang Ke , Lian Ji-Chun , Huang Tao , Peng Wei , Huang Gui-Fang , Hu Wangyu , Huang Wei-Qing
Published: August 2022

Semiconductor p–n junctions are the most rudimentary building block in modern optoelectronic devices. Herein, we report and demonstrate, using first-principle calculations, that an intrinsic dipole induces self-doping in Janus MXY (M = Mo, W; X = S; Y = Se, Te) van der Waals p–n junctions. The stacked dipole moment in Janus MXY homostructures drives the electrons and holes transfer, forming self-doped p-type and n-type regions in the outermost layer, which is in stark distinction from previously applied electric fields. Furthermore, the doping level in G/MXY/G (G = graphene) heterostructures can be modulated by tuning the thickness of the Janus MXY. Taking the G/WSTe/G heterostructure as an example, the charge carrier density could be tunable to

6.3
×

10

13

c

m

−

2

when the Janus WSTe thickness is stacked to a double layer. Interestingly, the interface dipole moment caused by the electrons transfer results in an asymmetric doping level in the top graphene and bottom graphene. Our work provides an intrinsic approach for designing self-doped p–n junctions.
Elasticity versus phase field driven motion in the phase field crystal model
Authors: Acharya Amit , Angheluta Luiza , Viñals Jorge
Published: August 2022

The inherent inconsistency in identifying the phase field in the phase field crystal theory with the material mass and, simultaneously, with material distortion is discussed. In its current implementation, elastic relaxation in the phase field crystal occurs on a diffusive time scale through a dissipative permeation mode. The very same phase field distortion that is included in solid elasticity drives diffusive motion, resulting in a non physical relaxation of the phase field crystal. We present two alternative theories to remedy this shortcoming. In the first case, it is assumed that the phase field only determines the incompatible part of the elastic distortion, and therefore one is free to specify an additional compatible distortion so as to satisfy mechanical equilibrium at all times (in the quasi static limit). A numerical solution of the new model for the case of a dislocation dipole shows that, unlike the classical phase field crystal model, it can account for the known law of relative motion of the two dislocations in the dipole. The physical origin of the compatible strain in this new theory remains to be specified. Therefore, a second theory is presented in which an explicit coupling between independent distortion and phase field accounts for the time dependence of the relaxation of fluctuations in both. Preliminary details of its implementation are also given.
Computational approaches to model X-ray photon correlation spectroscopy from molecular dynamics
Authors: Mohanty Shaswat , Cooper Christopher B , Wang Hui , Liang Mengning , Cai Wei
Published: August 2022

X-ray photon correlation spectroscopy (XPCS) allows for the resolution of dynamic processes within a material across a wide range of length and time scales. X-ray speckle visibility spectroscopy (XSVS) is a related method that uses a single diffraction pattern to probe ultrafast dynamics. Interpretation of the XPCS and XSVS data in terms of underlying physical processes is necessary to establish the connection between the macroscopic responses and the microstructural dynamics. To aid the interpretation of the XPCS and XSVS data, we present a computational framework to model these experiments by computing the X-ray scattering intensity directly from the atomic positions obtained from molecular dynamics simulations. We compare the efficiency and accuracy of two alternative computational methods: the direct method computing the intensity at each diffraction vector separately, and a method based on fast Fourier transform that computes the intensities at all diffraction vectors at once. The computed X-ray speckle patterns capture the density fluctuations over a range of length and time scales and are shown to reproduce the known properties and relations of experimental XPCS and XSVS for liquids.
Nanostructure MoS2 electrocatalyst modified large area carbon electrode for efficient hydrogen evolution
Authors: Gupta Jyoti , Das Dibakar , Karati Anirudha , Joardar Joydip , Borse Pramod H
Published: August 2022

Hydrothermally synthesized nanostructured MoS2 was immobilized over large area graphite paper (5 × 5 mm2) to fabricate electrode for hydrogen evolution application. The chemical optimization via. variation in hydroxylamine hydrochloride(HAH) concentration, led to nanosheets containing surface over the micro-balls, with a 1T and 2H phase of MoS2. A physicochemical and electrochemical characterization yielded a lowest Tafel slope of ∼67 mV dec−1, a lowest over potential of 0.19 V with a significant electrocatalytic stability in acidic. An electrocatalytic hydrogen evolution over optimized MoS2 evolved 2 times (∼46 μmol h−1) of hydrogen gas as compared to that from MoS2 synthesized without HAH. The improved performance of electrocatalyst can be attributed to the combination of phase, and electrochemical properties 2D structure of MoS2.
Preferential modulation of individual retinal ganglion cells by electrical stimulation
Authors: Yunzab Molis , Soto-Breceda Artemio , Maturana Matias , Kirkby Stephanie , Slattery Maximilian , Newgreen Anton , Meffin Hamish , Kameneva Tatiana , Burkitt Anthony N , Ibbotson Michael , Tong Wei
Published: August 2022

Objective. Retinal prostheses have had limited success in vision restoration through electrical stimulation of surviving retinal ganglion cells (RGCs) in the degenerated retina. This is partly due to non-preferential stimulation of all RGCs near a single stimulating electrode, which include cells that conflict in their response properties and their contribution to visiual processing. Our study proposes a stimulation strategy to preferentially stimulate individual RGCs based on their temporal electrical receptive fields (tERFs). Approach. We recorded the responses of RGCs using whole-cell patch clamping and demonstrated the stimulation strategy, first using intracellular stimulation, then via extracellular stimulation. Main results. We successfully reconstructed the tERFs according to the RGC response to Gaussian white noise current stimulation. The characteristics of the tERFs were extracted and compared based on the morphological and light response types of the cells. By re-delivering stimulation trains that were composed of the tERFs obtained from different cells, we could preferentially stimulate individual RGCs as the cells showed lower activation thresholds to their own tERFs. Significance. This proposed stimulation strategy implemented in the next generation of recording and stimulating retinal prostheses may improve the quality of artificial vision.
Aeroelastic characterisation of a bio-inspired flapping membrane wing
Authors: Gehrke Alexander , Richeux Jules , Uksul Esra , Mulleners Karen
Published: August 2022

Natural fliers like bats exploit the complex fluid–structure interaction between their flexible membrane wings and the air with great ease. Yet, replicating and scaling the balance between the structural and fluid-dynamical parameters of unsteady membrane wings for engineering applications remains challenging. In this study, we introduce a novel bio-inspired membrane wing design and systematically investigate the fluid–structure interactions of flapping membrane wings. The membrane wing can passively camber, and its leading and trailing edges rotate with respect to the stroke plane. We find optimal combinations of the membrane properties and flapping kinematics that out-perform their rigid counterparts both in terms of increased stroke-average lift and efficiency, but the improvements are not persistent over the entire input parameter space. The lift and efficiency optima occur at different angles of attack and effective membrane stiffnesses which we characterise with the aeroelastic number. At optimal aeroelastic numbers, the membrane has a moderate camber between 15% and 20% and its leading and trailing edges align favourably with the flow. Higher camber at lower aeroelastic numbers leads to reduced aerodynamic performance due to negative angles of attack at the leading edge and an over-rotation of the trailing edge. Most of the performance gain of the membrane wings with respect to rigid wings is achieved in the second half of the stroke when the wing is decelerating. The stroke-maximum camber is reached around mid-stroke but is sustained during most of the remainder of the stroke which leads to an increase in lift and a reduction in power. Our results show that combining the effect of variable stiffness and angle of attack variation can significantly enhance the aerodynamic performance of membrane wings and has the potential to improve the control capabilities of micro air vehicles.
Universal framework for the long-time position distribution of free active particles
Authors: Santra Ion , Basu Urna , Sabhapandit Sanjib
Published: August 2022

Active particles self-propel themselves with a stochastically evolving velocity, generating a persistent motion leading to a non-diffusive behavior of the position distribution. Nevertheless, an effective diffusive behavior emerges at times much larger than the persistence time. Here we develop a general framework for studying the long-time behavior for a class of active particle dynamics and illustrate it using the examples of run-and-tumble particle, active Ornstein–Uhlenbeck particle, active Brownian particle, and direction reversing active Brownian particle. Treating the ratio of the persistence-time to the observation time as the small parameter, we show that the position distribution generically satisfies the diffusion equation at the leading order. We further show that the sub-leading contributions, at each order, satisfies an inhomogeneous diffusion equation, where the source term depends on the previous order solutions. We explicitly obtain a few sub-leading contributions to the Gaussian position distribution. As a part of our framework, we also prescribe a way to find the position moments recursively and compute the first few explicitly for each model.
Estimation Downward Longwave Radiation Using Neural Networks in Baghdad City
Authors: Al-Sibahee Weaam M. , AL-Salihi Ali M.
Published: August 2022

The aim of the present study is to compare the accuracy and precision of the traditional method and artificial neural network (ANN) to estimate downward longwave radiation (DLR) under clear-sky conditions. DLR is useful for agriculture, global warming detection, and ecology. In order to train and estimate DLR in Baghdad, Iraq, an artificial neural network (ANN) model was developed. The activation functions (Sigmoid, Hyperbolic secant, Hyperbolic tangent), hidden layers (1, 2, 3, and 4), alteration 10000 to 50000 with interval 10000 were employed for both hidden and output layers. ANN best model was compared to eight other models based on root mean square error (RMSE) and correlation coefficient (R2). The comparative statistic for performance of the DLR model calculations during day-time and night-time have shown that the parameterization has the best results compared to the measured data. It was found that the optimum model is the (105) model where R and RMSE were 0.999 and 0.6 respectively. The results in this study indicate that the ANN can successfully be used for the estimation of DLR for Baghdad city and is more suitable than the traditional method.
Biological Activity of Ipomoea Carnea Leaves Extracts against Larval Instars of Filarial Vector Culex quinquefasciatus (Diptera: Culicidae) Mosquito
Authors: Al-Husseini Maallh T. , Merza Feryal Ameen , Al-Mousawi H. R. , Kareem Fadhil K. , Albushabaa Suhad H.
Published: August 2022

The present study was investigated the biological activity of ethanolic leaf extract of Ipomoea carnea, as well as cool and boiled aqueous extracts for investigating toxic affect against, 2nd, and 4th instar larvae of the laboratory reared mosquito species Culex
quinquefasciatus after 24, 48 and 72 h of exposure. The tested larvae of Cx. quinquefasciatus were exposed to four concentrations (5, 2, 1 and 0.5 mg/ml) of crude ethanol leaf extract for different time durations. Results were demonstrated that ethanolic leaf extract at concentrations 5 and 2 mg/ml of I. carnea affected the mortality of second and fourth instar larvae it reached 100% after 24 h from treatments. Aqueous extracts of I. carnea leaves also lead to increased mortality rates of second and fourth larvae after 72h, at 50 mg/ml for cool and boiled aqueous extracts the mortality rates were increased into 90 and 95 % respectively. The present study showed that I. carnea leaves extracts have larvicidal activity against filarial vector mosquito Cx. quinquefasciatus.
Acceleration of Bio-Ethanol Production from Waste Vegetables and Fruits by Using Zymomonas mobilis Genetically Modified
Authors: Albanna Ayman , AL-Bajjari Asmaa H.T.
Published: August 2022

The genetic modification pathways have been considered the shortest and most efficient for the production of bioethanol, in particular, that knock-in Alcohol dehydrogenase (ADH1) originally from Saccharomyces cerevisiae into the overexpression plasmid (pET28a), in order to continuous stimulate and accelerate the fermentation after inserted directly into the Zymomonas mobilis bacteria. At the same time, there are huge volumes of waste vegetables and fruit which are produced every day from restaurants and shops, and need to eliminate them with modern scientific methods, in order to the clean the environment and produced biofuel to reduce at least the use of fossil fuels. The percentage of production bioethanol was 52 % / 172 hours, which is considered a qualitative leap in the percentage of production during that period. In contrast, HPLC technique has determined the purity of bioethanol was 89.07% compared to 99% absolute ethanol which is possible to increase the purity according to the biochemical method. This study illustrated that may be commercially bioethanol produced in the future by the development of technology-based on genetic modification of bacteria.
Adding Charcoal to Diet as A means to Reduce Costs and Its Effect on Production Performance and Economic Indicators in Broilers
Authors: AL-Hamed Anwar Mohammed , Kharoufa Ali Husam
Published: August 2022

This research was done in poultry field of the Department of animals production, College of Agriculture and Forestry, University of Mosul. The duration of the research was 42 days for period from 13/11/2021 to 24 /12/2021. Unsexed day one -old broiler chicks were reared in litter at the beginning, in the second week chicks randomly distributed into four treatments, with three replicates for each treatment, They were as follows: T1: control diet (without added charcoal), T2: standard diet 3%, charcoal T3: standard diet with 5% charcoal, T4: standard diet with 7% charcoal. The results of statistical analysis shows no significant effect in live body weight, relative growth rate, feed conversion ratio, productivity, and mortality rates, with a significant superiority of the charcoal addition treatments compared to the control treatment in the rate of weight gain, the production index and the production factor. A significant increase in feed consumption was also observed for the treatment of added charcoal by 7% compared to the control treatment.
Effect of Addition Stachys Lamiaceae Water Extract on Chilling Sheep Sperms Derived from the Vas Deference’s
Authors: Al-Jabbar Ibrahim Ali Abd , Amin AL-Tawash Ali Sami , Mahdy Mohammed Rasul , Mardenli Omar , Al-Shammas Ghassan
Published: August 2022

The main objective of this study was to find out the effect of adding Stacy’s Lamiaceae plant water extract on the traits of sperms derived from the transport channels of sheep kept cold. This study was conducted using 50 ducts of adult domestic rams slaughtered at the local Al-Shula slaughterhouse. The study was carried at the College of Agriculture, University of Al-Qadisiyah, during the period from December 2020 to March 2021. This study consists of one experiment showing the effect of adding water extract of Stachys Lamiaceae on the characteristics of chilling sperms taken from the sheep Vas Deferenses. 100 VasDeferenses were divided randomly into five groups 20 Vas deferens for each group. Spermatozoa were extracted from the Vas deferens and diluted with tris extender and egg yolk, and according to the treated groups, the control group (T1) was left untreated. The second group (T2) was added 100 international units/ml of penicillin with 100 mg/ml of streptomycin. The groups (T3;1%, T4; 2% and T5; 3%, respectively) were added to the water extract of Stachys Lamiaceae and stored in the refrigerator at 5C° for one hour across one day, two days and three days. The sperms were examined (mass activity, individual motility, progressive motility, non-progressive motility, immotile sperm, dead sperm, abnormal sperm, HOST test and water test. The results indicated a significant improvement ((P<0.05) in the parameters of sperms where sperms of T5 treatment achieved the best value compared with the control group after cold storage for one, two and three days, A significant difference was noticed (P<0.05) across the treated groups with antibiotics compared with other groups. From the current study, we conclude that the addition of the water extract of the Stachys Lamiaceae led to an improvement in the environment of sperm chilling storage, which led to an improvement in the parameters of sperm fluid.