bluuebunny/crossref_metadata_2025 huggingface dataset:
The effects of vitamin B12 supplementation on metabolic profile of patients with non-alcoholic fatty liver disease: a randomized controlled trial
Authors: Talari Hamid Reza , Molaqanbari Mohamad Reza , Mokfi Milad , Taghizadeh Mohsen , Bahmani Fereshteh , Tabatabaei Seyed Mohammad Hossein , Sharifi Nasrin
Published: August 2022

The present study is the first effort to evaluate the effects of vitamin B12 supplementation on the serum level of liver enzymes, homocysteine, grade of hepatic steatosis, and metabolic profiles in patients with non-alcoholic fatty liver disease (NAFLD). Forty patients with NAFLD were enrolled in a double-blind placebo-controlled trial to receive either one oral tablet of vitamin B12 (1000 µg cyanocobalamin) or a placebo per day for 12 weeks. We investigated serum levels of homocysteine, aminotransferases, fasting blood glucose (FBG), lipids, malondialdehyde (MDA), and homeostasis model assessment of insulin resistance (HOMA-IR). The grade of liver steatosis and fibrosis was measured by real-time 2-dimensional shear wave elastography. Vitamin B12 supplementation significantly decreased serum levels of homocysteine compared to placebo (medians: − 2.1 vs. − 0.003 µmol/l; P = 0.038). Although serum alanine transaminase (ALT) in the vitamin B12 group decreased significantly, this change did not reach a significant level compared to the placebo group (medians: − 7.0 vs. 0.0 IU/l; P > 0.05). Despite the significant within-group decrease in FBG, MDA, and liver steatosis in the vitamin B12 group, between-group comparisons did not reveal any significant difference. Vitamin B12 supplementation might decrease serum levels of homocysteine in patients with NAFLD. The fasting blood glucose and serum levels of MDA were significantly improved in the trial group who received vitamin B12. However, these changes did not reach a significant level compared to the placebo group. In this respect, further studies with larger sample sizes, different doses, and types of vitamin B12 will reveal additional evidence.

Trial Registration: At http://irct.ir/ as IRCT20120718010333N5 on December 25, 2019.
Octopamine signaling via OctαR is essential for a well-orchestrated climbing performance of adult Drosophila melanogaster
Authors: El-Kholy Samar Ezzat , Afifi Basma , El-Husseiny Iman , Seif Amal
Published: August 2022

The biogenic amine octopamine (OA) orchestrates many behavioural processes in insects. OA mediates its function by binding to OA receptors belonging to the G protein-coupled receptors superfamily. Despite the potential relevance of OA, our knowledge about the role of each octopaminergic receptor and how signalling through these receptors controls locomotion still limited. In this study, RNA interference (RNAi) was used to knockdown each OA receptor type in almost all Drosophila melanogaster tissues using a tubP-GAL4 driver to investigate the loss of which receptor affects the climbing ability of adult flies. The results demonstrated that although all octopaminergic receptors are involved in normal negative geotaxis but OctαR-deficient flies had impaired climbing ability more than those deficient in other OA receptors. Mutation in OA receptors coding genes develop weak climbing behaviour. Directing knockdown of octαR either in muscular system or nervous system or when more specifically restricted to motor and gravity sensing neurons result in similar impaired climbing phenotype, indicating that within Drosophila legs, OA through OctαR orchestrated the nervous system control and muscular tissue responses. OctαR-deficient adult males showed morphometric changes in the length and width of leg parts. Leg parts morphometric changes were also observed in Drosophila mutant in OctαR. Transmission electron microscopy revealed that the leg muscles OctαR-deficient flies have severe ultrastructural changes compared to those of control flies indicating the role played by OctαR signalling in normal muscular system development. The severe impairment in the climbing performance of OctαR-deficient flies correlates well with the completely distorted leg muscle ultrastructure in these flies. Taken together, we could conclude that OA via OctαR plays an important multifactorial role in controlling locomotor activity of Drosophila.
Pedigree reconstruction and genetic analysis of major ornamental characters of ornamental crabapple (Malus spp.) based on paternity analysis
Authors: Rong Hao , Huang Bin , Han Xin , Wu Kai , Xu Meng , Zhang Wangxiang , Yang Feng , Xu Li-an
Published: August 2022

Ornamental crabapple is an important woody ornamental plant in the Northern Hemisphere. Its flowers, fruits, leaves and tree habit are all important ornamental characters. As there has been no research on the selection of superior parents and phenotypic variation, new varieties of ornamental crabapple are mainly selected from open-pollination progeny. In order to explore the transmission rule of ornamental traits between parents and offspring of crabapple, and to provide a basis for the selection of hybrid parents for directional breeding, 14 pairs of SSR markers were used in this study for paternity analysis of 384 offspring from 4 female parents crossed with 91 candidate male parents. And 273 offspring (71.1%) were matched with only the father at a 95% strict confidence level. We reconstructed 7 full-sib families (number of progeny ≥ 10) on the basis of the paternity analysis results. Genetic analysis of characters in the full-sib families revealed that green leaves and white flowers were dominant traits. All the hybrid offspring from the white flower (♀) × non-white flower (♂) cross produced white flowers, while 7.04% produced non-white flowers when both parents had white flowers. The results showed that white flowers might be a dominant qualitative trait in crabapple, while the depth of red was a quantitative trait. The genetic characteristics of green and non-green leaves and the depth of red of the peel were similar to flower color. Compared with the upright and spreading traits, the weeping trait was recessive. Some progeny showed an earlier blooming period, indicating the possibility of breeding for blooming period. Our findings are important for parent screening and improving the breeding efficiency of new varieties in ornamental crabapple hybridization.
Utilising low-cost, easy-to-use microscopy techniques for early peritonitis infection screening in peritoneal dialysis patients
Authors: Buckup Mark , Kaneda Janelle M. , Birk Alisha M. , Glockner Eleanor , Venook Ross , Jain Aditya , Sharma Shuchita , Wong Cynthia , Sutha Ken
Published: August 2022

Peritoneal dialysis (PD) patients are at high risk for peritonitis, an infection of the peritoneum that affects 13% of PD users annually. Relying on subjective peritonitis symptoms results in delayed treatment, leading to high hospitalisation costs, peritoneal scarring, and premature transition to haemodialysis. We have developed and tested a low-cost, easy-to-use technology that uses microscopy and image analysis to screen for peritonitis across the effluent drain tube. Compared to other technologies, our prototype is made from off-the-shelf, low-cost materials. It can be set up quickly and key stakeholders believe it can improve the overall PD experience. We demonstrate that our prototype classifies infection-indicating and healthy white blood cell levels in clinically collected patient effluent with 94% accuracy. Integration of our technology into PD setups as a screening tool for peritonitis would enable earlier physician notification, allowing for prompt diagnosis and treatment to prevent hospitalisations, reduce scarring, and increase PD longevity. Our findings demonstrate the versatility of microscopy and image analysis for infection screening and are a proof of principle for their future applications in health care.
Prolonged insulin-induced hypoglycaemia reduces ß-cell activity rather than number in pancreatic islets in non-diabetic rats
Authors: Jensen Vivi F. H. , Mølck Anne-Marie , Nowak Jette , Fels Johannes J. , Lykkesfeldt Jens , Bøgh Ingrid B.
Published: August 2022

Pancreatic β-cells have an extraordinary ability to adapt to acute fluctuations in glucose levels by rapid changing insulin production to meet metabolic needs. Although acute changes have been characterised, effects of prolonged metabolic stress on β-cell dynamics are still unclear. Here, the aim was to investigate pancreatic β-cell dynamics and function during and after prolonged hypoglycaemia. Hypoglycaemia was induced in male and female rats by infusion of human insulin for 8 weeks, followed by a 4-week infusion-free recovery period. Animals were euthanized after 4 or 8 weeks of infusion, and either 2 days and 4 weeks after infusion-stop. Total volumes of pancreatic islets and β-cell nuclei, islet insulin and glucagon content, and plasma c-peptide levels were quantified. Prolonged hypoglycaemia reduced c-peptide levels, islet volume and almost depleted islet insulin. Relative β-cell nuclei: total pancreas volume decreased, while being unchanged relative to islet volume. Glucagon: total pancreas volume decreased during hypoglycaemia, whereas glucagon: islet volume increased. Within two days after infusion-stop, plasma glucose and c-peptide levels normalised and all remaining parameters were fully reversed after 4 weeks. In conclusion, our findings indicate that prolonged hypoglycaemia inactivates β-cells, which can rapidly be reactivated when needed, demonstrating the high plasticity of β-cells even following prolonged suppression.
Influence of DOM and its subfractions on the mobilization of heavy metals in rhizosphere soil solution
Authors: Lian Meihua , Wang Jun , Ma Yangyang , Li Jiahui , Zeng Xiangfeng
Published: August 2022

Long-term industrial pollution, wastewater irrigation, and fertilizer application are known factors that can contribute to the contamination of heavy metals (HMs) in agricultural soil. In addition, dissolved organic matter (DOM) plays key roles in the migration and fate of HMs in soil. This study investigated the effects of amending exogenous DOM extracted from chicken manure (DOMc), humus soil (DOMs), rice husk (DOMr), and its sub-fractions on the mobilization and bio-uptake of Cd, Zn, and Pb. The results suggested that the exogenous DOM facilitate the dissolution of HMs in rhizosphere soil, and the maximum solubility of Zn, Cd, and Pb were 1264.5, 121.3, and 215.7 μg L−1, respectively. Moreover, the proportion of Zn-DOM and Cd-DOM increased as the DOM concentration increased, and the highest proportions were 97.5% and 86.9%. However, the proportion of Pb-DOM was stable at > 99% in all treatments. In addition, the proportion of hydrophilic acid (Hy) and Pb/Cd in the rhizosphere soil solution were 17.5% and 8.3%, respectively. This finding suggested that the Hy-metals complex has a vital influence on the mobilization of metals, besides its complexation with fulvic acid and humic acid. Furthermore, the elevated DOM addition contributed to an increment of HMs uptake by Sedum alfredii, in the following order, DOMc > DOMs > DOMr. This study can provide valuable insights to enhance the development of phytoremediation technologies and farmland manipulation. Since the risk that exogenous DOM would increase the uptake of HMs by crops, it is also needed to evaluate this case from an agricultural management perspective.
Influence of posterior tibial slope on sagittal knee alignment with comparing contralateral knees of anterior cruciate ligament injured patients to healthy knees
Authors: Hiranaka Yoshiaki , Muratsu Hirotsugu , Tsubosaka Masanori , Matsumoto Tomoyuki , Maruo Akihiro , Miya Hidetoshi , Kuroda Ryosuke , Matsushita Takehiko
Published: August 2022

Posterior tibial slope (PTS) has been known to contribute to anterior–posterior knee stability and play an essential biomechanical role in knee kinematics. This study aimed to investigate the effect of PTS on single-leg standing sagittal knee alignment of the intact knee. This study included 100 patients with unilateral ACL injury knee (ACL injury group, 53 patients) or with the normal knee (control group, 47 patients). The single-leg standing sagittal alignment of the unaffected knees of the ACL injury group and normal knees of the control group were assessed radiographically with the following parameters: knee extension angle (EXT), PTS, PTS to the horizontal line (PTS-H), femoral shaft anterior tilt to the vertical axis (FAT), and tibial shaft anterior tilt to the vertical axis (TAT). PTS was negatively correlated with EXT and positively correlated with TAT. EXT was significantly larger in the ACL injury group, whereas TAT was smaller in the ACL injury group. Patients with larger PTS tend to stand with a higher knee flexion angle by tilting the tibia anteriorly, possibly reducing tibial shear force. Patients with ACL injury tend to stand with larger EXT, i.e., there is less preventive alignment to minimize the tibial shear force.
Receiver aperture and multipath effects on power loss and modal crosstalk in a THz wireless link using orbital-angular-momentum multiplexing
Authors: Su Xinzhou , Zhang Runzhou , Zhao Zhe , Song Hao , Minoofar Amir , Hu Nanzhe , Zhou Huibin , Zou Kaiheng , Pang Kai , Song Haoqian , Lynn Brittany , Zach Shlomo , Tur Moshe , Molisch Andreas F. , Sasaki Hirofumi , Lee Doohwan , Willner Alan E.
Published: August 2022

The channel capacity of terahertz (THz) wireless communications can be increased by multiplexing multiple orthogonal data-carrying orbital-angular-momentum (OAM) beams. In THz links using OAM multiplexing (e.g., Laguerre-Gaussian $${\mathrm{LG}}_{ \ell,p}$$

LG

ℓ
,
p

beams with p = 0), the system performance might degrade due to limited receiver aperture size and multipath effects. A limited-size aperture can truncate the received beam profile along the radial direction. In addition, due to beam divergence, part of the beam might interact with reflectors in the environment, causing the signal to reflect and interfere at the receiver with the directly propagating part of the beam; this is known as the multipath effect. In this paper, we simulate and analyze the impact of both effects on the equality of the THz OAM link by considering a full two-dimensional (2-D) LG modal set. The simulation results show (i) a limited-size receiver aperture can induce power loss and modal power coupling mainly to LG modes with the same ℓ but p > 0 for directly propagated OAM beams; (ii) the multipath effect can induce modal power coupling across multiple 2-D LG modes, which leads to inter-channel coupling among the different channels in an OAM multiplexed link; (iii) the interference between the reflected and direct beams can induce intra-channel coupling between the received signals from the reflected and direct beams; and (iv) beams with a higher OAM order (e.g., from ± 1 to ± 5) or a lower carrier frequency (e.g., from 0.1 to 1 THz) experience larger intra- and inter-channel coupling. The intra- and inter-channel coupling in an OAM-multiplexed THz link can degrade the signal-to-noise ratio (SNR) and induce SNR penalty when compared to a single-channel system.
Automated diagnosis of optical coherence tomography imaging on plaque vulnerability and its relation to clinical outcomes in coronary artery disease
Authors: Niioka Hirohiko , Kume Teruyoshi , Kubo Takashi , Soeda Tsunenari , Watanabe Makoto , Yamada Ryotaro , Sakata Yasushi , Miyamoto Yoshihiro , Wang Bowen , Nagahara Hajime , Miyake Jun , Akasaka Takashi , Saito Yoshihiko , Uemura Shiro
Published: August 2022

This study sought to develop a deep learning-based diagnostic algorithm for plaque vulnerability by analyzing intravascular optical coherence tomography (OCT) images and to investigate the relation between AI-plaque vulnerability and clinical outcomes in patients with coronary artery disease (CAD). A total of 1791 study patients who underwent OCT examinations were recruited from a multicenter clinical database, and the OCT images were first labeled as either normal, a stable plaque, or a vulnerable plaque by expert cardiologists. A DenseNet-121-based deep learning algorithm for plaque characterization was developed by training with 44,947 prelabeled OCT images, and demonstrated excellent differentiation among normal, stable plaques, and vulnerable plaques. Patients who were diagnosed with vulnerable plaques by the algorithm had a significantly higher rate of both events from the OCT-observed segments and clinical events than the patients with normal and stable plaque (log-rank p < 0.001). On the multivariate logistic regression analyses, the OCT diagnosis of a vulnerable plaque by the algorithm was independently associated with both types of events (p = 0.047 and p < 0.001, respectively). The AI analysis of intracoronary OCT imaging can assist cardiologists in diagnosing plaque vulnerability and identifying CAD patients with a high probability of occurrence of future clinical events.
The evaluation of parameter effects on cefoperazone treatability with new generation anodes
Authors: Kurt Ayşe , Yonar Taner
Published: August 2022

In this study it was aimed to investigate the treatability of cefoperazone with new generation Sb-doped SnO2-Ni anodes. For this purpose, it was studied with Sn/Sb/Ni: 500/8/1 anodes for the oxidation of aqueous solution containing cefoperazone antibiotic by addition of different types of electrolyte. Potassium chloride was found as the best electrolyte type affecting the electrochemical reactions positively even at lower concentrations (750 mg/L−1). At pH 8 the best results were obtained, which is the neutral pH value of the aqueous solution. 50 mA/cm2was found as the best value for current density parameter, providing full mineralization just after 60 min of reaction. The removal efficiencies increased generally with the increase of current density, because active oxidants occur increasingly at higher current values. According to the results of the study it was seen that, electrochemical oxidation processes with Sn/Sb/Ni–Ti anodes could be carried out efficiently without need adding extra electrolyte (salt) and pH adjustment step for real wastewaters containing antibiotics. Thus, it was found an easy and economic way to perform electrochemical oxidation with Sn/Sb/Ni–Ti anodes for the wastewaters containing cefoperazone antibiotics.
Comparison of various indices for predicting sarcopenia and its components in patients receiving peritoneal dialysis
Authors: Do Jun Young , Kang Seok Hui
Published: August 2022

This study aimed to evaluate and compare the usefulness of four indices—arm circumference, thigh circumference, mid-arm muscle circumference (MAMC), and thigh muscle circumference (TMC)—with that of other classical indicators of body composition in the prediction of sarcopenia and two sarcopenia-related components in patients receiving peritoneal dialysis (PD) grouped by sex. The data of all patients receiving PD who visited a tertiary medical center were collected (n = 214); of them 199 patients undergoing PD were included in the final analyses. Data on baseline characteristics and measurements, including circumferences of appendicular sites, handgrip strength (HGS), and appendicular lean mass (ALM) index, were obtained during a routine peritoneal membrane equilibration test. Body composition was evaluated using dual-energy X-ray absorptiometry. The ALM index (kg/m2) was defined as the sum of lean mass in the upper and lower extremities divided by height squared. Sarcopenia was defined as low HGS and low muscle mass based on the cut-off values in the Asian Working Group for Sarcopenia guideline. The circumferences of the lower extremities showed the greatest association with the ALM index in both sexes. Prediction of HGS was better with the MAMC than with the other indices in the male patients, whereas none of the indices were associated with HGS in the female patients. Moreover, the MAMC in the male patients and TMC in the female patients were the strongest predictors of sarcopenia among the six anthropometric indices. This study showed that the MAMC in male PD patients and TMC in female PD patients might be the best predictors of sarcopenia. However, the TMC was associated with sarcopenia regardless of HGS in the female PD patients. These findings suggest that, in PD patients, different indices should be considered in predicting sarcopenia or its components based on the sex.
Single-cell atlas of diverse immune populations in the advanced biliary tract cancer microenvironment
Authors: Shi Xuebing , Li Zhixuan , Yao Renqi , Cheng Qingbao , Li Wei , Wu Rui , Xie Zhihua , Zhu Yanjing , Qiu Xinyao , Yang Shuai , Zhou Tao , Hu Ji , Zhang Yangqianwen , Wu Tong , Zhao Yan , Zhang Yani , Wu Jianmin , Wang Hongyang , Jiang Xiaoqing , Chen Lei
Published: August 2022

Immunotherapies have been explored in treating solid tumors, albeit with disparate clinical effects in distinct cancer types. Systematic interrogation of immune cells in the tumor microenvironment (TME) is vital to the prediction of immunotherapy response and the development of innovative immunotherapeutics. To comprehensively characterize the immune microenvironment in advanced biliary tract cancer (BTC), we utilized single-cell RNA sequencing in unselected viable cells from 16 matched samples, and identified nineteen cell subsets from a total of 45,851 cells, in which exhausted CD8+T cells, macrophages, and dendritic cells (DCs) in BTC were shown to augment and communicate within the TME. Transcriptional profiles coupled with T cell receptor (TCR) sequences revealed that exhausted CD8+T cells retained clonal expansion and high proliferation in the TME, and some of them highly expressed the endoplasmic reticulum stress (ER) response gene,XBP1, indicating the role of ER stress in remodeling TME. Functional assays demonstrated that XBP1 and common immune checkpoints (PD1, TIGIT) were significantly upregulated in CD8+T cells cocultured within the TME of BTC cells (GBC-SD, HCCC-9810). When treating the coculture groups with the specific inhibitor of IRE1α-XBP1 (4μ8C), the downregulation of TIGIT was observed in the treatment group. Collectively, comprehensive transcriptome profiling provides deep insights into the immune atlas in advanced BTC, which might be instrumental in exploring innovative immunotherapy strategies.
Historical patterns and sustainability implications of worldwide bicycle ownership and use
Authors: Chen Wu , Carstensen Trine Agervig , Wang Ranran , Derrible Sybil , Rueda David Rojas , Nieuwenhuijsen Mark J. , Liu Gang
Published: August 2022

Bicycles are widely recognized as an effective solution for reducing short-distance trip-related climate impacts and addressing sedentary lifestyle-caused chronic diseases. Yet, the historical patterns of global bicycle production, trade, stock, and use remain poorly characterized, preventing thorough investigation of its role in sustainable road transport transition. Here, based on a dynamic model and various data sources, we have compiled, to our knowledge, the first global dataset for bicycle ownership and use by country from 1962 to 2015. Our comparison between the historical development of per-capita bicycle ownership and car ownership reveals five varying types in an S-curve among different countries. High bicycle ownership does not necessarily lead to high bicycle use, which is instead still marginal in daily trips worldwide (<5% for most countries). A worldwide pro-bicycle policy and infrastructure development enabled modal shift like the Netherlands and Denmark can lead to significant untapped climate and health benefits.
Thermal desorption bridged the gap between dielectric barrier discharge ionization and dried plasma spot samples for sensitive and rapid detection of fentanyl analogs in mass spectrometry
Authors: Li Dongmei , Li Zehua , Xu Bin , Chen Jia , Xue Jinjuan , Hu Shundi , Wen Luhong , Guo Lei , Xie Jianwei , Jiang Guibin
Published: August 2022

Guided by finite element simulations and 3D-printing, we constructed a semi-covered flat-TD surface for sufficient thermal desorption and ionization of fentanyl analogs from dried plasma/blood spot samples.
Slab waveguide-based particle plasmon resonance optofluidic biosensor for rapid and label-free detection
Authors: Barshilia Devesh , Komaram Akhil Chandrakanth , Chen Pin-Chuan , Chau Lai-Kwan , Chang Guo-En
Published: August 2022

We demonstrate a cost-effective, rapid, and sensitive slab waveguide-based particle plasmon resonance biosensor with enhanced optical near field through the localized surface plasmon resonance effect for practical clinical applications.
A hydrogen-driven biocatalytic approach to recycling synthetic analogues of NAD(P)H
Authors: Reeve Holly A. , Nicholson Jake , Altaf Farieha , Lonsdale Thomas H. , Preissler Janina , Lauterbach Lars , Lenz Oliver , Leimkühler Silke , Hollmann Frank , Paul Caroline E. , Vincent Kylie A.
Published: August 2022

Soluble hydrogenase enables atom efficient, H2-driven, recycling of synthetic nicotinamide cofactors.
Genetically encoded fluorescent unnatural amino acids and FRET probes for detecting deubiquitinase activities
Authors: Li Manjia , Wang Feifei , Yan Long , Lu Minghao , Zhang Yuqing , Peng Tao
Published: August 2022

7-Aminocoumarin-derived fluorescent unnatural amino acids are site-specifically incorporated into proteins and utilized to develop fully genetically encoded FRET probes for deubiquitinases.
Structures and localized vibrational states of defects in graphite by tight-binding calculations
Authors: Cheng Rong , Lu Wen-Cai , Ho K. M. , Wang C. Z.
Published: August 2022

Three-center tight-binding potential for carbon enables efficient and accurate large-scale calculation and molecular dynamics simulation of defect structures and defect-induced localized vibrational modes in graphite.
Knotting matters: orderly molecular entanglements
Authors: Ashbridge Zoe , Fielden Stephen D. P. , Leigh David A. , Pirvu Lucian , Schaufelberger Fredrik , Zhang Liang
Published: August 2022

We review recent progress in molecular knotting, the chemistry of orderly molecular entanglements. As complex nanotopologies become increasingly accessible they may play significant roles in molecular design.
γ-FeO(OH) with multiple surface terminations: Intrinsically active for the electrocatalytic oxygen evolution reaction
Authors: Mallick Laxmikanta , Rajput Anubha , Adak Mrinal Kanti , Kundu Avinava , Choudhary Pratigya , Chakraborty Biswarup
Published: August 2022

A small alteration in reaction strategy leads to isolation of different phase and crystallinity of the iron-oxyhydroxides during the oxygen evolution reaction in alkaline medium. Polycrystalline Lepidocrocite possessing multiple surface terminals is the most active catalyst.
Spatial niche construction of a consortium-based consolidated bioprocessing system
Authors: Gao Hao , Li Minhui , Yang Lu , Jiang Yujia , Jiang Wankui , Yu Ziyi , Zhang Wenming , Xin Fengxue , Jiang Min
Published: August 2022

A bioreactor with custom-designed living materials and a 3D printed device for the CBP system was developed, providing defined spatial niches fitting specific oxygen needs for the biochemical production.
Boosting charge migration in V2O5 nanorods by niobium doping for enhanced photocatalytic activity
Authors: Basu Soumya Shankar , Donode Shweta Kishor , Sengupta Sonali , Basu Jayanta Kumar
Published: August 2022

Niobium dopants have improved the structural and optoelectronic properties of V2O5 nanorods, resulting in enhanced charge kinetics for photocatalytic and photoelectrochemical activity.
Improving thermoelectric performance by constructing a SnTe/ZnO core–shell structure
Authors: Li Song , Zhang Jingwen , Liu Dawei , Wang Yan , Zhang Jiuxing
Published: August 2022

Energy filtering effect introduced by the SnTe/ZnO core–shell structure in SnTe-based TE materials increases the ZT by approximately 50%.
Palladium-catalyzed nucleomethylation of alkynes for synthesis of methylated heteroaromatic compounds
Authors: Yang Xi , Wang Gang , Ye Zhi-Shi
Published: August 2022

A novel palladium-catalyzed nucleomethylation of alkynes is developed, affording 3-methylindoles, 3-methylbenzofurans and 4-methylisoquinolines in moderate to excellent yields.
Cellular orientational fluctuations, rotational diffusion and nematic order under periodic driving
Authors: Moriel Avraham , Livne Ariel , Bouchbinder Eran
Published: August 2022

Cells response to periodic driving forces in noisy environments is crucial for their function. A theory that includes active fluctuations quantitatively explains the resulting cellular probability distributions in response to such driving forces.
Response of vesicle shapes to dense inner active matter
Authors: Park Myeonggon , Lee Kisung , Granick Steve
Published: August 2022

Active membrane fluctuations of giant unilamellar vesicles, driven by encapsulated dense bacteria, is determined predominantly by bacterial collective behaviour.
Oxygen defect engineering endows Co3O4 nanosheets with advanced aluminum ion storage
Authors: Zheng Jiening , Xu Tian , Xia Guanglin , Yu Xuebin
Published: August 2022

Oxygen vacancies were introduced into Co3O4 to enhance the rate capability and cycling stability of aluminum ion batteries.
A comprehensive analytical description of the asymmetric active snubber
Authors: Schlüter Michael , Pfost Martin
Published: August 2022

Power modules for several hundred amperes suffer from a high stray inductance compared to discrete setups at similar current density. The use of silicon carbide in such modules is beneficial but due to the high stray inductance, the switching speed must be reduced to keep the voltage overshoot below breakdown voltage. As a result, the semiconductor material cannot be fully utilised. To improve the utilisation in terms of power output, by strong over‐voltage reduction, reduced ringing, and highest switching speeds an asymmetric active snubber was introduced. This work targets an improved understanding of the active snubber by deriving analytical models to describe the behaviour during turn‐on and turn‐off and elaborate optimisation opportunities. The models are compared to measurements for validation and an improved loss estimation is derived as well as a prediction of the snubber voltage. Different modes of operation are investigated and compared to a similar DC‐snubber setup. Finally, the model is used to pre‐calculate the timing for optimal operation.
A first search of transients in the Galactic center from 230 GHz ALMA observations
Authors: Mus A. , Martí-Vidal I. , Wielgus M. , Stroud G.
Published: August 2022

The Galactic center (GC) presents one of the highest stellar densities in our Galaxy, making its surroundings an environment potentially rich in radio transients, such as pulsars and different kinds of flaring activity. In this paper, we present the first study of transient activity in the region of the GC based on Atacama Large Millimeter/submillimeter (mm/submm) Array (ALMA) continuum observations at 230 GHz. This search is based on a new self-calibration algorithm, especially designed for variability detection in the GC field. Using this method, we have performed a search of radio transients in the effective field of view of ∼30 arcsec of the GC central supermassive black hole Sagittarius A* (Sgr A∗) using ALMA 230 GHz observations taken during the 2017 Event Horizon Telescope (EHT) campaign, which span several observing hours (5–10) on 2017 April 6, 7, and 11. This calibration method allows one to disentangle the variability of unresolved Sgr A∗ from any potential transient emission in the wider field of view and residual effects of the imperfect data calibration. Hence, a robust statistical criterion to identify real transients can be established: the event should survive at least three times the correlation time and it must have a peak excursion of at least seven times the instantaneous root-mean-square between consecutive images. Our algorithms are successfully tested against realistic synthetic simulations of transient sources in the GC field. Having checked the validity of the statistical criterion, we provide upper limits for transient activity in the effective field of view of the GC at 230 GHz.
The coexistence of the streaming instability and the vertical shear instability in protoplanetary disks
Authors: Schäfer Urs , Johansen Anders
Published: August 2022

The streaming instability is a promising mechanism to induce the formation of planetesimals. Nonetheless, this process has been found in previous studies to require either a dust-to-gas surface density ratio or a dust size that is enhanced compared to observed values. Employing two-dimensional global simulations of protoplanetary disks, we show that the vertical shear instability and the streaming instability in concert can cause dust concentration that is sufficient for planetesimal formation for lower surface density ratios and smaller dust sizes than the streaming instability in isolation, and in particular under conditions that are consistent with observational constraints. This is because dust overdensities forming in pressure bumps induced by the vertical shear instability act as seeds for the streaming instability and are enhanced by it. While our two-dimensional model does not include self-gravity, we find that strong dust clumping and the formation (and dissolution) of gravitationally unstable overdensities can be robustly inferred from the evolution of the maximum or the mean dust-to-gas volume density ratio. The vertical shear instability puffs up the dust layer to an average mid-plane dust-to-gas density ratio that is significantly below unity. We therefore find that reaching a mid-plane density ratio of one is not necessary to trigger planetesimal formation via the streaming instability when it acts in unison with the vertical shear instability.
Fluid simulation of dust-acoustic solitary waves in the presence of suprathermal particles: Application to the magnetosphere of Saturn
Authors: Singh Kuldeep , Kakad Amar , Kakad Bharati , Kourakis Ioannis
Published: August 2022

The observation of dust in the rings of Saturn by instruments on board the Voyager 1, Voyager 2, and Cassini missions triggered our interest in exploring the evolution of electrostatic dust acoustic waves (DAWs) in the Saturnian magnetospheric dusty plasma. The salient features of dust-acoustic electrostatic solitary waves have been examined by means of numerical simulations that adopted a fluid algorithm. We considered highly energetic non-Maxwellian ion and electron populations, in combination with inertial dust. The ions and electrons were modeled by kappa distributions to account for the long-tailed particle distribution featuring a strong suprathermal component. At equilibrium, the initial density perturbation in the dust density was used to trigger the evolution of DASWs propagating in non-Maxwellian dusty plasma. Our main focus is to determine the comprehensive role of the dust concentration and the suprathermal index (kappa) of the ion and electron populations in the generation and evolution of DASWs. These simulation results are thought to be relevant for (and applicable in) existing experimental data in space, especially in the magnetosphere of Saturn, but also in other planetary plasma environments that are presumably characterized by the presence of charged dust.
De la métrologie à la métallurgie de précision Charles-Édouard Guillaume, prix Nobel de physique 1920
Authors: Lebrun Philippe , Schaff Hubert
Published: August 2022

Dans un précédent numéro de Reflets de la physique, un article de J.E. Wesfreid (n°65, pp. 30-33) décrivait les recherches aérodynamiques de Gustave Eiffel. Suite à cet article, avec Hubert Schaaf (ancien président de la SF2M), j’ai interrogé les lecteurs sur le nom du lauréat Nobel qui a effectué la mesure de la hauteur de la Tour. La riche et unique réponse à la question que j’avais posée a été donnée par Philippe Lebrun, physicien des accélérateurs du CERN.

Ces deux chercheurs (qui ne se connaissaient pas auparavant) nous présentent, dans une rubrique d’histoire des sciences, l’ensemble des activités de recherche appliquée du métallurgiste Charles-Édouard Guillaume (prix Nobel de physique 1920), insuffisamment reconnu aujourd’hui. Le centième anniversaire de la mort d’Eiffel en 2023 fournira d’autres occasions d’aborder la métallurgie.

Étienne Guyon
COVID-19 Vaccination May Provoke Intracranial Hypertension
Authors: Melendez-Zaidi Alexandria E. , Foroozan Rod , Orman Gunes , Abid Farida
Published: August 2022

In parallel to the spread of the novel severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2), there has been the growing recognition that active SARS-CoV-2 infection has the potential to effect both the peripheral and central nervous systems. When it comes to the SARS-CoV-2 vaccine, however, reporting has been more uncertain. As the vaccination rate has risen, we have seen a rise in rare neurological complications thought to be associated with the vaccination including acute transverse myelitis, Guillain–Barre syndrome, optic neuritis, and Tolosa–Hunt syndrome. The Centers for Disease Control and Prevention (CDC) estimates 98 confirmed cases of Guillain–Barre syndrome out of 12.6 million doses. Given the initial age limits of vaccination eligibility, most reports have been limited to the adult population. Here, we report a case of intracranial hypertension (IH), evolving to fulminant IH in a healthy female after receiving the SARS-CoV-2 vaccine. While elevated intracranial pressure has been reported in the context of active SARS-CoV-2 infections and postinfection multisystem inflammatory syndrome (MIS-C), this is the first reported case of pediatric IH after vaccination alone.
A versatile microtomography system to study in situ the failure and fragmentation in geomaterials
Authors: Francois N. , Cruikshank R. , Herring A. , Kingston A. , Webster S. , Knackstedt M. , Saadatfar M.
Published: August 2022

This article describes a microtomography experimental platform enabling in situ micro-mechanical study of failure and fragmentation in geomaterials. The system is based on an original high-pressure triaxial flow cell, which is fully integrated into a custom built microtomography scanner equipped with a laboratory x-ray source. The design of the high-precision mechanical apparatus was informed by the concurrent development of advanced tomographic reconstruction methods based on helical scanning and of algorithms correcting for hardware inaccuracies. This experimental system produces very high-quality 3D images of microstructural changes occurring in rocks undergoing mechanical failure and substantial fragmentation. We present the results of two experiments as case studies to demonstrate the capabilities and versatility of this instrumental platform. These experiments tackle various questions related to the onset of rock failure, the hydromechanical coupling and relaxation mechanisms in fractured rocks, or the fragmentation process in geomaterials such as copper ores.
Discharge modes and liquid interactions for plasma-bubble discharges
Authors: Lu Xu , Wang Sen , Zhou Renwu , Fang Zhi , Cullen P. J.
Published: August 2022

Plasma bubbles are regarded as a promising means of interacting plasma discharges and liquids due to their high efficiency in the generation of reactive species. The discharge mode and characteristics are significant factors that should be considered. In this study, the plasmas are initially generated in the gas phase and then driven by the gas flow to diffuse into the solution through the two holes at the lower part of the quartz tube to form plasma bubbles. The discharge modes, characteristics, and plasma–liquid interactions in two different configurations, i.e., bare electrode and dielectric-coated electrode, are investigated. It is found that the discharge mode induced for the two structures is different, with a hybrid-mode operating in the bare electrode design and a filamentary mode operating in the dielectric design. When the applied voltage is increased, a filamentary-to-spark transition occurs in the bare structure, while the discharge remains relatively stable in the dielectric design. Direct and intense contact between the discharge and the solution in the bare structure greatly promotes the physio-chemical reactions and results in obvious changes in H2O2 concentration, solution pH, conductivity, and temperature. This study provides insights into hybrid gas–liquid discharges and reactor design for plasma bubble generation.
Machine learning on the ignition threshold for inertial confinement fusion
Authors: Yang Chen , Zhang Cunbo , Gao Congzhang , Xu Xuefeng , Yu Chengxin , Wang Shuaichuang , Fan Zhengfeng , Liu Jie
Published: August 2022

In inertial confinement fusion, the ignition threshold factor (ITF), defined as the ratio of the available shell kinetic energy to the minimum ignition energy, is an important metric for quantifying how far an implosion is from its performance cliff. Traditional ITF research is based on analytical theories with explicit scaling laws and parameters obtained by numerically fitting simulation data. This present study uses machine learning (ML) methods to train implicit but more reliable ITF expressions. One-dimensional numerical simulations are used to develop a dataset with 20 000 targets, in which alpha particle heating magnifies the fusion yield by a factor of 6.5. These targets are defined as marginal ignition targets whose ITF equals unity. ML models such as neural networks, support vector machines, and Gaussian processes are trained to connect the minimum ignition velocity vigt with other implosion parameters, yielding an ML-based ITF of (vimp/vigt)7.5, where vimp represents the implosion velocity. Then, these ML models are used to obtain curves of the ignition probability vs the ITF and improved ignition cliffs that show considerably better accuracy than traditional scaling laws, which are observed. The results demonstrate that ML methods have promising application prospects for quantifying ignition margins and can be useful in optimizing ignition target designs and practical implosion experiments.
Terahertz radiation enhancement in gallium arsenide nano-hole array under low power optical pump
Authors: Wang Kemeng , Gu Yangfan , Lu Yongchang , Gu Jianqiang , Zhang Weili
Published: August 2022

Though accelerating photocarriers by the semiconductor surface electric field is the simplest way to generate broadband terahertz pulses, the weak THz power under low optical pump hinders its application in these compact systems. Here, we report a ⟨100⟩ semi-insulating gallium arsenide nano-hole array under above-the-bandgap excitation, which boosts terahertz emission power up to 5.75 folds of bare gallium arsenide with a 32 mW pump. The nano-structured array lifts the absorption of the optical pump and localizes the photocarriers near the surface of gallium arsenide, benefiting the transient photocurrents and thus the THz power. Interestingly, the enhancement is poorly related to the terahertz frequency, and the power difference of the emitted THz wave under the TE and TM pumps is greatly smoothed. In addition, the THz emission enhancement of the nanoscale hole arrays favors a low-power pump. The demonstration shown here provides a potential route for advancing the weak THz power of surface emission, which will promote the application of the surface emitting THz source in the practical THz systems employing compact femtosecond lasers.
The influence of A-site dipole moment on iodine migration in perovskite films revealed by transient ion drift
Authors: Li Biao , Xu Xuehui , Yao Yuxin , Hang Pengjie , Kan Chenxia , Wang Ying , Zhang Yiqiang , Yang Yang (Michael) , Yang Deren , Yu Xuegong
Published: August 2022

Ion migration is regarded as the chief culprit for the long-term instability in perovskite solar cells (PSCs), and iodine ions are the most subjects to migration in PSCs. Strategies, such as grain size engineering, chemical bonding engineering, steric impediment effect, and interface passivation, are employed to suppress the iodine migration but unfortunately are unable to completely eliminate it. Here, the influence of the dipole moment of A-site ions on iodine migration has been comprehensively investigated for perovskite films based on different A-site cations via a transient ion drift (TID) method. TID results demonstrate that the decrease in the strength of the dipole moment of A-site ions can lead to a decrease in the activation energy (EA) of iodine ions. Therefore, this work suggests that increasing the strength of dipole moment of A-site ions can be utilized as an effective strategy for suppressing iodine migration in perovskite films providing critical insight for enhancing the long-term stability for PSCs.
Characterization parameters for antennas generating orbital angular momentum waves
Authors: Wang Zhixia , Zheng Shilie , Zheng Jiayu , Wu Han , Wang Zian , Hui Xiaonan , Yu Xianbin , Zhang Xianmin
Published: August 2022

As one of the pivotal candidate technologies of 6G, orbital angular momentum (OAM) carrying radio waves have attracted much attention in wireless communication and sensing technology fields owing to the particular twisted phase fronts. Various kinds of antennas have been proposed to generate this kind of wave; however, the antenna performance has not been well analyzed in terms of the OAM carrying wave’s characteristics. In this paper, some dedicated characterization parameters termed as conjugated receiving pattern, purity related bandwidth, and mode phase linearity based on well-known properties of OAM carrying electromagnetic waves are proposed for the first time. These parameters can be used to characterize the performance of OAM antennas. As an example, the performance of a fabricated helical OAM antenna with a wide bandwidth is characterized by the proposed parameters, which proves the reasonableness and necessity of the proposed characterization parameters.
Compact pulse generator with sub-nanosecond rise time based on inductance of order of several nH
Authors: Li Junna , Wang Yongliang , He Shi , Chen Xuliang , Qiu Aici
Published: August 2022

Pulse generators with a sub-nanosecond rise time are typically used to calibrate measurement probes in electromagnetic pulses. However, the technological dilemma between high voltage and low inductance has not been adequately addressed in this context. In this paper, the authors investigate the effects of the circuit and structural parameters on the generator. To reduce the rise time of the output voltage of the generator to a few hundred picoseconds, the inductance of its structure and the spark gap needs to be strictly controlled. We use SF6 at 1 MPa as an insulating gas for the spark gap to reduce the inductance of the capacitor and the switch to the order of several nH. The results of theoretical calculations and simulations were used to design and test two generators that used a coaxial ceramic capacitor and three plate ceramic capacitors, respectively. The experimental results showed that a double-exponential pulse voltage with a sub-nanosecond rise time could be obtained in a 50 Ω transmission line in both generators. The generator with the coaxial ceramic capacitor had better characteristics than the one that used three plate ceramic capacitors with a rise time of 630–860 ps when the peak output voltage was in the range of 5–30 kV.