bluuebunny/crossref_metadata_2025 huggingface dataset:
Immune escape mechanism of B-cell malignancies on Anti-CD19 Chimeric Antigen Receptor T-cell treatment and solution
Authors: Qian Jin
Published: June 2021

Relapse or refractory B-cell malignancies have been reported in multiple clinical trials after treatment of Anti-CD19 Chimeric Antigen Receptor (CAR) T-cells. Many clinical studies have demonstrated the potential immune escape mechanism for B-cell malignancies like genetic mutation, transcriptional deregulation, lineage switch, loss of CAR T-cells, and trogocytosis. The study of these mechanisms can provide us insights in designs of future immunotherapies regarding both B-cell malignancies and even other solid tumors. The potential solution for the immune escape mechanisms regarding CAR T-cell treatment is engineering multispecific CARs. In this article, I review most of the upto- date immune escape mechanism studies and some multispecific CAR T-cell treatment clinical studies and trials that may prevent the escape route and have to potential to cure B-cell malignancies.
An Overview of Bioactive Natural Products-Based Nano-Drug Delivery Systems in Antitumor Chemotherapy
Authors: Niu Yihao
Published: June 2021

Many bioactive natural products are derived from traditional Chinese medicine. Some of them showed good treatment potential in tumor chemotherapy. However, limited by the poorly solubility and non-selective toxicity of most of bioactive natural products, their antitumor efficacy could not be further applied in clinicals. Nano-drug delivery systems provided good platforms for bioactive natural products in antitumor treatment, and many tumor microenvironment-responsive nano-delivery carriers facilitated them to achieve more accurate tumor targeting and less toxicity, and finally improved antitumor ability of bioactive natural products.
Evaluation of the Effect of Nursing Intervention on the Curative Effect and Living Ability of Elderly Patients with Myocardial Infarction
Authors: Gao Junying
Published: June 2021

This article is to explore the effect of applying nursing intervention methods on the life ability of elderly patients with myocardial infarction. The method of this reserch is to take patients in our hospital as an example to carry out research work. The study selected patients who were treated in our hospital from December 2019 to December 2020 as an example. The researchers selected all elderly patients with myocardial infarction, and the number of patients was selected as 100 cases. The different nursing methods of patients were divided into two groups --- the conventional nursing methods and comprehensive nursing methods were applied respectively, named the control group and the research group, and the nursing effects of the two groups of patients were compared and analyzed. The effective rates of the two groups of patients were 98.00% and 82.00% respectively. At admission, the patients’ BNP, living ability and psychological scores were significantly higher than those of the control group. There was a big difference in data between the groups, P>0.05. After nursing intervention, the patients in the research group had better scores compared with the control group, P<0.05, which was statistically significant, and the research group had better nursing effects. The application of comprehensive nursing methods in elderly patients with myocardial infarction has a significant clinical effect, which can improve the living ability of the patients and is of positive significance for the recovery of the patients.
Non-pharmaceutical Therapy for Depression
Authors: Xu Ruotong
Published: June 2021

At present, the non-drug treatment of depression has developed rapidly. Diverse methods which have quick effects, less injury, good adherence and other advantages are becoming available for all kinds of people. However, clinical workers need to choose treatment for patients according to their individual characteristics with an accurate and flexible use of non-drug therapy approach, in order to quickly and effectively reduce the patients' pain, allow their souls to return home and return to society. Nevertheless, it still needs to be further explored and studied. This article discusses the treatment of non-medicated depression by looking up documents online about non-pharmaceutical treatment of depression to help people find the best way to get rid of the disease without relying partly on drugs and to provide references for medical treatment.
A Brief Talk of the Disinfection Process for Reclaimed Water
Authors: Feng Zhiqiang , Xue Rongrong , Ge Liyan
Published: June 2021

In recent years, with the reclaimed water being more and more widely used, people begin to pay more and more attention to the security of it. Because the reclaimed water comes from the sewage, which has been deeply treated, its quality is quite complex and it may contain many bacteria, viruses and poisonous that are harm to people. When it’s reused, it is inevitable that the reclaimed water may come into contact with people’s body, which has exposure risk. In order to reduce the risk of exposure, ensure the security of the quality of the reclaimed water, the disinfection becomes the most critical factors in dealing with the reclaimed water in the process. In the paper, the current disinfection techniques were discussed and compared in the aspects of technical features, the effects of disinfection and economy. And a brief summary of the new disinfection technology that was widely studied was made.
Improvement of thermal stability of Ta-N film in Cu metallization by a Zr-Si interlayer
Authors: Zhai Yannan , Wang Zhaoxin , Zhang Hui , Gao Ling , Ding Changhong
Published: June 2021

Ta-N (10 nm)/Zr (20 nm) film was grown on n-type (100) silicon wafer at various substrate temperatures in a rf magnetron sputtering system, followed by in situ deposition of Cu. The Cu/Ta-N/Zr/Si samples were subjected to thermal annealing up to 800 ℃ under the protection of pure nitrogen gas. In order to investigate the effect of insertion of a thin Zr layer under Ta-N film on Ta-N diffusion barrier performance in Cu metallization, Cu/Ta-N/Zr/Si contact system was characterized by X-ray diffraction (XRD), four-point probe (FPP) measurement, scanning electron microscopy (SEM), and Auger electron spectroscopy (AES) depth profile. The results reveal that the microstructure of Ta-N films deposited on Zr is amorphous at different substrate temperatures. The barrier breakdown temperature of Ta-N/Zr film is about 100°C higher than that of Ta-N. It can effectively prevent the diffusion of Cu after annealed at 800°C. The improvement of diffusion barrier performance may be due to the production of Zr-Si layer with low contact resistivity after annealed at 800°C.
Systematic Longitudinal Evaluating on boosting preschool children’s food literacy
Authors: Tian Guo , weiwei Liu
Published: June 2021

To evaluate different methods in lifting food literacy which are applied to preschool children. Most articles are based on cross-sectional studies, an observational longitudinal design is seldom used, making it difficult to identify the true effectiveness of the methods. Thus, this article use a longitudinal method, including several online database. A systematic article based on longitudinal researches, by searching data in four electronic databases, Web of Science, PubMed, Elsevier (Science Direct) and Google Scholar, setting eligibility criteria, data selection, extracting data, data synthesis and quality assessment. Study identifies 771 original data, and after the de-duplication and eligibility selection, 9 studies are included in the article. Despite the small amount of literature applied, evidences are quiet useful. In comparison of caregiver-based intervention and classroom-based intervention, the later shows more effectiveness in short-term awareness training. Also, great potential has been found in technology-based intervention. The authors recommend future studies to focus on longitudinal research, so as to assess the potential of early childhood food literacy intervention, the mechanism and methods of these studies, the duration and effectiveness in different followup time etc.
Postoperatives Dumping-Syndrom mit nachhaltiger Störung der Glukosehomöostase – Linderung durch Flash-Glukosemessung und individuelle Indikationsstellung für Glucagon-like-Peptide-1(GLP-1)-Rezeptoragonisten
Authors: Leuz Jule , Brecht Laura , Nattermann Jacob , Glowka Tim , Ballmann Clemens , Dahlem Marcus , Schmitz Volker
Published: June 2021

Das Auftreten von Dumping-Syndromen nach Magenresektion/Magenteilresektion ist keine Seltenheit. Die Beschwerden sind vielfältig mit vasomotorischen Reaktionen mit Kollapsneigung und Verdauungsstörungen (Frühdumping) und Blutzuckerentgleisungen aufgrund zu schneller Aufnahme von Glukose im Dünndarm (Spätdumping).

Etablierte Therapieansätze führen nicht immer zu den gewünschten Therapieerfolgen. Wie auch im hier vorliegenden Fallbeispiel werden dann individuelle Therapiekonzepte nötig, um die Lebensqualität der Patienten wiederherzustellen.
An Ayurveda Gargle Regimen in Management of Radiotherapy-induced Oral Mucositis
Authors: Wanjarkhedkar Pankaj , Pingley Sonali , Shende Shaileshkumar , Kelkar Dhananjay , Parasnis Amit , Sambhus Mahesh , Phadake Girish , Hingmire Sachin , Kulkarni Padmaj , Deshmukh Chetan
Published: June 2021

Background Radiotherapy-induced oral mucositis (RIOM) in patients with head and neck cancer may lead to significant morbidity. OM may result in erythema, ulceration, and pseudomembrane formation. The usual time of onset is second or third week of radiotherapy (RT), after the doses of 16 to 18 Gy. OM may cause severe pain, significant weight loss, increased resource use, interruption or discontinuation of the treatment, and added cost of supportive care.

Materials and Methods Patients who underwent RT and chemoradiation (CTRT) for head and neck squamous cell carcinoma (HNSCC) from 2015 to 2016 were included. The patients who were treated with the add-on Ayurveda gargle regimen (AGR) of sapthachhadadi gandoosham were evaluated against patients treated with standard symptomatic care (SSC).

Statistical Analysis Chi-square test was used to compare the difference between the two groups in the present study with SPSS (SPSS version 20 for Windows package SPSS Science, Chicago, IL, USA). software.

Result Grade III to IV OM was lower in the AGR group when compared with the SSC group (p < 0.001). Onset of OM was significantly delayed in patients from the AGR group (p < 0.001).

Conclusion The AGR with sapthachhadadi gandoosham is effective in delaying the onset and reducing severity of OM in HNSCC, without compromising the rate of locoregional recurrence.
ROTEM Testing for Direct Oral Anticoagulants
Authors: Korpallová Barbora , Samoš Matej , Bolek Tomáš , Kühnelová Linda , Škorňová Ingrid , Kubisz Peter , Staško Ján , Mokáň Marián
Published: June 2021

Direct oral anticoagulants (DOACs) are increasingly used worldwide for the prevention of stroke in patients with atrial fibrillation and to prevent or treat venous thromboembolism. In situations such as serious bleeding, the need for urgent surgery/intervention or the management of a thromboembolic event, the laboratory measurement of DOACs levels or anticoagulant activity may be required. Rotational thromboelastometry (ROTEM) is a viscoelastic hemostatic assay (VHA) which has been used in emergencies (trauma and obstetrics), and surgical procedures (cardiac surgery and liver transplants), but experience with this assay in DOACs-treated patients is still limited. This article reviews the use of ROTEM in the setting of DOACs therapy, focusing on DOACs-associated bleeding and the use of this VHA for the management of reversal strategies for DOACs-associated anticoagulation.
COVID-19 and Antiphospholipid Antibodies: Time for a Reality Check?
Authors: Favaloro Emmanuel J. , Henry Brandon Michael , Lippi Giuseppe
Published: June 2021

Antiphospholipid antibodies (aPL) comprise a panel of autoantibodies that reflect a potential prothrombotic risk in several autoimmune conditions, most notably antiphospholipid (antibody) syndrome (APS). aPL can be divided into those that form part of the laboratory criteria for APS, namely, lupus anticoagulant (LA), as well as anticardiolipin antibodies (aCL) and anti-β2-glycoprotein I antibodies (aβ2GPI) of the immunoglobulin G and M classes, and those that form a group considered as “noncriteria antibodies.” The noncriteria antibodies include, for example, antiphosphatidylserine antibodies (aPS), antiprothrombin antibodies (aPT), and antiphosphatidylserine/prothrombin complex antibodies (aPS/PT). COVID-19 (coronavirus disease 2019) represents a prothrombotic disorder, and there have been several reports of various aPL being present in COVID-19 patients. There have also been similarities drawn between some of the pathophysiological features of COVID-19 and APS, in particular, the most severe form, catastrophic APS (CAPS). In this review, we critically appraise the literature on aPL and COVID-19. This is a companion piece to a separate review focused on LA. In the current review, we primarily concentrate on the so-called solid phase identifiable aPL, such as aCL and aβ2GPI, but also reflect on noncriteria aPL. We conclude that aPL positivity may be a feature of COVID-19, at least in some patients, but in general, identified “solid-phase” aPL are of low titer and not able to be well-linked to the thrombotic aspects of COVID-19. Also, most publications did not assess for aPL persistence, and where persistence was checked, the findings appeared to represent transient aPL. Importantly, high-titer aPL or multiple aPL positivity (including double, triple) were in the minority of COVID-19 presentations, and thus discount any widespread presence of APS, including the most severe form CAPS, in COVID-19 patients.
Evaluation of Two Phenotypic Methods for the Detection of Plasmid-Mediated AmpC β-Lactamases among Enterobacteriaceae Isolates
Authors: Mol P Ronni , Bindayna Khalid Mubarak , Shanthi Ganesan
Published: June 2021

Objectives AmpC β-lactamases are cephalosporinases that confer resistance to cephalothin, cefazolin, cefoxitin, penicillin, and β-lactamase inhibitor-β-lactam combinations. Even though the AmpC resistance is reported, but the accurate occurrence of AmpC β-lactamases in Enterobacteriaceae members is still unknown. Techniques to identify AmpC producers are still evolving but not yet optimized for the clinical laboratory. Here we aimed to compare the test performance of two different phenotypic methods, that is inhibitor-based assay using boronic acid and disk approximation test for AmpC detection in Enterobacteriaceae isolates from a tertiary hospital microbiology laboratory.

Materials and Methods The study includes 137 nonrepeat Enterobacteriaceae strains. Bacterial isolates, that yielded a zone diameter of less than 18 mm for cefoxitin by disk diffusion method were considered potential AmpC producers and further confirmed by phenotype methods—inhibitor-based assay using boronic acid and disk approximation test. A multiplex polymerase chain reaction was used to detect the most common plasmid-mediated AmpC genes: ACC, FOX, MOX, DHA, CIT, and EBC.

Results Of the 137 clinical isolates, 58 (42.33%) were cefoxitin resistant, while 53.4 and 18.9% of the cefoxitin-resistant isolates were positive by inhibitor-based assay and disk approximation test. Multiplex PCR detected 42 (30.6%) isolates with AmpC genes. Of the 42 isolates, the inhibitor-based assay detected 25 (59.5%) isolates, while the disk approximation test detected nine (21.4%) isolates.

Conclusion Our findings suggest that inhibitor-based assay using boronic acid can be used for the detection of the isolates that harbor AmpC β-lactamases. This method is cost-effective, simple to perform, and easy to interpret. Thus AmpC detection as a routine in clinical laboratories can help in appropriate therapeutic intervention and improved infection control.
Is Lupus Anticoagulant a Significant Feature of COVID-19? A Critical Appraisal of the Literature
Authors: Favaloro Emmanuel J. , Henry Brandon Michael , Lippi Giuseppe
Published: June 2021

The term “lupus anticoagulant (LA)” identifies a form of antiphospholipid antibodies (aPLs) causing prolongation of clotting tests in a phospholipid concentration-dependent manner. LA is one of the laboratory criteria identified in patients with antiphospholipid (antibody) syndrome (APS). The presence of LA in patients with APS represents a significant risk factor for both thrombosis and pregnancy morbidity. There have been several reports of similarities between some of the pathophysiological features of COVID-19 and APS, in particular the most severe form, catastrophic APS. There have also been many reports identifying various aPLs, including LA, in COVID-19 patients. Accordingly, a very pertinent question arises: “Is LA a feature of COVID-19 pathology?” In this review, we critically appraise the literature to help answer this question. We conclude that LA positivity is a feature of COVID-19, at least in some patients, and potentially those who are the sickest or have the most severe infection. However, many publications have failed to appropriately consider the many confounders to LA identification, being assessed using clot-based assays such as the dilute Russell viper venom time, the activated partial thromboplastin time (aPTT), and the silica clotting time. First, most patients hospitalized with COVID-19 are placed on anticoagulant therapy, and those with prior histories of thrombosis would possibly present to hospital already on anticoagulant therapy. All anticoagulants, including vitamin K antagonists, heparin (both unfractionated heparin and low-molecular-weight heparin), and direct oral anticoagulants affect these clot-based assays. Second, C-reactive protein (CRP) is highly elevated in COVID-19 patients, and also associated with severity. CRP can also lead to false-positive LA, particularly with the aPTT assay. Third, persistence of aPL positivity (including LA) is required to identify APS. Fourth, those at greatest risk of thrombosis due to aPL are those with highest titers or multiple positivity. Most publications either did not identify anticoagulation and/or CRP in their COVID-19 cohorts or did not seem to account for these as possible confounders for LA detection. Most publications did not assess for aPL persistence, and where persistence was checked, LA appeared to represent transient aPL. Finally, high titer aPL or multiple aPL positivity were in the minority of COVID-19 presentations. Thus, at least some of the reported LAs associated with COVID-19 are likely to be false positives, and the relationship between the detected aPL/LA and COVID-19-associated coagulopathy remains to be resolved using larger and better studies.
Investigation of High-Risk ST131 Clone in Extended Spectrum β-Lactamase–Producing Escherichia coli Isolates in Children
Authors: Bulut Mehmet E. , Hürkal Gülen , Dalgıç Nazan
Published: June 2021

Objective Antimicrobial resistance poses a serious threat to children's health. In recent years, high-risk Escherichia coli ST131 has become an important target for global surveillance studies. The E.coli ST131 clone is associated with extended spectrum β-lactamase (ESBL) production, as well as multidrug resistance and treatment failure. Studies on this clone in the pediatric age group are limited. We aim to investigate the rate of high-risk E. coli ST131 clone in ESBL-positive E. coli isolates obtained from pediatric patients.

Methods A total of 292 ESBL-positive E. coli isolates from clinical samples of pediatric patients was included in the study. MALDI-TOF MS system was used for bacterial identification. Susceptibility tests were performed using BD Phoenix automated system. ST131 detection was done by MALDI-TOF-MS. Fisher's exact test was used to compare the groups (significance <0.05).

Results A total of 292 isolates was analyzed. The high-risk ST131 clone was detected in 117 (40%) of the 292 ESBL-positive isolates. ST131 rates were found to be significantly higher in children under the age of 5 years compared with children over the age of 5 years (49.3 vs. 31.1%, p = 0.0019). Ciprofloxacin resistance was higher in ST131 isolates (45.6 vs. 31.7%; p < 0.05).

Conclusion The rate of the ST131 clone was found to be high in the pediatric population. The significantly high rate of resistance to ciprofloxacin, which is not commonly used in the pediatric population, in ST131 isolates reveals the importance of the spread of high-risk clones for the development of resistance.
High-resolution human mobility data reveal race and wealth disparities in disaster evacuation patterns
Authors: Deng Hengfang , Aldrich Daniel P. , Danziger Michael M. , Gao Jianxi , Phillips Nolan E. , Cornelius Sean P. , Wang Qi Ryan
Published: June 2021

Major disasters such as extreme weather events can magnify and exacerbate pre-existing social disparities, with disadvantaged populations bearing disproportionate costs. Despite the implications for equity and emergency planning, we lack a quantitative understanding of how these social fault lines translate to different behaviours in large-scale emergency contexts. Here we investigate this problem in the context of Hurricane Harvey, using over 30 million anonymized GPS records from over 150,000 opted-in users in the Greater Houston Area to quantify patterns of disaster-inflicted relocation activities before, during, and after the shock. We show that evacuation distance is highly homogenous across individuals from different types of neighbourhoods classified by race and wealth, obeying a truncated power-law distribution. Yet here the similarities end: we find that both race and wealth strongly impact evacuation patterns, with disadvantaged minority populations less likely to evacuate than wealthier white residents. Finally, there are considerable discrepancies in terms of departure and return times by race and wealth, with strong social cohesion among evacuees from advantaged neighbourhoods in their destination choices. These empirical findings bring new insights into mobility and evacuations, providing policy recommendations for residents, decision-makers, and disaster managers alike.
Quantization effects in semiconductor nanostructures and singlet fission in molecular chromophores for photovoltaics and solar fuels
Authors: Nozik Arthur J.
Published: June 2021

Hot carriers in semiconductors are electrons and/or holes that have energies greater than carriers that reside at the top and bottom of the conduction and valence bands, respectively; the latter carriers are in equilibrium with the lattice and have a temperature equal to the lattice (ambient) temperature. Hot carriers are created in semiconductors upon the absorption of photons with energies greater than the bandgap. The excess energy above the bandgap energy is in the form of kinetic energy. The hot carriers can cool to the lattice temperature via electron–phonon scattering and establish separate Boltzmann distributions for electrons and holes at the band edges. Thus, upon cooling, the excess kinetic energy of the hot carriers is transformed into heat and is unavailable to be converted into electrical or chemical free energy in a solar photon-converting cell. This hot-carrier cooling process significantly limits the maximum possible power conversion efficiency (PCE) of the free energy of solar photons into electrical free energy or chemical free energy in chemical bonds of fuels. However, if hot-carrier cooling can be slowed such that the hot carriers can be extracted before cooling to create higher photovoltages, or utilized to create additional electron-hole pairs through carrier multiplication, then beneficial use can be made of the excess energy of hot carriers and the maximum thermodynamic PCE can be dramatically increased. Quantization effects in semiconductor nanostructures, unique properties of some bulk semiconductors, and exciton multiplication in both semiconductors and molecular chromophores that undergo singlet fission have shown a path forward for potential dramatic increases in the PCEs of solar photons into electricity and solar fuels. The status, history, and future promise of the science and technology of these future approaches for different types of photovoltaic cells and cells for solar fuels will be discussed.
Growth of centimeter-scale single crystal MoO3 ribbons for high performance ultraviolet photodetectors
Authors: Wu Di , Qi Dianyu , Liu Jidong , Wang Zixuan , Hao Qiaoyan , Hong Guo , Liu Fei , Ouyang Fangping , Zhang Wenjing
Published: June 2021

Molybdenum oxides have attracted much interest due to their unique electronic properties. Here, we report a convenient and efficient method to synthesize centimeter-scale single crystal of MoO3 ribbons through an atmospheric pressure physical vapor deposition approach. Optical microscopy, atomic force microscopy, high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction, and x-ray diffraction measurements reveal that the MoO3 ribbons grow along the MoO3⟨100⟩ direction and the top surface is MoO3(010) plane. Raman spectroscopy, x-ray photoelectron spectroscopy, and cross-sectional HRTEM results disclose that the surface of MoO3 ribbons can be transformed from MoO3 to MoO2 through H2 annealing treatment forming MoO2/MoO3 heterostructure. We found that the conductance and ultraviolet photoresponsivity of the MoO3 ribbons can be improved by ∼11 and ∼5 orders of magnitude, respectively, after H2 annealing treatment, which will be helpful for the applications of MoO3 in the optoelectronic field.
Parity-time-symmetric rational vector rogue waves of the n-component nonlinear Schrödinger equation
Authors: Zhang Guoqiang , Ling Liming , Yan Zhenya , Konotop Vladimir V.
Published: June 2021

Extreme events are investigated in the integrable n-component nonlinear Schrödinger (NLS) equation with focusing nonlinearity. We report novel multi-parametric families of rational vector rogue wave (RW) solutions featuring the parity-time (PT) symmetry, which are characterized by non-identical boundary conditions for the components that are consistent with the degeneracy of n branches of Benjamin–Feir instability. Explicit examples of PT-symmetric rational vector RWs are presented. Subject to the specific choice of the parameters, high-amplitude RWs are generated. The effect of a small non-integrable deformation of the 3-NLS equation on the excitation of vector RWs is discussed. The reported results can be useful for the design of experiments for observation of high-amplitude RWs in multi-component nonlinear physical systems.
Mechanisms of gas temperature variation of the atmospheric microwave plasma torch
Authors: Jie Ziyao , Liu Cheng , Huang Shiyang , Zhang Guixin
Published: June 2021

The gas temperature is a key parameter that affects the process of microwave plasma chemistry in industrial applications. Based on the molecular emission spectrometry of the A2Σ+→X2Πr electronic system of OH radicals, the gas temperature of the atmospheric air microwave plasma core at different absorbed microwave power levels, gas flow rates, gas humidities, and volume fractions of CO2 in air was analyzed. In the experiment, the absorbed microwave power, gas flow rate, gas humidity, and volume ratio of CO2 in air was varied from 560 to 1750 W, 10 to 24 l min−1, 30% to 95%, and 0% to 40%, respectively. Moreover, the axial gas temperature distribution of the plasma torch was measured. The experimental results showed that (i) the plasma gas temperature mainly ranged from 4000 to 7000 K, (ii) the plasma gas temperature rose with increasing absorbed microwave power but was hardly affected by the feeding gas flow rate, (iii) the plasma gas temperature decreased by ∼400 K for every 20% increase in the fraction of CO2 in air and decreased with increasing gas humidity, and (iv) the plasma torch gas temperature decreased along the axial direction. Due to the lack of a prevailing microwave discharge theory, an in-depth analysis of the mechanisms of gas temperature variation was performed based on the heat balance equation.
One-dimensional semiconductor nanostructures grown on two-dimensional nanomaterials for flexible device applications
Authors: Hong Young Joon , Saroj Rajendra K. , Park Won Il , Yi Gyu-Chul
Published: June 2021

This Perspective presents a review of current research activities on one-dimensional (1D) semiconductor nanostructures grown on two-dimensional (2D) nanomaterials for flexible electronic and optoelectronic device applications. For hybrid-dimensional nanostructures, 1D nanostructures exhibit excellent material characteristics, including high carrier mobility and radiative recombination rate as well as long-term stability, while 2D layers show good optical transparency, mechanical flexibility, and electrical characteristics. Accordingly, the versatile and fascinating properties of 1D nanostructures grown on 2D layers enable the fabrication of high-performance optoelectronic and electronic devices even in transferable, flexible, or stretchable forms. We initially present a variety of 1D/2D hybrid nanostructures and their preparation methods, followed by a discussion of techniques for fabricating aligned 1D nanostructure arrays on 2D layers and their heterostructures. Furthermore, we discuss a wide range of devices based on the 1D/2D hybrid nanostructures. These devices include light-emitting devices, photodetectors, transistors, and pressure sensors. Several important issues, including 1D/2D junction properties and device fabrication processes for device applications, are also addressed. We conclude with personal remarks on the issues and perspectives for research on 1D/2D hybrid nanostructures for more sophisticated device applications.
Development of a novel model by combining the intermediate blocking and cake filtration models for assessment of the prevailing fouling mechanism in a microbial fuel cell-facilitated membrane bioreactor
Authors: Hou Bin , Chen Jiajun , Li Ying , Liu Pengxiao , Liu Yao , Lu Jing
Published: June 2021

This study was carried out on a membrane bioreactor (MBR) facilitated with an electric field provided by a microbial fuel cell (MFC), which effectively reduced membrane contamination and extended the operation time of the MBR from 18 to 24 days. To understand the theory of membrane fouling in the MFC-MBR, a novel model based on the operation of the MFC-MBR was proposed with the modification of the classical filtration models to assess the membrane fouling. With this model, a two-phase membrane fouling development was observed, which was initially dominated by the intermediate-blocking model and then gradually changed to cake filtration. In the combined model of two-phase development, fouling was significantly mitigated by the electric field in phase 1, but its function was barely observed in phase 2. The combined model fit well with the experimental data, which could predict membrane fouling in the application of the MFC-MBR.
A self-alignment method for gravitational apparent acceleration identification and accelerometer bias estimation based on repeated navigation solution
Authors: Huang Yongjiang , Liu Xixiang , Wang Zixuan , Wu Xiaoqiang , Liu Wei
Published: June 2021

Estimating inertial measurement unit error without any external reference information has always been a difficult problem. The method based on the reconstruction of the gravitational apparent motion in the inertial frame can estimate the accelerometer bias, but a long identification time is needed to get high alignment accuracy. In order to reduce the convergence time and improve the accuracy of estimation, a fast estimation method based on repetitive navigation under the excitation of swing motion is proposed. Two data processing methods, the forward–forward loop and the backward–forward loop, are studied and compared in this paper. In addition, the influence of data length on the experiment result was analyzed. The simulation and experimental results show that the forward–forward loop calculation cannot solve the contradiction between speed and accuracy, while the backward–forward loop calculation can effectively estimate the accelerometer bias and realize self-alignment, with a short alignment time and high alignment accuracy.
Study on vehicle drag reduction simulation based on Suzen–Huang model
Authors: Wang Zewei , Hu Xingjun , Mao Jingming , Lan Wei , Hui Zheng , Li Sheng
Published: June 2021

In the past numerical simulation of plasma and fluid coupling, the usually used Suzen numerical simulation model has the defect that the error increases with the increase in excitation voltage. The static test of the ionic wind is used to modify the parameters of the Suzen simulation model, and it applied the modified Suzen model to the flow control of the automobile external flow field, which shows good consistency with the wind tunnel test results. Results show that the Suzen model modified by the static test results of the ionic wind is suitable for different excitation voltage conditions. The corrected body force and charge density distribution conform to the change trend of plasma discharge, and the error between the maximum ionic wind velocity obtained by simulation and the test result is within 4%; the modified Suzen model is successfully applied to the plasma flow control of automobile aerodynamic drag reduction. The results show that the exciter suppresses the generation of periodic separation vortices in the tail of the model, which makes the vorticity in the wake significantly decrease, thereby reducing the energy dissipation and the aerodynamic drag of the model. Through the research in this paper, the modified Suzen model reduces the simulation error. Plasma flow control technology is applied to the field of automobile aerodynamic drag reduction, which has accumulated important experience methods and data foundation for the engineering application of this technology. It also provides new methods for improving vehicle aerodynamic performance and fuel economy.
Nonlinear explosive magnetic reconnection in a collisionless system
Authors: Hoshino Masahiro
Published: June 2021

The debate surrounding fast magnetic energy dissipation by magnetic reconnection has remained a fundamental topic in the plasma universe, not only in the Earth's magnetosphere but also in astrophysical objects such as pulsar magnetospheres and magnetars, for more than half a century. Recently, nonthermal particle acceleration and plasma heating during reconnection have been extensively studied, and it has been argued that rapid energy dissipation can occur for a collisionless “thin” current sheet, the thickness of which is of the order of the particle gyroradius. However, it is an intriguing enigma as to how the fast energy dissipation can occur for a “thick” current sheet with thickness larger than the particle gyroradius. Here we demonstrate, using a high-resolution particle-in-cell simulation for a pair plasma, that an explosive reconnection can emerge with the enhancement of the inertia resistivity due to the magnetization of the meandering particles by the reconnecting magnetic field and the shrinkage of the current sheet. In addition, regardless of the initial thickness of the current sheet, the timescale of the nonlinear explosive reconnection is tens of the Alfvén transit time.
Vertical force generation of a vectorial thruster that employs a rigid flapping panel
Authors: Hu Haizhou , Wang Yankui
Published: June 2021

The vertical force generation and flow features of a flapping panel that employs combined motion of horizontal oscillation, longitudinal rotation, and leading-edge-based pitching motion were investigated numerically. The sole vertical force generation is realized by combining the horizontal oscillation and longitudinal rotation, while the vertical force and forward thrust are obtained simultaneously by employing the combined motion of the horizontal oscillation, longitudinal rotation, and pitching motion about the leading edge of the panel. The effects of the phase shift (Ψ) of the longitudinal rotation and the amplitudes of the longitudinal rotation and pitching motion are investigated and discussed, respectively. Results show that the phase shift determines the instantaneous attitude of the panel and influences the directions of the instantaneous generated forces and thus plays an important role in the vertical force generation. The panel could generate stable forward thrust while maintaining the pitching motion constant and adjusting the longitudinal rotation amplitude, and in the meantime, the vertical force increases linearly with the rotation amplitude. On the other hand, the vertical force may change to the opposite direction when the longitudinal rotation is kept constant and the pitching amplitude is adjusted. The results of the current research show the potential of employing these kinds of combined motions to fish-tail-mimic propulsors of robotic fishes that pursue high maneuverability.
Stress engineering of boron doped diamond thin films via micro-fabrication
Authors: Isa Fabio , Best James P. , Marzegalli Anna , Albani Marco , Comte Christophe , Kruzic Jamie J. , Bendavid Avi
Published: June 2021

In this paper, a novel approach is presented to tailor the stress properties of diamond thin films via boron doping and micro-fabrication of bridges using focused ion beam milling. The experimental data, based on detailed confocal micro-Raman investigations, are supported and interpreted through finite element method calculations of the stress distribution at mechanical equilibrium. These results indicate that appropriate design of microbridge geometries, together with boron doping, would allow the material stress to be largely enhanced or diminished compared to non-patterned thin films. Our approach, together with a deterministic incorporation and positioning of diamond color centers, may open novel opportunities to tailor the optical and spin properties of diamond-based quantum devices through stress engineering.
Sound absorption of petal shaped micro-channel porous materials
Authors: He Wei , Liu Maolin , Peng Xiangjun , Xin Fengxian , Lu Tian Jian
Published: June 2021

Experiments demonstrated that surface roughness could significantly improve the sound absorption performance of porous materials. In this study, to quantitatively explore the underlying physical mechanisms, porous materials with roughened pore surfaces are modeled as a bundle of parallel petal shaped tubes, so that relevant acoustic transport parameters, namely, viscous permeability, thermal permeability, tortuosity, viscous characteristic length, and thermal characteristic length, can be theoretically predicted. Multi-scale numerical simulations are implemented to validate the theoretical predictions, with good agreement achieved. Compared with smooth tubes, petal shaped tubes reduce the viscous and thermal characteristic lengths as well as the viscous and thermal permeabilities, resulting in enhanced sound absorption over a wide frequency band.
Bridge expansion after coalescence of two droplets in air: Inertial regime
Authors: Chireux Véronique , Tordjeman Philippe , Risso Frédéric
Published: June 2021

When two liquid droplets approach at negligible velocity in air, their coalescence spontaneously occurs by jump-to-contact instability and a connecting bridge joining the two facing interfaces at the nanoscale is created. We report experimental investigations of the expansion of this initial bridge by means of high-speed imaging. By considering droplets of water, polydimethylsiloxane, or paraffin of a few hundred micrometers, we investigate regimes where inertia takes a major role. Depending on the Ohnesorge number (Oh), the dynamics of the bridge differs a lot. For Oh ≈1, the initial flow is rapidly attenuated and the connecting bridge between the two droplets adopts a smooth parabolic shape. The maximum interface curvature and the minimum liquid pressure remain at the bridge center. The expansion is thus caused by the capillary pressure that drives the fluid toward the center. At small Oh, in the inertial regime, the length of the initial bridge grows at constant speed and the bridge expansion can be described by the propagation of nondispersive capillary wave packets. The central part of the bridge takes a cylindrical shape connected to the droplets by a narrow region of very large curvature. At the resolved scale, the interface exhibits slope discontinuities. By considering dihedral potential flows that result in the presence of the slope discontinuities, we show that the apparent angle made by the interface controls the flow rate that enters the bridge and thus determines its radial expansion.
Experimental chaotic synchronization for coupled double
pendula
Authors: Dudkowski Dawid , Wojewoda Jerzy , Czołczyński Krzysztof , Kapitaniak Tomasz
Published: June 2021

In this paper, we experimentally verify the phenomenon of chaotic synchronization in coupled forced oscillators. The study is focused on the model of three double pendula locally connected via springs. Each of the individual oscillators can behave both periodically and chaotically, which depends on the parameters of the external excitation (the shaker). We investigate the relation between the strength of coupling between the upper pendulum bobs and the precision of their synchronization, showing that the system can achieve practical synchronization, within which the nodes preserve their chaotic character. We determine the influence of the pendula parameters and the strength of coupling on the synchronization precision, measuring the differences between the nodes’ motion. The results obtained experimentally are confirmed by numerical simulations. We indicate a possible mechanism causing the desynchronization of the system’s smaller elements (lower pendula bobs), which involves their motion around the unstable stationary position and possible transient dynamics. The results presented in this paper may be generalized into typical models of pendula and pendula-like coupled systems, exhibiting chaotic dynamics.
Population genetics, demographics and implications for conservation of
Authors: Roberts R. , Lamont R. W. , Simmons C. L. , Leiper G. , Guymer G. P. , Shapcott A.
Published: June 2021

Brachychiton sp. Ormeau (L.H. Bird AQ435851), commonly known as the Ormeau bottle tree, is listed as Critically Endangered under the Environment Protection and Biodiversity Conservation Act 1999. Undescribed and extremely rare, it is known only from several sites within a very small geographic range near Ormeau in south-east Queensland. Using microsatellite markers developed for this study, we found Brachychiton sp. Ormeau to be genetically distinct from several closely related species, confirming unique specific status. We also assessed levels of genetic variation found within B. sp. Ormeau subpopulations to provide recommendations for recovery projects. The species exhibited low levels of variation (He = 0.065); however, no evidence of inbreeding (F = –0.290). We infer that the species’ current restricted range and low genetic diversity is due to a combination of the effects of well documented climate shifts across the Plio-Pleistocene, exacerbated by extensive rates of relatively recent and ongoing human-mediated habitat loss. Our results suggest that, to enhance the long-term viability of B. sp. Ormeau, the most effective recovery strategies include the protection and restoration of the existing remnant habitat, as well as enhancement of local subpopulations and existing isolated plants, with additional plants to increase the genetic diversity.
Reversible Fluorescence Switching of Donor–Acceptor Type Bipyridines by Simple Protonation–Deprotonation Equilibria
Authors: Mubeena Shaik , N Meghana , Annapareddy Gayatri , Chen Yi-Sheng , Sarma Monima , Wong Ken-Tsung
Published: June 2021

This article describes the switchable fluorescence of a series of donor–acceptor type 2,2′-bipyridines. The original bipyridine molecules have four protonation sites – two on the amino donor sites and two on the pyridine acceptor cores. These nitrogen-containing sites are selectively protonated by suitable acids and the protonation influences the electronic conjugation and structure of the chromophores. Consequently, the emission characteristics of the molecules are affected, and this behaviour is reversible, i.e. the neutral original species are regenerated by the addition of an equivalent amount of base. The switchable behaviour of these compounds is accompanied by a visible colour change of the relevant solutions.
Fluorescent Reporters for Antimicrobial Peptides
Authors: Hong Yuning , Li Wenyi
Published: June 2021

Antimicrobial peptides (AMPs), a part of the natural defence against pathogens, have been considered as alternative antibiotics to combat the increase of antimicrobial resistance (AMR). Given the advanced development of fluorescent probes, extensive research has been focussed on understanding the physiological processes of the interaction between AMPs and bacteria. To better guide the choice of suitable fluorescent reporters for the mechanism study of AMPs, in this review, we summarise a toolbox of commonly used fluorescent reporters for AMP studies, including intrinsic fluorescent reporters, conventional fluorophores, and recently developed aggregation-induced emission (AIE) fluorogens.
A magnon scattering platform
Authors: Zhou Tony X. , Carmiggelt Joris J. , Gächter Lisa M. , Esterlis Ilya , Sels Dries , Stöhr Rainer J. , Du Chunhui , Fernandez Daniel , Rodriguez-Nieva Joaquin F. , Büttner Felix , Demler Eugene , Yacoby Amir
Published: June 2021

Significance

This work describes a general scattering platform that uses magnons to explore the underlying properties of target materials. In this work we show how both phase and amplitude of magnons can be imaged using a nitrogen vacancy center magnetometer and how the scattered pattern of waves can be used to infer geometric and magnetic properties of a target material. To demonstrate this new experimental methodology we use a permalloy disk as our target and show that even with such a simple target unexpected behavior is observed. In addition, we provide a theoretical framework to reconstruct the properties of the target.
Which variables may affect underwater glide performance after a swimming start?
Authors: Hermosilla Francisco , Yustres Inmaculada , Psycharakis Stelios , Santos del Cerro Jesús , González‐Mohíno Fernando , González‐Rave José M.
Published: June 2021

The underwater phase is perhaps the most important phase of the swimming start. To improve performance during the underwater phase, it is necessary to improve our understanding of the key variables affecting this phase. The main aim of this study was to identify key kinematic variables that are associated with the performance of an underwater glide of a swimming start, when performed at streamlined position without underwater undulatory swimming. Sixteen experienced swimmers performed 48 track starts and 20 kinematic variables were analysed. A multiple linear regression analysis was carried out to explore the relationship between glide performance (defined as glide distance) and the variables that may affect glide performance. Four variables in the regression model were identified as good predictors of glide distance: flight distance; average velocity between 5 m and 10 m; and maximum depth of the hip. The results of the present study help improve our understanding of underwater glide optimisation and could potentially facilitate improvement of overall start performance.