bluuebunny/crossref_metadata_2025 huggingface dataset:
Estimation of infection risk through airborne transmission in large open spaces with different air distributions
Authors: Shen Jialei , Nabutola Kaloki , Birnkrant Michael J. , McKinney Peter J. , Dong Bing , Zhang Jianshun
Published: August 2022

Respiratory diseases such as COVID-19 can be spread through airborne transmission, which is highly dependent on the airflow pattern of the studied room. Indoor air is typically not perfectly mixed even using a mixing ventilation, especially in large spaces. Airflow patterns in large open spaces such as hotel banquet rooms and open plan offices, are of particular concern, as these spaces usually accommodate more occupants and thus have the potential to spread diseases more rapidly leading to outbreaks. Therefore, understanding airflow patterns in large open spaces can help to estimate the detailed infection risk at certain locations in the space, which can prevent the spread of virus and track the potential new infections. This study estimated airflow patterns in a typical banquet room under theatre and banquet scenarios, and a large open plan office using computational fluid dynamics (CFD) simulations. Typical ventilation and air distribution approaches, as well as room layouts and occupant configurations in these scenarios were studied and applied in simulations. According to current results, the air distribution in a typical hotel banquet room with mixing ventilation can be very complicated, particularly for the banquet scenario. For a typical theatre scenario, under typical ventilation design, people sitting in the middle and lateral area were exposed to the highest infection risk. The front rows may be exposed to short-range transmission as well. For a banquet scenario, people sitting on the same table were more likely to be cross contaminated. But cross-table infection was still possible. The results can provide guidance on designing ventilation and air distribution approaches in large spaces with similar settings.
CFD modelling of a pulsed jet formed during an idealized isolated cough
Authors: Zasimova Marina , Ris Vladimir , Ivanov Nikolay
Published: August 2022

The current contribution presents the results of calculations of a pulsed jet formation during a single cough based on the recent test by Fabregat et al. (2021) where the DNS of an idealized isolated cough was performed. Two approaches for turbulence modeling were applied – the Large Eddy Simulation (LES) and the Unsteady Reynolds-Averaged Navier-Stokes (URANS). The particles propagation was described with the Lagrangian formulation, both with and without interaction with the continuous phase. Unsteady changes in the airflow structure of the pulsed jet are analyzed and discussed, with respect to the accuracy of the turbulence modeling method used. The calculated data show that during the period of 1.5 s the strong pulsed jet dissipates and transforms to a puff. By that instant, the puff front propagates over the distance of up to 0.5 m (URANS data) and 0.6 m (LES data). During the initial period, the URANS data differ from the LES data; nevertheless, at subsequent time instants, the velocity and temperature fields are similar.
Associations between indoor VOCs and childhood asthma in Shanghai, China: an analysis stratified by frequency of window opening during night
Authors: Zhou Lele , Huang Chen , Lu Rongchun , Wang Xueying , Zou Zhijun
Published: August 2022

Few studies pay attention to the possible associations between indoor VOCs and childhood asthma in Shanghai considering the effect of household ventilation. From March 2013 to December 2014, we collected air samples from 358 children's bedrooms in Shanghai, China. Information on childhood asthma, environmental exposures, and lifestyle behaviors was collected. Two-sample of Mann-Whitney U test, bivariate logistic regressions, and multiple logistic regression were used to obtain the association between VOCs and childhood asthma. Association analysis stratified by frequency of window opening during night was conducted to explore its possible effect on the target association. High concentrations of toluene and dodecane were significantly associated with childhood wheeze, and a high concentration of toluene was significantly associated with diagnosed asthma. In the bedrooms with low frequency of window opening during night, high concentrations of toluene, dodecane, and TVOC were significantly associated with childhood wheeze, and a high concentration of toluene was significantly associated with diagnosed asthma. Our results indicate that exposure to VOCs may be a risk factor for childhood asthma, especially in the bedrooms with poor ventilation during night. Family avoidance behaviors of household ventilation should be considered in the study of associations of household VOCs with childhood asthmatic symptoms.
Health Survey of the Elderly in Huizhou Traditional Villages
Authors: Bian Mengyuan , Zhao Wenwen , Huang Zhijia , Kou Zunli , Zhou Heng
Published: August 2022

This work aims to establish a health self-assessment questionnaire from three aspects of physical health, mental health, and social health through the improvements to the Mos 36-item Short-Form Health Survey, and conduct a questionnaire survey of 219 the elderly in Zhaji village and Hou’ an village to find out the healthy condition of the elderly at home in rural areas in Southern Anhui province. The survey results found that the general health status of the elderly living at home in rural areas in Southern Anhui province is relatively better, with a total score mean of 74.08, the mental health is best, and the social health is worst. The indicators with the lowest percentage of “good” votes are: physical health is energy (PH9), mental health is sleep (MH5), and social health is participation in the elections (SH2). The Body Mass Index (BMI) and health self-care ability of the elderly are good. Similarly, the Body Mass Index (BMI) and health self-care ability of the elderly could be better. The survey results show that the indoor environment of Huizhou architecture has benefits for the health of the elderly, so it can be referred to in the subsequent construction of the elderly.
The gradient-boosting decision tree model can predict the concentration of PAEs in children bedroom
Authors: Sun Chanjuan , Wang Qinghao , Huang Chen , Li Jingguang , Zhang Jialing , Zou Zhijun , Tian Lang
Published: August 2022

Exposure of phthalate has adverse effects on child health. Currently, the field measurement on PAEs concentration in children’s bedrooms were limited, and the test of PAEs is laborious. Based on the data of home detection in 454 residences from March 2013 to December 2014 in Shanghai, the association of PAEs in children's bedroom and building characteristics, residents’ lifestyle and indoor environment characterization were built by Spearman correlation. According to the Spearman correlation coefficient method, the concentration of PAEs, such as residential area was significantly correlated with DMP, BBP and DiBP in children’s bedroom (sig <0.05, sig <0.01, sig <0.01; r> 0), and the use of chemicals was significantly associated with DEP and DiBP in children’s bedroom (sig <0.05, sig <0.05; r> 0). Then a gradient-boosting decision tree model with higher prediction accuracy is established. The influencing factors of the studied PAEs were determined by comprehensive consideration of the current study and literature review. 11 influencing factors of PAEs concentrations from three aspects were finally established in this study. The training model of GBDT has a reasonable accuracy( R2>0.9). This paper provides a reference for the prediction of PAEs concentration in the residential bedroom and the influence degree of influencing factors.
Gaseous Pollutent Source Term Estimation Based on Adjoint Probability and Regularization Method
Authors: Jing Yuanqi , Gu Zhonglin , Li Fei , Zhang Kai
Published: August 2022

Fast and accurate identification of source locations and release rates is particularly important for improving indoor air quality and ensuring the safety and health of people. Existing methods based on adjoint probability are difficult to distinguish the release rate of dynamic sources, and optimization algorithms based on regularization are limited to analysing only a small amount of potential pollutant source information. Therefore, this study proposed an algorithm combining adjoint equations and regularization models to identify the location and release intensity of pollutant sources in the entire computational domain of a room. Based on the validated indoor CFD computational model, we first obtained a series of response matrices corresponding to the sensor position by solving the adjoint equation, and then used the regularization method and Bayesian inference to extrapolate the release rate and location of dynamic pollutant source in the room. The results shown that the proposed algorithm is convenient and feasible to identify the location and intensity of the indoor pollutant source. Compared with the real source intensity, the identification of constant source intensity is lower than the error threshold (10%) in 97.4% of the time nodes, and the identification of periodic source is lower than the error threshold (10%) in 95.4% of the time nodes. This research provides a new method and perspective for the estimation of indoor pollutant source information.
Analysis of Indoor Particle Diffusion in Attached Jet Air Supply System
Authors: Zhuang Zhaoyi , Zhao Jiahui , Yang Xiu , Shen Wenzeng , Lv Chaoqun , Shao Wei , Zhang Chuntian
Published: August 2022

With the change of the installation position of the radiant panel, the indoor air distribution formed by the attached jet air supply will also change, which will affect the diffusion distribution of indoor particulate matter. Through numerical simulation, the influence of indoor air distribution formed by attached jet air supply on the diffusion distribution of aerosol particles released by human body is studied. It is found that within 0 ~ 300s, 97.2% ~ 98.5% of the aerosol particles of human body jet are captured by the wall, and only a small part of fine particles exists in the air in the form of suspended solids. The final particle concentration of wall attached air supply is the lowest, and the effect of roof attached air supply is in the middle. The indoor particle concentration of wall attached air supply with deflector is higher than that of other forms at the same time in 0 ~ 300s.
Numerical Analysis on Performance of Different Ceiling Coverage of fan Filter Units in Semiconductor Fabs
Authors: Zhao Jiaan , Li Xianting , Xu Wei
Published: August 2022

In practical semiconductor fabs engineering, in order to reduce the investment cost, low coverage rate of FFUs is usually adopted and the air supply velocity is high, which brings high resistance to the filter mounted at FFU’s outlet. If a higher ceiling coverage and lower air velocity speed are used, the resistance may be significantly reduced and remarkable energy saving benefits can be obtained. In this study, CFD technology was adopted to simulate airflow in a semiconductor fab and air circulation resistance was obtained by theoretical calculation. Four ceiling coverage of FFUs, 25%, 50%, 75%, 100%, were studied under the condition of same air volume. The particle concentrations and payback period were analysed. The results show that (1) with the increase of the coverage rate, the concentration in most areas decreases significantly while only a small increase in the local area around occupant, and the particle concentration still meets the requirement; (2) adopting high coverage rate for transformation, the initial investment of FFUs increases slightly and the operating cost decreases significantly, and the payback period is only 1.1-2.3 years when 25% coverage rate is transformed into 37.5% - 75%.
Experimental Study on Structure and Performance of Dedusting Filter Material Modified by Reducing Graphene Oxide Spraying
Authors: Li Ming , Fan Yuesheng , Zhang Xin , Wang Huan , Cui Yong , Xue Kexin , Gan Weikang
Published: August 2022

With the continuous improvement of social requirements for air quality, industrial dedusting standards are becoming more and more stringent. Bag dust collector is one of the most commonly used and fastest technological dedusting equipment in industrial dedusting places.The filter bag is the core part of the bag filter, and the post-treatment of the filter bag is a common method to improve the performance of the bag filter.In this paper, air spraying method was used to post-treat four kinds of commonly used bag filter bags: polyimide fiber, polyphenylene sulfide fiber, glass fiber needle felt and flumex high temperature needle felt. The structural parameters and performance parameters of four new composites after post-treatment were compared and analyzed.The results showed that a layer of reduced graphene oxide coating was formed on the surface of the modified filter bag. After comprehensive comparative analysis, the reduction effect of graphene oxide composite with polyphenylene sulfide fiber (PPS) is the best. Under the filtration velocity of 0.8m/s, the filtration efficiency of PM1.0, PM2.5 and PM10 increased by 7.3%, 7.6% and 8.2%, respectively. The fiber porosity decreased from 98.36% to 98.18%. The resistance is basically unchanged, and the influence of resistance does not need to be considered when it is used. This study provides a reference for the post-treatment method of the filter bag of the dust collector.
Influence of ventilation on airborne fungi in greenhouses: A case study of tomato greenhouses
Authors: Xiong Jing , Wu Dingmeng , Zhang Ying , Li Angui , Hou Yicun , Huang Lin , Lei Wenjun , Zhang Linhua , Xiong Can , Fan Xianglin , Li Anjing , Li Minqiang
Published: August 2022

With the rapid development of greenhouses, the indoor air quality, particularly airborne microorganisms, is closely related to the health of farmers and needs more attention. In this study, the concentrations of airborne fungi at seedling, fruiting and harvesting stages in typical tomatoes greenhouses were tested. Temperature, relative humidity and the microbial concentrations were analysed. It was found that the dominant fungal genera are Aspergillus and Cladosporium, no matter it was in which growth stage. Ventilation is an effective way to reduce the concentrations of airborne fungi through dilution and decrease the relative humidity.
An Experimental Investigation on Indoor Air Pressure Performance of Multi-compartment Pharmacy Cleanroom under Local Fume Hood Operating Scenario
Authors: Chen Jiujiu , Ma Xiaojun , Li Chunwang
Published: August 2022

The control of indoor air pressure is very important in cleanroom operation, because of its sensitiveness of the risks from contaminants dispersion. Especially in pharmaceutical cleanrooms, since there always exist multiple compartments, the parametric stability of indoor air pressure is the key-point of operation control. When a fume hood in cleanroom running, the exhaust air volume changes greatly and then cause indoor pressure oscillating. Meanwhile, this scenario of fume hood running is often occurred because of manufacturing process need. However, the performance pattern of pressure is not clear when fume hood switches on or off. Therefore, the control strategy might be inefficient and even invalid. In this paper, the performance of indoor air pressure of multi-compartment cleanrooms under fume hood operating scenario is measured and analysed by experimental investigation method. The works of this paper might help understanding the performance of pressure variation in cleanrooms when disturbances occur and change. And the conclusions of this paper could be references for the design and operation strategies of multi-compartment cleanrooms.
Risk Factors of Loss of Knee Range of Motion after Primary Anterior Cruciate Ligament Reconstruction following Preoperative Recovery of Knee Range of Motion
Authors: Yokoe Takuji , Tajima Takuya , Yamaguchi Nami , Morita Yudai , Chosa Etsuo
Published: August 2022

The loss of knee range of motion (ROM) is not an uncommon complication after anterior cruciate ligament reconstruction (ACLR). However, the risk factors of loss of knee ROM remain debatable. The purpose of this study was to evaluate the incidence and risk factors of loss of knee ROM at 12 months after primary ACLR performed after regaining full knee ROM preoperatively. Consecutive patients who underwent primary ACLR after regaining full ROM between January 2014 and January 2020 were retrospectively reviewed. Patients who received a surgical arthrolysis within 12 months after ACLR or those who had a loss of knee ROM at 12 months postoperatively were defined as the loss of ROM group. Possible risk factors of loss of knee ROM, including patient demographic, preoperative, surgical, and postoperative factors, were assessed. The notch wide index and radiographic parameters of the tibial spines; medial tibial spine height/tibial length (TL), lateral tibial spine height (LTSH)/TL, and tibial spine width (TSW)/TL, were also assessed. A total of 141 patients (141 knees) were included (mean age, 25.8 ± 11.4 years; male/female, 56/85). Of the 141 patients, three received surgical arthrolysis within 12 months, and 23 had a loss of knee ROM at 12 months after ACLR. On comparing patients with and without loss of knee ROM, significant differences were found in the age (p = 0.04), LTSH/TL (p = 0.02), and TSW/TL (p = 0.02). A multivariate regression analysis showed that the age (odds ratio [OR]; 1.05, 95% confidence interval [CI]: 1.01–1.09, p = 0.02), LTSH/TL (OR: 1.44, 95% CI: 1.01–2.1, p = 0.04), and TSW/TL (OR: 0.79, 95% CI: 0.65–0.97, p = 0.02) were identified as significant independent risk predictors of loss of knee ROM. This study showed that the incidence of loss of knee ROM at 12 months after primary ACLR was 18.4% (26/141). An older age, a higher LTSH/TL, and a smaller TSW/TL may be associated with loss of knee ROM at 12 months after ACLR.
Advancements in Interventional Oncology of the Chest: Transarterial Chemoembolization and Related Therapies
Authors: Lorenz Jonathan M. , Navuluri Rakesh
Published: August 2022

While embolization therapy has been used for many years in the treatment of nonmalignant diseases of the chest, such as pulmonary arteriovenous malformation treatment and bronchial artery embolization for hemorrhage, the application of transarterial techniques to the treatment of chest neoplasms is relatively uncommon. Extrapolating from transarterial chemoembolization techniques used for liver malignancy, investigators have recently sought to expand the indications for transarterial techniques from the control of symptoms such as bleeding to the control of disease progression and potentially survival benefit in patients with malignancies in the chest. This article provides an overview of the current embolotherapy techniques used in the treatment of patients with thoracic malignancies.
Bronchial Artery Embolization
Authors: Kaufman Claire S. , Kwan Sharon W.
Published: August 2022

Massive hemoptysis is a highly morbid medical condition with up to 75% mortality with conservative treatment. Bronchial artery embolization has emerged as the common treatment for both acute massive hemoptysis and chronic hemoptysis. This article will review the clinical presentation, bronchial artery anatomy, embolization procedure, complications, and expected outcomes.
Pleurovenous Shunt Placement for the Management of Nonmalignant Pleural Effusion
Authors: Awwad Andy , Berman Zach , Minocha Jeet
Published: August 2022

Therapeutic thoracentesis is a first-line therapy in the management of patients with medically refractory, nonmalignant pleural effusion. However, when required in short intervals, serial thoracenteses can lead to increased procedure-related complications and negatively impact quality of life. Alternative treatment options vary depending on the etiology of fluid accumulation. Hepatic hydrothorax secondary to cirrhosis is a common cause of medically refractory pleural effusion encountered by interventional radiologists. In select patients in whom surgical pleurodesis, transjugular intrahepatic portosystemic shunt placement, and/or tunneled pleural catheter placement cannot be performed or provide inadequate relief, implantation of a pleurovenous (Denver) shunt may assist in palliation. The Denver shunt system allows decompression of pleural fluid into the central venous circulation by utilizing unidirectional valves and a manually operated subcutaneous pump. Though limited reports have described favorable technical and clinical success, more research is required to determine the safety and efficacy of this procedure. This article discusses pleurovenous shunt placement, postprocedure shunt evaluation, and potential associated complications.
Treating Recurrent Pleural Disease: A Review of Indications and Technique for Chemical Pleurodesis for the Interventional Radiologist
Authors: Trivedi Surbhi B. , Niemeyer Matthew
Published: August 2022

Pleural space diseases such as recurrent pleural effusion and pneumothorax inflict a significant symptomatic burden on patients. Guidelines and studies are available to guide best practices in the setting of refractory effusions, mostly in the setting of malignancy, and recurrent pneumothorax. Less data is available to guide management of refractory transudative effusions. Recurrent pleural effusions can be treated with tunneled pleural catheters or catheter-based pleurodesis. While refractory transudative effusions can benefit from tunneled pleural catheter, this is an area of ongoing research. Regarding recurrent pneumothorax, video-assisted thoracoscopic surgery (VATS) pleurodesis using mechanical or laser/argon beam coagulation is the most effective means of preventing recurrence. Catheter based pleurodesis, a less invasive means of administering chemical sclerosant via percutaneous thoracostomy tube, is only used when surgery is not an option. However, both approaches induce inflammation of the pleural space, resulting in adherence of the parietal and visceral pleura to prevent fluid or air re-accumulation. This article will discuss catheter based chemical pleurodesis geared toward the interventional radiologist, including a review of disease processes and indications, technique, and strategies to mitigate complications as well as a literature review comparing percutaneous chemical pleurodesis to other therapies.
Virtual Surgical Planning in Free Tissue Transfer for Orbito-Maxillary Reconstruction
Authors: Cho Min-Jeong , Hanasono Matthew M.
Published: August 2022

Since its introduction, virtual surgical planning (VSP) has been rapidly adopted as a part of reconstructive surgeon's armamentarium. VSP allows reconstructive surgeons to simulate resection, plan osteotomies, and design custom plates. These unique advantages have been especially beneficial for head and neck reconstructive surgeons as there is small room for error and high technical demand in head and neck reconstruction. Despite its popularity, most surgeons have limited experience in using VSP for orbito-maxillary reconstruction as tumors that involve the midface are relatively rare compared with other head and neck oncologic defects. In our institution, we routinely use VSP for orbito-maxillary reconstruction using free fibula flap to provide support for orbit, to restore normal dental occlusion, and to restore midface projection. In this chapter, we will discuss the role of virtual surgical planning and our algorithmic approach of performing orbito-maxillary reconstruction using free tissue transfer.
Construction and Writing Flaws of the Multiple-Choice Questions in the Published Test Banks of Obstetrics and Gynecology: Adoption, Caution, or Mitigation?
Authors: Balaha Magdy H. , El-Ibiary Mona T. , El-Dorf Ayman A. , El-Shewaikh Shereef L. , Balaha Hossam M.
Published: August 2022

Background The item-writing flaws (IWFs) in multiple-choice questions (MCQs) can affect test validity. The purpose of this study was to explore the IWFs in the published resources, estimate their frequency and pattern, rank, and compare the current study resources, and propose a possible impact for teachers and test writers.

Methods This cross-sectional study was conducted from September 2017 to December 2020. MCQs from the published MCQ books in Obstetrics and Gynecology was the target resources. They were stratified into four clusters (study-book related, review books, self-assessment books, and online-shared test banks). The sample size was estimated and 2,300 out of 11,195 eligible MCQs were randomly selected. The MCQs (items) were judged on a 20-element compiled checklist that is organized under three sections as follows: (1) structural flaws (seven elements), (2) test-wiseness flaws (five elements), and (3) irrelevant difficulty flaws (eight elements). Rating was done dichotomously, 0 = violating and 1 = not violating. Item flaws were recorded and analyzed using the Excel spreadsheets and IBM SPSS.

Results Twenty three percent of the items (n = 537) were free from any violations, whereas 30% (n = 690) contained one violation, and 47% (n = 1073) contained more than one violation. The most commonly reported IWFs were “Options are Not in Order (61%).” The best questions with the least flaws (75th percentiles) were obtained from the self-assessment books followed by study-related MCQ books. The average scores of good-quality items in the cluster of self-assessment books were significantly higher than other book clusters.

Conclusion There were variable presentations and percentages of item violations. Lower quality questions were observed in review-related MCQ books and the online-shared test banks. Using questions from these resources needs a caution or avoidance strategy. Relative higher quality questions were reported for the self-assessment followed by the study-related MCQ books. An adoption strategy may be applied with mitigation if needed.
Enhanced Communication for Interhospital Transfers Increases Preparedness in an Academic Tertiary Care Center
Authors: Leven Emily A. , Luo Yuying , Nguyen Vinh-Tung , Pourmand Kamron
Published: August 2022

Objectives This quality improvement project sought to enhance clinical information sharing for interhospital transfers to an inpatient hepatology service comprised of internal medicine resident frontline providers (housestaff) with the specific aims of making housestaff aware of 100% of incoming transfers and providing timely access to clinical summaries.

Interventions In February 2020, an email notification system to senior medicine residents responsible for patient triage shared planned arrival time for patients pending transfer. In July 2020, a clinical data repository (“Transfer Log”) updated daily by accepting providers (attending physicians and subspecialty fellows) became available to senior medicine residents responsible for triage.

Methods Likert scale surveys were administered to housestaff before email intervention (pre) and after transfer log intervention (post). The time from patient arrival to team assignment (TTA) in the electronic medical record was used as a proxy for time to patient assessment and was measured pre- and postinterventions; >2 hours to TTA was considered an extreme delay.

Results Housestaff reported frequency of access to clinical information as follows: preinterventions 4/31 (13%) sometimes/very often and 27/31 (87%) never/rarely; postinterventions 11/26 (42%) sometimes/very often and 15/26 (58%) never/rarely (p = 0.02). Preinterventions 12/39 (31%) felt “not at all prepared” versus 27/39 (69%) “somewhat” or “adequately”; postinterventions 2/24 (8%) felt “not at all prepared” versus 22/24 (92%) somewhat/adequately prepared (p = 0.06). There was a significant difference in mean TTA between pre- and posttransfer log groups (62 vs. 40 minutes, p = 0.01) and a significant reduction in patients with extreme delays in TTA post-email (18/180 pre-email vs. 7/174 post-email, p = 0.04).

Conclusion Early notification and increased access to clinical information were associated with better sense of preparedness for admitting housestaff, reduction in TTA, and reduced frequency of extreme delays in team assignment.
Photochemical generation of the 2-azabicyclo[4.2.0]octa-4,7-diene skeleton
Authors: Fahrenhorst-Jones Tyler , Savage G. Paul , Williams Craig M.
Published: August 2022

A 2-azabicyclo[4.2.0]octa-4,7-diene derivative was unexpectedly isolated from the photochemical irradiation of 2-vinyl-1,2-dihydropyridine. A cascading 6π–8π–4π electrocyclic rearrangement has been proposed as a possible mechanistic pathway.
Assessment of genetic diversity and DNA fingerprinting of rare species of the genus Crambe (Brassicaceae)
Authors: Chokheli Vasiliy A. , Shmaraeva Antonina N. , Kornienko Igor V. , Stepanenko Victoriya V. , Rajput Vishnu D. , Singh Abhishek , Kumari Arpna , Dmitriev Pavel A. , Azarov Anatoliy S. , Minkina Tatiana M. , Varduni Tatiana V.
Published: August 2022

Context Preservation of genetic diversity of species is a pressing issue; in particular, the preservation of the gene pool of many rare and endangered plants is a priority. Species of the genus Crambe (family Brassicaceae) have potential in agriculture and bioremediation. Aims This study aims to assess the genetic diversity and DNA fingerprint of five rare species of the genus Crambe, and to develop the concept of a genetic passport for rare plants. Methods DNA fingerprinting was conducted via the inter simple sequence repeat (ISSR) method, using six ISSR primers. Hierarchical cluster analysis of the species was performed. Key results In total, 145 polymorphic loci were detected. The studied species formed two different clusters on genetic dendrogram analysis. The first cluster comprised two species, Crambe steveniana and C. tataria from a single subsection (Tatariae), forming a common clade. They were the most genetically close species with genetic similarity of 0.8431. The remaining three species (C. cordifolia, C. maritima, C. pinnatifida), from another subsection of Crambe, formed nodes from the general clade. Conclusions The findings allow plants to be genetically certified using our methods and informative ISSR primers for rare plants. We were able to propose a genetic formula identifying a species and present an example of a genetic passport for rare plants. The genetic structure of C. pinnatifida was investigated for the first time. Implications The present findings contribute to the systematics and critical investigation of rare plant species with genetic resource potential. A genetic passport could be used in the protection of copyright of agricultural varieties.
Nanotechnology for endorsing abiotic stresses: a review on the role of nanoparticles and nanocompositions
Authors: Javed Talha , Shabbir Rubab , Hussain Sadam , Naseer Muhammad Asad , Ejaz Irsa , Ali Muhamamd Moaaz , Ahmar Sunny , Yousef Ahmed Fathy
Published: August 2022

Environmental stresses, including the salt and heavy metals contaminated sites, signify a threat to sustainable crop production. The existence of these stresses has increased in recent years due to human-induced climate change. In view of this, several remediation strategies including nanotechnology have been studied to find more effective approaches for sustaining the environment. Nanoparticles, due to unique physiochemical properties; i.e. high mobility, reactivity, high surface area, and particle morphology, have shown a promising solution to promote sustainable agriculture. Crop plants easily take up nanoparticles, which can penetrate into the cells to play essential roles in growth and metabolic events. In addition, different iron- and carbon-based nanocompositions enhance the removal of metals from the contaminated sites and water; these nanoparticles activate the functional groups that potentially target specific molecules of the metal pollutants to obtain efficient remediation. This review article emphasises the recent advancement in the application of nanotechnology for the remediation of contaminated soils with metal pollutants and mitigating different abiotic stresses. Different implementation barriers are also discussed. Furthermore, we reported the opportunities and research directions to promote sustainable development based on the application of nanotechnology.
Brain-wide functional connectivity of face patch neurons during rest
Authors: Zaldivar Daniel , Koyano Kenji W. , Ye Frank Q. , Godlove David C. , Park Soo Hyun , Russ Brian E. , Bhik-Ghanie Rebecca , Leopold David A.
Published: August 2022

The brain is a highly organized, dynamic system whose network architecture is often assessed through resting functional magnetic resonance imaging (fMRI) functional connectivity. The functional interactions between brain areas, including those observed during rest, are assumed to stem from the collective influence of action potentials carried by long-range neural projections. However, the contribution of individual neurons to brain-wide functional connectivity has not been systematically assessed. Here we developed a method to concurrently measure and compare the spiking activity of local neurons with fMRI signals measured across the brain during rest. We recorded spontaneous activity from neural populations in cortical face patches in the macaque during fMRI scanning sessions. Individual cells exhibited prominent, bilateral coupling with fMRI fluctuations in a restricted set of cortical areas inside and outside the face patch network, partially matching the pattern of known anatomical projections. Within each face patch population, a subset of neurons was positively coupled with the face patch network and another was negatively coupled. The same cells showed inverse correlations with distinct subcortical structures, most notably the lateral geniculate nucleus and brainstem neuromodulatory centers. Corresponding connectivity maps derived from fMRI seeds and local field potentials differed from the single unit maps, particularly in subcortical areas. Together, the results demonstrate that the spiking fluctuations of neurons are selectively coupled with discrete brain regions, with the coupling governed in part by anatomical network connections and in part by indirect neuromodulatory pathways.
Melting temperature prediction using a graph neural network model: From ancient minerals to new materials
Authors: Hong Qi-Jun , Ushakov Sergey V. , van de Walle Axel , Navrotsky Alexandra
Published: August 2022

The melting point is a fundamental property that is time-consuming to measure or compute, thus hindering high-throughput analyses of melting relations and phase diagrams over large sets of candidate compounds. To address this, we build a machine learning model, trained on a database of ∼10,000 compounds, that can predict the melting temperature in a fraction of a second. The model, made publicly available online, features graph neural network and residual neural network architectures. We demonstrate the model’s usefulness in diverse applications. For the purpose of materials design and discovery, we show that it can quickly discover novel multicomponent materials with high melting points. These predictions are confirmed by density functional theory calculations and experimentally validated. In an application to planetary science and geology, we employ the model to analyze the melting temperatures of ∼4,800 minerals to uncover correlations relevant to the study of mineral evolution.
Entangling two cavity modes and squeezing magnon mode via parametric down-conversion
Authors: Zhou Ying , Xu Jingping , Xie Shuangyuan
Published: August 2022

A scheme to entangle two cavity modes and squeeze magnon mode in a magnon–cavity QED system is presented, where the two microwave cavity modes are coupled to a massive yttrium iron garnet sphere. The nonlinearity used in our system originates from parametric down-conversion. By using the mean field approximation and employing experimentally feasible parameters, we indicate that the entanglement between squeezed cavity mode and magnon mode can be transferred to the other cavity mode and magnon mode, and then the two cavity modes get entangled. Meanwhile, the magnon mode is squeezed in our QED system. Furthermore, we show that it is a good way to enhance entanglement and squeezing by increasing the nonlinear gain. Our results denote that magnon–cavity QED system is a powerful platform for studying macroscopic quantum phenomena, which illustrates a new approach to photon–photon entanglement and magnon squeezing.
Ground experiment verification and on-orbit prediction of the two-stage cooling at pK level in the Chinese space station
Authors: Xie Yu , Fan Bo , Li Hui , Liang Angang , Huang Mingshan , Wu Biao , Wang Bin , Chen Xuzong , Liu Liang
Published: August 2022

In order to infer the expected temperature of the two-stage cooling experiment onboard the Chinese space station (CSS) through ground experiments, we apply the direct simulation Monte Carlo algorithm to construct a simulation model suitable for both the standard gravity and the microgravity conditions. The simulations are verified by the ground experimental results, from which we can deduce that the on-orbit experiments can reach the order of as low as 100 pK. This algorithm calculates the corresponding relationship between the temperature in the ground experiments and that in the microgravity conditions, keeping the other experimental parameters unchanged, which provides an important basis of design for the on-orbit atomic cooling experiment onboard the CSS which is due to be launched at the end of 2022.
Surface-standing-wave formation via resonance interaction of a finite-length conductive rod with microwaves
Authors: Abrahamyan Tigran , Haroyan Hovhannes , Hambaryan David , Parsamyan Henrik , Babajanyan Arsen , Lee Kiejin , Friedman Barry , Nerkararyan Khachatur
Published: August 2022

The resonant response of a thin conducting rod with a finite length irradiated by microwaves polarized along its axis is observed. By using a thermoelastic optical indicator microscope it is shown that rod with a length of several half- wavelengths can serve as a resonator for axial surface waves. It is facilitated by noticeable reflections (approximately 30%) from the rod edges conditioned by the unique distributions of Sommerfeld wave fields along a rod. The presence of a weak axial electric field component of surface waves ensures an easy coupling with the incident plane wave polarized along the rod axis and excites the resonator. Visualization of distributions of the near-field magnetic component of surface standing waves in the vicinity of a rod allows the exploration of three longitudinal modes of a resonator with low orders. The possibility of controlling the resonant frequency by changing the length and diameter of the rod, as well as the electromagnetic characteristics of the environment, are studied. The phenomenon under study can be used to create wavefront shaping metasurfaces and for studies of the properties of a dielectric medium in the microwave region. As Sommerfeld waves propagate on the surface of a cylindrical resonator, the resonant properties are sensitive to the dielectric permittivity of the surrounding medium, which will open up the potential for using the suggested resonator in sensing applications, which is experimentally demonstrated.
Rapid thermal vapor condensation towards crystalline carbon nitride film with improved photoelectrochemical activity
Authors: Oo May Thawda , Tian Haoran , Zhao Yanling , Zhang Rui-Qin
Published: August 2022

Graphitic carbon nitride (g-CN), as an orderly structured polymer derivative, has been widely concerned for its photocatalytic ability due to its metal-free nature and unique properties. However, the photoelectrochemical (PEC) application of g-CN is still hindered by the difficulty of forming high-quality films with good uniformity and crystallinity. Herein, we studied the rapid thermal vapor condensation (RTVC) for growing g-CN films with improved PEC activity. The polycondensation and polymerization reactions of precursor melamine molecules under the optimized temperature 600 °C and calcination time 20 min resulted in better crystallinity of g-CN films. Remarkably, the growth of g-CN film based on the coalescence of unambiguous hexagonal nanosheets was observed, as corroborated by scanning electron microscopy and transmission electron microscopy. This novel RTVC method offers a fast and easy strategy for improving the crystallinity of g-CN films through controlling the thermal dynamics and kinetics of film growth from temperature and time.
High detectivity graphene/si heterostructure photodetector with a single hydrogenated graphene atomic interlayer for passivation and carrier tunneling
Authors: Cong Jingkun , Khan Afzal , Hang Pengjie , Cheng Li , Yang Deren , Yu Xuegong
Published: August 2022

Hydrogenated graphene is easy to prepare and chemically stable. Besides, hydrogenation of graphene can open the band gap, which is vital for electronic and optoelectronic applications. Graphene/Si photodetector (PD) has been widely studied in imaging, telecommunications, and other fields. The direct contact between graphene and Si can form a Schottky junction. However, it suffers from poor interface state, where the carrier recombination at the interface causes serious leakage current, which in turn leads to a decrease in the detectivity. Hence, in this study, hydrogenated graphene is used as an interfacial layer, which passivates the interface of graphene/Si (Gr/Si) heterostructure. Besides, the single atomic layer thickness of hydrogenated graphene is also crucial for the tunneling transport of charge carriers and its suitable energy band position reduces the recombination of carrier. The fabricated graphene/hydrogenated-graphene/Si (Gr/H–Gr/Si) heterostructure PD showed an extremely low dark current about 10−7 A. As a result, it had low noise current and exhibited a high specific detectivity of ∼2.3 × 1011 Jones at 0 V bias with 532 nm laser illumination. Moreover, the responsivity of the fabricated PD was found to be 0.245 A W−1 at 532 nm illumination with 10 μW power. These promising results show a great potential of hydrogenated graphene to be used as an interface passivation and carrier tunneling layer for the fabrication of high-performance Gr/Si heterostructure PDs.
Mechanisms of self-organization of a microwave streamer leading to maximum energy absorption
Authors: Brovkin V G , Vedenin P V
Published: August 2022

An attempt is made to reveal the general principle of the formation of a thin microwave plasma channel (filament) in free space. The channel is the main element of dipole-type plasma structures developing at high pressure in a beam (or beams) of electromagnetic waves away from surfaces. The mechanisms of self-organization of the thin plasma filament at various stages of its evolution are revealed. The triggering of these mechanisms leads to the fact that the total absorbed energy (Joule’s losses) at each moment of time is close to its upper estimate. The reaction of the electric field-plasma channel system to the change in the rate constants of the main processes of production and loss of electrons in air at the most energy-intensive stage has been studied. The maximum energy absorption is provided by rate constants that are in good agreement with currently used constants.
Synchronous chip-to-chip communication with a multi-chip resonator clock distribution network
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Authors: Egan Jonathan , Nielsen Max , Strong Joshua , Talanov Vladimir , Rudman Ed , Song Brainton , Herr Quentin , Herr Anna
Published: August 2022

Superconducting digital circuits are a promising approach to build integrated systems with high energy-efficiency and computational density of the packaged chips. In such systems, performance of the data link between chips mounted on a multi-chip-module (MCM) is a critical driver of performance. In this work we report a synchronous data link using reciprocal quantum logic enabled by resonant clock distribution on-chip and on the MCM carrier. The simple physical link has only four Josephson junctions and 3 fJ/bit dissipation, including a 300 W/W cooling overhead. The driver produces a signal with 35 GHz analog bandwidth and connects to a single-ended receiver via 20 Ω Nb passive transmission line. To validate this link, we have designed, fabricated, and tested two 32 × 32 mm2 MCMs with eight 5 × 5 mm2 chips connected serially and powered by a traveling-wave clock, and with four 10 × 10 mm2 chips powered with a 2 GHz resonant clock. The traveling-wave clock MCM validates performance of the data link components and achieves a 5.4 dB AC bias margin with no degradation relative to individual chip tests. The resonator MCM validates synchronization between chips, with a measured AC bias margin up to 4.8 dB between two chips. The resonator MCM is capable of powering circuits of 4 million Josephson junctions across the four chips with a projected 10 Gbps serial data rate.
Differential geometry method for minimum hard-way bending 3D design of coils with ReBCO tape conductor
Authors: Nes T H , de Rijk G , Kario A , ten Kate H H J
Published: August 2022

The use of tape conductor poses design challenges for superconducting magnets. Due to its very high aspect ratio, it is hardly possible to bend the conductor over its thin edges (hard-way bending) rather than over its wide side (easy-way bending). Overstraining the conductor causes critical current degradation. In this paper, we propose a new design approach to three-dimensional coil layouts and coil end geometries with tape conductor, which considers the tape’s geometrical limitations. To geometrically describe the conductor surface, we use the thin strip model, also referred to as constant perimeter geometry. To prevent conductor degradation, new optimization criteria valid for three-dimensional geometries are presented, which are prevention of conductor creasing, minimization of overall bending energy, and prevention of over-straining the conductor. We will apply this to two 3D coil designs called helix and canted cosine theta. For the design of the coil ends, we propose a new design method using Bézier splines, which allows for much greater design flexibility than previous methods. Two examples of coil end geometries generated with Bézier splines are presented: the so-called cloverleaf and cosine-theta.
Broadband and high-numerical-aperture sharp focusing for waterborne sound with metagrating-based lens
Authors: Mei Jun , Fan Lijuan , Hong Xiaobin
Published: August 2022

Metalens with broadband and high-efficiency focusing functionality is desired in various underwater acoustic applications such as sonar and oceanography. Here we design and demonstrate a metagrating-based lens consisting of spatially sparse and wavelength-scale meta-atoms with optimized structures. With the help of grating diffraction analysis and intelligent optimization algorithm, the reflective metalens enables broadband and high-numerical-aperture focusing for waterborne sound over a 40 kHz-bandwidth for working frequency at 200 kHz. Full-wave numerical simulations unambiguously verify a sharp and high-efficiency focusing of sound wave intensity, with the full width at half maximum at the focal spot being smaller than 0.5λ and thus beating the Rayleigh–Abbe diffraction limit. Our work not only provides an intelligent design paradigm of high-performance metalens, but also presents a potential solution for the development of planar acoustic devices for high-resolution applications.