bluuebunny/crossref_metadata_2025 huggingface dataset:
Regionale Hospiz- und Palliativnetzwerke in Niedersachsen: Ergebnisse einer Online-Bestandserhebung und -analyse
Authors: Schwabe Sven , Fischer Rosemarie , Herbst Franziska A. , Schleef Tanja , Schneider Nils
Published: July 2022

Ziel der Studie Der Bestand von regionalen Hospiz- und Palliativnetzwerken (RHPN) in Niedersachsen soll erstmals exploriert und analysiert werden.

Methodik Im Februar 2022 wurde via SoSciSurvey eine Online-Befragung von RHPN in Niedersachsen durchgeführt. Inhalt der Befragung waren: a) Netzwerkorganisation und -struktur, b) Themen und Tätigkeitsfelder, c) Herausforderungen und Unterstützungsbedarfe. Der Befragungslink wurde an alle registrierten Palliativstützpunkte (n=33) und SAPV-Teams (n=43) in Niedersachsen versendet. Die Daten wurden deskriptiv in Microsoft Excel 2016 ausgewertet.

Ergebnisse Insgesamt haben 34 RHPN aus 33 Landkreisen und Städten teilgenommen, wovon 29 Träger eines SAPV-Teams waren. Häufigste Inhalte der Netzwerkarbeit sind die Themen SAPV (n=32), ambulante Hospizarbeit (n=22) und die Versorgung in Pflegeeinrichtungen (n=22).

Schlussfolgerung RHPN in Niedersachsen sind vielfältig und eng mit den ambulanten Strukturen der Hospizarbeit und der SAPV verbunden.
Recent Progress in C(sp2)–C(sp2) Bond Formation Using Ligand Coupling on Sulfur(IV)
Authors: Morofuji Tatsuya , Kano Naokazu
Published: July 2022

Ligand coupling on sulfur, as an alternative to transition-metal-catalyzed cross-coupling reactions, is a useful method for connecting sp2 carbons. Although pioneered more than 50 years ago, its synthetic utility has been overlooked until recently. This short review summarizes progress in C(sp2)–C(sp2) bond formation using ligand coupling on sulfur and discusses control of selectivity, expansion of the scope, and applications of the reaction.

1 Introduction

2 Cross-Coupling of Heteroaryl Reagents

3 Phenothiazinium-Mediated C(sp2)–C(sp2) Cross-Coupling

4 C(sp2)–C(sp2) Bond Formation Mediated by Sulfuranes Generated from Arynes and Sulfoxides

5 S-Alkenylbenzothiophenium-Mediated Alkenyl-Alkenyl Coupling

6 Conclusion
Recent Advances in Transition-Metal-Catalyzed Cross-Coupling Reactions of gem-Difluorinated Cyclopropanes
Authors: Xia Ying , Zhu Yulei , Zeng Yaxin , Jiang Zhong-Tao
Published: July 2022

As a special class of cyclopropanes, gem-difluorinated cyclopropanes have many fascinating properties as a result of the gem-difluoro substitution; thus, their reactions have received much attention from the synthetic chemistry community. Recently, gem-difluorinated cyclopropanes have gradually emerged as a type of novel and unique fluorinated allylic synthon in cross-coupling reactions for the synthesis of monofluoroalkenes. Herein, we briefly summarize recent advances in transition-metal-catalyzed reactions of gem-difluorinated cyclopropanes.

1 Introduction

2 Palladium-Catalyzed Reactions with Linear Selectivity

3 Palladium-Catalyzed Reactions with Branched Selectivity

4 Other Metal-Catalyzed Reactions

5 Conclusions
Catalytic Enantioselective Desymmetrization of meso-Cyclopropane-Fused Cyclohexene-1,4-diones by a Formal C(sp2)–H Alkylation
Authors: Mukherjee Santanu , Ray Sayan
Published: July 2022

A bicyclo[4.1.0]heptane framework consisting of cis-fused cyclopropane and cyclohexane rings is found in several bioactive compounds. Given the symmetry of this core, catalytic desymmetrization can be considered as the most straightforward strategy for its enantioselective synthesis. Known desymmetrization reactions of meso-bicyclo[4.1.0]heptane derivatives proceed with opening of the cyclopropane ring. We now report the first ring-retentive desymmetrization of bicyclo[4.1.0]heptane derivatives, namely meso-cyclopropane-fused cyclohexene-1,4-diones, through a formal C(sp2)-H alkylation using a nitroalkane as the alkylating agent. This reaction is catalyzed by a dihydroquinine-derived bifunctional tertiary aminosquaramide and generates the products with up to 97:3 er. An application of this reaction is demonstrated by the first catalytic enantioselective synthesis of the natural product (–)-car-3-ene-2,5-dione.
Boron Trifluoride Etherate-Controlled Reactions of Methyl Enol Ethers: Selective Synthesis of Dihydrofuro[3,2-c]chromenone and Furo[3,2-c]chromenone Derivatives
Authors: Khan Faiz Ahmed , Ahmad Sarwat Asma Ziya
Published: July 2022

A facile one-step synthetic approach to dihydrofuro-[3,2-c]chromenones and furo[3,2-c]chromenones by the reaction of methyl enol ethers with 4-hydroxycoumarins under metal-free conditions is presented. Dihydrofuro[3,2-c]chromenones and furo[3,2-c]-chromenones were selectively obtained by controlling the stoichiometry of boron trifluoride diethyl etherate. An unexpected aryl-group migration followed by aromatization of the furan moiety, leading to a variety of furo[3,2-c]chromenone derivatives in good yields, is reported.
Percutaneous Cannulation of Femoral Vessels in Minimally Invasive Cardiac Surgery
Authors: Sugimura Yukiharu , Jandali Hassan , Immohr Moritz Benjamin , Katahira Shintaro , Minol Jan-Philipp , Lichtenberg Artur , Akhyari Payam
Published: July 2022

Objective Despite the recent trend of access miniaturization in minimally invasive cardiac surgery (MICS) surgical “cut down (CD)” for femoral cannulation remains the standard at many centers. Percutaneous vascular closure (PVC) devices have recently been introduced for minimizing invasiveness during interventional diagnostic and therapy. This report summarizes the initial experience with this new approach in the setting of MICS, with a special focus on safety and advantages.

Methods Percutaneous cannulation with a standard protocol including preoperative computer tomography imaging and intraoperative point-of-care ultrasound guidance was performed in 93 consecutive patients from September 2018 until February 2020, while conventional “CD” procedure performed in 218 patients in the previous period. We analyzed patients' characteristics and compared access site complications of PVC group versus conventional “CD” group.

Results As far as operative/postoperative outcome, the duration of intensive care unit stay as well as hospital stay was statistically shorter in PVC compared with CD (CD vs. PVC: 2.74 ± 3.83 vs. 2.16 ± 2.01 days, p < 0.01, 16.7 ± 8.75 vs. 13.0 ± 4.96 days, p < 0.001, respectively). Further, we found no femoral infection or lymphocele in the PVC group, whereas 4 cases of wound complications were observed in the CD group.

Conclusion According to our results, percutaneous closure system for femoral vessels in MICS seems to be beneficial with the assist of preoperative computed tomography and intraoperative Doppler guidance.
Impact of COVID-19 on the Ophthalmology Residency Home-Institution Match Rate
Authors: Swan Robert T. , Syed Misha F. , Crowder Kimberly W. , Lee Andrew G.
Published: July 2022

Purpose The aim of this study was to evaluate the ophthalmology residency match results to determine changes in the rate of home-institution matches during the coronavirus disease 2019 (COVID-19) pandemic.

Methods Aggregate deidentified summary match result data from 2017 to 2022 was obtained from the Association of University Professors of Ophthalmology and the San Francisco (SF) Match. A chi-squared test was performed to determine if the rate of candidate matching to the home residency program in ophthalmology was higher in the post-COVID-19 compared with pre-COVID-19 match years. A literature review using PubMed was performed of other medical subspecialty match rates to home institution during the same study period.

Results A chi-squared test for difference in proportions confirmed a significantly higher chance of matching to the home program for ophthalmology in the post-COVID-19, SF Match year of 2021 to 2022 compared with 2017 to 2020 (p = 0.001). Other medical specialties including otolaryngology, plastic surgery, and dermatology also showed similar increased home institution residency match rates during the same time period. Although neurosurgery and urology also had increased trend rates for home institution match rates, these results did not reach statistical significance.

Conclusions The ophthalmology home-institution residency SF Match rate was significantly increased during the COVID-19 pandemic year 2021 to 22. This mirrors a trend reported in other specialties including the otolaryngology, dermatology, and plastic surgery in the 2021 match. Additional study will be required to identify factors leading to this observation.
Perioperative Clinical Features of Mediastinal Parathyroid Adenoma: A Case Series
Authors: Wang Fuqiang , Zhang Hanlu , Qiu Guanghao , Wang Yun
Published: July 2022

Rare ectopic mediastinal parathyroid adenoma can result in persistent or recurrent hyperparathyroidism. In this article, we summarized the perioperative outcomes of six patients with mediastinal parathyroid adenoma. All patients underwent minimally invasive surgery (MIS). Abnormal accumulation of sestamibi was observed in four of five patients for preoperative localization of adenoma. Postoperatively, the blood calcium dropped quickly. In addition, we found adenoma function was negatively related to adenoma volume in these patients. In conclusion, although MIS is feasible for parathyroid adenoma, blood calcium should be monitored in a timely manner to avoid hypocalcemia postoperatively. In addition, sestamibi might be a potential pitfall when locating parathyroid adenoma.
The German Cardiosurgery Atrial Fibrillation Registry: 1-Year Follow-up Outcomes
Authors: Wehbe Mahmoud , Albert Marc , Lewalter Thorsten , Ouarrak Taoufik , Senges Jochen , Hanke Thorsten , Doll Nicolas
Published: July 2022

Objectives This study of German Cardiosurgery Atrial Fibrillation (CASE-AF) registry aims to describe the 1-year outcomes of patients undergoing ablative procedures for atrial fibrillation (AF) in a cardiosurgical setting.

Methods Between January 2017 and April 2020, 17 German cardiosurgical units enrolled 1,000 consecutive patients undergoing concomitant or stand-alone ablation for AF. In-hospital and 1-year follow-up data were collected on web-based electronic case report forms. The protocol mandated telephone-based follow-up contact after 1 year.

Results At 1-year follow-up (median, 14.5 months [12.6–18.2 months]), significant improvement (p < 0.0001) in baseline modified European Heart Rhythm Association Class I was reported in both concomitant and stand-alone patients. Follow-up examinations were completed in 97.9% of cases, and a sinus rhythm was reported in 60.2 and 63.6% of stand-alone and concomitant patients, respectively. Statistically significant factors determining late recurrence were female gender (p = 0.013), preoperative persistent AF (p < 0.0001), and presence of cardiac implantable electronic device (p = 0.011). All-cause mortality at 1 year was 1% (n = 1) in stand-alone patients and 6.7% (n = 58) in concomitant patients.

Conclusion Surgical ablation of AF is safe and provides satisfactory results at short-term follow-up, with significant improvement in patient symptoms. Adequate cardiac rhythm monitoring should be prioritized for higher quality data acquisition.
Atrial Fibrillation after Coronary Bypass Surgery? Is Epicardial Fat a Risk Factor?
Authors: Yalçınkaya Adnan , Fidan Nurdan , Sarı Engin , Özyalçın Sertan , Diken Adem İlkay
Published: July 2022

Backgrounds Postoperative atrial fibrillation (POAF) is one of the most common complication of cardiac surgery. Epicardial fat tissue may play a role in the development of atrial fibrillation (AF). The aim of this study was to evaluate relationship between epicardial fat volume (EFV) and the appearance of new-onset AF in patients undergoing isolated coronary artery bypass graft (CABG) with normal echocardiographic functions.

Methods Between January 2017 and June 2020, 281 coronary artery disease patients undergone isolated CABG surgery with normal echocardiographic functions were included in the study. Patient characteristics, medical history, and perioperative variables were retrospectively collected. Patients with AF predisposition factors were excluded.

Results Sixty-seven patients (23.8%) developed postoperatively AF during hospital stay. In univariate analysis, patients with postoperative AF were older compared with sinus rhythm patients (60.78 ± 9.03 vs. 65.46 ± 9.22, p = 0.001). There are no statistically significant differences between groups and EFV compared (107.78 ± 41.04 vs. 106.66 ± 34.98 p = 0.84). Large left atrial diameter, female patient, cardiopulmonary bypass and longer cross-clamp time showed correlation between POAF without statistical significance.

Conclusion Aging is the only associated factor with AF in this study. There was no EFV difference between POAF and non-AF groups in patients undergoing isolated CABG with normal echocardiographic functions.
A Review of the Nature and Development of Humor Appreciation and Considerations for Teaching Humor to Autistic Persons
Authors: Hutchins Tiffany L.
Published: July 2022

The development of humor is complex and heterogeneous within and across neurotypical and neurodivergent groups. Some autistics develop differences (not deficits) in humor appreciation, whereas others report difficulties “getting the joke” and identify this as in need of support. This is important because humor appreciation and comprehension are linked to psychological well-being and social success. This article describes the therapeutic potential for teaching humor comprehension to autistic persons and the benefit of broader education efforts to forge an understanding of the value of “different senses of humor.” The nature and development of humor comprehension in neurotypical development and autism are reviewed. Considerations for whether and how to teach humor comprehension are offered that maximize goodness-of-fit, prioritize autistic autonomy, and promote the sharing and appreciation of different kinds of “funny.”
Outcomes of Pediatric Drowning in the Pediatric Intensive Care Unit
Authors: Aures Rebecca K. , Rosenthal Jennifer , Chandler Ashley , Raybould Toby , Flaherty Michael R.
Published: July 2022

Drowning remains a leading cause of death in children. Knowledge of outcomes of these patients who survive drowning but require critical care is lacking. We aim to study the current mortality rate, describe interventions and associated diagnoses, and examine factors related to risk of death in drowning victims admitted to the pediatric intensive care unit (PICU). We conducted a retrospective multicenter cohort study utilizing data from the Virtual Pediatric Systems Database in 143 PICUs between January 1, 2010, and December 31, 2019. Patients between 0 and 18 years of age admitted to a PICU with a diagnosis of drowning were included. The primary outcome was death prior to hospital discharge. Predictors included demographics, critical care interventions, and associated diagnoses. Odds ratios were calculated using multivariate logistic regression. There were 4,855 patients admitted with drowning across the study period. The overall PICU mortality rate in this cohort was 18.7%. Factors associated with an increased odds of death included being transported from an outside hospital, mechanical ventilation, central line placement, cardiac arrest, respiratory failure, and hypoxic ischemic encephalopathy. In 2,479 patients requiring mechanical ventilation, 63 were treated with extracorporeal membrane oxygenation which was not associated with mortality. This data provide updated insight into pediatric drowning victims requiring critical care and their prognosis, as it relates to the interventions they receive. Overall PICU mortality rates for drowning are higher than overall PICU mortality and mortality from other causes of injury. These findings have implications for the care of drowned children in ICU environments and in continued preventive efforts.
Potential Mechanisms of Yanghe Decoction in the Treatment of Soft Tissue Sarcoma and Arteriosclerosis Obliterans Based on Network Pharmacology
Authors: Zhai Yiran , Jiang Shiqing , Li Binyi , Miao Lili , Wang Jie , Li Shanshan
Published: July 2022

Objective The objective of this study was to investigate potential mechanisms of Yanghe Decoction (

, YHD) in treating soft tissue sarcoma (STS) and arteriosclerosis obliterans (ASO) based on the use of network pharmacology.

Methods Candidate compounds and potential targets were identified through the TCM Systems Pharmacology database and a comprehensive literature search. Related targets of STS and ASO were collected in the GeneCards database, DisGeNET database, and Drugbank database. Furthermore, The STRING 11.0 database was used to determine protein–protein interaction (PPI) networks; common targets were obtained and imported into Cytoscape 3.7.2. Then, a PPI network comprising common targets was drawn, and network topology analysis was performed to screen for key shared targets. Gene ontology functional enrichment analysis and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis of key shared targets were performed by using Metascape software. Subsequently, a compound–target–pathway network was constructed via Cytoscape 3.7.2.

Results The following signaling pathways were found to be associated with the mechanisms of YHD in treating STS and ASO: AGE-RAGE signaling pathway, IL-17 signaling pathway; HIF-1 signaling pathway, TNF signaling pathway, interactions between cytokines and cytokine receptors, Th17 cell differentiation, and NOD-like receptor signaling pathway. Among the compounds and targets involved in these pathways, quercetin, luteolin, and kaempferol were found to be core compounds, and TNF, IL-6, and MAPK1 were found to be core targets.

Conclusion Taken together, our findings elucidated that potential mechanisms of YHD in treating STS and ASO involved cellular proliferation/differentiation, angiogenesis, inflammation, immune responses, oxidative stress, and other related signaling pathways.
COVID-19 Effects on Public Finance and SDG Priorities in Developing Countries: Comparative Evidence from Bangladesh and Sri Lanka
Authors: Colombage Sisira R. N. , Barua Suborna , Nanayakkara Madurika , Colombage Udari N.
Published: July 2022

The COVID-19 pandemic, an unprecedented global health crisis, rapidly transferred into a global economic and social crisis. The pandemic has threatened the world’s commitment to achieve Sustainable Development Goals (SDGs) by 2030 as governments in developing countries have shifted their priorities from attaining SDGs, to providing urgent financial needs to save lives and prevent recession in hopes for a rapid economic recovery. The rerouting of public funding priorities has undermined the progress and achievement of SDGs. We employed a mixed-method and carried out a comparative study using pre- and post-public financial data of two developing countries in South Asia; Bangladesh and Sri Lanka. A threefold analysis was conducted to investigate the evolution of the COVID-19 pandemic in two countries, the impact of the pandemic on external and internal public finance and the effect of the pandemic in shifting the policy priorities from SDGs to economic survival. This study found that both countries are highly vulnerable to the COVID-19 pandemic and are suffering from the lack of financing from external sources through the private sector as well as an increasing foreign debt. There is mounting pressure on the fiscal balance in both countries.
Magneto-transport properties of Si1−xGex  whiskers
Authors: Druzhinin Anatoly , Ostrovskii Igor , Khoverko Yuriy , Liakh-Kaguy Natalia
Published: July 2022

The field and temperature magnetoresistance dependences of the Si1−xGex (x = 0.05) whiskers at low temperatures were studied in the magnetic field range of 0−14 T with using of the Bitter magnet. The investigated whiskers with diameters 5−15 μm were grown by chemical vapour deposition with a doping concentration in the vicinity to the metal-insulator transition (Nc ≈ 7.8 ⋅ 1018 cm−3). The linear magnetoresistance effect of the solid solution Si1-xGex  whiskers was found in all range of the magnetic fields due to the surface coherence scattering of charge carriers as a result of conduction in the whisker core-shell structure.
Role of magnons and the size effect in heat transport through an insulating ferromagnet taking into account the magnetic field
Authors: Shklovskij V. A. , Naboichenko O. S.
Published: July 2022

We solve a kinetic, space-dependent problem in an insulator/ferromagnet/insulator heterostructure in the presence of a magnetic field. At the same time, to interpret experiments on thermal transfer across ferromagnet / insulator boundaries, the Little acoustic mismatch theory is usually used, in which the temperature jump at the interface is determined only by the acoustic characteristics of the medium. We show that the theory of acoustic mismatch is convenient only for sufficiently thick insulating ferromagnets. Of the greatest interest to us is the opposite limiting case of thin ferrodielectric films, where the role of magnons in the formation of a temperature jump at the ferromagnet/insulator interface becomes decisive. We show that for T ≪ ΘD a nonlinear heat flux Q crossing the ferrodielectric/insulator interface, both the size effect and its decreasing dependence on the external magnetic field increase. Namely, Q depends on the magnetic properties of thin heated ferromagnetic films, and the role of magnons is essential in the heat transfer regime, which we call magnon overheating. On the contrary, for thick heated layers of a ferromagnet, Q can be described by the Little formula, which does not take into account the magnetic properties of the ferromagnet layer.
Hydrogen bond arrangements in (H2O)20, 24, 28 clathrate hydrate cages: Optimization and many-body analysis
Authors: Heindel Joseph P. , Kirov Mikhail V. , Xantheas Sotiris S.
Published: July 2022

We provide a detailed study of hydrogen bonding arrangements, relative stability, residual entropy, and an analysis of the many-body effects in the (H2O)20 (D-cage), (H2O)24 (T-cage), and (H2O)28 (H-cage) hollow cages making up structures I (sI) and II (sII) of clathrate hydrate lattices. Based on the enumeration of the possible hydrogen bonding networks for a fixed oxygen atom scaffold, the residual entropy (S0) of these three gas phase cages was estimated at 0.754 82, 0.754 44, and 0.754 17 · Nkb, where N is the number of molecules and kb is Boltzmann’s constant. A previously identified descriptor of enhanced stability based on the relative arrangement and connectivity of nearest-neighbor fragments on the polyhedral water cluster [strong-weak-effective-bond model] also applies to the larger hollow cages. The three cages contain a maximum of 7, 9, and 11 such preferable arrangements of trans nearest dimer pairs with one “free” OH bond on the donor molecule (t1d dimers). The Many-Body Expansion (MBE) up to the 4-body suggests that the many-body terms vary nearly linearly with the cluster binding energy. Using a hierarchical approach of screening the relative stability of networks starting from optimizations with the TIP4P, TTM2.1-F, and MB-pol classical potentials, subsequently refining at more accurate levels of electronic structure theory (DFT and MP2), and finally correcting for zero-point energy, we were able to identify a group of four low-lying isomers of the (H2O)24 T-cage, two of which are antisymmetric and the other two form a pair of antipode configurations.
On-chip selection of adenosine aptamer using graphene oxide-coated magnetic nanoparticles
Authors: Lim Hosub , Chang Junhyuck , Kim Kyung-il , Moon Youngkwang , Lee Saebom , Lee Byoungsang , Lee Jung Heon , Lee Jinkee
Published: July 2022

Systematic evolution of ligands by exponential enrichment (SELEX) is a method that is generally used for developing aptamers, which have arisen the promising alternatives for antibodies. However, conventional SELEX methods have limitations, such as a limited selection of target molecules, time-consuming and complex fabrication processes, and labor-intensive processes, which result in low selection yields. Here, we used (i) graphene oxide (GO)-coated magnetic nanoparticles in the selection process for separation and label-free detection and (ii) a multilayered microfluidic device manufactured using a three-dimensionally printed mold that is equipped with automated control valves to achieve precise fluid flows. The developed on-chip aptamer selection device and GO-coated magnetic nanoparticles were used to screen aptamer candidates for adenosine in eight cycles of the selection process within approximately 2 h for each cycle. Based on results from isothermal titration calorimetry, an aptamer with a dissociation constant of 18.6 ± 1.5 μM was selected. Therefore, the on-chip platform based on GO-coated magnetic nanoparticles provides a novel label-free screening technology for biosensors and micro/nanobiotechnology for achieving high-quality aptamers.
Numerical study of electric plume in viscoelastic fluids within a blade-plate structure
Authors: Su Zheng-Gang , Zhang Zi-Yao , Ma Xiao , Luo Kang , Yi Hong-Liang
Published: July 2022

A two-dimensional numerical study on the behavior of electric plumes in viscoelastic fluids within a blade-plate structure is conducted herein. The Oldroyd-B constitutive equation is used to model the viscoelastic fluid. The effects of elasticity on the development processes of electric plumes and the heat transfer characteristics are mainly investigated. Moreover, the flow structure of the electric plume with self-similar characteristics which is similar to the thermal plume has been successfully characterized using the evolution of the charge distribution. Additionally, the results show that the elastic effect can promote electric plume development. The stronger the elastic effect is, the faster the electric plume rises. Furthermore, the influence of other dimensionless parameters on the electric plume is analyzed. When considering the impingement cooling effect of the electric plume, the elastic effect inhibits the heat transfer of the system after the plume fully develops.
Effect of obstructions on growing Turing patterns
Authors: Dolnik Milos , Konow Christopher , Somberg Noah H. , Epstein Irving R.
Published: July 2022

We study how Turing pattern formation on a growing domain is affected by discrete domain discontinuities. We use the Lengyel–Epstein reaction–diffusion model to numerically simulate Turing pattern formation on radially expanding circular domains containing a variety of obstruction geometries, including obstructions spanning the length of the domain, such as walls and slits, and local obstructions, such as small blocks. The pattern formation is significantly affected by the obstructions, leading to novel pattern morphologies. We show that obstructions can induce growth mode switching and disrupt local pattern formation and that these effects depend on the shape and placement of the objects as well as the domain growth rate. This work provides a customizable framework to perform numerical simulations on different types of obstructions and other heterogeneous domains, which may guide future numerical and experimental studies. These results may also provide new insights into biological pattern growth and formation, especially in non-idealized domains containing noise or discontinuities.
DRLinFluids: An open-source Python platform of coupling deep reinforcement learning and OpenFOAM
Authors: Wang Qiulei , Yan Lei , Hu Gang , Li Chao , Xiao Yiqing , Xiong Hao , Rabault Jean , Noack Bernd R.
Published: July 2022

We propose an open-source Python platform for applications of deep reinforcement learning (DRL) in fluid mechanics. DRL has been widely used in optimizing decision making in nonlinear and high-dimensional problems. Here, an agent maximizes a cumulative reward by learning a feedback policy by acting in an environment. In control theory terms, the cumulative reward would correspond to the cost function, the agent to the actuator, the environment to the measured signals, and the learned policy to the feedback law. Thus, DRL assumes an interactive environment or, equivalently, a control plant. The setup of a numerical simulation plant with DRL is challenging and time-consuming. In this work, a novel Python platform, namely DRLinFluids, is developed for this purpose, with DRL for flow control and optimization problems in fluid mechanics. The simulations employ OpenFOAM as a popular, flexible Navier–Stokes solver in industry and academia, and Tensorforce or Tianshou as widely used versatile DRL packages. The reliability and efficiency of DRLinFluids are demonstrated for two wake stabilization benchmark problems. DRLinFluids significantly reduces the application effort of DRL in fluid mechanics, and it is expected to greatly accelerate academic and industrial applications.
Adsorption free energy predicts amyloid protein nucleation rates
Authors: Toprakcioglu Zenon , Kamada Ayaka , Michaels Thomas C. T. , Xie Mengqi , Krausser Johannes , Wei Jiapeng , Saric Andela , Vendruscolo Michele , Knowles Tuomas P. J.
Published: July 2022

Primary nucleation is the fundamental event that initiates the conversion of proteins from their normal physiological forms into pathological amyloid aggregates associated with the onset and development of disorders including systemic amyloidosis, as well as the neurodegenerative conditions Alzheimer’s and Parkinson’s diseases. It has become apparent that the presence of surfaces can dramatically modulate nucleation. However, the underlying physicochemical parameters governing this process have been challenging to elucidate, with interfaces in some cases having been found to accelerate aggregation, while in others they can inhibit the kinetics of this process. Here we show through kinetic analysis that for three different fibril-forming proteins, interfaces affect the aggregation reaction mainly through modulating the primary nucleation step. Moreover, we show through direct measurements of the Gibbs free energy of adsorption, combined with theory and coarse-grained computer simulations, that overall nucleation rates are suppressed at high and at low surface interaction strengths but significantly enhanced at intermediate strengths, and we verify these regimes experimentally. Taken together, these results provide a quantitative description of the fundamental process which triggers amyloid formation and shed light on the key factors that control this process.
Fluidic phase–change materials with continuous latent heat from theoretically tunable ternary metals for efficient thermal management
Authors: Wang Hua , Peng Yan , Peng Hao , Zhang Jiuyang
Published: July 2022

Phase–change materials (PCMs), as important energy storage materials (ESMs), have been widely used in heat dissipation for electronics. However, PCMs are encountering huge challenges since the extremely limited space in microelectronics largely suppresses the applied volume of PCMs, which demands excellent PCMs that can fully utilize the valuable latent heat. This work successfully found a universal strategy toward powerful ESMs from fluidic ternary metals (TMs, GaInSn as a representative TM in this work). TMs exhibit high thermal conductivity (20.3 W m−1K−1) and significantly effective latent heat (115 J/cm3) and, more important, show continuous phase transition and full utilization of the valuable latent heat. Interestingly, theoretical prediction through ternary phase diagram is carried out to easily tune the melting range, latent heat, and fluidity (viscosity) of TMs to adapt with different service conditions. As a result, thermally conductive silicone grease can be conveniently fabricated via simple shear mixing of TM and polymers. Such thermally conductive TM grease inherits the merits of TM, exhibiting continuous thermal control over daily electronics according to thermal shock performance.
Informing geometric deep learning with electronic interactions to accelerate quantum chemistry
Authors: Qiao Zhuoran , Christensen Anders S. , Welborn Matthew , Manby Frederick R. , Anandkumar Anima , Miller Thomas F.
Published: July 2022

Predicting electronic energies, densities, and related chemical properties can facilitate the discovery of novel catalysts, medicines, and battery materials. However, existing machine learning techniques are challenged by the scarcity of training data when exploring unknown chemical spaces. We overcome this barrier by systematically incorporating knowledge of molecular electronic structure into deep learning. By developing a physics-inspired equivariant neural network, we introduce a method to learn molecular representations based on the electronic interactions among atomic orbitals. Our method, OrbNet-Equi, leverages efficient tight-binding simulations and learned mappings to recover high-fidelity physical quantities. OrbNet-Equi accurately models a wide spectrum of target properties while being several orders of magnitude faster than density functional theory. Despite only using training samples collected from readily available small-molecule libraries, OrbNet-Equi outperforms traditional semiempirical and machine learning–based methods on comprehensive downstream benchmarks that encompass diverse main-group chemical processes. Our method also describes interactions in challenging charge-transfer complexes and open-shell systems. We anticipate that the strategy presented here will help to expand opportunities for studies in chemistry and materials science, where the acquisition of experimental or reference training data is costly.
The Supreme Court, the President, and Congress
Authors: Collins Paul M. , Eshbaugh-Soha Matthew
Published: July 2022

Presidents may react to Supreme Court decisions by supporting or opposing them in their public rhetoric and by calling on Congress to take action to alter or implement the Court’s decisions. We investigate this unique form of lawmaking using an original database of presidential calls to Congress and congressional reactions. We find that presidents call for congressional action to pursue their policy goals and enhance the power of the presidency; we also find that Congress reacts when it is asked to do so by both the Court and the president, as well as when presidents support the implementation of the Court’s decisions.
Numerical investigation on transient arc characteristics and anode surface temperature considering the electrode movement
Authors: Yang Ze , Wang Lijun , Zhang Zhefeng , Chen Jieli , Gortschakow Sergey
Published: July 2022

This work investigates the transient anode temperature and plasma parameters considering the electrode movement and the arc expansion. A transient self-consistent model is established using the dynamic mesh approach. Two cases with different maximum arc currents, representing various anode activity, have been studied. The simulations predict significant changes in spatial distribution of species densities, electron temperature and anode surface temperature in case with the anode spot formation. Furthermore, the influence of opening velocity on the plasma parameters has been studied numerically. The model was validated by comparison with experimental data for anode surface temperature as well as spectrally filtered arc images. Results of this comparison are presented and discussed.
Synergistic effect of Si concentration and distribution on ferroelectric properties optimization of Si:HfO2 ferroelectric thin films
Authors: Shao Yanping , Yang Wanting , Wang Yuanyao , Deng Yuhui , Liao Ningtao , Zhu Bingyan , Lin Xin , Jiang Limei , Jiang Jie , Yang Qiong , Zhong Xiangli
Published: July 2022

In this paper, a phase-field model of Si-doped hafnium oxide-based ferroelectric thin films is established. And then, the synergistic effect of Si concentration and distribution on ferroelectric properties optimization of Si:HfO2 ferroelectric thin films is studied with the proposed model. It is found that no matter how Si dopant is distributed in the film, the volume fraction of the ferroelectric phase in the film increases first and then decreases with the increase of Si concentration. However, compared with the uniform distribution, the layered distribution is more likely to great improve ferrelectric properties. When Si dopant is uniformly distributed in the film, the highest remanent polarization value that the film can obtain via Si concentration modulation is 38.7 μC cm−2, and the corresponding Si concentration is 3.8 cat%, which is consistent with the experimental results. When Si dopant is layered in the film, and the concentration difference between the Si-rich and Si-poor layers is 7.6%, in the Si concentration range of 3.6 cat%–3.8 cat%, the residual polarization of the film reaches 46.4–46.8 μC cm−2, which is 20% higher than that when Si dopant are evenly distributed in the film. The above results show that selecting the Si layered distribution mode and controlling the concentration difference between Si-rich and Si-poor layers in an appropriate range can greatly improve the films’ ferroelectric properties and broaden the Si concentration optimization range of the ferroelectric properties of the films. The result provides further theoretical guidance on using Si doping to adjust the ferroelectric properties of hafnium oxide-based films.
A new test method for evaluating the evaporative cooling efficiency of fabrics using a dynamic sweating hot plate
Authors: Gao Huipu , Shawn Deaton A , Barker Roger
Published: July 2022

The lack of direct measures of the ability of a fabric to cool the skin by liquid sweat evaporation is a critical gap in available laboratory tests for evaluating the comfort of active wear clothing materials. This paper describes a novel method designed to evaluate the evaporative cooling performance of fabrics in a protocol that simulates active wear, including sweating and drying periods, in a continuous one-step procedure. It uses a dynamic sweating hot plate to measure the latent heat absorbed by fabrics in sweat evaporation, and in drying after sweat absorption. The efficacy of the method is demonstrated using a selected set of high-wicking polyester and a cotton knit t-shirt material that have different moisture absorption, wicking and drying properties. The cooling efficiency test shows that high-wicking polyester fabrics provide larger evaporative cooling in the sweating phase, where it is more likely to convey cooling benefits to the skin. Cotton fabrics absorb more latent heat in the drying phase, where the cooling effect may contribute to chilling effects. It provides an ideal platform to observe the dynamic relationship between patterns of wicking and liquid moisture spreading in fabrics and the evaporative cooling provided by the test materials. It shows that the location of wicked moisture in the fabric is a critical determinant of potential cooling effects. It also shows that a fabric’s wicking ability is not always an accurate predictor of its cooling efficiency. This new test method has provided a unique tool for directly characterizing the cooling efficiency of clothing materials using a protocol that accurately simulates sweating generation and drying in actual active wear scenarios.
Theoretical study of extremely narrow plasmonic surface lattice resonances observed by MIM nanogratings under normal incidence in asymmetric environments
Authors: Yang Xiuhua , Xia Dunzhu , Li Jinhui
Published: July 2022

Nanoarray structures can support plasmonic surface lattice resonances (SLRs) with extremely narrow linewidths and huge electric field enhancement features, which are attractive applications in nanolasers, biochemical sensors, and nonlinear optics. However, current nanoarray structures located in an asymmetric dielectric environment with a refractive index contrast of 1.00/1.52 of the superstrate/substrate excite much poorer SLRs under normal incidence, which largely limits their application range. In this work, we report extremely narrow SLRs supported by one-dimensional metal–insulator–metal nanograting in asymmetric dielectric environments. The simulation results show that an SLRs with linewidth of 3.26 nm and quality factor of 233.2 can be excited under normal incidence. This high-quality SLRs is attributed to the interference formation between the out-of-plane dipole resonance mode and the out-of-plane quadrupole resonance mode. We also show that the resonance wavelength and quality factor can be tuned by changing the structure geometry and period, and we calculate the normal incidence SLRs quality factor to be up to 248 in 1.33/1.52 and 250 in 1.45/1.52. We expect the SLRs of this work to find potential applications in asymmetric dielectric environments.
High-performance Ti-doped ZnS thin film anode for lithium-ion batteries
Authors: Jiang Heng , Zeng Yibo , Zhang Jie , Chen Yanli , Guo Hang , Li Lei , Zhang Ying
Published: July 2022

Thin film microbattery is urgently needed to provide a long-term stable on-chip power for various kinds of microdevices or microsystems. Anode is a core component in thin film lithium ion microbattery, however, previous researches mostly focused on metal oxide or Si-based thin film anodes, and the reports of metal sulfide thin film anodes are limited. Herein, we present a new type of Ti-doped ZnS thin film fabricated by radio frequency (RF) magnetron co-sputtering. The Ti doping is designed to enhance the overall electrical conductivity of the ZnS thin film, since the insulation of ZnS is one of the major barriers to deliver its lithium storage performance. As an anode applied in lithium ion battery, the Ti-doped ZnS thin film exhibits good cycling stability up to 500 cycles at a current density of 1.0 A·g−1, and remains a higher specific capacity of 463.1 mAh·g−1 than that of the pure ZnS thin film, showing its better electrochemical reaction reversibility. The rate capability and EIS measurements manifest the more favorable electrochemical reaction kinetics of the Ti-doped ZnS thin film, moreover, the CV tests at various scan rates indicate the improved Li+ diffusion kinetics in the electrode after Ti doping.
An in-plane supercapacitor obtained by facile template method with high performance Mn–Co sulfide-based oxide electrode
Authors: Jiang Subin , Liu Feng , Ji Xiang , Yu Tengfei , Qiao Yi , Yang Baojuan , Gao Meizhen
Published: July 2022

Designing in-plane supercapacitors with high electrode materials selectivity is an indispensable approach to improve electrochemical performance. In this work, a facile template method was employed to fabricate in-plane supercapacitors. This template method could select any electrochemical active materials as electrode materials of in-plane supercapacitors. Hence, a high electrochemical performance material Mn–Co LDO-2S with optimized metal-sulfur bonds proportion and abundant sulfur vacancies was employed as electrode material of symmetrical in-plane supercapacitor (SPS). SPS exhibits excellent electrochemical performance finally, and has considerable area energy density 55.0 μWh cm−2 with an area power density of 0.7 mW cm−2. As a result, introducing sulfur atoms and sulfur vacancies are efficient approaches to improve electrode materials’ electrochemical performance, and template method that proposed in this work is a promising approach to widen selectivity of in-plane supercapacitors’ electrode materials.
Boosting photovoltaic performance for Sb2S3 solar cells by ionic liquid-assisted hydrothermal synthesis
Authors: Alarcón-Altamirano Yarimeth Ameyalli , Miranda-Gamboa Ramses Alejandro , Baron-Jaimes Agustin , Ortiz-Soto Karla Arlen , Rincon Marina Elizabeth , Jaramillo-Quintero Oscar Andrés
Published: July 2022

Bulk and surface trap-states in the Sb2S3 films are considered one of the crucial energy loss mechanisms for achieving high photovoltaic performance in planar Sb2S3 solar cells. Because ionic liquid additives offer interesting physicochemical properties to control the synthesis of inorganic material, in this work we propose the addition of 1-Butyl-3-methylimidazolium hydrogen sulfate (BMIMHS) into a Sb2S3 hydrothermal precursor solution as a facile way to fabricate low-defect Sb2S3 solar cells. Lower presence of small particles on the surface, as well as higher crystallinity are demonstrated in the BMIMHS-assisted Sb2S3 films. Moreover, analyses of dark current density-voltage J–V curves, surface photovoltage transient and intensity-modulated photocurrent spectroscopy have suggested that adding BMIMHS results in high-quality Sb2S3 films and a successful defect passivation. Consequently, the best-performing BMIMHS-assisted device exhibits a 15.4% power conversion efficiency enhancement compared to that of control device. These findings show that ionic liquid BMIMHS can effectively be used to obtain high-quality Sb2S3 films with low-defects and improved optoelectronic properties.
Fluorescence temperature sensing of NaYF4:Yb3+/Tm3+@NaGdF4:Nd3+/Yb3+ nanoparticles at low and high temperatures
Authors: Meng Mingzhou , Zhang Tianmei , Wang Jiaoyu , Cheng Zhenlong , Yang Jianghua , Qiao Xin , Wen Jian , Resch‑Genger Ute , Ou Jun
Published: July 2022

NaYF4:Yb3+/Tm3+@NaGdF4:Nd3+/Yb3+ upconversion nanoparticles were prepared using a solvothermal method, and the effects of key factors such as the content of sensitiser Nd3+ and Yb3+ on their luminescence properties were investigated. The nanoparticles are homogeneous in size and well dispersed. Under 808 nm excitation, it can produce strong upconversion fluorescence. At the same time, the nanoparticles have good temperature sensing properties at the thermally coupled energy levels of 700 and 646 nm for Tm3+. Using its fluorescence intensity ratio, accurate temperature measurements can be performed, and it has been found that it exhibits different temperature sensing properties in low and high-temperature regions. The maximum relative sensitivity was found to be 0.88% K−1 and 1.89% K−1 for the low-temperature region of 285–345 K and the high-temperature region of 345–495 K. The nanoparticles were applied to the internal temperature measurement of lithium batteries and the actual high-temperature environment, respectively, and were found to have good temperature measurement performance.
Fiber Bragg grating sensor for in situ substrate temperature measurement in a magnetron sputtering system
Authors: Jagannadha Raju S D V S , Haque S Maidul , Goud B Karthik , De Rajnarayan , Misal J S , Rao K Divakar
Published: July 2022

Fiber Bragg grating sensors are used to monitor physical parameters like temperature even in inaccessible, unconventional environments. One such application is monitoring the temperature of a substrate from the back surface like any conventional thermocouple sensor and simultaneously monitoring the temperature on the front surface, which is in contact with ion plasma in a magnetron sputtering system. Since thin film parameters depend on substrate temperature, precise measurement plays an important role and thermocouple-like sensors are erroneous when placed on the front side of a substrate exposed to ion plasma. The lateral variation of temperature on the front side for larger substrates also has been established at four different locations, exploiting the multiplexing capability of FBGs. In this report, we demonstrate and utilise the versatility and capability of fiber Bragg grating sensors for online monitoring of substrate temperatures during thin film deposition, for the first time to the best of our knowledge, on different types of substrates. FBG based approach is expected to significantly aid in better control of thin film devices.