bluuebunny/crossref_metadata_2025 huggingface dataset:
Three-dimensional human placenta-like bud synthesized from induced pluripotent stem cells
Authors: Sato Mai , Inohaya Asako , Yasuda Eriko , Mogami Haruta , Chigusa Yoshitsugu , Kawasaki Kaoru , Kawamura Yosuke , Ueda Yusuke , Takai Hiroshi , Mandai Masaki , Kondoh Eiji
Published: July 2021

Placental dysfunction is related to the pathogenesis of preeclampsia and fetal growth restriction, but there is no effective treatment for it. Recently, various functional three-dimensional organs have been generated from human induced-pluripotent cells (iPSCs), and the transplantation of these iPSCs-derived organs has alleviated liver failure or diabetes mellitus in mouse models. Here we successfully generated a three-dimensional placental organ bud from human iPSCs. The iPSCs differentiated into various lineages of trophoblasts such as cytotrophoblast-like, syncytiotrophoblast-like, and extravillous trophoblast-like cells, forming organized layers in the bud. Placental buds were transplanted to the murine uterus, where 22% of the buds were successfully engrafted. These iPSC-derived placental organ buds could serve as a new model for the study of placental function and pathology.
EPR evidence for α-triphenylstannylvinyl radicals in the O-directed hydrostannation of dialkylacetylenes with Ph3SnH/cat. Et3B/O2
Authors: Watson Hamish A. , Fielding Alistair J. , Hale Karl J.
Published: July 2021

Here we provide definitive EPR evidence for the existence of α-triphenylstannylvinyl radicals such as (Z)-2 in the low temperature O-directed free radical hydrostannation of dialkyl propargylic alcohols with Ph3SnH/cat. Et3B and O2 in PhMe.
Synthesis on inert surfaces
Authors: Lackinger Markus
Published: July 2021

Intriguing covalent nanostructures are synthesized on solid surfaces. While important reactions proceed exclusively on metal surfaces, light-induced couplings or deposition of pre-activated monomers pave the road to synthesis on inert surfaces.
Tuning emission color and improving the warm-white persistent luminescence of phosphor BaLu2Al2Ga2SiO12:Pr3+via Zn2+ co-doping
Authors: Yuan Weihong , Pang Ran , Tan Tao , Wu Haiyan , Wang Shangwei , Su Jiangyue , Wang Jiutian , Jiao Shengjian , Li Chengyu , Zhang Hongjie
Published: July 2021

A novel UV-activated persistent luminescent phosphor BaLu2Al2Ga2SiO12:Pr3+,Zn2+ with strong warm-white afterglow emissions has been synthesized and systematically investigated.
Chemical removal in waste stabilisation pond systems of varying configuration
Authors: Linge Kathryn L. , Liew Deborah , Gruchlik Yolanta , Busetti Francesco , Ryan Una , Joll Cynthia A.
Published: July 2021

Better chemical removal in waste stabilisation ponds was linked to the presence of a maturation pond, higher solar irradiation, and warmer temperatures.
Photoactuation of micromechanical devices by photochromic molecules
Authors: Angulo-Cervera José Elías , Piedrahita-Bello Mario , Brachňaková Barbora , Enríquez-Cabrera Alejandro , Nicu Liviu , Leichle Thierry , Mathieu Fabrice , Routaboul Lucie , Salmon Lionel , Molnár Gábor , Bousseksou Azzedine
Published: July 2021

We describe a microelectromechanical device actuated by photochromic molecules and we assess their mechanical and actuating properties.
A simplified point-of-care testing approach for preeclampsia blood biomarkers based on nanoscale field effect transistors
Authors: Pham Thuy Thi Thanh , Tran Duy Phu , Nguyen Minh Cong , Amen Mohamed Taha , Winter Marnie , Whitehead Clare , Toh Justine , Thierry Benjamin
Published: July 2021

We first present and pilot clinically validate a fully integrated, high-performance indium oxide nano-transistor biodiagnostic platform for rapid, accurate testing of preeclampsia without analytical equipment aids and minimum operator intervention.
Thermal manipulation and thermal rectification in π-stacked organic nanowires
Authors: Liu Bohai , Chen Yunyu , Xu Xiangfan
Published: July 2021

Precise control of thermal conduction of nanowires, both magnitude and direction, has been demonstrated, providing novel access for nanoscale thermal manipulation.
Combining PD-L1 inhibitors with immunogenic cell death triggered by chemo-photothermal therapy via a thermosensitive liposome system to stimulate tumor-specific immunological response
Authors: Yu Jie , He Xidong , Wang Zigui , Wang Yupeng , Liu Sha , Li Xiaoyuan , Huang Yubin
Published: July 2021

The combination of ICB and ICD induced by PTT and OXA significantly promoted antigen presentation and infiltration of CTLs, which inhibited the relapse, regeneration, and metastasis of tumor cells.
Cubic-like Co/NC composites derived from ZIF-67 with a dual control strategy of size and graphitization degree for microwave absorption
Authors: Tao Jiaqi , Xu Linling , Wan Li , Hou Jinsen , Yi Pengshu , Chen Ping , Zhou Jintang , Yao Zhengjun
Published: July 2021

MOFs with high tunability are considered ideal candidates as microwave-absorbing materials.
Palladium-catalyzed benzylic C(sp3)–H carbonylative arylation of azaarylmethyl amines with aryl bromides
Authors: Zhao Haoqiang , Hu Bowen , Xu Lijin , Walsh Patrick J.
Published: July 2021

Introduced is a method for the deprotonative carbonylation of azaarylmethyl amines with aryl bromides. The reaction employs a Pd(NIXANTPHOS)-based catalyst and takes place under 1 atm CO.
Dissecting the activation of insulin degrading enzyme by inositol pyrophosphates and their bisphosphonate analogs
Authors: Hostachy Sarah , Utesch Tillmann , Franke Katy , Dornan Gillian Leigh , Furkert David , Türkaydin Berke , Haucke Volker , Sun Han , Fiedler Dorothea
Published: July 2021

An efficient synthesis of non-hydrolyzable inositol pyrophosphate analogs was developed to subsequently investigate the regulation of insulin-degrading enzyme by these hyperphosphorylated signaling molecules.
The dynamic face of lipid membranes
Authors: Gupta Sudipta , Ashkar Rana
Published: July 2021

Lipid membranes envelope live cells and mediate vital biological functions through regulated spatiotemporal dynamics. This review highlights the role of neutron scattering, among other approaches, in uncovering the dynamic properties of lipid membranes.
Interplay between hysteresis and nonlocality during onset and arrest of flow in granular materials
Authors: Mowlavi Saviz , Kamrin Ken
Published: July 2021

Using continuum modeling as well as discrete-element simulations, we investigate how velocity-weakening and nonlocality explain characteristic features of the solid-like to liquid-like transition in granular materials.
Rotation reversal of a ratchet gear powered by active particles
Authors: Xu Guo-hao , Ai Bao-quan
Published: July 2021

Our setup can convert the random motion of active particles into the directional rotation of the ratchet gear. For a given asymmetric gear, we can observe the rotation reversal when tuning the system parameters.
Light-excited chemiresistive sensors integrated on LED microchips
Authors: Wang Xiao-Xue , Zhang Shuang , Liu Yuan , Dai Jiang-Nan , Li Hua-Yao , Guo Xin
Published: July 2021

With the rapid development of the internet of things, light-excited gas sensors have aroused great attention to meet the increasing demand for room-temperature devices with high portability and low power consumption.
The traditional herbal formulation, Jianpiyifei II, reduces pulmonary inflammation induced by influenza A virus and cigarette smoke in mice
Authors: Yu Xuhua , Cai Tiantian , Fan Long , Liang Ziyao , Du Qiuling , Wang Qi , Yang Zifeng , Vlahos Ross , Wu Lei , Lin Lin
Published: July 2021

Chronic obstructive pulmonary disease (COPD) is a worldwide chronic inflammatory lung disease, and influenza A virus (IAV) infection is a common cause of acute exacerbations of COPD (AECOPD). Therefore, targeting viral infections represents a promising strategy to prevent the occurrence and development of inflammatory flare ups in AECOPD. Jianpiyifei II (JPYFII) is a traditional herbal medicine used in China to treat patients with COPD, and its clinical indications are not well understood. However, investigation of the anti-inflammatory effects and underlying mechanism using an animal model of smoking have been reported in a previous study by our group. In addition, some included herbs, such as Radix astragali and Radix aupleuri, were reported to exhibit antiviral effects. Therefore, the aim of the present study was to investigate whether JPYFII formulation relieved acute inflammation by clearing the IAV in a mouse model that was exposed to cigarette smoke experimentally. JPYFII formulation treatment during smoke exposure and IAV infection significantly reduced the number of cells observed in bronchoalveolar lavage fluid (BALF), expression of proinflammatory cytokines, chemokines, superoxide production, and viral load in IAV-infected and smoke-exposed mice. However, JPYFII formulation treatment during smoke exposure alone did not reduce the number of cells in BALF or the expression of Il-6, Tnf-a, and Il-1β. The results demonstrated that JPYFII formulation exerted an antiviral effect and reduced the exacerbation of lung inflammation in cigarette smoke (CS)-exposed mice infected with IAV. Our results suggested that JPYFII formulation could potentially be used to treat patients with AECOPD associated with IAV infection.
Glycoursodeoxycholic acid ameliorates diet-induced metabolic disorders with inhibiting endoplasmic reticulum stress
Authors: Cheng Lele , Chen Tao , Guo Manyun , Liu Peining , Qiao Xiangrui , Wei Yuanyuan , She Jianqing , Li Bolin , Xi Wen , Zhou Juan , Yuan Zuyi , Wu Yue , Liu Junhui
Published: July 2021

Recent studies reveal that bile acid metabolite composition and its metabolism are changed in metabolic disorders, such as obesity, type 2 diabetes and metabolic associated fatty liver disease (MAFLD), yet its role and the mechanism remain largely unknown. In the present study, metabolomic analysis of 163 serum and stool samples of our metabolic disease cohort was performed, and we identified glycoursodeoxycholic acid (GUDCA), glycine-conjugated bile acid produced from intestinal bacteria, was decreased in both serum and stool samples from patients with hyperglycemia. RNA-sequencing and quantitative PCR results indicated that GUDCA alleviated endoplasmic reticulum (ER) stress in livers of high fat diet (HFD)-fed mice without alteration of liver metabolism. In vitro, GUDCA reduced palmitic acid induced-ER stress and -apoptosis, as well as stabilized calcium homeostasis. In vivo, GUDCA exerted effects on amelioration of HFD-induced insulin resistance and hepatic steatosis. In parallel, ER stress and apoptosis were decreased in GUDCA-treated mice as compared with vehicle-treated mice in liver. These findings demonstrate that reduced GUDCA is an indicator of hyperglycemia. Supplementation of GUDCA could be an option for the treatment of diet-induced metabolic disorders, including insulin resistance and hepatic steatosis, with inhibiting ER stress.
Chromospheric heating and generation of plasma outflows by impulsively generated two-fluid magnetoacoustic waves
Authors: Niedziela R. , Murawski K. , Poedts S.
Published: July 2021

Context. The origin of the heating of the solar atmosphere is still an unsolved problem. As the photosphere and chromosphere radiate more energy than the solar corona, it is challenging but important to reveal all the mechanisms that contribute to plasma heating there. Ion–neutral collisions could play an important role.

Aims. We aim to investigate the impulsively generated two-fluid magnetoacoustic waves in the partially ionized solar chromosphere and to study the associated heating and plasma outflows, which higher up may result in nascent solar wind.

Methods. To describe the plasma dynamics, we applied a two-fluid model in which ions+electrons and neutrals are treated as separate fluids. We solved the two-fluid equations numerically using the JOANNA code.

Results. We show that magnetoacoustic waves triggered in the photosphere by localised velocity pulses can steepen into shocks which heat the chromosphere through ion–neutral collisions. Pulses of greater amplitude heat plasma more effectively and generate larger plasma outflows. Rising the altitude at which the pulse is launched results in opposite effects, mainly in local cooling of the chromosphere and slower plasma outflows.

Conclusions. Even a solitary pulse results in a train of waves. These waves can transform into shock waves and release thermal energy, heating the chromosphere significantly. A pulse can drive vertical flows which higher up can result in the origin of the solar wind.
Planet formation in stellar binaries: global simulations of planetesimal growth
Authors: Silsbee Kedron , Rafikov Roman R.
Published: July 2021

Planet formation around one component of a tight, eccentric binary system such as γ Cephei (with semimajor axis around 20 AU) is theoretically challenging because of destructive high-velocity collisions between planetesimals. Despite this fragmentation barrier, planets are known to exist in such (so-called S-type) orbital configurations. Here we present a novel numerical framework for carrying out multi-annulus coagulation-fragmentation calculations of planetesimal growth, which fully accounts for the specifics of planetesimal dynamics in binaries, details of planetesimal collision outcomes, and the radial transport of solids in the disk due to the gas drag-driven inspiral. Our dynamical inputs properly incorporate the gravitational effects of both the eccentric stellar companion and the massive non-axisymmetric protoplanetary disk in which planetesimals reside, as well as gas drag. We identify a set of disk parameters that lead to successful planetesimal growth in systems such as γ Cephei or α Centauri starting from 1 to 10 km size objects. We identify the apsidal alignment of a protoplanetary disk with the binary orbit as one of the critical conditions for successful planetesimal growth: It naturally leads to the emergence of a dynamically quiet location in the disk (as long as the disk eccentricity is of order several percent), where favorable conditions for planetesimal growth exist. Accounting for the gravitational effect of a protoplanetary disk plays a key role in arriving at this conclusion, in agreement with our previous results. These findings lend support to the streaming instability as the mechanism of planetesimal formation. They provide important insights for theories of planet formation around both binary and single stars, as well as for the hydrodynamic simulations of protoplanetary disks in binaries (for which we identify a set of key diagnostics to verify).
Properties of galaxies with ring structures
Authors: Fernandez Julia , Alonso Sol , Mesa Valeria , Duplancic Fernanda , Coldwell Georgina
Published: July 2021

Aims. We present a statistical analysis of different characteristics of ringed spiral galaxies with the aim of assessing the effects of rings on disk galaxy properties.

Methods. We built a catalog of ringed galaxies from the Sloan Digital Sky Survey Data Release 14 (SDSS-DR14). Via visual inspection of SDSS images, we classified the face-on spiral galaxies brighter than g < 16.0 mag into galaxies with: an inner ring, an outer ring, a nuclear ring, both an inner and an outer ring, and a pseudo-ring. In addition to rings, we recorded morphological types and the existence of bars, lenses, and galaxy pair companions with or without interaction. With the goal of providing an appropriate quantification of the influence of rings on galaxy properties, we also constructed a suitable control sample of non-ringed galaxies with similar redshift, magnitude, morphology, and local density environment distributions to those of ringed ones.

Results. We found 1868 ringed galaxies, accounting for 22% of the full sample of spiral galaxies. In addition, within galaxies with ringed structures, 46% have an inner ring, 10% an outer ring, 20% both an inner and an outer ring, 6% a nuclear ring, and 18% a partial ring. Moreover, 64% of the ringed galaxies present bars. We also found that ringed galaxies have both a lower efficiency of star formation activity and older stellar populations (as derived with the Dn(4000) spectral index) with respect to non-ringed disk objects from the control sample. Moreover, there is a significant excess of ringed galaxies with red colors. These effects are more important for ringed galaxies that have inner rings and bars with respect to their counterparts that have some other types of rings and are non-barred. The color-magnitude and color-color diagrams show that ringed galaxies are mostly concentrated in the red region, while non-ringed spiral objects are more extended to the blue zone. Galaxies with ringed structures present an excess of high metallicity values compared to non-ringed ones, which show a 12 + Log(O/H) distribution toward lower values. These findings seem to indicate that rings are peculiar structures that produce an accelerating galactic evolution, strongly altering the physical properties of their host galaxies.
Obtaining humic materials by mechanochemical reduction
Authors: Yudina Natalya , Linkevich Elizaveta , Saveleva Anna , Lomovsky Oleg
Published: July 2021

In the study, a mechanochemical modification of peat was carried out, leading to an increase in the number of functional groups and an increase in the solubility of humic complexes with metals. It was shown that the mechanical activation of peat in the presence of Zn significantly increased the yield of extractable fulvic acids. An analysis of the spectral coefficients showed that humic and fulvic acids extracted from peat were characterized by an increased content of alcohol hydroxyl groups, C–O carbohydrate moieties, and carboxyl groups.
Effective building materials using technogenic waste and mineral raw materials
Authors: Berdnikova Liliya , Gorbunov Fedor , Lapin Andrey
Published: July 2021

The results of research on the development of compositions of construction materials for structural purposes based on technogenic waste and mineral raw materials are presented. The possibility of obtaining materials with a wide range of operational properties by the methods of slip casting (compressive strength of the samples based on chamotte and sand is 53.0–95.9 and 50.0-69.5 MPa, bending strength is 8.1–16.5 and 8.5–15.3 MPa, abrasion is 0.2–0.36 and 0.15–0.39 g/cm2, respectively) and semi-dry pressing (compressive strength of the samples based on chamotte and sand are 19.1–43.5 and 18.3–32.6 MParespectively) isdemonstrated.
Investigation of the parameters of the process of obtaining low-sulfur coke from heavy oil residues in the presence of a recycling agent
Authors: Buzayev Nurdaulet , Aubakirov Yermek , Akhmetova Firuza , Ibrayeva Manshuk , Sanyazova Shynar , Mukazhanova Zhazira
Published: July 2021

The current state of the oil refining industry is characterized by obtaining high-quality products that meet environmental requirements. An important issue is the deep processing of oil, as well as the use of oil waste as raw materials. In this regard, there is an interest in putting oil raw materials into operation through destructive processes: catalytic cracking, thermal cracking, visbreaking, coking, and processing of most of the oil waste. The article shows the possibility of producing coke with a low sulfur content from heavy oil waste from a domestic oil field. The physical and chemical properties of the extracted distillates are determined by chromatographic analysis and determined that the group-hydrocarbon composition corresponds to the composition of fractions obtained from primary atmospheric distillation. The process of obtaining of low-sulfur coke used as a conductor and oxidizer of electric current and raw materials in the production of structural material in the presence of a recycling agent from heavy oil waste from the Kumkol field was studied.
Preparation of metallic bismuth by reduction of bismuth formates in ethylene glycol medium
Authors: Mishchenko Kseniya V. , Yukhin Yurii M.
Published: July 2021

Nano -and microcrystalline bismuth metal powders consisting of spherical particles with a size of 150-250 nm were obtained by reducing bismuth formates in an ethylene glycol medium. The phase composition and morphology of the obtained reaction products were studied by X-ray phase and thermal analysis, differential scanning calorimetry, scanning and transmission electron microscopy. Using Uv-vis, it was shown that a bismuth-ethylene glycol complex is formed with an absorption maximum at 249 nm and an extinction coefficient of 5.7×103 (L mol-1 cm-1) in a solution of chloric acid at 23°C. The concentration of bismuth enhances to 0.018 g L-1 in the ethylene glycol medium with a gradual increase in the temperature to 60°C of the reaction mixture. Thermolysis of bismuth glycolate with a composition of Bi2(OCH2CH2O)3 is accompanied by the formation of metallic bismuth at 190°C, which is oxidized to a monoclinic modification of bismuth oxide when the temperature increases in the air.
Сocrystals of betulin with suberic acid: mechanochemical synthesis and thermal behavior
Authors: Mikhailovskaya Anastasiya , Myz Svetlana , Gerasimov Konstantin , Kuznetsova Svetlana , Shakhtshneider Tatyana
Published: July 2021

In this work, the cocrystals of betulin with suberic acid were prepared by liquid-assisted grinding method using solvents of different polarity. The formation of cocrystals was confirmed by means of powder X-ray diffraction, IR spectroscopy and thermal analysis. It was shown that under heating, a structural transformation occurred after water removal, followed by cocrystal dissociation.
Magnetic sorption materials for recovery of organic anions from aqueous solutions
Authors: Petrova Yuliya , Sevast’yanova Ekaterina , Mateyshina Yuliya
Published: July 2021

Layered double hydroxides (LDHs) belong to the class of two-dimensional anionic clays with a layered structure similar to brucite. The combination of sorption and magnetic properties of layered materials is promising. In this work, magnetic materials based on LDHs (MLDHs) were synthesized and their sorption and magnetic properties were studied. The synthesis of LDHs was carried out by a co-precipitation method followed by calcination. Intercalated Mg, Fe(III)-, Mg, Fe(III), Al-and Mg, Al-LDHs were prepared using LDHs by rehydration in solutions of iron(III) citrate (Cit) or oxalate (Ox) followed by the calcination at 400°C for 2-4 h. LDHs and their thermal decomposition products were characterized by FTIR spectroscopy, laser and X-ray diffraction and thermogravimetry. The sorption experiment was carried out under static conditions using glutamic acid (Glu) as a model organic compound. The maximum sorption capacity of Mg, Fe(III)-LDH and Mg, Al-FeCit-LDH calcined at 400°C was 6.6 and 8.8 mg/g Glu, respectively. The sorption kinetics of intercalated and calcined Mg, Al-and Mg, Fe(III), Al-LDH and calcined at 500º C Mg, Fe(III)-LDH was described by the pseudo-second order model. The magnetic properties of the LDHs and thermal decomposition products were retained after the adsorption of glutamic acid, making it possible to easily separate these MLDHs from the solution by magnetic field.
Study of the transport properties of composite solid electrolytes LiClO4-MgAl2O4
Authors: Alekseev Dmitriy , Khusnutdinov Vyacheslav , Mateyshina Yulia
Published: July 2021

Magnesium-aluminum spinel MgAl2O4was synthesized by mechanical treatment of a mixture of hydroxides followed by treatment of the solution at 80 ° C and sintering at 850° C. The obtained nanocrystalline sample with a specific surface area of 100 m2/g were used for the preparation of composite solid electrolytes (1-x) LiClO4-xMgAl2O4. It was shown that conductivity increases with the spinel concentration and goes through a maximum of 1.35·10-2S/cm at 150 °C for composite 0.3LiClO4-0.7MgAl2O4.
The application of zinc citrate for the synthesis of carbon materials
Authors: Sinelnikova Yuliya , Uvarov Nikolai
Published: July 2021

Zinc citrate was prepared and its thermal decomposition was investigated by methods of thermogravimetric analysis and differential scanning calorimetry. Products of the thermal decomposition were investigated by X-ray diffraction analysis. The decomposition proceeds at temperatures 50 - 420 °C in three stages and leads to the formation of nanocrystalline ZnO with the average grain size of 23 nm. Subsequently, zinc citrate was used as a precursor of ZnO hard template for preparation of carbon mesoporous materials by the solid template method. The carbon materials were obtained by pyrolysis of polymer matrix of phenol-formaldehyde resin in which zinc citrate was added. It was found that the resulting material has a specific surface area of 1051 m2/g. According to the cyclic voltamperometry data, the material has a specific capacity 40 F/g.
Development of composite electrode materials based on nickel oxide for additive manufacturing of fuel cells
Authors: Bagishev Artem , Titkov Alexander , Vorobyev Alexander , Borisenko Tatyana , Bessmeltsev Victor , Katasonov Denis , Nemudry Alexander
Published: July 2021

In this work, a new composition of a paste based on nanosized nickel oxide (NiO) for jet-based 3D printing has been developed and investigated. The optimal parameters of anode paste with necessary viscosity and NiO loading have been found for printing by using custom made laboratory 3D printer. Experiments have been carried out to print two-and three-dimensional test objects using the developed ceramic paste; printing modes have been investigated to fabricate objects of a given shape and size with laser sintering of the deposited layers. Experiments have been conducted for the selection of optimal temperature conditions for the post-processing of the printed samples.
Investigation into color designs of product packaging through visual evaluations using machine learning methods
Authors: Gao Yang
Published: July 2021

For a commodity, in addition to its quality, its external package is also very essential. This paper briefly introduced the intelligent support vector machine (SVM) algorithm for color design of paper packaging. The features were extracted from photos of packages using scale-invariant feature transform (SIFT), and the intelligent algorithm was trained and tested using photos of paper packaging for ceramic products collected at the ceramic crafts market as a sample set. Two paper package schemes designed in this study were used for further test. The SVM algorithm was compared with the back-propagation (BP) algorithm and the convolutional neural network (CNN) algorithm. The results showed that the three intelligent algorithms could evaluate the color design of paper packages, but the SVM algorithm was more accurate than the BP and CNN algorithms in evaluating the imagery of color design, both for the samples collected in the craft market and for the paper packaging scheme designed in this paper.
Inhalant Abuse of Ethyl Chloride Spray: A Case Report
Authors: Hager Laura , Kamp Felicia , Proebstl Lisa , Behle Nina , Pogarell Oliver , Koller Gabriele
Published: July 2021

Ethyl chloride spray, which is usually used to relieve pain after injuries, is
increasingly being used as a sniffing alternative. The number of people using
this is rising due to its easy availability, cost-effectiveness and legality.
The high lipid solubility of ethyl chloride leads to a rapid absorption of it in
the lungs. However, data on the biotransformation of ethyl chloride in humans
are sparse. We present the case of a 53-year-old male who had been inhaling
ethyl chloride up to 3 times a week since 25 years, and describe his symptoms
and the circumstances of abuse. This should help raise awareness of this issue
so that abuse can be recognized early and rapid action taken.
Semi-automated Conversion of Clinical Trial Legacy Data into CDISC SDTM Standards Format Using Supervised Machine Learning
Authors: Oda Takuma , Chiu Shih-Wei , Yamaguchi Takuhiro
Published: July 2021

Objective This study aimed to develop a semi-automated process to convert legacy data into clinical data interchange standards consortium (CDISC) study data tabulation model (SDTM) format by combining human verification and three methods: data normalization; feature extraction by distributed representation of dataset names, variable names, and variable labels; and supervised machine learning.

Materials and Methods Variable labels, dataset names, variable names, and values of legacy data were used as machine learning features. Because most of these data are string data, they had been converted to a distributed representation to make them usable as machine learning features. For this purpose, we utilized the following methods for distributed representation: Gestalt pattern matching, cosine similarity after vectorization by Doc2vec, and vectorization by Doc2vec. In this study, we examined five algorithms—namely decision tree, random forest, gradient boosting, neural network, and an ensemble that combines the four algorithms—to identify the one that could generate the best prediction model.

Results The accuracy rate was highest for the neural network, and the distribution of prediction probabilities also showed a split between the correct and incorrect distributions. By combining human verification and the three methods, we were able to semi-automatically convert legacy data into the CDISC SDTM format.

Conclusion By combining human verification and the three methods, we have successfully developed a semi-automated process to convert legacy data into the CDISC SDTM format; this process is more efficient than the conventional fully manual process.
An Analysis of Disorders Presenting at a Pediatric Neurology Outpatient Clinic: A Report from Turkey
Authors: Sarıkaya Emre , Yavuz Halûk
Published: July 2021

Neurological problems constitute an important part of diseases in children. Studies evaluating neurological diseases in children collectively and reporting their types and rates are very few. We report the clinical and laboratory spectra of children presenting with neurological diseases to our clinic. The charts of patients who presented for the first time to the only pediatric neurology outpatient clinic in the region during a year were evaluated retrospectively. A total of 88,785 patients were seen at the Meram Faculty of Medicine pediatric outpatient clinics in 1 year; 5.5% (4,904) of these patients were seen at the child neurology clinic and 1,807 patients (36.8%) were seen for the initial evaluation. Medical charts of 1,685 (93.2%) patients were reviewed: 952 (56.5%) were male patients and 733 were females. The mean age was 5.77 ± 4.92 years; 30.9% of the patients had a similar disease in the family. The top three presenting complaints that led to hospital seen were seizures (12.2%), paroxysmal events (10%), and headaches (9.2%). The most common diagnoses were epilepsy (18%), headache (8.6%), and developmental delay (7.8%). Our study describes the characteristics of the large number of patients seen for the first time in the child neurology outpatient clinic.
Observational Study on the Effect of Duration from Pediatric Advanced Life Support (PALS) Certification on PALS Performance in Pediatric Interns in Simulated Cardiopulmonary Arrest
Authors: Tofil Nancy M. , Gaither Stacy L. , Cohen Charli , Norwood Carrie , Zinkan Jerry Lynn , Raju Sai S. , Rutledge Chrystal
Published: July 2021

Pediatric advanced life support (PALS) training is critical for pediatric residents. It is unclear how well PALS skills are developed during this course or maintained overtime. This study evaluated PALS skills of pediatric interns using a validated PALS performance score following their initial PALS certification. All pediatric interns were invited to a 45-minute rapid cycle deliberate practice (RCDP) training session following their initial PALS certification from July 2017 to June 2019. The PALS score and times for key events were recorded for participants prior to RCDP training. We then compared performance scores for those who took PALS ≥3 months, between 3 days to 3 months and 3 days after PALS. There were 72 participants, 30 (of 30) in 3 days, 18 in 3 days to 3 months, and 24 in ≥3 months groups (42 total of 52 residents, 81%). The average PALS performance score was 53 ± 20%. There was no significant difference between the groups (3 days, 53 ± 15%; 3 days–3 months, 51 ± 19%; ≥3 months, 54 ± 26%, p = 0.922). Chest compressions started later in the ≥3 months groups compared with the 3 days or ≤3 months groups (p = 0.036). Time to defibrillation was longer in the 3 days group than the other groups (p = 0.008). Defibrillation was asked for in 3 days group at 97%, 73% in 3 days to 3 months and 68% in ≥3 months groups. PALS performance skills were poor in pediatric interns after PALS certification and was unchanged regardless of when training occurred. Our study supports the importance of supplemental resuscitation training in addition to the traditional PALS course.
Preimplantation Genetic Testing for Aneuploidy: Current Perspectives
Authors: L'Heveder Ariadne , Jones Benjamin P. , Naja Roy , Serhal Paul , Nagi Jara Ben
Published: July 2021

Despite improvements in assisted reproduction techniques (ARTs), live birth rates remain suboptimal, particularly in women with advanced maternal age (AMA). The leading cause of poor reproductive outcomes demonstrated in women with AMA, as well as women with recurrent miscarriage and repetitive implantation failure, is thought to be due to high rates of embryonic aneuploidy. Preimplantation genetic testing for aneuploidies (PGT-A) aims to select an euploid embryo for transfer and therefore improve ART outcomes. Early PGT-A studies using fluorescent in situ hybridization on mainly cleavage-stage biopsies failed to show improved delivery rates and, in certain cases, were even found to be harmful. However, the development of comprehensive chromosome screening, as well as improvements in culture media and vitrification techniques, has resulted in an emerging body of evidence in favor of PGT-A, demonstrating higher implantation, pregnancy, and live birth rates. While there are concerns regarding the potential harm of invasive biopsy and the cost implications of PGT-A, the introduction of noninvasive techniques and the development of new high-throughput methods which lower costs are tackling these issues. This review aims to assess the evidence for PGT-A, address possible concerns regarding PGT-A, and also explore the future direction of this technology.
Reproducibility of protein x-ray diffuse scattering and potential utility for modeling atomic displacement parameters
Authors: Su Zhen , Dasgupta Medhanjali , Poitevin Frédéric , Mathews Irimpan I. , van den Bedem Henry , Wall Michael E. , Yoon Chun Hong , Wilson Mark A.
Published: July 2021

Protein structure and dynamics can be probed using x-ray crystallography. Whereas the Bragg peaks are only sensitive to the average unit-cell electron density, the signal between the Bragg peaks—diffuse scattering—is sensitive to spatial correlations in electron-density variations. Although diffuse scattering contains valuable information about protein dynamics, the diffuse signal is more difficult to isolate from the background compared to the Bragg signal, and the reproducibility of diffuse signal is not yet well understood. We present a systematic study of the reproducibility of diffuse scattering from isocyanide hydratase in three different protein forms. Both replicate diffuse datasets and datasets obtained from different mutants were similar in pairwise comparisons (Pearson correlation coefficient ≥0.8). The data were processed in a manner inspired by previously published methods using custom software with modular design, enabling us to perform an analysis of various data processing choices to determine how to obtain the highest quality data as assessed using unbiased measures of symmetry and reproducibility. The diffuse data were then used to characterize atomic mobility using a liquid-like motions (LLM) model. This characterization was able to discriminate between distinct anisotropic atomic displacement parameter (ADP) models arising from different anisotropic scaling choices that agreed comparably with the Bragg data. Our results emphasize the importance of data reproducibility as a model-free measure of diffuse data quality, illustrate the ability of LLM analysis of diffuse scattering to select among alternative ADP models, and offer insights into the design of successful diffuse scattering experiments.
Laboratory diffracted x-ray blinking to monitor picometer motions of protein molecules and application to crystalline materials
Authors: Arai Tatsuya , Inamasu Rena , Yamaguchi Hiroki , Sasaki Daisuke , Sato-Tomita Ayana , Sekiguchi Hiroshi , Mio Kazuhiro , Tsuda Sakae , Kuramochi Masahiro , Sasaki Yuji C.
Published: July 2021

In recent years, real-time observations of molecules have been required to understand their behavior and function. To date, we have reported two different time-resolved observation methods: diffracted x-ray tracking and diffracted x-ray blinking (DXB). The former monitors the motion of diffracted spots derived from nanocrystals labeled onto target molecules, and the latter measures the fluctuation of the diffraction intensity that is highly correlated with the target molecular motion. However, these reports use a synchrotron x-ray source because of its high average flux, resulting in a high time resolution. Here, we used a laboratory x-ray source and DXB to measure the internal molecular dynamics of three different systems. The samples studied were bovine serum albumin (BSA) pinned onto a substrate, antifreeze protein (AFP) crystallized as a single crystal, and poly{2-(perfluorooctyl)ethyl acrylate} (PC8FA) polymer between polyimide sheets. It was found that not only BSA but also AFP and PC8FA molecules move in the systems. In addition, the molecular motion of AFP molecules was observed to increase with decreasing temperature. The rotational diffusion coefficients (DR) of BSA, AFP, and PC8FA were estimated to be 0.73 pm2/s, 0.65 pm2/s, and 3.29 pm2/s, respectively. Surprisingly, the DR of the PC8FA polymer was found to be the highest among the three samples. This is the first report that measures the molecular motion of a single protein crystal and polymer by using DXB with a laboratory x-ray source. This technique can be applied to any kind of crystal and crystalline polymer and provides atomic-order molecular information.
A mass-energy balance model for strongly magnetized argon discharges
Authors: Hyde A. , Batishchev O.
Published: July 2021

A semiempirical physical model of a strongly magnetized argon discharge is presented. Experimental extreme-ultraviolet (EUV) spectra are analyzed and photon emission is incorporated via the most important ground-state transitions for neutral and ionic species. Other major plasma processes are also included: ionization by electron impact, wall recombination, anomalous cross field diffusion, and charge-exchange. Plasma acceleration in the ambipolar electric field is treated phenomenologically. Specific power/mass flow densities and discharge vessel geometry are factorized into equations. The resultant non-linear system of normalized stiff ordinary differential equations describes the evolution of the temperatures and densities of the plasma components under the quasi-neutrality constraint. The equations are integrated numerically using a new unconditionally stable method. The transport coefficients are deduced from a two-point comparison to experimental data. Results of multiple parametric scans are presented and discussed in detail, with emphasis on plasma acceleration and EUV light production.
First principle study of anisotropic thermoelectric material: Sb2Si2Te6
Authors: Zhang Yuqian , Niu Chunping , He Hailong , Wu Yi , Rong Mingzhe , Yu Ke , Ren Hongrui
Published: July 2021

Layered thermoelectric (TE) materials have received widespread attention because of their inherent low lattice thermal conductivity and good TE properties. Recently, a new type of layered material Sb2Si2Te6 polycrystalline was reported to show high power factor (∼10.6μWcm−1K−2 at 579 K) and low thermal conductivity (0.69–0.74Wm−1K−1 at 823 K), which is a kind of very promising TE material. Considering that layered materials are usually anisotropic, we use first principles combined with Boltzmann’s transport equation to comprehensively predict the TE transport characteristics of single crystal p-type and n-type Sb2Si2Te6 in this study. The results show that the TE properties of Sb2Si2Te6 have obvious anisotropy. It has extremely low lattice thermal conductivity along the cross-plane direction. After the optimization of carrier concentration, the TE figure of merit of n-type Sb2Si2Te6 is much higher than that of the p-type. N-type Sb2Si2Te6 has good TE performance in the full temperature range [ZT=1.38 at 300 K, 3.54 at 500 K, 5.27 at 700 K (along the cross-plane direction); 1.97 at 300 K, 1.94 at 500 K, 3.08 at 700 K (along the in-plane direction)], and the optimal doping concentration at different temperatures is relatively close, showing its great potential in TE applications.
Particle-in-cell modeling of a potential demonstration experiment for double pulse enhanced target normal sheath acceleration
Authors: Rahman Nashad , Smith Joseph R. , Ngirmang Gregory K. , Orban Chris
Published: July 2021

Ultra-intense lasers are a promising source of energetic ions for various applications. An interesting approach described in Ferri et al. [Commun. Phys. 2, 40 (2019)] argues from particle-in-cell simulations that using two laser pulses of half energy (half intensity) arriving with close to 45° angle of incidence is significantly more effective at accelerating ions than one pulse at full energy (full intensity). For a variety of reasons, at the time of this writing, there has not yet been a true experimental confirmation of this enhancement. In this paper, we perform 2D particle-in-cell simulations to examine if a millijoule class, 5×1018 W cm−2 peak intensity laser system could be used for such a demonstration experiment. Laser systems in this class can operate at a kHz rate which should be helpful for addressing some of the challenges of performing this experiment. Despite investigating a 3.5 times lower intensity than Ferri et al. [Commun. Phys. 2, 40 (2019)] did, we find that the double pulse approach enhances the peak proton energy and the energy conversion to protons by a factor of about three compared to a single laser pulse with the same total laser energy. We also comment on the nature of the enhancement and describe simulations that examine how the enhancement may depend on the spatial or temporal alignment of the two pulses.
Influence of neutral depletion on blue core in argon helicon plasma
Authors: Zhang Tianliang , Cui Ruilin , Zhu Wanying , Yuan Qian , Ouyang Jiting , Jiang Kaiyin , Zhang Haibao , Wang Chenwen , Chen Qiang
Published: July 2021

Blue core (BC) is a special spectral phenomenon in argon helicon plasma, with intense blue lights from ion emission around the radial center of discharge tube. In this paper, the characteristics of BC in argon (Ar) helicon plasma were investigated experimentally from aspects of discharge mode transitions, plasma spatial distributions, and spectral features. It is found that the BC generally appears at strong magnetic field (480 G or above in this work) with high plasma density in wave mode, accompanied by exponentially rising of ion line intensity. The electron density and temperature, the neutral density and temperature, and the line emission intensity show a radial profile with a central peak in BC mode. The steep gradient of ion line intensity (corresponding to the ion density) defines a clear boundary of the core. Further, a pressure balance model was developed to investigate the influence of neutral depletion on BC formation. The neutral density is depleted significantly from 7.24×1013 to 0.38 × 1013 cm−3 at magnetic field of 600 G in BC mode, while to 3.13 × 1013 cm−3 at magnetic field of 250 G in normal wave (NW) mode. The ionization rate in BC reaches as high as 70% compared with 9.6% of that in NW mode. The ionization rate and the ion line intensity show similar radial profiles, indicating the BC phenomenon is closely related to the distribution of peaked ion density and hollowed neutral density. Fundamentally, the central electron heating and strong magnetic field contribute to the centrally local high ionization rate and strong neutral heating. The severe neutral depletion with prominent central heating is considered to be the immediate cause of appearance of blue core.
Self-terminating contactless photo-electrochemical (CL-PEC) etching for fabricating highly uniform recessed-gate AlGaN/GaN high-electron-mobility transistors (HEMTs)
Authors: Toguchi Masachika , Miwa Kazuki , Horikiri Fumimasa , Fukuhara Noboru , Narita Yoshinobu , Ichikawa Osamu , Isono Ryota , Tanaka Takeshi , Sato Taketomo
Published: July 2021

Contactless photo-electrochemical (CL-PEC) etching was used to fabricate recessed-gate AlGaN/GaN high-electron-mobility transistors (HEMTs). Self-termination of etching was observed during CL-PEC etching on an AlGaN barrier layer whose residual thickness had a uniform value of 6 nm overall on the same chip. After tetramethylammonium hydroxide post-treatment, the root-mean-square roughness of the etched surface was around 0.4 nm, which had smoothness comparable to that of the unetched surface. Recessed-Schottky HEMTs showed a positive shift in Vth, the suppression of drain leakage currents, and an improvement in the subthreshold-slope value as compared with planar-gate HEMTs. By applying a metal–insulator–semiconductor (MIS)-gate structure, the gate and drain leakage currents were significantly reduced, leading to an increased input dynamic range. Furthermore, the standard deviations (σ) of the Vth of CL-PEC-etched recessed-Schottky HEMTs and recessed-MIS HEMTs were very small, 5.5 and 16.7 mV, respectively. These results showed that the CL-PEC etching process is promising for the fabrication of recessed-gate AlGaN/GaN HEMTs having excellent uniformity for normally-off device operations.
Accurate density functional made more versatile
Authors: Jana Subrata , Behera Sushant Kumar , Śmiga Szymon , Constantin Lucian A. , Samal Prasanjit
Published: July 2021

We propose a one-electron self-interaction-free correlation energy functional compatible with the order-of-limit problem-free Tao–Mo (TM) semilocal functional (regTM) [J. Tao and Y. Mo, Phys. Rev. Lett. 117, 073001 (2016) and Patra et al., J. Chem. Phys. 153, 184112 (2020)] to be used for general purpose condensed matter physics and quantum chemistry. The assessment of the proposed functional for large classes of condensed matter and chemical systems shows its improvement in most cases compared to the TM functional, e.g., when applied to the relative energy difference of MnO2 polymorphs. In this respect, the present exchange–correction functional, which incorporates the TM technique of the exchange hole model combined with the slowly varying density correction, can achieve broad applicability, being able to solve difficult solid-state problems.
Relaxation dynamics of hot electrons in the transition metals Au, Ag, Cu, Pt, Pd, and Ni studied by ultrafast luminescence spectroscopy
Authors: Suemoto T. , Yamanaka K. , Sugimoto N. , Kobayashi Y. , Otsu T. , Tani S. , Koyama T.
Published: July 2021

The ultrafast relaxation dynamics of photoexcited electrons in six transition metals, Au, Ag, Cu, Pt, Pd, and Ni, were investigated using femtosecond luminescence spectroscopy in the infrared region between 0.4 and 1.05 eV. The behaviors of the time-resolved spectra are significantly different between group 11 noble metals (Au, Ag, and Cu) and group 10 transition metals (Pt, Pd, and Ni), which are neighbors in the periodic table of elements. In the latter group, the instantaneous luminescence intensities are one order of magnitude lower and the lifetimes (around 200 fs) are far shorter than those of the group 11 metals (typically 700 fs). The time-resolved spectra, decay profiles, and excitation power dependence were analyzed using a phenomenological model that considers both the nonthermal and thermal electrons. It was found that the nonthermal component is remarkably small in the group 10 transition metals. These systematic differences between group 10 and 11 metals are ascribed to the differences in their electron band structures and/or electron–phonon coupling strengths.