bluuebunny/crossref_metadata_2025 huggingface dataset:
Kuwaiti hospital patients’ continuance intention to use telemedical systems in the wake of the COVID19 pandemic
Authors: Almutairi Ibtisam L F H , Alazemi Bodoor F , Almutairi Faisal L F H
Published: December 2021

The objective of this study is to investigate factors influencing patients’ continuance intention to use telemedicine after the COVID‐19 pandemic in the medical sector of Kuwait. To reach this purpose, the updated Delone and Maclean (2003) model was utilized to investigate the aforementioned factors. As such, this research applied quantitative research methods with a sample of 290 participants from patients in Dar Al Shifa Hospital, a private hospital in Kuwait which utilizes telemedical services called ‘Sehaty online’. The corresponding data was analyzed using SmartPLS. The findings of this study revealed that information quality and system quality have a positive and significant influence on patient's satisfaction, whereas service quality has an insignificant influence on patient's satisfaction. Also, patients’ continuance intention to use telemedicine is found to be significantly impacted by their satisfaction. Furthermore, several limitations of the study, related future research, and recommendations have been discussed.
Cosmic-ray flux predictions and observations for and with Metis on board Solar Orbiter
Authors: Grimani C. , Andretta V. , Chioetto P. , Da Deppo V. , Fabi M. , Gissot S. , Naletto G. , Persici A. , Plainaki C. , Romoli M. , Sabbatini F. , Spadaro D. , Stangalini M. , Telloni D. , Uslenghi M. , Antonucci E. , Bemporad A. , Capobianco G. , Capuano G. , Casti M. , De Leo Y. , Fineschi S. , Frassati F. , Frassetto F. , Heinzel P. , Jerse G. , Landini F. , Liberatore A. , Magli E. , Messerotti M. , Moses D. , Nicolini G. , Pancrazzi M. , Pelizzo M. G. , Romano P. , Sasso C. , Schühle U. , Slemer A. , Straus T. , Susino R. , Teriaca L. , Volpicelli C. A. , Freiherr von Forstner J. L. , Zuppella P.
Published: December 2021

Context.The Metis coronagraph is one of the remote sensing instruments hosted on board the ESA/NASA Solar Orbiter mission. Metis is devoted to carry out the first simultaneous imaging of the solar corona in both visible light (VL) and ultraviolet (UV). High-energy particles can penetrate spacecraft materials and may limit the performance of the on-board instruments. A study of the galactic cosmic-ray (GCR) tracks observed in the first VL images gathered by Metis during the commissioning phase is presented here. A similar analysis is planned for the UV channel.

Aims.We aim to formulate a prediction of the GCR flux up to hundreds of GeV for the first part of the Solar Orbiter mission to study the performance of the Metis coronagraph.

Methods.The GCR model predictions are compared to observations gathered on board Solar Orbiter by the High-Energy Telescope in the range between 10 MeV and 100 MeV in the summer of 2020 as well as with the previous measurements. Estimated cosmic-ray fluxes above 70 MeV n−1have been also parameterized and used for Monte Carlo simulations aimed at reproducing the cosmic-ray track observations in the Metis coronagraph VL images. The same parameterizations can also be used to study the performance of other detectors.

Results.By comparing observations of cosmic-ray tracks in the Metis VL images with FLUKA Monte Carlo simulations of cosmic-ray interactions in the VL detector, we find that cosmic rays fire only a fraction, on the order of 10−4, of the whole image pixel sample. We also find that the overall efficiency for cosmic-ray identification in the Metis VL images is approximately equal to the contribution ofZ ≥ 2 GCR particles. A similar study will be carried out during the whole of the Solar Orbiter’s mission duration for the purposes of instrument diagnostics and to verify whether the Metis data and Monte Carlo simulations would allow for a long-term monitoring of the GCR proton flux.
SRG/ART-XC discovery of SRGA J204318.2+443815: Towards the complete population of faint X-ray pulsars
Authors: Lutovinov A. A. , Tsygankov S. S. , Mereminskiy I. A. , Molkov S. V. , Semena A. N. , Arefiev V. A. , Bikmaev I. F. , Djupvik A. A. , Gilfanov M. R. , Karasev D. I. , Lapshov I. Yu. , Medvedev P. S. , Shtykovsky A. E. , Sunyaev R. A. , Tkachenko A. Yu. , Anand S. , Ashley M. C. B. , De K. , Kasliwal M. M. , Kulkarni S. R. , van Roestel J. , Yao Y.
Published: December 2021

We report the discovery of the new long-period X-ray pulsar SRGA J204318.2+443815/SRGe J204319.0+443820 in a Be binary system. The source was found in the second all-sky survey by theMikhail PavlinskyART-XC telescope on board the SRG mission. The follow-up observations withXMM-Newton,NICER, andNuSTARallowed us to discover a strong coherent signal in the source light curve with a period of ~742 s. The pulsed fraction was found to depend on an increase in energy from ~20% in soft X-rays to >50% at high energies, as is typical for X-ray pulsars. The source has a quite hard spectrum with an exponential cutoff at high energies and a bolometric luminosity ofLX≃ 4 × 1035ergs-1. The X-ray position of the source is found to be consistent with the optical transient ZTF18abjpmzf, located at a distance of ~8.0 kpc. Dedicated optical and infrared observations with the RTT-150, NOT, Keck, and Palomar telescopes revealed a number of emission lines (Ha, He I, and the Paschen and Braket series) with a strongly absorbed continuum. According to the SRG scans and archivalXMM-Newtondata, the source flux is moderately variable (by a factor of 4-10) on timescales of several months and years. All this suggests that SRGA J204318.2+443815/SRGe J204319.0+443820 is a new quasi-persistent low-luminosity X-ray pulsar in a distant binary system with a Be-star of the B0-B2e class. Thus the SRG observatory allowed us to unveil a hidden population of faint objects, including a population of slowly rotating X-ray pulsars in Be systems.
Molecules, shocks, and disk in the axi-symmetric wind of the MS-type AGB star RS Cancri
Authors: Winters J. M. , Hoai D. T. , Wong K. T. , Kim W.-J. , Nhung P. T. , Tuan-Anh P. , Lesaffre P. , Darriulat P. , Le Bertre T.
Published: December 2021

Context. The latest evolutionary phases of low- and intermediate-mass stars are characterized by complex physical processes like turbulence, convection, stellar pulsations, magnetic fields, condensation of solid particles, and the formation of massive outflows that inject freshly produced heavy elements and dust particles into the interstellar medium.

Aims. By investigating individual objects in detail, we wish to analyze and disentangle the effects of the interrelated physical processes on the structure of the wind-forming regions around them.

Methods. We use the Northern Extended Millimeter Array to obtain spatially and spectrally resolved observations of the semi-regular asymptotic giant branch (AGB) star RS Cancri and apply detailed 3D reconstruction modeling and local thermodynamic equilibrium radiative transfer calculations in order to shed light on the morpho-kinematic structure of its inner, wind-forming environment.

Results. We detect 32 lines of 13 molecules and isotopologs (CO, SiO, SO, SO2, H2O, HCN, PN), including several transitions from vibrationally excited states. HCN, H13CN, and millimeter vibrationally excited H2O, SO, 34SO, SO2, and PN are detected for the first time in RS Cnc. Evidence for rotation is seen in HCN, SO, SO2, and SiO(v = 1). From CO and SiO channel maps, we find an inner, equatorial density enhancement, and a bipolar outflow structure with a mass-loss rate of 1 × 10−7 M⊙yr−1 for the equatorial region and of 2 × 10−7 M⊙yr−1 for the polar outflows. The 12CO/13CO ratio is measured to be ~20 on average, 24 ± 2 in the polar outflows and 19 ± 3 in the equatorial region. We do not find direct evidence of a companion that might explain this kind of kinematic structure, and explore the possibility that a magnetic field might be the cause of it. The innermost molecular gas is influenced by stellar pulsation and possibly by convective cells that leave their imprint on broad wings of certain molecular lines, such as SiO and SO.

Conclusions. RS Cnc is one of the few nearby, low-mass-loss-rate, oxygen-rich AGB stars with a wind displaying both an equatorial disk and bipolar outflows. Its orientation with respect to the line of sight is particularly favorable for a reliable study of its morpho-kinematics. Nevertheless, the mechanism causing early spherical symmetry breaking remains uncertain, calling for additional high spatial- and spectral-resolution observations of the emission of different molecules in different transitions, along with more thorough investigation of the coupling among the different physical processes at play.
Inference of electric currents in the solar photosphere
Authors: Pastor Yabar A. , Borrero J. M. , Quintero Noda C. , Ruiz Cobo B.
Published: December 2021

Context. Despite their importance, routine and direct measurements of electric currents, j, in the solar atmosphere have generally not been possible.

Aims. We aim at demonstrating the capabilities of a newly developed method for determining electric currents in the solar photosphere.

Methods. We employ three-dimensional radiative magneto-hydrodynamic (MHD) simulations to produce synthetic Stokes profiles in several spectral lines with a spatial resolution similar to what the newly operational 4-meter Daniel K. Inouye Solar Telescope solar telescope should achieve. We apply a newly developed inversion method of the polarized radiative transfer equation with magneto-hydrostatic (MHS) constraints to infer the magnetic field vector in the three-dimensional Cartesian domain, B(x, y, z), from the synthetic Stokes profiles. We then apply Ampere’s law to determine the electric currents, j, from the inferred magnetic field, B(x, y, z), and compare the results with the electric currents present in the original MHD simulation.

Results. We show that the method employed here is able to attain reasonable reliability (close to 50% of the cases are within a factor of two, and this increases to 60%–70% for pixels with B ≥ 300 G) in the inference of electric currents for low atmospheric heights (optical depths at 500 nm τ5∈[1, 0.1]) regardless of whether a small or large number of spectral lines are inverted. Above these photospheric layers, the method’s accuracy strongly deteriorates as magnetic fields become weaker and as the MHS approximation becomes less accurate. We also find that the inferred electric currents have a floor value that is related to low-magnetized plasma, where the uncertainty in the magnetic field inference prevents a sufficiently accurate determination of the spatial derivatives.

Conclusions. We present a method that allows the inference of the three components of the electric current vector at deep atmospheric layers (photospheric layers) from spectropolarimetric observations.
Dual-high-frequency VLBI study of blazar-jet brightness-temperature gradients and collimation profiles
Authors: Burd P. R. , Kadler M. , Mannheim K. , Baczko A.-K. , Ringholz J. , Ros E.
Published: December 2021

Context.On the kiloparsec scale, extragalactic radio jets show two distinct morphologies related to their power: collimated high-power jets ending in a bright termination shock and low-power jets opening up close to the core and showing a more diffuse surface brightness distribution. The emergence of this morphological dichotomy on the parsec scale at the innermost jet regions can be studied with very-long-baseline interferometry (VLBI) radio observations of blazars in which the jet emission is strongly Doppler boosted due to relativistic bulk motion at small angles between the jet direction and the line of sight.

Aims.We seek to characterize the geometry and emission profiles of the parsec-scale radio jets of flat-spectrum radio quasars (FSRQs) and BL Lacertae objects (BL Lacs) on parsec scales to derive properties of the magnetic field, environment, and energetics for different classes of extragalactic jets.

Methods.We analyze the VLBI radio data of 15 FSRQs, 11 BL Lacs, and two radio galaxies contained in both the Monitoring Of Jets in Active galactic nuclei with VLBA Experiments data archive and the Boston University blazar group sample archive at 15 GHz and 43 GHz, repectively. We derived the brightness-temperature and jet-width gradients along the jet axis from parameterizations of the jets using 2D Gaussian brightness distributions.

Results.In most BL Lac objects, the diameter and brightness-temperature gradients along the jet axis can generally be described well by single power laws, while the jets of FSRQs show more complex behavior and remain more strongly collimated on larger physical scales. We find evidence for a transition of the global jet geometry from a parabolic to a conical shape in the BL Lac objects 3C 66A, Mrk 421 and BL Lacertae, the radio galaxy 3C 111 and the FSRQs CTA 26, PKS 0528+134, 4C +71.07, 4C +29.45, and 3C 279 outside the Bondi sphere.

Conclusions.Our results combined with findings from kinematic VLBI studies that the jets of FSRQs exhibit larger bulk Lorentz factors than BL Lacs are in agreement with relativistic magnetohydrodynamical jet-disk simulations in which the flattening of the jet magnetization profile due to magnetic fields from the accretion disk leads to a more persistent collimation in high-accretion-rate blazars.
Sedimentary micro-phase and reservoir display characteristics in shale Oil
Authors: Xiao Cai
Published: December 2021

Sedimentary microphilic and its exhibition feature is of great significance for identifying the distribution of remaining oil. This paper studies the development of geological characteristics of Zhidan Oil Zone, mineralogue and scanning electron microscopy experiments, and obtains the sedimentary micro-phase and reservoir display characteristics. The results show that combined with logging data, the core phase analysis, logging phase analysis, single well phase analysis, etc. Taking the leading edge of the Delta, the microphase type such as the river, the diversion bay and the underwater natural embankment is developed under water, due to the lifting of the lake, form a number of invested, plus, replenishment, in which water The downstream river is facilitating the advantages of the reservoir. The sedimentary phase and the angle effect of the zone are dominated by 4 + 5, chang 6 oil and gas, showing the characteristics of the rock sex reservoir. The type of reservoir is a rock sex reservoir. The main development of sandstone is impaired and the sandstone lens is a rock sex reservoir. The reservoir is an important influencing factor in the reservoir. The area has no uniform oil and water interface, lacking edge, bottom water.
Data Model and Application of Pipeline Integrity Management
Authors: Dai Bingtao
Published: December 2021

Data is an important foundation and premise to ensure pipeline integrity management. Using data model to manage and utilize data is the key to implement pipeline integrity management, which can not only ensure the safety of oil and gas transportation, but also promote the stable development of China's social economy. Based on this, this paper deeply analyzes the development status of oil and gas pipeline integrity management data model, and makes an in-depth exploration on the establishment and application of oil and gas pipeline integrity data model by comparing various data models, combined with the current situation of oil and gas pipeline integrity management, and with the help of the advantages of apdm model, such as data set division and spatial information management.
Research and Practice of CO2 Flooding Technology in Ultra-low Permeability Reservoir of XX Oilfield
Authors: Zhou Wenxiu
Published: December 2021

CO2 flooding technology in ultra-low permeability reservoir is the key technology in modern oilfield technology development, which plays a key role in oilfield exploitation of ultra-low permeability reservoir. In this paper, CO2 flooding technology for ultra-low permeability reservoir in oilfield is analyzed and studied. The main characteristics of ultra-low permeability reservoir in oilfield are briefly analyzed, and the development of CO2 flooding technology is discussed. At the same time, the application of CO2 flooding technology in ultra-low permeability reservoir of XX Oilfield is studied and summarized.
A method for determining rational fluid production scale in conglomerate reservoir in the stage of high water cut
Authors: Liu Wentao , Wang Xiaodong , Zhang Chaoliang , Xue Rui , Zhu Guifang , Zhang Jifeng , Wei Xiaomin , Zhao Yanan
Published: December 2021

In view of the problem that water cut rises quickly in conglomerate reservoirs with high water cut, based on the variation law of reservoir water injection and liquid production characteristics, a method for determining the maximum liquid production scale in conglomerate reservoirs with high water cut is established by using reservoir engineering and field statistics.Considering the maximum liquid production capacity at the well end, the maximum injection capacity at the well end and the injecting-production ratio limit to keep the formation energy, a method to determine the maximum liquid production scale in conglomerate reservoir is established to keep the formation energy sufficient.This method ensures that the injection and production ends of the reservoir are coordinated and matched, and the formation energy is sufficient, so that the reservoir development keeps a benign cycle.The research method and conclusion have important reference value and significance for theoretical research and practical application of ultra-high water cut oilfield development.
Effect of nano pour point depressant on the flow properties of the waxy crude oil from Changqing Oilfield
Authors: Wen Huatao , Zhang Songzhao , Lian Yubo , Zhao Zhiguang , Wang Weibo , Wei Yajun , Duan Yu , Dong Sanbao
Published: December 2021

In this paper, graphene oxide (GO) was modified with alkyl amidopropyl diethanolamine to obtain a nano pour point depressant (GO-PPD), which was used to improve the flowability of the waxy oil extracted from Changqing Oilfield, China. Fourier transform infrared (FTIR), differential scanning calorimetry (DSC), polarized optical microscopy (POM) and viscometer were employed to evaluate the performance of the GOPPD. The results showed that compared with traditional pour point depressant (PPD), the GO-PPD exhibited higher performance in promoting the flowability of waxy crude oil. With the presence of 500 mg/kg GO-PPD in the waxy crude oil, the pour point of which could be reduced by 5.5 °C. Also, with the presence of 500 mg/kg GO-PPD, the viscosity reduction rate of the waxy crude oil can reach up to 52% at 30 °C. Through the observation via polarized microscopy, we have also found that with the introduction of GO-PPD in the crude oil, the formation of the wax crystals can be greatly retarded. This confirmed that the graphene oxide derivates could also be served as PPD, which facilitates the flowability of certain crude oil (e.g., waxy crude oil from Changqing Oilfield).
Application of distributed photovoltaic power generation technology in electric vehicles
Authors: Wu Min
Published: December 2021

In this paper, a photovoltaic grid connected electric vehicle charging station suitable for plateau application is developed by using two-way energy storage photovoltaic grid connected power generation technology; Introduce a medium-sized electric bus to carry out long-term operation test in Tibet; The detection experimental device and evaluation method suitable for electric vehicle power battery in plateau area are constructed; Carry out strategic research on the impact evaluation of the development of electric vehicles on the power grid side in the plateau weak current network area.
Study on Pre Pumping and Outburst Elimination Technology of “one hole and two elimination” in Bedding Directional Long Drilling
Authors: Yuan Benqing , Zhang Yongjiang
Published: December 2021

Aiming at the problem of gas control in the working face and the roadway to be excavated at the same time due to the small construction length of bedding borehole under the condition of the occurrence of soft coal, a technology of "one hole and two elimination" pre-drainage to eliminate gas outburst by using air screw motor drilling was put forward, and the field test was carried out in the 17102(3) working face of Pansu Coal Mine.The results show that this technology can effectively control the borehole trajectory, ensure the uniform and reasonable range of borehole outburst elimination, solve the problems of long gas treatment cycle caused by the construction of gas treatment roadway, improve the effective drainage time of borehole, ensure enough time and space for gas treatment, and be beneficial to the mining and replacement of mine.
Estimating highwall miner technical condition using vibration diagnostics methods
Authors: Gerike Boris , Tatsiyenko Viktor , Drozdenko Yuriy , Artamonov Pavel
Published: December 2021

Based on the results of Highwall Miner diagnostic testing, reference spectral masks for every component and assembly were built. They standardize vibration intensity level in different frequency domains of spectra and previously were used for estimating their technical conditions. Two-year period of monitoring proved the effectiveness of the approach for shifting to the system of preventative maintenance.
Patent analytics as a tool for mining machines
Authors: Korolev Mikhail , Nikitenko Sergey , Neogi Biswarup
Published: December 2021

The article analyses the possibility of conducting research on the competitive environment and assessing the potential effect of introducing promising technological solutions based on the use of patent landscapes even before the construction of new mining machines begins. The authors suggest that the oriented adaptation of patent analytics tools will allow solving a large-scale scientific problem. That is identifying patterns and dependences of changes in the main parameters of mining machines over time and developing a methodology for predicting and substantiating the promising parameters of various mining machines, both of one functional purpose and multifunctional ones, ensuring their efficient operation for a given period of time.
Implant Stability Changes for a Single Implant Mandibular Overdenture
Authors: Fouda Karim , Fahmy Ahmed , Aziz Khaled , Aal Marwa Abdel , Naguib Amr , Nabi Nouran Abdel
Published: December 2021

Objectives To compare the changes in implant stability for the nonsubmerged and submerged protocols for a single-implant retained mandibular overdenture using Cendres and Metaux Locator attachment throughout a 24-month follow-up.

Materials and Methods Eighty edentulous patients who were seeking to install a single implant in the midline of the completely edentulous mandible. At the day of implant installation, patients were randomized into two groups using sealed envelopes: the nonsubmerged and submerged groups. After 3 months of healing period, randomization using sealed envelopes was performed and patients were randomized to receive the Cendres and Metaux Locator attachment. The periotest readings were recorded using the Periotest M device, every 3 months for the first year and annually in the second year. The scope of this clinical trial focused only on results of the Cendres and Metaux attachment.

Statistical Analysis The Mann–Whitney U-test was used for comparison between study groups for independent samples. Two-sided p-values less than 0.05 were considered statistically significant.

Results There was no statistically significant difference between the mean periotest readings of both groups throughout the 24-month follow-up. Both groups showed an improvement in mean periotest readings with the submerged group tending to show greater stability at 6, 12, and 24-month follow-ups.

Conclusions The nonsubmerged and the submerged healing protocols resulted in reliable periotest readings with the submerged group showing greater improvement than the nonsubmerged, although this improvement is nonsignificant when using the Cendres and Metaux attachment for a single mandibular overdenture.
Defining Disparities in Cochlear Implantation through the Social Determinants of Health
Authors: Schuh Marissa , Bush Matthew L.
Published: December 2021

Hearing loss is a global public health problem with high prevalence and profound impacts on health. Cochlear implantation (CI) is a well-established evidence-based treatment for hearing loss; however, there are significant disparities in utilization, access, and clinical outcomes among different populations. While variations in CI outcomes are influenced by innate biological differences, a wide array of social, environmental, and economic factors significantly impact optimal outcomes. These differences in hearing health are rooted in inequities of health-related socioeconomic resources. To define disparities and advance equity in CI, there is a pressing need to understand and target these social factors that influence equitable outcomes, access, and utilization. These factors can be categorized according to the widely accepted framework of social determinants of health, which include the following domains: healthcare access/quality, education access/quality, social and community context, economic stability, and neighborhood and physical environment. This article defines these domains in the context of CI and examines the published research and the gaps in research of each of these domains. Further consideration is given to how these factors can influence equity in CI and how to incorporate this information in the evaluation and management of patients receiving cochlear implants.
Engaging Housestaff as Informatics Collaborators: Educational and Operational Opportunities
Authors: Shenson Jared A. , Jankovic Ivana , Hong Hyo Jung , Weia Benjamin , White Lee , Chen Jonathan H. , Eisenberg Matthew
Published: December 2021

Background In academic hospitals, housestaff (interns, residents, and fellows) are a core user group of clinical information technology (IT) systems, yet are often relegated to being recipients of change, rather than active partners in system improvement. These information systems are an integral part of health care delivery and formal efforts to involve and educate housestaff are nascent.

Objective This article develops a sustainable forum for effective engagement of housestaff in hospital informatics initiatives and creates opportunities for professional development.

Methods A housestaff-led IT council was created within an academic medical center and integrated with informatics and graduate medical education leadership. The Council was designed to provide a venue for hands-on clinical informatics educational experiences to housestaff across all specialties.

Results In the first year, five housestaff co-chairs and 50 members were recruited. More than 15 projects were completed with substantial improvements made to clinical systems impacting more than 1,300 housestaff and with touchpoints to nearly 3,000 staff members. Council leadership was integrally involved in hospital governance committees and became the go-to source for housestaff input on informatics efforts. Positive experiences informed members' career development toward informatics roles. Key lessons learned in building for success are discussed.

Conclusion The council model has effectively engaged housestaff as learners, local champions, and key informatics collaborators, with positive impact for the participating members and the institution. Requiring few resources for implementation, the model should be replicable at other institutions.
2.2 CuAAC in Peptidomimetics and Protein Mimics
Authors: Meuleman T. J. , Liskamp R. M. J.
Published: December 2021

The tremendous recent developments in click chemistry, including the impressive developments of strain-promoted cycloaddition reagents, all started with the copper-catalyzed azide–alkyne cycloaddition (CuAAC) reaction conceived by Meldal et al. and Sharpless et al. This led to a revolution of extremely important applications in the chemical, biological, medical, and materials sciences. It is fair to state that, especially in the synthesis of multifunctional and complex small-to-large biomolecular constructs, CuAAC has been indispensable. This has been particularly evident in the area of peptides, peptidomimetics, and protein mimics. These biomolecules play key roles in the various peptide–peptide, peptide–protein, and protein–protein interactions that are involved in many diseases and disorders, and peptide-based therapeutics can be important in this context. However, it is often important to improve the bioactivity and overall stability, and modulate the spatial structure, of peptide-based therapeutics. The incorporation of the 1,4-disubstituted 1,2,3-triazole moiety as a non-native structural element using CuAAC is explored in this chapter. The resulting incorporated triazole moiety can lead to structural surrogates of the amide bond and disulfide bond. As a consequence, CuAAC can be utilized toward introducing conformational constraints and stabilizing secondary structures of α-helices, β-sheets/turns, or loop-like structures. In addition, CuAAC can be used to combine various peptide sequences with molecular scaffolds to develop protein mimics that can find applications as synthetic vaccines and antibodies.
5 Sulfur Fluoride Exchange (SuFEx)
Authors: Giel M.-C. , Smedley C. J. , Moses J. E.
Published: December 2021

Sulfur Fluoride Exchange (SuFEx) click chemistry is a new generation technology for creating stable molecular connections with absolute reliability under metal-free conditions. SuFEx builds upon the fundamental principles of click chemistry by exploiting a unique blend of stability and latent reactivity of high oxidation state sulfur fluoride [e.g., S(VI)] functionalities to forge stable covalent linkages at connective SuFEx hubs. In this review, we focus mainly on the SuFEx hubs, sulfuryl fluoride (SO2F2), thionyl tetrafluoride (SOF4), ethenesulfonyl fluoride (ESF), 1-bromoethene-1-sulfonyl fluoride (BESF) and, 2-substituted alkyne-1-sulfonyl fluorides (SASFs). We describe each connector’s unique reactivity and their application to SuFEx click chemistry.
Air purifier location and position are key in reducing transmission of coronavirus aerosol
Authors: Cockshott Anne
Published: December 2021

Purifier configuration can significantly reduce particle concentrations in lecture halls.
Revisiting quantum Zeno effect and anti-Zeno effect: Universality vs non-universality
Authors: Na Kyungsun
Published: December 2021

Universality vs non-universality on the quantum Zeno effect and the anti-Zeno effect is discussed. It is well-known that the Zeno effect is a result of the branch point effect based on the constraint that the energy spectrum is bounded from below. On the other hand, we show that the anti-Zeno effect arises from the interference of multiple complex poles in the lower half energy plane on a larger time scale compared with the Zeno time. Since the production of extra complex poles depends on the characteristics of the interaction Hamiltonian, we emphasize that the anti-Zeno effect is model-dependent and non-universal, while the Zeno effect is a universal phenomenon independent of the form of the interaction.
Recent advances in radiation therapy and photodynamic therapy
Authors: Chong Li Ming , Tng Danny Jian Hang , Tan Laura Ling Ying , Chua Melvin Lee Kiang , Zhang Yong
Published: December 2021

In the past 100 years, external beam energy for the treatment of cancer has continually evolved. Two main modes have been developed. The first is radiotherapy which involves using x-ray, gamma, and proton beams to cause ionizing damage. The second is photodynamic therapy, which uses photons to activate photosensitizers to generate reactive oxidating species causing cytotoxicity. For decades, these two fields have developed separately, with photodynamic therapy being used for treating surface tumors and radiotherapy, for deeper tumors. In the first half of this article, a detailed review of radiotherapy and photodynamic therapy will be presented. For each field, the underlying physical mechanisms will be discussed, followed by the existing technological and engineering designs, and ending off with the relevant vivo studies and clinical applications. In the second half, the recent efforts to combine radiotherapy and photodynamic therapy, leading to the generation of new techniques such as x-ray photodynamic therapy, proton-induced photodynamic therapy and even the possibility of hybrid approaches such as intensity and fluence modulated photodynamic therapy will be discussed. This new field is known as radiodynamic therapy. It has the potential to achieve increased conformality in the treatment of cancer, dealing maximal dosage to the lesion while sparing healthy tissues, paving the way for new advances in precision medicine. The connection between these fields is a neglected area, and this review addresses this gap. It also serves as a repository for researchers who are keen to venture into radiodynamic therapy.
Reducing indoor particle exposure using mobile air purifiers—Experimental and numerical analysis
Authors: Tobisch Adrian , Springsklee Lukas , Schäfer Lisa-Franziska , Sussmann Nico , Lehmann Martin J. , Weis Frederik , Zöllner Raoul , Niessner Jennifer
Published: December 2021

Aerosol particles are one of the main routes of transmission of COVID-19. Mobile air purifiers are used to reduce the risk of infection indoors. We focus on an air purifier that generates a defined volumetric air flow through a highly efficient filter material. We investigate the transport of aerosol particles from an infected dummy equipped with an aerosol generator to receiving thermal dummies. For analysis, we use up to 12 particle sensors to monitor the particle concentration with high spatial resolution. Based on the measurement data, a computational fluid dynamics (CFD) model is set up and validated. The experimental and numerical methods are used to investigate how the risk of infection suggested by the particle exposure in an exemplary lecture hall can be reduced by a clever choice of orientation of the air purifier. It turns out that obstructing the outlet stream of the air purifier may be particularly advantageous. The particle concentration at the head height deviates by 13% for variations of the location and orientation. At an air change per hour of 5, the cumulated PM1 mass at the head level was reduced by 75%, independently of the location of the infected dummy, compared to the “natural decay” case, showing that filtration is an effective means of reducing aerosol particle concentrations. Finally, CFD simulation was used to monitor the particle fates. The steady simulation results fit quite well with the experimental findings and provide additional information about the particle path and for assessing the comfort level due to air flow.
IUPAC–NIST Solubility Data Series. 105. Solubility of Solid Alkanoic Acids, Alkenoic Acids, Alkanedioic Acids, and Alkenedioic Acids Dissolved in Neat Organic Solvents, Organic Solvent Mixtures, and Aqueous–Organic Solvent Mixtures. II. Alkenoic and Alkynoic Acids
Authors: Acree William E. , Waghorne W. Earle
Published: December 2021

Solubility data are compiled and reviewed for ten alkenoic acids and one alkynoic acid dissolved in neat organic mono-solvents. The compiled solubility data were retrieved from the published chemical, engineering, and pharmaceutical literature covering the period from 1910 to the beginning of 2021.
Identifying the Dirac point composition in Bi1−xSbx alloys using the temperature dependence of quantum oscillations
Authors: Kang Joon Sang , Vu Dung , Heremans Joseph P.
Published: December 2021

The thermal chiral anomaly is a new mechanism for thermal transport that occurs in Weyl semimetals (WSMs). It is attributed to the generation and annihilation of energy at Weyl points of opposite chirality. The effect was observed in the Bi1−xSbx alloy system, at x = 11% and 15%, which are topological insulators at zero field and driven into an ideal WSM phase by an external field. Given that the experimental uncertainty on x is of the order of 1%, any systematic study of the effect over a wider range of x requires precise knowledge of the transition composition xc at which the electronic bands at the L-point in these alloys have Dirac-like dispersions. At x > xc, the L-point bands are inverted and become topologically non-trivial. In the presence of a magnetic field along the trigonal direction, these alloys become WSMs. This paper describes how the temperature dependence of the frequency of the Shubnikov–de Haas oscillations F(x,T) at temperatures of the order of the cyclotron energy can be used to find xc and characterize the topology of the electronic Fermi surface. Semimetallic Bi1−xSbx alloys with topologically trivial bands have dF(x,T)/dT ≥ 0; those with Dirac/Weyl fermions display dF(x,T)/dT < 0.
High resolution laser Thomson scattering system with automatic data analysis software platform for diagnosis of the low-temperature plasmas
Authors: Wang Yong , Shi Jielin , Li Yu , Zhao Yarui , Li Cong , Feng Chunlei , Ding Hongbin
Published: December 2021

Accurate measurements of electron temperature (Te) and electron density (ne) are important for understanding the properties of plasma, especially for the low-temperature plasma dominated by the free electrons. In this work, a high resolution laser Thomson scattering (LTS) diagnosis system with a software platform for processing data is established to accurately measure the Te and ne in low-temperature plasmas. In this system, a homemade Triple Grating Spectrometer (TGS) is elaborated to suppress the intense stray light and Rayleigh scattering light. The TGS with high etendue (with an f-number of f/3.3) and high spectral resolution (0.07 nm in full-width-half-maximum at 532 nm) allows the LTS system to measure the plasma with the ne and Te as low as 1.0 × 1017 m−3 and 0.1 eV, respectively. Besides the development of the experimental setup, a software platform is specially designed to automatically process the complicated LTS spectra to determine ne and Te in real time during the acquirement of data. The error analyses indicate that the uncertainty of ne is around 12% and the uncertainty of Te is about 10% when Te > 0.2 eV. Using the LTS system, we have successfully measured ne and Te in the cascaded arc plasma, nanosecond pulse discharge plasma, and inductively coupled plasma. The results demonstrate that the LTS system has significant potential for the diagnosis of various low temperature plasmas.
Structures of glass-forming liquids by x-ray scattering: Glycerol, xylitol, and D-sorbitol
Authors: Chen Zhenxuan , Huang Chengbin , Yao Xin , Benmore Chris J. , Yu Lian
Published: December 2021

Synchrotron x-ray scattering has been used to investigate three liquid polyalcohols of different sizes (glycerol, xylitol, and D-sorbitol) from above the glass transition temperatures Tg to below. We focus on two structural orders: the association of the polar OH groups by hydrogen bonds (HBs) and the packing of the non-polar hydrocarbon groups. We find that the two structural orders evolve very differently, reflecting the different natures of bonding. Upon cooling from 400 K, the O⋯O correlation at 2.8 Å increases significantly in all three systems, indicating more HBs, until kinetic arrests at Tg; the increase is well described by an equilibrium between bonded and non-bonded OH with ΔH = 9.1 kJ/mol and ΔS = 13.4 J/mol/K. When heated above Tg, glycerol loses the fewest HBs per OH for a given temperature rise scaled by Tg, followed by xylitol and by D-sorbitol, in the same order the number of OH groups per molecule increases (3, 5, and 6). The pair correlation functions of all three liquids show exponentially damped density modulations of wavelength 4.5 Å, which are associated with the main scattering peak and with the intermolecular C⋯C correlation. In this respect, glycerol is the most ordered with the most persistent density ripples, followed by D-sorbitol and by xylitol. Heating above Tg causes faster damping of the density ripples with the rate of change being the slowest in xylitol, followed by glycerol and by D-sorbitol. Given the different dynamic fragility of the three liquids (glycerol being the strongest and D-sorbitol being the most fragile), we relate our results to the current theories of the structural origin for the difference. We find that the fragility difference is better understood on the basis of the thermal stability of HB clusters than that of the structure associated with the main scattering peak.
Mesoscopic Boltzmann model equations for thermally perfect gases
Authors: Mathiaud J. , Mieussens L.
Published: December 2021

We propose a way to derive Bhatnagar–Gross–Krook and Fokker–Planck models of the Boltzmann equation for rarefied flows of thermally perfect gases. These models can allow for various internal energies (rotation, vibration, electronic), which is required for high temperature flows, like in atmospheric reentry problems. However, our models do not contain any internal degrees of freedom; instead, they are accounted for by a mesoscopic approach. The molecular velocity is the only kinetic variable in the models that makes their computational complexity similar to that of simple monatomic gases. Moreover, we prove that these models satisfy conservation and entropy properties (H-theorem), and we derive their corresponding compressible Euler and Navier–Stokes asymptotics gases.
Review of Scientific Instruments New Products
Authors: Mandelis Andreas
Published: December 2021

In order to supplement manufacturers’ information, this department will welcome the submission by our readers of brief communications reporting measurements on the physical properties of materials that supersede earlier data or suggest new research applications.
Medical detransition following transgender identity reaffirmation: two case reports
Authors: Expósito-Campos Pablo , Gómez-Balaguer Marcelino , Hurtado-Murillo Felipe , García-Moreno Rosa M. , Morillas-Ariño Carlos
Published: December 2021

Background Recently, increased social and scientific attention has been paid to gender detransition, a phenomenon in which individuals discontinue gender-affirming medical interventions (GAMI) aimed at alleviating gender dysphoria (GD). Yet, clinical knowledge of detransitioners and their experiences is still scarce. Case reports published in the literature suggest that both internal and external factors may influence this decision. Methods Two transgender individuals treated for GD at a gender identity unit presented with a desire to discontinue GAMI. A description of their clinical evolution is presented. Results Increased body satisfaction, self-esteem, self-acceptance, and self-empowerment with respect to their transgender identity were mentioned by the patients as reasons for discontinuing gender-affirming treatments. Coinciding factors included reduced GD, positive changes in social environments, better interpersonal functioning, and higher levels of psychological well-being in general. Conclusions Gender detransition is an under-researched phenomenon. These cases highlight the need for a more nuanced approach to gender-related clinical presentations, which involves providing individuals the opportunity to work on their social ecosystems and explore alternative options to manage GD before initiating GAMI.
Endocytic proteins with prion-like domains form viscoelastic condensates that enable membrane remodeling
Authors: Bergeron-Sandoval Louis-Philippe , Kumar Sandeep , Heris Hossein Khadivi , Chang Catherine L. A. , Cornell Caitlin E. , Keller Sarah L. , François Paul , Hendricks Adam G. , Ehrlicher Allen J. , Pappu Rohit V. , Michnick Stephen W.
Published: December 2021

Significance

The uptake of molecules into cells, known as endocytosis, requires membrane invagination and the formation of vesicles. A version of endocytosis that is independent of actin polymerization is aided by the assembly of membraneless biomolecular condensates at the site of membrane invagination. Here, we show that endocytic condensates are viscoelastic bodies that concentrate key proteins with prion-like domains to enable membrane remodeling. A distinct molecular grammar, namely the preference for glutamine versus asparagine residues, underlies the cohesive interactions that give rise to endocytic condensates. We incorporate material properties inferred using active rheology into a mechanical model to explain how cohesive interactions within condensates and interfacial tensions among condensates, membranes, and the cytosol can drive membrane invagination to initiate endocyosis.
NFAT-dependent and -independent exhaustion circuits program maternal CD8 T cell hypofunction in pregnancy
Authors: Lewis Emma L. , Xu Rong , Beltra Jean-Christophe , Ngiow Shin Foong , Cohen Jordana , Telange Rahul , Crane Alexander , Sawinski Deirdre , Wherry E. John , Porrett Paige M.
Published: December 2021

Pregnancy is a common immunization event, but the molecular mechanisms and immunological consequences provoked by pregnancy remain largely unknown. We used mouse models and human transplant registry data to reveal that pregnancy induced exhausted CD8 T cells (Preg-TEX), which associated with prolonged allograft survival. Maternal CD8 T cells shared features of exhaustion with CD8 T cells from cancer and chronic infection, including transcriptional down-regulation of ribosomal proteins and up-regulation of TOX and inhibitory receptors. Similar to other models of T cell exhaustion, NFAT-dependent elements of the exhaustion program were induced by fetal antigen in pregnancy, whereas NFAT-independent elements did not require fetal antigen. Despite using conserved molecular circuitry, Preg-TEX cells differed from TEX cells in chronic viral infection with respect to magnitude and dependency of T cell hypofunction on NFAT-independent signals. Altogether, these data reveal the molecular mechanisms and clinical consequences of maternal CD8 T cell hypofunction and identify pregnancy as a previously unappreciated context in which T cell exhaustion may occur.
Deep Learning Quantum States for Hamiltonian Estimation
Authors: Ma Xinran , Tu Z. C. , Ran Shi-Ju
Published: December 2021

Human experts cannot efficiently access physical information of a quantum many-body states by simply “reading” its coefficients, but have to reply on the previous knowledge such as order parameters and quantum measurements. We demonstrate that convolutional neural network (CNN) can learn from coefficients of many-body states or reduced density matrices to estimate the physical parameters of the interacting Hamiltonians, such as coupling strengths and magnetic fields, provided the states as the ground states. We propose QubismNet that consists of two main parts: the Qubism map that visualizes the ground states (or the purified reduced density matrices) as images, and a CNN that maps the images to the target physical parameters. By assuming certain constraints on the training set for the sake of balance, QubismNet exhibits impressive powers of learning and generalization on several quantum spin models. While the training samples are restricted to the states from certain ranges of the parameters, QubismNet can accurately estimate the parameters of the states beyond such training regions. For instance, our results show that QubismNet can estimate the magnetic fields near the critical point by learning from the states away from the critical vicinity. Our work provides a data-driven way to infer the Hamiltonians that give the designed ground states, and therefore would benefit the existing and future generations of quantum technologies such as Hamiltonian-based quantum simulations and state tomography.