bluuebunny/crossref_metadata_2025 huggingface dataset:
Ecofriendly synthesis and characterization of Ni2+ codoped silica magnesium zirconium copper nanoceramics for wastewater treatment applications
Authors: Mansour A. M. , Hemdan Bahaa A. , Elzwawy Amir , Abou Hammad Ali B. , El Nahrawy Amany M.
Published: June 2022

This article investigates the effect of Ni2+ content on structural (XRD, XPS), morphological (TEM), and magnetic behaviors of silica magnesium zirconium copper nanoceramics calcined at 800 °C. The sol–gel route is followed for the silica magnesium zirconium copper/(0.0–0.7) Ni2+ samples preparation. X-ray photoelectron spectroscopy is employed to analyze the chemical states of elements for the samples. The three representative binding energy magnitudes for O, Ni, and Cu reside at 534, 857, and 979 eV, consecutively. The saturation magnetization constricts with the elevation of Ni2+ content, while the magnetic hysteresis loop resembles the superparamagnetic attitude. The optical spectra present the possibility of direct and indirect transitions in the prepared nanoceramics. Energy gap (value and type), refractive index, and real and imaginary dielectric constant were extracted. The energy gap approaches 3.75 eV and 3.71 eV for direct and indirect transitions correspondingly with (0.7) Ni2+. The antimicrobial and the toxicity performance of all inspected nanocomposites were conducted against pathogenic microbes. The attained results evidenced that SMZC-0.7Ni possesses energetic antimicrobial potential against all targeted microbes. The investigated SMZC-0.7Ni nanocomposite functioned to eradicate frequent waterborne pathogens in wastewater at an appropriate dose (100 mg/L), demonstrating that SMZC can be utilized as a competent disinfectant in the municipal wastewater decontamination process. Inherently, SMZC-0.7Ni can be employed as an excellent nano-weapon against multiple dangerous microorganisms.
Amorphous carbon nitride dual-function anti-reflection coating for crystalline silicon solar cells
Authors: Addie Ali J. , Ismail Raid A. , Mohammed Mudhafar A.
Published: June 2022

Crystalline silicon (c-Si) solar cells have dominated the photovoltaic industry for decades. However, due to high reflectivity and the presence of numerous types of surface contaminants, the solar cell only absorbs a limited amount of the incident solar radiation. To improve the efficiency of the solar cell, anti-reflection and self-cleaning coatings must be applied to the surface. The main objective of this work is to synthesize an amorphous carbon nitride CNx thin film as a novel dual-function anti-reflection coating (ARC) for c-Si solar cells. The CNx film was synthesized by the RF magnetron sputtering technique and characterized by different chemical, structural, and optical analysis techniques. The performance of CNx film was investigated via measuring the reflectance, photoelectric conversion efficiency, and external quantum efficiency. The minimum reflectance was 0.3% at 550 nm wavelength, and the external quantum efficiency achieved was more than 90% within the broad wavelength range. The open circuit voltage and short circuit current density that have been achieved are 578 mV and 33.85 mAcm−2, respectively. Finally, a photoelectric conversion efficiency of 13.05% was achieved with the coated c-Si solar cell in comparison with 5.52% for the uncoated c-Si solar cell. This study shows that CNx films have promising application potential as an efficient ARC for c-Si solar cells as compared to traditional ARC materials.
Transgenic Forsythia plants expressing sesame cytochrome P450 produce beneficial lignans
Authors: Koyama Tomotsugu , Matsumoto Erika , Okuda Toshimi , Murata Jun , Horikawa Manabu , Hata Naoki , Okazawa Atsushi , Ono Eiichiro , Satake Honoo
Published: June 2022

Lignans are widely distributed plant secondary metabolites that have received attention for their benefits to human health. Sesamin is a furofran lignan that is conventionally extracted from Sesamum seeds and shows anti-oxidant and anti-inflammatory activities in the human liver. Sesamin is biosynthesized by the Sesamum-specific enzyme CYP81Q1, and the natural sources of sesamin are annual plants that are at risk from climate change. In contrast, Forsythia species are widely distributed perennial woody plants that highly accumulate the precursor lignan pinoresinol. To sustainably supply sesamin, we developed a transformation method for Forsythia leaf explants and generated transgenic Forsythia plants that heterologously expressed the CYP81Q1 gene. High-performance liquid chromatography (HPLC) and LC-mass spectrometry analyses detected sesamin and its intermediate piperitol in the leaves of two independent transgenic lines of F. intermedia and F. koreana. We also detected the accumulation of sesamin and piperitol in their vegetatively propagated descendants, demonstrating the stable and efficient production of these lignans. These results indicate that CYP81Q1-transgenic Forsythia plants are promising prototypes to produce diverse lignans and provide an important strategy for the cost-effective and scalable production of lignans.
Pile caps with inclined shear reinforcement and steel fibers
Authors: Nzambi Aaron , Gomes Lana , Amanajás Cledinei , Silva Francisco , Oliveira Dênio
Published: June 2022

This experimental investigation presents results and a discussion on a series of four reinforced concrete pile caps with and without steel fibers, measuring 400 × 400 × 1000 mm3, which were tested under concentric loading. The study set the steel fiber and the inclined shear reinforcement as variables. The fiber volume fraction was 1.5%, and the concrete compressive strength was 25 MPa. The results showed a tendency to increase ductility and ultimate strength with the use of inclined shear reinforcement; the same behavior was observed with the addition of steel fibers, improving the performance of the tested pile caps. This study opens the possibility of designing slender pile caps, especially when associated with both analyzed parameters.
A novel near-infrared fluorescent probe based on triphenylamine derivatives for the rapid and sensitive detection of heparin
Authors: Liu Mingming , Cao Jian , Huang Cuiping , Zhang Meijuan , Li Yanan , Wang Chuanxiao
Published: June 2022

In this study, a positively charged near-infrared fluorescent probe (TPA-P+) was constructed by connecting a pyridine cation with triphenylamine and successfully used for the detection of heparin.
Near-room-temperature dielectric switch and thermal expansion anomaly in a new hybrid crystal: (Me2NH2)[CsFe(CN)5(NO)]
Authors: Li Qi-Yao , Li Mao-Fan , Chen Xiao-Xian , Gong Ya-Ping , Liu De-Xuan , Xu Wei-Jian , Zhang Wei-Xiong
Published: June 2022

A nitroprusside-based hybrid crystal featuring a double-layered inorganic framework encapsulating organic cations exhibits thermo-responsive switching behaviours on dielectric constant and biaxial expansivity.
Oxidation of HOSO˙ by O2 (3Σg−): a key reaction deciding the fate of HOSO˙ in the atmosphere
Authors: Rai Philips Kumar , Sarkar Saptarshi , Bandyopadhyay Biman , Kumar Pradeep
Published: June 2022

In the present work, we have studied the oxidation of HOSO˙ by O2 (3Σg−) molecules employing quantum chemical and kinetic calculations.
Copper and neocuproine catalysed synthesis of cinnamyl ether derivatives directly from secondary and tertiary cinnamyl alcohols
Authors: Yang Zhenjiao , Zhang Yongsheng , Lv Xingxian , Yang Yang , Jiang Chunhao , He Xiaoyan , Chen Guoliang , Huang Gang , Lu Xiuhong
Published: June 2022

A new method for the O-alkylation of secondary and tertiary cinnamyl alcohols with primary alcohols by employing CuSO4·5H2O and neocuproine as catalysts was developed, and PEG-modified secondary and tertiary cinnamyl alcohols can be achieved directly.
Correction: Precise measurement of selenium isotopes by HG-MC-ICPMS using a 76–78 double-spike
Authors: Pons Marie-Laure , Millet Marc-Alban , Nowell Geoff N. , Misra Sambuddha , Williams Helen M.
Published: June 2022

Correction for ‘Precise measurement of selenium isotopes by HG-MC-ICPMS using a 76–78 double-spike’ by Marie-Laure Pons et al., J. Anal. At. Spectrom., 2020, 35, 320–330, https://doi.org/10.1030/c9ja00331b.
Ring systems in natural products: structural diversity, physicochemical properties, and coverage by synthetic compounds
Authors: Chen Ya , Rosenkranz Cara , Hirte Steffen , Kirchmair Johannes
Published: June 2022

This cheminformatics study investigates the ring systems present in natural products and their coverage by ring systems observed in synthetic compounds.
Correction: Shape-controlled anisotropy of superparamagnetic micro-/nanohelices
Authors: Leshansky Alexander M. , Morozov Konstantin I. , Rubinstein Boris Y.
Published: June 2022

Correction for ‘Shape-controlled anisotropy of superparamagnetic micro-/nanohelices’ by Alexander M. Leshansky et al., Nanoscale, 2016, 8, 14127–14138, https://doi.org/10.1039/C6NR01803C.
Maternal Morbidity in the Second Stage of Labor: Analysis to Simulate the Clinical Choice
Authors: Little Sarah E. , Clapp Mark A. , Lassey Sarah , Bukowski Radek , Barth William H. , Robinson Julian
Published: June 2022

Objective The aim of the study is to analyze maternal morbidity in the second stage of labor in a manner that approximates clinical choice.

Study Design The study design comprises secondary analysis of the Consortium for Safe Labor, which included 228,688 deliveries at 19 hospitals between 2002 and 2008. We included the 107,675 women who were undergoing a trial of labor without a prior uterine scar or history of substance abuse, who reached the second stage, with a liveborn, nonanomalous, vertex, singleton, at term of at least 2,500 g. Maternal complications included postpartum fever, hemorrhage, blood transfusion, thrombosis, intensive care unit (ICU) admission, hysterectomy, and death. For maternal complications, we simulated the clinical choice by comparing operative vaginal or cesarean deliveries to continued expectant management at every hour in the second stage. For neonatal complications, we modeled the risk of severe neonatal complication by second stage duration for spontaneous vaginal deliveries only, adjusting for maternal demographics, comorbidities, and delivery hospital. Severe neonatal complications included death, asphyxia, hypoxic-ischemic encephalopathy (HIE), seizure, sepsis with prolonged stay, need for mechanical ventilation, and 5-minute Apgar score <4.

Results Maternal morbidity was higher with operative vaginal/cesarean delivery versus continued expectant management for every hour in the second stage, a difference that was statistically significant at hour 2 (18.4 vs. 14.7%; p <0.01). Overall, 951 (0.88%) deliveries were complicated by a severe neonatal complication. A second stage over 4 hours was associated with an adjusted odds of severe neonatal complication of 2.10 (95% confidence interval [CI]: 1.32–3.34) as compared with women who delivered in the first hour.

Conclusion There is a trade-off between maternal and neonatal morbidity in the second stage of labor. Serious neonatal complications rise throughout, however, there is no time at which maternal morbidity is improved with a cesarean or operative vaginal delivery. Strategies are needed to identify neonates at highest risk of complication for targeted intervention.

Key Points
Concept, design, and measurement methodology of a highly dynamic thin film dryer for experimental in situ drying manipulation
Authors: Schugmann Martin , Foerst Petra
Published: June 2022

This paper describes the technical setup and validation of a thin film drying device in which the conditions such as air temperature, relative humidity, and velocity can be controlled in the range of 20–200 °C, 0–1.5 m s−1, and vapor mass flows up to 1200 g min−1. For the first time, it is possible to perform in situ manipulation of the drying kinetic in a highly dynamic manner. The setup allows for a precise online determination of drying and rehydration kinetics; the recording of relevant process parameters such as air humidity, air and surface temperature; and the monitoring of optically observable material properties. The concept for rapid real-time changes in drying conditions is explained, and the constructive details are elucidated. Highly precise gravimetry by a proposed measurement methodology and simultaneously avoiding condensation during rapid parameter changes is accomplished. This is achieved by the combination of minimized thermal inertia of the system, air conditioning via carrier gas-free evaporation, and a highly responsive active insulation. The influence on the drying kinetics by temperature, humidity, and air velocity is shown with experiments on aqueous maltose solution, and the experimental precision is validated. The validation showed a high grade of accuracy regarding gravimetric determination with a maximum observed mass difference of 0.21% referring to the dried product. The dynamics of the setup under in situ changes in drying conditions is exemplified by further experiments. In addition, the presented setup for the first time enables the real time manipulation and observation of kinetically coupled processes such as crystallization behavior, morphology formation, or material degradation during drying. Therefore, it has important practical value for the development of efficient and energy-saving drying methods and products with specific, tailor-made properties.
Research on efficient and stable control of EUV-induced hydrogen plasma
Authors: Mao Qijun , Gong Xuepeng , Lu Qipeng , Song Yuan , Wang Dazhuang , Bai Yang , Ma Tianyu
Published: June 2022

We use the numerical model to study the control method for the ion sputter flux and energy at the surface of multilayer mirrors in hydrogen plasmas induced by extreme ultraviolet (EUV) radiation. This plasma is generated via photoionization by EUV photons with wavelengths at 13.5 nm and collision ionization by high-energy electrons. An electric field is formed by applying different bias voltages to the cylindrically symmetrical cavity and sample holder, which guides the transfer of charged particles and increases their energy. The evolution of pulsed EUV-induced plasma under the field is described by a two-dimension particle-in-cell model and the Monte Carlo simulation to represent collisions between charged particles and background molecules. The results show that the distribution of the electric field varies during the pulse and point out that the secondary electrons, which gain energy from the varying field and generate more plasma by collisions with hydrogen molecules, are crucial plasma sources in this scheme. We then propose a stable and efficient control method for EUV-induced hydrogen plasma by optimizing the cavity structure as an ellipsoid and treating the surface of the cavity in contact with the plasma.
Isochronous mass spectrometry in an electrostatic storage ring
Authors: Grieser Manfred , Schmidt Viviane C. , Blaum Klaus , Grussie Florian , von Hahn Robert , Kálosi Ábel , Kreckel Holger , Müll Damian , Novotný Oldřich , Nuesslein Felix , Wolf Andreas
Published: June 2022

For sensitive studies of molecular ions in electrostatic storage rings, the exact knowledge of the isobaric composition of stored beams from a variety of ion sources is essential. Conventional mass-filtering techniques are often inefficient to resolve the beam components. Here, we report the first isochronous mass spectrometry in an electrostatic storage ring, which offers a high mass resolution of Δm/m < 1 × 10−5 even for heavy molecular species with m > 100 u and uncooled ion beams. Mass contaminations can be resolved and identified at relative fractions down to 0.02%.
Electrical and thermal percolation in two-phase materials: A perspective
Authors: Forero-Sandoval I. Y. , Franco-Bacca A. P. , Cervantes-Álvarez F. , Gómez-Heredia C. L. , Ramírez-Rincón J. A. , Ordonez-Miranda J. , Alvarado-Gil J. J.
Published: June 2022

Electrical percolation in two-phase materials involves a very singular behavior, manifested as a huge change in the electrical conductivity, for a given volume or mass fraction of the phase with higher conductivity. In contrast, in the case of heat transfer, in two-phase composite systems, analogous percolative phenomena are far more elusive and have been rather difficult to observe in various physical systems. In this Perspective, we present a critical analysis of experimental results and the application of theoretical models aimed to study the effects of percolation phenomena on the thermal and electrical properties of two-phase materials. Our attention will be focused on composites made of high conductivity particles in a polymeric matrix. The effect of several factors, such as the geometrical and physical characteristics of fillers and their connectivity with the matrix, the proportion between the conductivity of filler and the matrix, as well as the crucial role of interfacial thermal resistance, is considered. In particular, the differences between the thermal and electrical thresholds and the physical and geometrical conditions that should be fulfilled to observe thermal percolation are discussed. Future trends, to be followed in the development of new materials, in order to enhance the thermal conductivity as well as in making the thermal percolative effects notable, based on including additional phases and 2D fillers, are also discussed.
Unified polarizable electrode models for open and closed circuits: Revisiting the effects of electrode polarization and different circuit conditions on electrode–electrolyte interfaces
Authors: Takahashi Ken , Nakano Hiroshi , Sato Hirofumi
Published: June 2022

A precise understanding of the interfacial structure and dynamics is essential for the optimal design of various electrochemical devices. Herein, we propose a method for classical molecular dynamics simulations to deal with electrochemical interfaces with polarizable electrodes under the open circuit condition. Less attention has been given to electrochemical circuit conditions in computation despite being often essential for a proper assessment, especially comparison between different models. The present method is based on the chemical potential equalization principle, as is a method developed previously to deal with systems under the closed circuit condition. These two methods can be interconverted through the Legendre transformation so that the difference in the circuit conditions can be compared on the same footing. Furthermore, the electrode polarization effect can be correctly studied by comparing the present method with conventional simulations with the electrodes represented by fixed charges, since both of the methods describe systems under the open circuit condition. The method is applied to a parallel-plate capacitor composed of platinum electrodes and an aqueous electrolyte solution. The electrode polarization effects have an impact on the interfacial structure of the electrolyte solution. We found that the difference in circuit conditions significantly affects the dynamics of the electrolyte solution. The electric field at the charged electrode surface is poorly screened by the nonequilibrium solution structure in the open circuit condition, which accelerates the motion of the electrolyte solution.
Investigation on discharge process and switching characteristics of a pseudospark switch in series with a magnetic switch
Authors: Shen Saikang , Yan Jiaqi , Sun Guoxiang , Ding Weidong
Published: June 2022

To reduce the commutation loss of the pseudospark switch, we connect a magnetic switch in series to the anode of the pseudospark switch. Herein, the typical discharge process and switching characteristics of a pseudospark switch in series with a magnetic switch are experimentally investigated at a different number of magnetic cores, gas pressures, and applied voltages. The results show that the addition of the magnetic switch extends the duration of the hollow cathode discharge of the pseudospark. Moreover, the rapid increase of the loop current and the fast decrease of the discharge voltage are separated, which is beneficial for reducing the commutation loss. With an increasing number of magnetic cores, the magnetic delay time increases and the commutation loss significantly decreases. However, the trigger delay time hardly changes since the magnetic switch does not affect the development of the pre-breakdown phase. At a fixed applied voltage, the trigger delay, magnetic delay time, and commutation loss decrease with increasing gas pressure. Furthermore, at a fixed gas pressure, the trigger delay of the pseudospark switch in series with a magnetic switch first decreases and then remains unchanged with increasing applied voltage, which is similar to that of a pseudospark switch without a magnetic switch because of the strong enough trigger injection. The magnetic delay time decreases and the commutation loss almost linearly increases with increasing applied voltage.
Evaluation of different particle-actuation modes in molecular dynamics and their impact on nanoscale flow behaviors
Authors: Guan Qingshan , Shan Baochao , Wang Runxi , Feng Guang , Guo Zhaoli
Published: June 2022

An accurate understanding of nanoscale gas transport mechanism is a fundamental research concern in many engineering applications, which remains as a research challenge currently. Two particle-actuation modes, namely, force-driven and pressure-driven methods, are evaluated and compared by molecular dynamics simulations of flows in nano-channels focusing on the characteristics of gas adsorption and slip velocity behaviors. The force-driven method may lead to unphysical properties when fluid inhomogeneities are significant since all fluid molecules are subjected to a same external force. By contrast, fluid molecules move forwards through the central part of the flow domain as a predominate pathway in a pressure-driven method. Results show that there is a significant difference between the two methods at smooth or small rough wall conditions, while the results tend to be consistent as roughness increases. The density distribution is uniform along the flow direction in force-driven cases, while adsorbed gas density increases in pressure-driven cases, leading to a smaller slip velocity near the outlet region. The effects of fluid wettability strength on solid surfaces and system temperature on gas adsorption/flow behaviors are also investigated and analyzed. This study is helpful for better understanding nanoscale gas dynamics and has many practical implications, such as the shale gas production.
Dynamics of cross-platform attention to retracted papers
Authors: Peng Hao , Romero Daniel M. , Horvát Emőke-Ágnes
Published: June 2022

Retracted papers often circulate widely on social media, digital news, and other websites before their official retraction. The spread of potentially inaccurate or misleading results from retracted papers can harm the scientific community and the public. Here, we quantify the amount and type of attention 3,851 retracted papers received over time in different online platforms. Comparing with a set of nonretracted control papers from the same journals with similar publication year, number of coauthors, and author impact, we show that retracted papers receive more attention after publication not only on social media but also, on heavily curated platforms, such as news outlets and knowledge repositories, amplifying the negative impact on the public. At the same time, we find that posts on Twitter tend to express more criticism about retracted than about control papers, suggesting that criticism-expressing tweets could contain factual information about problematic papers. Most importantly, around the time they are retracted, papers generate discussions that are primarily about the retraction incident rather than about research findings, showing that by this point, papers have exhausted attention to their results and highlighting the limited effect of retractions. Our findings reveal the extent to which retracted papers are discussed on different online platforms and identify at scale audience criticism toward them. In this context, we show that retraction is not an effective tool to reduce online attention to problematic papers.
Automated calibration of model-driven reconstructions in atom probe tomography
Authors: Fletcher Charles , Moody Michael P , Fleischmann Claudia , Dialameh Masoud , Porret Clement , Geiser Brian , Haley Daniel
Published: June 2022

Traditional reconstruction protocols in atom probe tomography frequently feature image distortions for multiphase materials, due to inaccurate geometric assumptions regarding specimen evolution. In this work, the authors’ outline a new reconstruction protocol capable of correcting for many of these distortions. This new method uses predictions from a previously developed physical model for specimen field evaporation. The application of this new model-driven approach to both an experimental semiconductor multilayer system and a fin field-effect transistor device (finFET) is considered. In both systems, a significant reduction in multiphase image distortions when using this new algorithm is clearly demonstrated. By being able to quantitatively compare model predictions with experiment, such a method could also be applied to testing and validating new developments in field evaporation theory.
Investigation of a vertical 2D/3D semiconductor heterostructure based on GaSe and Ga2O3
Authors: Sorifi Sahin , Kaushik Shuchi , Sheoran Hardhyan , Singh Rajendra
Published: June 2022

Mixed-dimensional heterostructures are emerging to be very promising for future electronic and optoelectronic applications. Here, we report on the fabrication and characterization of a 2D/3D vertical van der Waals p–n heterojunction based on p-type gallium selenide (GaSe) and n-type gallium oxide (

G

a

2

O

3

). Kelvin Probe Force Microscopic (KPFM) measurements have been conducted to estimate the difference in the surface potential values between GaSe and

G

a

2

O

3

, which is further used to find out the conduction band offset value at the GaSe/

G

a

2

O

3

hetero-interface to design the band diagrams. The current–voltage measurements on the device display a diode-like behavior which is attributed to the type-II band alignment, present at the p–n junction interface as per the electron affinities and bandgap values of GaSe and

G

a

2

O

3

. The device exhibits a high current rectification ratio of ∼2500 extracted at

±
5

V. The photoresponse properties of the heterostructure are also studied and the figure of merit parameters of the photodetector such as photoresponsivity and specific detectivity have been evaluated for the fabricated device. Since the GaSe/

G

a

2

O

3

heterojunction holds a great potential in the field of efficient optoelectronic devices, we believe our study could pave the way to designing innovative optoelectronic devices by integrating low-dimensional materials with conventional 3D semiconducting materials.
Fabrication and integration of functional stretchable circuit based on liquid metal
Authors: Pan Xudong , He Hu
Published: June 2022

A liquid metal patterning method and a fabrication process for liquid metal stretchable circuits are described. The initial resistance of the wire-electrode unit is only about 1.4 Ω, and the maximum applied strain is up to 260%. Static stretching and dynamic fatigue tests both reflect the excellent resistance stability. Two types of integrated packaging processes for liquid metal stretchable circuits, surface mount and embedded, are presented. The LED-wire unit manufactured by the embedded method can work normally under a strain of 260%. Through the integration process of surface mounting, the electronic devices are integrated onto the flexible substrate, and the flexible circuit system demonstration of a flash LED is realized. The circuit can work normally under 100% strain. The integration process for liquid metal based flexible electronics provides potential applications in flexible micro-systems.
Effects of Hypertension on the Incidence of Acute Coronary Syndrome and Severity of Coronary Artery Disease in Young Women
Authors: Liu Rui-fang , Xu Fang-xing , Liu Tong-ku , Zhou Yu-jie , Zhao Ying-xin , Yang Shi-wei , Yan Zhen-xian
Published: June 2022

Background

To investigate the effects of hypertension on the prevalence of acute coronary syndrome (ACS) and the severity of coronary artery disease in young women in northern China.

Methods

A retrospective analysis was performed on 840 young female patients (age <45 years old) underwent coronary angiography due to chest pain or chest discomfort between January 2007 and December 2016. The patients were divided into hypertension group (256 cases) and control group (584 cases). The risk factors and prevalence of ACS, and coronary stents implantation in the 2 groups were studied.

Results

The prevalence of ACS was higher in the hypertension group compared with the control group (80.9% vs. 36.5%, P < 0.05). The rates of hyperlipidemia (37.1% vs. 14.9%), hypercholesterolemia (8.6% vs. 3.4%), hyperuricemia (18.4% vs. 7.2%), and hyperhomocysteinemia (10.9% vs. 3.9%) were all significantly higher in the hypertensives compared with controls (all P < 0.05). The hypertension group had higher rates of overweight (63.7% vs. 29.5%), family history of early coronary heart disease (15.2% vs. 5.5%), smoking (5.5% vs. 4.3%), menopause (4.7% vs. 1.7%), and type 2 diabetes (24.2% vs. 8.9%) compared with the control group (all P < 0.05). Double branch lesions of coronary artery in hypertension and control groups were 14.1% and 5.7%, respectively (P < 0.05). Further, hypertensive patients with ACS had higher number (1.67 ± 1.05 vs. 1.41 ± 0.85) and longer (24.44 ± 6.97 vs. 22.85 ± 7.80 mm) stents implantation than the control group (P < 0.05).

Conclusions

Hypertension is the main risk factor of ACS in young women in northern China. Young women with hypertension have more risk factors for atherosclerotic cardiovascular disease.
Fitness Costs ofpfhrp2andpfhrp3Deletions Underlying Diagnostic Evasion in Malaria Parasites
Authors: Nair Shalini , Li Xue , Nkhoma Standwell C , Anderson Tim
Published: June 2022

Background

Rapid diagnostic tests based on detection of histidine-rich proteins (HRPs) are widely used for malaria diagnosis, but parasites carrying pfhrp deletions can evade detection and are increasing in frequency in some countries. Models aim to predict conditions under which pfhrp2 and/or pfhrp3 deletions will increase, but a key parameter—the fitness cost of deletions—is unknown.

Methods

We removed pfhrp2 and/or pfhrp3 from a Malawian parasite clone using gene editing approaches) and measured fitness costs by conducting pairwise competition experiments.

Results

We observed significant fitness costs of 0.087 ± 0.008 (1 standard error) per asexual cycle for pfhrp2 deletion and 0.113 ± 0.008 for the pfhrp2/3 double deletion, relative to the unedited progenitor parasite. Selection against deletions is strong and comparable to that resulting from drug resistance mutations.

Conclusions

Prior modeling suggested that diagnostic selection may drive increased frequency of pfhrp deletions only when fitness costs are mild. Our experiments show that costs of pfhrp deletions are higher than these thresholds, but modeling and empirical results can be reconciled if the duration of infection is short. These results may inform future modeling to understand why pfhrp2/3 deletions are increasing in some locations (Ethiopia and Eritrea) but not in others (Mekong region).
Characteristics of stripes-pattern radio-emission sources
Authors: Alielden Khaled
Published: June 2022

An investigation of the generation mechanism for stripes-pattern radio spectra is important for an understanding of the dynamics of non-thermal electrons in several astronomical objects, including the Sun, Jupiter, and the Crab Pulsar. A new analytical study is carried out to identify the plasma characteristics of fiber- and zebra-pattern emission sources without an underlying density or magnetic model. The analysis demonstrates that the source region of the stripes emission is located underneath the reconnection point, where the ratio s of the instability growth rate to the electron gyrofrequency ωc does not equal unity; that is, s = k⊥v⊥/ωc ≠ 1. When |s| < 1, the plasma condition of the source region becomes k⊥v⊥ < ωp < ωc, where ωp is the plasma frequency, and the emission source is likely to produce a fiber radio burst. For |s| > 1, the plasma condition of the source region is ωc < ωp < k⊥v⊥, and the emission source is likely to produce zebra-pattern emission. This indicates that the magnetic field in the source region of zebra-pattern radio emission is weak and it is relatively high in the source region of fiber-pattern emission. An approach is applied to estimate the plasma parameters of a zebra-pattern emission source observed on 2011 June 21. The behaviour of the blasted medium, which is produced by magnetic reconnection, is investigated. The results show that the blasted medium propagates isothermally as a sausage-like wave for a short time during the emission. The study discusses the conditions for producing different types of striped radio emission and provides a simple computational approach that could be useful in a number of astronomical contexts.
New globular cluster candidates in the M81 group
Authors: Pan Jiaming , Bell Eric F , Smercina Adam , Price Paul , Slater Colin T , Bailin Jeremy , de Jong Roelof S , D’Souza Richard , Jang In Sung , Monachesi Antonela
Published: June 2022

The study of outer halo globular cluster (GC) populations can give insight into galaxy merging, GC accretion, and the origin of GCs. We use archival Subaru Hyper Suprime-Cam (HSC) data in concert with space-based GALEX, IRAC, and Gaia EDR3 data to select candidate GCs in the outer halo of the M81 group for confirmation and future study. We use a small sample of previously discovered GCs to tune our selection criteria, finding that bright already-known GCs in the M81 group have sizes that are typically slightly larger than the Subaru PSF in our fields. In the optical bands, GCs appear to have colours that are only slightly different from stars. The inclusion of archival IRAC data yields dramatic improvements in colour separation, as the long wavelength baseline aids somewhat in the separation from stars and clearly separates GCs from many compact background galaxies. We show that some previously spectroscopically identified GCs in the M81 group are instead foreground stars or background galaxies. GCs close to M82 have radial velocities, suggesting that they fell into the M81 group along with M82. The overall M81 GC luminosity function is similar to the Milky Way and M31. M81’s outer halo GCs are similar to the Milky Way in their metallicities and numbers, and much less numerous than M31’s more metal-rich outer halo GC population. These properties reflect differences in the three galaxies’ merger histories, highlighting the possibility of using outer halo GCs to trace merger history in larger samples of galaxies.
Lessons from the Magellanic System and its modeling
Authors: Wang Jianling , Hammer Francois , Yang Yanbin
Published: June 2022

The prominent Magellanic Stream that dominates the H i sky provides a tantalizing number of observations that potentially constrains the Magellanic Clouds and the Milky Way (MW) outskirts. Here we show that the ‘ram-pressure plus collision’ model naturally explain these properties, and is able to predict some of the most recent observations made after the model was made. These include the complexity of the stellar populations in the Magellanic Bridge, for which kinematics, ages, and distances are well measured, and the Northern Tidal Arm, for which the model predicts its formation from the MW tidal forces. It appears that this over-constrained model provides a good path to investigate the Stream properties. This contrasts with tidal models that reproduce only half of the Stream’s main properties, in particular a tidal tail cannot reproduce the observed inter-twisted filaments, and its gas content is not sufficiently massive to provide the large amount of H i and H ii gas associated to the Stream. Despite the efforts made to reproduce the large amounts of gas brought by the Clouds, it seems that no viable solution for the tidal model could be foreseen. Since the ‘ram-pressure plus collision’ model has not succeeded for a Large Magellanic Cloud mass above 2 × 1010 M⊙, we conjecture that a low mass is required to form the Stream.
Statistics of BY Draconis chromospheric variable stars
Authors: Chahal Deepak , de Grijs Richard , Kamath Devika , Chen Xiaodian
Published: June 2022

We present an extensive catalogue of BY Draconis (BY Dra)-type variables and their stellar parameters. BY Dra are main-sequence FGKM-type stars. They exhibit inhomogeneous starspots and bright faculae in their photospheres. These features are caused by stellar magnetic fields, which are carried along with the stellar disc through rotation and which produce gradual modulations in their light curves (LCs). Our main objective is to characterize the properties of BY Dra variables over a wide range of stellar masses, temperatures, and rotation periods. A recent study categorized 84 697 BY Dra variables from Data Release 2 of the Zwicky Transient Facility based on their LCs. We have collected additional photometric data from multiple surveys and performed broad-band spectral energy distribution fits to estimate stellar parameters. We found that more than half of our sample objects are of K spectral type, covering an extensive range of stellar parameters in the low-mass regime (0.1–1.3 M⊙). Compared with previous studies, most of the sources in our catalogue are rapid rotators, and so most of them must be young stars for which a spin-down has not yet occurred. We subdivided our catalogue based on convection zone depth and found that the photospheric activity index, Sph, is lower for higher effective temperatures, i.e. for thinner convective envelopes. We observe a broad range of photospheric magnetic activity for different spectral classes owing to the presence of stellar populations of different ages. We found a higher magnetically active fraction for K- than M-type stars.
Effect of the cosmological transition to metal-enriched star formation on the hydrogen 21-cm signal
Authors: Magg Mattis , Reis Itamar , Fialkov Anastasia , Barkana Rennan , Klessen Ralf S , Glover Simon C O , Chen Li-Hsin , Hartwig Tilman , Schauer Anna T P
Published: June 2022

Mapping cosmic dawn with 21-cm tomography offers an exciting new window into the era of primordial star formation. However, self-consistent implementation of both the process of star formation and the related 21-cm signal is challenging, due to the multiscale nature of the problem. In this study, we develop a flexible semi-analytical model to follow the formation of the first stars and the process of gradual transition from primordial to metal-enriched star formation. For this transition, we use different scenarios with varying time-delays (or recovery times) between the first supernovae and the formation of the second generation of stars. We use recovery times between 10 and 100 Myr and find that these delays have a strong impact on the redshift at which the transition to metal-enriched star formation occurs. We then explore the effect of this transition on the 21-cm signal and find that the recovery time has a distinctive imprint in the signal. Together with an improved understanding of how this time-delay relates to the properties of Population III stars, future 21-cm observations can give independent constraints on the earliest epoch of star formation. As the transition away from the primordial star formation is expected to occur at high redshifts, here we ignore the impact of X-ray and ionizing radiation, focusing on the effect of Ly α photons on the 21-cm signal.
Tax Advantages and Imperfect Competition in Auctions for Municipal Bonds
Authors: Garrett Daniel , Ordin Andrey , Roberts James W , Suárez Serrato Juan Carlos
Published: June 2022

We study the interaction between tax advantages for municipal bonds and the market structure of auctions for these bonds. We show that this interaction can limit a bidder’s ability to extract information rents and is a crucial determinant of state and local governments’ borrowing costs. Reduced-form estimates show that increasing the tax advantage by 3 pp lowers mean borrowing costs by 9–10$\%$. We estimate a structural auction model to measure markups and to illustrate and quantify how the interaction between tax policy and bidder strategic behaviour determines the impact of tax advantages on municipal borrowing costs. We use the estimated model to evaluate the efficiency of Obama and Trump administration policies that limit the tax advantage for municipal bonds. Because reductions in the tax advantage inflate bidder markups and depress competition, the resulting increase in municipal borrowing costs more than offsets the tax savings to the government. Finally, we use the model to analyse a recent non-tax regulation that affects entry into municipal bond auctions.
DYNAMIC OF BEDSIDE ULTRASOUND VENOUS AND PULMONARY CONGESTION ASSESSMENT IN PATIENTS WITH ARTERIAL HYPERTENSION AND DECOMPENSATED HEART FAILURE
Authors: Aslanova Rena , Andriamanohery Robinson , Abdulloev Dzhakhongir , Montoya F. Cabello , Lapshin Artem , Efimova Viktoriia , Safarova Ayten , Kobalava Zhanna
Published: June 2022

Objective:

arterial hypertension is a major pandemic in the modern world and is a common cause of heart failure. Identification of pulmonary and venous congestion is relevant in patients with arterial hypertension(AH) and decompensated heart failure (DHF)

Design and method:

to assess the severity and dynamics of venous congestion (VC) by VExUS (including the study of the inferior vena cava (IVC), porto-hepatic and renal blood flow), and pulmonary congestion (PC) by LUS (with B-lines assessment according to 8-zone method) in patients with AH and DHF at admission to hospital and at discharge. The PC was defined as the sum of B-lines of more than 5 (6–15, 16–30 and> 30 - light, moderate and severe pulmonary congestion, respectively). Standard examinations and assessment of VC and LUS were performed in 52 patients with AH and DHF in the first 48 hours after admission and at discharge (men 48%, age 70 ± 11 years (M ± SD), atrial fibrillation 60%, diabetes 40%, chronic anemia 27%, left ventricle ejection fraction (LVEF) 50 [40; 57] %, EF < 40% - 29%, NTproBNP 1421 [754; 2024] pg/ml (Me; IQR)). To assess the severity of clinical symptoms and signs of congestion, the composite congestion score (CCS) was assessed: 0 - no congestion; 1–2-moderate; > = 3 severe congestion.

Results:

at admission, 27% of patients had moderate congestion according to CCS scale, 65% had severe congestion. In 31%, 13% and 17% of patients, mild, moderate and severe VC was revealed, respectively. Mild, moderate and severe PC was detected in 21%, 27% and 48% of patients, respectively. Congestion was present in 50% of patients at discharge according to CCS scale (moderate-42%, severe-8%). VC persisted in 38% of patients:mild in 20%, moderate–in 12%, severe–in 6% of cases. At discharge, PC was still present in 44% of patients. 15% of patients had mild PC, 20%-moderate and 9%-severe. VC and PC significantly correlated with NT-proBNP (r = 0.3,p = 0.03 and r = 0.41,p = 0.003,respectively) and with each other (r = 0.35,p = 0.01)

Conclusions:

Correlations between venous congestion assessed by VEXUS protocol and PC by LUS with NtproBNP in patients with AH and DHF were revealed
Multiple Organ Dysfunction in Older Major Trauma Critical Care Patients
Authors: Cole Elaine , Aylwin Chris , Christie Robert , Dillane Bebhinn , Farrah Helen , Hopkins Phillip , Ryan Chris , Woodgate Adam , Brohi Karim
Published: June 2022

Objective:

The objective was to explore the characteristics and outcomes of multiple organ dysfunction syndrome (MODS) in older trauma patients.

Background:

Severely injured older people present an increasing challenge for trauma systems. Recovery for those who require critical care may be complicated by MODS. In older trauma patients, MODS may not be predictable based on chronological age alone and factors associated with its development and resolution are unclear.

Methods:

Consecutive adult patients (aged ≥16 years) admitted to 4 level 1 major trauma center critical care units were enrolled and reviewed daily until discharge or death. MODS was defined by a daily total sequential organ failure assessment score of >5.

Results:

One thousand three hundred sixteen patients were enrolled over 18 months and one-third (434) were aged ≥65 years. Incidence of MODS was high for both age groups (<65 years: 64%, ≥65 years: 70%). There were few differences in severity, patterns, and duration of MODS between cohorts, except for older traumatic brain injury (TBI) patients who experienced a prolonged course of MODS recovery (TBI: 9 days vs no TBI: 5 days, P < 0.01). Frailty rather than chronological age had a strong association with MODS development (odds ratio [OR], 6.9; 95% confidence intervals [CI], 3.0–12.4; P < 0.001) and MODS mortality (OR, 2.1; 95% CI, 1.31–3.38; P = 0.02). Critical care resource utilization was not increased in older patients, but MODS had a substantial impact on mortality (<65 years: 17%; ≥65 years: 28%). The majority of older patients who did not develop MODS survived and had favorable discharge outcomes (home discharge ≥65 years NoMODS: 50% vs MODS: 15%; P < 0.01).

Conclusions:

Frailty rather than chronological age appears to drive MODS development, recovery, and outcome in older cohorts. Early identification of frailty after trauma may help to predict MODS and plan care in older trauma.
Concurrent Mental Illness and Financial Barriers to Mental Health Care Among a Nationally Representative Sample of Orthopaedic Trauma Survivors
Authors: Jella Tarun K. , Cwalina Thomas B. , Vallier Heather A.
Published: June 2022

Objectives:

To understand prevalence and factors associated with concurrent mental illness and financial barriers to mental health care after orthopaedic trauma.

Design:

This is a retrospective, cross-sectional study.

Setting:

Interview-based survey was conducted across representative sample of 30,000 US households.

Patients/Participants:

The study included 2,309 survey respondents reporting a fracture over the past 3 months, between 2004 and 2017.

Intervention:

Screening for financial barriers to mental health care.

Main Outcome Measurements:

Prevalence and factors associated with concurrent mental illness and financial barriers to mental health care based on sociodemographic and injury characteristics were the main outcome measurements.

Results:

Of the 2309 orthopaedic trauma survivors included in our analysis, 203 patients [7.8%, 95% confidence interval (CI): 6.4%–9.2%] were determined to experience severe mental illness, of whom 54 (25.3%, 95% CI: 18.0%–32.6%) and 86 (40.9%, 95% CI: 31.5%–50.2%) reported financial barriers to counseling and pharmacotherapy, respectively. Factors associated with concurrent severe mental illness and cost barriers to care were 45 to 64 years of age [adjusted odds ratios (AOR) 5.1, 95% CI: 1.7–15, P = 0.004], income below 200% of the Federal Poverty Threshold (AOR 2.5, 95% CI: 1.2–5.3, P = 0.012), and unemployment at the time of injury (AOR 3.9, 95% CI: 1.4–11, P = 0.009).

Conclusions:

Approximately one half of orthopaedic trauma survivors with severe mental illness face financial barriers to some form of mental health services. Younger, minority, and low socioeconomic status patients are most affected. These data suggest the presence of postdiagnosis disparities in mental health access that may be improved through direct provision and subsidization of integrated mental health support services for high-risk populations.

Level of Evidence:

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.