bluuebunny/crossref_metadata_2025 huggingface dataset:
Peptide VSAK maintains tissue glucose uptake and attenuates pro-inflammatory responses caused by LPS in an experimental model of the systemic inflammatory response syndrome: a PET study
Authors: Luna-Reyes Ismael , Pérez-Hernández Eréndira G. , Delgado-Coello Blanca , Ávila-Rodríguez Miguel Ángel , Mas-Oliva Jaime
Published: July 2021

The present investigation using Positron Emission Tomography shows how peptide VSAK can reduce the detrimental effects produced by lipopolysaccharides in Dutch dwarf rabbits, used to develop the Systemic Inflammatory Response Syndrome (SIRS). Animals concomitantly treated with lipopolysaccharides (LPS) and peptide VSAK show important protection in the loss of radiolabeled-glucose uptake observed in diverse organs when animals are exclusively treated with LPS. Treatment with peptide VSAK prevented the onset of changes in serum levels of glucose and insulin associated with the establishment of SIRS and the insulin resistance-like syndrome. Treatment with peptide VSAK also allowed an important attenuation in the circulating levels of pro-inflammatory molecules in LPS-treated animals. As a whole, our data suggest that peptide VSAK might be considered as a candidate in the development of new therapeutic possibilities focused on mitigating the harmful effects produced by lipopolysaccharides during the course of SIRS.
A sequence variant in the diacylglycerol O-acyltransferase 2 gene influences palmitoleic acid content in pig muscle
Authors: Solé Emma , Ros-Freixedes Roger , Tor Marc , Pena Ramona N. , Estany Joan
Published: July 2021

The bulk of body fat in mammals is in the form of triacylglycerol. Diacylglycerol O-acyltransferase 2 (DGAT2) catalyses the terminal step in triacylglycerol synthesis. The proximity of DGAT2 with stearoyl-CoA desaturase (SCD) in the endoplasmic reticulum may facilitate provision of de novo SCD-mediated fatty acids as substrate for DGAT2. Here, we first searched for sequence variants in the DGAT2 gene to then validate their effect on fat content and fatty acid composition in muscle, subcutaneous fat and liver of 1129 Duroc pigs. A single nucleotide polymorphism in exon 9 (ss7315407085 G > A) was selected as a tag variant for the 33 sequence variants identified in the DGAT2 region. The DGAT2-G allele increased DGAT2 expression in muscle and had a positive impact on muscular C14 and C16 fatty acids at the expense of C18 fatty acids. Although there was no evidence for an interaction of DGAT2 with functional SCD genotypes, pigs carrying the DGAT2-G allele had proportionally more palmitoleic acid relative to palmitic acid. Our findings indicate that DGAT2 preferentially uptakes shorter rather than longer-chain fatty acids as substrate, especially if they are monounsaturated, and confirm that fatty acid metabolism in pigs is subjected to subtle tissue-specific genetic regulatory mechanisms.
Development of a system to support warfarin dose decisions using deep neural networks
Authors: Lee Heemoon , Kim Hyun Joo , Chang Hyoung Woo , Kim Dong Jung , Mo Jonghoon , Kim Ji-Eon
Published: July 2021

The first aim of this study was to develop a prothrombin time international normalized ratio (PT INR) prediction model. The second aim was to develop a warfarin maintenance dose decision support system as a precise warfarin dosing platform. Data of 19,719 inpatients from three institutions was analyzed. The PT INR prediction algorithm included dense and recurrent neural networks, and was designed to predict the 5th-day PT INR from data of days 1–4. Data from patients in one hospital (n = 22,314) was used to train the algorithm which was tested with the datasets from the other two hospitals (n = 12,673). The performance of 5th-day PT INR prediction was compared with 2000 predictions made by 10 expert physicians. A generator of individualized warfarin dose-PT INR tables which simulated the repeated administration of varying doses of warfarin was developed based on the prediction model. The algorithm outperformed humans with accuracy terms of within ± 0.3 of the actual value (machine learning algorithm: 10,650/12,673 cases (84.0%), expert physicians: 1647/2000 cases (81.9%), P = 0.014). In the individualized warfarin dose-PT INR tables generated by the algorithm, the 8th-day PT INR predictions were within 0.3 of actual value in 450/842 cases (53.4%). An artificial intelligence-based warfarin dosing algorithm using a recurrent neural network outperformed expert physicians in predicting future PT INRs. An individualized warfarin dose-PT INR table generator which was constructed based on this algorithm was acceptable.
Kinetic characterisation and inhibitor sensitivity of Candida albicans and Candida auris recombinant AOX expressed in a self-assembled proteoliposome system
Authors: Copsey Alice C. , Barsottini Mario R. O. , May Benjamin , Xu Fei , Albury Mary S. , Young Luke , Moore Anthony L.
Published: July 2021

Candidemia caused by Candida spp. is a serious threat in hospital settings being a major cause of acquired infection and death and a possible contributor to Covid-19 mortality. Candidemia incidence has been rising worldwide following increases in fungicide-resistant pathogens highlighting the need for more effective antifungal agents with novel modes of action. The membrane-bound enzyme alternative oxidase (AOX) promotes fungicide resistance and is absent in humans making it a desirable therapeutic target. However, the lipophilic nature of the AOX substrate (ubiquinol-10) has hindered its kinetic characterisation in physiologically-relevant conditions. Here, we present the purification and expression of recombinant AOXs from C. albicans and C. auris in a self-assembled proteoliposome (PL) system. Kinetic parameters (Km and Vmax) with respect to ubiquinol-10 have been determined. The PL system has also been employed in dose–response assays with novel AOX inhibitors. Such information is critical for the future development of novel treatments for Candidemia.
Enhancing the weighted voting ensemble algorithm for tuberculosis predictive diagnosis
Authors: Osamor Victor Chukwudi , Okezie Adaugo Fiona
Published: July 2021

Tuberculosis has the most considerable death rate among diseases caused by a single micro-organism type. The disease is a significant issue for most third-world countries due to poor diagnosis and treatment potentials. Early diagnosis of tuberculosis is the most effective way of managing the disease in patients to reduce the mortality rate of the infection. Despite several methods that exist in diagnosing tuberculosis, the limitations ranging from the cost in carrying out the test to the time taken to obtain the results have hindered early diagnosis of the disease. This work aims to develop a predictive model that would help in the diagnosis of TB using an extended weighted voting ensemble method. The method used to carry out this research involved analyzing tuberculosis gene expression data obtained from GEO (Transcript Expression Omnibus) database and developing a classification model to aid tuberculosis diagnosis. A classifier combination of Naïve Bayes (NB), and Support Vector Machine (SVM) was used to develop the classification model. The weighted voting ensemble technique was used to improve the classification model's performance by combining the classification results of the single classifier and selecting the group with the highest vote based on the weights given to the single classifiers. Experimental analysis indicates a performance accuracy of the enhanced ensemble classifier as 0.95, which showed a better performance than the single classifiers, which had 0.92, and 0.87 obtained from SVM and NB, respectively. The developed model can also assist health practitioners in the timely diagnosis of tuberculosis, which would reduce the mortality rate caused by the disease, especially in developing countries.
Survival analysis of patients with primary breast duct carcinoma and lung adenocarcinoma: a population-based study from SEER
Authors: Lv Fengyuan , Cheng Mingliang , Jiang Liang , Zhao Xiaoping
Published: July 2021

The appeal to enroll patients with primary breast and lung cancer in clinical trials is increasing, but survival of these two primary cancers remains to be elucidated. This study analyzed the prognosis of primary breast duct carcinoma with subsequent lung adenocarcinoma (BCLA) and primary breast duct carcinoma with prior lung adenocarcinoma (LABC). Cohorts of 3,515 patients with BCLA and 654 patients with LABC were identified from the Surveillance, Epidemiology, and End Results database. Patients were classified into simultaneous two primary cancer (sTPC), metachronous two primary cancer (mTPC1), or mTPC2 groups when the interval times between breast and lung cancer were within 6 months, between 7 and 60 months, or over 60 months, respectively. The propensity score matching program (PSM) was applied to determine the survival of BCLA/LABC relative to single breast/lung cancer. Cox proportional hazard regression model and competing risk modes were performed to identify confounders associated with all-cause and cancer-specific death, respectively. Survival of patients with LABC/BCLA relative to single breast/lung cancer was accessed via median survival time. The survival of patients with BCLA/LABC was generally poor compared with the survival of those with single breast cancer. The PSM-estimated HR in the sTPC group with BCLA and in the mTPC1 and mTPC2 groups with LABC were 0.75 (95% CI 0.62–0.90), 0.52 (95% CI 0.27–0.98), and 0.36 (95% CI 0.20–0.65), respectively, whereas the SHRs were 0.80 (95% CI 0.66–0.97), 0.68 (95% CI 0.34–1.34), and 0.46 (95% CI 0.27–0.80), respectively, compared with those in the single lung cancer group. By contrast, the survival rates of the remaining patients did not differ. The median survival times since secondary malignancy were 42, 23, and 20 months in the sTPC, mTPC1, and mTPC2 groups with BCLA, respectively, and 18, 60, and 180 months in those with LABC, respectively. For patients with BCLA, the adjusted Cox regression suggested incidences of all-cause deaths in mTPC1group were statically higher than those in sTPC group, whereas the incidences of all-cause and cancer-specific death in the mTPC1 and mTPC2 groups were statistically lower than those in the sTPC group. The prognosis of patients with breast cancer and subsequent lung cancer of over 18 months was not significantly different than that of single lung cancer, which supported the profound appeal to increase the involvement of these two primary cancers in potential beneficial clinical trials. For patients with lung cancer and prior breast cancer of within 6 months and subsequent breast cancer of over 18 months, prognosis was improved relative to single lung cancer. Therefore, additional attention is needed to eliminate the potential bias may when these patients are recruited in the clinical trials.
Exploiting RNA thermometer-driven molecular bioprocess control as a concept for heterologous rhamnolipid production
Authors: Noll Philipp , Treinen Chantal , Müller Sven , Lilge Lars , Hausmann Rudolf , Henkel Marius
Published: July 2021

A key challenge to advance the efficiency of bioprocesses is the uncoupling of biomass from product formation, as biomass represents a by-product that is in most cases difficult to recycle efficiently. Using the example of rhamnolipid biosurfactants, a temperature-sensitive heterologous production system under translation control of a fourU RNA thermometer fromSalmonellawas established to allow separating phases of preferred growth from product formation. Rhamnolipids as bulk chemicals represent a model system for future processes of industrial biotechnology and are therefore tied to the efficiency requirements in competition with the chemical industry. Experimental data confirms function of the RNA thermometer and suggests a major effect of temperature on specific rhamnolipid production rates with an increase of the average production rate by a factor of 11 between 25 and 38 °C, while the major part of this increase is attributable to the regulatory effect of the RNA thermometer rather than an unspecific overall increase in bacterial metabolism. The production capacity of the developed temperature sensitive-system was evaluated in a simple batch process driven by a temperature switch. Product formation was evaluated by efficiency parameters and yields, confirming increased product formation rates and product-per-biomass yields compared to a high titer heterologous rhamnolipid production process from literature.
Solar UV-B/A radiation is highly effective in inactivating SARS-CoV-2
Authors: Nicastro Fabrizio , Sironi Giorgia , Antonello Elio , Bianco Andrea , Biasin Mara , Brucato John R. , Ermolli Ilaria , Pareschi Giovanni , Salvati Marta , Tozzi Paolo , Trabattoni Daria , Clerici Mario
Published: July 2021

Solar UV-C photons do not reach Earth’s surface, but are known to be endowed with germicidal properties that are also effective on viruses. The effect of softer UV-B and UV-A photons, which copiously reach the Earth’s surface, on viruses are instead little studied, particularly on single-stranded RNA viruses. Here we combine our measurements of the action spectrum of Covid-19 in response to UV light, Solar irradiation measurements on Earth during the SARS-CoV-2 pandemics, worldwide recorded Covid-19 mortality data and our “Solar-Pump” diffusive model of epidemics to show that (a) UV-B/A photons have a powerful virucidal effect on the single-stranded RNA virus Covid-19 and that (b) the Solar radiation that reaches temperate regions of the Earth at noon during summers, is sufficient to inactivate 63% of virions in open-space concentrations (1.5 × 103 TCID50/mL, higher than typical aerosol) in less than 2 min. We conclude that the characteristic seasonality imprint displayed world-wide by the SARS-Cov-2 mortality time-series throughout the diffusion of the outbreak (with temperate regions showing clear seasonal trends and equatorial regions suffering, on average, a systematically lower mortality), might have been efficiently set by the different intensity of UV-B/A Solar radiation hitting different Earth’s locations at different times of the year. Our results suggest that Solar UV-B/A play an important role in planning strategies of confinement of the epidemics, which should be worked out and set up during spring/summer months and fully implemented during low-solar-irradiation periods.
Genomic heterogeneity affects the response to Daylight Saving Time
Authors: Tyler Jonathan , Fang Yu , Goldstein Cathy , Forger Daniel , Sen Srijan , Burmeister Margit
Published: July 2021

Circadian clocks control the timing of many physiological events in the 24-h day. When individuals undergo an abrupt external shift (e.g., change in work schedule or travel across multiple time zones), circadian clocks become misaligned with the new time and may take several days to adjust. Chronic circadian misalignment, e.g., as a result of shift work, has been shown to lead to several physical and mental health problems. Despite the serious health implications of circadian misalignment, relatively little is known about how genetic variation affects an individual’s ability to entrain to abrupt external changes. Accordingly, we used the one-hour advance from the onset of daylight saving time (DST) as a natural experiment to comprehensively study how individual heterogeneity affects the shift of sleep/wake cycles in response to an abrupt external time change. We found that individuals genetically predisposed to a morning tendency adjusted to the advance in a few days, while genetically predisposed evening-inclined individuals had not shifted. Observing differential effects by genetic disposition after a one-hour advance underscores the importance of heterogeneity in adaptation to external schedule shifts. These genetic differences may affect how individuals adjust to jet lag or shift work as well.
Predicting critical state after COVID-19 diagnosis: model development using a large US electronic health record dataset
Authors: Rinderknecht Mike D. , Klopfenstein Yannick
Published: July 2021

As the COVID-19 pandemic is challenging healthcare systems worldwide, early identification of patients with a high risk of complication is crucial. We present a prognostic model predicting critical state within 28 days following COVID-19 diagnosis trained on data from US electronic health records (IBM Explorys), including demographics, comorbidities, symptoms, and hospitalization. Out of 15753 COVID-19 patients, 2050 went into critical state or deceased. Non-random train-test splits by time were repeated 100 times and led to a ROC AUC of 0.861 [0.838, 0.883] and a precision-recall AUC of 0.434 [0.414, 0.485] (median and interquartile range). The interpretability analysis confirmed evidence on major risk factors (e.g., older age, higher BMI, male gender, diabetes, and cardiovascular disease) in an efficient way compared to clinical studies, demonstrating the model validity. Such personalized predictions could enable fine-graded risk stratification for optimized care management.
Bromodomain-containing protein BRPF1 is a therapeutic target for liver cancer
Authors: Cheng Carol Lai-Hung , Tsang Felice Hoi-Ching , Wei Lai , Chen Mengnuo , Chin Don Wai-Ching , Shen Jialing , Law Cheuk-Ting , Lee Derek , Wong Carmen Chak-Lui , Ng Irene Oi-Lin , Wong Chun-Ming
Published: July 2021

Epigenetic deregulation plays an essential role in hepatocellular carcinoma (HCC) progression. Bromodomains are epigenetic “readers” of histone acetylation. Recently, bromodomain inhibitors have exhibited promising therapeutic potential for cancer treatment. Using transcriptome sequencing, we identifiedBRPF1(bromodomain and PHD finger containing 1) as the most significantly upregulated gene among the 43 bromodomain-containing genes in human HCC. BRPF1 upregulation was significantly associated with poor patient survival. Gene ablation or pharmacological inactivation of BRPF1 significantly attenuated HCC cell growth in vitro and in vivo. BRPF1 was involved in cell cycle progression, senescence and cancer stemness. Transcriptome sequencing revealed that BRPF1 is a master regulator controlling the expression of multiple key oncogenes, includingE2F2andEZH2. We demonstrated that BRPF1 activated E2F2 and EZH2 expression by facilitating promoter H3K14 acetylation through MOZ/MORF complex. In conclusion, BRPF1 is frequently upregulated in human HCCs. Targeting BRPF1 may be an approach for HCC treatment.
Hypoxia-specific anti-RAGE exosomes for nose-to-brain delivery of anti-miR-181a oligonucleotide in an ischemic stroke model
Authors: Kim Minkyung , Lee Youngki , Lee Minhyung
Published: July 2021

An exosome linked to RAGE-binding-peptide was developed as a hypoxia-specific carrier for nose-to-brain delivery of anti-microRNA oligonucleotide for ischemic stroke therapy.
A versatile pH-responsive peptide based dynamic biointerface for tracking bacteria killing and infection resistance
Authors: Wang Fenghua , Sha Xiangyu , Wu Rongrong , Zhang Liwei , Song Xiaolu , Tian Xiaohua , Pan Guoqing , Liu Lei
Published: July 2021

A versatile pH-responsive peptide based biointerface based on pH-responsive peptide assembling and disassembling was used for killing bacteria by releasing peptides in slightly acidic infectious environment and also showing the infection resistance.
Inhibition of protein synthesis through RNA-based tandem G-quadruplex formation
Authors: Hagihara Masaki
Published: July 2021

Tandem G-quadruplexes formed in the coding region of mRNA stands effectively inhibited in vitro protein synthesis.
Catalytic oxidation of methane to methanol over Cu-CHA with molecular oxygen
Authors: Hirayama Airi , Tsuchimura Yuka , Yoshida Hiroshi , Machida Masato , Nishimura Shun , Kato Kazuo , Takahashi Keisuke , Ohyama Junya
Published: July 2021

Catalytic production of CH3OH in a CH4–O2–H2O flow reaction is improved using Cu-CHA having improved redox property involved in the C–H activation of CH4.
Synthesis and [*C]CO-labelling of (C,N) gem-dimethylbenzylamine–palladium complexes for potential applications in positron emission tomography
Authors: Cormier Morgan , Tabey Alexis , Christine Thifanie , Audrain Hélène , Fouquet Eric , Hermange Philippe
Published: July 2021

13C- and 11C-labelled conjugates were produced in one step upon carbonylation of homogeneous or heterogeneous arylpalladium complexes synthesised by mild C–H activation of gem-dimethylbenzylamine derivatives.
Construction of novel polyethylenimine-g-C3N4/BiOCl heterojunctions for the efficient photocatalytic degradation of nitro explosives
Authors: Yan Jing , Song Xiaomin , Jin Bo , Peng Rufang
Published: July 2021

Novel polyethylenimine-g-C3N4/BiOCl (PEI-CN/BC) heterojunctions displayed excellent photocatalytic activity on the degradation of nitro explosives.
Polydopamine assists the continuous growth of zeolitic imidazolate framework-8 on electrospun polyacrylonitrile fibers as efficient adsorbents for the improved removal of Cr(vi)
Authors: Yang Xu , Zhou Yuhong , Sun Zhaojie , Yang Chunhui , Tang Dongyan
Published: July 2021

PDA coating assists the growth of ZIF-8 particles on PAN fibers to fabricate composite ZIF-8@PDA/PAN fibers as efficient adsorbents for Cr(vi) removal.
Multifunctional nanozyme for multimodal imaging-guided enhanced sonodynamic therapy by regulating the tumor microenvironment
Authors: Liu Shuling , Zhang Wei , Chen Qiaoqi , Hou Jingxin , Wang Junrui , Zhong Yixin , Wang Xingyue , Jiang Weixi , Ran Haitao , Guo Dajing
Published: July 2021

Sonodynamic therapy (SDT) is a highly promising approach for cancer therapy, but its efficacy is severely hampered by the low specificity of sonosensitizers and the unfavorable characteristics of the tumor microenvironment (TME).
ZIF/Co-C3N4 with enhanced electrocatalytic reduction of carbon dioxide activity by the photoactivation process
Authors: Qi Huihui , Zhou Yunjie , Li Yi , Liao Fan , Wang Zhenzhen , Wang Xiao , Huang Hui , Shao Mingwang , Liu Yang , Kang Zhenhui
Published: July 2021

The photoactivation process promotes the electrocatalytic carbon dioxide reaction on the interface of ZIF/Co-C3N4.
Facial synthesis of two-dimensional In2S3/Ti3C2Tx heterostructures with boosted photoactivity for the hydrogenation of nitroaromatic compounds
Authors: Zhu Yisong , Xie Guanshun , Li Guohao , Song Fei , Yu Changqiang , Wu Zhenjun , Xie Xiuqiang , Zhang Nan
Published: July 2021

In this work, Ti3C2Tx (MXene) acts as the platform for directing the growth of 2D In2S3 nanoflakes, thereby generating 2D In2S3/Ti3C2Tx heterostructures, which exhibited boosted photocatalytic activities compared to bare In2S3.
A tubular electrode assembly reactor for enhanced electrochemical wastewater treatment with a Magnéli-phase titanium suboxide (M-TiSO) anode and in situ utilization
Authors: Liang Jiabin , You Shijie , Yuan Yixing , Yuan Yuan
Published: July 2021

A stainless steel pipe (SSP) was used as a cathode. A tubular Magnéli-phase titanium suboxide (M-TiSO) anode was posited in the center. A spiral static mixer was used to process intensification.
A model of modified meta-iodobenzylguanidine conjugated gold nanoparticles for neuroblastoma treatment
Authors: Saimuang Kween , Suttisintong Khomson , Kaewchangwat Narongpol , Thanayupong Eknarin , Wongngam Yodsathorn , Charoenphun Putthiporn , Wanotayan Rujira , Elaissari Abdelhamid , Hongeng Suradej , Polpanich Duangporn , Jangpatarapongsa Kulachart
Published: July 2021

127I-modified mIBG was successfully synthesized and grafted covalently to the surface of carboxylated PEG-GNPs. The particles were not toxic to the normal fibroblast cells while specifically internalized into neuroblastoma cells line via NET.
Nanofibrous spherical cage mimicking a ball of pearl necklaces for super capture of heavy metal ions
Authors: Jung Youngkyun , Choi Ung Su , Ko Young Gun
Published: July 2021

Innovatively designed nanofibrous spherical adsorbents allow the precipitation of heavy metal ions, confine the precipitate within the adsorbents, and achieve a remarkable decrease in the pressure drop.
Hydrogen sulfide removal from natural gas using membrane technology: a review
Authors: Ma Yulei , Guo Hongfang , Selyanchyn Roman , Wang Bangda , Deng Liyuan , Dai Zhongde , Jiang Xia
Published: July 2021

In this review, the H2S/CH4 separation properties of polymer membranes are presented and a new upper bound is proposed. In view of the existing problems and development prospects of various membranes, the corresponding opinions and advices are given.
Ultrafast-charging quasi-solid-state fiber-shaped zinc-ion hybrid supercapacitors with superior flexibility
Authors: Pu Jie , Cao Qinghe , Gao Yong , Yang Jie , Cai Dongming , Chen Xing , Tang Xiaowan , Fu Gangwen , Pan Zhenghui , Guan Cao
Published: July 2021

3D N-CNT nanoarrays can effectively facilitate stress release and maintain their structural stability. The assembled quasi-solid-state FZHSC exhibits both good flexibility and superior electrochemical performance.
Water-passivated ZnMgO nanoparticles for blue quantum dot light-emitting diodes
Authors: Guo Yue , Liu Bochen , Chen Zhao , Song Weidong , Tian Naifan , Wu Wenhai , Fan Xiaokun , Zhan Yunfeng , Meng Fanyuan , Zeng Qingguang , Wong Wai-Yeung
Published: July 2021

The defects on the surface of ZnMgO are passivated by adding trace water. The blue QLED made by these water-passivated ZnMgO nanoparticles exhibits a superior performance.
Impact of moisture absorption on the resistive switching characteristics of a polyethylene oxide-based atomic switch
Authors: Krishnan Karthik , Gubicza Agnes , Aono Masakazu , Terabe Kazuya , Valov Ilia , Tsuruoka Tohru
Published: July 2021

Effect of moisture absorption on the resistive switching, redox reactions, and ion transport is investigated for a polyethylene oxide-based atomic switch.
Transceiver design for MU‐SIMO FSO communication over correlated lognormal channels
Authors: Yan Ruo‐Lin , Zhang Jian , Chen Ru‐Han , Si‐Ma Ling‐Han
Published: July 2021

In this paper, with the assumption of only channel statistics information available at the receivers, a novel concept of multiplicative uniquely decomposable constellations is proposed for multi‐user single‐input multiple‐output (MU‐SIMO) FSO systems in weak atmospheric turbulence, which is modeled by spatially dependent lognormal fading channels. The design enables the fast decoding at the users' sides and meanwhile allows flexibility in assigning each user's ordering to meet different priority needs. Simulation results show that our proposed design has a significant performance improvement over the TDMA scheme at the same rates.
Design and measurement of a novel metal‐only wideband magneto‐electric dipole antenna using asymmetrical structure
Authors: Wang Min , Mo Yuxin , Luo Wei , Yang Huifeng , Chen Zhengchuan
Published: July 2021

A novel metal‐only wideband magneto‐electric dipole antenna is designed and measured in this letter. The antenna consists of two rectangular patches etched with asymmetrical slots as electric dipole, two folded patches as magneto‐dipole, trident‐shaped feeding structure and side‐slotted ground, large metallic ground. The electric dipole is horizontally placed on both sides of the feeding structure, and two folded patches are assembled vertically on the small ground. Two symmetrically sided slots are etched on the small ground to reduce the profile and a trident‐shaped feeding strip is employed to widen the bandwidth, while a lower ground with a large size is designed to suppress the radiation in the backward direction. Finally, the antenna prototype is fabricated and measured. The measured results show that −10 dB impedance bandwidth is achieved up to 75.9% at 2.7 GHz from 2.0 to 4.1 GHz. At 2.7 GHz, the measured peak gain is 9.0 dBi.
Impact of size-dependent grain temperature on gas-grain chemistry in protoplanetary disks: The case of low-mass star disks
Authors: Gavino S. , Dutrey A. , Wakelam V. , Guilloteau S. , Kobus J. , Wolf S. , Iqbal W. , Di Folco E. , Chapillon E. , Piétu V.
Published: July 2021

Context. Grain surface chemistry is fundamental to the composition of protoplanetary disks around young stars.

Aims. The temperature of grains depends on their size. We evaluate the impact of this temperature dependence on the disk chemistry.

Methods. We modeled a moderately massive disk with 16 different grain sizes. We used the 3D Monte Carlo POLARIS code to calculate the dust grain temperatures and the local uv flux. We modeled the chemistry using the three-phase astrochemical code NAUTILUS. Photo processes were handled using frequency-dependent cross sections and a new method to account for self and mutual shielding. The multi-grain model outputs are compared to those of single-grain size models (0.1 μm); there are two different assumptions for their equivalent temperature.

Results. We find that the Langmuir-Hinshelwood mechanism at equilibrium temperature is not efficient to form H2 at 3–4 scale heights (H), and we adopt a parametric fit to a stochastic method to model H2 formation instead. We find the molecular layer composition (1–3 H) to depend on the amount of remaining H atoms. Differences in molecular surface densities between single and multi-grain models are mostly due to what occurs above 1.5 H. At 100 au, models with colder grains produce H2O and CH4 ices in the midplane, and those with warmer grains produce more CO2 ices; both of these allow for an efficient depletion of C and O as soon as CO sticks on grain surfaces. Complex organic molecules production is enhanced by the presence of warmer grains in the multi-grain models. Using a single-grain model mimicking grain growth and dust settling fails to reproduce the complexity of gas-grain chemistry.

Conclusions. Chemical models with a single-grain size are sensitive to the adopted grain temperature and cannot account for all expected effects. A spatial spread of the snowlines is expected to result from the ranges in grain temperature. The amplitude of the effects depends on the dust disk mass.
Plasma densities, flow, and solar EUV flux at comet 67P
Authors: Johansson F. L. , Eriksson A. I. , Vigren E. , Bucciantini L. , Henri P. , Nilsson H. , Bergman S. , Edberg N. J. T. , Stenberg Wieser G. , Odelstad E.
Published: July 2021

Context.During its two-year mission at comet 67P, Rosetta nearly continuously monitored the inner coma plasma environment for gas production rates varying over three orders of magnitude, at distances to the nucleus ranging from a few to a few hundred kilometres. To achieve the best possible measurements, cross-calibration of the plasma instruments is needed.

Aims.Our goal is to provide a consistent plasma density dataset for the full mission, while in the process providing a statistical characterisation of the plasma in the inner coma and its evolution.

Methods.We constructed physical models for two different methods to cross-calibrate the spacecraft potential and the ion current as measured by the Rosetta Langmuir probes (LAP) to the electron density as measured by the Mutual Impedance Probe (MIP). We also described the methods used to estimate spacecraft potential, and validated the results with the Ion Composition Analyser (ICA).

Results.We retrieve a continuous plasma density dataset for the entire cometary mission with a much improved dynamical range compared to any plasma instrument alone and, at times, improve the temporal resolution from 0.24−0.74 Hz to 57.8 Hz. The physical model also yields, at a three-hour time resolution, ion flow speeds and a proxy for the solar EUV flux from the photoemission from the Langmuir probes.

Conclusions.We report on two independent mission-wide estimates of the ion flow speed that are consistent with the bulk H2O+ion velocities as measured by the ICA. We find the ion flow to consistently be much faster than the neutral gas over the entire mission, lending further evidence that the ions are collisionally decoupled from the neutrals in the coma. Measurements of ion speeds from Rosetta are therefore not consistent with the assumptions made in previously published plasma density models of the comet 67P’s ionosphere at the start and end of the mission. Also, the measured EUV flux is perfectly consistent with independently derived values previously published from LAP and lends support for the conclusions drawn regarding an attenuation of solar EUV from a distant nanograin dust population, when the comet activity was high. The new density dataset is consistent with the existing MIP density dataset, but it facilitates plasma analysis on much shorter timescales, and it also covers long time periods where densities were too low to be measured by MIP.
The BINGO project
Authors: Zhang Jiajun , Motta Pablo , Novaes Camila P. , Abdalla Filipe B. , Costa Andre A. , Wang Bin , Zhu Zhenghao , Shan Chenxi , Xu Haiguang , Abdalla Elcio , Barosi Luciano , Brito Francisco A. , Queiroz Amilcar , Villela Thyrso , Wuensche Carlos A. , Ferreira Elisa G. M. , Fornazier Karin S. F. , Marins Alessandro , Santos Larissa , Vargas dos Santos Marcelo , Landim Ricardo G. , Liccardo Vincenzo
Published: July 2021

Context.BINGO (Baryon Acoustic Oscillations from Integrated Neutral Gas Observations) is a radio telescope designed to survey from 980 MHz to 1260 MHz, observe the neutral hydrogen (H I) 21 cm line, and detect the baryon acoustic oscillation signal with the intensity mapping technique. Here we present our method for generating mock maps of the 21 cm intensity mapping signal that cover the BINGO frequency range and related test results.

Aims.We would like to employN-body simulations to generate mock 21 cm intensity maps for BINGO and study the information contained in 21 cm intensity mapping observations about structure formation, H Idistribution and H Imass-halo mass relation.

Methods.We fit an H Imass-halo mass relation from the ELUCID semianalytical galaxy catalog and applied it to the Horizen Run 4 halo catalog to generate the 21 cm mock map, which is called HOD. We also applied the abundance-matching method and matched the Horizen Run 4 galaxy catalog with the H Imass function measured from ALFALFA, to generate the 21 cm mock map, which is called HAM.

Results.We studied the angular power spectrum of the mock maps and the corresponding pixel histogram. The comparison of two different mock map generation methods (HOD and HAM) is presented. We provide the fitting formula of ΩHi, H Ibias, and the lognormal fitting parameter of the maps, which can be used to generate similar maps. We discuss the possibility of measuring ΩHiand H Ibias by comparing the angular power spectrum of the mock maps and the theoretical calculation. We also discuss the redshift space distortion effect, the nonlinear effect, and the bin size effect in the mock map.

Conclusions.By comparing the angular power spectrum measured from two different types of mock maps and the theoretical calculation, we find that the theoretical calculation can only fit the mock result at large scales. At small scales, neither the linear calculation nor the halofit nonlinear calculation can provide an accurate fitting, which reflects our poor understanding of the nonlinear distribution of H Iand its scale-dependent bias. We have found that the bias is highly sensitive to the method of populating H Iin halos, which also means that we can place constraints on the H Idistribution in halos by observing 21 cm intensity mapping. We also illustrate that only with thin frequency bins (such as 2 MHz), we can discriminate the Finger-of-God effect. All of our investigations using mocks provide useful guidance for our expectation of BINGO experiments and other 21 cm intensity mapping experiments.
Which Milky Way masses are consistent with the slightly declining 5–25 kpc rotation curve?
Authors: Jiao Y. , Hammer F. , Wang J. L. , Yang Y. B.
Published: July 2021

Context. Discoveries of extended rotation curves have suggested that spiral galaxy halos contain dark matter. This has led to many studies that estimated the total mass of the Galaxy, mostly using the Navarro, Frenk, and White (NFW) density profile.

Aims. We determine the effect that the choice of the dark matter profile has on the predicted values of extrapolated total masses.

Methods. We considered a recently reported Milky Way (MW) rotation curve, first because of its unprecedented accuracy, and second because the Galactic disk appears to be least affected by past major mergers that have fully reshaped the initial disk.

Results. We find that the use of an NFW profile (or its generalized form, gNFW) to calculate the dark-matter contribution to the MW rotation curve generates apparently inconsistent results such as an increase in baryonic mass that leads to an increase in dark matter mass. Furthermore, we find that NFW and gNFW profiles narrow the total mass range, leading to a possible methodological bias particularly against low MW masses. Using the Einasto profile, which is better suited to represent cold dark matter halos, we finally found that the slightly decreasing rotation curve of the MW favors a total mass that can be as low as 2.6 × 1011 M⊙, disregarding any other dynamical tracers farther out in the MW. This is inconsistent with values higher than 18 × 1011 M⊙ for any type of cold dark matter halo profiles under the assumption that stars and gas do not affect the predicted dark matter distribution in the MW.

Conclusions. This methodological paper encourages the use of the Einasto profile to characterize rotation curves with the aim of evaluating their total masses.
ORion Alma New GEneration Survey (ORANGES)
Authors: Bouvier M. , López-Sepulcre A. , Ceccarelli C. , Sakai N. , Yamamoto S. , Yang Y.-L.
Published: July 2021

Context.The spectral energy distribution (SED) in the millimetre to centimetre range is an extremely useful tool for characterising the dust in protostellar envelopes as well as free-free emission from the protostar and outflow. Actually, the evolutionary status of solar-type protostars is often based on their SED in the near-infrared to millimetre range. In addition, the presence or absence of free-free emission can be considered an indicator of the source evolutionary stage (Class 0/I versus Class II/III). While many studies have been carried out towards low- and high-mass protostars, little exists so far about solar-type protostars in high-mass star-forming regions, which are likely to be representatives of the conditions where the Solar System was born.

Aims.In this work, we focus on the embedded solar-type protostars in the Orion Molecular Cloud (OMC) 2 and 3 filaments, which are bounded by nearby HII regions and which are, therefore, potentially affected by the high-UV illumination of the nearby OB stars. We use various dust parameters to understand whether the small-scale structure (≤1000 au) and the evolutionary status of these solar-type protostars are affected by the nearby HII regions, as is the case for the large-scale (≤104au) gas chemical composition.

Methods.We used the Atacama Large (sub-)Millimeter Array (ALMA) in the 1.3 mm band (246.2 GHz) to image the continuum of 16 young (Class 0/I) OMC-2/3 solar-type protostars, with an angular resolution of 0.25″ (100 au). We completed our data with archival data from the ALMA and VLA VANDAM survey of Orion Protostars at 333 and 32.9 GHz, respectively, to construct the dust SED and extract the dust temperature, the dust emissivity spectral index, the envelope plus disk mass of the sources and to assess whether free-free emission is contaminating their dust SED in the centimetre range.

Results.From the millimetre to centimetre range dust SED, we found low dust emissivity spectral indexes (β< 1) for the majority of our source sample and free-free emission towards only 5 of the 16 sample sources. We were also able to confirm or correct the evolutionary status of the source sample reported in the literature. Finally, we did not find any dependence of the source dust parameters on their location in the OMC-2/3 filament.

Conclusions.Our results show that the small-scale dust properties of the embedded OMC-2/3 protostars are not affected by the high-UV illumination from the nearby HII regions and that the formation of protostars likely takes place simultaneously throughout the filament.
The MUSE-Wide survey: Three-dimensional clustering analysis of Lyman-αemitters at 3.3 <z< 6
Authors: Herrero Alonso Y. , Krumpe M. , Wisotzki L. , Miyaji T. , Garel T. , Schmidt K. B. , Diener C. , Urrutia T. , Kerutt J. , Herenz E. C. , Schaye J. , Pezzulli G. , Maseda M. V. , Boogaard L. , Richard J.
Published: July 2021

We present an analysis of the spatial clustering of 695 Lyα-emitting galaxies (LAEs) in the MUSE-Wide survey. All objects have spectroscopically confirmed redshifts in the range 3.3 < z < 6. We employed the K-estimator, an alternative clustering statistic, adapted and optimized for our sample. We also explore the standard two-point correlation function approach, which is however less suited for a pencil-beam survey such as ours. The results from both approaches are consistent. We parametrize the clustering properties in two ways, (i) following the standard approach of modelling the clustering signal with a power law (PL), and (ii) adopting a halo occupation distribution (HOD) model of the two-halo term. Using the K-estimator and applying HOD modelling, we infer a large-scale bias ofbHOD= 2.80−0.38+0.38at a median redshift of the number of galaxy pairs ⟨zpair⟩ ≃ 3.82, while the best-fit power-law analysis givesbPL= 3.03−0.52+1.51(r0= 3.60−0.90+3.10comovingh−1Mpc andγ= 1.30−0.45+0.36). The implied typical dark matter halo (DMH) mass is log(MDMH/[h−1M⊙]) = 11.34−0.27+0.23(adoptingb = bHODand assumingσ8 = 0.8). We study possible dependencies of the clustering signal on object properties by bisecting the sample into disjoint subsets, considering Lyαluminosity, UV absolute magnitude, Lyαequivalent width, and redshift as variables. We find no evidence for a strong dependence on the latter three variables but detect a suggestive trend of more luminous Lyαemitters clustering more strongly (thus residing in more massive DMHs) than their lower Lyαluminosity counterparts. We also compare our results to mock LAE catalogs based on a semi-analytic model of galaxy formation and find a stronger clustering signal than in our observed sample, driven by spikes in the simulatedz-distributions. By adopting a galaxy-conserving model we estimate that the Lyα-bright galaxies in the MUSE-Wide survey will typically evolve into galaxies hosted by halos of log(MDMH/[h−1 M⊙]) ≈ 13.5 at redshift zero, suggesting that we observe the ancestors of present-day galaxy groups.
Inverse potential problems in divergence form for measures in the plane
Authors: Baratchart Laurent , Villalobos Guillén Cristóbal , Hardin Douglas P.
Published: July 2021

We study inverse potential problems with source term the divergence of some unknown (ℝ3-valued) measure supported in a plane;e.g., inverse magnetization problems for thin plates. We investigate methods for recovering a magnetizationμby penalizing the measure-theoretic total variation norm ∥μ∥TV, and appealing to the decomposition of divergence-free measures in the plane as superpositions of unit tangent vector fields on rectifiable Jordan curves. In particular, we prove for magnetizations supported in a plane thatTV-regularization schemes always have a unique minimizer, even in the presence of noise. It is further shown thatTV-norm minimization (among magnetizations generating the same field) uniquely recovers planar magnetizations in the following two cases: (i) when the magnetization is carried by a collection of sufficiently separated line segments and a set that is purely 1-unrectifiable; (ii) when a superset of the support is tree-like. We note that such magnetizations can be recoveredvia TV-regularization schemes in the zero noise limit by taking the regularization parameter to zero. This suggests definitions of sparsity in the present infinite dimensional context, that generate results akin to compressed sensing.
Dorsopathy in urban public transport drivers in relation to occupational risks and workloads
Authors: Mihăilă Delia , Iordache Raluca Maria , Petreanu Viorica
Published: July 2021

Drivers in urban public transport are exposed to specific risks and workloads with both somatic and psychological effects on their health. The most common somatic disorders are musculoskeletal diseases (MSDs), especially those of the spine, and some of them can be occupational diseases. The present paper represents a sequence from an ample study that has followed the effects of this professional activity on work aptitude and workers’ state of health and then has established prevention measures, respectively measures for reduction of identified risk factors. An ergonomic, complex and multidimensional methodology has been used. The health state analysis has been performed through a prevalence, cross-sectional study on three cohorts (bus, tram, trolleybus drivers). In all groups, a high percentage of spinal pathology has been found, especially lumbosacral. The highest percentage of dorsopathies has been registered in the group of the trolleybus drivers (48%), followed by the tram (43%) and the bus (42%). In all three cohorts, a significant percentage in disc herniation in the age group 36-45 years old has been found, which can indicate premature wear. The identification of occupational risk factors has allowed for the establishment of a set of prevention / reduction measures.
Notions regarding the design of suction systems for industrial ventilation
Authors: Gherghe Ion , Cioclea Doru , Rădoi Florin , Matei Adrian , Drăgoescu Răzvan
Published: July 2021

Air flow in ducts is one of the basic processes of ventilation and air conditioning. Knowledge of this phenomenon and the laws according to it is indispensable for drawing up the sizing calculations of the duct networks, for determining the energy needed to move the air as well as for determining the aerodynamic parameters related to the ventilation ducts. Industrial buildings include large spaces with various sources of releases of harmful substances. Type of these sources and their location depends on the technological process in each section or room.The main role of industrial ventilation systems is to provide a continuous source of fresh air supply from the outside, to keep the temperature and humidity at comfortable levels, to maintain an adequate supply of oxygen in the work area, to control concentrations of hazardous explosive and / or toxic gases in the air and at work, to remove unwanted odors from a particular area and to remove and dilute airborne contaminants. The paper presents the design of exhaust systems, the calculation of suction ventilation systems and the choice of ducts with higher aerodynamic parameters in the choice of fans, using nomograms.
Swelling properties of clays, a major risk factor for the infrastructure projects
Authors: Stãnciucu Mihaela , Terteleac Alexandra
Published: July 2021

Swelling and shrinking properties refers to significant positive or negative variations of volumes due to absorbtion or dessication of water in fine soils under natural or anthropic regime of moisture. These physical phenomena are worldwide spread and had important engineering consequences with associates cost of damages of several billion annually in all climate areas. In spite of the fact that these geotechnical properties are studied for more than eight decades, the particularities of these peculiar relations between water, mineral composition and geomechanical behavior are still unrevealed entirely. In Romania, swell/shrink soils are reported in all regions at different depths, but rarely related to geotechnical engineering accidents such as slope slides or road failures. This work presents some obvious relations between the hydrogeological structure, the presence of “large swell/shrink soils”, their mineralogical composition and geomechanical properties and the ubiquitous landslides on Peri Carpathians Hills. Large infrastructure projects offer the opportunities to put into evidence the swelling properties of Upper Pliocene-Lower Pleistocene deposits, which supports the Holocene alluvial deposits of Argeş River. Analyzed samples allow us to define some basic correlations between plasticity index, colloidal fraction, dry density, swelling pressures or free swelling and mineralogical composition.