bluuebunny/crossref_metadata_2025 huggingface dataset:
The Metabolic Response to a Low Amino Acid Diet is Independent of Diet-Induced Shifts in the Composition of the Gut Microbiome
Authors: Pak Heidi H. , Cummings Nicole E. , Green Cara L. , Brinkman Jacqueline A. , Yu Deyang , Tomasiewicz Jay L. , Yang Shany E. , Boyle Colin , Konon Elizabeth N. , Ong Irene M. , Lamming Dudley W.
Published: January 2019

Obesity and type 2 diabetes are increasing in prevalence around the world, and there is a clear need for new and effective strategies to promote metabolic health. A low protein (LP) diet improves metabolic health in both rodents and humans, but the mechanisms that underlie this effect remain unknown. The gut microbiome has recently emerged as a potent regulator of host metabolism and the response to diet. Here, we demonstrate that a LP diet significantly alters the taxonomic composition of the gut microbiome at the phylum level, altering the relative abundance of Actinobacteria, Bacteroidetes, and Firmicutes. Transcriptional profiling suggested that any impact of the microbiome on liver metabolism was likely independent of the microbiome-farnesoid X receptor (FXR) axis. We therefore tested the ability of a LP diet to improve metabolic health following antibiotic ablation of the gut microbiota. We found that a LP diet promotes leanness, increases energy expenditure, and improves glycemic control equally well in mice treated with antibiotics as in untreated control animals. Our results demonstrate that the beneficial effects of a LP diet on glucose homeostasis, energy balance, and body composition are unlikely to be mediated by diet-induced changes in the taxonomic composition of the gut microbiome.
The Dice measure of cubic hesitant fuzzy sets and its initial evaluation method of benign prostatic hyperplasia symptoms
Authors: Fu Jing , Ye Jun , Cui Wenhua
Published: January 2019

In order to give the initial evaluation of benign prostatic hyperplasia (BPH) symptoms regarding a patient, physician usually performs the clinical inquiry of the patient, whereas his/her responses may contain hesitant fuzzy and uncertain information. However, existing evaluation/diagnosis approaches of BPH symptoms cannot cope with the hybrid problem of both hesitant and uncertain responses of patients. Furthermore, existing evaluation approaches may lose some useful responses (e.g. hesitant fuzzy information) so as to result in the unreasonable or indeterminate evaluation/diagnosis in the evaluation process of patients. To overcome this insufficiency, this study firstly introduces the concept of a cubic hesitant fuzzy set (CHFS) based on combining uncertain/interval-valued fuzzy information with hesitant fuzzy information so as to express the hybrid fuzzy information and proposes the Dice measure between CHFSs based on the extension method of the least common multiple cardinality/number (LCMC) for the hesitant fuzzy sets in CHFS. Then, the initial evaluation approach of BPH symptoms is developed by using the Dice measure of CHFSs. Lastly, the assessment results of six BPH patients are presented as the clinical actual cases to indicate the applicability and effectiveness of the developed assessment approach in CHFS setting. The comparison with existing common evaluation methods shows that the developed evaluation/diagnosis method is superior to the existing common evaluation methods in the evaluation/diagnosis process of the clinical actual cases.
MultiLink Analysis: Brain Network Comparison via Sparse Connectivity Analysis
Authors: Crimi Alessandro , Giancardo Luca , Sambataro Fabio , Gozzi Alessandro , Murino Vittorio , Sona Diego
Published: January 2019

The analysis of the brain from a connectivity perspective is revealing novel insights into brain structure and function. Discovery is, however, hindered by the lack of prior knowledge used to make hypotheses. Additionally, exploratory data analysis is made complex by the high dimensionality of data. Indeed, to assess the effect of pathological states on brain networks, neuroscientists are often required to evaluate experimental effects in case-control studies, with hundreds of thousands of connections. In this paper, we propose an approach to identify the multivariate relationships in brain connections that characterize two distinct groups, hence permitting the investigators to immediately discover the subnetworks that contain information about the differences between experimental groups. In particular, we are interested in data discovery related to connectomics, where the connections that characterize differences between two groups of subjects are found. Nevertheless, those connections do not necessarily maximize the accuracy in classification since this does not guarantee reliable interpretation of specific differences between groups. In practice, our method exploits recent machine learning techniques employing sparsity to deal with weighted networks describing the whole-brain macro connectivity. We evaluated our technique on functional and structural connectomes from human and murine brain data. In our experiments, we automatically identified disease-relevant connections in datasets with supervised and unsupervised anatomy-driven parcellation approaches and by using high-dimensional datasets.
Construction of 3D Si@Ti@TiN thin film arrays for aqueous symmetric supercapacitors
Authors: Wei Binbin , Liang Hanfeng , Qi Zhengbing , Zhang Dongfang , Shen Hao , Hu Wenshen , Wang Zhoucheng
Published: January 2019

This work presents a general strategy to produce 3D array electrode structures based on transition metal nitrides that otherwise are much more difficult to directly prepare by conventional routes and further to enhance their electrochemical performance for supercapacitors.
Alkynylation of graphene via the Sonogashira C–C cross-coupling reaction on fluorographene
Authors: Chronopoulos Demetrios D. , Medved’ Miroslav , Błoński Piotr , Nováček Zdeněk , Jakubec Petr , Tomanec Ondřej , Bakandritsos Aristides , Novotná Veronika , Zbořil Radek , Otyepka Michal
Published: January 2019

We report successful grafting of alkynyl groups onto graphene via the Sonogashira reaction between fluorographene and terminal alkynes.
Improving properties of energetic coordination polymers through structural modulation from 1D to 3D without changes of ligands or metal nodes
Authors: Li Xin , Sun Qi , Lu Ming , Lin Qiuhan
Published: January 2019

Two energetic coordination polymers, Pb2(AOT)2·7(H2O) (1) (AOT: 5,5′-azo-bis(1-oxidotetrazonate)) and Pb2(AOT)O·3(H2O) (2), were prepared at different temperatures and pressures.
Effect of polyhedron deformation on the 5d energy level of Ce3+in lanthanide aluminum perovskites
Authors: Song Zhen , Liu Quanlin
Published: January 2019

This paper shows how polyhedron deformation has an effect on the Ce3+energy levels in ideal polyhedrons with regard to real polyhedrons in lanthanide aluminum perovskites.
Tuning the shape anisotropy of loosely bound colloid-like ionic clusters in solution
Authors: Eisermann Jana , Hinderberger Dariush
Published: January 2019

We characterize the influence of the ionic ratio on the dynamic self-assembly process involving a macrocyclic tetraimidazolium molecular box and small dianionic salts into highly defined, colloid-like ionic clusters in solution, called ionoids.
Geographical location specific composition of cultured microbiota and Lactobacillus occurrence in human breast milk in China
Authors: Ding Mengfan , Qi Ce , Yang Zhengyu , Jiang Shan , Bi Ye , Lai Jianqiang , Sun Jin
Published: January 2019

Composition of microbiota in human breast milk in China was highly geographical location specific and can be classified into Enterococcus, Streptococcus and Staphylococcus dominant group, respectively. The occurrence rate of Lactobacillus in Northwest and North China is high. Lactobacillus reuteri and Lactobacillus gasseri in Tibetan samples, Gansu Lintan, were the highest.
A microfluidic platform integrated with field-effect transistors for enumeration of circulating tumor cells
Authors: Chen Yi-Hong , Pulikkathodi Anil Kumar , Ma Yu-Dong , Wang Yu-Lin , Lee Gwo-Bin
Published: January 2019

A new integrated microfluidic system was developed for automatic detection and enumeration of CTCs with field-effect transistors (FETs).
Current and future biomarkers for risk-stratification and treatment personalisation in multiple myeloma
Authors: Lê Giao N. , Bones Jonathan , Coyne Mark , Bazou Despina , Dowling Paul , O’Gorman Peter , Larkin Anne-Marie
Published: January 2019

Genomic, proteomic, and glycomic platforms are utilised to improve biomarkers for prognostication and prediction of treatment response in multiple myeloma.
A urea-modified tryptophan basedin situreducing and stabilizing agent for the fabrication of gold nanoparticles as a Suzuki–Miyaura cross-coupling catalyst in water
Authors: Sasmal Supriya , Debnath Mintu , Nandi Sujay Kumar , Haldar Debasish
Published: January 2019

Urea modified tryptophan has been used as anin situreducing and stabilizing agent for the fabrication of gold nanoparticles and the gold nanoparticles efficiently catalyzed the Suzuki–Miyaura cross-coupling reaction in water.
Copper(ii) complexes with 4-acyl pyrazolone derivatives and diimine coligands: synthesis, structural characterization, DNA binding and antitumor activity
Authors: Wang Jun , Xu Guan-Cheng , Zhang Yan-Ping , Luo Hua-Ying , Li Jin-Yao , Zhang Li , Jia Dian-Zeng
Published: January 2019

Three copper complexes of 4-acyl pyrazolone derivatives were constructed. Their DNA binding and cancer cell inhibitory activities were investigated.
N/Ti3+-codoped triphasic TiO2/g-C3N4 heterojunctions as visible-light photocatalysts for the degradation of organic contaminants
Authors: Yuan Xiaojiao , Sun Mingxuan , Yao Yuan , Lin Xiaojing , Shi Jifeng
Published: January 2019

N/Ti3+-codoped triphasic TiO2/g-C3N4 heterojunctions were successfully prepared by a one-step in situ hydrothermal method, and they demonstrated considerably enhanced photocatalytic performance.
Synthesis, and spectroscopic, thermal and dielectric properties of phosphazene based ionic liquids: OFET application and tribological behavior
Authors: Akbaş Hüseyin , Karadağ Ahmet , Destegül Ali , Çakırlar Çiğdem , Yerli Yusuf , Tekin Kadir Cihan , Malayoğlu Uğur , Kılıç Zeynel
Published: January 2019

Mono(4-fluorobenzyl)cyclotriphosphazene derivatives with (dimethylamino)ethoxy (Pz1a–2a) and (dimethylamino)propoxy (Pz1b–2b) chains and their ionic liquids (PzIL1–PzIL4 and PzIL1a–PzIL4a) were synthesized.
What is the effect of Sn and Mo oxides on gold catalysts for selective oxidation of benzyl alcohol?
Authors: Xu Jing , Wang Yue , Cao Yunxiang , He Zhengke , Zhao Lianming , Etim Ubong Jerome , Bai Peng , Yan Zifeng , Wu Pingping
Published: January 2019

A series of SnOx and MoOx promoted gold nanoparticle catalysts were used for the aerobic oxidation of benzyl alcohol.
Towards homochiral supramolecular entities from achiral molecules by vortex mixing-accompanied self-assembly
Authors: Sang Yutao , Yang Dong , Duan Pengfei , Liu Minghua
Published: January 2019

By using a vortex mixing-accompanied self-assembly strategy, homochiral entities with controlled handedness were obtained from exclusively achiral molecules.
Surface phonons of lithium ion battery active materials
Authors: Benedek Peter , Yazdani Nuri , Chen Hungru , Wenzler Nils , Juranyi Fanni , Månsson Martin , Islam M. Saiful , Wood Vanessa C.
Published: January 2019

Surfaces of active materials are understood to play an important role in the performance and lifetime of lithium-ion batteries, but they remain poorly characterized and therefore cannot yet be systematically designed.
Organogels from trehalose difatty ester amphiphiles
Authors: Hibert G. , Fauquignon M. , Le Meins J.-F. , Pintori D. , Grau E. , Lecommandoux S. , Cramail H.
Published: January 2019

Saccharide diesters have been recently shown to be excellent gelators of vegetable oils.
Preparation of catalytic deep eutectic solvent-based silica microreactors using a non-aqueous sol–gel route
Authors: Batarseh Charlie , Levi-Zada Anat , Abu-Reziq Raed
Published: January 2019

We report the non-aqueous preparation of silica-based deep eutectic solvent microreactors. The palladium containing materials were applied in hydrogenation reactions.
Dendritic fibrous nano-particles (DFNPs): rising stars of mesoporous materials
Authors: Wang Yabin , Du Xin , Liu Zhong , Shi Shihui , Lv Haiming
Published: January 2019

This review article provides a comprehensive overview of the dendritic fibrous nano-particle (DFNP) family including its origin, synthesis methods, structural characteristics and models, promising applications, and so forth.
Enhancing photovoltaic performance by tuning the domain sizes of a small-molecule acceptor by side-chain-engineered polymer donors
Authors: Lin Yu-Che , Lu Yi-Ju , Tsao Cheng-Si , Saeki Akinori , Li Jia-Xing , Chen Chung-Hao , Wang Hao-Cheng , Chen Hsiu-Cheng , Meng Dong , Wu Kaung-Hsiung , Yang Yang , Wei Kung-Hwa
Published: January 2019

This paper reports side-chain-engineered polymer donors and a small-molecule acceptor that are capable of simultaneous charge and energy transfer as the active layer for organic photovoltaics.
Protective effects of resveratrol on biomarkers of oxidative stress, biochemical and histopathological changes induced by sub-chronic oral glyphosate-based herbicide in rats
Authors: Turkmen Ruhi , Birdane Yavuz Osman , Demirel Hasan Huseyin , Kabu Mustafa , Ince Sinan
Published: January 2019

The aim of this sub-chronic toxicity study is to determine the protective effects of Resveratrol (Res) on oxidative stress, biochemical and histopathological changes induced by glyphosate-based herbicide (GBH) in the blood, brain, heart, liver and renal tissues.
Strangers in strange lands: mitochondrial proteins found at extra-mitochondrial locations
Authors: Scanlon David P. , Salter Michael W.
Published: January 2019

The mitochondrial proteome is estimated to contain ∼1100 proteins, the vast majority of which are nuclear-encoded, with only 13 proteins encoded by the mitochondrial genome. The import of these nuclear-encoded proteins into mitochondria was widely believed to be unidirectional, but recent discoveries have revealed that many these ‘mitochondrial’ proteins are exported, and have extra-mitochondrial activities divergent from their mitochondrial function. Surprisingly, three of the exported proteins discovered thus far are mitochondrially encoded and have significantly different extra-mitochondrial roles than those performed within the mitochondrion. In this review, we will detail the wide variety of proteins once thought to only reside within mitochondria, but now known to ‘emigrate’ from mitochondria in order to attain ‘dual citizenship’, present both within mitochondria and elsewhere.
MOV10 sequesters the RNP of influenza A virus in the cytoplasm and is antagonized by viral NS1 protein
Authors: Li Jian , Hu Siqi , Xu Fengwen , Mei Shan , Liu Xiaoman , Yin Lijuan , Zhao Fei , Zhao Xiaoxiao , Sun Hong , Xiong Zichen , Zhang Di , Cen Shan , Wang Jianwei , Liang Chen , Guo Fei
Published: January 2019

MOV10 has emerged as an important host antiviral factor. MOV10 not only inhibits various viruses, including human immunodeficiency virus type 1, hepatitis C virus and vesicular stomatitis virus, but also restricts the activity of retroelements long interspersed nucleotide element-1, Alu, SVA and intracisternal A particles. Here, we report that MOV10 suppresses influenza A virus infection through interacting with viral nucleoprotein (NP), sequestering viral RNP in the cytoplasm and causing the degradation of viral vRNA. The antiviral activity of MOV10 depends on the integrity of P-bodies. We also found that the antiviral activity of MOV10 is partially countered by viral NS1 protein that interferes with the interaction of MOV10 with viral NP and causes MOV10 degradation through the lysosomal pathway. Moreover, NS1-defective influenza A virus is more susceptible to MOV10 restriction. Our data not only expand the antiviral spectrum of MOV10 but also reveal the NS1 protein as the first viral antagonist of MOV10.
Association of the gene polymorphisms of BMPR2, ACVRL1, SMAD9 and their interactions with the risk of essential hypertension in the Chinese Han population
Authors: Chen Yunpeng , Ye Chenxi , Chen Jingwen , Lin Dongming , Wang Hao , Wang Shen
Published: January 2019

Objective: Genetic factors are involved in the occurrence, development, and progression of essential hypertension (EH). To study the association between single nucleotide polymorphisms (SNPs) of the rs6435156 and rs1048829 loci of the bone morphogenetic protein receptor type 2 (BMPR2) gene, the rs121909287 and rs121909284 loci of the activin receptor-like kinase 1 (ACVRL1) gene, and the rs397514716 and rs121918359 loci of the mothers against decapentaplegic homolog 9 (SMAD9) gene with the risk of EH in the Chinese Han population. Materials and methods: A total of 460 EH patients and 460 healthy controls were recruited for the study. Genomic DNA of white blood cells was extracted, and the genotypes were analyzed by Sanger sequencing after polymerase chain reaction amplification. Multi-factor dimensionality reduction (MDR) was used to analyze the effect of gene–environment interactions on EH risk. Results: The risk of EH increased in the BMPR2 gene rs6435156 locus dominant model (adjusted odds ratio [OR] = 1.572, 95% confidence interval [CI]: 1.385–1.765, P<0.001) and recessive model (adjusted OR = 1.926, 95% CI: 1.693–2.067, P<0.001). The risk of EH increased in the rs1048829 recessive model (adjusted OR = 1.444, 95% CI: 1.142–1.696, P=0.003). The risk of EH increased in the recessive model of the ACVRL1 gene rs121909287 locus (adjusted OR = 1.403, 95% CI: 1.101–1.660, P=0.008). The risk of EH increased in the SMAD9 gene rs397514716 locus dominant model (adjusted OR = 1.370, 95% CI: 1.183–1.559, P<0.001) and recessive model (adjusted OR = 1.803, 95% CI: 1.470–1.983, P<0.001). The CG haplotype of the rs6435156 and rs1048829 loci of the BMPR2 gene, the CC haplotype of the ACVRL1 gene rs121909287 and rs121909284 loci, and the CC haplotype of the rs397514716 and rs121918359 loci of the SMAD9 gene were factors that protect against EH, whereas the TT haplotype of the rs6435156 and rs1048829 loci in the BMPR2 gene was a risk factor for EH. MDR analysis showed that the BMPR2 gene rs6435156 locus TT genotype carriers, the SMAD9 gene rs397514716 locus TT genotype carriers, and alcohol drinkers had the highest EH risk (OR = 4.523, 95% CI: 2.235–6.871, P<0.001). Conclusion: The SNPs of the rs6435156 and rs1048829 locus in the BMPR2 gene, the rs121909287 loci in the ACVRL1 gene, and the rs397514716 locus in the SMAD9 gene were associated with a risk of EH in Han Chinese.
Down-regulation of microRNA-34a-5p promotes trophoblast cell migration and invasion via targetting Smad4
Authors: Xue Fang , Yang Jing , Li Qirong , Zhou Haibin
Published: January 2019

Trophoblastic dysfunction, such as insufficient migration and invasion, is well-known to be correlated with preeclampsia (PE). Recently, microRNAs (miRNAs) have been implicated in diverse biological processes and human diseases, including PE. However, the expression and functions of miRNAs in the progression of PE, especially in the regulation of trophoblast cell migration and invasion remain largely unclear. Here, we compared the miRNAs expression profiles of PE patients with healthy controls using microarray assay and chose a significant increased miRNA-miR-34a-5p for further investigation. Overexpression of miR-34a-5p dramatically reduced migration and invasion in trophoblast HTR-8/SVneo cells, whereas enhanced by its inhibitor. Luciferase activity assay showed that miR-34a-5p directly target Smad family member 4 (Smad4), which is associated with cancer cell invasiveness and metastasis. We also found that Smad4 was down-regulated in PE patients, and an inverse relationship between Smad4 and miR-34a-5p expression levels was observed in placental tissues from PE patients. Further study showed that knockdown of Smad4 effectively attenuated the promoting effects of miR-34a-5p inhibition on the migration and invasion of HTR-8/SVneo cells. Taken together, these findings suggest that inhibition of miR-34a-5p improves invasion and migration of trophoblast cells by directly targetting Smad4, which indicated the potential of miR-34a-5p as a therapeutic target against PE.
Association of matrix Gla protein polymorphism and knee osteoarthritis in a chinese population
Authors: Hui Wenpeng , Cao Zhong , Wang Xiao , Zhu Junfeng
Published: January 2019

Several studies have explored the association between matrix Gla protein (MGP) gene polymorphism and knee osteoarthritis (OA) risk; however, they obtained conflicting findings. The present study aims to explore the association of MGP gene polymorphism and OA risk in a Chinese Han population. A total of 256 patients with radiographic knee OA and 327 control subjects were recruited in this case–control study. The genotypes of MGP gene rs1800802 polymorphism was determined by standard PCR and restriction fragment length polymorphism (PCR-RLFP). In this case–control study, we observed that MGP gene rs1800802 polymorphism increased the risk of knee OA. Subgroup analyses also found that rs1800802 polymorphism was related to the elevated risk for knee OA among the female, smoker, drinker, and body mass index (BMI) ≥25 kg/m2 groups. In conclusion, this study shows that MGP gene rs1800802 polymorphism is associated with increased risk for knee OA in Chinese Han population and the rs1800802 polymorphism may be a diagnostic marker of radiographic knee OA.
Sodium 4-phenylbutyrate treatment protects against renal injury in NZBWF1 mice
Authors: Bonnemaison Mathilde L. , Marks-Nelson Eileen S. , Boesen Erika I.
Published: January 2019

Systemic lupus erythematosus (SLE) is an autoimmune disease predominantly affecting women and often leading to lupus nephritis and kidney damage. Endoplasmic reticulum (ER) stress has been implicated in several forms of kidney disease, but whether ER stress contributes to renal injury in SLE is unknown. To investigate this, a small molecule chaperone, sodium 4-phenylbutyrate (4-PBA), was administered to the New Zealand Black x New Zealand White F1 hybrid (NZBWF1) mouse model of SLE. In a prevention study, treatment with 4-PBA from 20 weeks of age (prior to the development of renal injury) delayed the onset of albuminuria and significantly reduced additional indices of renal injury compared with vehicle-treated NZBWF1 mice at 36 weeks of age, including collagen deposition, tubular casts, renal cell apoptosis, and blood urea nitrogen (BUN) concentration. To test whether ER stress contributes to the progression of renal injury once albuminuria has developed, mice were monitored for the onset of albuminuria (3+ or ≥300 mg/dl by dipstick measurement of 24-h urine sample) and once established, were either killed (onset group), or underwent 4-PBA or vehicle treatment for 4 weeks. Treatment with 4-PBA blocked the worsening of glomerular injury, reduced the number of dilated or cast-filled tubules, and reduced the number of apoptotic cells compared with vehicle-treated mice. BUN and left ventricle to bodyweight ratio (LV:BW) were also reduced by 4-PBA treatment. Renal expression of the endogenous chaperones, protein disulphide isomerase (PDI), and 78 kDa glucose-regulated protein (GRP78, also known as binding Ig protein (BiP)), were increased in 4-PBA-treated mice. Together, these results suggest a therapeutic potential for agents like 4-PBA in combating renal injury in SLE.
Everyday Language Difficulties in Parkinson's Disease: Caregiver Description and Relationship With Cognition, Activities of Daily Living, and Motor Disability
Authors: Wolff Logan , Benge Jared
Published: January 2019

Purpose

Parkinson's disease (PD) impacts language in multiple ways, though important questions remain. The current article explores 2 main issues: what type of everyday language difficulties (ELDs) are noted by care partners and how do ELDs relate to cognition, daily activities, and motor disability in PD.

Method

Care partner reports of ELD were collected in 42 community-dwelling individuals with PD. Descriptive information of ELD was tallied, and the relationship of cognitive decline, activities of daily living (ADLs), and motor disability with ELD was evaluated.

Results

Forty-two percent of patients were described by care partners as having at least 1 consistent ELD, and the frequency of ELD increased in the presence of dementia, χ
2
(2) = 14.37,
p
= .0008. The most commonly described ELDs by caregivers were related to comprehension of instructions and deriving the point of conversations. ELD was correlated with worse cognition (
r
s
= −.524,
p
< .001), increased difficulty with daily activities (
r
s
= .634,
p
< .001), and increased motor dysfunction (
r
s
= .554,
p
< .001). Mild ADL decline (Functional Assessment Questionnaire score of 4); an area under the curve of .81 (
SE
= .07) was highly specific to the presence of ELD (95.4%).

Conclusions

Care partners note a variety of ELDs in patients with PD, most commonly comprehension difficulties. These difficulties increase with overall cognitive decline but are described in 30%–40% of those without significant cognitive deficits. ADL difficulties correlate with functional, motoric, and cognitive status, with even mild functional declines predictive of the presence of ELD. Implications for research and practice in this population are discussed.
Stellar ages, masses, and radii from asteroseismic modeling are robust to systematic errors in spectroscopy
Authors: Bellinger E. P. , Hekker S. , Angelou G. C. , Stokholm A. , Basu S.
Published: January 2019

Context. The search for twins of the Sun and Earth relies on accurate characterization of stellar and the exoplanetary parameters age, mass, and radius. In the modern era of asteroseismology, parameters of solar-like stars are derived by fitting theoretical models to observational data, which include measurements of their oscillation frequencies, metallicity [Fe/H], and effective temperature Teff. Furthermore, combining this information with transit data yields the corresponding parameters for their associated exoplanets.

Aims. While values of [Fe/H] and Teff are commonly stated to a precision of ∼0.1 dex and ∼100 K, the impact of systematic errors in their measurement has not been studied in practice within the context of the parameters derived from them. Here we seek to quantify this.

Methods. We used the Stellar Parameters in an Instant (SPI) pipeline to estimate the parameters of nearly 100 stars observed by Kepler and Gaia, many of which are confirmed planet hosts. We adjusted the reported spectroscopic measurements of these stars by introducing faux systematic errors and, separately, artificially increasing the reported uncertainties of the measurements, and quantified the differences in the resulting parameters.

Results. We find that a systematic error of 0.1 dex in [Fe/H] translates to differences of only 4%, 2%, and 1% on average in the resulting stellar ages, masses, and radii, which are well within their uncertainties (∼11%, 3.5%, 1.4%) as derived by SPI. We also find that increasing the uncertainty of [Fe/H] measurements by 0.1 dex increases the uncertainties of the ages, masses, and radii by only 0.01 Gyr, 0.02 M⊙, and 0.01 R⊙, which are again well below their reported uncertainties (∼0.5 Gyr, 0.04 M⊙, 0.02 R⊙). The results for Teff at 100 K are similar.

Conclusions. Stellar parameters from SPI are unchanged within uncertainties by errors of up to 0.14 dex or 175 K. They are even more robust to errors in Teff than the seismic scaling relations. Consequently, the parameters for their exoplanets are also robust.
Existence of positive solution for a planar Schrödinger-Poisson system with exponential growth
Authors: Alves Claudianor O. , Figueiredo Giovany M.
Published: January 2019

In this paper, we prove the existence of a positive solution with minimal energy for a planar Schrödinger-Poisson system, where the nonlinearity is a continuous function with exponential critical growth. We find this solution using a minimization technique on the Nehari manifold.
Suppression of secondary emission of electrons from end plate in expander of open trap
Authors: Skovorodin D. I.
Published: January 2019

The influence of secondary emission from the end plate in the expander divertor on the energy confinement in linear plasma devices was considered. A numerical model was developed to calculate a distribution of the electric potential along a magnetic field line in the expander divertor. The model assumes weak collisions and the absence of cross-field losses of both ions and electrons. The potential profiles in the case of both no and strong secondary emission are presented. It was shown that expansion of the magnetic field in the divertor can effectively suppress the influence of cold electrons on energy confinement even if the secondary emission coefficient is more than unity. The dependence of energy lost per one ion leaving the mirror on the secondary emission coefficient was studied. The influence of partial energy recuperation by cold electrons on the total energy balance was discussed. It has been shown that the energy loss per one ion is not sensitive to the recirculation of cold electrons if the secondary emission coefficient is not too large.
Size-dependent proton localization in hydrated uracil clusters: A joint experimental and theoretical study
Authors: Braud Isabelle , Zamith Sébastien , Cuny Jérôme , Zheng Linjie , L’Hermite Jean-Marc
Published: January 2019

A collision-induced dissociation study of hydrated protonated uracil (H2O)n=1-15UH+ clusters is reported. The mass-selected clusters collide with water molecules and rare gases at a controlled center of mass collision energy. From these measurements, absolute fragmentation cross sections and branching ratios are extracted as a function of the uracil hydration. For small clusters, up to n = 4, we observe that only neutral water molecules are evaporated upon collisions, whereas, for larger clusters, neutral uracil is also evaporated: this transition in the nature of the evaporation products is interpreted considering the lowest-energy isomers of each species that are obtained from a combination of density-functional based tight-binding and MP2 calculations. The simulations show that in (H2O)1-4UH+ the proton is located on the uracil molecule or on a water molecule strongly bound to uracil whereas, in larger clusters, the proton is bound to water molecules far from uracil. This correlation between the structure of the low-energy isomers and the experimental fragmentation channel suggests that dissociation may occur in a very short time after collisions so that energy has not enough time to be redistributed among all degrees of freedom and the ground-state geometry of the parent cluster partly determines the nature of the favored fragmentation channels. Of course, thermal dissociations originating from long lived, thus thermalized, collision complexes cannot be ruled out but they are not expected to play the major role since the experimental results can be satisfactorily accounted for by assuming that the fragmentation processes are mainly impulsive.
Configuration interaction singles with spin-orbit coupling: Constructing spin-adiabatic states and their analytical nuclear gradients
Authors: Bellonzi Nicole , Medders Gregory R. , Epifanovsky Evgeny , Subotnik Joseph E.
Published: January 2019

For future use in modeling photoexcited dynamics and intersystem crossing, we calculate spin-adiabatic states and their analytical nuclear gradients within configuration interaction singles theory. These energies and forces should be immediately useful for surface hopping dynamics, which are natural within an adiabatic framework. The resulting code has been implemented within the Q-Chem software and preliminary results suggest that the additional cost of including spin-orbit coupling within the singles-singles block is not large.
On the local aspects of distributional chaos
Authors: Pawlak Ryszard J. , Loranty Anna
Published: January 2019

In this paper, the notion of a distributionally chaotic point (connected with focusing of an uncountable distributionally scrambled set and its envelope around this point) is introduced. The theorems dealing with the existence of such points for selfmaps of the closed unit interval and the possibilities of approximation of nonautonomous discrete dynamical systems by systems with i-stable and p-DC1 points are proved.
Increased energy efficiency spin-torque switching of magnetic tunnel junction devices with a higher order perpendicular magnetic anisotropy
Authors: Lavanant Marion , Petit-Watelot Sebastien , Kent Andrew D. , Mangin Stephane
Published: January 2019

We study the influence of a second order magnetic anisotropy on magnetization reversal by spin transfer torque in perpendicularly magnetized magnetic tunnel junctions (pMTJs). Using a macrospin model to describe the dynamics of the free layer, analytical solutions for the switching voltage and the voltage threshold for precession are determined as a function of the first and second order magnetic anisotropies. To compare the spin-transfer-torque energy efficiency to that of a classical pMTJ, a junction without the second order anisotropy term, we compare these cases at a fixed energy barrier to thermally activated reversal. We show that the critical voltage for switching can be reduced by a factor 0.7 when the ratio of the second to the first order magnetic anisotropy is 1/3. Importantly, the switching time can be reduced by nearly a factor of two for this magnetic anisotropy ratio. These results highlight an important and practical method to increase the spin-torque efficiency, while reducing the energy dissipation and switching time in magnetic random access memory devices.
A washer gun plasma system for microwave—plasma interaction experiments
Authors: V. P. Anitha , Rathod Priyavandana J. , Raval Jayesh , Bahl Renu , Saxena Y. C.
Published: January 2019

A washer-gun based plasma system has been developed to enable high power microwave (HPM)—plasma interaction in a system for microwave plasma experiments. The critical pre-requisites of the plasma are density, ne ∼ (1–10) × 1017 m−3, uniformity over a radial extent ≈10 cm and axial extent ≈20–30 cm, an axial density gradient of scale-length Ln ≈ wavelength of HPM, and ambient pressure low enough to maintain electron-neutral collision frequency much less than plasma frequency. The system developed deploys a ten stage pulse forming network, discharged to the washer-gun to produce pulsed (τpulse ∼ 100 μs) discharges that get ejected into an experimental chamber. The system is capable of generating ne ∼ 1018 m−3 and Te ∼ 10 eV. Temporal and spatial regimes are identified to obtain the required extents of radial and axial ne uniformity of 10 cm and 20 cm, respectively, and a steep axial gradient Ln ≈ 10 cm. Based on the desired frequency of the interacting HPM (in the range 3-5 GHz) planned for a particular experimental campaign, the density and spatial density profiles of the plasma can be tailored. The present paper presents an account of the plasma source and characterization of the plasma.
Heterogeneity in relaxation rate improves the synchronization of oscillatory neurons in a model of the SCN
Authors: Gu Changgui , Yang Huijie , Wang Man , Rohling Jos H. T.
Published: January 2019

The circadian rhythms in mammals, that are regulated by the suprachiasmatic nucleus (SCN) of the brain, have been observed even in the absence of a light-dark cycle. The SCN is composed of about 10 000 autonomous neuronal oscillators, which are heterogenous in many oscillatory properties, including the heterogeneity in relaxation rates. Although the relaxation rate affects the entrainability of the SCN as a whole, not much is known about the reasons why the heterogeneity in relaxation rate exists. In the present study, based on a Poincaré model, we examine whether the heterogeneity in the relaxation rate affects the synchronization of the SCN neuronal oscillators under constant darkness. Both our simulations and theoretical results show that the heterogeneity improves the synchronization. Our findings provide an alternative explanation for the existence of the heterogeneity in the SCN neurons and shed light on the effect of neuronal heterogeneity on the collective behavior of the SCN neurons.
Exploring a new ammeter traceability route for ionisation chamber measurements
Authors: Giblin S. P. , Lorusso G.
Published: January 2019

We compared the performance of a commercial ammeter and a home-made integrating electrometer in reading ionisation chamber currents less than 100 pA. The integrating electrometer charges a capacitor with the unknown current and measures the resulting rate of change of voltage, whereas the ammeter uses a high-value resistor as the feedback element to an amplifier which converts current to voltage. The noise performance of both systems was very similar for averaging times less than 1000 s. Both systems were calibrated using a reference current source with 1 part per million (ppm) accuracy, revealing an error of 460 ppm in the electrometer indicated current, of unknown origin. This error is well within the uncertainty budget for radionuclide calibrations but much larger than the individual uncertainties in the traceable calibrations of capacitance, voltage, and time. The noise in the ionisation chamber current was much larger than the noise floor of both instruments, with tests providing strong indication that the excess noise originated in the high voltage source used for energising the chamber.
Imaging of material defects with a radio-frequency atomic magnetometer
Authors: Bevington P. , Gartman R. , Chalupczak W.
Published: January 2019

Non-destructive inductive testing of defects in metal plates using the magnetic resonance signal of a radio-frequency atomic magnetometer is demonstrated. The shape and amplitude of the spatial profile of the signal features, which represent structural defects, are explored. By comparing numerical and experimental results on a series of benchmark aluminium plates, we show correspondence between the properties of the secondary field and those of the magnetometer signal. In particular, we show that two components of the secondary field are mapped onto the amplitude and phase of the atomic magnetometer signal. Hence, a magnetic field measurement with the atomic magnetometer, although scalar in its nature, provides semi-vectorial information on the secondary field. Moreover, we demonstrate a robust process for determining defect dimensions, which is not limited by the size of the sensor. We prove that the amplitude and phase contrast of the observed profiles enables us to reliably measure defect depth.
Properties of high-energy electron beams trap with a magnetic mirror field
Authors: Zhang Heng , Wang Fang-Ping , Lin Mai-Mai , Zhao Xiao-Yin , Duan Wen-Shan , Yang Lei
Published: January 2019

The properties of a high energy short pulse electron beam in a magnetic mirror field are studied numerically by the Particle-in-Cell method. The complex nature of processes studied, and also the need for the calculation of the positions, velocities, and trajectories of billions of particles, required the use of a scalable parallel algorithm. The use of modern supercomputers has allowed us to calculate the plasma dynamics, to determine the electron beam in the magnetic mirror field. Mathematical modeling of non-neutral plasma dynamics at the trap is carried out. The axially integrated radial density profiles, electric field distribution, and phase space distribution of velocity are measured. The axial and radial oscillations of a confined non-neutral plasma are also observed.
Structural and chemical homogeneity of chalcogenide glass prepared by melt-rocking
Authors: Lucas Pierre , Coleman Garrett J. , Sen Sabyasachi , Cui Shuo , Guimond Yann , Calvez Laurent , Boussard-Pledel Catherine , Bureau Bruno , Troles Johann
Published: January 2019

The chemical and structural homogeneity of selenide glasses produced by mechanical homogenization of the melt in a rocking furnace is investigated by Raman and Energy Dispersive Spectroscopy (EDS). Both techniques demonstrate that the glass is macroscopically homogeneous along the entire length of a 6 cm rod. EDS imaging performed over four orders of magnitude in scale further confirms that the glass is homogeneous down to the sub-micron scale. An estimate of the diffusion coefficient from experimental viscosity data shows that the diffusion length is far larger than the resolution of EDS and therefore confirms that the glass is homogeneous at any length scale. In order to investigate a systematic mismatch in physical properties reported in the literature for glasses produced by extended static homogenization, two germanium selenide samples are produced under the same conditions except for the homogenization step: one in a rocking furnace for 10 h and the other in a static furnace for 192 h. No difference in physical properties is found between the two glasses. The properties of an ultra-high purity glass are also found to be identical. The origin of the systematic deviation reported in the literature for germanium selenide glasses is therefore still unknown, but the present results demonstrate that homogeneity or dryness does not have a significant contribution in contrast to previous suggestions. The implications of glass homogeneity for technological applications and industrial production are discussed.
A variable stiffness strategy for improving comprehensive performances of micromachined electrostatic switches
Authors: Xiang Xiaojian , Dai Xuhan , Cheng Ping , Wang Kai , Sun Shi , Ding Guifu
Published: January 2019

Contact bounce, high driving voltage, and poor robustness to process deviations are the main bottlenecks that limit the reliability of MEMS electrostatic switches. In this study, a variable stiffness strategy offers an optimized path to reach the closure position for the movable electrode. In the proposed method, the switching system's stiffness is low enough to reduce the driving voltage at the initial stage but increases rapidly as the movable electrode approaches the closure position for braking. Our experimental results prove that this strategy can suppress contact bounce, reduce pull-in voltage without compromising pull-in time, and also enhance robustness to process deviations, improving the overall reliability of the MEMS switches.
Computational analysis of self-similar capillary-driven thinning and pinch-off dynamics during dripping using the volume-of-fluid method
Authors: Dinic Jelena , Sharma Vivek
Published: January 2019

Drop formation and detachment involve large topological changes, including the formation of a fluid neck that thins down due to surface tension-driven flows, and at the neck pinch-off, properties like Laplace pressure display a finite time singularity. Accurately simulating large topological deformations and nonlinearities encountered during drop formation typically makes numerical simulations computationally demanding as resolving small features close to the pinch-off instant requires high resolution and accuracy. In spite of the inherent advantages in tracking interfaces, preserving mass and computational time needed, very few studies utilize the volume-of-fluid (VOF) method for drop formation studies as early practitioners reported convergence problems for fluids with viscosity greater than ten times water viscosity. In this contribution, we utilize the VOF method as implemented in FLOW-3D to simulate the prototypical free surface flow of dripping for Newtonian fluids, including viscosity values four orders of magnitude higher than water viscosity. We benchmark the simulated neck shape, neck evolution rate, and break-up length against experiments carried out as a part of this study. The pinch-off dynamics are determined by a complex interplay of inertial, viscous, and capillary stresses, and self-similar scaling laws that are contrasted here against both experiments and simulations often describe the dynamics. We show that the simulated radius evolution profiles match the pinch-off dynamics that are experimentally observed and theoretically predicted for Newtonian fluids for axisymmetric flows. Furthermore, we determine pre-factors for scaling laws, velocity, and deformation fields within thinning necks, and we show that pre-factors, as well as break-up time and length comparable to experiments can be simulated using the VOF method.
Long-time asymptotics for the Sasa–Satsuma equation via nonlinear steepest descent method
Authors: Liu Nan , Guo Boling
Published: January 2019

We formulate a 3 × 3 Riemann–Hilbert problem to solve the Cauchy problem for the Sasa–Satsuma equation on the line, which allows us to give a representation for the solution of the Sasa–Satsuma equation. We then apply the method of nonlinear steepest descent to compute the long-time asymptotics of the Sasa–Satsuma equation.
Binding preference of nitroimidazolic radiosensitizers to nucleobases and nucleosides probed by electrospray ionization mass spectrometry and density functional theory
Authors: Pandeti S. , Feketeová L. , Reddy T. J. , Abdoul-Carime H. , Farizon B. , Farizon M. , Märk T. D.
Published: January 2019

Nitroimidazolic radiosensitizers are used in radiation therapy to selectively sensitize cancer cells deprived of oxygen, and the actual mechanism of radiosensitization is still not understood. Selecting five radiosensitizers (1-methyl-5-nitroimidazole, ronidazole, ornidazole, metronidazole, and nimorazole) with a common 5-nitroimidazolic ring with different substitutions at N1 and C2 positions of the imidazole moiety, we investigate here their binding to nucleobases (A, T, G, and C) and nucleosides (As, Td, Gs, and Cd) via the positive electrospray ionization mass spectrometry experiments. In addition, quantum chemical calculations at the M062x/6-311+G(d,p) level of theory and basis set were used to determine binding energies of the proton bound dimers of a radiosensitizer and a nucleobase. The positive electrospray ionization leads to the formation of proton bound dimers of all radiosensitizers except 1-methyl-5-nitroimidazole in high abundance with C and smaller abundance with G. Ronidazole and metronidazole formed less abundant dimers also with A, while no dimers were observed to be formed at all with T. In contrast to the case of the nucleoside Td, the dimer intensity is as high as that with Cd, while the abundance of the dimer with Gs is smaller than that of the former. The experimental results are consistent with the calculations of binding energies suggesting proton bound dimers with C and G to be the strongest bound ones. Finally, a barrier-free proton transfer is observed when protonated G or C approaches the nitroimidazole ring.
Ultrafast field-free magnetization switching using bi-directional spin Hall current and antiferromagnetic interlayer exchange
Authors: Li Xiaoguang , Kang Aiguo , Liu Zhejie , Zhou Yan
Published: January 2019

We present an approach to realize ultrafast field-free spin-orbit torque (SOT) switching of a ferromagnetic layer with perpendicular magnetic anisotropy. In this scheme, the heavy metal layer serves as both the spin Hall channel and the interlayer exchange spacer. The magnetization switching of the adjacent ferromagnetic layer is driven by magnetic inertia, exhibiting intriguing and rich switching behavior under current pulses of different amplitudes and durations. Based on the macrospin simulation, we investigated the switching behavior of the composite-free layer, i.e., two antiferromagnetically coupled ferromagnetic layers, and demonstrated the possibility of field-free switching within tens of picoseconds. Our results show that the positive sign product of field-like SOT and damping-like SOT and the strong antiferromagnetic exchange between the two coupled ferromagnetic layers are critical to realize the deterministic switching. This work is expected to stimulate further experimental efforts for designing high performance magnetic random-access memory application.