bluuebunny/crossref_metadata_2025 huggingface dataset:
A Novel Modeling in Mathematical Biology for Classification of Signal Peptides
Authors: Ehsan Asma , Mahmood Khalid , Khan Yaser Daanial , Khan Sher Afzal , Chou Kuo-Chen
Published: January 2018

The molecular structure of macromolecules in living cells is ambiguous unless we classify them in a scientific manner. Signal peptides are of vital importance in determining the behavior of newly formed proteins towards their destined path in cellular and extracellular location in both eukaryotes and prokaryotes. In the present research work, a novel method is offered to foreknow the behavior of signal peptides and determine their cleavage site. The proposed model employs neural networks using isolated sets of prokaryote and eukaryote primary sequences. Protein sequences are classified as secretory or non-secretory in order to investigate secretory proteins and their signal peptides. In comparison with the previous prediction tools, the proposed algorithm is more rigorous, well-organized, significantly appropriate and highly accurate for the examination of signal peptides even in extensive collection of protein sequences.
An ethylene response factor (MxERF4) functions as a repressor of Fe acquisition in Malus xiaojinensis
Authors: Liu Wei , Wu Ting , Li Qiwei , Zhang Xinzhong , Xu Xuefeng , Li Tianhong , Han Zhenhai , Wang Yi
Published: January 2018

Iron (Fe) is an essential element for plants; however, its availability is limited as it forms insoluble complexes in the soil. Consequently, plants have developed mechanisms to adapt to low Fe conditions. We demonstrate that ethylene is involved in Fe deficiency-induced physiological responses in Malus xiaojinensis, and describe the identification of MxERF4 as a protein-protein interaction partner with the MxFIT transcription factor, which is involved in the iron deficiency response. Furthermore, we demonstrate that MxERF4 acts as an MxFIT interaction partner to suppresses the expression of the Fe transporter MxIRT1, by binding directly to its promoter, requiring the EAR motif of the MxERF4 protein. Suppression of MxERF4 expression in M. xiaojinensis, using virus induced gene silencing resulted in an increase in MxIRT1 expression. Taken together, the results suggest a repression mechanism, where ethylene initiates the Fe deficiency response, and the response is then dampened, which may require a transient inhibition of Fe acquisition via the action of MxERF4.
Macrophage sensing of single-walled carbon nanotubes via Toll-like receptors
Authors: Mukherjee Sourav P. , Bondarenko Olesja , Kohonen Pekka , Andón Fernando T. , Brzicová Táňa , Gessner Isabel , Mathur Sanjay , Bottini Massimo , Calligari Paolo , Stella Lorenzo , Kisin Elena , Shvedova Anna , Autio Reija , Salminen-Mankonen Heli , Lahesmaa Riitta , Fadeel Bengt
Published: January 2018

Carbon-based nanomaterials including carbon nanotubes (CNTs) have been shown to trigger inflammation. However, how these materials are ‘sensed’ by immune cells is not known. Here we compared the effects of two carbon-based nanomaterials, single-walled CNTs (SWCNTs) and graphene oxide (GO), on primary human monocyte-derived macrophages. Genome-wide transcriptomics assessment was performed at sub-cytotoxic doses. Pathway analysis of the microarray data revealed pronounced effects on chemokine-encoding genes in macrophages exposed to SWCNTs, but not in response to GO, and these results were validated by multiplex array-based cytokine and chemokine profiling. Conditioned medium from SWCNT-exposed cells acted as a chemoattractant for dendritic cells. Chemokine secretion was reduced upon inhibition of NF-κB, as predicted by upstream regulator analysis of the transcriptomics data, and Toll-like receptors (TLRs) and their adaptor molecule, MyD88 were shown to be important for CCL5 secretion. Moreover, a specific role for TLR2/4 was confirmed by using reporter cell lines. Computational studies to elucidate how SWCNTs may interact with TLR4 in the absence of a protein corona suggested that binding is guided mainly by hydrophobic interactions. Taken together, these results imply that CNTs may be ‘sensed’ as pathogens by immune cells.
Changes in cytokine responses to TB antigens ESAT-6, CFP-10 and TB 7.7 and inflammatory markers in peripheral blood during therapy
Authors: Leem Ah Young , Song Joo Han , Lee Eun Hye , Lee Hyejon , Sim Bora , Kim Song Yee , Chung Kyung Soo , Kim Eun Young , Jung Ji Ye , Park Moo Suk , Kim Young Sam , Chang Joon , Kang Young Ae
Published: January 2018

Multiple cytokines and inflammatory markers control TB infection. We aimed to investigate the changes in multiple cytokines and inflammatory markers in active TB patients following anti-TB drug therapy. Twenty-nine patients with active TB were recruited prospectively between December 2010 and July 2017. Blood samples were collected before (T0), after 2 months (T2), and at the end of anti-TB treatment (Tend). We measured the levels of Interferon (IFN)-γ, interleukin (IL)-2, IL-12, IL-10, IL-13 and tumor necrosis factor (TNF)-α in supernatants collected from the QuantiFERON-TB Gold In-Tube assay (QFT-GIT), as well as the WBC, neutrophil, platelet count and neutrophil to lymphocyte ratio (NLR) in whole blood. Compared with baseline levels, WBC, neutrophil, and platelet counts were significantly lower following treatment. In addition, the NLR after treatment significantly decreased compared with baseline, whereas the IL-2/IFN-γ ratio increased after treatment. In conclusion, the levels of IL-2/IFN-γ ratios in the supernatant and the NLR might be useful biomarkers to evaluate the effectiveness of drug therapy in active TB patients.
The gamma gap predicts 4-year all-cause mortality among nonagenarians and centenarians
Authors: Yang Ming , Xie Linlin , Liu Xiu , Hao Qiukui , Jiang Jiaojiao , Dong Birong
Published: January 2018

Recent studies have revealed the prognostic role of the gamma gap, the total serum proteins concentration minus the albumin concentration, for predicting all-cause mortality among adults. This study aims to investigate the relationship between the gamma gap and all-cause mortality among nonagenarians and centenarians via a secondary data analysis of a prospective observational study. The analysis included 801 participants (260 men and 541 women, mean age: 93.7 ± 3.5 years), 46 of which were lost at the 4-year follow-up. The mean gamma gap was 2.7 ± 0.5 g/dl. After adjusting for relevant confounders, the gamma gap was significantly associated with 4-year all-cause mortality (hazard ratio [HR] per 1-SD = 1.22, 95% confidential interval [CI]: 1.12–1.78). Using different cut-off points, the elevated gamma gap could be defined as ≥2.9, 3.0, 3.1, or 3.2 g/dl. The relevant HRs and 95% CIs of the elevated gamma gap for predicting mortality were 1.27 (1.12–1.90), 1.29 (1.03–1.78), 1.21 (1.23–1.66), and 1.26 (1.09–1.69), respectively. In conclusion, the gamma gap is an independent prognostic factor for long-term mortality in nonagenarians and centenarians. A value greater than or equal to 3.1 g/dl may define an elevated gamma gap, but further studies are required.
Two-color second-order sideband generation in an optomechanical system with a two-level system
Authors: Kong Cui , Li Sha , You Cai , Xiong Hao , Wu Ying
Published: January 2018

Second-order sideband generation in an optomechanical system with the coupling between a mechanical resonator and a two-level system is discussed beyond the conventional linearized description of optomechanical interactions. The features of two-color second-order sideband generation are demonstrated in this hybrid system. We discovery that the switch between one- and two-color second-order sideband generation is easily realized by shifting the detuning between the control field and the cavity field or the transition frequency of the two-level system. The efficiency of two-color second-order sideband generation increases monotonously with the control field strength. The coupling strength between the mechanical resonator and the two-level system plays a decisive role in the appearance of the two-color second-order sidebands. The two-color second-order sideband generation may provide measurement with higher precision in new degrees of freedom.
Triggering molecular assembly at the mesoscale for advanced Raman detection of proteins in liquid
Authors: Banchelli Martina , de Angelis Marella , D’Andrea Cristiano , Pini Roberto , Matteini Paolo
Published: January 2018

An advanced optofluidic system for protein detection based on Raman signal amplification via dewetting and molecular gathering within temporary mesoscale assemblies is presented. The evaporation of a microliter volume of protein solution deposited in a circular microwell precisely follows an outward-receding geometry. Herein the combination of liquid withdrawal with intermolecular interactions induces the formation of self-assembled molecular domains at the solid-liquid interface. Through proper control of the evaporation rate, amplitude of the assemblies and time for spectral collection at the liquid edge are extensively raised, resulting in a local enhancement and refinement of the Raman response, respectively. Further signal amplification is obtained by taking advantage of the intense local electromagnetic fields generated upon adding a plasmonic coating to the microwell. Major advantages of this optofluidic method lie in the obtainment of high-quality, high-sensitivity Raman spectra with detection limit down to sub-micromolar values. Peculiarly, the assembled proteins in the liquid edge region maintain their native-like state without displaying spectral changes usually occurring when dried drop deposits are considered.
Individuals with depressive tendencies experience difficulty in forgetting negative material: two mechanisms revealed by ERP data in the directed forgetting paradigm
Authors: Xie Hui , Jiang Donghong , Zhang Dandan
Published: January 2018

Although previous studies have shown that individuals with depressive tendencies have deficits in forgetting negative material, the detailed underlying neural mechanisms have not been elucidated. This study examined the intentional forgetting of negative and neutral material in individuals with depressive tendencies in two phases. In the study phase, the participants performed a directed forgetting task, where a total of 320 words were presented to them, each followed by an instructive cue to forget or remember the previously presented word. Subsequently, in the memory recognition test phase, the participants completed the “old or new discrimination task”. The results indicated that individuals with depressive tendencies had difficulties suppressing the memory encoding of negative words, while the suppression of memory encoding of neutral words was relatively intact. Moreover, individuals with depressive tendencies displayed enhanced word-evoked P2 and late positive potential for negative items, as well as enhanced cue-evoked P1 and N2 for the negative items that were required to be forgotten, as compared to individuals without depressive tendencies. Based on these results, we propose two mechanisms that may contribute to the failure of forgetting negative material in mild depression: (1) inefficient memory suppression and early selective attention, and (2) excessive preliminary processing.
PLK1 protects against sepsis-induced intestinal barrier dysfunction
Authors: Cao Yingya , Chen Qun , Wang Zhen , Yu Tao , Wu Jingyi , Jiang Xiaogan , Jin Xiaoju , Lu Weihua
Published: January 2018

Sepsis and sepsis-associated intestinal barrier dysfunction are common in intensive care units, with high mortality. The aim of this study is to investigate whether Polo-like kinase 1 (PLK1) ameliorates sepsis-induced intestinal barrier dysfunction in the intestinal epithelium. The mouse intestinal barrier was disrupted after Lipopolysaccharide (LPS) injection due to intestinal epithelial cell apoptosis and proliferation inhibition, accompanied by decreased PLK1. In HT-29 intestinal epithelial cells, LPS stimulation induced cell apoptosis and inhibited cell proliferation. Overexpression of PLK1 partly rescued the apoptosis and proliferation inhibition in HT29 cells caused by LPS. Finally, LPS stimulation promoted the reduction of PLK1, resulting in apoptosis and proliferation inhibition in intestinal epithelial cells, disrupting the intestinal epithelial barrier. These findings indicate that PLK1 might be a potential therapeutic target for the treatment of sepsis-induced intestinal barrier dysfunction.
Defects in the mitochondrial-tRNA modification enzymes MTO1 and GTPBP3 promote different metabolic reprogramming through a HIF-PPARγ-UCP2-AMPK axis
Authors: Boutoual Rachid , Meseguer Salvador , Villarroya Magda , Martín-Hernández Elena , Errami Mohammed , Martín Miguel A. , Casado Marta , Armengod M.-Eugenia
Published: January 2018

Human proteins MTO1 and GTPBP3 are thought to jointly catalyze the modification of the wobble uridine in mitochondrial tRNAs. Defects in each protein cause infantile hypertrophic cardiomyopathy with lactic acidosis. However, the underlying mechanisms are mostly unknown. Using fibroblasts from an MTO1 patient and MTO1 silenced cells, we found that the MTO1 deficiency is associated with a metabolic reprogramming mediated by inactivation of AMPK, down regulation of the uncoupling protein 2 (UCP2) and transcription factor PPARγ, and activation of the hypoxia inducible factor 1 (HIF-1). As a result, glycolysis and oxidative phosphorylation are uncoupled, while fatty acid metabolism is altered, leading to accumulation of lipid droplets in MTO1 fibroblasts. Unexpectedly, this response is different from that triggered by the GTPBP3 defect, as GTPBP3-depleted cells exhibit AMPK activation, increased levels of UCP2 and PPARγ, and inactivation of HIF-1. In addition, fatty acid oxidation and respiration are stimulated in these cells. Therefore, the HIF-PPARγ-UCP2-AMPK axis is operating differently in MTO1- and GTPBP3-defective cells, which strongly suggests that one of these proteins has an additional role, besides mitochondrial-tRNA modification. This work provides new and useful information on the molecular basis of the MTO1 and GTPBP3 defects and on putative targets for therapeutic intervention.
150,000-year palaeoclimate record from northern Ethiopia supports early, multiple dispersals of modern humans from Africa
Authors: Lamb Henry F. , Bates C. Richard , Bryant Charlotte L. , Davies Sarah J. , Huws Dei G. , Marshall Michael H. , Roberts Helen M. , Toland Harry
Published: January 2018

Climatic change is widely acknowledged to have played a role in the dispersal of modern humans out of Africa, but the timing is contentious. Genetic evidence links dispersal to climatic change ~60,000 years ago, despite increasing evidence for earlier modern human presence in Asia. We report a deep seismic and near-continuous core record of the last 150,000 years from Lake Tana, Ethiopia, close to early modern human fossil sites and to postulated dispersal routes. The record shows varied climate towards the end of the penultimate glacial, followed by an abrupt change to relatively stable moist climate during the last interglacial. These conditions could have favoured selection for behavioural versatility, population growth and range expansion, supporting models of early, multiple dispersals of modern humans from Africa.
Dynamic cellular maps of molecular species: Application to drug-target interactions
Authors: García Carolina , Losada Alejandro , Sacristán Miguel A. , Martínez-Leal Juan Fernando , Galmarini Carlos M. , Lillo M. Pilar
Published: January 2018

The design of living cell studies aimed at deciphering the mechanism of action of drugs targeting proteins with multiple functions, expressed in a wide range of concentrations and cellular locations, is a real challenge. We recently showed that the antitumor drug plitidepsin (APL) localizes sufficiently close to the elongation factor eEF1A2 so as to suggest the formation of drug-protein complexes in living cells. Here we present an extension of our previous micro-spectroscopy study, that combines Generalized Polarization (GP) images, with the phasor approach and fluorescence lifetime imaging microscopy (FLIM), using a 7-aminocoumarin drug analog (APL*) as fluorescence tracer. Using the proposed methodology, we were able to follow in real time the formation and relative distribution of two sets of APL-target complexes in live cells, revealing two distinct patterns of behavior for HeLa-wt and APL resistant HeLa-APL-R cells. The information obtained may complement and facilitate the design of new experiments and the global interpretation of the results obtained with other biochemical and cell biology methods, as well as possibly opening new avenues of study to decipher the mechanism of action of new drugs.
Effects of vitamin D supplementation on inflammatory markers in heart failure: a systematic review and meta-analysis of randomized controlled trials
Authors: Rodriguez Alexander J. , Mousa Aya , Ebeling Peter R. , Scott David , de Courten Barbora
Published: January 2018

Vitamin D is reported to have anti-inflammatory properties; however the effects of vitamin D supplementation on inflammation in patients with heart failure (HF) have not been established. We performed a systematic review and meta-analysis examining effects of vitamin D supplementation on inflammatory markers in patients with HF. MEDLINE, CINAHL, EMBASE, All EBM, and Clinical Trials registries were systematically searched for RCTs from inception to 25 January 2017. Two independent reviewers screened all full text articles (no date or language limits) for RCTs reporting effects of vitamin D supplementation (any form, route, duration, and co-supplementation) compared with placebo or usual care on inflammatory markers in patients with heart failure. Two reviewers assessed risk of bias and quality using the grading of recommendations, assessment, development, and evaluation approach. Seven studies met inclusion criteria and six had data available for pooling (n = 1012). In meta-analyses, vitamin D-supplemented groups had lower concentrations of tumor necrosis factor-alpha (TNF-α) at follow-up compared with controls (n = 380; p = 0.04). There were no differences in C-reactive protein (n = 231), interleukin (IL)-10 (n = 247) or IL-6 (n = 154) between vitamin D and control groups (all p > 0.05). Our findings suggest that vitamin D supplementation may have specific, but modest effects on inflammatory markers in HF.
An [Mn2(bpmp)]3+ complex as an artificial peroxidase and its applications in colorimetric pyrophosphate sensing and cascade-type pyrophosphatase assay
Authors: Lee Youngkeun , Yoo Soyeon , Kang Seungyoon , Hong Sukwon , Han Min Su
Published: January 2018

An [Mn2(bpmp)]3+ complex was developed as an artificial peroxidase and applied to colorimetric PPi detection and cascade-type PPase assay.
Mussel-inspired graphene oxide nanosheet-enwrapped Ti scaffolds with drug-encapsulated gelatin microspheres for bone regeneration
Authors: Han Lu , Sun Honglong , Tang Pengfei , Li Pengfei , Xie Chaoming , Wang Menghao , Wang Kefeng , Weng Jie , Tan Hui , Ren Fuzeng , Lu Xiong
Published: January 2018

A mussel-inspired modification method was employed for depositing GO on inert Ti scaffolds to obtain GO/Ti hybrid scaffolds.
Toward a rational photocatalyst design: a new formation strategy of co-catalyst/semiconductor heterostructures via in situ exsolution
Authors: Sun Yi-Fei , Yang Yan-Ling , Chen Jian , Li Meng , Zhang Ya-Qian , Li Jian-Hui , Hua Bin , Luo Jing-Li
Published: January 2018

A new “post-growth” approach to implant metal sulfide nanodots (<5 nm) with high population and uniform dispersion into a semiconductor parent matrix was reported.
A significant role of non-thermal equilibrated electrons in the formation of deleterious complex DNA damage
Authors: Kai Takeshi , Yokoya Akinari , Ukai Masatoshi , Fujii Kentaro , Toigawa Tomohiro , Watanabe Ritsuko
Published: January 2018

Although most of the radiation damage to genomic DNA could be rendered harmless using repair enzymes in a living cell, a certain fraction of the damage is persistent resulting in serious genetic effects, such as mutation induction.
On the approximation of independent pairs in diffusion kinetics: correlation of distances in a three-body system
Authors: Al-Samra Eyad H. , Green Nicholas J. B.
Published: January 2018

This study investigates the problem of diffusion kinetics in a three-body system, motivated by the theory of radiation chemical kinetics.
Solvation effects on the vibrational modes in hydrated bicarbonate clusters
Authors: Kong Xiangtao , Sun Shou-Tian , Jiang Ling , Liu Zhi-Feng
Published: January 2018

Harmonic analysis andab initiomolecular dynamics simulations reveal the solvation effects on the vibrational modes of HCO3−(H2O)n.
Photoelectrocatalytic effect of unbalanced RF magnetron sputtered TiO2 thin film on ITO-coated patterned SiO2 nanocone arrays
Authors: Choi Gyu Jin , Jung Hyemin , Kim Dong Ho , Sohn Youngku , Gwag Jin Seog
Published: January 2018

Highly increased photocurrent response of unbalanced RF magnetron sputtered TiO2 thin film on ITO-coated patterned SiO2 nanocone arrays.
Proton and oxygen ion conductivity in the pyrochlore/fluorite family of Ln2−xCaxScMO7−δ (Ln = La, Sm, Ho, Yb; M = Nb, Ta; x = 0, 0.05, 0.1) niobates and tantalates
Authors: Shlyakhtina A. V. , Pigalskiy K. S. , Belov D. A. , Lyskov N. V. , Kharitonova E. P. , Kolbanev I. V. , Borunova A. B. , Karyagina O. K. , Sadovskaya E. M. , Sadykov V. A. , Eremeev N. F.
Published: January 2018

The tolerance factor is a good criterion to understand the structural transitions in Ln2−xCaxScMO7−δ (M = Nb, Ta).
HOMEs for plants and microbes – a phenotyping approach with quantitative control of signaling between organisms and their individual environments
Authors: Siemianowski Oskar , Lind Kara R. , Tian Xinchun , Cain Matt , Xu Songzhe , Ganapathysubramanian Baskar , Cademartiri Ludovico
Published: January 2018

We enable the creation of model ecosystems constructed as physical networks of organisms by accelerating diffusion.
A new Zn(ii) metal–organic framework having 3D CdSO4 topology as luminescent sensor and photocatalyst for degradation of organic dyes
Authors: Jin Jun-Cheng , Wu Jian , Liu Wei-Cong , Ma Ai-Qing , Liu Jian-Qiang , Singh Amita , Kumar Abhinav
Published: January 2018

A new Zn(ii) metal–organic framework having 3D CdSO4 topology synthesized and deployed as a dual channel luminescent sensor for ferric ion and nitroaromatics, and a photocatalyst for the degradation of organic dyes.
Antiproliferative, antioxidant, computational and electrochemical studies of new azo-containing Schiff base ruthenium(ii) complexes
Authors: İnan Ayşe , İkiz Mesut , Tayhan Seçil Erden , Bilgin Sema , Genç Nusret , Sayın Koray , Ceyhan Gökhan , Köse Muhammet , Dağ Ayşe , İspir Esin
Published: January 2018

A new series of ruthenium(ii) complexes 7–11 containing the –NN– group are synthesized and characterized via elemental analysis, and IR, UV-visible and 1H–13C NMR spectroscopy.
Phytate–molybdate(vi) interactions in NaCl(aq)at different ionic strengths: unusual behaviour of the protonated species
Authors: Crea Francesco , De Stefano Concetta , Milea Demetrio , Sammartano Silvio
Published: January 2018

Stepwise stability constants of phytate/molybdate(vi) complexes regularly increase with the number of protons in the species, affecting their speciation and sequestration.
Selective adsorption of globulin on nanofiber meshes for immunoadsorption therapy
Authors: Kurimoto Rio , Namekawa Koki , Ellis Amanda V. , Naito Masanobu , Ebara Mitsuhiro
Published: January 2018

Cost-effective development of a carboxylated EVOH nanofiber mesh to adsorb γ-globulin selectively for immunoadsorption therapy.
Self-standing aptamers by an artificial defect-rich matrix
Authors: Chen Chong-You , Wang Chang-Ming , Chen Pai-Shan , Liao Wei-Ssu
Published: January 2018

The artificial defect-rich matrix provides inserted aptamers with “self-standing” orientation and an appropriate surface molecular environment for effective target recognition.
Construction of a quaternary ammonium salt platform with different alkyl groups for antibacterial and biosensor applications
Authors: Lv Xue , Liu Chuang , Song Shixin , Qiao Yun , Hu Yuanjiao , Li Pengfei , Li Zhaokun , Sun Shulin
Published: January 2018

The immobilized-protein in an appropriate alkyl chain length of DM displayed higher antibacterial activities, exhibited a more effective DET and a promising catalytic activity toward H2O2.
Polymer/oxide bilayer dielectric for hysteresis-minimized 1 V operating 2D TMD transistors
Authors: Yoon Minho , Ko Kyeong Rok , Min Sung-Wook , Im Seongil
Published: January 2018

By inserting hydroxyl-group free organic dielectric between hydrophilic oxide dielectric and 2D TMD channel, highly stable 2D FETs are achieved. This concept was successfully extended to a practical device application such as stable 1 V operation of 2D MoTe2 FET.
Evidence of electrostatic-enhanced depletion attraction in the structural properties and phase behavior of binary charged colloidal suspensions
Authors: Ojeda-Mendoza G. J. , Moncho-Jordá A. , González-Mozuelos P. , Haro-Pérez C. , Rojas-Ochoa L. F.
Published: January 2018

The addition of small charged particles to a dispersion of bigger charged colloids produces a depletion effect greater than that caused by the addition of neutral ones.
Stable DHLA–PEG capped PbS quantum dots: from synthesis to near-infrared biomedical imaging
Authors: Zamberlan F. , Turyanska L. , Patanè A. , Liu Z. , Williams H. E. L. , Fay M. W. , Clarke P. A. , Imamura Y. , Jin T. , Bradshaw T. D. , Thomas N. R. , Grabowska A. M.
Published: January 2018

Stability, biocompatibility and near-infrared photoluminescence of PbS nanocrystals capped with PEG-based ligands open up realistic prospects for non-invasive bioimaging applications.
Performance of Low-Income Dual Language Learners Attending English-Only Schools on the Clinical Evaluation of Language Fundamentals–Fourth Edition, Spanish
Authors: Barragan Beatriz , Castilla-Earls Anny , Martinez-Nieto Lourdes , Restrepo M. Adelaida , Gray Shelley
Published: January 2018

Purpose

The aim of this study was to examine the performance of a group of Spanish-speaking, dual language learners (DLLs) who were attending English-only schools and came from low-income and low-parental education backgrounds on the Clinical Evaluation of Language Fundamentals–Fourth Edition, Spanish (CELF-4S; Semel, Wiig, & Secord, 2006).

Method

Spanish-speaking DLLs (
N
= 656), ages 5;0 (years;months) to 7;11, were tested for language impairment (LI) using the core language score of the CELF-4S and the English Structured Photographic Expressive Language Test (Dawson, Stout, & Eyer, 2003). A subsample (
n
= 299) was additionally tested using a Spanish language sample analysis and a newly developed Spanish morphosyntactic measure, for identification of children with LI and to conduct a receiver operating characteristics curve analysis.

Results

Over 50% of the sample scored more than 1
SD
below the mean on the core language score. In our subsample, the sensitivity of the CELF-4S was 94%, and specificity was 65%, using a cutoff score of 85 as suggested in the manual. Using an empirically derived cutoff score of 78, the sensitivity was 86%, and the specificity was 80%.

Conclusions

Results suggest that the CELF-4S overidentifies low-income Spanish–English DLLs attending English-only schools as presenting with LI. For this sample, 1 in every 3 Latino children from low socioeconomic status was incorrectly identified with LI. Clinicians should be cautious when using the CELF-4S to evaluate low-income Spanish–English DLLs and ensure that they have converging evidence before making diagnostic decisions.
Invariant sets and controllability of discrete‐time bilinear systems
Authors: Tie Lin
Published: January 2018

In this study, the author investigates controllability of discrete‐time bilinear systems by using invariant sets. An invariant set defined in this study is a set on which the system is invariant, namely for any initial state that belongs to the set, the system cannot be steered away from this set. If a system is controllable, then it has no invariant set in its state space other than the state space itself. Invariant sets are thus closely related to controllability. By studying the invariant sets of discrete‐time bilinear systems, the author first presents a necessary and sufficient condition for controllability of the systems in dimension two, which covers a classical result under the same condition. Then the author considers the high‐dimensional systems and improve the recent results on controllability by relaxing a condition concerning invariant sets, where more general controllability criteria are derived. Finally, examples are given to illustrate the obtained results.
Direct self‐control strategy for brushless DC motor with reduced torque ripple
Authors: Xia Changliang , Chen He , Li Xinmin , Shi Tingna
Published: January 2018

This study proposed a direct self‐control (DSC) strategy with reduced torque ripple for brushless DC motor (BLDCM). Taking the inherent advantage of DSC, sensorless control can be easily achieved from the relationship between commutation points of BLDCM and the hexagon‐shape flux linkage locus. Furthermore, in the premise that position sensor is absent, excellent steady‐state torque performance can also be achieved by the proposed strategy, which is achieved by increasing the degrees of control freedom through translation of switching point. In addition, another attractive feature lies in its relatively simpler control structure. Detailed analysis of torque ripple is carried out by deriving the expressions of torque variation rate through solving differential equations. Durations of voltage vectors are calculated to ensure the minimisation of torque ripple. The superiority of the proposed method is confirmed by comparative experiments.
En route truck–drone parcel delivery for optimal vehicle routing strategies
Authors: Marinelli Mario , Caggiani Leonardo , Ottomanelli Michele , Dell'Orco Mauro
Published: January 2018

Recently, several prominent logistic companies in Europe and the USA are seriously considering the idea of using drones launched from trucks and working in parallel to deliver packages. In the relevant literature, a novel problem formulation called travelling salesman problem with drone has been introduced, and some modelling and solution approaches have been presented. Existing approaches are based on the main assumption that the truck can dispatch and pick up a drone only at a node, i.e. the depot or a customer location. Here, the authors present a novel approach aimed to maximise the drone usage in parcel delivering. The authors consider that a truck can deliver and pick a drone up not only at a node but also along a route arc (en route). In this way, the operations of a drone are not strictly related to the customers’ position, but it can serve a wider area along the route. The authors tested the proposed heuristic on benchmark instances and analysed the benefits introduced with the en route approach.
Achieving a minimum power fluctuation rate in wind and photovoltaic output power using discrete Kalman filter based on weighted average approach
Authors: Lamsal Dipesh , Sreeram Victor , Mishra Yateendra , Kumar Deepak
Published: January 2018

In this study, a discrete Kalman filter‐based approach is presented for minimising the output power fluctuations of wind and photovoltaic systems. The control strategy is based on the change in power fluctuation which is determined by the weighted average of the highest and lowest values of the power fluctuation for each interval of time. A genetic algorithm optimisation approach is utilised to determine the optimal value of weighted average such that the power fluctuation rate is minimum. This study also gives the optimum battery power and its state of charge to achieve smoothing determined by the optimal weighted average. On the basis of this optimum battery power, the specification and configuration of the battery energy storage system are also determined.
Dust models compatible with Planck intensity and polarization data in translucent lines of sight
Authors: Guillet V. , Fanciullo L. , Verstraete L. , Boulanger F. , Jones A. P. , Miville-Deschênes M.-A. , Ysard N. , Levrier F. , Alves M.
Published: January 2018

Context. Current dust models are challenged by the dust properties inferred from the analysis of Planck observations in total and polarized emission.

Aims. We propose new dust models compatible with polarized and unpolarized data in extinction and emission for translucent lines of sight (0.5 < AV < 2.5).

Methods. We amended the DustEM tool to model polarized extinction and emission. We fit the spectral dependence of the mean extinction, polarized extinction, total and polarized spectral energy distributions (SEDs) with polycyclic aromatic hydrocarbons, astrosilicate and amorphous carbon (a-C) grains. The astrosilicate population is aligned along the magnetic field lines, while the a-C population may be aligned or not.

Results. With their current optical properties, oblate astrosilicate grains are not emissive enough to reproduce the emission to extinction polarization ratio P353∕pV derived with Planck data. Successful models are those using prolate astrosilicate grains with an elongation a∕b = 3 and an inclusion of 20% porosity. The spectral dependence of the polarized SED is steeper in our models than in the data. Models perform slightly better when a-C grains are aligned. A small (6%) volume inclusion of a-C in the astrosilicate matrix removes the need for porosity and perfect grain alignment, and improves the fit to the polarized SED.

Conclusions. Dust models based on astrosilicates can be reconciled with Planck data by adapting the shape of grains and adding inclusions of porosity or a-C in the astrosilicate matrix.
The molecular chemistry of diffuse and translucent clouds in the line-of-sight to Sgr B2: Absorption by simple organic and inorganic molecules in the GBT PRIMOS survey
Authors: Corby J. F. , McGuire B. A. , Herbst E. , Remijan A. J.
Published: January 2018

The 1–50 GHz PRebiotic Interstellar MOlecular Survey (PRIMOS) contains ~50 molecular absorption lines observed in clouds located in the line-of-sight to Sgr B2(N). The line-of-sight material is associated with diffuse and translucent clouds located in the Galactic center, bar, and spiral arms in the disk. We measured the column densities and estimate abundances, relative to H2, of 11 molecules and additional isotopologues observed in this material. We used absorption by optically thin transitions of c-C3H2 to estimate the molecular hydrogen columns, and argue that this method is preferable to more commonly used methods. We discuss the kinematic structure and abundance patterns of small molecules including the sulfur-bearing species CS, SO, CCS, H2CS, and HCS+; oxygen-bearing molecules OH, SiO, and H2CO; and simple hydrocarbon molecules c-C3H2, l-C3H, and l-C3H+. Finally, we discuss the implications of the observed chemistry for the structure of the gas and dust in the ISM. Highlighted results include the following. First, whereas gas in the disk has a molecular hydrogen fraction of 0.65, clouds on the outer edge of the Galactic bar and in or near the Galactic center have molecular fractions of 0.85 and >0.9, respectively. Second, we observe trends in isotope ratios with Galactocentric distance; while carbon and silicon show enhancement of the rare isotopes at low Galactocentric distances, sulfur exhibits no trend with Galactocentric distance. We also determine that the ratio of c-C3H2/c-H13CCCH provides a good estimate of the 12C/13C ratio, whereas H2CO/H213CO exhibits fractionation. Third, we report the presence of l-C3H+ in diffuse clouds for the first time. Finally, we suggest that CS has an enhanced abundance within higher density clumps of material in the disk, and therefore may be diagnostic of cloud conditions. If this holds, the diffuse clouds in the Galactic disk contain multiple embedded hyperdensities in a clumpy structure, and the density profile is not a simple function of AV.
Short-term variability and mass loss in Be stars
Authors: Baade D. , Pigulski A. , Rivinius Th. , Carciofi A. C. , Panoglou D. , Ghoreyshi M. R. , Handler G. , Kuschnig R. , Moffat A. F. J. , Pablo H. , Popowicz A. , Wade G. A. , Weiss W. W. , Zwintz K.
Published: January 2018

Context. Be stars are important reference laboratories for the investigation of viscous Keplerian discs. In some cases, the disc feeder mechanism involves a combination of non-radial pulsation (NRP) modes.

Aims. We seek to understand whether high-cadence photometry can shed further light on the role of NRP modes in facilitating rotation-supported mass loss.

Methods. The BRITE-Constellation of nanosatellites obtained mmag photometry of 28 Cygni for 11 months in 2014–2016. We added observations with the Solar Mass Ejection Imager (SMEI) in 2003–2010 and 118 Hα line profiles, half of which were from 2016.

Results. For decades, 28 Cyg has exhibited four large-amplitude frequencies: two closely spaced frequencies of spectroscopically confirmed g modes near 1.5 c/d, one slightly lower exophotospheric (Štefl) frequency, and at 0.05 c/d the difference (Δ) frequency between the two g modes. This top-level framework is indistinguishable from η Cen (Paper I), which is also very similar in spectral type, rotation rate, and viewing angle. The circumstellar (Štefl) frequency alone does not seem to be affected by the Δ frequency. The amplitude of the Δ frequency undergoes large variations; around maximum the amount of near-circumstellar matter is increased and the amplitude of the Štefl frequency grows by a factor of a few. During such brightenings dozens of transient spikes appear in the frequency spectrum; these spikes are concentrated into three groups. Only 11 frequencies were common to all years of BRITE observations.

Conclusions. Be stars seem to be controlled by several coupled clocks, most of which are not very regular on timescales of weeks to months but function for decades. The combination of g modes to the slow Δ variability and/or the atmospheric response to it appears significantly non-linear. As in η Cen, the Δ variability seems to be mainly responsible for the modulation of the star-to-disc mass transfer in 28 Cyg. A hierarchical set of Δ frequencies may reach the longest known timescales of the Be phenomenon.
Characterization of Omega-WINGS galaxy clusters
Authors: Cariddi S. , D’Onofrio M. , Fasano G. , Poggianti B. M. , Moretti A. , Gullieuszik M. , Bettoni D. , Sciarratta M.
Published: January 2018

Context. Galaxy clusters are the largest virialized structures in the observable Universe. Knowledge of their properties provides many useful astrophysical and cosmological information.

Aims. Our aim is to derive the luminosity and stellar mass profiles of the nearby galaxy clusters of the Omega-WINGS survey and to study the main scaling relations valid for such systems.

Methods. We merged data from the WINGS and Omega-WINGS databases, sorted the sources according to the distance from the brightest cluster galaxy (BCG), and calculated the integrated luminosity profiles in the B and V bands, taking into account extinction, photometric and spatial completeness, K correction, and background contribution. Then, by exploiting the spectroscopic sample we derived the stellar mass profiles of the clusters.

Results. We obtained the luminosity profiles of 46 galaxy clusters, reaching r200 in 30 cases, and the stellar mass profiles of 42 of our objects. We successfully fitted all the integrated luminosity growth profiles with one or two embedded Sérsic components, deriving the main clusters parameters. Finally, we checked the main scaling relation among the clusters parameters in comparison with those obtained for a selected sample of early-type galaxies (ETGs) of the same clusters.

Conclusions. We found that the nearby galaxy clusters are non-homologous structures such as ETGs and exhibit a color–magnitude (CM) red-sequence relation very similar to that observed for galaxies in clusters. These properties are not expected in the current cluster formation scenarios. In particular the existence of a CM relation for clusters, shown here for the first time, suggests that the baryonic structures grow and evolve in a similar way at all scales.
2D wind clumping in hot, massive stars from hydrodynamical line-driven instability simulations using a pseudo-planar approach
Authors: Sundqvist J. O. , Owocki S. P. , Puls J.
Published: January 2018

Context. Clumping in the radiation-driven winds of hot, massive stars arises naturally due to the strong, intrinsic instability of line-driving (the line-deshadowing instability, hereafter LDI). But LDI wind models have so far mostly been limited to 1D, mainly because of the severe computational challenges regarding calculation of the multi-dimensional radiation force.

Aim. In this paper we simulate and examine the dynamics and multi-dimensional nature of wind structure resulting from the LDI.

Methods. We introduce a pseudo-planar, box-in-a-wind method that allows us to efficiently compute the line force in the radial and lateral directions, and then use this approach to carry out 2D radiation-hydrodynamical simulations of the time-dependent wind.

Results. Our 2D simulations show that the LDI first manifests itself by mimicking the typical shell structure seen in 1D models, but that these shells quickly break up into complex 2D density and velocity structures, characterized by small-scale density “clumps” embedded in larger regions of fast and rarefied gas. Key results of the simulations are that density variations in the well-developed wind are statistically quite isotropic and that characteristic length scales are small; a typical clump size is ℓcl∕R*~ 0.01 at 2R*, thus also resulting in rather low typical clump masses mcl ~ 1017 g. Overall, our results agree well with the theoretical expectation that the characteristic scale for LDI generated wind-structure is on the order of the Sobolev length ℓSob. We further confirm some earlier results that lateral “filling in” of radially compressed gas leads to somewhat lower clumping factors in 2D simulations than in comparable 1D models. We conclude by discussing an extension of our method toward rotating LDI wind models that exhibit an intriguing combination of large- and small-scale structures extending down to the wind base.
The host of the Type I SLSN 2017egm
Authors: Izzo L. , Thöne C. C. , García-Benito R. , de Ugarte Postigo A. , Cano Z. , Kann D. A. , Bensch K. , Della Valle M. , Galadí-Enríquez D. , Hedrosa R. P.
Published: January 2018

Context. Type I superluminous supernova (SLSN) host galaxies are predominantly low-metallicity, highly star-forming (SF) dwarfs. One of the current key questions is whether Type I SLSNe can only occur in such environments and hosts.

Aims. Here we present an integral-field study of the massive, high-metallicity spiral NGC 3191, the host of SN 2017egm, the closest Type I SLSN known to date. We use data from PMAS/CAHA and the public MaNGA survey to shed light on the properties of the SLSN site and the origin of star formation in this non-starburst spiral galaxy.

Methods. We map the physical properties of different H ii regions throughout the galaxy and characterise their stellar populations using the STARLIGHT fitting code. Kinematical information allows us to study a possible interaction with its neighbouring galaxy as the origin of recent star formation activity which could have caused the SLSN.

Results. NGC 3191 shows intense star formation in the western part with three large SF regions of low metallicity. Taking only the properties of emitting gas, the central regions of the host have a higher metallicity, a lower specific star formation rate, and lower ionisation. Modelling the stellar populations gives a different picture: the SLSN region has two dominant stellar populations with different ages, the younger one with an age of 2–10 Myr and lower metallicity, likely the population from which the SN progenitor originated. Emission line kinematics of NGC 3191 show indications of interaction with its neighbour MCG+08-19-017 at ~45 kpc, which might be responsible for the recent starburst. In fact, this galaxy pair has hosted a total of four SNe, 1988B (Type Ia), SN 2003ds (Type Ic in MCG+08-19-017), PTF10bgl (Type II), and 2017egm, underlying the enhanced SF in both galaxies due to interaction.

Conclusions. Our study shows that care should be taken when interpreting global host and even gas properties without looking at the stellar population history of the region. The SLSNe seem to be consistent with massive stars (>20 M⊙) requiring low metallicity (<0.6 Z⊙), environments that can also occur in massive late-type galaxies, but not necessarily with starbursts.
The [CII] 158 μm line emission in high-redshift galaxies
Authors: Lagache G. , Cousin M. , Chatzikos M.
Published: January 2018

Gas is a crucial component of galaxies, providing the fuel to form stars, and it is impossible to understand the evolution of galaxies without knowing their gas properties. The [CII] fine structure transition at 158 μm is the dominant cooling line of cool interstellar gas, and is the brightest of emission lines from star forming galaxies from FIR through metre wavelengths, almost unaffected by attenuation. With the advent of ALMA and NOEMA, capable of detecting [CII]-line emission in high-redshift galaxies, there has been a growing interest in using the [CII] line as a probe of the physical conditions of the gas in galaxies, and as a star formation rate (SFR) indicator at z ≥ 4. In this paper, we have used a semi-analytical model of galaxy evolution (G.A.S.) combined with the photoionisation code CLOUDY to predict the [CII] luminosity of a large number of galaxies (25 000 at z ≃ 5) at 4 ≤ z ≤ 8. We assumed that the [CII]-line emission originates from photo-dominated regions. At such high redshift, the CMB represents a strong background and we discuss its effects on the luminosity of the [CII] line. We studied the L[CII ]–SFR and L[ CII ]–Zg relations and show that they do not strongly evolve with redshift from z = 4 and to z = 8. Galaxies with higher [CII] luminosities tend to have higher metallicities and higher SFRs but the correlations are very broad, with a scatter of about 0.5 and 0.8 dex for L[ CII ]–SFR and L[ CII ]–Zg, respectively. Our model reproduces the L[ CII ]–SFR relations observed in high-redshift star-forming galaxies, with [CII] luminosities lower than expected from local L[ CII ]–SFR relations. Accordingly, the local observed L[ CII ]–SFR relation does not apply at high-z (z ≳ 5), even when CMB effects are ignored. Our model naturally produces the [CII] deficit (i.e. the decrease of L[ CII ]/LIR with LIR), which appears to be strongly correlated with the intensity of the radiation field in our simulated galaxies. We then predict the [CII] luminosity function, and show that it has a power law form in the range of L[ CII] probed by the model (1 × 107–2 × 109 L⊙ at z = 6) with a slope α = −1. The slope is not evolving from z = 4 to z = 8 but the number density of [CII]-emitters decreases by a factor of 20×. We discuss our predictions in the context of current observational estimates on both the differential and cumulative luminosity functions.
An overview of revenue management and dynamic pricing models in hotel business
Authors: Bandalouski Andrei M. , Kovalyov Mikhail Y. , Pesch Erwin , Tarim S. Armagan
Published: January 2018

Basic concepts and brief description of revenue management models and decision tools in the hotel business are presented. An overview of the relevant literature on dynamic pricing, forecasting methods and optimization models is provided. The main ideas of the authors’ customized revenue management method for the hotel business are presented.