bluuebunny/crossref_metadata_2025 huggingface dataset:
Tissue-specific evaluation of suitable reference genes for RT-qPCR in the pond snail,Lymnaea stagnalis
Authors: Young Alexander P. , Landry Carmen F. , Jackson Daniel J. , Wyeth Russell C.
Published: October 2019

Reverse transcription quantitative PCR (RT-qPCR) is a robust technique for the quantification and comparison of gene expression. To obtain reliable results with this method, one or more reference genes must be employed to normalize expression measurements among treatments or tissue samples. Candidate reference genes must be validated to ensure that they are stable prior to use in qPCR experiments. The pond snail (Lymnaea stagnalis) is a common research organism, particularly in the areas of learning and memory, and is an emerging model for the study of biological asymmetry, biomineralization, and evolution and development. However, no systematic assessment of qPCR reference genes has been performed in this animal. Therefore, the aim of our research was to identify stable reference genes to normalize gene expression data from several commonly studied tissues inL. stagnalisas well as across the entire body. We evaluated a panel of seven reference genes across six different tissues inL. stagnaliswith RT-qPCR. The genes included:elongation factor 1-alpha,glyceraldehyde-3-phosphate dehydrogenase,beta-actin,beta-tubulin,ubiquitin,prenylated rab acceptor protein 1, and a voltage gated potassium channel. These genes exhibited a wide range of expression levels among tissues. The tissue-specific stability of each of the genes was consistent when measured by the standard stability assessment algorithms: geNorm, NormFinder, BestKeeper, and RefFinder. Our data indicate that the most stable reference genes vary among the tissues that we examined (central nervous system, tentacles, lips, penis, foot, mantle). Our results were generally congruent with those obtained from similar studies in other molluscs. Given that a minimum of two reference genes are recommended for data normalization, we provide suggestions for strong pairs of reference genes for single- and multi-tissue analyses of RT-qPCR data inL. stagnalis.
ncRNA2MetS: a manually curated database for non-coding RNAs associated with metabolic syndrome
Authors: Yao Dengju , Zhan Xiaojuan , Zhan Xiaorong , Kwoh Chee Keong , Sun Yuezhongyi
Published: October 2019

Metabolic syndrome is a cluster of the most dangerous heart attack risk factors (diabetes and raised fasting plasma glucose, abdominal obesity, high cholesterol and high blood pressure), and has become a major global threat to human health. A number of studies have demonstrated that hundreds of non-coding RNAs, including miRNAs and lncRNAs, are involved in metabolic syndrome-related diseases such as obesity, type 2 diabetes mellitus, hypertension, etc. However, these research results are distributed in a large number of literature, which is not conducive to analysis and use. There is an urgent need to integrate these relationship data between metabolic syndrome and non-coding RNA into a specialized database. To address this need, we developed a metabolic syndrome-associated non-coding RNA database (ncRNA2MetS) to curate the associations between metabolic syndrome and non-coding RNA. Currently, ncRNA2MetS contains 1,068 associations between five metabolic syndrome traits and 627 non-coding RNAs (543 miRNAs and 84 lncRNAs) in four species. Each record in ncRNA2MetS database represents a pair of disease-miRNA (lncRNA) association consisting of non-coding RNA category, miRNA (lncRNA) name, name of metabolic syndrome trait, expressive patterns of non-coding RNA, method for validation, specie involved, a brief introduction to the association, the article referenced, etc. We also developed a user-friendly website so that users can easily access and download all data. In short, ncRNA2MetS is a complete and high-quality data resource for exploring the role of non-coding RNA in the pathogenesis of metabolic syndrome and seeking new treatment options. The website is freely available at http://www.biomed-bigdata.com:50020/index.html
Gross chemical composition, fatty acids, sterols, and pigments in tropical seaweed species off Sinaloa, Mexico
Authors: Osuna-Ruiz Idalia , Nieves-Soto Mario , Manzano-Sarabia Mercedes Marlenne , Hernández-Garibay Enrique , Lizardi-Mendoza Jaime , Burgos-Hernández Armando , Hurtado-Oliva Miguel Ángel
Published: October 2019

Biochemical composition was assessed in green (Ulva expansa, Caulerpa sertularioides, Rhizoclonium riparium, Codium isabelae), red (Spyridia filamentosa, Gracilaria vermiculophylla), and brown (Padina durvillaei) seaweeds collected from different tropical lagoons on the Pacific coast of Sinaloa, Mexico. Protein content was higher in C. sertularioides, S. filamentosa, and G. vermiculophylla (10–12%), followed by R. riparium, P. durvillaei, and U. expansa (8%, 6%, and 4%, respectively). Lipid content was in the range of 0.3–1.5%, with the highest value found in R. riparium. The highest content of nitrogen-free extract (i.e., carbohydrates) (69%) and the lowest ash value (25%) were assessed in P. durvillaei. Polyunsaturated fatty acid content was in the range of 5–45%, with higher values in R. riparium (45%), C. sertularioides (39%), and P. durvillaei (23%). Red seaweeds showed the highest value of cholesterol+dehydrocholesterol (>90%), while green seaweeds showed the highest contents of β-sitosterol (71–77%), except for U. expansa, for which fucosterol+isofucosterol (79%) was highest. Pigment composition was different among seaweeds but coincided with previous reports. The biochemical components used as biomarkers were assessed by principal component analysis to discriminate among assessed variables and to cluster seaweed species according to the common variability of their biochemical composition. Results showed that composition was similar within seaweed divisions but particularly different in U. expansa and P. durvillaei. Biochemical compounds that contributed to total variability were β-sitosterol, 20:4n-6, 20:5n-3, chlorophyll a and b, and β-carotene, and to a lesser extent fucosterol+isofocusterol and 22:6n-3. Results showed that the analyzed seaweed species may be useful for animal nutrition and appropriate for human consumption.
Paleoceanographic and paleoclimatic reconstruction based on marine palynomorphs in the period 1811–1907 CE in the Magdalena Basin, Baja California Sur, Mexico
Authors: López-Velázquez Laura Cristina , Helenes Javier , Flores-Trujillo Juan Gabriel , Ruiz-Fernández Ana Carolina , Sanchez-Cabeza Joan Albert
Published: October 2019

Biennial variations of marine palynomorph concentrations mirrored oceanographic conditions in the Magdalena Basin, Baja California Sur (Mexico), in the period from 1811 to 1907 (common era, CE), for which the sea surface temperature index (SSTI) showed predominantly negative anomalies. We analyzed 49 samples of laminated sediments taken from a core extracted at a water depth of 520 m. Changes in dinoflagellate assemblages and copepod egg abundances were compared to SSTI records and to El Niño Southern Oscillation (ENSO) and Pacific Decadal Oscillation (PDO) reconstructions. Copepods were the most abundant and showed a significant correlation with SSTI. Among the dinoflagellates, heterotrophs were the most abundant and did not correlate with SSTI. The lowest concentration of autotrophs showed a significant and inverse correlation with SSTI. The canonical correlation analysis also indicated that copepods and autotrophs were modulated by variations in SSTI. Dinoflagellate richness and concentrations and copepod egg concentrations were low, indicating low productivity, and these values coincided with the negative SSTI anomalies. In contrast, the increase in concentrations from 1881 to 1907 CE coincided with positive SSTI anomalies. Also, even when marine palynomorphs showed no significant correlation with either ENSO or PDO, their concentrations increased during age intervals with combined negative conditions (La Niña, negative PDO) and decreased during combined warm conditions (El Niño, positive PDO).
The Effect of Background on Students’ Interest in Mathematics: The Mediation of Students’ Motivation and Perception in Ghana
Authors: Arthur Yarhands Dissou
Published: October 2019

The dependence of scientific and technological advancement on mathematics requires investigation into what affects students’ motivation in mathematics. The present study investigated the influence of students’ background (SB) as mediated by students’ perception (SP), and students’ motivation (SM) as predictor of students’ interest in mathematics (SIM). The study further presented an empirical structural equation models (SEM) that predicts students’ interest, students’ motivation and students’ perception in mathematics. Using cohort samples of randomly selected 1,263, participants completed researcher-designed and validated questionnaires with a-reliability of 0.74, 0.7, 0.68, 0.82 and 0.94 for SIM, SB, SM, SP and overall instrument reliability respectively. The results from the study at 5% alpha level indicated as statistically significant relationship between SP, SB, SM and SIM. SP, SB, SM explain 27.9% of variance in SIM. The study further revealed statistical significance between SB and SP such that SB explains 32.1%, of variance in SP. The study finally established statistically significant relationship between SB, SP and SM; the study confirms that SB and SP explain 31.6% of SM. The study concluded that students’ interest in mathematics is related to student perception, students’ background, and students’ motivation. It was further concluded that student motivation is related to students’ perceptions and students’ background. Finally, although students’ background predicts students’ perception about mathematics. It is recommended to educators and educational stakeholders to focus attention on determinants of students’ mathematics interest by introducing positive interventions from the very beginning of students’ mathematics education.
Ethnobotanic Survey of Aids Opportunistic Infections in the Ziguinchor District, Sénégal
Authors: Diatta Kady , Diatta William , Dior Fall Alioune , Mbacké Dieng Serigne Ibra , Mbaye Amadou Ibrahima , Manga Idrissa
Published: October 2019

HIV / AIDS infection is characterized by the reduction of the body's defenses favoring the occurrence "opportunistic" infections, as bronchitis, mycoses and tuberculosis etc. Thus, to fight against this virus, antiretrovirals are used.

The Ziguinchor district (Senegal) has a higher seroprevalence rate of 2.2% above the national average of 0.7%. It is in this sense that a survey of two herbalists, 35 tradipraticians and eight resource persons was conducted to identify the plants used in the management of opportunistic AIDS diseases because as the populations often resort to phytotherapy. 88 plants were identified and divided into 79 genera and 38 families. Some species were mentioned very more frequently and in many diseases. These are: Cordila pinnata Poir. (78%), Guiera senegalensis (73.1%), Khaya senegalensis (67%), Icacina oliviformis (55%), Terminalia macroptera (55%), Cassia sieberiana (47%), etc. Leaves and roots constituted the greatest use in the form of macerated, infused, for drinking, bathing, or fumigation, etc. The expected result during this study was the establishment of a repertory of medicinal plants used for the management of opportunistic diseases.
From Two to One Index Isomorphism in Optimization Program for Quarterly Disaggregation of Annual Times Series
Authors: Essessinou Raïmi Aboudou , Degla Guy , Ndiaye Babacar Mbaye
Published: October 2019

The quarterly disaggregation of an annual economic aggregate, by a mathematical method with a cyclical indicator, gives rise to a problem of minimization to make the quarterly economic aggregate smooth. This involves two indexes for the quarter and the year, which sometimes can make the resolution algorithm less efficient if the problem is large. In this paper we propose a method of indexing quarterly variables based on an isomorphic transformation of a two-index program into a one-index program, in order to minimize the cost of the algorithm of resolution. This method of continuous indexing of variables, applied to national accounts, shows that the algorithm with a single index is more efficient than the algorithm with two indexes when solving the optimization program of the quarterly disaggregation.
Angulating Social and Environmental Reporting to Firms’ Advantage: A Resource Based View Approach from Ethiopian Companies’ Perspective
Authors: Surur Sitina Akmel , Yimenu Kirubel Asegdew , Baje Kasu Birbirsa
Published: October 2019

Aims: To evaluate the strategic role of social and environmental reporting in Ethiopian large tax payer companies based on the resource-based view of the firm.

Study Design: The study employed explanatory research design.

Place and Duration of Study: Large tax payer companies for the year 2018, Ethiopia.

Methodology: The study used annual audited financial reports of 262 companies and structured questionnaire which were distributed to three individuals per each sampled company. Interaction effect model was developed for which ordinary least square (OLS) regression with robust standard errors on a cross-sectional analysis were used to test the hypotheses.

Results: The regression result showed that social & environmental reporting and the interaction effect of social & environmental reporting with companies’ environmental sensitivity had significant positive impact on reputability of companies.

Conclusion: The study concluded that through social and environmental reporting, companies can develop valuable resource which in turn increase their reputability. Hence, environmental sensitive companies have more operational negative effect to society and environment, they are considered as dangerous by the society. Heretofore, these companies can strategically shift this perception to companies’ advantage through social and environmental reporting.

Originality/Value: In the availability of limited studies which explore social and environmental reporting practice within developing country perspective, this study shed some light about the Ethiopian companies reporting practice. Furthermore, the results of this study were an indication for companies’ managers to strategically use social and environmental reporting, which in turn increase their reputability and prevent them from being perceived as dangerous by the society.
Hydroethanolic Extract of Buchholzia coriacea Seeds Alleviates LPS Induced Liver Injury in Rat via Antioxidant and Anti-inflammatory Actions
Authors: Ore Ayokanmi , Ugbaja Regina Ngozi , Adeogun Abideen Idowu , Akinloye Oluseyi Adeboye
Published: October 2019

Aim: This study evaluates the hepatoprotective effects of hydroethanolic extract of (defatted) Buchholzia coriacea seed (HEBCS) against lipopolysaccharide (LPS) induced inflammatory liver injury in the rat.

Method: Thirty male albino rats (120–130 g) were assigned into five groups (n=6/ group). Group I (Control) and II (LPS) received distilled water orally (p.o.) for seven days while animals in groups III, IV and V were administered HEBCS at 125, 250 and 500 mg/kg body weight (b.w.) p.o. daily for 7 days. LPS was injected on the 7th day at a single dose of 4 mg/kg intraperitoneally (i.p.) to the rats in group II, and groups III, IV and V. Six hours after LPS injection, blood was collected to prepare serum, and liver was removed for preparation of homogenate, histopathology and immunofluorescence staining. Biomarkers of liver function (ALT, AST and ALP) and oxidative stress (NO, SOD, CAT and MDA) were assessed. Pro-inflammatory cytokine (TNF-α) and inducible protein (C-reactive protein) were also assessed.

Results: Results showed significant amelioration of liver function markers and levels of pro-inflammatory proteins by HEBCS. Histopathological studies showed a reduction in inflammatory cells and improvement in liver structure in animals treated with HEBCS.

Conclusion: Data from the current study show that HEBCS possesses hepatoprotective effects against LPS induced inflammatory liver injury.
Preserved Memory Function of Rats Following Fluorouracil Treatment
Authors: Alhowail Ahmad H.
Published: October 2019

Chemotherapy is widely used to treat cancers, but can have undesirable secondary effects, such as cognitive impairment. Fluorouracil (5-FU) is a chemotherapeutic agent that is combined with other agents to treat different types of cancer, such as breast, prostate and brain cancer. 5-FU has been reported to pass the blood–brain barrier, but its effects on cognition are not yet well established. The aim of this study was to evaluate the effects of 5-FU on memory function. 5-FU was injected intraperitoneally into rats. 5-FU did not impair memory function determined using the Y-maze and novel object recognition behavioral tests. Therefore, it is concluded that fluorouracil itself does not induce the memory impairment of chemobrain.
Inovação Através da Educação e Pesquisa: O Caso Chinês
Authors: Sichel Debora Lacs , Magalhães Gabriel Ralile de Figueiredo
Published: October 2019

O presente artigo busca tratar da relação entre educação, pesquisa, inovação e desenvolvimento. O caso abordado é a China uma vez que grande parte do investimento em seu sistema nacional de educação e articulação com os demais setores produtivos, conseguiu gerar tanto uma maior competitividade interna, como internacional. O trabalho se estrutura na análise da evolução histórica do sistema educacional chinês e de seu setor de P&D, para isso se valendo das patentes e publicações científicas como unidades de mensuração. Por fim, o estudo conclui da importância da educação e da pesquisa para o aperfeiçoamento do sistema nacional de inovação de um país e de seu consequente desenvolvimento.
Enzyme Evolution
Authors: Sanchez‐Ruiz Jose M
Published: October 2019

Life involves an enormous diversity of coupled chemical reactions, almost none of which would occur in a biologically relevant time scale without catalysis. Enzymes are life catalysts, capable of enhancing the rates of biochemical reactions by many orders of magnitude. Modern natural enzymes are the complex outcome of evolution operating over a vast expanse of time. Plausibly, the overall process started ∼4 billion years ago when polypeptides that possibly served as cofactors of ribozymes in the RNA world acquired the capability to catalyse simple reactions. Likely, primordial enzymes were generalists that could catalyse various reactions with moderate efficiency. Diversification, specialisation and optimisation occurred subsequently over evolutionary history, probably coupled to successive gene duplication events. Advances in protein engineering and laboratory evolution have allowed some of the main stages in this evolutionary narrative to be reproduced in the laboratory and have demonstrated the fundamental role of conformational diversity in enzyme evolution.

Key Concepts

Modern natural enzymes are the complex outcome of evolution operating over ∼4 billion years.

Most modern natural enzymes evolved from previously existing enzymes.

To avoid detrimental effects on organismal fitness, the emergence of new enzymes from old enzymes is likely coupled to gene duplication.

Directed evolution experiments allow the transformation of an old enzyme into a new enzyme to be reproduced in the laboratory.

The evolutionary transformation of an old enzyme into a new enzyme likely occurs trough multifunctional intermediates.

Unless we accept panspermia as an explanation for the origin of life on Earth, we must admit that, at some very early stage of life evolution on this planet, primordial enzymes emergedde novoin noncatalytic scaffolds.

Recent work has shown that single mutations can generate emerging enzyme functionalities in previously noncatalytic scaffolds.

Proteins in solution are best envisioned as ensembles of different conformations.

Experimental and computational studies support that conformational diversity underlies enzyme ‘evolvability’, that is, the capability to evolve towards new functionalities.

Our current understanding of enzyme evolution is not detailed enough to provide a reliable basis for rational enzyme design.
Thermithiobacillus
Authors: Boden Rich , Hutt Lee P.
Published: October 2019

Ther.mi.thi.o.ba.cil'lus. L. fem. n.therma, a warm or hot bath; Gr. neut. n.theîon, sulfur, brimstone (transliterated to L. neut. n.thium); L. masc. n.bacillus, a short rod, a short wand; N.L. masc. n.Thermithiobacillus, sulfur rodlet from a warm bath, or warm sulfur rodlet.

Proteobacteria / Acidithiobacillia / Acidithiobacillales / Thermithiobacillaceae / Thermithiobacillus

Cells are short, rapidly motile rods with a single polar flagellum, which can be 3–6 times longer than the cell. Gram‐stain‐negative. Endospores, exospores, and cysts are not produced. Obligate chemolithoautotrophs, using reduced inorganic sulfur species such as thiosulfate, polythionates, elementary sulfur (viz.α‐S8), and sometimes hydrogen sulfide, bisulfide, or d‐ or p‐block sulfide minerals such as galena (PbS). Heterotrophy, methylotrophy, and the so‐called C1autotrophy are not observed. Carbon assimilated from CO2via the transaldolase variant of the Calvin–Benson–Bassham cycle. Carboxysomes are used for CO2concentration. No vitamin auxotrophy. Obligately respiratory, with molecular oxygen as the only known terminal electron acceptor, though nitrate is reduced to nitrite under air. Usually isolated from environments with high Ca2+and/or Mg2+ions. Usually has a high tolerance to Mg2+ions. Most strains grow in the range of 20–52 °C, though some have a narrower range, and from pH 4.0–5.5 to pH 8.0–8.7. Most strains grow best without NaCl, but for one strain, the optimum is 350 mM (2% w/v). The major respiratory quinone is ubiquinone‐8 (UQ‐8). Dominant fatty acids in thiosulfate‐grown cells are usually palmitic acid (C16:0), palmitoleic acid (C16:1), vaccenic acid (C18:1), and ω‐cyclohexylmargaric acid (C17:0cyclo). The dominant polar lipids in the same cells are cardiolipin, phosphatidylethanolamine, phosphatidylglycerol, and aminoglycolipids. The G + C fraction of genomic DNA is around 58.5–67.0 mol%. Form IAc (carboxysomal) and Form IC (cytoplasmic)d‐ribulose 1,5‐bisphosphate carboxylase/oxygenase are used, as are formsaa3andcbb3cytochromecoxidase and thebd‐I ubiquinol oxidase.

DNA G+C content (mol%): 58.5–67.0.

Type species:Thermithiobacillus tepidarius(Wood and Kelly 1985) Kelly and Wood 2000, 515VP(Thiobacillus thioparusWood and Kelly 1985, 436).
Unique Role of Arginine in Positively‐Charged Surface for Promotion of Antibacterial and Osteogenetic Capabilities
Authors: Zhang Wei , Liu Jun , Yang Kun , Qu Wei , Liu Ke , Liu Na , Gu Bin , Hu Nan , Ji Junhui , Chu Paul K. , Wang Huaiyu
Published: October 2019

Orthopedic implants made of titanium and titanium alloys are vulnerable to invasion of pathogenic bacteria and hence, it is desirable to endow implants with the antibacterial capability to mitigate postsurgical infection and other undesirable side‐effects. In this study, arginine is combined with polyhexamethylene biguaidine hydrochloride (PHMB) to fabricate an antibacterial coating on titanium samples. As arginine with the guanidinium form is similar to PHMB, the coating is positively‐charged and delivers excellent antibacterial performance due to the high surface potential. Furthermore, arginine is a natural α‐amino acid being friendlier to tissues than PHMB and the coating delivers good osteogenetic performance in vitro and in vivo in addition to a low level of inflammatory response. The combination of cationic arginine and PHMB enhances the antibacterial and osteogenetic functions simultaneously and suggests clinical potential.
Ethyl acetate as a bio‐based solvent to reduce energy intensity and CO2 emissions of in situ bitumen recovery
Authors: Zirahi Ali , Sadeghi Yamchi Hassan , Haddadnia Ali , Zirrahi Mohsen , Hassanzadeh Hassan , Abedi Jalal
Published: October 2019

We introduce ethyl acetate (EA), a bio‐based chemical, as a potential solvent for bitumen recovery through comprehensive phase behavior and numerical simulation studies. Phase behavior and thermophysical properties of EA/live bitumen are measured at temperatures and pressures up to 190°C and 4 MPa, respectively. Experimental studies suggested that coinjection of EA with steam can reduce the bitumen viscosity by several orders of magnitude. Our numerical simulations show that coinjection of 2–8 mol% EA with steam can significantly reduce the steam‐oil‐ratio (SOR) by almost 0.9 units while increasing the bitumen production rate. This reduction in SOR can be translated to significant energy saving of ~2.2 GJ, emission reduction of ~120 kg of CO2, and wastewater reduction of ~120 m3 per ton of the produced bitumen, which are almost 20–25% lower than the steam‐assisted gravity drainage (SAGD) process.
Enhanced modification technique for polyacrylonitrile UF membranes by direct hydrolysis in the immersion bath
Authors: Cheraghali Reihaneh , Maghsoud Zahra
Published: October 2019

Conventional hydrolysis modification of polyacrylonitrile (PAN) membranes is usually carried out in a post‐treatment step during which hydrophilic groups are created on the membrane surface. In this article, however, direct hydrolysis in the immersion bath is proposed as a new and simple approach for simultaneous membrane preparation and modification. The main advantages of this method include lower alkali concentrations, promptness, and the lack of need for elevating temperature compared to other studies. The cast films were immersed in the coagulation bath containing aqueous NaOH solutions of various concentrations (0.003, 0.0125, 0.025, 0.05, and 0.1 M) for 1, 3, 5, and 10 min, which were then transferred to a bath of pure water. Membranes were characterized by pure water flux, porosity, average pore diameter, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), atomic force microscopy (AFM), contact angle, mechanical properties, rejection, and flux recovery ratio (FRR) measurements. At all treatment times, the pure water flux of modified membranes reached its maximum at low NaOH concentrations with a substantial increase (210%) in the membrane treated with 0.0125 M NaOH for 1 min. Furthermore, the kinetics of the hydrolysis reaction was considered to provide deeper insights into morphological changes occurring during the hydrolysis. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48583.
Study on the performance of syntactic foam reinforced by hybrid functionalized carbon nanotubes
Authors: Ya Bin , Wang Yaosheng , Meng Linggang , Zhou Bingwen , Zhang Xingguo
Published: October 2019

Hollow glass microspheres (HGMs)/epoxy syntactic foam were reinforced by hybrid functionalized carbon nanotubes that were synthesized by simultaneous covalent and noncovalent functionalization of carbon nanotubes. The effect of hybrid functionalized carbon nanotubes on density, mechanical properties, and water absorption of HGMs/epoxy syntactic foam was studied. The study indicated that the dispersion of carbon nanotubes in epoxy resin can be improved by hybrid functionalization. The compression strength of syntactic foam reinforced by hybrid functionalized carbon nanotubes was significantly enhanced. The maximum compressive strength of syntactic foam corresponding to chitosan modified carbon nanotubes approached 60 MPa. Hybrid functionalized carbon nanotubes had little effect on the water absorption ability of syntactic foam, and was less than 1%. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48586.
Tidal disruption events as a site of an evolving relativistic spectral line
Authors: Štolc Marcel , Karas Vladimír
Published: October 2019

In nuclei of galaxies, strong tidal forces can destroy stars passing within a critical distance from the central supermassive black hole (SMBH). Observational signatures of tidal disruption events (TDEs) depend on the environment around the SBMH horizon and the level of its accretion activity. Evidence for optical and ultraviolet spectral features has been reported in TDE flares; nevertheless, to test the effects of general relativity in the immediate vicinity of SMBH, the relativistically broadened and skewed X‐ray line would tell us significantly more useful information. This will require to proceed beyond inactive nuclei. To this end, we consider a system where the material from a disrupted star forms a gaseous ring that circularizes near the tidal radius around SMBH, it gradually spreads in radius by viscous processes and resides embedded within a hot corona. In our test calculation, the remnant trail is assumed to be fully circularized and embedded in a hot environment and illuminated by X‐rays from a surrounding corona or a jet base of (mild) active galactic nucleus activity. We show the expected effects on the observed profile and the centroid energy. In the future, the evolving spectral features can enhance the diagnostic capability and provide a novel way to reveal the parameters of TDEs in such sources; the distance of the remnant gas from the SMBH, the radial extent of the gaseous trail, and the spin of the SMBH could be measured.
Methods for identifying high‐redshift galaxy cluster candidates
Authors: Pinter Sandor , Balázs Lajos G. , Bagoly Zsolt , Horvath Istvan , Rácz István I. , Tóth Viktor L.
Published: October 2019

Recent theories linked long gamma ray bursts (GRBs) to galaxies with rapid star formation or starburst; thus, we expect that long GRBs (LGRBs) are more frequent in midcluster galaxies where mergers and tidal interactions between gas‐rich galaxies are more likely to occur. Yet there is no galaxy cluster known to be associated with LGRBs. We demonstrate that, based on deep, single‐band Subaru Hyper Suprime‐Cam observations, we may provide constraints on photometric redshifts of groups of galaxies. We compare three methods: cosmological approach, pseudoinverse matrix, and random forests to estimate galaxy and quasar redshifts. Comparing our results to spectroscopic redshifts of Sloan Digital Sky Survey's‐detected extragalactic sources, random forests may provide the highest accuracy with as low as 17 percentage error. This is a powerful method to find clusters to place GRB host galaxies in their local environment.
Predicting Potential Inversion Behavior of Ru–aqua Complexes via Using Cost Effective DFT Calculations
Authors: Kim Moon Ju , Kang Youn K.
Published: October 2019

Since the potential inversion behavior of a Ru–aqua complex during the sequential, proton‐coupled, two‐electron oxidations, RuII─OH2 → RuIVO via RuIII─OH, has been experimentally confirmed, the calculation method for predicting this phenomenon becomes necessary for the rational design of such complexes. Here, we devise cost‐effective calculation protocols that properly describe sequential, proton‐coupled, two‐electron oxidation reactions. The suggested protocols are: (1) by use of an mPW1LYP hybrid functional coupled with a LANL2DZ basis set with an effective core potential (ECP) for transition metal, and a 6‐31g(d) basis set for the rest of atoms; and (2) by use of a PBE1PBE hybrid functional with a def2SVP basis set for all atoms, and an Stuttgart RSC 1997 ECP for transition metal. With these protocols, we demonstrated that a Meyer–Lever plot of six representative Ru–aqua complexes, in which atoms of the ligands are second‐row elements, can be satisfactorily reproduced.
The Tissue‐Supported Sling Suture: Technique and Clinical Applications
Authors: McGary Ryan T. , Johnson Thomas M. , Berridge Joshua P. , Wilson James P. , Baron Dmitry
Published: October 2019

Introduction

Continuous and interrupted sling sutures (ISSs) are used around teeth in contemporary periodontics. However, conventional ISSs depend upon favorable tooth morphology for stability through the early healing period. The purpose of this report is to present a variation of the classic ISS that does not rely on favorable tooth morphology.

Case Series

Tissue‐supported sling sutures (TSSs) were used for six patients undergoing root coverage, gingival augmentation, or pontic site development (guided bone regeneration) procedures.

Conclusions

Although techniques such as vertical mattress suturing may support greater coronal flap advancement, the TSS technique does maintain coronal flap position while minimizing trauma to papillae. TSS stability is independent of tooth morphology and may offer clinicians flexibility in achieving reliable closure over hard and soft tissue implants. Like mattress sutures, TSSs reduce tension at the crestal incision line in tissue grafting procedures.
Scavenging Bacterial Siderophores with Engineered Lipocalin Proteins as an Alternative Antimicrobial Strategy
Authors: Dauner Martin , Skerra Arne
Published: October 2019

Iron acquisition mediated by siderophores, high‐affinity chelators for which bacteria have evolved specific synthesis and uptake mechanisms, plays a crucial role in microbiology and in host–pathogen interactions. In the ongoing fight against bacterial infections, this area has attracted biomedical interest. Beyond several approaches to interfere with siderophore‐mediated iron uptake from medicinal and immunochemistry, the development of high‐affinity protein scavengers that tightly complex the siderophores produced by pathogenic bacteria has appeared as a novel strategy. Such binding proteins have been engineered based on siderocalin—also known as lipocalin 2—an endogenous human scavenger of enterobactin and bacillibactin that controls the systemic spreading of commensal bacteria such as Escherichia coli. By using combinatorial protein design, siderocalin was reshaped to bind several siderophores from Pseudomonas aeruginosa and, in particular, petrobactin from Bacillus anthracis, none of which is recognized by the natural protein. Such engineered versions of siderocalin effectively suppress the growth of corresponding pathogenic bacteria by depriving them of their iron supply and offer the potential to complement antibiotic therapy in situations of acute or persistent infection.
Towards Stable and Conductive Titanium Oxynitride High‐Surface‐Area Support for Iridium Nanoparticles as Oxygen Evolution Reaction Electrocatalyst
Authors: Bele Marjan , Stojanovski Kevin , Jovanovič Primoz , Moriau Leonard , Koderman Podboršek Gorazd , Moškon Jože , Umek Polona , Sluban Melita , Dražič Goran , Hodnik Nejc , Gaberšček Miran
Published: October 2019

The front cover artwork for Issue 20/2019 is a collaboration between the National Institute of Chemistry (Slovenia) and the Jožef Stefan Institute (Slovenia). The image shows titanium oxynitride nanoribbons with finely dispersed iridium nanoparticles as an oxygen evolution reaction electrocatalyst. See the Full Paper itself at https://doi.org/10.1002/cctc.201901487.
PV‐betriebene Umkehrosmoseanlage zur Meerwasserentsalzung – Modellierung und Analyse verschiedener Energieversorgungsvarianten
Authors: Sanna Anas , Kaltschmitt Martin , Ernst Mathias
Published: October 2019

Die Umkehrosmose ist eine sehr energieeffiziente Option zur Meerwasserentsalzung. Da sie nur elektrische Energie nachfragt, bietet sich aus Klimaschutzgründen eine Kombination von Umkehrosmose‐ und Photovoltaik(PV)‐Anlagen an. Deshalb wird hier eine PV‐basierte Umkehrosmose‐Anlage zur Meerwasserentsalzung für einen Standort in Saudi‐Arabien ausgelegt und modelliert. Ausgehend davon werden verschiedene Varianten einer PV‐versorgten Meerwasserentsalzungsanlage untersucht und daraus Schlussfolgerungen für den Bau derartiger Anlagen abgeleitet.
Entrapment, positive psychological functioning and suicide ideation: A moderation analysis
Authors: Teismann Tobias , Brailovskaia Julia
Published: October 2019

The Integrated Motivational–Volitional (IMV) Model of suicide posits that the association between perceptions of entrapment and suicide ideation is buffered by so‐called motivational moderators. The present study investigated, whether positive mental health as well as different facets of psychological well‐being qualify as motivational moderators. Possible moderator effects were investigated in an online sample (N = 301). Results demonstrated that positive mental health and psychological well‐being moderate the association between entrapment and suicide ideation. These findings underscore the importance of entrapment and positive psychological functioning in understanding pathways to suicide ideation.
Experimental research on leaf vein geometric characteristics of multibranch horizontal well for coalbed methane recovery
Authors: Guo Xiaoyang , Deng Cunbao , Fan Yongpeng , Mu Yongliang , Fan Nan
Published: October 2019

The similarity in the structure and function between leaf veins and multibranch wells provided the inspiration for a novel design of multibranch coalbed methane (CBM) well. The leaf vein structure of leaves was analyzed by leaf specimen scanning and microstructure measurements. Fluorescence labeling experiments were used to study the influence of leaf vein structure on moisture transport, and the geometric characteristics were obtained. A CBM extraction physical simulation experiment was carried out in a custom‐made experimental system. The temporal and spatial evolution of seepage‐temperature fields in reservoir during CBM recovery were studied, and the influence of leaf vein geometric characteristics and how they affected was analyzed. The results indicated that in experimental gas extraction, asymmetrically distributed branch wells improved the CBM recovery 4.02% higher than symmetric structure after 1000 seconds. The reduction in branch well angle leads to the decrease in gas pressure relief. If the branch well angle is reduced by 20°, it reduced by 11.34% after 4000 seconds. When the branch well length increased by 50%, it increased by 28.37%. Coalbed methane recovery effect can be improved by 6.81%, when the distance between branch wells increased by 50%. In the early extraction stage, the reduction in methane pressure and reservoir temperature was positively correlated with the initial methane pressure, but they were less affected in the later stage.
Effect-Directed Analysis of Progestogens and Glucocorticoids at Trace Concentrations in River Water
Authors: Hashmi Muhammad Arslan Kamal , Krauss Martin , Escher Beate I. , Teodorovic Ivana , Brack Werner
Published: October 2019

Effect-based monitoring is increasingly applied to detect and—in conjunction with chemical analysis—to identify endocrine-disrupting compounds (EDCs) in the environment. Although this approach of effect-directed analysis has been successfully demonstrated for estrogenicity and androgenicity, data on progestogens and glucocorticoids driving endocrine disruption are quite limited. We investigated progestogenic and glucocorticoid activities in Danube River water receiving untreated wastewater from Novi Sad, Serbia. After a 2-step fractionation, all fractions were tested with reporter gene bioassays for agonistic and antagonistic hormonal responses at progestogenic and glucocorticoid hormone receptors as well as with target and nontarget analytical screening of active fractions by liquid chromatography–high-resolution mass spectrometry. Due to masking by cytotoxic mixture components, the effects could not be detected in the raw water extract but were unraveled only after fractionation. Target chemical screening of the fraction that was active in the progesterone receptor (PR) assay revealed that progesterone and megestrol acetate were predominant drivers of PR-mediated activity along with medroxyprogesterone, dihydrotestosterone, androsterone, and epiandrosterone. Hydrocortisone was detected at sub-ng/L concentration in the active fraction in the glucocorticoid receptor (GR) assay but could not explain a significant fraction of the observed GR activity. The present study indicates that effect-based monitoring is a powerful tool to detect EDCs in the aquatic environment but that fractionation may be required to avoid masking effects of mixture components. Future effect-directed analysis studies are required to better understand the occurrence of EDCs and masking compounds in different lipophilicity windows, to finally reduce fractionation requirements for monitoring to a smart clean-up. Environ Toxicol Chem 2019;39:189–199. © 2019 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC.

Abstract

Summary of the work flow of effect-directed analysis of wastewater-impacted Danube River water and the results specifying the main drivers of progestogenic effects.
Integrating thermal‐concentration smoothed profile with lattice Boltzmann methods for simulating sedimentation of nonisothermal circular particles
Authors: Safa Raziyeh , Soltani Goharrizi Ataallah , Jahanshahi Javaran Ebrahim , Jafari Saeed
Published: October 2019

A thermal‐concentration smoothed profile‐lattice Boltzmann method is proposed to study the effect of the concentration field on the dynamic behavior of nonisothermal cylindrical particles during the sedimentation process. The velocity, temperature, and concentration equations are solved using the lattice Boltzmann method. Moreover, the smoothed profile method is employed to enforce the nonslip boundary condition as well as constant temperature and constant concentration boundary conditions at the particles surfaces. Moreover, the Boussinesq approximation is used to couple the velocities, temperatures, and concentrations fields. The proposed combined method is validated by comparing the present numerical results with those found in the literature, showing good consistency. Then, the effect of the concentration buoyancy on the behavior of nonisothermal particles is discussed. In addition, the effect of Prandtl, Schmidt, and thermal Grashof numbers on the settling process is investigated. The results show that, by adding the effect of concentration, the maximum settling velocity of hot particles is reduced more relative to the cold ones; accordingly, the cold particles are settled faster than the hot ones. Finally, the sedimentation of two particles in a container at high thermal Grashof is investigated. It is shown that, at high thermal Grashof, there is an intense competition between the buoyancy force and gravity for the hot particles. The buoyancy flow generated leads to the reversal of the drafting‐kissing‐tumbling motion of the hot particles, making the particles move upward.
Method of detection of thyroid nodules: correlation with frequency of fine‐needle aspiration and malignancy rate
Authors: Rothberger Gary D. , Cohen Melissa , Sahay Priya , Szczepanczyk Paula T. , Islam Shahidul
Published: October 2019

Background

Thyroid nodules are commonly found by screening, and the clinical implications are unclear.

Methods

We retrospectively studied 460 patients who were evaluated for thyroid nodules. Medical records were queried to determine how the nodules were detected. We compared the rates of fine needle aspiration (FNA) and malignancy between nodules detected clinically, incidentally on imaging, or by screening.

Results

Nodules were detected clinically in 184 patients (40%), incidentally in 121 patients (26%), and by screening in 155 patients (34%). The rates of FNA and malignancy were lower for patients with nodules detected by screening (28% and 1%, respectively), compared to patients with clinically apparent nodules (75% and 15%) and patients with incidental nodules (69% and 8% [P < .001]).

Conclusion

Thyroid nodules detected via screening has a lower rate of FNA and is less likely to be diagnosed as a malignancy compared to nodules detected clinically or incidentally on imaging. Thyroid ultrasound examinations should be reserved for nodules that are clinically apparent or to evaluate nodules found incidentally on imaging.
Overexpressed microRNA‐103a‐3p inhibits acute lower‐extremity deep venous thrombosis via inhibition of CXCL12
Authors: Sun Shaoliang , Chai Shanyi , Zhang Feng , Lu Lu
Published: October 2019

Studies have shown that microRNAs (miRNAs) participate in almost all pathological and physiological processes including acute lower‐extremity deep venous thrombosis (LEDVT). Here, this study was designed to elucidate the possible function of miR‐103a‐3p in acute LEDVT. Expression of miR‐103a‐3p and chemokine C‐X‐C motif ligand 12 (CXCL12) was initially quantified in plasma collected from 81 LEDVT patients. Then LEDVT mouse models were established by injection with 3% sodium pentobarbital. The interaction between miR‐103a‐3p and CXCL12 was identified by dual‐luciferase reporter gene assay. After gain‐ and loss‐of‐function studies, interleukin‐6 (IL‐6) and IL‐8 and tissue factor (TF) levels, and expression of plasminogen activator inhibitors (PAIs), von Willebrand factor (vWF), thromboxane A2 (TH‐A2), F4/80, IL‐12, Arginase‐1 (Arg‐1) and CD206 were determined using enzyme‐linked immunosorbent assay (ELISA), reverse transcription quantitative polymerase chain reaction (RT‐qPCR) and western blot analysis, respectively. miR‐103a‐3p was downregulated, while CXCL12 was upregulated in patients and mice with LEDVT. miR‐103a‐3p targets CXCL12 and inhibited its expression. Overexpressed miR‐103a‐3p or downregulated CXCL12 decreased expression of IL‐6, IL‐8, TF, PAIs, vWF, TH‐A2, M1 markers (IL‐6 and IL‐12), yet increased expression of M2 markers (Arg‐1 and CD206) in LEDVT mice. Additionally, upregulated miR‐103a‐3p or silencing CXCL12 suppressed thrombosis in LEDVT mice. However, overexpression of CXCL12 reversed the tendency mentioned above. Altogether, miR‐103a‐3p can potentially downregulate CXCL12 expression to disrupt inflammatory response and thrombosis, ultimately preventing the development of LEDVT. Our findings underscore a possible alternative therapeutic strategy to limit LEDVT.
Resolvin D1 reduces mitochondrial damage to photoreceptors of primary retinal cells exposed to high glucose
Authors: Trotta Maria Consiglia , Pieretti Gorizio , Petrillo Francesco , Alessio Nicola , Hermenean Anca , Maisto Rosa , D'Amico Michele
Published: October 2019

No study has investigated the interaction of Resolvin D1 (RvD1) with mitochondrial damage of retinal cells caused by diabetes. This study aims to investigate the effects of RvD1 (50 nM) on morphological and biochemical indicators of mitochondrial damage in primary retinal cells exposed to 30 mM d‐glucose high glucose (HG). HG‐cells exhibited photoreceptor damage characterized by short and small mitochondria with prevalent mitochondrial disruption, fragmentation, and aggregation. The cells had low mitochondrial transporters TIMM44 and TOMM40, Connexin 43, NAD/NADH ratio, and ATP levels, whereas increased cytosolic cytochrome c. Moreover, they expressed high cytosolic metalloproteinase matrix metallopeptidase 9 (MMP‐9) and MMP‐2 activity. HG‐cells treated with RvD1 (50 nM) showed reduced reactive oxygen species levels, improved mitochondrial morphology and function, promoted mitochondrial DNA repair by OGG1, and reduced cell apoptosis and metalloproteinase activity. Therefore, RvD1 induces protection from high glucose‐load to the retinal cell and promotes their survival by decreasing cytosolic MMP and mitochondrial damage.