bluuebunny/crossref_metadata_2025_split huggingface dataset:
Novel method enabling a rapid vitality determination of cyanobacteria
Authors: Witthohn Marco , Schwarz Anna , Walther Jakob , Strieth Dorina , Ulber Roland , Muffler Kai 
Published: October 2020

AbstractCyanobacteria represent a large group of bacteria with underestimated scientific potential. Recent studies indicate them as a great reservoir of secondary metabolites with antifungal, antiviral or antibacterial activity. However, common, well established research techniques cannot be easily adapted to these organisms. Slow growth rates and irregular cell aggregates constitute challenges for researchers dealing with cyanobacteria. In this work, we present an innovative new method enabling a quick, easy and economical vitality determination of cyanobacterial strains, as, e.g. required for the finding of optimal cryopreservation conditions. We were able to measure the vitality of previously cryopreserved and defrosted Trichocoleus sociatus samples within 45 min by means of their O2‐production. For each run, a cell wet mass of only 0.5 g was required. By application of this method, we could find DMSO (5% v/v) and glycerin (15% v/v) to be the most promising cryoprotectants for the conservation of T. sociatus cells. DMSO and glycerin guaranteed a vitality rate of 80–90% and 60–70% after up to four weeks of cryopreservation, compared to fresh cell material.
Material choices for triboelectric nanogenerators: A critical review
Authors: Zhang Renyun , Olin Håkan 
Published: October 2020

AbstractA triboelectric nanogenerator (TENG) is a novel technology with applications in many areas, including energy harvesting, self‐powered sensing, medication, and electronics. The materials used as triboelectric layers are diverse and include polymers, metals, and inorganic materials. The most commonly used materials are dielectric polymers such as PTFE, FEP, PDMS, and Kapton. Green materials, such as cellulose‐based materials, have recently gained increasing interest, and the performance of TENGs using cellulose materials has improved. The material choices are of great importance for TENGs since the triboelectric effects of the materials are fundamental for TENGs. To design a TENG for a particular application, several parameters need to be considered, such as power density, stability, flexibility, and sustainability. This critical review will summarize and evaluate the material choices for TENGs in different applications.image
Simplified Dynamic Model for Post‐tensioned Cross‐laminated Timber Rocking Walls
Authors: Pei S. , Huang D. , Berman J. W. , Wichman S. K. 
Published: October 2020

AbstractThis paper presents a computationally efficient numerical model for predicting seismic responses of post‐tensioned cross‐laminated timber (CLT) rocking wall systems. The rocking wall is modeled as a simple linear beam element with a nonlinear rotational spring at the base. The model is primarily intended for preliminary design and assessment of multistory buildings using this particular lateral system. A method was developed to determine the nonlinear rotational spring parameters by considering the dimension of the CLT wall panel and post‐tensioned steel rods and energy dissipating devices’ contributions. The proposed model was validated by comparing the simulated results with the responses from a series of shake table tests of a full‐scale two‐story building with CLT rocking walls. The numerical results show reasonable agreement with the shake table test results considering the simplicity of the model.
New insight on the open‐circuit voltage of perovskite solar cells: The role of defect‐density distribution and electric field in the active layer
Authors: Zarabinia Nazila , Rasuli Reza , Mohajerani Ezeddin 
Published: October 2020

SummaryIn this article, we study the J–V characteristic of a perovskite solar cell (PSC) prepared by the two‐step method. PSCs were fabricated by methylammonium lead iodide using the sequential deposition method. We describe J–V curves using a modified dynamic electrical model based on an asymmetric electric field. In addition, we simulated the PSCs by solar cell capacitance simulator package to investigate the role of trap‐density distribution in cell performance. The experimentally optimized device shows an enhancement in the open‐circuit voltage (VOC) from 1.08 to 1.21 V. Simulation results show that the increase in VOC up to 1.15 V is corresponding to a trap‐density of 2.38×1015 cm−3. However, these results predict that a decrease in the trap‐density can increases the VOC and FF up to 1.19 V and 79% while the modified dynamic electrical model gives the J–V characteristic as well as experimental results. Our results suggest that the increase in VOC can be attributed to the asymmetric electric field at the interface of the perovskite layer.
Enhanced electrochemical performance of lanthanum ferrite decorated reduced graphene oxide nanocomposite electrodes prepared by in situ microwave irradiation for energy storage applications
Authors: Sivakumar Natarajan , Nagaraju Perumal , Alsalme Ali , Alghamdi Abdulaziz , Jayavel Ramasamy 
Published: October 2020

SummaryLanthanum ferrite decorated reduced graphene oxide (LaFeO3/rGO) nanocomposite is prepared by in‐situ microwave irradiation method. The X‐ray diffraction study reveals the single phase orthorhombic structure of LaFeO3 nanoparticles and LaFeO3/rGO nanocomposites. The FTIR study reveals various vibrational modes and the characteristic D and G bands of the Raman spectrum confirms the formation of reduced graphene oxide. The SEM and HR‐TEM images demonstrate that spherical LaFeO3 particles are decorated on 2D graphene sheets. From the HR‐TEM study, the average particle size of LaFeO3 is estimated to be 23 nm. The synergistic effect of 3D LaFeO3 nanoparticles and 2D graphene layers offers more active sites to achieve the enhanced electrochemical performance. The specific capacitance of LaFeO3/rGO composites is measured to be 170 Fg−1 at 10 mV s−1. The composite electrode has admirable cyclic stability, better Columbic efficiency and improved capacitance retention with great potential for supercapacitor applications.
Assessment of migration regularity of phthalates from food packaging materials
Authors: Liu Jing‐Min , Li Chun‐Yang , Yang Fei‐er , Zhao Ning , Lv Shi‐Wen , Liu Ji‐Chao , Chen Li‐Jun , He Ze , Zhang Yan , Wang Shuo 
Published: October 2020

AbstractPhthalate acid esters (PAEs) are one of the essential plastic additives which may lead to plenty of harmful effects, including reproductive toxicity, teratogenicity, and carcinogenicity. Increasing attention has been paid to the migration of plasticizer. In this article, the disposable plastic lunch boxes were taken as the research object. The result showed that dibutyl phthalate (DBP) and diisobutyl phthalate (DIBP) have been mainly found, whose content was 1.5 mg/kg and 2.4 mg/kg, respectively. The LOD was 2 ng/g, and LOQ was 6.7 ng/g. We further investigated the migration of PAEs into the simulated liquid at different temperature conditions. Then, the linear fitting performing by first‐order kinetic migration model revealed that the lower the polarity of the simulated liquid, the larger the rate constant K1 and initial release rate V0. The higher the temperature, the bigger the K1 and V0.
Can sentiments on macroeconomic news explain stock returns? Evidence form social network data
Authors: Xu Yingying , Zhao Jichang 
Published: October 2020

AbstractMacroeconomic factors and sentiments affect investors' decisions and thus stock returns. However, do sentiments on macro‐economic news explain stock returns? This article proposes a theoretical model to explain the relationship between stock returns and the market misperception which is driven by investors' sentiments. Then, microblogs regarding the macro‐economy posted on Sina Weibo, a mainstream Chinese Social Network Site, are extracted to measure investors' macroeconomic sentiments (IMSs) through machine learning approaches. A preliminary event study suggests that IMSs capture the development of influential macroeconomic events. Empirical results demonstrate that orthogonalized IMSs including anger, disgust, fear, joy and sadness exert heterogeneously significant effects on the Shanghai Composite Index (SHCI), and no reverse effect is found. Thus, the IMS contains additional information related to the macro‐economy; but cannot be explained by macroeconomic factors. IMSs improve the in‐ and out‐of‐sample predictabilities of SHCI returns. Thereby, investors' sentiment can be an important channel through which the macro‐economy affects the stock market.
Exosomes derived from T regulatory cells relieve inflammatory bowel disease by transferring miR‐195a‐3p
Authors: Liao Fei , Lu Xiaohong , Dong Weiguo 
Published: October 2020

AbstractPrevious studies have demonstrated the therapeutic effects of regulatory T (Treg) cells on inflammatory bowel disease (IBD), but the mechanism is not well‐understood. Exosomes have been proposed as a novel mechanism underlying the action of Tregs. This study aimed to investigate the therapeutic effects of exosomes secreted by Treg cells (Treg‐Exo) on IBD and to explore the underlying mechanism. Treg‐Exo was isolated from BALB/c mouse spleen mononuclear cells and then injected into a murine model of IBD induced by dextran sodium sulfate (DSS) exposure. A co‐culture model of Treg‐Exo and colonic epithelial YAMC cells in the presence of TNF‐α was used to investigate the communication between Tregs and intestinal epithelial cells. in vitro results showed that Treg‐Exo could be transferred to YAMC cells where Treg‐Exo promoted cell proliferation and inhibited cell apoptosis. Animal experiments showed that Treg‐Exo administration alleviated the DSS‐induced IBD in mice. The therapeutic effects of Treg‐Exo both in vitro and in vivo were eliminated when miR‐195a‐3p expression was inhibited in Treg‐Exo. The pro‐apoptotic Caspase 12 was identified as a direct target of miR‐195a‐3p. In conclusion, Treg‐Exo alleviated the DSS‐induced IBD through transferring miR‐195a‐3p.
Effects of the MTOR and AKT1 genes polymorphisms on papillary thyroid cancer development
Authors: Maruei‐Milan Rostam , Saravani Mohsen , Heidari Zahra , Asadi‐Tarani Mina , Salimi Saeedeh 
Published: October 2020

AbstractPapillary thyroid cancer (PTC) is the most common form of thyroid cancer, comprising 80% of all thyroid malignancies. The phosphoinositide‐3‐kinase–protein kinase B/Akt (PI3K‐PKB/Akt) pathway is a main pathway in control of cell growth. Activated mTOR and Akt are involved in the development and progression of the PTC. This study aimed to evaluate the effects of MTOR (rs2536 and rs2295080) and AKT1 (rs2494732, rs1130214, and rs1130233) polymorphisms on PTC susceptibility. This study was conducted on 131 PTC patients and 144 healthy subjects. Genotype analysis was done using polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP) methods. Our results showed no statistically significant association between MTOR rs2536, AKT1 rs2494732, and rs1130214 polymorphisms and PTC development. However, MTOR rs2295080 polymorphism was found to be associated with a decreased risk of PTC in dominant and allelic models. The TT genotype of AKT1 rs1130233 was significantly higher in the PTC group in comparison to the controls, with a 3.5‐fold increased risk for developing PTC. Furthermore, the allelic distribution also showed the T allele of rs1130233 as a risk factor for PTC occurrence. In conclusion, our results suggest the MTOR rs2295080 and AkT1 rs1130233 as the protective and risk factors for PTC development, respectively.
BALB/c female subjected to valproic acid during gestational period exhibited greater microglial and behavioral changes than male mice: A significant contra intuitive result
Authors: dos Santos Alinne Lorrany Gomes , de Leão Ellen Rose Leandro Ponce , de Almeida Miranda Diego , de Souza Dilza Nazaré Colares , Picanço Diniz Cristovam Wanderley , Diniz Daniel Guerreiro 
Published: October 2020

AbstractMost animal model studies of autism spectrum disorders (ASD) were performed in males. Thus, little is known about the mechanisms underlying disease progression in females. Here, we searched for potential influences of sex and environment on gestational valproic acid‐induced behavioral abnormalities using hippocampal‐dependent tasks, and on number and morphometry of microglia of the molecular layer of the dentate gyrus (Mol‐DG). We compared male and females BALB/c control mice with BALB/c mice gestationally exposed to VPA with regards to exploratory activity and risk assessment in novel environments. Pregnant females and males on gestational day 12.5 received VPA in saline (600 mg/kg body weight) or an equal volume of saline by gavage. After weaning, female and male offspring were housed separately either in standard laboratory cages (SE) or enriched cages (EE). At 5 months of age, these mice underwent behavioral testing and had their brains processed for microglia IBA1 immunolabeling. Compared with control mice, VPA‐exposed mice exhibited abnormal behavior in exploring novel environments and assessing risk, and these effects were significantly greater in females than in males and less intense among mice from enriched cages. Three‐way ANOVA revealed that environment, sex and valproic acid conditions interacted and altered the behavior results. Microglia number and volume of the Mol‐DG were significantly higher in VPA‐exposed groups raised in standard cages. The results of counting the intersects of microglia branching on Sholl's circles analyzed with permutational MANOVA, demonstrated that in comparison with males, there was a greater reduction in the number of intersections in females raised in standard cages. These findings suggest that the increased microglia and morphological changes might be associated with behavioral dysfunction in ASD. Moreover, the somatomotor and cognitive stimulation of environmental enrichment started at weaning may be beneficial for reducing behavioral abnormalities and reduction of microglia response in adulthood.
Atmospheric deposition of arsenic, cadmium, copper, lead, and zinc near an operating and an abandoned lead smelter
Authors: Xing Weiqin , Yang Hao , Ippolito James A. , Zhao Qiang , Zhang Yuqing , Scheckel Kirk G. , Li Liping 
Published: October 2020

AbstractAtmospheric deposition samples were collected over 15 mo at several locations near an operating smelter and an abandoned Pb smelter to investigate the contribution of Pb smelting to depositional fluxes and potential local air quality degradation. Samples were analyzed for As, Cd, Cu, Pb, and Zn and subjected to scanning electron microscopy (SEM)–energy dispersive spectroscopy (EDS). Concentrations of Cd and Pb at both sites were greater than at the control site (p < .05), and significant correlations existed between Cd and Pb concentrations at both sites (p < .05). Monthly depositional flux variations at both sites were similar, with greater deposition during cold and dry periods. Heavy metal(loid)s deposition during these periods was correlated with wind speed. Greater Cd depositional flux differences were found between the smelter and control sites compared with other elements. The SEM images suggested that some particles at the operating smelter site were from Pb smelting material. However, most particles at both sites had no characteristics of smelting, suggesting reactions occurred between the smelter‐emitted particles and soil components. The EDS results indicated that atmospheric deposition from both sites had lower Pb concentrations than smelting material or ash. The main atmospheric deposition source at the operating and abandoned sites was likely from the resuspension of heavy metal(loid)‐enriched soil particles. Greater risk of air pollution from historical Pb smelting facilities exists years after closing down. Reducing soil wind erosional losses may help reduce heavy metal(loid)s dispersion across environments.
Fungemia in COVID‐19 ICU patients, a single medical center experience
Authors: Bishburg Eliahu , Okoh Alexis , Nagarakanti Sandhya R. , Lindner Marc , Migliore Christina , Patel Pratik 
Published: October 2020

AbstractA known proportion of patients who are admitted for the novel coronavirus disease 2019 (COVID‐19) requires intensive care unit (ICU) level of care. Prolonged ICU stay is a risk factor for the development of nosocomial candidemia. The current study aimed to investigate the incidence and risk factors associated with the development of nosocomial candidemia among patients admitted to the ICU for COVID‐19. Patients who developed nosocomial candidemia were identified, and their clinical course was reported. A 1:3 case control matching was used to identify non‐candidemia patients who served as controls. 89 patients were admitted to the ICU for COVID‐19 during the study period. The incidence of nosocomial candidemia was 8.9% (n = 8). Case‐control matching identified 24 patients with similar disease severity at the time of ICU admission. Median time to first isolation of yeast was 26 days. Candidemia patients reported longer median ICU stay than controls. (40 vs. 10 days, p = .004). In hospital death rates were comparable in both groups (38% vs. 54%, p = .548). Prolonged mechanical ventilation support was associated with the development of nosocomial candidemia.
Metallothionein levels in gingival crevicular fluid, saliva, and serum of smokers and non‐smokers with chronic periodontitis
Authors: Yadav Vikender S. , Mir Riyaz A. , Bhatia Anu , Yadav Rakhee , Shadang Mahaiwon , Chauhan Shyam S. , Dhingra Kunaal , Kharbanda Om P. , Yadav Renu , Garg Rahul 
Published: October 2020

AbstractBackgroundMetallothionein (MT), a cysteine rich protein is involved as a radical scavenger in several pathological conditions associated with oxidative stress; however, its role in periodontal disease still remains elusive. The aim of this cross‐sectional study is to determine the serum, saliva and gingival crevicular fluid (GCF) levels of MT in smokers (S) and non‐smokers (NS) with chronic periodontitis (CP), and compare them with those of periodontally healthy (PH) individuals.MethodsA total of 85 participants were enrolled: 45 patients with CP (23 S [CP+S] and 22 NS [CP+NS]) and 40 PH individuals (20 S [PH+S] and 20 NS [PH+NS]). In all the study participants, clinical periodontal parameters (plaque index, gingival index, sulcus bleeding index, probing depth, and clinical attachment level) were recorded and samples of serum, saliva and GCF were collected. Enzyme‐linked immunosorbent assay was used to determine the levels of MT in the samples.ResultsAll periodontal clinical parameters were significantly higher in the CP groups as compared to PH groups (P < 0.05). MT levels in CP+S group were significantly raised in comparison to other three groups. There was no statistically significant difference in MT levels among CP+NS and PH+S groups (P > 0.05); however, relatively higher levels were observed in GCF and saliva in CP+NS group. When all the study groups were observed together, MT levels were positively correlated with clinical parameters.ConclusionsResults of present study suggest that smoking and CP can induce the synthesis of MT owing to increased oxidative stress and heavy metals intoxication. Further longitudinal studies with large sample size and an interventional arm are needed to substantiate the role of MT as a potential biomarker in periodontitis.
Impact of mucosal phenotype on marginal bone levels around tissue level implants: A prospective controlled trial
Authors: Garaicoa‐Pazmino Carlos , Mendonça Gustavo , Ou Alice , Chan Hsun‐Liang , Mailoa James , Suárez‐López Del Amo Fernando , Wang Hom‐Lay 
Published: October 2020

AbstractBackgroundThe aim of this 1‐year prospective clinical trial was to compare clinical parameters and marginal bone levels (MBLs) around tissue level implants with a partially smooth collar between patients with thin (≤2 mm) and thick (>2 mm) vertical mucosal phenotypes.MethodsThirty patients needing a single dental implant were recruited and allocated to thin (n = 14) or thick (n = 16) phenotype groups. Post‐restoration, clinical (probing depth, recession, width of keratinized mucosa, bleeding on probing, suppuration, implant mobility, plaque index, and gingival index) and radiographic bone level measurements were recorded at different timepoints for 1 year.ResultsTwenty‐six patients (13 per group) completed the 1‐year examination. No implants were lost (100% survival rate). There were no significant differences (P >0.05) between thin and thick vertical mucosal phenotypes for any clinical parameter or for the radiographic MBL.ConclusionsTissue level implants at 1 year of function placed in thin vertical mucosa achieved similar clinical parameters and radiographic MBLs as those in thick tissue. The formation of the peri‐implant supracrestal tissue height plays a key role in MBL than mucosal thickness in tissue level implant.
The impact of ultraviolet laser excitation during Raman spectroscopy of hexagonal boron nitride thin films
Authors: Karim Marwa , J. Lopes Joao Marcelo , Ramsteiner Manfred 
Published: October 2020

AbstractWe utilized excitation in the ultraviolet (UV) spectral range for the study of hexagonal boron nitride (h‐BN) thin films on different substrates by Raman spectroscopy. Whereas UV excitation offers fundamental advantages for the investigation of h‐BN and heterostructures with graphene, the actual Raman spectra recorded under ambient conditions reveal a temporal decay of the signal intensity. The disappearance of the Raman signal is found to be induced by thermally activated chemical reactions with ambient molecules at the h‐BN surface. The chemical reactions could be strongly suppressed under vacuum conditions which, however, favor the formation of a carbonaceous surface contamination layer. For the improvement of the signal‐to‐noise ratio under ambient conditions, we propose a line‐scan method for the acquisition of UV Raman spectra in atomically thin h‐BN, a material which is expected to play a key role in future technologies based on 2D van der Waals heterostructures.
Rate coefficients for the reactions of OH with butanols from 298 K to temperatures relevant for low‐temperature combustion
Authors: Sime Samantha L. , Blitz Mark A. , Seakins Paul W. 
Published: October 2020

AbstractRate coefficients for the reactions of OH with n, s, and iso‐butanol have been measured over the temperature range 298 to ∼650 K. The rate coefficients display significant curvature over this temperature range and bridge the gap between previous low‐temperature measurements with a negative temperature dependence and higher temperature shock tube measurements that have a positive temperature dependence. In combination with literature data, the following parameterizations are recommended:k1,OH + n‐butanol(T) = (3.8 ± 10.4) × 10−19T2.48 ± 0.37exp ((840 ± 161)/T) cm3 molecule−1 s−1k2,OH + s‐butanol(T) = (3.5 ± 3.0) × 10−20T2.76 ± 0.12exp ((1085 ± 55)/T) cm3 molecule−1 s−1k3,OH + i‐butanol(T) = (5.1 ± 5.3) × 10−20T2.72 ± 0.14exp ((1059 ± 66)/T) cm3 molecule−1 s−1k4,OH + t‐butanol(T) = (8.8 ± 10.4) × 10−22T3.24 ± 0.15exp ((711 ± 83)/T) cm3 molecule−1 s−1Comparison of the current data with the higher shock tube measurements suggests that at temperatures of ∼1000 K, the OH yields, primarily from decomposition of β‐hydroxyperoxy radicals, are ∼0.3 (n‐butanol), ∼0.3 (s‐butanol) and ∼0.2 (iso‐butanol) with β‐hydroxyperoxy decompositions generating OH, and a butene as the main products. The data suggest that decomposition of β‐hydroxyperoxy radicals predominantly occurs via OH elimination.