bluuebunny/crossref_metadata_2025_split huggingface dataset:
University Teachers’ Perception of Quality in Higher Education in Ethiopia: A Case Study of Dire Dawa University
Authors: Woldeamanuel Melaku Masresha , Goshu Belay Sitotaw 
Published: August 2019

This article empirically assesses perception of quality in higher education in Ethiopia. The data was collected from one higher educational institution where the staffs are graduates of 31 different universities in Ethiopia. The information used in this study was obtained through administration of questionnaires. The main participants are the academic staff of the University. The total number of staff that participated in the research was 365. Purposive sampling technique was employed to select 365 teachers (302 male and 63 female) and seventeen classrooms were observed and twelve group discussions carried out with participants of Ethiopian educational roadmap. Data were analyzed by both descriptive statistics of percentages and inferential statistics of, t-test, correlation and one way ANOVA. Results indicated that teacher’ valued input indicators of quality of education more than process and output indicators. Output indicators received the lowest rating. Teachers’ practice also indicated that they apply process indicators in a reasonable manner. The results of relationship between practices of teaching learning processes revealed that, as teachers’ perception toward quality teaching learning process increases their practice of elements of constructivism also increases.
Kinetics of Enhancement for Corneal Cross-linking: Proposed Model for a Two-initiator System
Authors: Lin Jui-Teng 
Published: August 2019

Aims: To derive kinetic equations and analytic formulas for efficacy enhancement of corneal collagen crosslinking (CXL) in a 2-initiator system.
Study Design: Modeling the kinetics of CXL.
Place and Duration of Study: Taipei, Taiwan, between between January 2019 to June, 2019.
Methodology: Coupled rate equations are derived for two initiators system for a type-II process, consisting of a primary initiator (PA), and a co-initiator (PB) as an enhancer, having 3 cross linking pathways: Two radical-mediated (or electron transfer) pathways, and one oxygen-mediated (or energy transfer) pathway. For a type-II process, the triplet state T* interacts with the co-initiator, PB, to form the primary radicals R’, and an active intermediates radical, R, which could interact with the substrate [M] for crosslink, or be inhibited by oxygen [O2], or bimolecular termination. Rate equations, based on lifetime of triplet-state and oxygen singlet-state, are used to analyze the measured results in a rose-Bengal system with an enhanced initiator.
Results: Additive enhancer-monomer of arginine added to a rose Bengal photosensitizer may enhance the production of free radicals under a green-light CXL. D2O may extends the lifetime of oxygen singlet state and thus improve the efficacy. Our formulas predicted features are consistent with the measured results.
Conclusion: Efficacy may be improved by enhancer-monomer or extended lifetime of photosensitizer triplet-state or oxygen singlet state.
Seasonal Autoregressive Integrated Moving Average (SARIMA) Model for the Analysis of Frequency of Monthly Rainfall in Osun State, Nigeria
Authors: Adams Samuel Olorunfemi , Mustapha Bello , Alumbugu Auta Irinew 
Published: August 2019

The Seasonal Autoregressive Integrated Moving Average (SARIMA) model is proposed for Osun State monthly rainfall data and the analysis was based on probability time series modeling approach. The Plot of the original data shows that the time series is stationary and the Augmented Dickey-Fuller test did not suggest otherwise. The graph further displays evidence of seasonality and it was removed by seasonal differencing. The plots of the ACF and PACF show spikes at seasonal lags respectively, suggesting SARIMA (1, 0, 1) (2, 1, 1). Though the diagnostic check on the model favoured the fitted model, the Auto Regressive parameter was found to be statistically insignificant and this led to a reduced SARIMA (1, 0, 1) (1, 1, 1) model that best fit the data and was used to make forecast.
MicroRNA‐9 exerts antitumor effects on hepatocellular carcinoma progression by targeting HMGA2
Authors: Xu Xiangang , Zou Haibo , Luo Lanyun , Wang Xiankui , Wang Guan 
Published: August 2019

Accumulating evidence has demonstrated that the aberrant expression of microRNAs (miRs or miRNAs) may contribute to the initiation and progression of various types of human cancer and may also constitute biomarkers for cancer diagnosis and therapy. However, the specific function of miR‐9 in hepatocellular carcinoma (HCC) remains unclear, and the mechanisms that underlie HCC are incompletely understood. Here, we report that miR‐9 expression was significantly decreased in clinical tumor tissue samples, as well as in a cohort of HCC cell lines. In addition, it was demonstrated that overexpression of miR‐9 suppressed the proliferative and migratory capacity of HCC cells and impaired cell cycle progression. Furthermore, high mobility group AT‐hook 2 (HMGA2) was verified as a downstream target gene of miR‐9 using a luciferase reporter assay. Quantitative RT‐PCR and western blotting implicated HMGA2 in the miR‐9‐mediated reduction of HCC cell growth. In vivo, transfection with miR‐9 mimics down‐regulated the expression of HMGA2, thus leading to a dramatic reduction in tumor growth in a mouse xenograft model. These results suggest that miR‐9 may exert critical antitumor effects on HCC by directly targeting HMGA2, and the miR9/HMGA2 signaling pathway may be of use for the diagnosis and prognosis of patients with HCC.
Impact of organ motion on volumetric and dosimetric parameters in stomach lymphomas treated with intensity‐modulated radiotherapy
Authors: Uchinami Yusuke , Suzuki Ryusuke , Katoh Norio , Taguchi Hiroshi , Yasuda Koichi , Miyamoto Naoki , Ito Yoichi M. , Shimizu Shinichi , Shirato Hiroki 
Published: August 2019

AbstractPurposeInterplay effects may influence dose distributions to a moving target when using dynamic delivery techniques such as intensity‐modulated radiotherapy (IMRT). The aim of this study was to evaluate the impact of organ motion on volumetric and dosimetric parameters in stomach lymphomas treated with IMRT.MethodsTen patients who had been treated with IMRT for stomach lymphomas were enrolled. The clinical target volume (CTV) was contoured as the whole stomach. Considering interfractional uncertainty, the internal target volume (ITV) margin was uniformly 1.5 cm to the CTV and then modified based on the 4DCT images in case of the large respiratory motion. The planning target volume (PTV) was created by adding 5 mm to the ITV. The impact of organ motion on the volumetric and dosimetric parameters was evaluated retrospectively (4D simulation). The organ motion was reproduced by shifting the isocenter on the radiation treatment planning system. Several simulation plans were created to test the influence of the beam‐on timing in the respiration cycle on the dose distribution. The homogeneity index (HI), volume percentage of stomach covered by the prescribed dose (Vp), and D99 of the CTV were evaluated.ResultsThe organ motion was the largest in the superior‐inferior direction (10.1 ± 4.5 mm [average ± SD]). Stomach volume in each respiratory phase compared to the mean volume varied approximately within a ± 5% range in most of the patients. The PTV margin was sufficiently large to cover the CTV during the IMRT. There was a significant reduction in Vp and D99 but not in HI in the 4D simulation in free‐breathing and multiple fractions compared to the clinically‐used plan (P < 0.05) suggesting that interplay effects deteriorate the dose distribution. The absolute difference of D99 was less than 1% of the prescribed dose.ConclusionsThere were significant interplay effects affecting the dose distribution in stomach IMRT. The magnitude of the dose reduction was small when patients were treated on free‐breathing and multiple fractions.
Blood transcriptomic biomarker as a surrogate of ischemic brain gene expression
Authors: Ramsay LeeAnn , Quillé Marie‐Lise , Orset Cyrille , de la Grange Pierre , Rousselet Estelle , Férec Claude , Le Gac Gérald , Génin Emmanuelle , Timsit Serge 
Published: August 2019

AbstractObjectivesBlood biomarkers for cerebral tissue ischemia are lacking. The goal was to identify a blood transcriptomic signature jointly identified in the ischemic brain.MethodsA nonhuman primate model with middle cerebral artery (MCA) territory infarction was used to study gene expression by microarray during acute ischemic cerebral stroke in the brain and the blood. Brain samples were collected in the infarcted and contralateral non‐infarcted cortex as well as blood samples before and after occlusion. Gene expression was compared between the two brain locations to find differentially expressed genes. The expressions of these genes were then compared in the blood pre‐ and post‐occlusion.ResultsHierarchical clustering of brain expression data revealed strong independent clustering of ischemic and nonischemic brain samples. The top five enriched, up‐regulated gene sets in the brain were TNF α signaling, apoptosis, P53 pathway, hypoxia, and UV response up. A comparison of differentially expressed genes in the brain and blood revealed a significant overlap of gene expression patterns. Stringent analysis of blood expression data from pre‐ and post‐occlusion samples in each monkey identified nine genes highly differentially expressed in both the brain and the blood. Many of these up‐regulated genes belong to pathways involved in cell death and DNA damage repair.InterpretationCommon gene expression profile can be identified in the brain and blood and clearly differentiates ischemic from nonischemic conditions. Therefore, specific blood transcriptomic signature may represent a surrogate for brain ischemic gene expression.
Model Placental Barrier Phenotypic Response to Fluoxetine and Sertraline: A Comparative Study
Authors: Arumugasaamy Navein , Gudelsky Alana , Hurley‐Novatny Amelia , Kim Peter C. W. , Fisher John P. 
Published: August 2019

AbstractMedications taken during pregnancy may significantly impact fetal development, yet there are few studies that rigorously assess medication safety due to ethical concerns. Selective serotonin reuptake inhibitors (SSRIs) are a class of drug increasingly being prescribed for depression, yet multiple studies have shown that taking SSRIs during pregnancy can lead to preterm birth and potential health concerns for the baby. Therefore, a biomimetic placental barrier model is utilized herein to assess transport profiles and phenotypic effects resulting from SSRI exposure, comparing fluoxetine and sertraline. Results show that the placental barrier quickly uptakes drug from the maternal side, but slowly releases on the fetal side. Phenotypically, there is a dose‐dependent change in cell adhesion molecule (CAM) and transforming growth factor beta (TGFβ) secretions, markers of cell adhesion and angiogenesis. Both drugs impact CAM secretions, whereas sertraline alone impacts TGFβ secretions. When evaluating cell type, it becomes clear that endothelial cells, not trophoblast, are the main cell type involved in these phenotypic changes. Overall, these findings further the understanding of SSRI transplacental transport and drug‐induced effects on the placental barrier.
Multifunctional Nanocomposites with High Strength and Capacitance Using 2D MXene and 1D Nanocellulose
Authors: Tian Weiqian , VahidMohammadi Armin , Reid Michael S. , Wang Zhen , Ouyang Liangqi , Erlandsson Johan , Pettersson Torbjörn , Wågberg Lars , Beidaghi Majid , Hamedi Mahiar M. 
Published: August 2019

AbstractThe family of two‐dimensional (2D) metal carbides and nitrides, known as MXenes, are among the most promising electrode materials for supercapacitors thanks to their high metal‐like electrical conductivity and surface‐functional‐group‐enabled pseudocapacitance. A major drawback of these materials is, however, the low mechanical strength, which prevents their applications in lightweight, flexible electronics. A strategy of assembling freestanding and mechanically robust MXene (Ti3C2Tx
) nanocomposites with one‐dimensional (1D) cellulose nanofibrils (CNFs) from their stable colloidal dispersions is reported. The high aspect ratio of CNF (width of ≈3.5 nm and length reaching tens of micrometers) and their special interactions with MXene enable nanocomposites with high mechanical strength without sacrificing electrochemical performance. CNF loading up to 20%, for example, shows a remarkably high mechanical strength of 341 MPa (an order of magnitude higher than pristine MXene films of 29 MPa) while still maintaining a high capacitance of 298 F g−1 and a high conductivity of 295 S cm−1. It is also demonstrated that MXene/CNF hybrid dispersions can be used as inks to print flexible micro‐supercapacitors with precise dimensions. This work paves the way for fabrication of robust multifunctional MXene nanocomposites for printed and lightweight structural devices.
Realizing Room‐Temperature Resonant Tunnel Magnetoresistance in Cr/Fe/MgAl2O4 Quasi‐Quantum Well Structures
Authors: Xiang Qingyi , Sukegawa Hiroaki , Belmoubarik Mohamed , Al‐Mahdawi Muftah , Scheike Thomas , Kasai Shinya , Miura Yoshio , Mitani Seiji 
Published: August 2019

AbstractThe quantum well (QW) realizes new functionalities due to the discrete electronic energy levels formed in the well‐shaped potential. Magnetic tunnel junctions (MTJs) combined with a quasi‐QW structure of Cr/ultrathin‐Fe/MgAl2O4(001)/Fe, in which the Cr quasi‐barrier layer confines Δ1 up‐spin electrons to the Fe well, are prepared with perfectly lattice‐matched interfaces and atomic layer number control. Resonant peaks are clearly observed in the differential conductance of the MTJs due to the formation of QWs. Furthermore, enhanced tunnel magnetoresistance (TMR) peaks at the resonant bias voltages are realized for the MTJs at room temperature, i.e., it is observed that TMR ratios at specific and even high bias‐voltages (Vbias) are larger than zero‐bias TMR ratios for the MTJs with odd Fe atomic layers, in contrast to the earlier experimental studies. In addition, a new finding in this study is unique sign changes in the temperature coefficient of resistance (TCR) depending on the Fe thickness and Vbias, which is interpreted as a signature of the QW formation of Δ1 symmetry electronic states. The present study suggests that the spin‐dependent resonant tunneling via the QWs formed in Cr/ultrathin‐Fe/MgAl2O4/Fe structures should open a new pathway to achieve a large TMR at practically high Vbias.
The BMP‐SMAD pathway mediates the impaired hepatic iron metabolism associated with the ERFE‐A260S variant
Authors: Andolfo Immacolata , Rosato Barbara Eleni , Marra Roberta , De Rosa Gianluca , Manna Francesco , Gambale Antonella , Iolascon Achille , Russo Roberta 
Published: August 2019

AbstractThe erythroferrone (ERFE) is the erythroid regulator of hepatic iron metabolism by suppressing the expression of hepcidin. Congenital dyserythropoietic anemia type II (CDAII) is an inherited hyporegenerative anemia due to biallelic mutations in the SEC23B gene. Patients with CDAII exhibit marked clinical variability, even among individuals sharing the same pathogenic variants. The ERFE expression in CDAII is increased and related to abnormal erythropoiesis. We identified a recurrent low‐frequency variant, A260S, in the ERFE gene in 12.5% of CDAII patients with a severe phenotype. We demonstrated that the ERFE‐A260S variant leads to increased levels of ERFE, with subsequently marked impairment of iron regulation pathways at the hepatic level. Functional characterization of ERFE‐A260S in the hepatic cell system demonstrated its modifier role in iron overload by impairing the BMP/SMAD pathway. We herein described for the first time an ERFE polymorphism as a genetic modifier variant. This was with a mild effect on disease expression, under a multifactorial‐like model, in a condition of iron‐loading anemia due to ineffective erythropoiesis.
Modification of regenerated cellulose membrane by impregnation of silver nanocrystal clusters
Authors: Vakili Mohammad Reza , Gholami Mehrdad , Mosallaei Zahra , Ghasemi Abdol Madjid 
Published: August 2019

ABSTRACTRegenerated cellulose forms a very important class of basic material with diverse applications because of its hydrophilicity and insolubility in water. Thus, one of the applications of regenerated cellulose is used to fabricate membranes. However, short operational lifetime is one of the disadvantages of the regenerated cellulose. In this research, surface modification of the cellophane membrane was carried out by silver nanoclusters. Silver colloids were formed in situ by chemical and photochemical reduction, and then, silver particles were deposited uniformly onto the surface of the cellophane membrane. The maximum amount of silver deposition was found to be 2.55% by weight in this modification. The modified and unmodified membranes were characterized by X‐ray diffraction (XRD), scanning electron microscopy (SEM), and energy‐dispersive X‐ray analysis to indicate silver nanocrystalline cluster particles on the modified membrane. SEM images indicate well‐dispersed silver particles with an average size of 0.65 μm on the membrane. XRD patterns showed that the size of the silver crystals was 3.9 nm. The surface properties of modified and unmodified membranes were studied by the contact angle. Water absorption, oxidative resistance, salt permeability, and thermal stability were investigated. This study revealed that the modified membrane is more resistant against the oxidative cleavage than the unmodified one moreover, the salt permeability increased after the treatment. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48292.
Fabrication of ZnO‐functionalized polypyrrole microcomposite as a protective coating to enhance anticorrosion performance of low carbon mild steel
Authors: Satpal Sudhakar , Bhopale Abhijit , Deshpande Pravin , Athawale Anjali 
Published: August 2019

ABSTRACTIn the present work, PPy, ZnO, and polypyrrole/zinc oxide (PPy/ZnO) microcomposites (1, 2, and 5 wt%) were prepared and their properties have been tuned for anticorrosion applications on low carbon mild steel. The synthesized products: ZnO, PPy, and composites were characterized by various sophisticated analytical techniques such as XRD, FTIR, Raman, FESEM, EDX, UV–VIS, TGA, and BET. The band frequencies observed at 480 and 588 cm−1 in FTIR spectrum correspond to stretching vibrations of Zn‐O and N‐H bonds, respectively, broadening of the bands in the composites indicate strong interactions between ZnO and PPy matrix. The potentiodynamic polarization study of PPy and PPy/ZnO composite was carried out in 3.5% NaCl solution to investigate the corrosion resistance efficiency. PPy/1 wt% ZnO (Icorr = 190 nA) composite coating on low carbon mild steel was observed to exhibit best corrosion protection property compared to PPy (121 μA), 2 and 5 wt% ZnO (242, 295 nA) composites. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 48319.
Study on the ablative properties of ethylene propylene diene terpolymer/silsesquioxane insulation materials
Authors: Hao Huijuan , Zhou Xuyuan , Shen Zhaohong , He Jiyu , Yang Rongjie 
Published: August 2019

ABSTRACTOctaphenylsilsesquioxane (OPS), polyphenylsilsesquioxane (PPSQ), and octavinylsilsesquioxane (OVP) have been incorporated into ethylene propylene diene terpolymer (EPDM) in order to study their effects on the ablative properties of the respective EPDM composites. The results show that PPSQ and OVP serve as effective ablative additives for EPDM composites. The linear ablation rates of EPDM composites with 4.4 wt % OVP or PPSQ were reduced by 21 or 16.5%, respectively, compared with the control sample. Moreover, OVP and PPSQ also improved the flame retardancy and suppressed smoke emission. The heat release rate of EPDM composite with 4.4 wt % OVP was measured as 90.6 kW m−2, 17% lower than that of the control sample, and the same amount of PPSQ reduced the total smoke release from 1946 to 1497 m2 s−1. Thermogravimetric analysis results showed EPDM/OVP composite to leave a higher residual mass than the calculated value. Besides, scanning electron microscopy, cone calorimetry (CONE), and BET tests showed that the chars formed during the ablation of EPDM composites containing OVP and PPSQ had better structural stability and thermal stability owing to the fact that they were denser and more homogeneous. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48365.
Poly(methyl methacrylate) hybrid syntactic foams with hollow glass microspheres and polyhedral oligomeric silsesquioxanes
Authors: Ozkutlu Merve , Dilek Cerag , Bayram Goknur 
Published: August 2019

ABSTRACTThe study aims to produce poly(methyl methacrylate) (PMMA)‐based lower density syntactic foams with hollow glass microspheres (HGMs) and to improve their mechanical properties by the addition of polyhedral oligomeric silsesquioxanes (POSSs) while maintaining the thermal properties of the neat polymer. First to understand the effect of POSS addition, PMMA–POSS composites with octaisobutyl and octaphenyl POSS were produced through extrusion. Higher relative flexural and impact strengths were obtained with POSS addition to PMMA. Obtaining more enhanced properties with octaphenyl POSS, PMMA‐HGM‐POSS hybrid syntactic foams were prepared with this additive. In general, the specific flexural strength and modulus of the PMMA syntactic foams were improved with the POSS loading, while the lower density and thermal properties of the PMMA syntactic foams were maintained. PMMA hybrid syntactic foams with 15 wt % HGMs and 0.25 wt % POSS exhibited 37.6% improvement in the specific flexural modulus with respect to the neat PMMA. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48368.
Yellow resistant photosensitive resin for digital light processing 3D printing
Authors: Cheng Qingkui , Zheng Yan , Wang Tao , Sun Dongli , Lin Runxiong 
Published: August 2019

ABSTRACTDigital light processing (DLP) has been studied and developed in the field of three‐dimensional (3D) printing in recent years due to its fast curing rate and high resolution. To reduce the cost and viscosity of the resin system, the aromatic polyurethane acrylates (PUAs) were used as oligomer. The matrix resin called PUH2consists of oligomers (PUA, bisphenol A polyoxyethylene ether dimethyl acrylate) and active diluents (hydroxyethyl acrylate, hydroxyethyl methacrylate). However, the photosensitive resin containing aromatic isocyanate groups was easily yellowed under ultraviolet light. In this article, we developed a resin for DLP 3D printing with yellowing resistance, excellent mechanical properties and high heat resistance. The optimal ratio of 3DP‐PUH2resin was PUH2/TPO/RYOJI‐292/dye/nanosilica = 100/5/0.4/0.01/0.1, and its viscosity was 500 cp, which is suitable for DLP 3D printing. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2020,137, 48369.