bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental and numerical study of water spray system for a fire event in a confined and mechanically ventilated compartment
Authors: Vaux Samuel , Prétrel Hugues , Audouin Laurent
Published: June 2019

The present work addresses the application of a water spray system in case of a fire event in large‐scale experiments for nuclear safety issues. It focuses on the interaction between a water spray system and a stratified smoke layer due to a pool fire in a mechanically ventilated enclosure. This study is supported by a set of four large‐scale tests and one numerical simulation with a 3D CFD software, named CALIF3S/ISIS, and developed by the French Institut de Radioprotection et de Sûreté Nucléaire (IRSN). The modelling used in this paper is based on an Eulerian‐Lagrangian approach. The fire tests are performed in a 165  −m3 mechanically ventilated single room. The fire is a lubricant oil pool fire of about 400 kW. The ventilation flow rate is 2550 m3.h−1 and corresponds to a renewal rate of 15.5 h−1. The spray nozzles are deluge and sprinkler type. The test parameters are the water flow rate, the time of activation, and the duration of activation. Based on the large‐scale experiments and the numerical simulation, four typical physical mechanisms have been enlightened. The first one corresponds to the cooling of the gas phase that is the straightforward consequence of the heat transfer exchange between the water droplets and the surrounding gas. The second effect is the process of gas mixing and homogenization induced by the water spraying system. The gas concentrations (O2, CO2) in the upper and lower parts of the room tend to the same level. The third effect is the significant increase of the fire heat release rate (HRR), up to 25 %, when the water spray is activated. Then, the last noteworthy effect is the occurrence of gas pressure peaks when the water spray is activated or shut off, consequence of the sudden change of the gas temperature. The processes of gas cooling and fire HRR increase are showed to be the main causes of these variations of gas pressure.
Loading lime by‐product into derivative cellulose carrier for food enrichment
Authors: Afkhami Rana , Goli Mohammad , Keramat Javad
Published: June 2019

The objective here is to enrich orange juice through encapsulated lime by‐product extract (LBE) through freeze‐drying, in order to increase lime by‐product consumption, in addition to increasing nutrition value of orange juice. The properties of both the LBE and microparticles are measured. The total polyphenolic compound (TPC) was measured to be 34.5 ± 0.5 (mg gallic acid/g LBE). The obtained value of encapsulation efficiency (EE) was within the 55%–70% range. The encapsulation method was satisfactory. The particle size is within 10–21 μm range, and differences between all treatments were statistically notable (p < 0.05). The lack of melting peaks in the thermal profiles by differential scanning calorimeter (DSC) of microparticles confirmed that hesperidin was well embedded in the polymeric cover. According to the sensory evaluations of orange juice which was enriched with LBE microparticles, the bitter taste was not perceived in some treatments.
A Facile Electrochemical Method for Graphene Nanoplatelets Preparation Using Multi‐walled Carbon Nanotubes
Authors: Danilov M. O. , Rusetskii I. A. , Slobodyanyuk I. A. , Dovbeshko G. I. , Khyzhun O. Y. , Strelchuk V. V. , Kolbasov G. Ya.
Published: June 2019

We report on facile method of graphene nanoplatelets synthesis by electrochemical method using multi‐walled carbon nanotubes (MWCNTs). For the synthesis procedure we utilize standard redox potential of the carbon atom belonging to carboxyl groups. The graphene oxide was obtained by anodic oxidation of MWCNTs in 80% sulfuric acid at optimum oxidation potential +3.0 V for 4 h. The subsequent electrochemical reduction of the obtained material was carried out in an alkaline medium. The successful electrochemical production of the graphene nanoplatelets from MWCNTs was confirmed by different experimental techniques, in particular TEM, XRD, XPS, XES, FTIR and Raman spectroscopy. The current‐voltage characteristics of the oxygen electrodes produced from the electrochemically obtained graphene nanoplatelets were investigated. It was shown that the graphene nanoplatelets produced by electrochemical method is a promising material for fuel cell electrodes.
The Effect of Potential Cycling on High Temperature PEM Fuel Cell with Different Flow Field Designs
Authors: Bandlamudi V. , Bujlo P. , Linkov V. , Pasupathi S.
Published: June 2019

Degradation of phosphoric acid doped polybenzimidazole membrane based fuel cells under accelerated potential cycling conditions is investigated in current study. Three unit cells with identical high temperature membrane electrode assembly were assembled with three different cathode flow field designs. The fuel cell is cycled between 0.5 V and 0.9 V with 3 min dwelling time for each voltage set point. Performance degradation mechanisms associated with differences in cathode flow design are identified. The fuel cell with multiple serpentine design is operated for a maximum of 4,821 potential cycles with only 38.6% of initial performance remaining at the end‐of‐test (EoT), whereas straight and parallel design operated for only 3,188 cycles. The electrochemical characterization studies reveal the cause of observed performance losses from polarization curves. Irrespective of the design type used there are very high activation losses observed which accelerated with accelerated stress tests (AST) testing. The impedance studies reveal high charge transfer resistance related to increased platinum crystal growth on cathode and reduced electrochemical surface area (ECSA) of catalyst. Overall the AST results in irreversible performance loss and severe degradation of the cathode catalyst support and catalyst itself.
Are U.S. trends a barometer of future cancer transitions in emerging economies?
Authors: Vaccarella Salvatore , Bray Freddie
Published: June 2019

The currently high cancer incidence rates in the U.S. and other high‐income countries have been strongly affected by the acquisition of environmental and lifestyle risk factors that accompanied socioeconomic growth in the second half of the last century. The very same factors are now operating in many low‐ and middle‐income countries (LMIC) undergoing rapid socioeconomic transition. A parallel is drawn between the past cancer trends in the U.S. and those anticipated in LMIC transitioning towards higher levels of socioeconomic development. We expect to see a major upsurge in the (still low to intermediate) cancer incidence and mortality rates in LMIC over the next decades, which coupled with population aging and growth, would translate to a scale of individuals diagnosed with, living and dying from cancer unparalleled in history. On account of resource constraints and organizational limitations, prevention strategies need to be prioritized in LMIC.
Acquired resistance to EGFR tyrosine kinase inhibitors is mediated by the reactivation of STC2/JUN/AXL signaling in lung cancer
Authors: Liu Yi‐Nan , Tsai Meng‐Feng , Wu Shang‐Gin , Chang Tzu‐Hua , Tsai Tzu‐Hsiu , Gow Chien‐Hung , Chang Yih‐Leong , Shih Jin‐Yuan
Published: June 2019

Constitutive activation of the epidermal growth factor receptor (EGFR) signaling pathway is implicated in the initiation and progression of lung cancer. EGFR tyrosine kinase inhibitor (TKI)‐targeted therapy has become the standard treatment for nonsmall cell lung cancer (NSCLC) patients. However, acquired resistance to these agents remains a major obstacle for managing NSCLC. Here, we investigated a novel strategy to overcome EGFR TKI resistance by targeting the stanniocalcin 2 (STC2)‐JUN‐AXL pathway. We revealed that STC2 was expressed at significantly higher levels in EGFR TKI‐resistant cells. Further, clinical analysis showed that STC2 expression was increased after the development of EGFR TKI resistance and that higher levels were correlated with shorter progression‐free survival in EGFR TKI‐treated lung cancer patients. Moreover, STC2 overexpression in EGFR TKI‐sensitive cells resulted in EGFR TKI resistance. Conversely, genetic silencing of STC2 rendered EGFR TKI‐resistant cells more sensitive to EGFR TKIs. Mechanically, STC2 enhanced AXL promoter activity by increasing the phosphorylation of c‐Jun, which is an indispensable transcription factor that transactivates AXL. STC2 promoted activation of the JUN‐AXL‐extracellular signal‐regulated kinase (ERK) signaling axis in lung cancer cells. Pharmacological or genetic inhibition of AXL‐ERK activity inhibited STC2‐mediated EGFR TKI resistance. We also demonstrated that PE2988 cells, a C797S‐independent osimertinib‐resistant primary cancer cell line from a lung cancer patient, responded to combined AXL inhibitor and osimertinib treatment. In conclusion, our research indicates that STC2 overexpression is important for acquired resistance to EGFR TKIs and that STC2‐JUN‐AXL‐ERK signaling might be a potential therapeutic target to overcome resistance to EGFR TKIs.
Factor analysis of the heterosexist harassment, rejection, and discrimination scale in lesbian, gay, bisexual, transgender, and queer people of colour
Authors: Smith Erin R. , Perrin Paul B. , Sutter Megan E.
Published: June 2019

The factor structure of the Heterosexist Harassment, Rejection, and Discrimination Scale (HHRDS) was examined in lesbian, gay, bisexual, transgender, and queer (LGBTQ) people of colour. Two hundred participants completed a survey with the HHRDS and several mental health scales. A confirmatory factor analysis suggested the original HHRDS structure fit the data poorly. Exploratory factor analyses found a different 2‐factor structure, consisting of harassment/rejection and family discrimination. Convergent validity analyses demonstrated that family discrimination had the largest association with depression and anxiety, indicating that family discrimination may be particularly salient among LGBTQ people of colour. This study supports the use of the HHRDS in racially/ethnically diverse samples, but with a slightly different factor structure. Examining discriminatory experiences from family members is an important direction for future research in LGBTQ people of colour.
Efficiency in functional analysis of problem behavior: A quantitative and qualitative review
Authors: Saini Valdeep , Fisher Wayne W. , Retzlaff Billie J. , Keevy Madeleine
Published: June 2019

Originating in the mid‐1960s, functional analysis (FA) has become the gold standard method for understanding the environmental variables that come to shape and maintain problematic behaviors such as aggression, self‐injury, and property destruction. Over the decades, a number of studies have refined FA methods, attempting to improve the overall efficiency of the analysis through experimental design and procedural modifications. In the present review, we used ongoing visual‐inspection criteria and basic probability theory to compare and analyze levels of efficiency across FA types. The multielement design and synthesized contingency analyses were about equally efficient with respect to the mean number of sessions conducted per function tested, and the trial‐based and synthesized contingency analyses were the 2 most efficient with respect to the mean duration per function tested. We discuss the implications of these findings in the broader context of efficiency and provide recommendations for maximizing efficiency during an FA. We also discuss other qualitative procedural details that may influence the overall efficiency of an FA.
Zn‐incorporation with graphene oxide on Ti substrates surface to improve osteogenic activity and inhibit bacterial adhesion
Authors: Tao Bailong , Chen Maowen , Lin Chuanchuan , Lu Lu , Yuan Zhang , Liu Ju , Liao Qiang , Xia Zengzilu , Peng Zhihong , Cai Kaiyong
Published: June 2019

The poor osseointegration and postoperative bacterial infection are prominently responsible for the failure of titanium (Ti)‐based implant in clinic. To address above issues, methacryloyl modified graphene oxide (GOMA) as zinc ions (Zn2+) reservoir and release platform was fabricated on the Ti substrates with cathode electrophoresis deposition (EPD). Afterward, phenylboronic acid (PBA) functionalization methacryloyl‐gelatin (GelMA‐PBA) was reacting with GOMA through in situ free‐radical polymerization to prepare GO‐Zn/GelMA‐PBA coating. The obtained coating was confirmed by scanning electron microscopy, X‐ray photoelectron spectroscopy, and Zn ions release property, respectively. in vitro cellular experiments including cell activity, alkaline phosphatase, collagen secretion, extracellular matrix (ECM) mineralization, osteogenic genes and proteins, revealed that GO‐Zn/GelMA‐PBA coating was beneficial for enhancing the adhesion, proliferation, and differentiation of osteoblasts. The positive results were related to the existence of gelatin, formation of boronic ester between PBA groups, and carbohydrates of osteoblasts surface. Meanwhile, antibacterial assay against Staphylococcus aureus and Pseudomonas aeruginosa confirmed that GO‐Zn/GelMA‐PBA coating on Ti substrates had superior antibacterial capacity, availably inhibited the bacterial adhesion, and prevented formation of biofilm. Hence, the study provides a promising strategy for designing pro‐osteogenesis and antibacterial coating on Ti substrates for orthopedic applications.
Can Classification and Regression Tree Analysis Help Identify Clinically Meaningful Risk Groups for Hip Fracture Prediction in Older American Men (The MrOS Cohort Study)?
Authors: Su Yi , Kwok Timothy C Y , Cummings Steven R , Yip Benjamin H K , Cawthon Peggy M
Published: June 2019

Although the WHO fracture risk algorithm (FRAX) is used to predict fracture, the utility of some simple machine‐learning methods, such as classification and regression trees (CARTs) should be evaluated to determine their efficacy in fracture prediction. Follow‐up time for the hip fracture analyses of 5977 community‐dwelling American men aged ≥65 years old was truncated to 10 years. There were 172 (2.9%) men who had an incident nontraumatic hip fracture. The CARTs were developed using hip BMD and common clinical risk factors as follows: model 1 = using classification with continuous variables of age, total hip BMD, and femoral neck BMD, or together with common clinical risk factors; and model 2 = using classification with continuous variables of age, total hip BMD, femoral neck BMD, FRAX score, osteoporosis by T‐score at the hip, and common clinical risk factors. The predictive performance of risk models derived from CARTs was compared with the basic classification of FRAX at 3% (basic model). From model 1, discriminators selected by CART were total hip BMD, age, and femoral neck BMD; no other clinical risk factors were selected. From model 2, discriminators selected by CART were FRAX score, femoral neck BMD, and age. Compared with the basic model using only a high‐risk group by FRAX ≥3%, no significantly improved predictive performance was demonstrated by model 1 or model 2 as identified by CART with the area under the receiver‐operating characteristic curve for each model of 0.714 (95% CI, 0.676 to 0.751) or 0.726 (95% CI, 0.690 to 0.762) versus 0.703 (95% CI, 0.667 to 0.740), respectively. The improved overall net reclassification improvement index was 0.02 (95% CI, –0.04 to 0.08) and 0.05 (95% CI, –0.01 to 0.10), respectively. Although a FRAX category is a good clinical indicator for hip fracture risk, a simple classification by age and BMD may provide an alternative way to estimate a clinical risk level of 3.0%. © 2019 The Authors. JBMR Plus is published by Wiley Periodicals, Inc. on behalf of the American Society for Bone and Mineral Research.
miR‐21‐5p inhibits neuropathic pain development via directly targeting C‐C motif ligand 1 and tissue inhibitor of metalloproteinase‐3
Authors: Zhong Liang , Xiao Weimin , Wang Fang , Liu Juan , Zhi Li‐Jun
Published: June 2019

MicroRNAs (miRNA) play important roles in neuroinflammation and neuropathic pain development; however, the underlying mechanism requires further investigation. The expression of miR‐21‐5p was remarkably upregulated in chronic constrictive injury (CCI) rat model. A significant alleviated neuropathic pain development and reduced the expression of cytokines was observed in CCI rat after exogenous injection of miR‐21‐5p mimic. The dual‐luciferase analysis revealed that tissue inhibitor of metalloproteinase‐3 (TIMP3) and chemokines C‐C motif ligand 1 (CCL1) was direct downstream target of miR‐21‐5p. Moreover, silencing of TIMP3 and CCL1 could rescue mechanical allodynia, thermal hyperalgesia and cytokine release in CCI rat, suggesting that TIMP3 and CCL1 exert their function by mediating neuroinflammation in neuropathic pain development. Therefore, we have identified a novel miR‐21‐5p–CCL1/TIMP3‐cytokine axis in regulation of neuropathic pain development in CCI rat model, which is valuable for enhancing our understanding of neuropathic pain and developing miRNAs as potential therapeutic options in the future.
lncRNA MEG3 modified epithelial‐mesenchymal transition of ovarian cancer cells by sponging miR‐219a‐5p and regulating EGFR
Authors: Wang Lei , Yu Mingxin , Zhao Shanshan
Published: June 2019

This study was aimed to verify whether there existed any associations between long noncoding RNA MEG3/miR‐219a‐5p/EGFR axis and the development of ovarian cancer (OC). As a whole, we gathered 317 pairs of OC tissues and surgical marginal normal tissues and simultaneously acquired four OC cell lines (ie, A2780, Caov‐3, OVCAR‐3, and SKOV‐3) and human normal ovarian surface epithelial cell line. Moreover, pcDNA3.1‐MEG3, si‐MEG3, miR‐219a‐5p mimic, miR‐219a‐5p inhibitor, pcDNA3.1‐EGFR, and si‐EGFR were, respectively, transfected into the OC cells, and their impacts on viability, proliferation, apoptosis, invasion, and migration of OC cells were assessed via conduction of MTT assay, colony formation assay, flow cytometry assay, transwell assay, and scratch assay. Ultimately, dual‐luciferase reporter gene assay was performed to testify the targeted relationships among maternally expressed gene 3 (MEG3), miR‐219a‐5p, and estimated glomerular filtration rate (EGFR). It was indicated that underexpressed MEG3 and miR‐219a‐5p were significantly associated with unfavorable prognosis of patients with OC when compared with overexpressed MEG3 and miR‐219a‐5p (P < .05). In addition, the OC cells transfected with si‐MEG3 or miR‐219a‐5p inhibitor exhibited stronger viability, proliferation, invasion, and migration than untreated cells (P < .05). Correspondingly, the apoptotic percentage of OC cells was reduced observably under treatments of si‐MEG3 and miR‐219a‐5p inhibitor (P < .05). Moreover, MEG3 exerted modulatory effects on the expression of miR‐219a‐5p (P < .05), and there was a sponging relationship between them (P < .05). Finally, EGFR expression was modified by both MEG3 and miR‐219a‐5p significantly (P < .05), and raising EGFR expression could changeover the impacts of MEG3 and miR‐219a‐5p on the above‐mentioned activity of OC cells (P < .05). Conclusively, MEG3 could serve as a promising biomarker for diagnosis and treatment of OC, considering its involvement with OC etiology via regulation of miR‐219a‐5p/EGFR axis.
Computational design and evaluation of β‐sheet breaker peptides for destabilizing Alzheimer's amyloid‐β42 protofibrils
Authors: Shuaib Suniba , Narang Simranjeet Singh , Goyal Deepti , Goyal Bhupesh
Published: June 2019

The β‐sheet breaker (BSB) peptides interfere with amyloid fibril assembly and used as therapeutic agents in the treatment of Alzheimer's disease (AD). In this regard, a simple yet effective in silico screening methodology was applied in the present study to evaluate a potential 867 pentapeptide library based on known BSB peptide, LPFFD, for destabilizing Aβ42 protofibrils. The molecular docking based virtual screening was used to filter out pentapeptides having binding affinities stronger than LPFFD. In the next step, binding free energies of the top 10 pentapeptides were evaluated using the MM‐PBSA method. The residue‐wise binding free energy analysis reveals that two pentapeptides, PVFFE, and PPFYE, bind to the surface of Aβ42 protofibril and another pentapeptide, PPFFE, bind in the core region of Aβ42 protofibril. By employing molecular dynamics simulation as a post filter for the top‐hit peptides from MM‐PBSA, the pentapeptides, PPFFE, PVFFE, and PPFYE, have been identified as potential BSB peptides for destabilizing Aβ42 protofibril structure. The conformational microstate analysis, a significant decrease in the β‐sheet content of Aβ42 protofibril, a loss in the total number of hydrogen bonds in Aβ42 protofibril, Asp23‐Lys28 salt bridge destabilization and analysis of the free energy surfaces highlight Aβ42 protofibril structure destabilization in presence of pentapeptides. Among three top‐hit pentapeptides, PPFFE displayed the most potent Aβ42 protofibril destabilization effect that shifted the energy minima toward lowest value of β‐sheet content as well as lowest number of hydrogen bonds in Aβ42 protofibril. The in silico screening workflow presented in the study highlight an alternative tool for designing novel peptides with enhanced BSB ability as potential therapeutic agents for AD.
Key candidate genes associated with BRAFV600E in papillary thyroid carcinoma on microarray analysis
Authors: Yu Xiaqing , Zhong Peng , Han Yali , Huang Qingqing , Wang Jian , Jia Chengyou , Lv Zhongwei
Published: June 2019

The mechanisms of B‐type Raf kinase (BRAF) V600E mutation in papillary thyroid cancer (PTC) remain to be elucidated. With the aim to investigate the key candidate genes distinctive to BRAFV600E‐PTC, we analyzed the transcriptomics data from three microarray datasets (GSE27155, GSE54958, and GSE58545) and identified 491 differentially expressed genes (DEGs) between BRAFV600E‐PTC and BRAFwild type‐PTC. Functional enrichment analysis of DEGs revealed that negative regulation of wound healing may be involved in the BRAFV600E‐related pathogenesis in PTC. Weighted gene coexpression network analysis revealed BRAFV600E‐related coexpressed genes in PTC, from which hub genes were selected. The intersection of DEGs and hub genes revealed 31 candidates, wherein GRB7, SNAP25, SLC35F2, FAM155B, HGD, and ITPR1 were rendered the key candidate genes via receiver operating characteristic curve analysis. On further characterization, the six key genes displayed significantly different expression patterns at different cytomorphology, however, with no significant difference in overall survival. These results provide novel insights into the key genes distinctive to of BRAFV600E in PTC and might be suggestive as therapeutic targets for further application.
Association of Metformin Use With End‐Stage Renal Disease in Patients With Type 2 Diabetes Mellitus: A Nationwide Cohort Study Under the Pay‐for‐Performance Program
Authors: Lee Ming‐Chia , Lee Chih‐Hsin , Chang Lih‐Yu , Chang Chia‐Hao , Zhang Jun‐Fu , Lee Meng‐Rui , Wang Jann‐Yuan , Chen Shih‐Ming
Published: June 2019

Animal studies have demonstrated that metformin exerts a renoprotective effect. Human studies of patients with diabetes mellitus (DM) regarding the association of metformin use with end‐stage renal disease (ESRD) are lacking. Patients with type 2 DM and without a history of kidney disease who were enrolled under the pay‐for‐performance program of the National Health Insurance in Taiwan were identified. Those who received ≥90 cumulative defined daily doses of metformin within 1 year were selected (metformin users) and compared with a 1:1 propensity score–matched metformin nonuser cohort. Primary and secondary outcomes were development of ESRD and chronic kidney disease (CKD), respectively. Independent predictors were investigated using Cox regression analysis. A total of 24 158 pairs of metformin users and nonusers were enrolled, with an incidence of ESRD of 1908 and 1723 and CKD of 1095 and 1056 cases per 100 000 person‐years, respectively. Metformin use was independently associated with increased risks of ESRD (adjusted hazard ratio, 1.22; 95% confidence interval, 1.12‐1.32) and CKD (adjusted hazard ratio, 1.25; 95% confidence interval, 1.12‐1.40) in a dose‐response relationship. Patients with hypertension plus nonuse of angiotensin‐converting enzyme inhibitors or angiotensin II receptor blockers potentiated kidney damage by metformin. In patients with DM, use of metformin may increase the risk of ESRD and CKD. Health care professionals should be alert and closely monitor renal function when prescribing metformin.
Creating Brand Meaning: A Review and Research Agenda
Authors: Batra Rajeev
Published: June 2019

In this paper I review, from the perspective of experimental research, studies that have examined how brands acquire cultural meaning, and suggest future research directions. McCracken's (Journal of Consumer Research, 13, 1986 and 71) model of the meaning transfer process gained influence about thirty years ago, but experimental studies of the processes it posited have been limited in their scope. The review is organized around three questions. First, what should be the dependent variables: the types of meanings that can adhere to brands? Second, what have we learned from studies on the types of visual, sensory, and human cues that are the sources of particular types of brand meaning—our independent variables? Third, what do we know, and need to know, about the inferential and other processes through which consumers “take possession” of these brand meanings from these cues? The review concludes with a research agenda.
Minimalist approach meets green chemistry: Synthesis of18F‐ labeled (hetero)aromatics in pure ethanol
Authors: Zlatopolskiy Boris D. , Zischler Johannes , Krapf Philipp , Richarz Raphael , Lauchner Katharina , Neumaier Bernd
Published: June 2019

The application of toxic solvents and additives is inevitable for most of the described protocols for18F‐labeling. Herein, a novel “green” procedure for nucleophilic aromatic radiofluorination of highly activated (hetero)aromatic substrates in pure EtOH is described. Using this method a series of18F‐labeled (hetero)arenes have been synthesized in radiochemical yields (RCYs) of up to 97%.
Preparation and application of molecularly imprinted polymer solid‐phase microextraction fiber for the selective analysis of auxins in tobacco
Authors: Zhang Qing , Fan Liangbiao , Lu Qiaomei , Yu Xiaozhang , Liang Meina , Nie Jinfang , Li Ningjie , Zhang Lan
Published: June 2019

As signal molecules, auxins play an important role in mediating plant growth. Due to serious interfering substances in plants, it is difficult to accurately detect auxins with traditional solid‐phase extraction methods. To improve the selectivity of sample pretreatment, a novel molecularly imprinted polymer ‐coated solid‐phase microextraction fiber, which could be coupled directly to high‐performance liquid chromatography, was prepared with indole acetic acid as template molecule for the selective extraction of auxins. The factors influencing the polymer formation, such as polymerization solvent, cross‐linker, and polymerization time, were investigated in detail to enhance the performance of indole acetic acid‐molecularly imprinted polymer coating. The morphological and chemical stability of this molecularly imprinted polymer‐coated fiber was characterized by scanning electron microscopy, infrared spectrometry, and thermal analysis. The extraction capacity of the molecularly imprinted polymer‐coated solid‐phase microextraction fiber was evaluated for the selective extraction of indole acetic acid and indole‐3‐pyruvic acid followed by high‐performance liquid chromatography analysis. The linear range for indole acetic acid and indole‐3‐pyruvic acid was 1–100 µg/L and their detection limit was 0.5 µg/L. The method was applied to the simultaneous determination of two auxins in two kinds of tobacco (Nicotiana tabacum L and Nicotiana rustica L) samples, with recoveries range from 82.1 to 120.6%.
PSMD4 regulates the malignancy of esophageal cancer cells by suppressing endoplasmic reticulum stress
Authors: Ma Ai‐Guo , Yu Li‐Mei , Zhao Hong , Qin Cun‐Wei , Tian Xiang‐Yu , Wang Qing
Published: June 2019

Proteasome 26S subunit non‐ATPase 4 (PSMD4) is an important proteasome ubiquitin receptor and plays a key role in endoplasmic reticulum stress (ERS). However, the study of PSMD4 in esophageal cancer (EC) is relatively rare. Here, we found that the expression of PSMD4 was markedly enhanced in EC tissues and cell lines. The cell counting kit‐8 (CCK‐8) assay showed that overexpression of PSMD4 significantly enhanced Eca109 cell viability, while inhibition of PSMD4 reduced Eca109 cell viability. Knockdown of PSMD4 induced Eca109 cell apoptosis and cell cycle arrest. More importantly, knockdown of PSMD4 significantly enhanced the expression of glucose regulated protein 78, activating transcription factor 6, and p‐protein kinase R‐like ER kinase, indicating an enhanced ERS response in esophageal cancer cells. Compared with the control cells, brefeldin A significantly inhibited the expression of PSMD4 and increased the expression of p53‐upregulated modulator of apoptosis. However, such effects were largely reversed after overexpressing PSMD4 in Eca109 cells, suggesting that silencing PSMD4 could enhance ERS‐induced cell apoptosis. In summary, upregulation of PSMD4 promoted the progression of esophageal cancer mainly by reducing ERS‐induced cell apoptosis.
Hot corrosion Type II of FeCr‐based model alloys for boiler and heat exchanger applications
Authors: König Till , Montero Xabier , Galetz Mathias C.
Published: June 2019

The hot corrosion Type II of the alloys FeCr20, FeCr20Ni10, FeCr20Ni20, and FeCr20Co10 is investigated at 700°C in air + 0.5% SO2 with deposits consisting of Na2SO4 and a eutectic mixture of Na2SO4 and MgSO4 for 24, 100, and 300 h. The alloying elements nickel and cobalt have a positive influence when tests are conducted using a MgSO4‐Na2SO4 deposit. In this case, they reduce the metal loss and increase the time to the propagation stage. In contrast, when the alloys are exposed with a Na2SO4 deposit, these alloying elements increase the metal loss and allow for the transition to the propagation stage because they can form molten phases with the Na2SO4. During the incubation stage an oxide scale forms on the FeCr20 alloy, which is thicker than the one formed during exposure without a deposit, and iron oxides are observed, which precipitate in the deposit. The propagation stage occurs by a dissolution and precipitation mechanism forming localized pitting attack. Iron is the main species that dissolves and precipitates, while chromium remains mainly as an oxide beneath the initial surface. The additional elements are found in the pit and in the salt deposit.
Directed Printing and Reconfiguration of Thermoresponsive Silica‐pNIPAM Nanocomposites
Authors: Guo Yusheng , Belgodere Jorge A. , Ma Yingzhen , Jung Jangwook P. , Bharti Bhuvnesh
Published: June 2019

Printing of polymeric composites into desired patterns and shapes has revolutionized small‐scale manufacturing processes. However, high‐resolution printing of adaptive materials that change shape in response to external stimuli remains a significant technical challenge. The article presents a new approach of printing thermoresponsive poly(N‐isopropylacrylamide) into macroscopic structures that dynamically reconfigure in response to heating and cooling cycles. The printing process is performed using an external laser source, which enables thermal cross‐linking of the polymer ink consisting of monomer, cross‐linker, initiator, and inorganic nanoparticles. It is shown that the addition of silica nanoparticles enhances the mechanical properties of poly(N‐isopropylacrylamide) while maintaining its thermoresponsiveness at micrometer‐scale resolution, which otherwise is not feasible by extrusion‐based three‐dimensional printing techniques. It is demonstrated that spatial reconfiguration of the printed monolayers upon increasing temperature is governed by the local geometry, which enables mimicking the reconfiguration of plant leaves in a natural environment. The study lays a foundation for developing a new fabrication platform to print thermoresponsive structures that may find applications in biomedical implants, sensors, and other multi‐responsive materials.
Frequency of GJB2 mutations, GJB6‐D13S1830 and GJB6‐D13S1854 deletions among patients with non‐syndromic hearing loss from the central region of Iran
Authors: Naddafnia Hossein , Noormohammadi Zahra , Irani Shiva , Salahshoorifar Iman
Published: June 2019

Background

In the present study, we investigate the prevalence of the GJB2 gene mutations, and deletions in the GJB6 gene, namely del (GJB6‐D13S1830) and del (GJB6‐D13S1854), in patients with autosomal recessive non‐syndromic hearing loss (ARNSHL) from the central region of Iran.

Methods

One hundred and thirty‐one unrelated ARNSHL cases from the central part of Iran were recruited. Among them, 81% (106 cases) had at least two affected relatives. Coding and noncoding regions of the GJB2 gene were sequenced. Multiplex PCR was used for analysis of del (GJB6‐D13S1830) and del (GJB6‐D13S1854) deletions in GJB6.

Results

The GJB2 variants were found in 16.79% (22/131) of the patients. The pathogenic variants were 21/131 (16.03%). The nonpathogenic variants were 1/131 (0. 07%). Allele frequency of the c.35delG as the pathogenic variant was the most common with 59.52% (25/42). The remaining pathogenic variants were c.235delC, p.T8M, p.R32H, p.R143Q, p.R143W, c‐23+1G>A. The only nonpathogenic variant was polymorphism p.V27I. Further segregation analysis showed that variant of p.R143Q might have incomplete penetrance. None of the patients had targeted deletions in the GJB6 gene.

Conclusion

In comparison with reports from other areas of Iran, c.35delG demonstrates the highest frequency within the central region (accounting for 57.14% of cases), probably resulting from the founder effect and consanguineous marriage. The pathology of ARNSHL in such patients could be attributed to defects in Connexin 26 encoded by GJB2.
Treatment for postchemoradiotherapy hypopharyngeal stenosis: Pharyngoesophageal bypass using an anterolateral thigh flap—A case report
Authors: Larrañaga Juan J. , Boccalatte Luis A. , Picco Pedro I. , Cavadas Demetrio , Figari Marcelo F.
Published: June 2019

Radiation‐induced pharyngoesophageal stenosis is a frequent and unwanted consequence of nonsurgical treatment of hypopharyngeal carcinomas. Current treatment mainly includes endoscopic dilatations, but a poor response to this modality and/or a severe stenosis may lead to a radical resection (pharyngolaryngectomy) and reconstruction with tubed flaps, which allow oral feeding but fail to preserve speech. In this report, we present a case of radiation‐induced hypopharyngeal stenosis treated with a pharyngoesophageal bypass using an anterolateral thigh (ALT) flap with the intention of preserving the larynx. We describe the case of a 59‐year‐old male with severe pharyngoesophageal stenosis after chemoradiotherapy due to a squamous cell carcinoma, where conventional dilatation treatment failed to restore pharyngoesophageal passage of solids or liquids. Since the patient rejected a pharyngolaryngectomy due the loss of speech entailed, a pharyngoesophageal bypass was performed using an ALT flap. The flap measured 13 × 20 cm, which ensured a 4‐cm‐diameter tube and enough length to communicate the lateral pharyngeal wall with the cervical esophagus. Endoscopy did not reveal flap failure, and during the immediate postoperative period, the patient had a small cervical leak detected only by imaging that did not affect the skin and resolved with antibiotic treatment. The patient also required a tracheostomy on day 4 and initially had no passage of saliva through the bypass; we attributed this to edema that resolved spontaneously after 1 month with complete liquid and solid passage and laryngeal competence that led to tracheal decannulation. Good functional results were achieved both for speech and swallowing at 5‐year follow‐up. We believe that this procedure may be considered before performing a pharyngolaryngectomy for the treatment of a persistent benign stenosis in patients with a functional larynx.
Photonic radiofrequency receiver utilizing a phase modulator and a tunable single sideband optoelectronic oscillator
Authors: Xiao Kang , Jin Xiaofeng , Shen Xiaoqing , Cong Bo , Jin Xiangdong , Yu Xianbin , Zheng Shilie , Zhang Xianmin
Published: June 2019

A photonic radiofrequency (RF) receiver utilizing a phase modulator (PM) and a tunable single sideband (SSB) optoelectronic oscillator (OEO) is proposed and experimentally demonstrated. In this scheme, the RF signal to be detected is modulated on the PM in one optical path, while a local oscillation (LO) signal is optically generated by the SSB OEO in the other optical path. After combining two paths of optical signals via an optical coupler, an immediate frequency (IF) signal is obtained by photonic RF downconversion in a photodetector (PD). Through scanning the LO signal and monitoring the IF signal simultaneously, the input unknown RF signal can be detected. In the experiment, the RF tones with the operating frequency from 8.1 to 12.1 GHz are successfully detected. The minimum detectable RF power at 10.1 GHz is −84.6 dBm, and the spurious free dynamic range of the photonic RF receiver measured is about 73.8 dB/Hz2/3.
Integrated circuit (IC)‐embedded wafer‐level packaging technology for millimeter‐wave power ICs
Authors: Yook Jong‐Min , Sim Sanghoon , Park Bok‐Ju , Kim Dongsu , Kim Young‐Joon
Published: June 2019

A wafer‐level packaging (WLP) technology for millimeter‐wave power devices is presented, which features simple fabrication, low‐signal transition loss, and thermal consideration. Instead of using a rigid interposer, the proposed WLP technology incorporates thick copper sheet and an adhesive tape as the initial carrier. Short electroplated interconnection showed transition loss within 0.2 dB and return loss above 20 dB, at frequency range up to 30 GHz. We demonstrate the WLP with an RF power amplifier at 28 GHz. The power‐added efficiency (PAE) of the power amplifier packaged in the proposed technology is 30% at an output power of 27.5 dBm, which is identical to an unpackaged integrated circuit (IC) wire bonded on a printed circuit board. The size of the IC, and the final packaged sample was 2.2 × 1.5 × 0.1 mm3 and 3.3 × 2.4 × 0.2 mm3, respectively.
Flow of non‐Newtonian fluids in fractured porous media: Isogeometric vs standard finite element discretisation
Authors: Hageman Tim , de Borst René
Published: June 2019

A formulation has been derived for the flow of non‐Newtonian (power‐law) fluids in deformable, fractured porous media. The formulation is enhanced with a subgrid scale model to accurately represent the flow of the power‐law fluids inside the cracks. The resulting equations have been discretised using standard (Lagrangian) finite element shape functions and with non‐uniform rational B‐splines (NURBS), which have been cast into a standard finite element datastructure using Bézier extraction. The effect of the power‐law index on the velocity inside the fracture and on the total fluid flow through the porous medium has been analysed for a typical boundary‐value problem. It is shown that large differences between non‐Newtonian and linearised Newtonian fluids can occur for the fluid velocity inside the fracture. This can significantly influence the total fluid transport through the domain. A mesh sensitivity study has been carried out as well and shows that markedly smaller element sizes are required in order to obtain accurate results for the local flow inside the fracture, compared with the element sizes necessary for obtaining accurate results inside the porous medium away from the fracture. Moreover, a comparison has been made between the results obtained using standard Lagrange polynomials and those obtained using NURBS. It is shown that while both discretisation methods are able to accurately simulate the deformations and pressures in the porous medium, the higher interelement continuity of NURBS is mandatory for obtaining correct values of the fluid velocities inside the fracture, especially near the tips.
Space‐time finite element procedure with block‐iterative algorithm for dam‐reservoir‐soil interaction during earthquake loading
Authors: Sharma Vikas , Fujisawa Kazunori , Murakami Akira
Published: June 2019

This paper presents a time‐discontinuous Galerkin space‐time finite element method for the seismic analysis of dam‐reservoir‐soil system. For the reservoir domain an auxiliary variable q, a first‐order time derivative of hydrodynamic pressure is introduced as the primary unknown. Similarly, velocity is taken as the primary unknown in the solid domain. In this approach, secondary unknowns (displacement and pressure) are computed in a postprocessing step by consistent time integration of the primary unknowns. This arrangement leads to a system of linearly coupled algebraic equations, which is solved with a block‐iterative algorithm. In each iteration of the algorithm, two smaller linear systems, ie, one for velocity field and another for the auxiliary field, are solved separately and coupling between these two fields is enforced through iterations. Afterwards, numerical performance of the proposed scheme is demonstrated by solving some benchmark dam‐reservoir interaction problems. It is shown that very few iterations are required for the convergence. Lastly, the method is employed to analyze the effects of dynamic interactions on the response of concrete dam to the earthquake loading.
The Effects of Accountability Incentives in Early Childhood Education
Authors: Bassok Daphna , Dee Thomas S. , Latham Scott
Published: June 2019

In an effort to enhance the quality of early childhood education (ECE) at scale, nearly all U.S. states have recently adopted Quality Rating and Improvement Systems (QRIS). These accountability systems give providers and parents information about program quality and create both reputational and financial incentives for program improvement. However, we know little about whether these accountability reforms operate as theorized. This study provides the first empirical evidence on this question using data from North Carolina, a state with a mature QRIS. Using a regression discontinuity design, we examine how assignment to a lower quality rating influenced subsequent outcomes of ECE programs. We find that programs responded to a lower quality rating with comparative performance gains, including improvement on a multi‐faceted measure of classroom quality. Programs assigned to a lower star rating also experienced enrollment declines, which is consistent with the hypothesis that parents responded to information about program quality by selectively enrolling away from programs with lower ratings. These effects were concentrated among programs that faced higher levels of competition from nearby providers.
Distinctive ligand‐binding specificities of tandem PA14 biomass‐sensory elements from Clostridium thermocellum and Clostridium clariflavum
Authors: Grinberg Inna Rozman , Yaniv Oren , de Ora Lizett Ortiz , Muñoz‐Gutiérrez Iván , Hershko Almog , Livnah Oded , Bayer Edward A. , Borovok Ilya , Frolow Felix , Lamed Raphael , Voronov‐Goldman Milana
Published: June 2019

Cellulolytic clostridia use a highly efficient cellulosome system to degrade polysaccharides. To regulate genes encoding enzymes of the multi‐enzyme cellulosome complex, certain clostridia contain alternative sigma I (σI) factors that have cognate membrane‐associated anti‐σI factors (RsgIs) which act as polysaccharide sensors. In this work, we analyzed the structure‐function relationship of the extracellular sensory elements of Clostridium (Ruminiclostridium) thermocellum and Clostridium clariflavum (RsgI3 and RsgI4, respectively). These elements were selected for comparison, as each comprised two tandem PA14‐superfamily motifs. The X‐ray structures of the PA14 modular dyads from the two bacterial species were determined, both of which showed a high degree of structural and sequence similarity, although their binding preferences differed. Bioinformatic approaches indicated that the DNA sequence of promoter of sigI/rsgI operons represents a strong signature, which helps to differentiate binding specificity of the structurally similar modules. The σI4‐dependent C. clariflavum promoter sequence correlates with binding of RsgI4_PA14 to xylan and was identified in genes encoding xylanases, whereas the σI3‐dependent C. thermocellum promoter sequence correlates with RsgI3_PA14 binding to pectin and regulates pectin degradation‐related genes. Structural similarity between clostridial PA14 dyads to PA14‐containing proteins in yeast helped identify another crucial signature element: the calcium‐binding loop 2 (CBL2), which governs binding specificity. Variations in the five amino acids that constitute this loop distinguish the pectin vs xylan specificities. We propose that the first module (PA14A) is dominant in directing the binding to the ligand in both bacteria. The two X‐ray structures of the different PA14 dyads represent the first reported structures of tandem PA14 modules.
Internal Light‐Extraction Layers with Different Refractive Indices for Organic Light‐Emitting Diodes
Authors: Jung Sun-Gyu , Park Cheol Hwee , Park Soo Jong , Park Young Wook , Ju Byeong-Kwon
Published: June 2019

High‐performance organic light‐emitting diodes (OLEDs) require a light‐extraction layer either inside or outside the device. Herein, transparent metal oxides (MOs) of various refractive indices are inserted between the anode and glass as internal light‐extraction layers to improve the efficiency of the OLED device. Optical simulations are performed to reveal the optimal thicknesses for the light‐extraction layer of metal oxides of various refractive indices. Light‐extraction layers of metal oxides with optimized thickness are then used in OLED devices to evaluate the performance of devices. The device with the higher refractive index MO light‐extraction layer tends to show better device performance. Although the internal light‐extraction layer is inserted, the current flow in the device and the color coordinate variation depending on the viewing angle do not change significantly. These results are helpful in the development of optimized internal light‐extraction layers for individual colors and in the development of OLED displays with optimized light‐extraction layers for each pixel.
Fabrication of Conductive Patterns on 3D Printed Structure Using Photo‐Polymerization Technology
Authors: Choi Suyoung , Park MinSoo
Published: June 2019

3D printing technology is attracting considerable attention as it can be used to produce complex‐shaped structures quickly. Recently, in addition to the production of simple‐shaped parts, the manufacturing of embedded products with conductive patterns using 3D printing has increased. However, previous studies have limitations on conductivity, stability, and process complexity. Therefore, in this paper, a novel manufacturing process is proposed. It uses the same laser energy source of photo‐polymerization technology, which is a general 3D printing technology, to create a circuit pattern with high conductivity immediately after the structure is printed. This concept is based on two technologies: a laser direct structuring process and metal photo‐polymerization. Moreover, with this technique, it is possible to produce structures and conductive patterns using a single laser‐based machine. Therefore, alignment tolerance can be ignored during production. After additional metal deposition, the structure can achieve stable and high conductivity. The pattern produced by this novel manufacturing process has a resistance of 0.5 Ω cm–1, and the feasibility of the circuit is illustrated with a light‐emitting diode demonstration. This method is expected to be helpful for both shape production and the development of products that perform electrical functions.