bluuebunny/crossref_metadata_2025 huggingface dataset:
Going Public
Authors: Limbach Christoph
Published: May 2019

“Tierversuche verstehen”, an initiative of German research organisations, aims to actively and transparently inform the public about animal‐based research
The Secret Lives of Proteins
Authors: Unterstell Rembert
Published: May 2019

Sonja Lorenz studies a system that affects every cell in the body: the ubiquitin system. In the long term, her work could lead to improved therapeutic strategies / An encounter in Würzburg
Numerische Bestimmung der Standsicherheit von Böschungen unter Erdbebeneinwirkung am Beispiel eines Erddamms im Zentrifugenversuch
Authors: Hleibieh Jamal , Herle Ivo
Published: May 2019

Die Stabilität von Böschungen kann durch Erdbebeneinwirkungen stark beeinträchtigt werden. Obwohl das Böschungsverhalten unter Erdbeben sehr komplex ist, gehen die meisten Methoden in der Praxis von einer pseudostatischen Situation aus, bei der die dynamische Erdbebenwirkung durch eine zusätzliche statische Kraft ersetzt wird. In diesem Beitrag wird durch Nachrechnung eines Zentrifugenversuchs überprüft, inwieweit die pseudostatische Analyse das Versagen durch Unterschreiten des Grenzgleichgewichts abbilden kann. Anschließend wird das Potenzial der hypoplastischen Modelle durch eine dynamische Nachrechnung des Zentrifugenversuchs mit der Finite‐Elemente‐Methode (FEM) gezeigt. Weiterhin werden die mit der Hypoplastizität berechneten Ergebnisse dafür verwendet, eine Rückanalyse für die pseudostatische Methode durchzuführen. Damit lassen sich die Defizite dieser Methode veranschaulichen. Eine mögliche Kombination aus dynamischen FEM‐Berechnungen und der pseudostatischen Analyse zur Ermittlung eines realitätsnäheren Standsicherheitsfaktors wird diskutiert. Hierfür werden weitere dynamische Berechnungen mit einem elastoplastischen Stoffmodell durchgeführt.
Frontal atrophy as a marker for dementia conversion in Parkinson's disease with mild cognitive impairment
Authors: Chung Seok Jong , Yoo Han Soo , Lee Yang Hyun , Lee Hye Sun , Ye Byoung Seok , Sohn Young H. , Kwon Hunki , Lee Phil Hyu
Published: May 2019

This study aimed to investigate the cortical neural correlates of dementia conversion in Parkinson's disease with mild cognitive impairment (PD‐MCI). We classified 112 patients with drug‐naïve early stage PD meeting criteria for PD‐MCI into either PD with dementia (PDD) converters (n = 34) or nonconverters (n = 78), depending on whether they developed dementia within 4 years of PD diagnosis. Cortical thickness analyses were performed in 34 PDD converters and 34 matched nonconverters. Additionally, a linear discriminant analysis was performed to distinguish PDD converters from nonconverters using cortical thickness of the regions that differed between the two groups. The PDD converters had higher frequencies of multiple domain MCI and amnestic MCI with storage failure, and poorer cognitive performances on frontal/executive, memory, and language function domains than did the nonconverters. Cortical thinning extending from the posterior cortical area into the frontal region was observed in PDD converters relative to nonconverters. The discriminant analysis showed that the prediction model with two cortical thickness variables in the right medial superior frontal and left olfactory cortices optimally distinguished PDD converters from nonconverters. Our data suggest that cortical thinning in the frontal areas including the olfactory cortex is a marker for early dementia conversion in PD‐MCI.
The molecular landscape of the University of Michigan laryngeal squamous cell carcinoma cell line panel
Authors: Mann Jacqueline E. , Kulkarni Aditi , Birkeland Andrew C. , Kafelghazal Judy , Eisenberg Julia , Jewell Brittany M. , Ludwig Megan L. , Spector Matthew E. , Jiang Hui , Carey Thomas E. , Brenner J. Chad
Published: May 2019

Background

Laryngeal squamous cell carcinomas (LSCCs) have a high risk of recurrence and poor prognosis. Patient‐derived cancer cell lines remain important preclinical models for advancement of new therapeutic strategies, and comprehensive characterization of these models is vital in the precision medicine era.

Methods

We performed exome and transcriptome sequencing as well as copy number analysis of a panel of LSCC‐derived cell lines that were established at the University of Michigan and are used in laboratories worldwide.

Results

We observed a complex array of alterations consistent with those reported in The Cancer Genome Atlas head and neck squamous cell carcinoma project, including aberrations in PIK3CA, EGFR, CDKN2A, TP53, and NOTCH family and FAT1 genes. A detailed analysis of FAT family genes and associated pathways showed disruptions to these genes in most cell lines.

Conclusions

The molecular profiles we have generated indicate that as a whole, this panel recapitulates the molecular diversity observed in patients and will serve as useful guides in selecting cell lines for preclinical modeling.
HNRNPAB‐regulated lncRNA‐ELF209 inhibits the malignancy of hepatocellular carcinoma
Authors: Yang Yi , Chen Qing , Piao Hai‐Yan , Wang Biao , Zhu Gui‐Qi , Chen Er‐Bao , Xiao Kun , Zhou Zheng‐Jun , Shi Guo‐Ming , Shi Ying‐Hong , Wu Wei‐Zhong , Fan Jia , Zhou Jian , Dai Zhi
Published: May 2019

Our previous study demonstrated that heterogeneous nuclear ribonucleoprotein AB (HNRNPAB) is a key gene that facilitates metastasis of hepatocellular carcinoma (HCC). However, the molecular mechanisms behind this relationship are not fully understood. In our study, we utilized long‐noncoding RNA (lncRNA) microarrays to identify a HNRNPAB‐regulated lncRNA named lnc‐ELF209. Our findings from chromatin immunoprecipitation assays indicate that HNRNPAB represses lnc‐ELF209 transcription by directly binding to its promoter region. We also analyzed clinical samples from HCC patients and cell lines with quantitative real‐time polymerase chain reactions, RNA in situ hybridization and immunohistochemistry, and found that there is a negative relationship between HNRNPAB and lnc‐ELF209 expression. Up/downregulation assays and rescue assays indicate that lnc‐ELF209 inhibits cell migration, invasion and epithelial–mesenchymal transition regulated by HNRNPAB. This suggests a new regulatory mechanism for HNRNPAB‐promoted HCC progression. RNA pull‐down and LC–MS/MS were used to determine triosephosphate isomerase, heat shock protein 90‐beta and vimentin may be involved in the tumor‐suppressed function of lnc‐ELF209. Furthermore, we found lnc‐ELF209 could stabilize TPI protein expression. We also found that lnc‐ELF209 overexpression in HCCLM3 cell resulted in a lower rate of lung metastatic, which suggested a less aggressive HCC phenotype. Collectively, these findings offer new insights into the regulatory mechanisms that underlie HNRNPAB cancer‐promoting activities and demonstrate that lnc‐ELF209 is a HNRNPAB‐regulated lncRNA that may play an important role in the inhibition of HCC progression.
Customer concentration, institutions, and corporate bond contracts
Authors: Liu Chenyan , Xiao Zuoping , Xie Hong
Published: May 2019

We examine the effect of customer concentration, the quality of institutions, and their interaction on corporate bond contract terms in China. We find that higher customer concentration is associated with higher bond spreads, shorter bond maturity, and more bond covenants. In contrast, better institutions are associated with lower bond spreads, longer bond maturity, and fewer bond covenants. Moreover, we find that the adverse or unfavourable association between customer concentration and bond contract terms is weakened for firms operating within better institutions or for firms whose ultimate owners are the Central Government of China. Furthermore, the adverse association between customer concentration and bond contract terms is more pronounced when a supplier's major customers have lower switching costs or when the supplier has made more relationship‐specific investments. Finally, our main results are robust to controls for endogeneity concerns and other sensitivity checks. Overall, our findings suggest that bondholders view customer concentration as a risk factor but better institutions as a protection.
A rapid knowledge‐based partial supervision fuzzy c‐means for brain tissue segmentation with CUDA‐enabled GPU machine
Authors: Sriramakrishnan Padmanaban , Kalaiselvi Thiruvenkadam , Somasundaram Karuppanagounder , Rajeswaran Rangasami
Published: May 2019

The proposed work aims to quicken the magnetic resonance imaging (MRI) brain tissue segmentation process using knowledge‐based partial supervision fuzzy c‐means (KPSFCM) with graphics processing unit (GPU). The proposed KPSFCM contains three steps: knowledge‐based initialization, modification, and optimization. The knowledge‐based initialization step extracts initial centers from input MR images for KPSFCM using Gaussian‐based histogram smoothing. The modification step changes the membership function of PSFCM, which is guided by the labeled patterns of cerebrospinal fluid portion. Finally, the optimization step is achieved through size‐based optimization (SBO), adjacency‐based optimization (ABO), and parallelism‐based optimization (PBO). SBO and ABO are algorithmic level optimization techniques in central processing unit (CPU), whereas PBO is a hardware level optimization technique implemented in GPU using compute unified device architecture (CUDA). Performance of the KPSFCM is tested with online and clinical datasets. The proposed KPSFCM gives better segmentation accuracy than 14 state‐of‐the‐art‐methods, but computationally expensive. When the optimization techniques (SBO and ABO) were included, the execution time reduces by 13 times in CPU. Finally, the inclusion of PBO yields 19 times faster than the optimized CPU implementation.
Pharmacokinetic Analysis and Biomarker‐Assisted Safety Assessment of Acetaminophen in Combination With Ojeok‐san Compared With Acetaminophen Alone
Authors: Park Sang‐In , Park Ji‐Young , Lee Ji Hyun , Park Mun Su , Lee Kyung‐Tae , Yim Sung‐Vin , Yoon Young‐Ran , Kim Bo‐Hyung
Published: May 2019

Acetaminophen and Ojeok‐san are both frequently used analgesics. In this study, we evaluated acetaminophen pharmacokinetics (PK) and changes in microRNA‐122 (miR‐122) levels after multiple dosing of acetaminophen with or without Ojeok‐san. An open‐label, 1‐sequence, 2‐period, 2‐treatment crossover study was conducted in 18 subjects. In period 1, 500 mg of acetaminophen was administered 3 times on day 1 and once on day 2. In period 2, after the administration of 14.47 g of Ojeok‐san twice on day 2 and 3 times daily on days 3 to 7, Ojeok‐san and acetaminophen were coadministered 3 times each on day 8 and once each on day 9. The geometric mean ratios (90% confidence intervals) of acetaminophen with Ojeok‐san to acetaminophen alone were 0.98 (0.87 to 1.10) and 1.02 (0.98 to 1.05) for the maximum plasma concentration (Cmax) and the area under the plasma concentration‐time curve during the dosing interval (AUC0‐τ), respectively, of acetaminophen at steady state. The alanine aminotransferase (ALT) levels were within the reference range in all the participants throughout the study period, although the mean fold changes in both serum miR‐122 and ALT levels from baseline tended to increase on days 2 to 5. In conclusion, the PK properties of acetaminophen were not significantly affected by Ojeok‐san coadministration. For osteoarthritis patients taking acetaminophen with or without Ojeok‐san, monitoring potential liver toxicity using miR‐122 as a biomarker may be useful.
Screening of heterogeneous catalysts for the activated persulfate oxidation of sulfamethoxazole in aqueous matrices. Does the matrix affect the selection of catalyst?
Authors: Ribeiro Rui S , Frontistis Zacharias , Mantzavinos Dionissios , T Silva Adrián M , Faria Joaquim L , Gomes Helder T
Published: May 2019

BACKGROUND

The contribution of persulfate oxidation to water treatment technologies based on advanced oxidation processes is nowadays widely accepted. However, the importance of the water matrix on the removal of micropollutants has been neglected during early screening of heterogeneous catalysts, which can hinder further developments in the field.

RESULTS

Three magnetic graphitic nanocomposites (MGNCs), obtained by carbon encapsulation of magnetite (Fe3O4), nickel ferrite (NiFe2O4) and cobalt ferrite (CoFe2O4), were prepared and employed as heterogeneous catalysts in the activation of persulfate for the degradation of antibiotic sulfamethoxazole (SMX). The importance of the water matrix and its constituents on the performance of the MGNC materials was assessed. It was found that their relative performance in terms of oxidation of SMX in pure water decreases in the order: NiFe2O4/MGNC > Fe3O4/MGNC > CoFe2O4/MGNC. However, the order changed (Fe3O4/MGNC > NiFe2O4/MGNC > CoFe2O4/MGNC) when drinking water or secondary treated wastewater were employed. The individual effects of the water matrix constituents, such as bicarbonate, chloride, pH, and humic acid, or the use of added radical scavengers, on the catalyst performance were investigated, while the heterogeneous nature of the process was confirmed through leaching tests.

CONCLUSION

A realistic water matrix should be considered throughout all the steps involved in the evaluation of new heterogeneous catalysts for the activated persulfate oxidation of SMX. Otherwise, misleading conclusions may be drawn, limiting potential improvements of this treatment technology. © 2019 Society of Chemical Industry
Contribution of IDO to human respiratory syncytial virus infection
Authors: Benavente Felipe M , Soto Jorge A , Pizarro-Ortega Magdalena S , Bohmwald Karen , González Pablo A , Bueno Susan M , Kalergis Alexis M
Published: May 2019

IDO is an enzyme that participates in the degradation of tryptophan (Trp), which is an essential amino acid necessary for vital cellular processes. The degradation of Trp and the metabolites generated by the enzymatic activity of IDO can have immunomodulating effects, notably over T cells, which are particularly sensitive to the absence of Trp and leads to the inhibition of T cell activation, cell death, and the suppression of T cell effector functions. Noteworthy, T cells participate in the cellular immune response against the human respiratory syncytial virus (hRSV) and are essential for viral clearance, as well as the total recovery of the host. Furthermore, inadequate or non-optimal polarization of T cells is often seen during the acute phase of the disease caused by this pathogen. Here, we discuss the capacity of hRSV to exploit the immunosuppressive features of IDO to reduce T cell function, thus acquiring relevant aspects during the biology of the virus. Additionally, we review studies on the influence of IDO over T cell activation and its relationship with hRSV infection.
Revisiting the role of calcium in phagosome formation and maturation
Authors: Westman Johannes , Grinstein Sergio , Maxson Michelle E
Published: May 2019

Like other membrane receptor-mediated responses, execution of phagocytosis requires the transduction of signals to cytoplasmic effectors. Signaling in this case is particularly complex as the process involves not only the formation of phagosomes but also their subsequent maturation and resolution. Transient increases in cytosolic calcium, which mediate a variety of other transduction pathways, also feature prominently in phagocytosis. However, despite intensive study over the course of nearly 30 years, the occurrence, source, and functional relevance of such calcium bursts remain the subject of debate. Here, we have attempted to consolidate the information that was reviewed in the past with more recent studies in an effort to shed some light on the existing controversies.
DOA estimation based on support vector machine ensemble
Authors: Sun Fei‐yan , Tian Yu‐bo , Hu Guo‐bing , Shen Qian‐yan
Published: May 2019

A synthesis model based on support vector machine ensemble (SVME) is proposed for the direction of arrival (DOA) estimation. This method is based on the advantages of the support vector machine (SVM), such as high fitting precision, simple structure, and strong generalization ability. The basic concept of the method is to select SVMs, optimally, to construct an SVME with the aid of the binary particle‐swarm optimization algorithm. The performance of the proposed model is validated by comparing its simulation results with that of neural networks and a few other state‐of‐the‐art models. Experiments show that this method can reduce the prediction error and improve the generalization ability, using a limited number of training samples.
Temperature‐dependent small signal performance of GaN‐on‐diamond HEMTs
Authors: Chen Yongbo , Xu Yuehang , Zhou Jianjun , Kong Yuechan , Chen Tangsheng , Zhang Yong , Yan Bo , Xu Ruimin
Published: May 2019

This paper presents the temperature dependence of small signal performance of GaN‐on‐diamond high electron mobility transistors (HEMTs) at an ambient temperature range from 0°C to 125°C. The temperature influence on the parasitic resistances together with the intrinsic parameters is investigated, and the temperature coefficients of these parameters are extracted from measured data. For comparison, a GaN‐on‐SiC device is also investigated. These results are important for the development and application of the GaN‐on‐diamond HEMT technology.
Permanent junctional reciprocating tachycardia in infants and Children
Authors: Kylat Ranjit I. , Samson Ricardo A.
Published: May 2019

Permanent junctional reciprocating tachycardia (PJRT) is a rare form of supraventricular tachycardia (SVT). It generally presents in infants but can be difficult to diagnose. The characteristic EKG findings, response to Adenosine and persistence or frequent recurrences are helpful in making the diagnosis. It is usually difficult to manage with the initial and single medications used in SVT. Many patients are misdiagnosed and not treated effectively and end up having end stage cardiomyopathy and are diagnosed in patients referred for transplant. Hence all patients referred for a cardiac transplant with dilated cardiomyopathy need to be evaluated for this arrhythmia. If appropriate treatment is started early in the course, the failure can be ameliorated, and the cardiomyopathy can be resolved.
Definition of hypertension‐associated oral pathogens in NHANES
Authors: Pietropaoli Davide , Del Pinto Rita , Ferri Claudio , Ortu Eleonora , Monaco Annalisa
Published: May 2019

Background

Increasing evidence links periodontal microbiota to several systemic conditions, including high blood pressure (BP). Antibodies to oral pathogens can be considered an indirect assessment of periodontal bacterial burden. We aimed at assessing the relationship between systemic exposure to periodontal microbiota, expressed in terms of relative antibodies, and BP, using data from the third National Health and Nutrition Examination Survey (NHANES III).

Methods

We analyzed cross‐sectional, nationally representative data from 7,928 adults aged ≥40 years who underwent determination of BP and serum antibodies to 21 periodontal microorganisms. BP was examined as both continuous (mmHg) and binary (≷130/80 mmHg, i.e. normal/controlled or high/uncontrolled BP) variables. Pearson and Spearman correlations restricted maximum likelihood, crude and adjusted generalized additive models, and a machine learning approach based on gradient boosting modeling were combined to verify any association between antibodies to periodontal microbiota and BP.

Results

Antibodies toCampylobacter rectus, Veillonella parvula, Prevotella melaninogenicawere consistently associated with high/uncontrolled BP by about +3 mmHg of systolic and +2 mmHg of diastolic BP and with 10% to 13% higher odds of high/uncontrolled BP, as well as with more active periodontal disease and greater changes in clinical parameters of periodontitis. Antibodies toC. rectusresulted in the strongest association with BP.

Conclusions

There is an association between systemic exposure to periodontal microbiota and BP. Understanding the pathogenetic mechanisms that shape such relationships, and the relative potential impact on personalized medicine, is the challenge of future research.
Formulation of Raman scattering revisited
Authors: Morita Reiko , Morita Hayato , Tasumi Mitsuo
Published: May 2019

In Raman scattering, photons are scattered by electrons in a molecule. Its mechanism was elucidated early after the development of quantum mechanics. If the frequencies of incident and scattered photons are denoted respectively by ν0 and νs, the differential scattering cross section of a Raman band is proportional to
. The differential scattering cross section of Rayleigh scattering is proportional to
, as is known as the ν4 rule. This article reconfirms these points from a tutorial viewpoint.
A Novel Ultrasound Technique Called Saline Infusion SonoPODography to Visualize and Understand the Pouch of Douglas and Posterior Compartment Contents: A Feasibility Study
Authors: Leonardi Mathew , Espada Mercedes , Lu Chuan , Stamatopoulos Nicole , Condous George
Published: May 2019

Women with infertility are often investigated with saline‐infusion sonohysterography and hysterosalpingo‐contrast‐sonography. The high prevalence of endometriosis in this population also warrants an evaluation with transvaginal ultrasound for deep endometriosis. To minimize investigations, we prospectively evaluated the feasibility of a novel combined ultrasound technique called saline‐infusion sonoPODography. In most patients, the fluid infused to assess the cavity and tubal patency spilled through patent tubes and filled the pouch of Douglas, yielding a “standoff” view of posterior compartment structures, including uterosacral ligaments, rectovaginal septum, and the pouch of Douglas. We believe this improved our ability to evaluate this space.
Does perioperative oxandrolone improve nutritional status in patients with cachexia related to head and neck carcinoma?
Authors: Osmolak Angela M. , Klatt‐Cromwell Cristine N. , Price Amber M. , Sanclement Jose A. , Krempl Greg A.
Published: May 2019

Background

Cancer cachexia affects up to over 50% of advanced head and neck cancer (HNC) patients. To date, the potential utility of anabolic steroids in perioperative cachectic HNC patients has not been determined.

Methods

Retrospective review of pre‐ and post‐oxandrolone administration prealbumin levels in 18 perioperative HNC patients between October 2007 and October 2014 at a tertiary academic medical center.

Results

The median pretreatment prealbumin was 88.5 mg/L. The median post‐treatment prealbumin was 227 mg/L. The median interval improvement of the prealbumin level was 131.5 mg/L. The median differences between the pretreatment and post‐treatment prealbumin levels were found to be statistically significant (P < .001). Subjective improvement in wound healing was also observed.

Conclusions

Perioperative administration of oxandrolone resulted in objective improvements in prealbumin levels and subjective improvements in surgical wounds. Oxandrolone administered 10 mg twice daily (BID) for 10 days may be a useful adjunct in the perioperative care of nutritionally deficient HNC patients who are at risk for or have demonstrated impaired wound healing.

Level of Evidence

3
The First In Vivo Needle‐Based Optical Coherence Tomography in Human Prostate: A Safety and Feasibility Study
Authors: Swaan Abel , Mannaerts Christophe K. , Muller Berrend G. , van Kollenburg Rob AA. , Lucas Marit , Savci‐Heijink C Dilara , van Leeuwen Ton G. , de Reijke Theo M. , de Bruin Daniel M.
Published: May 2019

Objective

To demonstrate the safety and feasibility of clinical in vivo needle‐based optical coherence tomography (OCT) imaging of the prostate.

Materials and Methods

Two patients with prostate cancer underwent each two percutaneous in vivo needle‐based OCT measurements before transperineal template mapping biopsy. The OCT probe was introduced via a needle and positioned under ultrasound guidance. To test the safety, adverse events were recorded during and after the procedure. To test the feasibility, OCT and US images were studied during and after the procedure. Corresponding regions for OCT and biopsy were determined. A uropathologist evaluated and annotated the histopathology. Three experts assessed all the corresponding OCT images. The OCT and biopsy conclusions for the corresponding regions were compared.

Results

No adverse events during and following the, in total four, in vivo needle‐based OCT measurements were reported. The OCT measurements showed images of prostatic tissue with a penetration depth of ~1.5 mm. The histological‐proven tissue types, which were also found in the overlapping OCT images, were benign glands, stroma, glandular atrophy, and adenocarcinoma (Gleason pattern 3).

Conclusions

Clinical in vivo needle‐based OCT of the prostate is feasible with no adverse events during measurements. OCT images displayed detailed prostatic tissue with a imaging depth up to ~1.5 mm.

We could co‐register four histological‐proven tissue types with OCT images. The feasibility of in vivo OCT in the prostate opens the pathway to the next phase of needle‐based OCT studies in the prostate. Lasers Surg. Med. 51:390–398, 2019. © 2019 The Authors. Lasers in Surgery and Medicine Published by Wiley Periodicals, Inc.
Morphology Evolutions and Mechanical Properties of In Situ Fibrillar Polylactic Acid/Thermoplastic Polyurethane Blends Fabricated by Fused Deposition Modeling
Authors: Wang Jianye , Zhang Yifan , Sun Wei , Chu Shaosheng , Chen Tao , Sun Aihua , Guo Jianjun , Xu Gaojie
Published: May 2019

There are many studies devoted to conquer the strength–ductility trade‐off dilemma of polylactic acid (PLA) by flexible elastomer blending, like thermoplastic polyurethane (TPU), but little is known about the effects of the fused deposition modeling (FDM) process on the in situ morphology evolution of the elastomers. In this work, the effects of the three successive drawing processes in FDM on the morphology evolution of the dispersed TPU in the PLA matrix, and the toughening behavior of FDM‐printed PLA/microfibrillar‐TPU blends, are systematically studied. The results manifest that the average length of the TPU microfibrils can be turned precisely from 67.24 to 103.72 µm. The in situ microfibrillation process can remarkably improve the PLA crystallization capability and interfacial interaction. More interestingly, the inevitable decrease of impact strength of FDM‐printed part induced by the voids is compensated by the network‐like TPU microfibrils formed during the layer‐by‐layer printing. These inspiring findings suggest that the in situ fibrillation process can conquer the inherent weaknesses of both FDM process and PLA materials, providing facile and efficient method for fabricating high toughness PLA parts.
Thermal Insulation Characteristics of Polybenzoxazine Aerogels
Authors: Xiao Yunyun , Li Liangjun , Zhang Sizhao , Feng Junzong , Jiang Yonggang , Feng Jian
Published: May 2019

Polybenzoxazine (PBO) aerogels with low densities and low thermal conductivities are prepared from Bisphenol A (BPA) benzoxazine monomers by ring‐opened polymerisation using HCl as a catalyser at 10 °C. The obtained PBO aerogels have cross‐linked and 3D network structures with the densities ranging from 0.084 to 0.526 g cm−3. The thermal conductivities under different pressures (3–105 Pa, air) and different atmospheres (N2, Ar, and CO2, 105 Pa) are investigated. The thermal conductivities are in the range of 0.0335–0.0652 W m K−1 under ambient pressure and 0.0098–0.0571 W m K−1 at 3 Pa. The thermal transfer mechanism under different gas pressures is analyzed with increasing pressure. Under different atmospheres, the thermal conductivities decrease as the molecular weight of the gas increases. Compared with the traditional organic foam insulating materials of phenolic foam, polyurethane and polystyrene, which have similar apparent densities, PBO aerogels exhibit lower thermal conductivity of 0.0335 W m K−1 than that of traditional organic foam at room temperature.
Lightweight, Elastomeric, and Flame‐Retardant Foams from Expanded Chlorinated Polymers
Authors: Zhang Zhen Xiu , Dai Xin‐ru , Luo Peng , Sinha Tridib K. , Kim Jin Kuk , Li Huan
Published: May 2019

Intrinsically flame‐retardant polymers based on lightweight and elastomeric microcellular foams are successfully prepared from flexible chlorinated polyethylene (CPE)/chlorinated polyvinylchloride (CPVC) compounds through compression molding foaming technology. The incorporation of CPVC to CPE at once improves the foam characteristics, and enhances the mechanical and fire performances. Due to the plausible intermolecular and intramolecular crosslinking among the polymer chains, the dense network structure of CPE/CPVC with enhanced strength results in increased cell size, reduced cell density, and improved dimensional stability of CPE/CPVC foams (CCFs). These improvements are noticed to be enhanced with increasing CPVC content in the CCF. Also, the flame‐retardant properties of the foams (i.e., limiting oxygen index and cone calorimeter combustion) are found to be increased with the increase of CPVC content. For instance, a highly flame‐retardant CCF at CPE/CPVC ratio of 60/40 shows a shorter combustion period, as derived from the respective heat release rate vs time curve. Corresponding peaks of heat release rate, total heat release rate, peak of mass loss rate, total smoke release, and char residue are recorded to be 8.4%, 5.8%, 3.0%, 6.6%, and 1000.1% of those recorded for the pristine CPE foam.
Cable‐Shaped Lithium–Sulfur Batteries Based on Nitrogen‐Doped Carbon/Carbon Nanotube Composite Yarns
Authors: Yuan Hongxin , Zhang Miao , Yang Chen , Liu Lixuan , Lu Ruichao , Mao Lijuan , Wei Zhixiang
Published: May 2019

The research on flexible and wearable devices has attracted extensive attention in the last few years. Lithium–sulfur (Li‐S) batteries are regarded as a promising option because of their high theoretical capacity and energy density. Here, cable‐shaped Li‐S batteries are developed based on a nitrogen‐doped carbon/carbon nanotube/sulfur (NCNT/S) composite cathode and lithium metal anode. The carbon nanotube (CNT) yarns with high conductivity and an appropriate amount of doped nitrogen are synthesized by wet‐spinning followed by a carbonization process, and further act as a self‐supported conductive backbone for the active material. The NCNT/S yarns exhibit a high initial capacitance of 1001 mAh g−1 and excellent cyclic stability with 87% capacity retention after 200 cycles at 0.5 C. Furthermore, the assembled cable‐shaped Li‐S batteries by NCNT/S yarns present good ability to light up the LEDs for more than 8 h under normal and bending states at various angles, indicating that the cable‐shaped Li‐S batteries could be a prospective candidate for application in wearable electronics.
Healthcare burden among individuals with Angelman syndrome: Findings from the Angelman Syndrome Natural History Study
Authors: Khan Nasreen , Cabo Raquel , Tan Wen‐Hann , Tayag Regina , Bird Lynne M.
Published: May 2019

Background

The objective of this study is to describe healthcare resource utilization (HRU) and supportive therapy utilization (STU) among individuals with Angelman syndrome (AS), and to compare such usage by molecular etiology.

Methods

Participants were categorized into deletion and non‐deletion genotypes. Statistical differences were assessed using an independent samples t test.

Results

Data were available on 302 individuals. Mean age of participants was 5.5 years, 92% of whom were less than 13 years, and 71% had the deletion etiology. About 68% of participants had at least one hospitalization since birth to enrollment in the study; the average number of hospitalizations during that time period was 2.3 and average length of stay was 4.5 days. The most common reasons for hospitalization were seizures, lower respiratory infections, and surgery. The most common reasons for surgery were myringotomy, strabismus surgery, tonsillectomy or adenoidectomy, and gastrostomy tube insertion/fundoplication. Anticonvulsants, gastroesophageal reflux disease, sleep, and behavioral medications were the most commonly prescribed drugs. STU was high among individuals with AS.

Conclusions

This study shows that individuals with AS have high HRU/STU, and apart from a few differences, HRU/STU was similar across molecular etiology. These results reflect usage in younger individuals and studies that describe HRU/STU in older individuals are needed.
MEIS1 knockdown may promote differentiation of esophageal squamous carcinoma cell line KYSE‐30
Authors: Mahmoudian Reihaneh Alsadat , Bahadori Bahareh , Rad Abolfazl , Abbaszadegan Mohammad Reza , Forghanifard Mohammad Mahdi
Published: May 2019

Background

MEIS1 (Myeloid ecotropic viral integration site 1), as a homeobox (HOX) transcription factor, has a dual function in different types of cancer. Although numerous roles are proposed for MEIS1 in differentiation, stem cell function, gastrointestinal development and tumorigenesis, the involved molecular mechanisms are poor understood. Our aim in this study was to elucidate the functional correlation between MEIS1, as regulator of differentiation process, and the involved genes in cell differentiation in human esophageal squamous carcinoma (ESC) cell line KYSE‐30.

Methods

The KYSE‐30 cells were transduced using recombinant retroviral particles containing specific shRNA sequence against MEIS1 to knockdown MEIS1 gene expression. Following RNA extraction and cDNA synthesis, mRNA expression of MEIS1 and the selected genes including TWIST1, EGF, CDX2, and KRT4 was examined using relative comparative real‐time PCR.

Results

Retroviral transduction caused a significant underexpression of MEIS1 in GFP‐hMEIS1 compared to control GFP cells approximately 5.5‐fold. While knockdown of MEIS1 expression caused a significant decrease in EGF and TWIST1 mRNA expression, nearly ‐8‐ and ‐12‐fold respectively, it caused a significant increase in mRNA expression of differentiation markers including KRT4 and CDX2, approximately 34‐ and 1.14‐fold, correspondingly.

Conclusion

MEIS1 gene silencing in KYSE‐30 cells increased expression of epithelial markers and decreased expression of epithelial‐mesenchymal transition (EMT) marker TWIST1. It may highlight the role of MEIS1 in differentiation process of KYSE‐30 cells. These results may confirm that MEIS1 silencing promotes differentiation and decreases EMT capability of ESC cell line KYSE‐30.
Solvability of eight classes of nonlinear systems of difference equations
Authors: Stević Stevo , Tollu Durhasan T.
Published: May 2019

We have studied recently solvability and semi‐cycles of eight systems of difference equations of the following form:

urn:x-wiley:mma:media:mma5625:mma5625-math-0001
where a ∈ [0, + ∞), the sequences pn, qn, rn, sn are some of the sequences xn and yn, with positive initial values x−j,y−j, j = 1,2, in detail. This paper is devoted to the study of the other eight systems of the form. We show that these systems are also solvable in closed form and describe semi‐cycles of their solutions complementing our previous results on such systems of difference equations.
Controllability of impulsive fractional functional evolution equations with infinite state‐dependent delay in Banach spaces
Authors: Aimene Djihad , Seba Djamila , Laoubi Karima
Published: May 2019

Many evolutionary processes from various fields of physical and engineering sciences undergo abrupt changes of state at certain moments of time between intervals of continuous evolution. These processes are more suitably modeled by impulsive differential equations. In this paper, we study the controllability of an impulsive fractional differential equation with infinite state‐dependent delay in an arbitrary Banach space. We apply semigroup theory and Schaefer fixed point theorem. As an application, we include an example to illustrate the theory.
Inverse spectral problem of fourth‐order boundary value problems with finite spectrum
Authors: Ao Ji‐Jun , Zhang Liang
Published: May 2019

In the present paper, we consider a class of inverse spectral problem of fourth‐order boundary value problems. Under the so‐called “Atkinson type” conditions, the problem has finite spectrum and corresponding matrix representations. By using the method of inverse matrix eigenvalue problems of two‐banded matrix, the leading coefficient and potential functions are reconstructed from the given three sets of interlacing real numbers satisfying certain conditions.
As a Histone Deacetylase Inhibitor, γ‐Aminobutyric Acid Upregulates GluR2 Expression: An In Vitro and In Vivo Study
Authors: Xing Aiping , Li Xinhui , Jiang Congmin , Chen Yanqiu , Wu Sining , Zhang Jingzhu , An Li
Published: May 2019

Scope

γ‐Aminobutyric acid (GABA) possesses extensive physiological functions and can be directly obtained from foods. GABA‐enriched functional foods have been developed and the commercial demands for GABA are increasing. GABA is widely recognized as a central nervous system inhibitory neurotransmitter and plays an important role in some diseases by binding to its receptors. However, some of the functions of GABA are not explained by neurotransmission or GABA receptor pathways. Therefore, this study investigates whether GABA has the potential to inhibit histone deacetylase (HDAC).

Methods and results

It is found that GABA inhibits HDAC1/2/3 expression and upregulates histone acetylation levels (Ace‐H3K9/Ace‐H4K12) in SH‐SY5Y cells (which express GABA receptors), 3T3‐L1 cells (which do not express GABA receptors), and the cerebral cortex in mice. Glutamate receptor 2 (GluR2) is a subunit of the α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazole propionate (AMPA) receptor and is implicated in the pathogenesis of some neurological diseases. It is also found that GABA increases GluR2 expression by inhibiting HDAC1/2 but not HDAC3.

Conclusion

A novel role for GABA is demonstrated in which it acts as an HDAC inhibitor. The present study expands the horizons for exploring the non‐neurotransmitter functions of GABA.
Small‐sized, decoupled two‐monopole antenna system using the same monopole as decoupling structure
Authors: Su Saou‐Wen , Hsiao Ya‐Wen
Published: May 2019

A simple decoupling technique utilizing the same radiator geometry as the resonator‐based decoupling structure for the isolation enhancement is proposed. The design consists of two identical radiating monopoles and the same radiator grounded between the two monopoles. The targeted design footprint of the two‐antenna system occupies a size of 5 mm × 40 mm (about 0.04λ × 0.32λ at 2.4 GHz) with a gap of 2 mm between the radiating and the decoupling monopoles. Each monopole shows a small size of 5 mm × 12 mm, comprising a simple 5‐GHz monopole, a chip inductor, and a tuning end portion, and is capable of operating in the range between 2.4 GHz (2400‐2484 MHz) and 5 GHz (5150‐5825 MHz) wireless local area network bands. In this design, the decoupling structure is obtained by duplicating the radiating monopole but grounding its feed port to the small antenna ground. By properly tuning the lengths of the end portions for the radiating and the decoupling monopoles, good isolation better than 15 dB between the antennas in 2.4 and 5 GHz bands can be attained.
Systematically engineered electrospun conduit based on PGA/collagen/bioglass nanocomposites: The evaluation of morphological, mechanical, and bio‐properties
Authors: Dehnavi Navid , Parivar Kazem , Goodarzi Vahabodin , Salimi Ali , Nourani Mohammad Reza
Published: May 2019

Peripheral nerve injury can considerably affect the daily life of affected people through reduced function and permanent deformation of the nerve. One of the conventional treatments used for the management of the disease is the application of autograft, which is recognized as a golden standard method; however, the process of gaining access to autograft has posed a significant challenge to its use. Nerve guidance channels (conduits), which are made in different methods, can act as an alternative therapy for patients that have undergone nerve injury; but, achieving these conduits has always been a major dilemma to be applied for patients with nerve injury. In this study, a novel conduit based on polymer blend nanocomposites of polyglycolic acid (PGA), collagen, and nanobioglass (NBG) were prepared by electrospinning technique and then compared with PGA/collagen and PGA conduits that were made in previous studies. Additionally, their various properties were characterized by scanning electron microscopy (SEM), X‐ray diffraction (XRD), contact angle, dynamic mechanical thermal analysis (DMTA), tensile strength, Fourier‐transform infrared (FTIR), and the porosity and degradation. The results showed that the mechanical, chemical, biocompatibility, and biodegradability properties of PGA/collagen/NBG conduits were more favorable in comparison with other materials. According to 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) assay and 4′,6‐diamidino‐2‐phenylindole (DAPI) staining technique, nanofibrous electrospun PGA/collagen/NBG conduits are more suitable for cell adhesion and proliferation in comparison with either PGA or PGA/collagen conduits and can have potential for nerve regeneration.
Design and preparation of poly(lactic acid) hydroxyapatite nanocomposites reinforced with phosphorus‐based organic additive: Thermal, combustion, and mechanical properties studies
Authors: Hajibeygi Mohsen , Shafiei‐Navid Saeid
Published: May 2019

A new phosphorus‐based organic additive (PDA) was designed and successfully synthesized using a three‐component reaction for improvement of the thermal and combustion resistance of polylactic acid (PLA). For compensate for mechanical properties of PLA, hydroxyapatite nanoparticles was modified via in situ surface modification with PDA and was used for preparation of PLA nanocomposites. The structure and morphology as well as thermal, combustion, and mechanical properties of the all PLA systems were investigated. The X‐ray diffraction (XRD) and field‐emission scanning electron microscopy (FE‐SEM) results indicated that the presence of PDA as surface modifier has been necessary for a desirable dispersion of hydroxyapatite (HA) nanoparticles in the PLA matrix. The thermal, combustion, and mechanical properties of the PLA system films were investigated using thermogravimetric analysis (TGA), microscale combustion calorimeter (MCC), and tensile test, respectively. The initial decomposition temperature and char residue of PLA containing 6 mass% of PDA along with 2 mass% HA nanoparticles were increased 20°C and 12% respectively, compared with that of the neat PLA. The peak of heat release rate was decreased from 566 W/g for the neat PLA to 412 W/g for PLA containing 2 mass% of PDA along with 6 mass% HA nanoparticles. By incorporation of only 2 mass% HA nanoparticles and 6 mass% of PDA, the tensile strength was obtained 51 MPa higher than that of the neat PLA.
Annealing Kinetics of the Interstitial Carbon–Dioxygen Complex in Silicon
Authors: Ayedh Hussein M. , Grigorev Aleksei A. , Galeckas Augustinas , Svensson Bengt G. , Monakhov Edouard V.
Published: May 2019

The interstitial carbon‐interstitial dioxygen complex (CiO2i) has a deep state close to the mid bandgap of Si and can be an efficient recombination center. In this work, the annealing kinetics of CiO2i in p‐type, boron doped, Czochralski grown (Cz) silicon are studied. Two sets of samples are irradiated at room temperature (RT) with 1.8 MeV protons to doses of 1 × 1013 cm−2 (set A) and 5 × 1013 cm−2 (set B). After irradiation, the samples of both sets are pre‐annealed at 400 °C for 30 h in order to anneal out the well‐known interstitial carbon‐interstitial oxygen (CiOi) complex and to form the CiO2i complex. The annealing of CiOi and formation of CiO2i is monitored by deep level transient spectroscopy (DLTS) via observation of the corresponding electronic levels at 0.36 eV and 0.39 eV above the valence band edge (EV), respectively. The samples are then subjected to isothermal annealing treatments in the temperature range 450–550 °C. The annealing of CiO2i follows a first order kinetics, exhibiting an activation energy of 2.55 eV, and a pre‐exponential factor in the range (2–30) × 1012 s−1. The kinetics and the deduced parameters suggest that CiO2i anneals out by dissociation rather than diffusion mechanism.
The Magnetocaloric Composite Designed by Multi‐Gd‐Al‐Co Microwires with Close Performances
Authors: Shen Hongxian , Luo Lin , Xing Dawei , Jiang Sida , Liu Jingshun , Huang Yongjiang , Guo Shu , Sun Haichao , Liu Yanfen , Sun Jianfei , Phan Manh‐Huong
Published: May 2019

A new magnetocaloric composite composed of three types of soft ferromagnetic Gd‐based microwires with equal mass ratio and close magnetocaloric performances is designed. The Curie temperatures (TC) of these three wires are ≈97, ≈100, and ≈101 K, respectively. However, the magnetization versus temperature curve of the composite sample shows almost a single ferromagnetic–paramagnetic transition at ≈97 K. For a field change of µ0ΔH = 5 T, the maximum entropy change () and refrigerant capacity (RC) of this composite are calculated to be ≈9.98 J kg−1 K−1 and ≈665 J kg−1, respectively. There is a good agreement between the calculated −ΔSM (T) curve and the experimental data, indicating weak magnetic interactions among different wire compositions. Additionally, the calculated universal master curves of the composite and its Gd‐Al‐Co components are fitted very well, which reveals the second‐order type of the magnetic transition for the composite. The designed composite integrates all magnetocaloric properties of its components, suggesting that the Gd‐based amorphous wires with close magnetocaloric properties can be designed as an excellent refrigerant for use in active magnetic refrigerators.
Non‐Bragg Bands in Acoustic Quasi‐Periodic Fibonacci Waveguides
Authors: Ma Bo-Yang , Liu Ting , Liu Wen-Bei , Xue Jiu-Ling , Tao Zhi-Yong
Published: May 2019

In this Letter, an algebraic topology analysis on the bandgaps in phononic Fibonacci waveguides consisting of wide and narrow stainless steel pipes is presented. It has been found that the non‐Bragg forbidden gaps can also exist in quasi‐periodic waveguide structures based on the constructed relations between the quasi‐periodic and periodic waveguides. The so‐called non‐Bragg gaps are caused by the resonances between different transverse modes while the same modes with matching longitudinal wavenumbers always result in the traditional Bragg gaps. In the experiments in this study, the observed non‐Bragg gap appears earlier than the Bragg one in the previous generations of Fibonacci sequences, and the sound attenuation is much more intense, because the lower generations with shorter lengths can only provide enough interaction effects in the transverse dimension. The algebraic topology methods and the observations of non‐Bragg gaps in quasi‐periodic waveguides can not only enrich the knowledge on wave structure interactions but also benefit various applications in wave control engineering.