bluuebunny/crossref_metadata_2025 huggingface dataset:
Asymptomatic radiographic sinonasal inflammation does not affect pituitary surgery outcomes
Authors: Kuan Edward C. , Rereddy Shruthi K. , Patel Neil N. , Maina Ivy W. , Triantafillou Vasiliki , Kohanski Michael A. , Tong Charles C.L. , Nabavizadeh Seyed A. , Lee John Y.K. , Grady M. Sean , O'Malley Bert W. , Palmer James N. , Adappa Nithin D.
Published: March 2019

Objective

Chronic rhinosinusitis (CRS) is a proposed risk factor for meningitis and other intracranial complications following the endoscopic endonasal transsphenoidal approach (TSA). Some have recommended staging TSA following surgery for CRS; however, delaying TSA has important ramifications. The objective of this study is to determine whether asymptomatic sinonasal inflammation (RSNI) on preoperative computed tomography scans, without clinical CRS, is associated with postoperative complications following TSA.

Methods

All consecutive TSA cases performed at a single tertiary care institution from January 1, 2009, to December 31, 2017, were reviewed for patient demographics, prior surgery, presence of RSNI on preoperative computed tomography scan based on Lund‐Mackay (LM) score, intraoperative cerebrospinal fluid (CSF) leak, and postoperative complications (postoperative CSF leak, bleeding, infection). The association between preoperative RSNI and postoperative complications was analyzed via multivariate logistic regression.

Results

One hundred seventy‐one cases of TSA were included with mean patient age of 52.6 years, 42.7% males, 18.1% revision cases, and mean LM score of 1.9 ± 2.7. Complications were identified in 9.9% of patients at the following rates: 5.3% postoperative CSF leak, 2.9% bleeding, and 1.8% infection (all sinusitis, no episodes of meningitis). Neither total LM score nor LM score > 5 (representative of clinically significant radiographic CRS) were predictors of any postoperative complication (both P > 0.05). Age, sex, revision status, intraoperative CSF leak, and total LM score were not independent predictors of any postoperative complication on multivariate analysis (all P > 0.05).

Conclusion

In asymptomatic patients, radiographic evidence of sinonasal inflammation is not associated with increased risk of complications following TSA.

Level of Evidence

4

Laryngoscope, 129:1545–1548, 2019
Surgical Outcomes in Idiopathic Recurrent Facial Nerve Paralysis: A Rare Clinical Entity
Authors: Sullivan Christopher Blake , Sun Daniel Q. , Zhu Vivian L. , Hansen Marlan R. , Gantz Bruce J.
Published: March 2019

Objective

To evaluate the postoperative facial nerve dysfunction, audiometric outcomes, and long‐term quality‐of‐life outcomes of patients with idiopathic recurrent facial nerve paralysis (RFP) after middle cranial fossa (MCF) microsurgical decompression.

Methods

Retrospective chart analysis of 11 (mean age 37.0 years, range 5 to 67) patients at an academic tertiary referral center who underwent MCF facial nerve decompression. Data analysis included evaluation of pre‐ and postoperative House‐Brackmann (HB) score, pre‐ and postoperative pure‐tone average (PTA), pre‐and postoperative word recognition scores (WRS), and postoperative Facial Clinimetric Evaluation survey.

Results

Mean number of preoperative facial paralysis episodes was 3.5 (range 2 to 6), and preoperative HB score was 4.5 (range 1 to 6). Postoperatively, 0 patients had further episodes of facial nerve paralysis at an average of 6.5 years (range 0.1 to 17.6) (P = 0.005), and the average postoperative HB score was 2.1 (range 1 to 3) (P = 0.011). Postoperative audiometry was stably maintained as assessed with PTA and WRS scores.

Conclusion

Microsurgical facial nerve decompression for idiopathic RFP may be a reliable therapeutic modality to prophylactically decrease the number of facial nerve paralysis episodes and may also help to improve facial nerve functional status.

Level of Evidence

4 Laryngoscope, 130:200–205, 2020
pH‐Responsive Polymer Nanoparticles for Drug Delivery
Authors: Deirram Nayeleh , Zhang Changhe , Kermaniyan Sarah S. , Johnston Angus P. R. , Such Georgina K.
Published: March 2019

Stimuli‐responsive nanoparticles have the potential to improve the delivery of therapeutics to a specific cell or region within the body. There are many stimuli that have shown potential for specific release of cargo, including variation of pH, redox potential, or the presence of enzymes. pH variation has generated significant interest for the synthesis of stimuli‐responsive nanoparticles because nanoparticles are internalized into cells via vesicles that are acidified. Additionally, the tumor microenvironment is known to have a lower pH than the surrounding tissue. In this review, different strategies to design pH‐responsive nanoparticles are discussed, focusing on the use of charge‐shifting polymers, acid labile linkages, and crosslinking.
SEM study of simulated clinical use for four nickel–titanium rotary endodontic files
Authors: Burke Jr. Thomas , Nusstein John , Drum Melissa , Fowler Sara , Brantley William A. , Draper John
Published: March 2019

Nickel–titanium (NiTi) rotary endodontic instruments are the major medical devices currently used for root canal therapy. Recently marketed NiTi files are manufactured using thermomechanical processes that improve fatigue resistance and flexibility, which are critical for clinical performance. This study employed a simulated clinical model to compare the wear and fracture of three such rotary instrument products (ProFile Vortex Blue™, ProTaper Gold™ and Coltene HyFlex® CM™), with a previously introduced product (ProFile Vortex™) serving as a control. Files were examined by scanning electron microscope (SEM) at four positions along their length before use and through three simulated clinical procedures on extracted teeth. Wear and deformation were evaluated by two experienced clinicians. Files were categorized as usable, visually unacceptable and microscopically unacceptable, and results were analysed statistically. Three files fractured, and nine files plastically deformed. Many unused instruments were judged to be microscopically unacceptable. There were no significant effects for brand and amount of use for files remaining visibly useful. Microscopically useful instruments were significantly affected by the number of uses. It was concluded that no observed wear or distortion pattern limited multiple file uses and that poorly manufactured surface condition was not necessarily a precursor to failure. Controlled‐memory instruments tended to deform plastically and present minimal fracture risk.
Admissible meromorphic solutions of algebraic differential‐difference equations
Authors: Wang Qiong‐Yan
Published: March 2019

By using Nevanlinna theory, we generalize a result given by Wittich to complex differential‐difference equations. The result obtained is that the differential‐difference equation in f which is of only one dominant term, has no admissible meromorphic solution f with hyper‐order less than 1 provided N(r,f) = S(r,f).
Efficient time‐domain numerical analysis of waveguides with tailored wideband pulses
Authors: Viquerat Jonathan
Published: March 2019

A simple procedure for the generation of accurate polychromatic sources in waveguides taking into account mode dispersion is presented. It allows for an efficient use of time‐domain solvers in the analysis of guided modes, and can be used whether the mode dispersion and field distribution are known analytically or numerically. This method is implemented in the Diogenes discontinuous Galerkin time‐domain (DGTD) solver (http://diogenes.inria.fr), and is validated on a waveguide mode converter.
Size Selectivity of Sampling Gears Used to Sample Kokanee
Authors: Klein Zachary B. , Quist Michael C. , Dux Andrew M. , Corsi Matthew P.
Published: March 2019

Kokanee Oncorhynchus nerka provide valued recreational fisheries and also serve as a prey resource for economically, socially, and ecologically important fishes. As such, management of kokanee is a major focus of natural resource agencies. Kokanee are typically monitored using midwater trawls, but the interpretation of data collected using midwater trawls is difficult due to the unknown size selectivity of the gear. We sought to assess the length selectivity of midwater trawls by comparing estimates obtained from midwater trawls with estimates obtained from gill nets adjusted for size selectivity. Experimental curtain gill nets and midwater trawls were used in conjunction to sample kokanee in seven lentic systems in Idaho. The size selectivity of gill nets was estimated by accounting for the probability of encounter and the probability of retention. Estimates of size selectivity were then used to adjust the length distribution of fish sampled in gill nets. The adjusted length distribution of fish sampled in gill nets was compared with estimates obtained from midwater trawls to identify potential size selectivity of midwater trawls. A pattern of size selectivity was apparent for both sampling techniques. The average length of kokanee sampled with midwater trawls was 111 mm; whereas, kokanee sampled with gill nets had a mean length of 235 mm. Our results suggest experimental gill nets are useful for common sampling of kokanee (e.g., trend monitoring) because the gear is less size selective than midwater trawls and is adjustable for size selectivity. However, midwater trawls are likely the best gear for addressing questions associated with early life history. Overall, our results provide a better understanding of gill-net and midwater trawl selectivity and ultimately improve the ability to sample and manage the species.
Experimentally Reducing Competition and Other Biotic Limitations Can Impact Growth, Food Habits, and Activity and Lead to Age-1 Maturation in Yellow Perch
Authors: Munter R. A. , Schoenebeck C. W. , Koupal K. D.
Published: March 2019

Much attention has been given to describing how abiotic factors impact the population dynamics of Yellow Perch Perca flavescens, especially during early life history; however, the impacts of biotic factors are less understood. In this study, we simplified the community assemblage to reduce interspecific competition and gain a better understanding of the role biotic conditions play in creating Yellow Perch fisheries. Yellow Perch were introduced into three recently renovated lakes in an attempt to increase growth rates through reduced interspecific competition and hypothetically allow fish to reach an acceptable size for angler harvest in a shorter period of time compared with four mixed-species lakes. Yellow Perch-only populations exhibited faster growth, potentially resulting from reduced interspecific competition, increased piscivory, and lower levels of activity. Yellow Perch-only populations also had more consistent recruitment, onset of maturation at age 1, and an earlier onset of sexual size dimorphism compared with mixed-species lakes and published literature. While limitations of density dependence were noted, natural resource managers are encouraged to investigate methods that would capitalize on the improved population dynamics of Yellow Perch-only lakes and the release from biotic controls.
Gill-Net Fishing Effort Predicts Physical Injuries on Sockeye Salmon Captured near Spawning Grounds
Authors: Kanigan Adam M. , Hinch Scott G. , Bass Arthur L. , Harrower William L.
Published: March 2019

Nonretention in gill-net fisheries for Pacific salmon Oncorhynchus spp. can be relatively high and can cause a variety of impairments to nonretained fish, which often lead to immediate or delayed mortality. We sought to improve the understanding of the association between gill-net escapement and injuries incurred by upriver-migrating salmon by examining the relationship between gill-net fishing effort in the Fraser River, British Columbia, and the frequency and severity of gill-net injuries to migrating Sockeye Salmon Oncorhynchus nerka. Adult Sockeye Salmon were intercepted at a location approximately 335 km from the mouth of the Fraser River and assessed for gill-net injuries. Gill-net fisheries targeting Sockeye Salmon operated throughout the first 320 km of the Fraser River main stem starting at the mouth of the river. A generalized linear mixed model was used to identify the role of gill-net fishing effort, fork length, and sex on the probability of an individual fish sustaining a gill-net injury. Predicted probabilities of gill-net injury ranged from 12% to 46% across all levels of fishing effort, suggesting that gill-net injuries were more prevalent among individuals that encountered high levels of fishing effort. However, fishing effort did not seem to influence the severity of gill-net injuries. Our results suggest that estimates of fishing effort may be useful in predicting the probability of gill-net injury to migrating fish, which could help managers estimate en route mortality and more accurately predict spawner escapement.
An upwind center difference parallel method and numerical analysis for the displacement problem with moving boundary
Authors: Li Changfeng , Yuan Yirang
Published: March 2019

A nonlinear coupled mathematical system of two‐phase seepage flow displacement is discussed in this paper including an elliptic equation for the pressure and a convection‐dominated diffusion equation for the saturation. In fact, the boundary of an underground region where the fluid flows through is nonstationary. So a moving boundary should be considered. The saturation equation is convection‐dominated, therefore the method of upwind finite difference is introduced for the accurate computation. The upwind approximation could eliminate numerical oscillation and strong stability is shown. Since the computational work of saturation is larger than the pressure, the authors apply a parallel method, decomposing the whole domain into several nonoverlapping subdomains, to simplify the computation. A domain decomposition method coupled with upwind differences is presented for the saturation. The pressure equation is discretized by a five‐point center finite difference method. By using a transformation and defining new inner products and norms, error estimates in l2 norm is discussed. Finally, two experimental tests are given to illustrate the efficiency and accuracy of the parallel algorithm.
A Rational Approach to Tetra‐Functional Photo‐Switches
Authors: Niermeier Philipp , Lamm Jan‐Hendrik , Mix Andreas , Neumann Beate , Stammler Hans‐Georg , Mitzel Norbert W.
Published: March 2019

α,ω‐Bis(1,8‐dichloroanthracen‐10‐yl)alkanes with (CH2)n‐linker units (n=1–4) were synthesized starting from 1,8‐dichloroanthracen‐10(9H)‐one. This was transformed into anthracenes with allyl, bromomethyl and propargyl substituents in position 10; these were converted in various C−C‐bond formation reactions (plus hydrogenation), leading to two anthracene units flexibly linked by α,ω‐alkandiyl groups. 1,2‐Ethandiyl‐ and 1,3‐propandiyl‐linked derivatives were functionalized with ethynyl groups in positions 1, 8, 1’ and 8’, and these terminally functionalized by Me3Sn groups using Me2NSnMe3. All linked bisanthracenes were subjected to UV light induced cyclomerization and a series of 9,10 : 9’,10’‐photo‐cyclomers were obtained. Their thermal cycloreversion and (repeated) switchability was demonstrated. 1,3‐Bis{1,8‐bis[(trimethylstannyl)ethynyl]anthracen‐10‐yl}propane served as model compound for photo‐switchable acceptor molecules and its open and closed forms were characterized by NMR and DOSY experiments.
Why is pancreatic cancer so deadly? The pathologist's view
Authors: Hruban Ralph H , Gaida Matthias M , Thompson Elizabeth , Hong Seung‐Mo , Noë Michaël , Brosens Lodewijk AA , Jongepier Martine , Offerhaus G Johan A , Wood Laura D
Published: March 2019

The remarkable aggressiveness of pancreatic cancer has never been fully explained. Although clearly multifactorial, we postulate that venous invasion, a finding seen in most pancreatic cancers but not in most cancers of other organs, may be a significant, underappreciated contributor to the aggressiveness of this disease. Copyright © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Sense of school belonging: Psychometric properties and differences across gender, grades, and East Asian societies
Authors: Kuang Xiaoxue , Mok Magdalena Mo Ching , Chiu Ming Ming , Zhu Jinxin
Published: March 2019

As students’ sense of school belonging (SOSB) is essential for their psychosocial well‐being and academic success, developing precise measures of SOSB is critical for assessing it properly. After an unrelated item was deleted, the SOSB scale showed good psychometric properties, based on Rasch analysis of data from 36,963 students in Grade 4 or Grade 8 from four East Asian societies. While no items showed gender differential item functioning (DIF), two items showed substantial society DIF, and two items showed grade DIF in Japan and South Korea. Concurrent equating created a common measurement scale for the four societies for future comparisons. The multigroup random slope two‐level analysis of the concurrent SOSB measures showed that SOSB is higher among girls than boys. From Grade 4 to Grade 8, SOSBs dropped substantially, especially for South Korea, and gender gaps decreased in Hong Kong, Japan, and South Korea. Hence, studies of interventions to improve SOSB, especially for boys and students in later grades, are vital.
Population‐based estimate of the use of intermittent androgen deprivation therapy in prostate cancer patients in Catalonia, Spain
Authors: Cordero José A. , Sancho Gemma , Bonfill Xavier
Published: March 2019

Purpose

To estimate the use of intermittent androgen deprivation (IAD) therapy in patients with prostate cancer (PCa).

Methods

Retrospective, non‐interventional study based on electronic pharmacy dispensation data of luteinizing hormone‐releasing hormone (LHRH) analogs and anti‐androgens in Catalonia (Spain). Intermittency was defined as the percentage of time off treatment (%IAD), which was calculated for the whole sample by dividing the sum of all off‐IAD periods by the total time on any LHRH analog regimen. The prevalence of patients on an IAD regimen (PIAD) was also estimated. A small validation study based on data from clinical records confirmed the excellent sensitivity and specificity of this approach.

Results

A total of 515 803 prescriptions for LHRH analog were dispensed over a 5‐year period (2008 to 2012) to 35 089 PCa patients. The mean age (±SD) was 77 years (±9). The %IAD in the cohort was 1.7% whereas the 5‐year prevalence (PIAD) was 4.2%. Only 2.5% of patients on IAD were on IAD for >6 months. Of the physicians (n = 1638) who prescribed hormonal treatment, 24% used IAD at least once. Total expenditures for LHRH analogs were 1.2% of total drug expenditure in this population.

Conclusions

This study confirms the validity of the method developed to estimate IAD use based on electronic pharmacy dispensation data. Given the large potential clinical and economic benefits that greater use of IAD could provide, future studies are needed to confirm these findings and to identify new strategies to increase the use of IAD.
Semiconductor–Metal Transition in Poly(3,4‐Ethylenedioxythiophene): Poly(Styrenesulfonate) and its Electrical Conductivity While Being Stretched
Authors: Paziresh Neda , Sotzing Gregory Allen
Published: March 2019

Poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) film was prepared from an aqueous dispersion of the polymer treated with 5 wt% dimethylsulfoxide (DMSO) on a glass substrate and was electronically characterized in order to study its electronic properties. The electrical resistance of the polymer film was measured over the temperature range (380–10 K) using four‐point probe technique. It was noticed that the electrical resistance followed three different trends each of which was indicative of a different charge carrier transport mechanism. Each mechanism was investigated in more detail. A semiconductor to metal transition was also observed at 292 K above which dR/dT had a positive slope. Furthermore, Hall effect, electrical conductivity and sheet resistance measurements were performed on the polymer film using van der Pauw technique. The metallic behavior of PEDOT:PSS at room temperature was further evidenced by the results of these measurements. Next, stretchable knitted fabric was coated with PEDOT:PSS prepared from the polymer dispersion treated with 5 wt% DMSO. The conductive fabric was then stretched axially to different amounts of strain and was electrically characterized in both relaxed and stretched states. Despite the constant decrease in its electrical conductivity, the fabric remained electrically conductive while being stretched under increasing applied strain. POLYM. ENG. SCI., 59:1051–1056, 2019. © 2019 Society of Plastics Engineers
Preparation and properties of modified graphene oxide incorporated waterborne polyurethane acrylate
Authors: Li Jing , Yin Yuhua , Muhammad Yaseen , Yang Jing , Yang Song , Yang Hongquan , Sahibzada Maria
Published: March 2019

In this study, a new modifier (KPG) was prepared by modifying graphene oxide with γ‐glycidoxypropyl trimethoxysilane (KH560) and polydimethylsiloxane (PDMS). KPG was in turn added to aqueous urethane acrylate for the fabrication of waterborne polyurethane polyacrylate emulsion modified with KH560‐PDMS composite (KPG/WPUA). Textural characterizations of the KPG/WPUA coating were achieved via Fourier transform infrared, SEM, TGA and AFM techniques, which revealed that the KPG/WPUA film possessed a smooth surface. The synthesized KPG/WPUA films were tested for mechanical properties, hydrophobicity and acid/water corrosion performance which suggested their highly hydrophobic surface. KPG/WPUA with 0.1% KPG showed a contact angle of 118.35°, 30.35° higher than that of pristine WPUA. The KPG/WPUA film exhibited higher thermal stability, i.e. a 5% weight loss temperature of 305 °C, which was 30 °C higher than that of pristine WPUA film. The Young's modulus and elongation at break of the KPG/WPUA film were 34.1 MPa and 74.88% respectively, which were higher than that of WPUA film. Furthermore, KPG/WPUA films exhibited greater resistance (without obvious blistering and the white spotting phenomenon) to H2O2, HCl and water corrosion than pristine WPUA. The superior performance of KPG/WPUA films was attributed to the network chain structure formed upon the introduction of KPG into WPUA. The outstanding performance of KPG/WPUA films in terms of mechanical properties, thermal stability and high resistance to acidic and water corrosion makes them interesting alternative contenders for target applications. © 2019 Society of Chemical Industry
In search for a hydride‐carbene bond
Authors: Jabłoński Mirosław
Published: March 2019

By presenting a large group of dimers featuring hydride‐carbene bond between silane and various carbenes, we show that electrophilic properties of singlet carbenes can manifest also to a hydridic, ie, negatively charged, hydrogen atom of a hydride. This type of interaction is traced by the corresponding bond path in 18 cases. However, taking into account the fact that in the case of large interatomic distances, the electrostatic potential maps are better indicators of dominant intermolecular interactions, it is shown that the amount of dimers with the hydride‐carbene bond is even larger, as indicated by both the proximity and correct orientation of theπ‐hole on the carbene carbon atom and the negative surface of the hydridic hydrogen of the silane molecule. The hydride‐carbene bond is weak, especially when compared with the hydride‐triel bond also involving the silane. In contrast to the latter, the intermolecular charge transfer is negligible. Moreover, the local electrostatic interaction involving the carbene carbon'sπ‐hole is not necessarily predominant in stabilization of all the carbene⋯silane complexes.
Lung ultrasound for prediction of respiratory support in infants with acute bronchiolitis: A cohort study
Authors: Bueno‐Campaña Mercedes , Sainz Talía , Alba Maria , del Rosal Teresa , Mendez‐Echevarría Ana , Echevarria Regina , Tagarro Alfredo , Ruperez‐Lucas Marta , Herrreros Maria L. , Latorre Libertad , Calvo Cristina
Published: March 2019

Objective

Respiratory tract infections are among the most common causes of morbidity and mortality worldwide. Acute bronchiolitis (AB) is the leading cause of hospital admission among infants. Clinical scores have proven to be inaccurate in predicting prognosis. Our aim was to build a score based on findings of lung ultrasound (LU) performed at admission, to stratify patients at risk of needing respiratory support (non‐invasive and invasive ventilation).

Study design

Prospective, multicenter study including infants <6 months of age admitted with AB. Point‐of‐care LU was performed on admission, and a score was calculated based on ultrasound findings (presence and localization of B lines, B line confluence and/or consolidations) and clinical data. Main outcome was need of respiratory support.

Results

A total of 145 patients were included in the study, with a median age of 1.7 months [IQR: 1.2‐2.8], 47.6% were female. Mean duration of symptoms prior to admission was 3.1 days (SD 1.8). Fifty‐six patients (39%) required non‐invasive ventilation (NIV), 14 (9.7%) were transferred to PICU, and 3 needed invasive ventilation (3/145). Identification of at least one posterior consolidation >1 cm was the main factor associated to NIV (RR 4.4; [CI95%1.8‐10.8]) The LU score built according to the findings on admission showed an AUC: 0.845(CI95%:0.78‐0.91). A score ≥3.5 showed a sensitivity of 89.1% (CI95%:78.2‐94.9%) and specificity of 56% (CI95%: 45.3‐66.1%)

Conclusions

Among infants below 6 months of age admitted with AB, point‐of‐care LU was a helpful tool to identify patients at risk of needing respiratory support.
Structural and functional characterization of a novel acidophilic 7α‐hydroxysteroid dehydrogenase
Authors: Tang Shijin , Pan Yinping , Lou Deshuai , Ji Shunlin , Zhu Liancai , Tan Jun , Qi Na , Yang Qiong , Zhang Zhi , Yang Biling , Zhao Wenyan , Wang Bochu
Published: March 2019

7α‐Hydroxysteroid dehydrogenase (7α‐HSDH) is an NAD(P)H‐dependent oxidoreductase belonging to the short‐chain dehydrogenases/reductases. In vitro, 7α‐HSDH is involved in the efficient biotransformation of taurochenodeoxycholic acid (TCDCA) to tauroursodeoxycholic acid (TUDCA). In this study, a gene encoding novel 7α‐HSDH (named as St‐2‐1) from fecal samples of black bear was cloned and heterologously expressed in Escherichia coli. The protein has subunits of 28.3 kDa and a native size of 56.6 kDa, which suggested a homodimer. We studied the relevant properties of the enzyme, including the optimum pH, optimum temperature, thermal stability, activators, and inhibitors. Interestingly, the data showed that St‐2‐1 differs from the 7α‐HSDHs reported in the literature, as it functions under acidic conditions. The enzyme displayed its optimal activity at pH 5.5 (TCDCA). The acidophilic nature of 7α‐HSDH expands its application environment and the natural enzyme bank of HSDHs, providing a promising candidate enzyme for the biosynthesis of TUDCA or other related chemical entities.
Resveratrol reduces the expression of insulin‐like growth factor‐1 and hepatocyte growth factor in stromal cells of women with endometriosis compared with nonendometriotic women
Authors: Arablou Tahereh , Delbandi Ali‐Akbar , Khodaverdi Sepideh , Arefi Soheila , Kolahdouz‐Mohammadi Roya , Heidari Sahel , Mohammadi Tahereh , Aryaeian Naheed
Published: March 2019

Resveratrol, a phytoalexin polyphenol, has antiproliferative, antiangiogenic, anti‐inflammatory, and antioxidant properties. The present study has assessed the effect of resveratrol treatment on the expression of insulin‐like growth factor‐1 (IGF‐1) and hepatocyte growth factor (HGF) in endometrial stromal cells (ESCs) from women with and without endometriosis. Endometrial tissues were obtained from 40 endometriotic patients and 15 nonendometriotic control women. After the enzymatic digestion, 13 eutopic ESCs (EuESCs), 8 ectopic ESCs (EESCs), and 11 control ESCs (CESCs) were treated with resveratrol (100 μM) for 6, 24, and 48 hr. The gene and protein expressions of IGF‐1 and HGF were measured using real‐time polymerase chain reaction and enzyme‐linked immunosorbent assay methods, respectively. Results showed that resveratrol treatment decreased significantly the gene expression of IGF‐1 and HGF in EuESCs, EESCs, and CESCs (p < 0.05). The effect of resveratrol treatment on the reduction of IGF‐1 gene expression was statistically more noticeable in EESCs compared with CESCs (p < 0.05). Also, in the case of HGF gene expression, the reducing effect of resveratrol treatment was statistically more considerable in EESCs compared with EuESCs and CESCs (p < 0.05 and p < 0.01, respectively). The IGF‐1 and HGF protein production decreased significantly in EuESCs and EESCs (p < 0.05) but not in CESCs. These findings suggest that resveratrol treatment could reduce the expression of IGF‐1 and HGF in ESCs especially in EESCs, which play a pivotal role in disease progression.
Retracted: Ganoderic acid A alleviates hypoxia‐induced apoptosis, autophagy, and inflammation in rat neural stem cells through the PI3K/AKT/mTOR pathways
Authors: Chang Yanhua , Kong Ruifang
Published: March 2019

Effects of ganoderic acid A (GAA), a lanostane triterpene, on hypoxia‐ischemia encephalopathy (HIE) remain unclear. We aimed to figure out the specific role of GAA in hypoxia‐treated neural stem cells (NSCs) as well as the regulatory mechanisms. Primary rat NSCs were incubated under hypoxia to simulate HIE. Viability and apoptosis of hypoxia‐injured NSCs were measured by cell counting kit‐8 and flow cytometry assays, respectively. Proteins related to apoptosis, autophagy, and the PI3K/AKT/mTOR pathways were evaluated by Western blot analysis. LY294002 and rapamycin were added to inhibit the PI3K/AKT pathway and mTOR pathway, respectively. Enzyme‐linked immunosorbent assay was carried out to test the release of proinflammatory cytokines. We found that hypoxia‐induced decrease of cell viability, increases of apoptotic cells and autophagy, and the release of IL‐6, IL‐1β, and TNF‐α were all attenuated by GAA stimulation. Activation of caspases induced by hypoxia was alleviated by GAA. Furthermore, we found that inhibition of the PI3K/AKT pathway eliminated the effects of GAA on apoptosis and proinflammatory cytokines release in hypoxia‐injured NSCs. Meanwhile, inhibition of the mTOR pathway abrogated the effects of GAA on cell autophagy in hypoxia‐injured NSCs. In conclusion, GAA alleviated hypoxia‐induced injury in NSCs might be through activating the PI3K/AKT and mTOR pathways.
Limited progress? The effect of external pressure for board gender diversity on the increase of female directors
Authors: Knippen Jennifer M. , Shen Wei , Zhu Qi
Published: March 2019

Research Summary

This study explores how external pressure for board gender diversity influences the increase of female directors. We propose that while external pressure has a positive effect on the increase of female directors on boards, it heightens the salience of gender in new director selection, making incumbent male directors more likely to treat the new female directors as outgroup members and consequently more likely to add them through addition of board seats rather than substitution of male directors. We further predict that new female directors added through additional board seats are less likely to serve on major board committees than those added through substitution of male directors. Results from a large sample of S&P 1,500 firms during 2004 to 2015 provide support our theoretical predictions.

Managerial Summary

Our study intends to enhance the understanding of how external pressure influences a firm's decision to increase the number of female directors on the board. We find that, although external pressure makes firms more likely to increase female directors, firms tend to do it through the addition of board seats rather than through the replacement of incumbent male directors to the extent that the increase is a response to the external pressure. Moreover, we find that new female directors added through addition of board seats are less likely to serve on major board committees than those added through replacement of male directors. These findings suggest that external pressure has a positive but limited effect on countering the gender bias on corporate boards toward female directors.
Hexagonal Boron Nitride Growth on Cu‐Si Alloy: Morphologies and Large Domains
Authors: Li Jidong , Hu Zhili , Yi Yangfan , Yu Maolin , Li Xuemei , Zhou Jianxin , Yin Jun , Wu Shiwei , Guo Wanlin
Published: March 2019

Controllable synthesis of high‐quality hexagonal boron nitride (h‐BN) is desired toward the industrial application of 2D devices based on van der Waals heterostructures. Substantial efforts are devoted to synthesize h‐BN on copper through chemical vapor deposition, which has been successfully applied to grow graphene. However, the progress in synthesizing h‐BN has been significantly retarded, and it is still challenging to realize millimeter‐scale domains and control their morphologies reliably. Here, the nucleation density of h‐BN on Cu is successfully reduced by over two orders of magnitude by simply introducing a small amount of silicon, giving rise to large triangular domains with maximum 0.25 mm lateral size. Moreover, the domain morphologies can be modified from needles, tree patterns, and leaf darts to triangles through controlling the growth temperature. The presence of silicon alters the growth mechanism from attachment‐limited mode to diffusion‐limited mode, leading to dendrite domains that are rarely observed on pure Cu. A phase‐field model is utilized to reveal the growing dynamics regarding B‐N diffusion, desorption, flux, and reactivity variables, and explain the morphology evolution. The work sheds lights on the h‐BN growth toward large single crystals and morphology probabilities.
A Stretchable and Flexible Cardiac Tissue–Electronics Hybrid Enabling Multiple Drug Release, Sensing, and Stimulation
Authors: Feiner Ron , Wertheim Lior , Gazit Danielle , Kalish Or , Mishal Gal , Shapira Assaf , Dvir Tal
Published: March 2019

Replacement of the damaged scar tissue created by a myocardial infarction is the goal of cardiac tissue engineering. However, once the implanted tissue is in place, monitoring its function is difficult and involves indirect methods, while intervention necessarily requires an invasive procedure and available medical attention. To overcome this, methods of integrating electronic components into engineered tissues have been recently presented. These allow for remote monitoring of tissue function as well as intervention through stimulation and controlled drug release. Here, an improved hybrid microelectronic tissue construct capable of withstanding the dynamic environment of the beating heart without compromising electronic or mechanical functionality is reported. While the reported system is enabled to sense the function of the engineered tissue and provide stimulation for pacing, an electroactive polymer on the electronics enables it to release multiple drugs in parallel. It is envisioned that the integration of microelectronic devices into engineered tissues will provide a better way to monitor patient health from afar, as well as provide facile, more exact methods to control the healing process.
Rational Design of Atomic Layers of Pt Anchored on Mo2C Nanorods for Efficient Hydrogen Evolution over a Wide pH Range
Authors: Qiu Yu , Wen Zhilin , Jiang Chaoran , Wu Xiaojun , Si Rui , Bao Jun , Zhang Qinghua , Gu Lin , Tang Junwang , Guo Xiaohui
Published: March 2019

Transition metal carbide compound has been extensively investigated as a catalyst for hydrogenation, for example, due to its noble metal‐like properties. Herein a facile synthetic strategy is applied to control the thickness of atomic‐layer Pt clusters strongly anchored on N‐doped Mo2C nanorods (Pt/N‐Mo2C) and it is found that the Pt atomic layers modify Mo2C function as a high‐performance and robust catalyst for hydrogen evolution. The optimized 1.08 wt% Pt/N‐Mo2C exhibits 25‐fold, 10‐fold, and 15‐fold better mass activity than the benchmark 20 wt% Pt/C in neutral, acidic, and alkaline media, respectively. This catalyst also represents an extremely low overpotential of −8.3 mV at current density of 10 mA cm−2, much better than the majority of reported electrocatalysts and even the commercial reference catalyst (20 wt%) Pt/C. Furthermore, it exhibits an outstanding long‐term operational durability of 120 h. Theoretical calculation predicts that the ultrathin layer of Pt clusters on Mo‐Mo2C yields the lowest absolute value of ΔGH*. Experimental results demonstrate that the atomic layer of Pt clusters anchored on Mo2C substrate greatly enhances electron and mass transportation efficiency and structural stability. These findings could provide the foundation for developing highly effective and scalable hydrogen evolution catalysts.
Defects Passivation With Dithienobenzodithiophene‐based π‐conjugated Polymer for Enhanced Performance of Perovskite Solar Cells
Authors: Li Xianqiang , Li Wenhui , Yang Yijie , Lai Xue , Su Qiang , Wu Dan , Li Gongqiang , Wang Kai , Chen Shuming , Sun Xiao Wei , Kyaw Aung Ko Ko
Published: March 2019

A dithienobenzodithiophene‐based π‐conjugated polymer consisting of fluorinated benzotriazole and benzothiadiazole is successfully applied through anti‐solvent method to passivate the defects of perovskite crystals. The fluorinated polymer interacts with under coordinated Pb2+ ions in the perovskite crystals to form Pb‐F bond which effectively passivates the defects. The trap density is reduced and the charge carrier transfer between the perovskite film and Spiro‐OMeTAD is also improved after passivation with the polymer. As a result, a power conversion efficiency (PCE) of 18.03% is achieved in the champion cell. After storing in an ambient environment with 60% relative humidity for 1000 h, the device still retains 90% of the original PCE. These results demonstrate that dithienobenzodithiophene‐based π‐conjugated polymers are promising materials for passivation of perovskite films to further improve the performance and stability of perovskite solar cells.
Impact Toughness and Fracture Structure about Welded Joints of Low Chromium Nickel Ferritic Stainless Steel Containing Ce/Ti
Authors: Meng Xiang‐Li , Fan Xi‐Ying , Guo Yong‐Huan
Published: March 2019

In order to improve the impact toughness and reduce inclusion, rare earth element Ce and stable element Ti are added in the low chromium nickel ferritic stainless steel welded joints and heat treatment. The Charpy test and tensile test are carried out and fracture structure are analyzed. The results show that when the ratio of Ce is 0.24% and Ti is 0.72% in welded joints of ferritic stainless steel, the mechanical properties is the best. The impact energy of welded joint is 9.4 times more than the samples without Ce and Ti, the impact toughness is also increased by 123.6% after heat treatment and the tensile strength increases by 41.9% The fracture structure is main ductile fracture and dimple, the shape of dimples is parabolic. The dimple is large and deep, and in the bottom of dimple has second phase particles. There is a few cleavage facets and river patterns in the fracture. After thermal cycling, the number of oxide particles reduce and the second phase particles are refined, so the impact toughness is improved.
Survival/Adaptation of Bone Marrow-Derived Mesenchymal Stem Cells After Long-Term Starvation Through Selective Processes
Authors: Ferro Federico , Spelat Renza , Shaw Georgina , Duffy Niamh , Islam Md Nahidul , O'Shea Paula M. , O'Toole Daniel , Howard Linda , Murphy J. Mary
Published: March 2019

After in vivo transplantation, mesenchymal stem cells (MSC) face an ischemic microenvironment, characterized by nutrient deprivation and reduced oxygen tension, which reduces their viability and thus their therapeutic potential. Therefore, MSC response to models of in vitro ischemia is of relevance for improving their survival and therapeutic efficacy. The aim of this study was to understand the survival/adaptive response mechanism that MSC use to respond to extreme culture conditions. Specifically, the effect of a long-term starvation on human bone marrow (hBM)-derived MSC cultured in a chemically defined medium (fetal bovine serum-free [SF] and human SF), either in hypoxic or normoxic conditions. We observed that hBM-MSC that were isolated and cultured in SF medium and subjected to a complete starvation for up to 75 days transiently changed their behavior and phenotype. However, at the end of that period, hBM-MSC retained their characteristics as determined by their morphology, DNA damage resistance, proliferation kinetic, and differentiation potential. This survival mode involved a quiescent state, confirmed by increased expression of cell cycle regulators p16, p27, and p57 and decreased expression of proliferating cell nuclear antigen (PCNA), Ki-67, mTOR, and Nanog. In addition, Jak/STAT (STAT6) antiapoptotic activity selected which cells conserved stemness and that supported metabolic, bioenergetic, and scavenging requirements. We also demonstrated that hBM-MSC exploited an autophagic process which induced lipid β-oxidation as an alternative energy source. Priming MSC by concomitant starvation and culture in hypoxic conditions to induce their quiescence would be of benefit to increase MSC survival when transplanted in vivo. Stem Cells  2019;37:813–827
NHC‐Stabilised Silyliumylidene Ions
Authors: Powley Samuel L. , Inoue Shigeyoshi
Published: March 2019

Donor‐stabilised silyliumylidene ions, from the parent [R−Si:]+, are a class of low‐valent silicon species which have received increasing research interest in the last several years. This interest began in the fundamental synthesis and characterisation of these compounds, but has since started to include more investigation into their further reactivity after several stable NHC‐stabilised silyliumylidene ions were reported. This personal account briefly discusses the history of the still‐young field of silyliumylidene ions followed by a more detailed discussion of published work from our group on the further development of silyliumylidene chemistry over the last four years.
Estimation of muscle pain based on Twitter data
Authors: Okumura Hiroki , Hayashi Hitoshi
Published: March 2019

To estimate muscle pain, data from Twitter posts, or tweets, with and without symptomatic remarks were collected using the Twitter API. We performed morphological analysis, weighting by TF‐IDF, and calculation of the cosine similarity between the tweets, and then used the results to estimate muscle pain. Evaluation experiments were conducted to examine whether tweets with symptomatic remarks shared higher cosine similarity among all tweets combined. The results indicate that Twitter data could be used to characterize muscle pain symptoms. © 2019 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
Web‐based application for threatened woodland caribou population modeling
Authors: Eacker Daniel R. , Hebblewhite Mark , Steenweg Robin , Russell Mike , Flasko Amy , Hervieux Dave
Published: March 2019

Woodland caribou (Rangifer tarandus caribou) are threatened in Canada, with population and distribution declines evident in most regions of the country. Causes of declines are linked to landscape change from forest fires and human development, notably forestry oil and gas activities, which result in caribou habitat loss and affect ecosystem food webs. The Federal Species at Risk Act requires effective protection and restoration of caribou habitat, with actions to increase caribou survival. These requirements call for effective monitoring of caribou population trends to gauge success. Many woodland caribou populations are nearly impossible to count using traditional aerial survey methods, but demographic‐based monitoring approaches can be used to estimate population trends based on population modeling of vital rates from marked animals. Monitoring programs have used a well‐known simple population model (the Recruitment‐Mortality [R/M] equation) to estimate demographic rates for woodland caribou, but have faced challenges in managing large data streams and providing transparency in the demographic estimation process. We present a stand‐alone statistical software application using open‐source software to permit efficient, transparent, and replicable demographic estimation for woodland caribou populations. We developed an easy‐to‐use, interactive web‐based application for the R/M population model that uses a Bayesian estimation approach and provides the user flexibility in choice of prior distributions and other output features. We illustrate the web‐application to the A la Pêche Southern Mountain (Central Group) woodland caribou population in west‐central Alberta, Canada, during 1998–2017. Our estimates of population demographics are consistent with previous research on this population and highlight the utility of the application in assessing caribou population responses to species recovery actions. We provide example data, computer code, the web‐based application package, and a user manual to guide installation and use. We also review underlying assumptions and challenges of population monitoring in this case study. We expect our software will contribute to efficient monitoring of woodland caribou and help in the assessment of recovery actions for this species. © 2019 The Authors. Wildlife Society Bulletin Published by Wiley Periodicals, Inc.
Comparing infrared imagery to traditional methods for estimating ringed seal density
Authors: Young Brent G. , Yurkowski David J. , Dunn J. Blair , Ferguson Steven H.
Published: March 2019

When conducting aerial surveys of wildlife populations, a number of animals go undetected by observers. The use of infrared imagery may offer a solution to improve detection rates and reduce visibility bias. Our objective was to compare the use of an infrared camera system with traditional methods using direct visual observations for estimating density of ringed seals (Pusa hispida) on ice. We conducted aerial surveys of ringed seals in the areas of Pond Inlet and western Hudson Bay in the Canadian Arctic during spring 2016 and 2017. Infrared videos were recorded within a 250‐m‐wide strip beneath the aircraft and potential seals were verified using corresponding visual images from a digital single‐lens reflex camera. Results from strip‐transect analysis of infrared observations were compared with results from strip‐transect analysis of direct visual observations and results from line‐transect analysis of a combined data set of infrared and direct visual observations. The different methods produced different density estimates with the infrared strip‐transect and line‐transect methods producing similar results that were, on average, approximately 2–3 times greater than strip‐transect analyses of observer data. Use of infrared imagery provides several advantages over traditional methods because it allows for more efficient and reliable detection of seals, eliminates the need for large teams of trained observers, and simplifies the process of data analysis and density estimation. © 2019 The Wildlife Society.