bluuebunny/crossref_metadata_2025_split huggingface dataset:
Superior performing nano‐enabled metal oxide varistors
Authors: Tan Daniel Q. 
Published: July 2019

AbstractCommercial metal oxide varistor devices are subject to nonuniformity, defects and coarse grain size, low working voltage, high leakage current, and mechanical cracking issues. This work tempted to make use of nanopowders and alternative sintering processes to achieve uniform microstructure and superior varistor performance. These nano‐enabled compositions exhibit lower sintering temperatures (650‐1050°C), smaller grain sizes (0.5‐2 μm), enhanced nonlinear coefficient (30‐130) in DC I‐V characteristics, higher varistor voltages (240‐2500 V/mm), and low leakage current (<1 μA/cm2). Conventional sintering offers highest nonlinearity. Spark plasma sintering and microwave sintering techniques show advantages in reducing grain sizes and sintering temperatures. Spark plasma sintering is particularly effective in achieving better varistor performance for the nano‐enabled MOV compositions after a post‐SPS sintering for sufficient oxygen diffusion. Microwave sintering needs higher sintering temperatures and additional research for the nano‐enabled MOV compositions to offer equivalent electrical properties.
Total Synthesis of the Endocannabinoid Uptake Inhibitor Guineensine and SAR Studies
Authors: Bartholomäus Ruben , Nicolussi Simon , Baumann Alice , Rau Mark , Simão Ana Catarina , Gertsch Jürg , Altmann Karl‐Heinz 
Published: July 2019

AbstractGuineensine ((2E,4E,12E)‐13‐(benzo[d][1,3]dioxol‐5‐yl)‐N‐isobutyltrideca‐2,4,12‐trienamide) is a plant‐derived natural product that inhibits reuptake of the endocannabinoid anandamide with sub‐micromolar potency. We have established a highly efficient total synthesis of guineensine, which provided the natural product in only five steps from commercially available 3‐nonyn‐1‐ol in 17 % overall yield, relying on the attachment of the benzodioxolyl moiety to the unsaturated fatty acid chain by means of a Suzuki coupling as the key step. Subsequent SAR studies revealed that replacement of the N‐isobutyl group in the natural product by various alkyl, arylalkyl, or aryl groups is generally well tolerated, and derivatives could be identified that are slightly more potent anandamide reuptake inhibitors than guineensine itself. In contrast, modifications of the benzodioxolyl moiety led to decreased activity. Intriguingly, a change in the configuration of the C4=C5 double bond from E to Z was found to be very well tolerated, in spite of the associated change in the overall geometry of the molecule.
Novel type of sub‐retinal pigment shield in the miniaturized compound eye of Trichogramma evanescens
Authors: Mohr Tobias , Meinertzhagen Ian A. , Fischer Stefan 
Published: July 2019

AbstractPigment granules, found in different cell types of the retina in insect compound eyes, fulfill important functions. They isolate the individual ommatidia from stray light, regulate the angular sensitivity, and restrict the light that reaches the photoreceptor according to ambient light intensities. Descriptions of pigment cells within the retina are included in ultrastructural eye descriptions, but knowledge of pigment cell types beneath the retina and basal matrix (BM) are relatively limited in insects. In the miniaturized parasitoid wasp Trichogramma evanescens Westwood 1833, a sub‐retinal pigment shield is formed by pigment‐bearing cells, which appear in two‐dimensional TEM sections to form a separate population beneath the BM. By using three‐dimensional reconstructions of serial‐section transmission electron microscopy, it was possible to reveal that the sub‐retinal pigment shield of T. evanescens is not formed by a separate cell type, but by extensions of the lateral rim pigment cells that penetrate gaps in the BM. The reconstruction is supported by evidence from a statistical analysis of pigment granule volumes of all pigment bearing cell types in the retina and rim region. The study reveals the first known case of the participation of lateral rim cells in a sub‐retinal pigment shield in an insect eye. As neither pigmented extensions of secondary pigment cells, nor pigment granules in the extensions of the cone cell projections are present above the BM in T. evanescens, the sub‐retinal extensions of the lateral rim cells can be seen as a functional adaptation to miniaturization in order to maintain a proximal shielding function.
The effect of miniaturized manual versus mechanical instruments on calculus removal and root surface characteristics: An in vitro light microscopic study
Authors: Profili Fabia , Sparabombe Scilla , Tawse Smith Andrew , D'Isidoro Orlando , Quaranta Alessandro 
Published: July 2019

AbstractObjectivesThe aim of this study was to evaluate by light microscopy analysis the effect of the use of miniaturised piezoelectric tips versus mini‐five area specific curets on calculus removal and postoperative root surface alterations.MethodsA total of 20 extracted teeth were used. Two square surfaces (5×5 mm) were marked on each root surface with a diamond bur mounted on a high‐speed handpiece. Before and after instrumentation, a series of magnified images (4.2×) of each experimental surface were taken with a standardized approach. According to a randomization list, the two surfaces on each sample were instrumented in a standardised fashion either with a mine‐five curet or a slim piezoelectric tip. The images were processed using an imaging software. Data were summarised as means and standard deviations for the two outcomes (calculus and alterations.) at each time (pre and post) for both of the groups (manual and mechanical).ResultsBoth manual and mechanical instrumentation significantly reduced the calculus deposits (p < .001) without significant differences between the two groups. Both manual and mechanical treatments significantly increased alterations (p < .01). There was a statistically significant evidence of a greater increase in alterations from mechanical treatment.ConclusionsSlim mechanical piezoelectric tips and manual mini‐five area‐specific curets have similar effects on calculus removal. Manual instrumentation results in a more homogeneous postoperative root surface with less root alterations.
Female directors and gender issues reporting: The impact of stakeholder engagement at country level
Authors: García‐Sánchez Isabel‐María , Oliveira Marcelle Colares , Martínez‐Ferrero Jennifer 
Published: July 2019

AbstractRecent studies have investigated how women on boards impact corporate social responsibility reporting, a voluntary strategy clearly influenced by board composition in general and gender diversity in particular. However, this research goes further and proposes to provide evidence about how female directors influence gender issues reporting. Moreover, this research also examines the moderating effect between gender diversity on boards and country‐level factors related to stakeholder orientation. For an international sample of 8,609 firm‐year observations from 2007 to 2016 and by regressing several logit models for panel data, it was found that female directors increase the probability of voluntary reporting on gender issues. Moreover, the findings also suggest that institutional forces related to stakeholder pressures reinforce this effect; the greater reporting on gender issues that female directors achieve is even higher when firms are located in stakeholder‐oriented countries.
Exploring the role of hydraulic conductivity on the contribution of the hyporheic zone to in‐stream nitrogen uptake
Authors: Mendoza‐Lera Clara , Ribot Miquel , Foulquier Arnaud , Martí Eugènia , Bonnineau Chloé , Breil Pascal , Datry Thibault 
Published: July 2019

AbstractNitrogen uptake (N‐uptake) within the hyporheic zone provides key ecological services, such as nutrient removal, of stream ecosystems. We hypothesize that the hydraulic conductivity (Kf) of the hyporheic sediments governs nutrient uptake rates through effects on the (a) surface and subsurface flow (i.e., hyporheic flow) and (b) hyporheic N‐uptake. Here, we worked at two hierarchical spatial scales (reach and hyporheic scale) to disentangle the role of Kf on N‐uptake. At the reach scale, we performed coinjected N‐NH4+ and Cl– additions in six reaches with contrasting reach Kf (10−1–10−5 m/s) and simultaneously determined (a) in‐stream N‐uptake (hyporheic+benthic N‐uptake) and (b) hyporheic flow, and (c) N‐uptake and microbial community abundance at the hyporheic scale. Results suggest that Kf determines the contribution of the hyporheic zone to hydrological exchange but that its role varies between scales to determine in‐stream N‐uptake. At the reach scale, Kf variability seems to determine the extent at which the hyporheic zone contributes to hyporheic flow and, thus, to N‐uptake velocity. At the hyporheic scale, Kf seems to indirectly determine hyporheic N‐uptake through the proportion of surface water that enters the hyporheic zone (i.e., relative connectivity) and the abundance of the microbial community. These results suggest an interplay between Kf at both scales and its spatial heterogeneity, which will ultimately drive in‐stream N‐uptake at reach scale. In this sense, we found that Kf can be considered as a unifying variable for stream biogeochemical processes and as an important variable to derive the contribution of hyporheic zone to in‐stream nutrient removal capacity.
Enhanced activity of soil nutrient‐releasing enzymes after plant invasion: a meta‐analysis
Authors: Zhou Yong , Staver A. Carla 
Published: July 2019

AbstractPlant invasion can significantly alter soil nutrient cycling of ecosystems. How these changes are linked to soil enzyme activities is still unknown, however, even though these are proximate agents of organic matter decomposition and nutrient release. We performed a meta‐analysis of 60 case studies examining responses of 10 unique soil enzymes to plant invasion, and tested whether invaded soils differed in their enzyme activities from uninvaded soils. We also examined whether increases in soil nutrient‐releasing enzyme activity were paralleled by enhanced soil nutrient availability after plant invasion. Overall, we found that plant invasion had significant impacts on the activities of seven types of soil enzymes. Plant invasion had inconsistent impacts on C‐decomposing enzymes, but invaded sites had significantly higher activities of soil enzymes related to N‐ and P‐release than noninvaded sites. Increases in nutrient‐releasing enzyme activity after plant invasion ranged from +23% to +69%, which potentially results in a linear increase of soil nutrient availability in response to enhanced enzyme activities. Invaded soils also had higher nutrient stocks and soil microbial biomass than uninvaded soils. Our results suggest that enhanced activity of soil nutrient‐releasing enzymes after plant invasion may accelerate nutrient cycling, potentially creating a nutrient‐rich soil environment that benefits invaders and promotes their persistence, as invasive plants often appear to be more resource‐demanding and competitive than native species.
Facile Solution Processing of Stable MXene Dispersions towards Conductive Composite Fibers
Authors: Seyedin Shayan , Zhang Jizhen , Usman Ken Aldren S. , Qin Si , Glushenkov Alexey M. , Yanza Elliard Roswell S. , Jones Robert T. , Razal Joselito M. 
Published: July 2019

Abstract2D transition metal carbides and nitrides called “MXene” are recent exciting additions to the 2D nanomaterials family. The high electrical conductivity, specific capacitance, and hydrophilic nature of MXenes rival many other 2D nanosheets and have made MXenes excellent candidates for diverse applications including energy storage, electromagnetic shielding, water purification, and photocatalysis. However, MXene nanosheets degrade relatively quickly in the presence of water and oxygen, imposing great processing challenges for various applications. Here, a facile solvent exchange (SE) processing route is introduced to produce nonoxidized and highly delaminated Ti3C2Tx MXene dispersions. A wide range of organic solvents including methanol, ethanol, isopropanol, butanol, acetone, dimethylformamide, dimethyl sulfoxide, chloroform, dichloromethane, toluene, and n‐hexane is used. Compared to known processing approaches, the SE approach is straightforward, sonication‐free, and highly versatile as multiple solvent transfers can be carried out in sequence to yield MXene in a wide range of solvents. Conductive MXene polymer composite fibers are achieved by using MXene processed via the solvent exchange (SE) approach, while the traditional redispersion approach has proven ineffective for fiber processing. This study offers a new processing route for the development of novel MXene‐based architectures, devices, and applications.
Physical function‐derived cut‐points for the diagnosis of sarcopenia and dynapenia from the Canadian longitudinal study on aging
Authors: Tessier Anne‐Julie , Wing Simon S. , Rahme Elham , Morais José A. , Chevalier Stéphanie 
Published: July 2019

AbstractBackgroundAging is associated with sarcopenia (low muscle mass) and dynapenia (low muscle strength) leading to disability and mortality. Widely used previous cut‐points for sarcopenia were established from dated, small, or pooled cohorts. We aimed to identify cut‐points of low strength as a determinant of impaired physical performance and cut‐points of low appendicular lean mass (ALM) as a predictor of low strength in a single, large, and contemporary cohort of community‐dwelling older adults and compare these criteria with others.MethodsCross‐sectional analyses were conducted on baseline data from 4725 and 4363 community‐dwelling men and women (65–86 years, 96.8% Caucasian) of the Canadian longitudinal study on aging comprehensive cohort. Physical performance was evaluated from gait speed, timed up‐and‐go, chair rise, and balance tests; a weighted‐sum score was computed using factor analysis. Strength was measured by handgrip dynamometry; ALM, by dual‐energy X‐ray absorptiometry and ALM index (ALMI; kg/m2), was calculated. Classification and regression tree analyses determined optimal sex‐specific cut‐points of ALMI predicting low strength and of strength predicting impaired physical performance (score < 1.5 SD below the sex‐specific mean).ResultsModest associations were found between ALMI and strength and between strength and physical performance score in both sexes. ALMI was not an independent predictor of physical performance score. Cut‐points of <33.1 and <20.4 kg were found to define dynapenia in men and in women, respectively, corresponding to 21.5% and 24.0% prevalence rates. Sarcopenia cut‐points were <7.76 kg/m2 in men and <5.72 kg/m2 in women; prevalence rates of 21.7% and 13.7%. Overall, 8.3% of men and 5.5% of women had sarco‐dynapenia. Sarcopenic were older and had lower fat mass and body mass index (BMI) than non‐sarcopenic participants. While the agreement between current criteria and the updated European Working Group for Sarcopenia in Older Persons recommendations was fair, we found only slight agreement with the Foundation for the National Institute of Health sarcopenia project. Older persons identified with sarcopenia as per the Foundation for the National Institute of Health criteria (using ALM/BMI as the index) have higher BMI and fat mass compared with non‐sarcopenic and have normal ALMI as per our criteria.ConclusionsThe proposed function‐derived cut‐points established from this single, large, and contemporary Canadian cohort should be used for the identification of sarcopenia and dynapenia in Caucasian older adults. We advise on using criteria based on ALMI in the diagnosis of sarcopenia. The modest agreement between sarcopenia and dynapenia denotes potential distinct health implications justifying to study both components separately.
Sensitivity and specificity of meningeal signs in patients with meningitis
Authors: Akaishi Tetsuya , Kobayashi Junpei , Abe Michiaki , Ishizawa Kota , Nakashima Ichiro , Aoki Masashi , Ishii Tadashi 
Published: July 2019

AbstractBackgroundSeveral types of physical examinations are used in the diagnosis of meningitis, including nuchal rigidity, jolt accentuation, Kernig's sign, and Brudzinski's sign. Jolt accentuation was reported to have sensitivity of nearly 100% and to be highly efficient for excluding meningitis, but more recent studies showed that a number of patients with meningitis may present negative in this test.MethodsWe systematically reviewed studies on the above‐mentioned physical examination tests and performed meta‐analysis of their diagnostic characteristics to evaluate the clinical usefulness. Nine studies, comprising a total of 599 patients with pleocytosis in the cerebrospinal fluid (CSF) and 1216 patients without CSF pleocytosis, were enrolled in the analysis.ResultsJolt accentuation showed a decent level of odds ratio (3.62; 99% confidence interval (CI): 1.13‐11.60, P = 0.004) comparable to that in nuchal rigidity (2.52; 1.21‐5.27, P = 0.001) for the correct prediction of CSF pleocytosis among subjects with suspected meningitis. The estimated sensitivity was relatively high (40%‐60%) in nuchal rigidity or jolt accentuation tests. On the other hand, Kernig's and Brudzinski's signs exhibited relatively low sensitivity (20%‐30%). The estimated specificity was higher in Kernig's and Brudzinski's signs (85%‐95%) than in nuchal rigidity or jolt accentuation tests (65%‐75%).ConclusionApproximately half of the patients with meningitis may not present typical meningeal signs upon physical examination. Combining several examinations for the detection of meningeal signs may decrease the risk of misdiagnosis.
Effect of aspirin use on gastric cancer incidence and survival: A systematic review and meta‐analysis
Authors: Niikura Ryota , Hirata Yoshihiro , Hayakawa Yoku , Kawahara Takuya , Yamada Atsuo , Koike Kazuhiko 
Published: July 2019

Background and AimA number of recent studies have been published evaluating the chemopreventive effect of aspirin against gastric cancer, and an updated meta‐analysis is required to evaluate this relationship further. This study presents a meta‐analysis of studies examining the effect of aspirin on gastric cancer incidence and death.MethodsThe PUBMED and Cochrane Central Registration of Controlled Trials databases were searched for eligible studies published up to December 2018. Pooled risk ratios for gastric cancer incidence and death in aspirin users versus nonusers were determined using fixed‐ and random‐effects models. The influence of the frequency of aspirin use, duration of aspirin use, and geographic location on gastric cancer incidence was evaluated.ResultsThe meta‐analysis comprised 33 studies with a total of 1 927 971 patients. The pooled risk ratios for gastric cancer incidence in the fixed‐ and random‐effects models were 0.890 (95% confidence interval, 0.871–0.909) and 0.826 (0.740–0.922), respectively. In Asia and North America, the maximum preventive benefit of aspirin use was observed with weekly or daily use. Aspirin use was most effective for noncardiac gastric cancer. The pooled risk ratios for gastric cancer death in the fixed‐ and random‐effects models were 0.798 (0.749–0.850) and 0.894 (0.780–1.024), respectively. Significant heterogeneity was observed among studies of gastric cancer incidence but not gastric cancer death.ConclusionAspirin use may reduce the risk of gastric cancer incidence and death; however, the relationship may be limited to a specific frequency and duration of aspirin use and geographic location.
The effects of age and sex on the detection of pure tones by adult CBA/CaJ mice (Mus musculus)
Authors: Kobrina Anastasiya , Dent Micheal L. 
Published: July 2019

AbstractAge‐related hearing loss (ARHL) is a neurodegenerative disorder characterized by a gradual decrease in hearing sensitivity. Previous electrophysiological and behavioral studies have demonstrated that the CBA/CaJ mouse strain is an appropriate model for the late‐onset hearing loss found in humans. However, few studies have characterized hearing in these mice behaviorally using longitudinal methodologies. The goal of this research was to utilize a longitudinal design and operant conditioning procedures with positive reinforcement to construct audiograms and temporal integration functions in aging CBA/CaJ mice. In the first experiment, thresholds were collected for 8, 16, 24, 42, and 64 kHz pure tones in 30 male and 35 female CBA/CaJ mice. Similar to humans, mice had higher thresholds for high frequency tones than for low frequency pure tones across the lifespan. Female mice had better hearing acuity than males after 645 days of age. In the second experiment, temporal integration functions were constructed for 18 male and 18 female mice for 16 and 64 kHz tones varying in duration. Mice showed an increase in thresholds for tones shorter than 200 ms, reaching peak performance at shorter durations than other rodent species. Overall, CBA/CaJ mice experience ARHL for pure tones of different frequencies and durations, making them a good model for studies on hearing loss. These findings highlight the importance of using a wide range of stimuli and a longitudinal design when comparing presbycusis across different species.
Kinematic Evaluation of the GMK Sphere Implant During Gait Activities: A Dynamic Videofluoroscopy Study
Authors: Schütz Pascal , Taylor William R. , Postolka Barbara , Fucentese Sandro F. , Koch Peter P. , Freeman Michael A.R. , Pinskerova Vera , List Renate 
Published: July 2019

ABSTRACTJoint stability is a primary concern in total knee joint replacement. The GMK Sphere prosthesis was specifically designed to provide medial compartment anterior–posterior (A–P) stability, while permitting rotational freedom of the joint through a flat lateral tibial surface. The objective of this study was to establish the changes in joint kinematics introduced by the GMK Sphere prosthesis during gait activities in comparison to conventional posterior‐stabilized (PS) fixed‐bearing and ultra‐congruent (UC) mobile‐bearing geometries. The A–P translation and internal/external rotation of three cohorts, each with 10 good outcome subjects (2.9 ± 1.6 years postop), with a GMK Sphere, GMK PS or GMK UC implant were analysed throughout complete cycles of gait activities using dynamic videofluoroscopy. The GMK Sphere showed the smallest range of medial compartment A–P translation for level walking, downhill walking, and stair descent (3.6 ± 0.9 mm, 3.1 ± 0.8 mm, 3.9 ± 1.3 mm), followed by the GMK UC (5.7 ± 1.0 mm, 8.0 ± 1.7 mm, 8.7 ± 1.9 mm) and the GMK PS (10.3 ± 2.2 mm, 10.1 ± 2.6 mm, 11.6 ± 1.6 mm) geometries. The GMK Sphere exhibited the largest range of lateral compartment A–P translation (12.1 ± 2.2 mm), and the largest range of tibial internal/external rotation (13.2 ± 2.2°), both during stair descent. This study has shown that the GMK Sphere clearly restricts A–P motion of the medial condyle during gait activities while still allowing a large range of axial rotation. The additional comparison against the conventional GMK PS and UC geometries, not only demonstrates that implant geometry is a key factor in governing tibio‐femoral kinematics, but also that the geometry itself probably plays a more dominant role for joint movement than the type of gait activity. © 2019 The Authors. Journal of Orthopaedic Research® published by Wiley Periodicals, Inc. on behalf of Orthopaedic Research Society. J Orthop Res 37:2337–2347, 2019
Rings whose ideals are isomorphic to trace ideals
Authors: Kobayashi Toshinori , Takahashi Ryo 
Published: July 2019

AbstractLet R be a commutative noetherian ring. Lindo and Pande have recently posed the question asking when every ideal of R is isomorphic to some trace ideal of R. This paper studies this question and gives several answers. In particular, a complete answer is given in the case where R is local: it is proved in this paper that every ideal of R is isomorphic to a trace ideal if and only if R is an artinian Gorenstein ring, or a 1‐dimensional hypersurface with multiplicity at most 2, or a unique factorization domain.