bluuebunny/crossref_metadata_2025_split huggingface dataset:
Experimental and numerical study on surface roughness of magnetorheological elastomer for controllable friction
Authors: Li Rui , Li Xi , Li Yuanyuan , Yang Ping-an , Liu Jiushan 
Published: October 2019

Abstract
Magnetorheological elastomer (MRE) is a type of smart material of which mechanical and electrical properties can be reversibly controlled by the magnetic field. In this study, the influence of the magnetic field on the surface roughness of MRE was studied by the microscopic modeling method, and the influence of controllable characteristics of the MRE surface on its friction properties was analyzed by the macroscopic experimental method. First, on the basis of existing studies, an improved mesoscopic model based on magnetomechanical coupling analysis was proposed. The initial surface morphology of MRE was characterized by the W-M fractal function, and the change process of the surface microstructures of MRE, induced by the magnetic interaction between particles, was studied. Then, after analyzing the simulation results, it is found that with the increase in the magnetic field and decrease in the modulus of rubber matrix, the surface of MRE changes more significantly, and the best particle volume fraction is within 7.5%–9%. Furthermore, through experimental observation, it is found that the height of the convex peak on the surface of MRE decreases significantly with the action of the magnetic field, resulting in a reduction in the surface roughness. Consistent with the simulation results, a particle volume fraction of 10% corresponds to a maximum change of 14%. Finally, the macroscopic friction experiment results show that the friction coefficients of MREs with different particle volume fractions all decrease with the decrease in surface roughness under the magnetic field. When the particle volume fraction is 10%, the friction coefficient can decrease by 24.7% under a magnetic field of 400 mT, which is consistent with the trend of surface roughness changes. This shows that the change in surface morphology with the effect of the magnetic field is an important factor in the control of MRE friction properties by magnetic field.
Influence of the cotton and silastic seton on the distance of the anal sphincter cables after fistulotomy in rats
Authors: Lima Ana Laura Sanches , Gianini Beatriz Schorro , Santana Bruna Miranda , Santos Carlos Henrique Marques dos , Dourado Doroty Mesquita , Falcão Juliano Seger , Bannwart Lucas , Câmara Sara Jéssica Falcão 
Published: October 2019

Abstract
Rationale Fistulotomy is a procedure widely used in the treatment of anal fistulas but is associated with varying degrees of fecal incontinence that could be minimized by previous use of sedentum, and the material used may influence the outcome.
Purpouse To compare cotton and silastic used as setons in the spacing of the sphincter cables of rats subjected to fistulotomy.
Method Thirty Wistar rats were used, which after 30 days of fistula production were distributed in: Control Group (GC): the steel wire was removed, followed by fistulotomy; Cotton Group (GA) and Silastic Group (GS), in which were applied cotton and silastic setons respectively for 30 days when fistulotomy was performed; after seven days, euthanasia and removal of the specimens were performed for histological study, and the results were submitted to statistical assessment using Kruskal–Wallis non-parametric test, establishing a significance level of p < 0.05.
Results The distance between the muscular cables was 107.9 μm in the GC, 82.4 μm in the GA and 53.5 μm in the GS (p = 0.00001). The mean inflammation scores were 1.9 in the CG, 1.0 in the GA and 0 in the GS (p < 0.05). The fibrosis scores were 1.1 in GC, 0.9 in GA and 0.6 in GS (p > 0.05).
Conclusion The silastic seton prior to fistulotomy caused less detachment of the muscular cables and less local inflammatory process.
Evaluation of Foveal Avascular Zone and Capillary Plexus in Smokers Using Optical Coherence Tomography Angiography
Authors: Çiloğlu Emine , Unal Fikret , Alyamac Sukgen Emine , Kocluk Yusuf , Dogan Nese Cetin 
Published: October 2019

Purpose:
To evaluate the macular microvasculature in smokers in comparison to healthy subjects using optical coherence tomography angiography (OCTA).

Methods:
Fifty chronic, regular smokers and 50 healthy non-smokers, as a control group, were recruited for the study. Foveal avascular zone (FAZ) area (mm2) and vessel density (VD) (%) in the superficial (SCP) and deep capillary plexus (DCP) were evaluated.

Results:
FAZ area was 0.424 ± 0.100 mm2 in the smoker group and 0.333 ± 0.093 mm2 in the non-smoking control group (P = 0.002). The deep foveal VD was 31.76 ± 6.33% in the smoker group and 53.09 ± 5.88% in the non-smoking control group (P = 0.006). Superficial foveal and parafoveal, deep parafoveal VD were not statistically different between the groups (P = 0.120), (P = 0.337), (P = 0.287), respectively.

Conclusion:
In our study, there was an enlargement of FAZ and reduction of foveal VD at DCP in the eyes of smokers compared with non-smoking adults.
A Systematic Review of Human Trials Using Stem Cell Therapy for Erectile Dysfunction
Authors: Lokeshwar Soum D. , Patel Premal , Shah Serena M. , Ramasamy Ranjith 
Published: October 2019

ABSTRACTIntroductionNovel therapeutic modalities have been proposed for the treatment and management of erectile dysfunction (ED). Stem cell therapy (SCT) is the injection of mesenchymal stem cells or stromal vascular fractions from adipose and other tissue sources. Although SCT has been studied and reported in multiple rodent trials, few human clinical trials exist.AimThe aim of this study was to provide a systematic review of SCT for the treatment of ED with an emphasis on data from peer-reviewed human studies.MethodsA systematic review was performed evaluating SCT for ED in human studies using PubMed-Medline and Scopus databases. Literature search was conducted using key words such as “Clinical Trials of SCT for ED,” “Stromal Vascular Fraction Treatment for ED,” and “SCT for ED.” Systematic review followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.Main Outcome MeasureThe main outcomes measure was the safety and efficacy of SCT for ED in humans.Results5 studies specific to SCT for ED treatment were included. A total of 61 patients were included in these phase I and II clinical trials and follow-up periods ranged from 6−62 months. End points of the studies included safety, tolerability, and efficacy of SCT for ED. The majority of the studies demonstrated improvement in erectile function due to SCT in patients, including improvements in penile vascular flow, International Index of Erectile Function-15 items, and Erectile Hardness Scale scores. All of the studies reported that there were no serious adverse events for patients. Limitations of the studies included small cohort sizes, and only 1 contained a sham arm.ConclusionThe 5 completed human clinical trials show promise for SCT as a restorative therapy for the treatment of ED. However, although promising, there still exists very limited data for the use of SCT for ED in humans. With the expansion of clinics offering SCT for ED, it is imperative that SCT is investigated further for safety, efficacy, and standardization.
Land‐Atmosphere Coupling Regimes in a Future Climate in Africa: From Model Evaluation to Projections Based on CORDEX‐Africa
Authors: Soares Pedro M. M. , Careto João A. M. , Cardoso Rita M. , Goergen Klaus , Trigo Ricardo M. 
Published: October 2019

AbstractLand‐atmosphere coupling plays a crucial role in determining the evolution of weather and climate. In the current study, the full ensemble of CORDEX‐Africa climate change simulations is used to understand how strong and weak coupling regions in Africa will evolve in the future. The ability of the regional climate models to capture the coupling signal relies on a reasonable representation of near surface air temperature, precipitation, surface fluxes, and soil moisture. A thorough model evaluation reveals typical shortcomings in the representation of the African climate, in particular seasonal precipitation. The multimodel ensemble mean outperforms the individual models and is therefore used for the investigation of the land‐atmosphere coupling. This ensemble mean shows a widespread warming in Africa and changes in precipitation, such as a decrease in the Sahel during summer and an increase in western Africa during summer and autumn. The coupling analysis relies on surface fluxes, the related evaporative fraction and their correlations as well as the correlation between evaporative fraction and soil moisture. Overall, water‐limited regions that exhibit a strong land‐atmosphere coupling are projected to expand further southward in West Africa and further northward in southern Africa. This is particularly true over the Sahel during spring and summer, when the strong coupling region shifts southward, indicating a potential expansion of the semiarid and arid regions. A transition of energy limited regimes, with weak coupling, to water‐limited regimes where soil moisture plays a more important role, is projected for the end of the 21st century as drying continues.
The Community Land Model Version 5: Description of New Features, Benchmarking, and Impact of Forcing Uncertainty
Authors: Lawrence David M. , Fisher Rosie A. , Koven Charles D. , Oleson Keith W. , Swenson Sean C. , Bonan Gordon , Collier Nathan , Ghimire Bardan , van Kampenhout Leo , Kennedy Daniel , Kluzek Erik , Lawrence Peter J. , Li Fang , Li Hongyi , Lombardozzi Danica , Riley William J. , Sacks William J. , Shi Mingjie , Vertenstein Mariana , Wieder William R. , Xu Chonggang , Ali Ashehad A. , Badger Andrew M. , Bisht Gautam , van den Broeke Michiel , Brunke Michael A. , Burns Sean P. , Buzan Jonathan , Clark Martyn , Craig Anthony , Dahlin Kyla , Drewniak Beth , Fisher Joshua B. , Flanner Mark , Fox Andrew M. , Gentine Pierre , Hoffman Forrest , Keppel‐Aleks Gretchen , Knox Ryan , Kumar Sanjiv , Lenaerts Jan , Leung L. Ruby , Lipscomb William H. , Lu Yaqiong , Pandey Ashutosh , Pelletier Jon D. , Perket Justin , Randerson James T. , Ricciuto Daniel M. , Sanderson Benjamin M. , Slater Andrew , Subin Zachary M. , Tang Jinyun , Thomas R. Quinn , Val Martin Maria , Zeng Xubin 
Published: October 2019

AbstractThe Community Land Model (CLM) is the land component of the Community Earth System Model (CESM) and is used in several global and regional modeling systems. In this paper, we introduce model developments included in CLM version 5 (CLM5), which is the default land component for CESM2. We assess an ensemble of simulations, including prescribed and prognostic vegetation state, multiple forcing data sets, and CLM4, CLM4.5, and CLM5, against a range of metrics including from the International Land Model Benchmarking (ILAMBv2) package. CLM5 includes new and updated processes and parameterizations: (1) dynamic land units, (2) updated parameterizations and structure for hydrology and snow (spatially explicit soil depth, dry surface layer, revised groundwater scheme, revised canopy interception and canopy snow processes, updated fresh snow density, simple firn model, and Model for Scale Adaptive River Transport), (3) plant hydraulics and hydraulic redistribution, (4) revised nitrogen cycling (flexible leaf stoichiometry, leaf N optimization for photosynthesis, and carbon costs for plant nitrogen uptake), (5) global crop model with six crop types and time‐evolving irrigated areas and fertilization rates, (6) updated urban building energy, (7) carbon isotopes, and (8) updated stomatal physiology. New optional features include demographically structured dynamic vegetation model (Functionally Assembled Terrestrial Ecosystem Simulator), ozone damage to plants, and fire trace gas emissions coupling to the atmosphere. Conclusive establishment of improvement or degradation of individual variables or metrics is challenged by forcing uncertainty, parametric uncertainty, and model structural complexity, but the multivariate metrics presented here suggest a general broad improvement from CLM4 to CLM5.
Parameterization and Surface Data Improvements and New Capabilities for the Community Land Model Urban (CLMU)
Authors: Oleson K. W. , Feddema J. 
Published: October 2019

AbstractThe Community Land Model Urban (CLMU) is an urban parameterization developed to simulate urban climate within a global Earth System Model framework. This paper describes and evaluates parameterization and surface data improvements, and new capabilities that have been implemented since the initial release of CLMU in 2010 as part of version 4 of the Community Land Model (CLM4) and the Community Earth System Model (CESM®). These include: 1) an expansion of model capability to simulate multiple urban density classes within each model grid cell; 2) a more sophisticated and realistic building space heating and air conditioning submodel; 3) a revised global dataset of urban morphological, radiative, and thermal properties utilized by the model, including a tool that allows for generating future urban development scenarios, and 4) the inclusion of a module to simulate various heat stress indices. The model and data are evaluated using observed data from five urban flux tower sites and a global anthropogenic heat flux (AHF) dataset. Generally, the new version of the model simulates urban radiative and turbulent fluxes, surface temperatures, and AHF as well or better than the previous version. Significant improvements in the global and regional simulation of AHF are also demonstrated that are primarily due to the new building energy model. The new model is available as part of the public release of CLM5 and CESM2.0.
Coral Records of Variable Stress Impacts and Possible Acclimatization to Recent Marine Heat Wave Events on the Northwest Shelf of Australia
Authors: Clarke H. , D'Olivo J. P. , Conde M. , Evans R. D. , McCulloch M. T. 
Published: October 2019

AbstractThe ability of massive corals to record the impacts of marine heat wave events provides a unique perspective into the variable responses of corals to anthropogenic climate change. In this study, coral cores (Porites spp.) were collected from seven reef sites across the inner‐, mid‐, and outer‐NW shelf of Australia, to examine seasonal patterns of trace element (TE), Sr/Ca and Li/Mg ratios, and extension rate signatures associated with past marine heat waves in the region. TE anomalies and declines in linear extension rate were observed in the records during the late 1990s (two of five records) and more recently during the summers of 2011 (three of seven records) and 2013 (five of seven records), indicating the impacts of marine heat waves have become increasingly widespread in the region. However, for the summers of 2011 and 2013, no significant relationships were observed between the magnitude of these TE ratio anomalies in the core records and maximum thermal stresses predicted at the reef sites from high‐resolution satellite records. We show that the strongest individual reductions in linear extension rates and associated TE ratio anomalies occurred during the 2011 heat wave, rather than during the subsequent and more intense (~1 °C warmer) 2013 event. Together, these observations suggest that at the local reef scale, Porites spp. colonies and their symbionts exhibit differential responses to heat wave events, with the prior exposure to less intense events probably playing an important role in acclimatization.
Comment on “Climate Impact of a Regional Nuclear Weapon Exchange: An Improved Assessment Based on Detailed Source Calculations” by Reisner et al.
Authors: Robock Alan , Toon Owen B. , Bardeen Charles G. 
Published: October 2019

AbstractReisner et al. revisited a study we had done modeling the climate impacts of a nuclear war between India and Pakistan, in which fires started by 100 15‐kt atomic bombs would produce 5 Tg of soot injected into the upper troposphere, and subsequently lofted into the lower stratosphere. Their claim that there would be much less smoke than in our results is wrong for several reasons. They chose a target area of suburban Atlanta that includes a golf course, playground, and individual houses with large yards, with little material to burn, which is not representative of densely populated cities in India and Pakistan. The fire they modeled is not typical of the type of mass fire likely to result from a nuclear attack on cities. They used winds that are stronger than typical winds. They did not allow moist convection, which would be important in convective lofting of the smoke. Their claim that if they included convection the resulting rain would wash out the smoke is not supported by observations of pyrocumulonimbus injection of smoke into the stratosphere from forest fires. And they used a fire model that they have not made available for other scientists to try to reproduce their work, and which has not been shown to accurately simulate firestorms observed in Hamburg, Dresden, and Hiroshima during World War II. They significantly underestimate the amount of smoke, and climate and agricultural impacts likely after a nuclear war.
Reply to Comment by Robock et al. on “Climate Impact of a Regional Nuclear Weapon Exchange: An Improved Assessment Based on Detailed Source Calculations”
Authors: Reisner Jon , Koo Eunmo , Hunke Elizabeth , Dubey Manvendra 
Published: October 2019

Key Points

firestorms are difficult to form
black carbon source scales in a nonlinear fashion with regard to fuel load
Reisner et al.'s paper was indeed the worst case
Correlation Between Shoreline Change and Planform Curvature on Wave‐Dominated, Sandy Coasts
Authors: Lauzon R. , Murray A. B. , Cheng S. , Liu J. , Ells K. D. , Lazarus E. D. 
Published: October 2019

AbstractLow‐lying, wave‐dominated, sandy coastlines can exhibit high rates of shoreline change that may impact coastal infrastructure, habitation, recreation, and economy. Efforts to understand and quantify controls on shoreline change typically examine factors such as sea‐level rise; anthropogenic modifications; geologic substrate, nearshore bathymetry, and regional geography; and sediment grain size. The role of shoreline planform curvature, however, tends to be overlooked. Theoretical and numerical model considerations indicate that incident offshore waves interacting with even subtle shoreline curvature can drive gradients in net alongshore sediment flux that can cause significant erosion or accretion. However, these predictions or assumptions have not often been tested against observations, especially over large spatial and temporal scales. Here, we examined the correlation between shoreline curvature and shoreline change rates for spatially extended segments of the U.S. Atlantic and Gulf Coasts (~1,700 km total). Where shoreline stabilization (nourishment or hard structures) does not dominate the shoreline change signal, we find a significant negative correlation between shoreline curvature and shoreline change rates (i.e., convex‐seaward curvature [promontories] is associated with shoreline erosion, and concave‐seaward curvature [embayments] with accretion) at spatial scales of 1–5 km alongshore and timescales of decades to centuries. This indicates that shoreline changes observed in these reaches can be explained in part by gradients in alongshore sediment flux acting to smooth spatial variations in shoreline curvature. Our results suggest that shoreline curvature should be included as a key variable in modeling and risk assessment of coastal change on wave‐dominated, sandy coastlines.
Reduction‐Oxidation Potential and Dissolved Organic Matter Composition in Northern Peat Soil: Interactive Controls of Water Table Position and Plant Functional Groups
Authors: Kane E. S. , Veverica T. J. , Tfaily M. M. , Lilleskov E. A. , Meingast K. M. , Kolka R. K. , Daniels A. L. , Chimner R. A. 
Published: October 2019

AbstractGlobally important carbon (C) stores in northern peatlands are vulnerable to oxidation in a changing climate. A growing body of literature draws attention to the importance of dissolved organic matter (DOM) in governing anaerobic metabolism in organic soil, but exactly how the reduction‐oxidation (redox) activities of DOM, and particularly the phenolic fraction, are likely to change in an altered climate remain unclear. We used large mesocosms in the PEATcosm experiment to assess changes in peatland DOM and redox potential in response to experimental manipulations of water table (WT) position and plant functional groups (PFGs). WT position and PFGs interacted in their effects on redox potential and quantity and quality of DOM. Phenolics were generally of higher molecular weight and more oxidized with sedges in lowered WTs. Altered DOM character included changes in dissolved nitrogen (N), with higher N:[phenolics] with higher E4:E6 (absorbance ratio λ = 465:665) DOM in the lowered WT and sedge PFG treatments. Conversely, biomolecular assignments to amino‐sugars were largely absent from low‐WT treatments. Low WT resulted in the creation of unique N compounds, which were more condensed (lower H:C), that changed with depth and PFG. The accumulation of oxidized compounds with low WT and in sedge rhizospheres could be very important pools of electron acceptors beneath the WT, and their mechanisms of formation are discussed. This work suggests the effects of changes in vegetation communities can be as great as WT position in directly and interactively mediating peat redox environment and the redox‐activity of DOM.
Biogeochemical Behavior of Metals Along Two Permeable Reactive Barriers in a Mining‐Affected Wetland
Authors: von Gunten Konstantin , Bishop Brendan , Zhang Luyu , Muehlenbachs Karlis , Alam Md. Samrat , Konhauser Kurt O. , Alessi Daniel S. 
Published: October 2019

AbstractThe biogeochemistry of two alkaline permeable reactive barriers (PRBs) installed for remediation in a mining‐affected wetland was investigated in order to assess the importance of colloidal particles on metal removal processes in such systems. At the time of investigation, both PRBs were effective in removing U, Cu, and Zn (>95%) from groundwater but were slightly less efficient for Ni and Co (<90%). Previously installed groundwater wells allowed an in‐depth analysis of groundwater passing through the first PRB. Here, in an alkaline environment (pH 6.0–9.7), 11–14% of Ni, 36–37% of Co, 77–81% of Cu, 14–17% of U, and 10–19% of Fe were associated with organic matter and inorganic colloids, while upgradient in the more acidic environments (pH <6.0), ionic species and complexes (e.g., Co2+, Ni2+, Cu2+, and UO2H3SiO4+) dominated. Copper and U preferentially bound to larger colloidal fractions (>1 kDa), which might have promoted their sequestration. Uranium removal was likely further enhanced by U (VI) reduction in the alkaline and oxygen‐depleted conditions of the PRBs. The less efficient removal of Ni and Co, being target metals for remediation, was explained by a combination of their high solubility, unfavorable redox and pH conditions created by the alkaline PRBs, and their limited association with colloidal particles. These considerations are critical in the design of future PRBs for the remediation of similar systems.