bluuebunny/crossref_metadata_2025_split huggingface dataset:
Katabatic Wind‐Driven Exchange in Fjords
Authors: Spall Michael A. , Jackson Rebecca H. , Straneo Fiammetta 
Published: September 2017

AbstractThe general issue of katabatic wind‐driven exchange in fjords is considered using an idealized numerical model, theory, and observations. Two regimes are identified. For fjords narrower than a viscous boundary layer width, the exchange is limited by a balance between wind and friction in lateral boundary layers. For the nonlinear viscous parameterization used here, this boundary layer thickness depends on the properties of the fjord, such as stratification and length, as well as on the wind stress and numerical parameters such as grid spacing and an empirical constant. For wider fjords typical of east Greenland, the balance is primarily between wind, the along‐fjord pressure gradient, and acceleration, in general agreement with previous two‐layer nonrotating theories. It is expected that O(10%) of the surface layer will be flushed out of the fjord by a single wind event. Application of the idealized model to a typical katabatic wind event produces outflowing velocities that are in general agreement with observations in Sermilik Fjord, a large glacial fjord in southeast Greenland. The presence of a sill has only a minor influence on the exchange until the sill penetrates over most of the lower layer thickness, in which cases the exchange is reduced. It is concluded that the multiple katabatic wind events per winter that are experienced by the fjords along east Greenland represent an important mechanism of exchange between the fjord and shelf, with implications for the renewal of warm, salty waters at depth and for the export of glacial freshwater in the upper layer.
Bottom Water Acidification and Warming on the Western Eurasian Arctic Shelves: Dynamical Downscaling Projections
Authors: Wallhead P. J. , Bellerby R. G. J. , Silyakova A. , Slagstad D. , Polukhin A. A. 
Published: September 2017

AbstractThe impacts of oceanic CO2uptake and global warming on the surface ocean environment have received substantial attention, but few studies have focused on shelf bottom water, despite its importance as habitat for benthic organisms and demersal fisheries such as cod. We used a downscaling ocean biogeochemical model to project bottom water acidification and warming on the western Eurasian Arctic shelves. A model hindcast produced 14–18 year acidification trends that were largely consistent with observational estimates at stations in the Iceland and Irminger Seas. Projections under SRES A1B scenario revealed a rapid and spatially variable decline in bottom pH by 0.10–0.20 units over 50 years (2.5%–97.5% quantiles) at depths 50–500 m on the Norwegian, Barents, Kara, and East Greenland shelves. Bottom water undersaturation with respect to aragonite occurred over the entire Kara shelf by 2040 and over most of the Barents and East Greenland shelves by 2070. Shelf acidification was predominantly driven by the accumulation of anthropogenic CO2, and was concurrent with warming of 0.1–2.7°C over 50 years. These combined perturbations will act as significant multistressors on the Barents and Kara shelves. Future studies should aim to improve the resolution of shelf bottom processes in models, and should consider the Kara Sea and Russian shelves as possible bellwethers of shelf acidification.
Evaluation of WRF Simulations With Different Selections of Subgrid Orographic Drag Over the Tibetan Plateau
Authors: Zhou X. , Beljaars A. , Wang Y. , Huang B. , Lin C. , Chen Y. , Wu H. 
Published: September 2017

AbstractWeather Research and Forecasting (WRF) simulations with different selections of subgrid orographic drag over the Tibetan Plateau have been evaluated with observation and ERA‐Interim reanalysis. Results show that the subgrid orographic drag schemes, especially the turbulent orographic form drag (TOFD) scheme, efficiently reduce the 10 m wind speed bias and RMS error with respect to station measurements. With the combination of gravity wave, flow blocking and TOFD schemes, wind speed is simulated more realistically than with the individual schemes only. Improvements are also seen in the 2 m air temperature and surface pressure. The gravity wave drag, flow blocking drag, and TOFD schemes combined have the smallest station mean bias (−2.05°C in 2 m air temperature and 1.27 hPa in surface pressure) and RMS error (3.59°C in 2 m air temperature and 2.37 hPa in surface pressure). Meanwhile, the TOFD scheme contributes more to the improvements than the gravity wave drag and flow blocking schemes. The improvements are more pronounced at low levels of the atmosphere than at high levels due to the stronger drag enhancement on the low‐level flow. The reduced near‐surface cold bias and high‐pressure bias over the Tibetan Plateau are the result of changes in the low‐level wind components associated with the geostrophic balance. The enhanced drag directly leads to weakened westerlies but also enhances the a‐geostrophic flow in this case reducing (enhancing) the northerlies (southerlies), which bring more warm air across the Himalaya Mountain ranges from South Asia (bring less cold air from the north) to the interior Tibetan Plateau.
Relict Mountain Permafrost Area (Loess Plateau, China) Exhibits High Ecosystem Respiration Rates and Accelerating Rates in Response to Warming
Authors: Mu Cuicui , Wu Xiaodong , Zhao Qian , Smoak Joseph M. , Yang Yulong , Hu Lian , Zhong Wen , Liu Guimin , Xu Haiyan , Zhang Tingjun 
Published: September 2017

AbstractRelict permafrost regions are characterized by thin permafrost and relatively high temperatures. Understanding the ecosystem respiration rate (ERR) and its relationship with soil hydrothermal conditions in these areas can provide knowledge regarding the permafrost carbon cycle in a warming world. In this study, we examined a permafrost area, a boundary area, and a seasonally frozen ground area within a relict permafrost region on the east edge of the Qinghai‐Tibetan Plateau, China. Measurements from July 2015 to September 2016 showed that the mean annual ecosystem CO2 emissions for the boundary area were greater than the permafrost area. The Q10 value of the ERRs in the seasonally frozen ground area was greater than the permafrost area, indicating that the carbon emissions in the nonpermafrost areas were more sensitive to warming. The 1 year open‐top chamber (OTC) warming increased soil temperatures in both the permafrost and seasonally frozen ground areas throughout the year, and the warming increased the ERRs by 1.18 (0.99–1.38, with interquartile range) and 1.13 (0.75–1.54, with interquartile range) μmol CO2 m−2 s−1 in permafrost and seasonally frozen ground areas, respectively. The OTC warming increased annual ERRs by approximately 50% for both permafrost and seasonally frozen ground areas with half the increase occurring during the nongrowing seasons. These results suggest that the ERRs in relict permafrost are high in comparison with arctic regions, and the carbon balance in relict permafrost areas could be greatly changed by climate warming.
Modeling Global Soil Carbon and Soil Microbial Carbon by Integrating Microbial Processes into the Ecosystem Process Model TRIPLEX‐GHG
Authors: Wang Kefeng , Peng Changhui , Zhu Qiuan , Zhou Xiaolu , Wang Meng , Zhang Kerou , Wang Gangsheng 
Published: September 2017

AbstractMicrobial physiology plays a critical role in the biogeochemical cycles of the Earth system. However, most traditional soil carbon models are lacking in terms of the representation of key microbial processes that control the soil carbon response to global climate change. In this study, the improved process‐based model TRIPLEX‐GHG was developed by coupling it with the new MEND (Microbial‐ENzyme‐mediated Decomposition) model to estimate total global soil organic carbon (SOC) and global soil microbial carbon. The new model (TRIPLEX‐MICROBE) shows considerable improvement over the previous version (TRIPLEX‐GHG) in simulating SOC. We estimated the global soil carbon stock to be approximately 1195 Pg C, with 348 Pg C located in the high northern latitudes, which is in good agreement with the well‐regarded Harmonized World Soil Database (HWSD) and the Northern Circumpolar Soil Carbon Database (NCSCD). We also estimated the global soil microbial carbon to be 21 Pg C, similar to the 23 Pg C estimated by Xu et al. (2014). We found that the microbial carbon quantity in the latitudinal direction showed reversions at approximately 30°N, near the equator and at 25°S. A sensitivity analysis suggested that the tundra ecosystem exhibited the highest sensitivity to a 1°C increase or decrease in temperature in terms of dissolved organic carbon (DOC), microbial biomass carbon (MBC), and mineral‐associated organic carbon (MOC). However, our work represents the first step toward a new generation of ecosystem process models capable of integrating key microbial processes into soil carbon cycles.
Are Model Transferability And Complexity Antithetical? Insights From Validation of a Variable‐Complexity Empirical Snow Model in Space and Time
Authors: Lute A. C. , Luce Charles H. 
Published: September 2017

AbstractThe related challenges of predictions in ungauged basins and predictions in ungauged climates point to the need to develop environmental models that are transferable across both space and time. Hydrologic modeling has historically focused on modelling one or only a few basins using highly parameterized conceptual or physically based models. However, model parameters and structures have been shown to change significantly when calibrated to new basins or time periods, suggesting that model complexity and model transferability may be antithetical. Empirical space‐for‐time models provide a framework within which to assess model transferability and any tradeoff with model complexity. Using 497 SNOTEL sites in the western U.S., we develop space‐for‐time models of April 1 SWE and Snow Residence Time based on mean winter temperature and cumulative winter precipitation. The transferability of the models to new conditions (in both space and time) is assessed using non‐random cross‐validation tests with consideration of the influence of model complexity on transferability. As others have noted, the algorithmic empirical models transfer best when minimal extrapolation in input variables is required. Temporal split‐sample validations use pseudoreplicated samples, resulting in the selection of overly complex models, which has implications for the design of hydrologic model validation tests. Finally, we show that low to moderate complexity models transfer most successfully to new conditions in space and time, providing empirical confirmation of the parsimony principal.
Simulating Small‐Scale Rainfall Fields Conditioned by Weather State and Elevation: A Data‐Driven Approach Based on Rainfall Radar Images
Authors: Oriani Fabio , Ohana‐Levi Noa , Marra Francesco , Straubhaar Julien , Mariethoz Gregoire , Renard Philippe , Karnieli Arnon , Morin Efrat 
Published: September 2017

AbstractThe quantification of spatial rainfall is critical for distributed hydrological modeling. Rainfall spatial patterns generated by similar weather conditions can be extremely diverse. This variability can have a significant impact on hydrological processes. Stochastic simulation allows generating multiple realizations of spatial rainfall or filling missing data. The simulated data can then be used as input for numerical models to study the uncertainty on hydrological forecasts. In this paper, we use the direct sampling technique to generate stochastic simulations of high‐resolution (1 km) daily rainfall fields, conditioned by elevation and weather state. The technique associates historical radar estimates to variables describing the daily weather conditions, such as the rainfall type and mean intensity, and selects radar images accordingly to form a conditional training image set of each day. Rainfall fields are then generated by resampling pixels from these images. The simulation at each location is conditioned by neighbor patterns of rainfall amount and elevation. The technique is tested on the simulation of daily rainfall amount for the eastern Mediterranean. The results show that it can generate realistic rainfall fields for different weather types, preserving the temporal weather pattern, the spatial features, and the complex relation with elevation. The concept of conditional training image provides added value to multiple‐point simulation techniques dealing with extremely nonstationary heterogeneities and extensive data sets.
The impact of a high‐definition multileaf collimator for spine SBRT
Authors: Younge Kelly C. , Kuchta John R. , Mikell Justin K. , Rosen Benjamin , Bredfeldt Jeremy S. , Matuszak Martha M. 
Published: September 2017

AbstractPurposeAdvanced radiotherapy delivery systems designed for high‐dose, high‐precision treatments often come equipped with high‐definition multi‐leaf collimators (HD‐MLC) aimed at more finely shaping radiation dose to the target. In this work, we study the effect of a high definition MLC on spine stereotactic body radiation therapy (SBRT) treatment plan quality and plan deliverability.Methods and MaterialsSeventeen spine SBRT cases were planned with VMAT using a standard definition MLC (M120), HD‐MLC, and HD‐MLC with an added objective to reduce monitor units (MU). M120 plans were converted into plans deliverable on an HD‐MLC using in‐house software. Plan quality and plan deliverability as measured by portal dosimetry were compared among the three types of plans.ResultsOnly minor differences were noted in plan quality between the M120 and HD‐MLC plans. Plans generated with the HD‐MLC tended to have better spinal cord sparing (3% reduction in maximum cord dose). HD‐MLC plans on average had 12% more MU and 55% greater modulation complexity as defined by an in‐house metric. HD‐MLC plans also had significantly degraded deliverability. Of the VMAT arcs measured, 94% had lower gamma passing metrics when using the HD‐MLC.ConclusionModest improvements in plan quality were noted when switching from M120 to HD‐MLC at the expense of significantly less accurate deliverability in some cases.
Organometal Trihalide Perovskites with Intriguing Ferroelectric and Piezoelectric Properties
Authors: Ding Ran , Zhang Xiaoli , Sun Xiao Wei 
Published: September 2017

AbstractOrganometal trihalide perovskites (OTPs) as a new subclass of perovskite materials have recently aroused increasing interest due to their numerous advantages of facile low‐temperature processing, tunable bandgaps, diverse compositions, and superior charge transfer dynamics, which have been widely used in various applications. In particular, solar cells composed of these perovskites have made unprecedented progress in just a few years with maximum power conversion efficiency, evolving from 3.8 to 21.6%. In spite of such impressive achievement, a fundamental understanding of intrinsic optoelectronic and physiochemical properties is a key challenge impeding the development of the OTPs. This review article aims to provide a concise overview of the current status of OTPs research, highlighting the unique properties of OTPs, especially ferroelectric and piezoelectric properties, which are vital to photovoltaic and piezoelectric applications but still not adequately explained. Various material synthesis strategies of OTPs are surveyed, exhibiting that the OTPs architecture can serve as a promising and robust platform for opening new horizons in ferroelectric and piezoelectric researches. Several applications, including piezoelectric generators, solar cells, light‐emitting diodes, lasers, photodetectors, and water‐splitting cells, demonstrate the latent potentialities of OTPs.
Multicolor Printing Using Electric‐Field‐Responsive and Photocurable Photonic Crystals
Authors: Chen Ke , Fu Qianqian , Ye Siyun , Ge Jianping 
Published: September 2017

AbstractEfficient and large scale printing of photonic crystal patterns with multicolor, multigrayscale, and fine resolution is highly desired due to its application in smart prints, sensors, and photonic devices. Here, an electric‐field‐assisted multicolor printing is reported based on electrically responsive and photocurable colloidal photonic crystal, which is prepared by supersaturation‐induced self‐assembly of SiO2 particles in the mixture of propylene carbonate (PC) and trimethylolpropane ethoxylate triacrylate (ETPTA). This colloidal crystal suspension, named as E‐ink, has tunable structural color, controllable grayscale, and instantly fixable characteristics at the same time because the SiO2/ETPTA‐PC photonic crystal has metastable and reversible assembly as well as polymerizable features. Lithographical printing with photomask and maskless pixel printing techniques are developed respectively to efficiently prepare multicolor and high‐resolution photonic patterns using a single‐component E‐ink.
Strategies for Optimizing the Soft Tissue Seal around Osseointegrated Implants
Authors: Abdallah Mohamed‐Nur , Badran Zahi , Ciobanu Ovidiu , Hamdan Nader , Tamimi Faleh 
Published: September 2017

AbstractPercutaneous and permucosal devices such as catheters, infusion pumps, orthopedic, and dental implants are commonly used in medical treatments. However, these useful devices breach the soft tissue barrier that protects the body from the outer environment, and thus increase bacterial infections resulting in morbidity and mortality. Such associated infections can be prevented if these devices are effectively integrated with the surrounding soft tissue, and thus creating a strong seal from the surrounding environment. However, so far, there are no percutaneous/permucosal medical devices able to prevent infection by achieving strong integration at the soft tissue–device interface. This review gives an insight into the current status of research into soft tissue–implant interface and the challenges associated with these interfaces. Biological soft/hard tissue interfaces may provide insights toward engineering better soft tissue interfaces around percutaneous devices. In this review, focus is put on the history and current findings as well as recent progress of the strategies aiming to develop a strong soft tissue seal around osseointegrated implants, such as orthopedic and dental implants.
Metal‐Ion‐Modified Black Phosphorus with Enhanced Stability and Transistor Performance
Authors: Guo Zhinan , Chen Si , Wang Zhongzheng , Yang Zhenyu , Liu Fei , Xu Yanhua , Wang Jiahong , Yi Ya , Zhang Han , Liao Lei , Chu Paul K. , Yu Xue‐Feng 
Published: September 2017

AbstractBlack phosphorus (BP), a burgeoning elemental 2D semiconductor, has aroused increasing scientific and technological interest, especially as a channel material in field‐effect transistors (FETs). However, the intrinsic instability of BP causes practical concern and the transistor performance must also be improved. Here, the use of metal‐ion modification to enhance both the stability and transistor performance of BP sheets is described. Ag+ spontaneously adsorbed on the BP surface via cation–π interactions passivates the lone‐pair electrons of P thereby rendering BP more stable in air. Consequently, the Ag+‐modified BP FET shows greatly enhanced hole mobility from 796 to 1666 cm2 V−1 s−1 and ON/OFF ratio from 5.9 × 104 to 2.6 × 106. The mechanisms pertaining to the enhanced stability and transistor performance are discussed and the strategy can be extended to other metal ions such as Fe3+, Mg2+, and Hg2+. Such stable and high‐performance BP transistors are crucial to electronic and optoelectronic devices. The stability and semiconducting properties of BP sheets can be enhanced tremendously by this novel strategy.
Coupling Diffusion Welding Technique and Mesh Screen Creates Heterogeneous Metal Surface for Droplets Array
Authors: Xie Jian , Xu Jinliang , Liu Qi , Li Xiang 
Published: September 2017

AbstractNonsilicon micromachining is a challenge, especially for large scale heterogeneous (hydrophilic/hydrophobic) surface fabrication. Here, mesh screen and diffusion welding technique are coupled to form a novel fabrication method. Mesh screen is used as mask. The diffusion welding technique sinters mesh screen on copper surface to form welding junction array. Chemical treatment of sintered package forms superhydrophobic nanostructures on surfaces except welding junction array. Separating mesh screen from copper substrate exposes hydrophilic dots array, corresponding to welding junction array. Thus, heterogeneous surface is created. By condensing wet air, main droplet and neighboring droplet occur on hydrophilic dot and superhydrophobic part, respectively. For horizontal surface, neighboring droplets initially generated on nanograsses behave consecutive events of coalescence, jump, and return, triggering contact/noncontact effect induced jumping. Thus, defect droplet area is formed and droplet size uniformity is broken. A nondimensional equation is proposed for the contact effect induced jumping analysis. Noncontact effect induced jumping is found for the first time. For vertical surface, droplet array behaves monodisperse size due to departure of merged neighboring droplets without returning, and equal opportunities of neighboring droplets captured by main droplets. The work opens a new way for large scale droplet array generation by controllable condensation.
Management of complicated diverticulitis of the colon
Authors: Tochigi Toru , Kosugi Chihiro , Shuto Kiyohiko , Mori Mikito , Hirano Atsushi , Koda Keiji 
Published: September 2017

AbstractDiverticular disease of the colon occurs quite frequently in developed countries, and its prevalence has recently increased in Japan. The appearance of diverticulosis increases with age, although mostly remaining asymptomatic. Approximately 20% of cases require treatment. As the Western lifestyle and number of elderly people increase, the need for medical treatment also increases. Computed tomography (CT) is the gold standard for diagnosing diverticulitis. Complicated diverticulitis is classified by the size and range of abscess formation and the severity of the peritonitis. Each case should be classified based on clinical and computed tomography (CT) findings and then treated appropriately. Most patients with uncomplicated diverticulitis (stages 0–Ia) can be treated conservatively. Diverticulitis with a localized abscess (stages Ib–II) is generally resolved with conservative treatment. If the abscess is larger or conservative treatment fails, however, percutaneous drainage or surgery should be considered. Operative treatment is considered standard therapy for severe diverticulitis with perforation and generalized peritonitis (stages III–IV). Colonic diverticulitis treated conservatively frequently recurs. Elective surgery after recovery should be considered carefully and decisions made on a case‐by‐case basis. Because cases of colonic diverticulitis will undoubtedly increase in Japan, it is likely that we will be confronted with increasing numbers of treatment decisions. We therefore need to have a systematic strategy for treating the various stages of colonic diverticulitis appropriately. We herein review the management of complicated diverticulitis.