bluuebunny/crossref_metadata_2025_split huggingface dataset:
Assessment of Factors Controlling Clumped Isotopes and δ18O Values of Hydrothermal Vent Calcites
Authors: Kluge Tobias , John Cédric M. , Boch Ronny , Kele Sándor 
Published: April 2018

AbstractThe clumped isotope composition of CaCO3 (Δ47) is a geochemical proxy that can provide mineral formation temperatures and, together with measured carbonate δ18O, inferred fluid δ18O values. Under natural conditions, carbonates form within a relatively wide pH range and varying growth rates which are typically not reflected in laboratory‐based calibrations (mostly ∼pH 8, moderate growth rates). A pH and growth‐rate dependence is known for oxygen isotopes and was also postulated for clumped isotopes. Theoretical predictions suggest that Δ47 values could lie between the carbonate equilibrium value and the value inherited from the dissolved inorganic carbon (predicted offset: +0.04‰ pH < 4 and −0.025‰ at high pH > 12). Here we test whether pH (in addition to temperature) is recorded in the carbonate clumped isotope composition using modern calcites from natural travertine‐forming streams and scales precipitated in pipes of deep geothermal wells from Italy, Hungary, and Turkey (pH: 6.1–7.5, T: 33–100°C). Although a comparison of all samples with expected equilibrium values in this pH range and known formation temperatures reveals only an insignificant Δ47 offset (0.006 ± 0.004‰, 1SE, n = 9), the clumped isotope values of samples with the highest growth rates (0.014 ± 0.007‰, 1SE, n = 5) are consistent with the theoretical prediction attributable to pH of 0.01‰. Similarly, deviations in δ18O of up to −2‰ follow a growth‐rate dependence. This field‐based study shows that pH‐related effects are mostly small for Δ47 in the subsurface environment at lower pH and that high mineral growth rates control the magnitude of this disequilibrium.
Influence of Sea Level Change and Centennial East Asian Monsoon Variations on Northern South China Sea Sediments Over the Past 36 kyr
Authors: Li Mingkun , Ouyang Tingping , Roberts Andrew P. , Heslop David , Zhu Zhaoyu , Zhao Xiang , Tian Chengjing , Peng Shasha , Zhong Hexian , Peng Xuechao , Qiu Yan 
Published: April 2018

AbstractSouth China Sea (SCS) sediments can provide important paleoclimate records because of their generally high deposition rates and strong regional influence of East Asian summer monsoon (EASM) variations. However, interpretation of sedimentary records from the northwestern SCS slope is complicated because sedimentation is sensitive to sea level and provenance variations. We seek to develop a paleoclimatic record of SCS sediments by analyzing sediment magnetic properties over the past ∼36 kyr from core PC338. The dominant magnetic minerals are magnetite and hematite in most parts of the core. The hematite concentration increased profoundly over the ∼15–32 kyr B.P. period when sea level was lower than −90 m below the present level. This suggests that Red River inputs were enhanced significantly in this period. Moreover, increased coarse magnetite contents were recorded in association with an enhanced East Asian winter monsoon (EAWM) during the Last Glacial Maximum and Heinrich event 1. Low‐field and frequency‐dependent magnetic susceptibility variations were coeval with EASM‐controlled climate change recorded in South China and the SCS over the past 15 kyr, probably because regional terrestrial weathering and erosion of iron‐bearing minerals, and their transportation are dominated by climate. Rhythmic coarsening of Holocene magnetic mineral concentrations coincided with global cooling events, which indicates that core PC338 also contains signals of enhanced EAWM variations. The study demonstrates that magnetic proxies are indicative of sediment supply and deposition variations on the SCS continental slope that are useful for understanding the effects of sea level and climate change on SCS sediments.
Understanding the Dominant Sources and Tracks of Moisture for Summer Rainfall in the Southwest United States
Authors: Jana Srijita , Rajagopalan Balaji , Alexander Michael A. , Ray Andrea J. 
Published: April 2018

AbstractWe investigated the moisture sources and tracks that enable summer rainfall over the four‐state southwestern U.S. region of Arizona, New Mexico, Colorado, and Utah by employing a high‐resolution Lagrangian particle tracking model. Six locations were selected—Cedar City (Utah), Grand Junction (Colorado), Eastonville (Colorado), Laveen (Arizona), Redrock (New Mexico), and Melrose (New Mexico)—together, they represent six spatial regions of summer precipitation for the Southwest. Moisture tracks were generated for all the rainy days at these stations for the historical period 1979–2013. Tracks were generated for a 3‐day period ending with the day of rainfall, which were then used to identify the source of moisture, pathway or trajectory, and the modulation along the track. The four major sources of moisture—Gulf of California, Gulf of Mexico (GoM), land, and the Pacific Ocean—were identified as responsible for summer rainfall over southwestern United States. The two dominant moisture sources at Laveen, Cedar City, Redrock, Grand Junction, and Eastonville were Gulf of California and land; at Melrose GoM and land were the dominant sources. The leading source of moisture at each location contributed to most of the extreme rainfall events. Tracks from GoM traveled the fastest and those from land sources were the slowest. Large‐scale circulation features–pressure, convergence, and specific humidity–were consistent with the moisture tracks and were found to be strong throughout the 3‐day period. This detailed and comprehensive generation of rainfall tracks offers unique insights into the moisture source and delivery for summer rainfall over southwestern United States.
Time‐Varying Storage–Water Age Relationships in a Catchment With a Mediterranean Climate
Authors: Rodriguez Nicolas B. , McGuire Kevin J. , Klaus Julian 
Published: April 2018

AbstractRecent studies on the relationships between catchment storage and water ages using Travel Time Distributions (TTDs), Residence Time Distributions (RTDs), and StorAge Selection (SAS) functions have led to the hypothesis that streamflow preferentially mobilizes younger water when catchment storage is high. This so‐called “Inverse Storage Effect” (ISE) needs further evaluation in more catchments with diverse climates and physiographical features. In this work, we assessed the validity of the ISE in WS10 (H. J. Andrews forest, Oregon, USA), a forested headwater catchment in a Mediterranean climate. A conceptual model of the catchment, developed based on experimental observations of water flow paths in WS10, was calibrated to streamflow and δ18O in streamflow. Based on the calibrated model results, we determined RTDs, and streamflow TTDs and SAS functions by assuming that the soil reservoir and the groundwater reservoir act as well‐mixed systems. The streamflow SAS functions and travel time dynamics showed that the ISE generally applies in WS10. Yet, during transitions from dry summer periods to wet winter periods and vice versa, the marked seasonal climate caused rapid and strong storage variations in the catchment, which led to deviations from the ISE. The seasonality of streamflow travel times in WS10 is the result of the seasonal contributions of younger water from the hillslopes added to the rather constant groundwater contributions of older water. The streamflow SAS functions were able to capture the relative importance of contrasting flow paths in the soils and in the bedrock highlighted by previous studies in WS10.
Sensitivity of Probable Maximum Flood in a Changing Environment
Authors: Gangrade Sudershan , Kao Shih‐Chieh , Naz Bibi S. , Rastogi Deeksha , Ashfaq Moetasim , Singh Nagendra , Preston Benjamin L. 
Published: April 2018

AbstractWith likely increases in probable maximum precipitation (PMP) in a changing environment, critical infrastructures such as major reservoirs and nuclear power plants are subject to elevated risk. To understand how factors such as PMP variability, climate change, land use land cover (LULC) change, antecedent soil moisture conditions, and reservoir storage may individually or jointly affect the magnitude of probable maximum flood (PMF), we conducted integrated hydrometeorological simulations involving both the Weather Research Forecasting model and the distributed hydrologic model (DHSVM) over the Alabama‐Coosa‐Tallapoosa (ACT) River Basin in the southeastern United States. A total of 120 relative humidity‐maximized PMP storms under historic and projected future climate conditions were used to drive DHSVM in current and projected future LULC conditions. Overall, PMP and PMF are projected to increase significantly over the ACT River Basin. Sources of meteorological forcing data sets and climate change were found to be the most sensitive factors affecting PMF, followed by antecedent soil moisture, reservoir storage, and then LULC change. The ensemble of PMP and PMF simulations, along with their sensitivity, allows us to better quantify the potential risks associated with hydroclimatic extreme events to critical infrastructures for energy‐water security.
Efficient Monte Carlo With Graph‐Based Subsurface Flow and Transport Models
Authors: O'Malley D. , Karra S. , Hyman J. D. , Viswanathan H. S. , Srinivasan G. 
Published: April 2018

AbstractSimulating flow and transport in fractured porous media frequently involves solving numerical discretizations of partial differential equations with a large number of degrees of freedom using discrete fracture network (DFN) models. Uncertainty in the properties of the fracture network that controls flow and transport requires a large number of DFN simulations to statistically describe quantities of interest. However, the computational cost of solving more than a few realizations of a large DFN can be intractable. As a means of circumventing this problem, we utilize both a high‐fidelity DFN model and a graph‐based model of flow and transport in combination with a multifidelity Monte Carlo (MC) method to reduce the number of high‐fidelity simulations that are needed to obtain an accurate estimate of the quantity of interest. We demonstrate the approach by estimating quantiles of the breakthrough time for a conservative tracer in an ensemble of fractured porous media. Our results demonstrate that a multifidelity MC estimate, whose computational cost is equal to the cost of 10 DFN simulations, can be as accurate as a standard MC estimate that utilizes 1,000 DFN simulations. Thus the combination of our graph‐based model with multifidelity MC estimates effectively reduces the computational cost of the problem by a factor of approximately 100.
Assessing New and Old Methods in Paleomagnetic Paleothermometry: A Test Case at Mt. St. Helens, USA
Authors: Bowles Julie A. , Gerzich Devin M. , Jackson Mike J. 
Published: April 2018

AbstractPaleomagnetic data can be used to estimate deposit temperatures (Tdep) of pyroclastic density currents (PDCs) by finding the laboratory temperature at which a PDC‐associated thermal remanence is removed. Paleomagnetic paleothermometry assumes that (1) blocking (Tb) and unblocking (Tub) temperatures are equivalent, and (2) the blocking spectrum remains constant through time. The first assumption fails for multidomain (MD) grains, and recent evidence shows that the second is violated in many titanomagnetites, where Tc is a strong function of thermal history. Here we assess the extent to which the standard paleomagnetic method may be biased by a changing Tb spectrum, and we explore a new magnetic technique that instead exploits these changes. Using samples from the 1980 PDCs at Mt. St. Helens, we find that standard methods on oriented lithic clasts provide a Tdep range that overlaps with measured temperatures, but is systematically slightly higher. By contrast, juvenile pumice give Tdep_min estimates that greatly exceed lithic estimates and measured temperatures. We attribute this overestimate to (1) depth‐dependent variations in Tc and Tub resulting from thermally activated crystal‐chemical reordering and (2) MD titanomagnetite where Tub > Tb. Stratigraphic variations in Tc are interpreted in terms of Tdep, giving results mostly consistent with measured temperatures and with the lower end of estimates from lithic clasts. This new method allows us to evaluate temporal and spatial variations in Tdep that would not have been possible using standard paleomagnetic techniques in these lithic‐poor deposits. It also provides information on deposits not accessible by surface temperature probes.
Vigilance detection method for high‐speed rail using wireless wearable EEG collection technology based on low‐rank matrix decomposition
Authors: Zhou Xiang , Yao Di , Zhu Miankuan , Zhang Xiaoliang , Qi Lingfei , Pan Hongye , Zhu Xin , Wang Yuan , Zhang Zutao 
Published: April 2018

With the development of rail transit, driver vigilance is increasingly important in railway safety. A vigilance detection method based on high‐speed rail (HSR) is presented in this study. The proposed method includes three main parts: (i) a wireless wearable electroencephalography (EEG) collection module; (ii) HSR driver's vigilance detection module; and (iii) an early warning module. Drivers’ vigilance is monitored using eight EEG channels. A low‐rank matrix decomposition (also called robust principal component analysis) algorithm is used to classify EEG signals which are collected through wireless wearable EEG collection technology. The warning module will sound an alarm and the early warning begins to message the train control centre if the driver is judged as fatigue. The method was tested on driving EEG data from ten different drivers and reached 99.4% correct classification in a 9 s time window. The feasibility of the proposed vigilance‐detecting method for HSR safety is demonstrated through simulation and test results.
Systematic clustering method to identify and characterise spatiotemporal congestion on freeway corridors
Authors: Ou Jishun , Yang Shu , Wu Yao‐Jan , An Chengchuan , Xia Jingxin 
Published: April 2018

Many analytical procedures, technical methods, and tools have been developed to facilitate manual inspection of traffic congestion and support the decision‐making process for traffic authorities. However, lacking an automatic mechanism, it would be a time‐consuming and labour‐intensive process for day‐to‐day and location‐by‐location analyses. This study presents a method based on a three‐stage framework that is capable of automatically identifying and characterising spatiotemporal congested areas (STCAs) by parsing, extracting, analysing and quantifying the knowledge contained in traffic heatmaps. The key components of the proposed method are two unsupervised clustering procedures: (i) a mini‐batch k ‐means clustering algorithm to separate the congested and non‐congested areas and (ii) a graph‐theory‐based clustering algorithm to distinguish between different STCAs. Twenty weekdays of dual loop detector data collected from a 26‐mile stretch of Interstate 10 in Phoenix, Arizona was analysed for the case study. The new method identified and quantified 102 STCAs without the need for human intervention. Based on 14 traffic measures calculated for each STCA, 19 active bottlenecks along the study corridor were identified. Top‐ranked bottlenecks identified in this study were consistent with those reported in previous studies but were produced with less effort, demonstrating the new method's potential utility for traffic congestion management systems.
Railway freight volume forecast using an ensemble model with optimised deep belief network
Authors: Feng Fenling , Li Wan , Jiang Qiwei 
Published: April 2018

Forecasting freight traffic contributes to the improvement of traffic facilities and making industrial policy, so it is significant to predict freight volume accurately. Extensive works had proved that ensemble model performed better than single model, so an ensemble model, combining seasonal autoregressive integrated moving average (SARIMA) with deep belief network (DBN), is proposed here. SARIMA, a linear model, is used to find the regularities of railway freight traffic. DBN, a non‐linear model, is taken to mine the complex relationships between indexes and railway freight. In order to decide appropriate architecture of DBN, including the number of network layers and neurons in each hidden layer, Gaussian particle swarm optimisation algorithm is designed to decide appropriate architecture of DBN, including the number of network layers and neurons in each hidden layer. Besides, Spearman rank correlation analysis is used for selecting indexes related to freight volume. Experimental results show that, compared with SARIMA, DBN, back propagation neural network, Elman neural network, and radial basis function neural network, the proposed ensemble model obtains best performance, and the mean absolute error is 5.5159 million t and the mean absolute percentage error is 1.9657%.
Numerical study of chip cooling with internal nanofluid in minichannels and external air flow over sink with laminar regimes
Authors: Esmaeilzadeh Kandjani Negar , Nurelahi Shahriyar , Tafrishi Seyed Amir , Esmaeilzadeh Esmaeil 
Published: April 2018

In this work, an electronic computer chip generates a 50– 150 W heat over a surface, requiring dissipation of about . The authors design a copper heat sink () that is mounted over the chip with two active methods for enhancing heat removal from the chip. To enhance the cooling effects, a laminar developing heat and fluid flow is introduced into the assumed seven miniature channels in a rectangular shape (), which takes away heat partly. Ethylene glycol as a base fluid and ethylene glycol + Al2O3 as a nanofluid with a volume fraction of nanoparticles 0.5, 1 and 1.5% flow with laminar regimes. To remove heat from the other parts of the sink, an external airflow is used with a free stream velocity of 2 m/s over it. This airflow is a laminar two‐dimensional boundary layer over the sink in the direction of its length. By numerical simulation, these two methods of cooling are investigated for enhancing heat removal from the sink. The results show cooling efficiency increased by about 8.5% in comparison with the cooling system with free convection where there is an internal cooling.
Preparation, properties and characterisation of microemulsion PCM slurry
Authors: Wang Dengwu , Si Jianlong , Ma Sude 
Published: April 2018

The provisions and applications of renewable energy have great supply–demand gap problem, and thermal energy storage (TES) is a very promising solution to fully utilise the renewable energy and covers off‐peak periods. The application of solid–liquid phase change material (PCM) is an effective way of TES based on the techniques of encapsulation and emulsion, but the capsules are easily broken and the emulsions are easily phase separated as they were phase changed for many times, so some other techniques should be developed. The microemulsion PCM slurry was prepared by the combination uses of emulsifiers (i.e. sorbitan monooleate 80 and polyoxyethylene sorbitan monooleate 80), coemulsifier (i.e. butanol), distilled water, purified paraffin and inorganic salts (i.e. potassium chloride). The average particle size in the slurry was about 50 nm, and the slurry was homogeneous after centrifugal acceleration of 1800g (i.e. ‘g’ is the gravity acceleration) for 5 min and phase change cycles for 1000 times. The latent heat of the slurry was 72.25 J g−1 and the paraffin content in the microemulsion was 43.8 wt %. The slurry can overcome the shortcomings of some other techniques and be expected to be widely applied in the TES.
Association Between Serum Infliximab Trough Concentrations During Maintenance Therapy and Biochemical, Endoscopic, and Histologic Remission in Crohn’s Disease
Authors: Papamichael Konstantinos , Rakowsky Shana , Rivera Claudio , Cheifetz Adam S , Osterman Mark T 
Published: April 2018

Abstract

Background and aim
Objective and more rigorous therapeutic outcomes are emerging as novel targets in Crohn’s disease (CD). We investigated the association between maintenance serum infliximab trough concentrations and biochemical, endoscopic, or histologic remission in CD.

Methods
This retrospective multicenter study involved consecutive CD patients treated with infliximab who had a serum C-reactive protein (CRP) measured within 1 week or endoscopic evaluation within 12 weeks of therapeutic drug monitoring between January 2010 and June 2016. Biochemical remission was defined as a normal CRP (≤5 mg/L). Endoscopic remission was defined as absence of any mucosal break (ulceration or erosion) or for patients with an ileocolonic resection, a Rutgeerts score of ≤i1. Histologic remission was defined as absence of active inflammation.

Results
Seventy-one CRP levels and 96 colonoscopies from 110 CD patients were evaluated. Based on ROC analyses, infliximab concentration thresholds of 2.2, 9.7, and 9.8 μg/mL were found to be related with biochemical, endoscopic, and histologic remission, respectively. Multiple logistic regression analyses identified infliximab concentration ≥2.2 (OR 6.4; 95% CI, 1.5–27.1; P = 0.011), ≥9.7 (OR 3.6; 95% CI, 1.4–9; P = 0.006) and ≥9.8 μg/mL (OR 3.2; 95% CI, 1.3–7.9; P = 0.011) as variables independently associated with biochemical, endoscopic, and histologic remission, respectively.

Conclusions
This study showed that higher maintenance infliximab trough concentrations are associated with more favorable rates of biochemical, endoscopic, or histologic remission in CD patients and that infliximab concentrations may differ based on the treatment goal.
Endoscopic Endonasal Transmaxillary Transsphenoidal Approach for Excision of a Superior Orbital Fissure-Cavernous Sinus Meningioma: 2-Dimensional Operative Video
Authors: El Refaee Ehab , Fleck Steffen , Matthes Marc , Schroeder Henry W S 
Published: April 2018

Abstract
We present a 43-old-male who suffered from a slowly progressive loss of vision in the left eye. Magnetic resonance (MR) imaging revealed a well-circumscribed contrast-enhancing lesion in the region of the anterior cavernous sinus and superior orbital fissure that extended into the optic canal. A schwannoma or meningioma was suspected. A transcranial surgery performed at another institution was not successful in removing the tumor and further deterioration of vision occurred. After resection of the left middle turbinate, the sphenoid and maxillary sinus were opened. The bulging of the tumor was seen at the lateral wall of the sphenoid sinus. After bony decompression of the optic canal, the dura was opened. A meningioma was exposed that arose in between the dural layers of the cavernous sinus. A nice dissection plane was found and the tumor was circumferentially dissected and finally totally removed. There were no complications such as double vision or visual field deficit. MR imaging confirmed a total tumor resection. The visual acuity normalized within a few days. MR imaging obtained 3 yr after surgery shows no recurrence.