bluuebunny/crossref_metadata_2025_split huggingface dataset:
Quantifying the Error of Radar-Estimated Refractivity by Multiple Elevation and Dual-Polarimetric Data
Authors: Feng Ya-Chien , Fabry Frédéric 
Published: August 2018

AbstractTo properly use radar refractivity data quantitatively, good knowledge of its errors is required. The data quality of refractivity critically depends on the phase measurements of ground targets that are used for the refractivity estimation. In this study, the observational error structure of refractivity is first estimated based on quantifying the uncertainties of phase measurements, data processing, and the refractivity estimation method. New correlations between the time series of phase measurements at different elevation angles and between polarizations are developed to assess the bulk phase variability of individual targets. Then, the observational error of refractivity is obtained by simulating the uncertainties of phase measurements through the original refractivity estimation method. Resulting errors in refractivity are found to be smaller than 1 N-unit in areas densely populated with reliable point-like stationary ground targets but grow as the target density becomes sparse.
Quantifying Highly Variable Air–Sea Momentum Flux Using Wavelet Analysis
Authors: Laxague Nathan J. M. , Haus Brian K. , Ortiz-Suslow David G. , Graber Hans C. 
Published: August 2018

AbstractSurface wind stress is a crucial driver of upper-ocean processes, impacting air–sea gas flux, wind-wave development, and material transport. Conventional eddy covariance (EC) processing requires imposing a fixed averaging window on the wind velocity time series in order to estimate the downward flux of momentum. While this method has become the standard means of directly measuring the wind stress, the use of a fixed averaging interval inherently constrains one’s ability to resolve transient signals that may have net effects on the air–sea interactions. Here we utilize the wavelet transform to develop a new technique for directly quantifying the wind stress magnitude from the wavelet coscalogram products. The time averages of these products evaluated at the scale of maximum amplitude are highly correlated with the EC estimates (R2 = 0.99; 5-min time windows), suggesting that stress is particularly sensitive to the dominant turbulent eddies. By taking advantage of the new method’s high temporal resolution, transient wind forcing and its dominant scales may be explicitly computed and analyzed. This technique will allow for more general investigations into air–sea dynamics under nonstationary or spatially inhomogeneous conditions, such as within the nearshore region.
2017 Atlantic Hurricane Forecasts from a High-Resolution Version of the GFDL fvGFS Model: Evaluation of Track, Intensity, and Structure
Authors: Hazelton Andrew T. , Bender Morris , Morin Matthew , Harris Lucas , Lin Shian-Jiann 
Published: August 2018

AbstractThe 2017 Atlantic hurricane season had several high-impact tropical cyclones (TCs), including multiple cases of rapid intensification (RI). A high-resolution nested version of the GFDL finite-volume dynamical core (FV3) with GFS physics (fvGFS) model (HifvGFS) was used to conduct hindcasts of all Atlantic TCs between 7 August and 15 October. HifvGFS showed promising track forecast performance, with similar error patterns and skill compared to the operational GFS and HWRF models. Some of the larger track forecast errors were associated with the erratic tracks of TCs Jose and Lee. A case study of Hurricane Maria found that although the track forecasts were generally skillful, a right-of-track bias was noted in some cases associated with initialization and prediction of ridging north of the storm. The intensity forecasts showed large improvement over the GFS and global fvGFS models but were somewhat less skillful than HWRF. The largest negative intensity forecast errors were associated with the RI of TCs Irma, Lee, and Maria, while the largest positive errors were found with recurving cases that were generally weakening. The structure forecasts were also compared with observations, and HifvGFS was found to generally have wind radii larger than the observations. Detailed examination of the forecasts of Hurricanes Harvey and Maria showed that HifvGFS was able to predict the structural evolution leading to RI in some cases but was not as skillful with other RI cases. One case study of Maria suggested that the inclusion of ocean coupling could significantly reduce the positive bias seen during and after recurvature.
Serum triglycerides predict first cardiovascular events in diabetic patients with hypercholesterolemia and retinopathy
Authors: Tada Hayato , Kawashiri Masa-aki , Nomura Akihiro , Yoshimura Kenichi , Itoh Hiroshi , Komuro Issei , Yamagishi Masakazu 
Published: August 2018

Aims Low-density lipoprotein cholesterol predicts cardiovascular events in patients with diabetes. However, it is uncertain whether serum triglycerides level is also associated with an occurrence of future cardiovascular events in diabetic patients. We aimed to test whether serum triglycerides is associated with first cardiovascular events in diabetic patients. Methods and results We recruited 5042 participants with diabetes mellitus from the standard versus intEnsive statin therapy for hypercholesteroleMic Patients with diAbetic retinopaTHY (EMPATHY), multicenter, prospective, randomized, open-label, blinded-endpoint study. Median follow-up was three years. We evaluated an association of serum triglycerides with first cardiovascular events in cox-regression hazard models adjusted by age, sex, hypertension, current smoking, low-density lipoprotein cholesterol, and body mass index. Cardiovascular events were defined as (a) major adverse cardiac events including myocardial infarction, stroke, or cardiac death; and (b) cardiovascular diseases including myocardial infarction, unstable angina, ischemic stroke, or large artery disease or peripheral arterial disease. Serum triglycerides were associated with major adverse cardiac events (adjusted hazard ratio: 1.021 per 10 mg/dl; 95% confidence interval: 1.007–1.035; p = 0.0025) and cardiovascular diseases (adjusted hazard ratio: 1.023 per 10 mg/dl; 95% confidence interval: 1.013–1.034; p = 0.0000077). Comparing the top quintile (>185 mg/dl) with the bottom quintile (<79 mg/dl), the adjusted hazard ratio increased 1.89 (95% confidence interval: 1.03–2.80, p = 0.04) for major adverse cardiac events, and 1.90 (95% confidence interval: 1.18–3.07, p = 0.007) for cardiovascular diseases. There were no overall interactions of triglycerides and treatment assignment (standard/intensive statins) on both outcomes ( p-trend = 0.33 for major adverse cardiac events, p-trend = 0.62 for cardiovascular diseases). Conclusions Serum triglycerides were associated with first cardiovascular events among high-risk diabetes patients with hypercholesterolemia and retinopathy.
Mediating Effect of Muscle on the Relationship of Physical Activity and Bone
Authors: ZYMBAL VERA , BAPTISTA FÁTIMA , LETUCHY ELENA M. , JANZ KATHLEEN F. , LEVY STEVEN M. 
Published: August 2018

ABSTRACT

Purpose
This study analyzed prospective associations between distinct trajectories of objectively measured physical activity (PA) and late adolescent bone parameters and explored the mediating effects of lean soft tissue, a surrogate of muscle mass to associations.

Methods
Physical activity was measured by accelerometry starting at age 5 yr and continuing at 8, 11, 13, 15, and 17 yr in approximately 524 participants from the Iowa Bone Development Study. Sex-specific group-based trajectory modeling was used to construct developmental trajectories of moderate- and vigorous-intensity PA (MVPA) from childhood to late adolescence. At age 17 yr, proximal femur bone mineral density (aBMD) was assessed by dual X-ray energy absorptiometry, and its distribution was calculated by aBMD ratios. Specific geometric measures of the proximal femur were assessed using hip structural analysis.

Results
A significant portion of the total effect of MVPA from age 5 to 17 yr on bone parameters at age 17 yr was explained by an increase in leg lean soft tissue in both sexes. For males and females, indirect effects were observed on the total and all regional proximal femur aBMD, and on the ratio between the inferomedial and superolateral neck aBMD. The effect on the ratio between the trochanter and the total proximal femur was specific to females, whereas the effect on the hip axis length was specific to males. Direct effects of MVPA on aBMD were identified only in males.

Conclusions
Using robust mediation analysis, this is the first study addressing the indirect effect (through muscle) of PA across childhood and adolescence on proximal femur bone parameters. To improve bone health at the proximal femur, the results suggest PA interventions during growth that increase muscle mass, particularly in females.
Critical Velocity during Intermittent Running with Changes of Direction
Authors: KIRBY BRETT S. , BRADLEY ERIC M. , WILKINS BRAD W. 
Published: August 2018

ABSTRACT

Purpose
We tested the hypothesis that critical velocity (CV) during intermittent running with changes of direction is reliably and accurately identified from a simple shuttle field test. We also tested the hypothesis that CV during intermittent running with changes of direction running is not equivalent to continuous linear running.

Methods
Young adults performed a custom shuttle test of intermittent sprint running to reveal CV. Sprints were 18.3 m per direction, with rest between sprints of 15 s for 3 min, 10 s for 2 min, and no rest for 2 min (7 min total). To test reliability, the CV shuttle test (CVST) was performed twice. To test validity, blood lactate was assessed during two separate trials inclusive of 5% above or below CVST end velocity. To explore task specificity, CV during CVST was compared to CV obtained from three linear running time trials.

Results
Total distance and CSVT end test velocity were similar between visits (864 ± 21 m and 3.23 ± 0.13 m·s−1 vs 900 ± 30 m and 3.21 ± 0.15 m·s−1, respectively). At 5% above CVST end velocity, all subjects failed to complete 20 min and had unstable blood lactate values. A steady state blood lactate profile was observed during trials 5% below end velocity and all subjects completed the trial. The CV from the CVST was lower than the CV from linear running (△ −17% ± 6%), highlighting the importance of test specificity for threshold determination.

Conclusions
The CVST provides a reliable and accurate determination of CV and can be used by coaches, athletes, and trainers to better understand the physiological impact specific to practice or competitions involving intermittent change of direction running.
Adverse childhood experiences in the children of the Avon Longitudinal Study of Parents and Children (ALSPAC)
Authors: Houtepen Lotte C. , Heron Jon , Suderman Matthew J. , Tilling Kate , Howe Laura D. 
Published: August 2018

Background: Exposure to adverse childhood experiences (ACEs) is a risk factor for poor later life health. Here, we describe the ACE variables measured in the children of the Avon Longitudinal Study of Parents and Children (ALSPAC) study, and a method used to derive summary measures and deal with missing data in them. Methods: The ALSPAC data catalogue (59 608 variables) was searched in September 2017 for measures on adversity exposure between birth and 18 years. 6140 adversity questions were then screened for conforming to our ACE definitions and suitability for dichotomisation. This screening identified 541 questions on ten ‘classic’ ACEs (sexual, physical or emotional abuse, emotional neglect, substance abuse by the parents, parental mental illness or suicide attempt, violence between parents, parental separation, bullying and parental criminal conviction) and nine additional ACEs (bond between parent and child, satisfaction with neighbourhood, social support for the parent, social support for the child, physical illness of a parent, physical illness of the child, financial difficulties, low social class and violence between child and partner). These were used to derive a binary construct for exposure to each ACE. Finally, as cumulative measures of childhood adversity, different combinations of the 19 ACE constructs were summed to give total adversity scores. An appropriate strategy for multiple imputation was developed to deal with the complex patterns of missing data. Results: The ACE constructs and ACE-scores for exposure between birth and 16 years had prevalence estimates that were comparable to previous reports (for instance 4% sexual abuse, 18% physical abuse, 25% bullied, 32% parental separation). Conclusions: ACE constructs, derived using a pragmatic approach to handle the high dimensional ALSPAC data, can be used in future analyses on childhood adversity in ALSPAC children.
Parallel Connection and Sandwich Electrodes Lower the Internal Resistance in a Microbial Fuel Cell
Authors: Ortega-Martínez Areli , Juárez-López Katy , Solorza-Feria Omar , Ponce-Noyola María T. , Ríos-Leal Elvira , Rinderknecht-Seijas Noemí F. , Poggi-Varaldo Héctor M. 
Published: August 2018

The aim of this work was to design and characterize a novel, multiface parallelepiped MFC in the perspective of decreasing the internal resistance (Rint) and increasing the volumetric power (Pv) output. The cell was fitted with a ‘sandwich’ cathode-membrane-anode assemblage in five of its faces, and possessed a ratio electrode surface area-to-volume ξ (csi) of 19 m-1 .
When the 5 faces of the MFC-P were connected in series, the Rint was 601 Ω with a voltage of 0.52 V. Characterization of the cell with the 5 faces connected in parallel gave a Rint of 62 Ω with a voltage of 0.5 V that corresponded to external resistance of 56 k Ω in the polarization procedure. This result was ascribed to both the changes in cell architecture and decrease of the inter-electrode distance as well as the parallel connection. The Pv of the new MFC-P achieved values of 62 and 570 mW/m3 for series and parallel connection, respectively.
Molecular ecological techniques were used to analyze the bacterial diversity of biocatalyst used in new design MFC-P. They showed a low species richness and low-to-moderate evenness. The community consisted primarily of δ-Proteobacteria and Firmicutes, bacteria that are recognized to be capable of exocellular electron transfer.
A Heavy Load Optimized Dynamic Bandwidth Allocation Algorithm for Hybrid WDM/TDM VPONs
Authors: Singhal Ankur , Gupta Amit , Singh Charanjeet 
Published: August 2018

Abstract
Hybrid wavelength division multiplexed (WDM)/Time division multiplexed (TDM) virtual passive optical networks (VPONs) are considered to provide cost efficient solutions for ever increasing bandwidth requirements of next generation optical access networks. With the development in technology effective bandwidth assignment has emerged as a major concern area. In this paper a novel heavy load optimized dynamic bandwidth allocation algorithm (HLO-DBA) is proposed for the hybrid WDM/TDM VPONs. Multi point control protocol of Ethernet passive optical network (EPON) is implemented for WDM/TDM VPONs subscribers. The excess bandwidth of lightly loaded subscribers is distributed among heavily loaded users through an efficient mechanism. The proposed technique effectively utilize the idle period between the last transmitted REPORT messages from previous transmission cycle (t-1) to the first GRANT message in the current cycle (t). Optical network units (ONUs) connecting the subscribers are scheduled in such a way so as to reduce the wastage of bandwidth. Performance evaluation of HLO-DBA in terms of quality of service (QOS) metrics like throughput and average delay is done to validate the optimization of the proposed mechanism.
Calibration Experiment for Seepage Monitoring Using Fiber Bragg Grating Hydrothermal Cycling Integration System
Authors: Chen Jiang , Xiong Feng , Zheng Junli , Ge Qi , Cheng Fei 
Published: August 2018

Abstract
Seepage monitoring is an important element in geotechnical engineering. This article proposed a new integrated system for seepage monitoring composed of a fiber Bragg grating (FBG) sensing system and a water-heating cycling system. The boiler is used as the heating equipment in the integrated system. The heated water is distributed to each heating pipeline for cyclic heating through the water separator and water collector. The FBG temperature sensors are preburied in the heating pipeline to monitor the water temperature in real time. Recognizing the correlation between the temperature field and the seepage field, we proposed to fit coefficient ξv according to the cooling curve and used it as an index to identify the seepage state. We conducted this numerical simulation to analyze the heat transfer process of the heat source in the porous media. We carried out the calibration experiments of seepage velocity using the FBG-sensing heating system in the porous medium with four different gradations. Our results showed that the temperature gradient decreased over time, indicating that the primary way the heat source was transferred was through the convective heat transfer caused by the seepage. Therefore, the coefficient ξv could be used as the seepage identification index. On the basis of our calibration experiments, we obtained the fitting formulas of ξv and the seepage velocity in four kinds of porous mediums. The formulas can be used for the inversion of seepage velocity. The experimental results proved that ξv was unrelated to the initial cooling temperature. This finding showed that the influence of an uneven temperature distribution along the heating pipeline on monitoring results could be ignored.
CARACTERÍSTICAS HIDROGRÁFICAS DEL SISTEMA LAGUNAR LOS MICOS-QUEMADA EN EL CARIBE HONDUREÑO
Authors: Brenes Carlos L. , Benavides Morera Rosario , Ballestero Daniel 
Published: August 2018

Auspiciado por el Proyecto PREPAC (Plan Regional de Pesca y Acuicultura Continental) se realizó un levantamiento hidrográfico en 27 estaciones en el sistema lagunar Micos-Quemada en el litoral Caribe de Honduras. Los muestreos mensuales se extendieron de octubre del 2005 a mayo del 2006 y se determinaron la temperatura, el pH, el oxígeno disuelto, la salinidad y la turbidez. La temperatura superficial osciló entre los 24.2 y 31.8°C, con variaciones temporales extremas del orden de los 7°C. Lo valores más bajos se ubican al final y principio de año (octubre-febrero). La salinidad superficial presenta un marcado ciclo estacional, con valores superiores a 12 durante los meses secos en prácticamente todo el cuerpo de agua, mientras que en la época lluviosa (octubre a febrero) están alrededor de 6. Los valores de pH encontrados para el período de estudio se ubicaron entre los 7.8 y 8.7. Los valores más altos se localizan en la zona central del sistema lagunar y los más bajos en las zonas cercanas a las orillas. Los máximos valores de turbidez se observan en febrero y diciembre. La zona con aguas más claras se localiza en la región cercana a la Barra de Miami en el lado noroeste de la laguna. El oxígeno superficial varió entre 5.0 mg/L y 7.6 mg/L durante los meses de octubre a febrero. La variación temporal del oxígeno disuelto muestra que los máximos y mínimos para todo el período de estudio se localizaron en octubre y mayo respectivamente. A hydrographic survey funded by PREPAC (Plan Regional de Pesca y Acuicultura Continental) was carried out in the Micos-Quemada lagoon system in the Caribbean coast of Honduras. From October 2005 to May 2006 27 sampling stations were occupied to measure pH, dissolved oxygen, salinity, and turbidity. Surface temperatures were between 24.2 and 31.8°C during the sampling period, with extreme temporal variations close to 7°C. Minimum temperatures were observed between October and February. Surface salinity showed a clear seasonal cycle, with values greater than 12 during the dry months virtually over the entire body of water, while during the rainy season (October to February) salinity values were around 6. Values for pH were between 7.8 and 8.7 during the study. The highest pH values were found in the central area of the lagoon system and the lowest in the areas close to the banks, likely due to the degradation of organic matter and to the contribution from the tributary. Maximum turbidity was observed in February and December, while the area with clearest water was located near the bar. Surface oxygen concentration varied between 5.0 and 7.6 mg/L from October to February. Maximum and minimum values of dissolved oxygen were observed in October and May, respectively.
PATTERNS OF PREY BIOMASS CONSUMPTION BY SMALL ODONTOCETES IN THE NORTHEASTERN COAST OF VENEZUELA
Authors: Oviedo Correa Lenin E. 
Published: August 2018

Trophic relationships are conditioned by population dynamics of interacting species in the community (species present, food web connections among them, and the strength of interactions), and on the consequences of these species interactions depend various ecosystem processes such as productivity and nutrient flux. Odontocetes target a wide range of prey items and are adapted to feeding at different depths. The aim of this report is to describe the patterns of prey consumption by small odontocetes, incorporating natural predatory patterns into a potential management scheme of strategic food sources, for both human and marine predators. Using the geo-statistical analysis tool of ArcGIS 9.2, maps illustrating the intensity and location of prey consumption were made for species with a sighting index (SPUE) > 0.15. The biomass consumption emphasized the differences in habitat use by species. The trends in distribution of prey biomass removal by odontocetes particularly suggest a stratification of prey consumption primarily in shelf waters, with a prey biomass that is comprised basically by demersal fish and small pelagics (including Sardinella aurita), and into transition-oceanic depths where most of the predatory pattern would potentially rely on pelagic - mesopelagic squid and myctophids. Overall the spatial tendencies in regionalization presented in this contribution will serve as a base-line to assess ecosystem health and evaluate management scenarios. Las relaciones tróficas son reguladas por la dinámica poblacional de las especies que interactúan dentro de la comunidad (especies presentes, conexiones interespecíficas, y nivel de interacción) y de las consecuencias de esas interacciones para procesos del ecosistema como la productividad y el flujo de nutrientes. El objetivo de este reporte es evaluar el patrón de consumo de biomasa por odontocetos de menor tamaño en la costa Nororiental de Venezuela, incorporando patrones de depredación natural a un esquema potencial de manejo de un recurso alimentario estratégico. Por medio de la herramienta de análisis geoestadístico del software ArcGIS 9.2, se elaboraron mapas de densidad en consumo de biomasa de presas para las especies con un índice de avistamiento (SPUE) > 0.15. El consumo de biomasa de presas enfatiza en el uso diferencial de hábitat por especie. La tendencia en la distribución de la remoción de biomasa de presas por cetáceos odontocetos principalmente sugiere la estratificación del habitat, primeramente en el ámbito de la plataforma continental, con un biomasa de presas que estaría constituida por peces demersales y pequeños pelágicos (entre estos S. aurita). Así como en profundidades Transicionales - Oceánicas, donde la mayoría de los patrones de depredación dependerían de organismos pelágicos - mesopelágicos, como calamares y peces mictófidos. Las tendencias espaciales en regionalización, como las que se presentan en es reporte, representan una línea base clave para evaluar la salud de los ecosistemas y escenarios de manejo.