bluuebunny/crossref_metadata_2025_split huggingface dataset:
Long‐term impacts of ocean wave‐dependent roughness on global climate systems
Authors: Shimura Tomoya , Mori Nobuhito , Takemi Tetsuya , Mizuta Ryo 
Published: February 2017

AbstractOcean surface waves can play an active role in climate systems, but they are often ignored in Global Climate Models (GCMs). Wave‐dependent surface roughness was implemented within the Atmospheric GCM (MRI‐AGCM) using the spectral wave model WAVEWATCH III. Two types of wave‐dependent roughness, due to wave steepness and to wave age, were considered. Climate simulations with wave‐dependent roughness were compared to simulations with just wind speed‐dependent roughness. In climate simulation with wave steepness‐dependent roughness, the spatial distribution of roughness is correlated to that of swell dominance. In simulation with wave age‐dependent roughness, the spatial distribution of roughness is correlated to that of wind direction stationarity. Both simulations show reduced roughness in the tropics, which leads to an enhancement of surface wind speeds by up to 15%; these enhanced wind speeds are closer to observations compared with the baseline simulation with just wind speed‐dependent roughness. We find that the reduced roughness and the enhanced wind speeds in the tropics lead to significant changes in atmospheric circulation, as in Hadley circulation and precipitation. The characteristic responses of the Hadley circulation and precipitation to changing sea surface roughness are presented.
Sensitivity of U.S. summer precipitation to model resolution and convective parameterizations across gray zone resolutions
Authors: Gao Yang , Leung L. Ruby , Zhao Chun , Hagos Samson 
Published: February 2017

AbstractSimulating summer precipitation is a significant challenge for climate models that rely on cumulus parameterizations to represent moist convection processes. Motivated by recent advances in computing that support very high‐resolution modeling, this study aims to systematically evaluate the effects of model resolution and convective parameterizations across the gray zone resolutions. Simulations using the Weather Research and Forecasting model were conducted at grid spacings of 36 km, 12 km, and 4 km for two summers over the conterminous U.S. The convection‐permitting simulations at 4 km grid spacing are most skillful in reproducing the observed precipitation spatial distributions and diurnal variability. Notable differences are found between simulations with the traditional Kain‐Fritsch (KF) and the scale‐aware Grell‐Freitas (GF) convection schemes, with the latter more skillful in capturing the nocturnal timing in the Great Plains and North American monsoon regions. The GF scheme also simulates a smoother transition from convective to large‐scale precipitation as resolution increases, resulting in reduced sensitivity to model resolution compared to the KF scheme. Nonhydrostatic dynamics has a positive impact on precipitation over complex terrain even at 12 km and 36 km grid spacings. With nudging of the winds toward observations, we show that the conspicuous warm biases in the Southern Great Plains are related to precipitation biases induced by large‐scale circulation biases, which are insensitive to model resolution. Overall, notable improvements in simulating summer rainfall and its diurnal variability through convection‐permitting modeling and scale‐aware parameterizations suggest promising venues for improving climate simulations of water cycle processes.
Electrical discharges in the overshooting tops of thunderstorms
Authors: MacGorman Donald R. , Elliott Matthew S. , DiGangi Elizabeth 
Published: February 2017

AbstractPrevious studies have found that the vertical distribution of sources of very high frequency (VHF) signals from discharges mapped by Lightning Mapping Arrays typically have a secondary maximum in a storm's overshooting top. Low rates of these sources tend to occur continually throughout the lifetime of the overshooting top (OT), rather than sources occurring in the episodic distinct flashes observed at lower altitudes. This study examines the evolution of the VHF OT signature (VHF OT, defined here as a sustained period of ≥4 VHF sources per minute per 200 m layer above a storm's level of neutral buoyancy (LNB)) relative to the evolution of radar reflectivity and IR imagery of overshooting tops in three supercell and two multicell storms. The VHF OT began before OTs were detected in IR satellite imagery of the supercell storms. No OT was observed in IR imagery for either multicell storm, but this lack may have been due to the spatial and temporal resolution of the current IR imager. The VHF OT began near the time the 18 or 30 dBZ echo top rose above the LNB and ended near the time it fell below the LNB. There were too few radar volume scans of OTs in the multicell storms for a correlation analysis. In the supercell storms, however, the maximum altitude of VHF sources typically was less than or equal to the altitude of 18 dBZ echo tops and was correlated with these echo tops (linear correlation coefficient ≥0.86) during the period of the VHF OT.
The occurrence of ice production in slightly supercooled Arctic stratiform clouds as observed by ground‐based remote sensors at the ARM NSA site
Authors: Zhang Damao , Wang Zhien , Luo Tao , Yin Yan , Flynn Connor 
Published: February 2017

AbstractIce particle formation in slightly supercooled stratiform clouds is not well documented or understood. In this study, 4 years of combined lidar depolarization and radar reflectivity (Ze) measurements are analyzed to distinguish between cold drizzle and ice crystal formations in slightly supercooled Arctic stratiform clouds over the Atmospheric Radiation Measurement Program Climate Research Facility North Slope of Alaska Utqiaġvik (“Barrow”) site. Ice particles are detected and statistically shown to be responsible for the strong precipitation in slightly supercooled Arctic stratiform clouds at cloud top temperatures as high as −4°C. For ice precipitating Arctic stratiform clouds, the lidar particulate linear depolarization ratio (δpar_lin) correlates well with radar Ze at each temperature range, but the δpar_lin‐Ze relationship varies with temperature ranges. In addition, lidar depolarization and radar Ze observations of ice generation characteristics in Arctic stratiform clouds are consistent with laboratory‐measured temperature‐dependent ice growth habits.
An efficient hybrid method for estimating clear‐sky surface downward longwave radiation from MODIS data
Authors: Cheng Jie , Liang Shunlin , Wang Wenhui , Guo Yamin 
Published: February 2017

AbstractThis paper proposes an efficient hybrid method for estimating 1 km instantaneous clear‐sky surface downward longwave radiation (LWDN) from Moderate Resolution Imaging Spectroradiometer (MODIS) thermal infrared observations and the MODIS near‐infrared column water vapor (CWV) data product. The LWDN was formulated as a nonlinear function of surface upwelling longwave radiation estimated from the MODIS top‐of‐atmosphere (TOA) radiance of channels 29, 31, and 32, as well as CWV and the MODIS TOA radiance of channel 29. Ground measurements collected at 62 globally distributed sites from six networks were used to develop and validate the proposed hybrid method. The validation results showed that the bias and root‐mean‐square error (RMSE) were 0.0597 W/m2 and 21.008 W/m2. These results demonstrate that the performance of our method is superior to that of other studies reported in the literature. The drawback of our method is that LWDN is overestimated over high‐elevation areas with extremely low CWV (<0.5 g/cm2) and underestimated over regions with tropical climates that have extremely high CWV. A power function relating LWDN to CWV was derived and used as a complementary method to address these circumstances. The overestimation was overcome, and the bias and RMSE decreased from 9.407 W/m2 and 23.919 W/m2 to −0.924 W/m2 and 19.895 W/m2. The underestimation was also alleviated.
Transient aspects of the Hadley circulation forced by an idealized off‐equatorial ITCZ
Authors: Gonzalez Alex O. , Mora Rojas Gabriela , Schubert Wayne H. , Taft Richard K. 
Published: February 2017

AbstractThis paper presents analytical solutions of large‐scale, zonally symmetric overturning circulations in the tropical free troposphere forced by transient diabatic heating in the off‐equatorial intertropical convergence zone (ITCZ). The dynamics are discussed in the context of the time‐dependent meridional circulation equation arising in an equatorial β‐plane model. The solutions of these differential equations contain terms for the slow, quasi‐balanced part of the response and terms for the transient, zonally symmetric, inertia‐gravity wave part of the response. When the off‐equatorial (north of the equator) ITCZ diabatic heating is switched on at various rates, both parts of the response reveal a basic asymmetry between the southern and northern hemispheres, with the southern hemisphere side containing most of the quasi‐balanced compensating subsidence and transient inertia‐gravity wave activity. The inertia‐gravity waves travel in wave packets that bounce off a spectrum of turning latitudes and are analyzed in the context of an average conservation law approach. These traveling wave packets cause the mass flux in the southern and northern Hadley cells to pulsate on timescales of about 1, 2, and 3 days for diabatic heating of the external, first internal, and second internal vertical modes, respectively. The spectral characteristics of the vertical motion in the ITCZ and subsidence regions are slightly more complicated and depend on ITCZ location.
“Sounds a Bit Crazy, But It Was Almost More Personal:” A Qualitative Study of Patient and Clinician Experiences of Physical Therapist–Prescribed Exercise For Knee Osteoarthritis Via Skype
Authors: Hinman R. S. , Nelligan R. K. , Bennell K. L. , Delany C. 
Published: February 2017

ObjectiveTo explore the experience of patients and physical therapists with Skype for exercise management of knee osteoarthritis (OA).MethodsThis was a qualitative study. The Donabedian model for quality assessment in health care (structure, process, and outcomes) informed semistructured individual interview questions. The study involved 12 purposively sampled patients with knee OA who received physical therapist–prescribed exercise over Skype, and all therapists (n = 8) who delivered the intervention in a clinical trial were interviewed about their experiences. Interviews were audio recorded and transcribed. Two investigators undertook coding and analysis using a thematic approach.ResultsSix themes arose from both patients and therapists. The themes were Structure: technology (easy to use, variable quality, set‐up assistance helpful) and patient convenience (time efficient, flexible, increased access); Process: empowerment to self‐manage (facilitated by home environment and therapists focusing on effective treatment) and positive therapeutic relationships (personal undivided attention from therapists, supportive friendly interactions); and Outcomes: satisfaction with care (satisfying, enjoyable, patients would recommend, therapists felt Skype more useful as adjunct to usual practice) and patient benefits (reduced pain, improved function, improved confidence and self‐efficacy). A seventh theme arose from therapists regarding process: adjusting routine treatment (need to modify habits, discomfort without hands‐on, supported by research environment).ConclusionPatients and physical therapists described mostly positive experiences using Skype as a service delivery model for physical therapist–supervised exercise management of moderate knee OA. Such a model is feasible and acceptable and has the potential to increase access to supervised exercise management for people with knee OA, either individually or in combination with traditional in‐clinic visits.
Serious Infection Rates Among Children With Systemic Lupus Erythematosus Enrolled in Medicaid
Authors: Hiraki Linda T. , Feldman Candace H. , Marty Francisco M. , Winkelmayer Wolfgang C. , Guan Hongshu , Costenbader Karen H. 
Published: February 2017

ObjectiveTo investigate the nationwide prevalence and incidence of serious infections among children with systemic lupus erythematosus (SLE) enrolled in Medicaid, the US health insurance program for low‐income patients.MethodsFrom Medicaid claims (2000–2006) we identified children ages 5 to <18 years with SLE (≥3 International Classification of Diseases, Ninth Revision [ICD‐9] codes of 710.0, each >30 days apart) and lupus nephritis (LN; ≥2 ICD‐9 codes for kidney disease on/after SLE codes). From hospital discharge diagnoses, we identified infection subtypes (bacterial, fungal, and viral). We calculated incidence rates (IRs) per 100 person‐years, mortality rates, and hazard ratios adjusted for sociodemographic factors, medications, and preventive care.ResultsAmong 3,500 children with identified SLE, 1,053 serious infections occurred over 10,108 person‐years; the IR was 10.42 per 100 person‐years (95% confidence interval [95% CI] 9.80–11.07) among all those with SLE and 17.65 per 100 person‐years (95% CI 16.29–19.09) among those with LN. Bacterial infections were most common (87%, of which 39% were bacterial pneumonias). In adjusted models, African Americans and American Indians had higher rates of infections compared with white children, and those with comorbidities or receiving corticosteroids had higher infection rates than those without. Males had lower rates of serious infections compared to females. The 30‐day postdischarge mortality rate was 4.4%.ConclusionOverall, hospitalized infections were very common in children with SLE, with bacterial pneumonia being the most common infection. Highest infection risks were among African American and American Indian children, those with LN, comorbidities, and those taking corticosteroids.
Determinants and outcomes of upfront surgery versus medical therapy for chronic rhinosinusitis in cystic fibrosis
Authors: Ayoub Noel , Thamboo Andrew , Habib Al‐Rahim , Nayak Jayakar V. , Hwang Peter H. 
Published: February 2017

BackgroundThe indications for surgical management of chronic rhinosinusitis (CRS) in patients with cystic fibrosis (CF) are poorly defined. In this study we compare outcomes of medical versus surgical treatment and examine trends associated with the transition from medical to surgical therapy in CF patients.MethodsOne hundred thirty‐six patients with CF referred to a tertiary rhinology practice were retrospectively divided into 3 cohorts: Medical, Upfront Surgery, or Crossover, if they converted from medical to surgical management. The 22‐item Sino‐Nasal Outcome Test (SNOT‐22) and pulmonary function test (PFT) data were assessed up to 48 months.ResultsCompared to patients initially managed medically (n = 90), those who pursued upfront surgery (n = 46) had a greater incidence of nasal polyposis (p = 0.0011), prior sinus surgery (p = 0.0025), lower percent‐predicted forced expiratory volume in 1 second (%FEV1) (p = 0.0063), and higher Lund‐Mackay (p = 0.0025) and SNOT‐22 (p = 0.0229) scores. Within the medical group, 35.5% converted to surgery after a mean of 14.3 months. Crossover (n = 32) was associated with a 6.1‐point increase in SNOT‐22 and a 4.5% deterioration in %FEV1. Despite worsened symptom severity, the Crossover cohort ultimately achieved similar postoperative SNOT‐22 scores (p = 0.831) and %FEV1 (p = 0.114) as those who underwent upfront surgery. Although the Medical cohort had the lowest baseline SNOT‐22 scores (p < 0.001), surgery at any time normalized scores to the same baseline level (p = 0.652). Neither medical therapy nor surgery improved PFTs.ConclusionsSurgery effectively reduces CRS‐related symptoms in CF patients but may not improve pulmonary function. In patients who first pursue medical therapy, symptomatic decline may prompt eventual conversion to surgery. Patients who delay surgery may achieve similar outcomes as those who pursue surgery upfront.
Active and recyclable ordered mesoporous magnetic organometallic catalyst as high‐performance visible light photocatalyst for degradation of organic pollutants
Authors: Nejat Razieh , Chamack Masoumeh , Mahjoub Alireza 
Published: February 2017

A novel light‐active magnetic Pd complex as a photocatalyst was prepared through bonding organometallics to mesoporous silica channels formed on the surface of silica‐coated iron oxide nanoparticles. The nanocomposite (denoted as Fe3O4@SiO2@m‐SiO2@PDA‐Pd(0); PDA = 1,10‐phenanthroline‐2,9‐dicarbaldehyde) is more efficient and has higher photocatalytic capability in the degradation of 2,4‐dichlorophenol under visible light irradiation compared with virgin Pd complex (PDA‐Pd). This noteworthy photodegradation activity can be due to the high dispersion of Pd nanoparticles. High yield, low reaction time and non‐toxicity of the catalyst are the main merits of this protocol. Also magnetic separation is an environmentally friendly alternative method for the separation and recovery of the catalyst, since it minimizes the use of solvents and auxiliary materials, reduces operation time and minimizes catalyst loss by preventing mass loss and oxidation. The produced Pd catalyst was characterised using various techniques. Furthermore, transmission electron microscopy characterization was used for determining the structural properties of the Pd nanocatalyst.
Thermo‐oxidative stabilization of poly(lactic acid)‐based nanocomposites through the incorporation of clay with in‐built antioxidant activity
Authors: Dintcheva Nadka Tzankova , Al‐Malaika Sahar , Morici Elisabetta , Arrigo Rossella 
Published: February 2017

ABSTRACTIn this work, an innovative approach to overcome the issue of the poor thermo‐oxidative stability of polymer/clay nanocomposites is proposed. Specifically, biodegradable poly(lactic acid) (PLA)‐based nanocomposites, containing organo‐modified clay with in‐built antioxidant activity, were prepared. Through a two‐step chemical protocol, a hindered phenol antioxidant was chemically linked to the ammonium quaternary salt which was then intercalated between the clay platelets [(AO)OM‐Mt]. The nanocomposites were characterized and their thermo‐oxidative stability during melt processing and under long‐term thermal test conditions was investigated. PLA nanocomposites containing the (AO)OM‐Mt showed higher oxidative stability, along with better clay dispersion, compared to PLA‐nanocomposites containing commercial clay and a free hindered phenol antioxidant. Obtained results can be explained considering that (AO)OM‐Mt may act locally, at the interface, between the silicate layers and the polymer macromolecules, thus contributing to the observed improved stability of the polymer both during processing and under long‐term thermal‐oxidative conditions. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44974.
Serum Urate Levels Predict Joint Space Narrowing in Non‐Gout Patients With Medial Knee Osteoarthritis
Authors: Krasnokutsky Svetlana , Oshinsky Charles , Attur Mukundan , Ma Sisi , Zhou Hua , Zheng Fangfei , Chen Meng , Patel Jyoti , Samuels Jonathan , Pike Virginia C. , Regatte Ravinder , Bencardino Jenny , Rybak Leon , Abramson Steven , Pillinger Michael H. 
Published: February 2017

ObjectiveThe pathogenesis of osteoarthritis (OA) includes both mechanical and inflammatory features. Studies have implicated synovial fluid uric acid (UA) as a potential OA biomarker, possibly reflecting chondrocyte damage. Whether serum UA levels reflect/contribute to OA is unknown. We investigated whether serum UA levels predict OA progression in a non‐gout knee OA population.MethodsEighty‐eight patients with medial knee OA (body mass index [BMI] <33 kg/m2) but without gout were studied. Baseline serum UA levels were measured in previously banked serum samples. At 0 and 24 months, patients underwent standardized weight‐bearing fixed‐flexion posteroanterior knee radiography to determine joint space width (JSW) and Kellgren/Lawrence grades. Joint space narrowing (JSN) was calculated as the change in JSW from 0 to 24 months. Twenty‐seven patients underwent baseline contrast‐enhanced 3T knee magnetic resonance imaging for assessment of synovial volume.ResultsSerum UA levels correlated with JSN values in both univariate (r = 0.40, P < 0.01) and multivariate (r = 0.28, P = 0.01) analyses. There was a significant difference in mean JSN after dichotomization at a serum UA cut point of 6.8 mg/dl, the solubility point for serum urate, even after adjustment (JSN of 0.90 mm for a serum UA ≥6.8 mg/dl and 0.31 mm for a serum UA <6.8 mg/dl; P < 0.01). Baseline serum UA levels distinguished progressors (JSN >0.2 mm) and fast progressors (JSN >0.5 mm) from nonprogressors (JSN ≤0.0 mm) in multivariate analyses (area under the receiver operating characteristic curve 0.63 [P = 0.03] and 0.62 [P = 0.05], respectively). Serum UA levels correlated with the synovial volume (r = 0.44, P < 0.01), a possible marker of JSN, although this correlation did not persist after controlling for age, sex, and BMI (r = 0.13, P = 0.56).ConclusionIn non‐gout patients with knee OA, the serum UA level predicted future JSN and may serve as a biomarker for OA progression.
Secukinumab in Active Rheumatoid Arthritis: A Phase III Randomized, Double‐Blind, Active Comparator– and Placebo‐Controlled Study
Authors: Blanco Francisco J. , Möricke Rüdiger , Dokoupilova Eva , Codding Christine , Neal Jeffrey , Andersson Mats , Rohrer Susanne , Richards Hanno 
Published: February 2017

ObjectiveTo evaluate the efficacy and safety of secukinumab in patients with active rheumatoid arthritis (RA) who had an inadequate response to or intolerance of tumor necrosis factor (TNF) inhibitors.MethodsIn this phase III study, 551 patients were randomized (1:1:1:1) to receive intravenous secukinumab at a dose of 10 mg/kg (at baseline and weeks 2 and 4) followed by subcutaneous secukinumab at a dose of either 150 mg or 75 mg every 4 weeks or, alternatively, abatacept or placebo on the same dosing schedule. The primary end point was the proportion of patients achieving 20% improvement in disease activity according to the American College of Rheumatology response criteria (ACR20) at week 24 in the secukinumab 150 mg or 75 mg treatment groups as compared with placebo. Key secondary end points included change from baseline to week 24 in the Disease Activity Score in 28 joints using C‐reactive protein level (DAS28‐CRP) and the Health Assessment Questionnaire disability index (HAQ DI), as well as the ACR 50% improvement (ACR50) response rate at week 24.ResultsThe primary efficacy end point was met in patients receiving 150 mg secukinumab, in whom the ACR20 response rate at week 24 was significantly higher than that in the placebo group. The ACR20 response rates at week 24 were 30.7% in patients receiving 150 mg secukinumab (P = 0.0305), 28.3% in those receiving 75 mg secukinumab (P = 0.0916), and 42.8% in those receiving abatacept, compared with 18.1% in the placebo group. A significant reduction in the DAS28‐CRP was seen in patients treated with 150 mg secukinumab (P = 0.0495), but not in patients treated with 75 mg secukinumab. Improvements in the HAQ DI and ACR50 response rates were not significant in the 2 secukinumab dose groups compared with the placebo group. The overall safety profile was similar across all treatment groups.ConclusionSecukinumab at a dose of 150 mg resulted in improvement in signs and symptoms and reduced disease activity in patients with active RA who had an inadequate response to TNF inhibitors. Improvements observed with abatacept were numerically higher than with secukinumab. There were no new or unexpected safety signals with secukinumab in this study.