bluuebunny/crossref_metadata_2025_split huggingface dataset:
Efficiency of high‐performance discontinuous Galerkin spectral element methods for under‐resolved turbulent incompressible flows
Authors: Fehn Niklas , Wall Wolfgang A. , Kronbichler Martin 
Published: May 2018

SummaryThe present paper addresses the numerical solution of turbulent flows with high‐order discontinuous Galerkin methods for discretizing the incompressible Navier‐Stokes equations. The efficiency of high‐order methods when applied to under‐resolved problems is an open issue in the literature. This topic is carefully investigated in the present work by the example of the three‐dimensional Taylor‐Green vortex problem. Our implementation is based on a generic high‐performance framework for matrix‐free evaluation of finite element operators with one of the best realizations currently known. We present a methodology to systematically analyze the efficiency of the incompressible Navier‐Stokes solver for high polynomial degrees. Due to the absence of optimal rates of convergence in the under‐resolved regime, our results reveal that demonstrating improved efficiency of high‐order methods is a challenging task and that optimal computational complexity of solvers and preconditioners as well as matrix‐free implementations are necessary ingredients in achieving the goal of better solution quality at the same computational costs already for a geometrically simple problem such as the Taylor‐Green vortex. Although the analysis is performed for a Cartesian geometry, our approach is generic and can be applied to arbitrary geometries. We present excellent performance numbers on modern cache‐based computer architectures achieving a throughput for operator evaluation of 3·108 up to 1·109 DoFs/s (degrees of freedom per second) on one Intel Haswell node with 28 cores. Compared to performance results published within the last five years for high‐order discontinuous Galerkin discretizations of the compressible Navier‐Stokes equations, our approach reduces computational costs by more than one order of magnitude for the same setup.
HIV‐1Tat regulation of dopamine transmission and microglial reactivity is brain region specific
Authors: Miller Douglas R. , Shaerzadeh Fatemeh , Phan Leah , Sharif Nesrin , Gamble‐George Joyonna , McLaughlin Jay P. , Streit Wolfgang J. , Khoshbouei Habibeh 
Published: May 2018

AbstractThe transactivator of transcription protein, HIV‐1 Tat, is linked to neuroAIDS, where degeneration of dopamine neurons occurs. Using a mouse model expressing GFAP‐driven Tat protein under doxycycline (Dox) regulation, we investigated microglial‐neuronal interactions in the rostral substantia nigra pars compacta (SNc). Immunohistochemistry for microglia and tyrosine hydroxylase (TH) showed that the ratio of microglia to dopamine neurons is smaller in the SNc than in the ventral tegmental area (VTA) and that this difference is maintained following 7‐day Dox exposure in wild type animals. Administration of Dox to wild types had no effect on microglial densities. In addressing the sensitivity of neurons to potentially adverse effects of HIV‐1 Tat, we found that HIV‐1 Tat exposurein vivoselectively decreased TH immunoreactivity in the SNc but not in the VTA, while levels of TH mRNA in the SNc remained unchanged. HIV‐1 Tat inductionin vivodid not alter the total number of neurons in these brain regions. Application of Tat (5 ng) into dopamine neurons with whole‐cell patch pipette decreased spontaneous firing activity. Tat induction also produced a decline in microglial cell numbers, but no microglial activation. Thus, disappearance of dopaminergic phenotype is due to a loss of TH immunoreactivity rather than to neuronal death, which would have triggered microglial activation. We conclude that adverse effects of HIV‐1 Tat produce a hypodopamine state by decreasing TH immunoreactivity and firing activity of dopamine neurons. Reduced microglial numbers after Tat exposurein vivosuggest impaired microglial functions and altered bidirectional interactions between dopamine neurons and microglia.
Sox2 conditional mutation in mouse causes ataxic symptoms, cerebellar vermis hypoplasia, and postnatal defects of Bergmann glia
Authors: Cerrato Valentina , Mercurio Sara , Leto Ketty , Fucà Elisa , Hoxha Eriola , Bottes Sara , Pagin Miriam , Milanese Marco , Ngan Chew‐Yee , Concina Giulia , Ottolenghi Sergio , Wei Chia‐Lin , Bonanno Giambattista , Pavesi Giulio , Tempia Filippo , Buffo Annalisa , Nicolis Silvia K. 
Published: May 2018

AbstractSox2 is a transcription factor active in the nervous system, within different cell types, ranging from radial glia neural stem cells to a few specific types of differentiated glia and neurons. Mutations in the human SOX2 transcription factor gene cause various central nervous system (CNS) abnormalities, involving hippocampus and eye defects, as well as ataxia. Conditional Sox2 mutation in mouse, with different Cre transgenes, previously recapitulated different essential features of the disease, such as hippocampus and eye defects. In the cerebellum, Sox2 is active from early embryogenesis in the neural progenitors of the cerebellar primordium; Sox2 expression is maintained, postnatally, within Bergmann glia (BG), a differentiated cell type essential for Purkinje neurons functionality and correct motor control. By performing Sox2 Cre‐mediated ablation in the developing and postnatal mouse cerebellum, we reproduced ataxia features. Embryonic Sox2 deletion (with Wnt1Cre) leads to reduction of the cerebellar vermis, known to be commonly related to ataxia, preceded by deregulation of Otx2 and Gbx2, critical regulators of vermis development. Postnatally, BG is progressively disorganized, mislocalized, and reduced in mutants. Sox2 postnatal deletion, specifically induced in glia (with GLAST‐CreERT2), reproduces the BG defect, and causes (milder) ataxic features. Our results define a role for Sox2 in cerebellar function and development, and identify a functional requirement for Sox2 within postnatal BG, of potential relevance for ataxia in mouse mutants, and in human patients.
Incompletely treated malignancies of the major salivary gland: Toward evidence‐based care
Authors: Tam Samantha , Sandulache Vlad C. , Metwalli Kareem A. , Rock Crosby D. , Eraj Salman A. , Sheu Tommy , El‐Naggar Adel K. , Fuller Clifton D. , Weber Randal S. , Lai Stephen Y. 
Published: May 2018

AbstractBackgroundUnexpected malignancy is common in major salivary gland tumors due to variability of workup, creating challenging treatment decisions. The purpose of this study was to define treatment‐related outcomes for patients with incompletely treated major salivary gland tumors.MethodsA retrospective cohort study was completed of patients with incompletely treated major salivary gland tumors. Tumor burden at presentation was established and treatment categorized. The Cox Proportional Hazards model was used to determine predictors of survival and failure.ResultsOf the 440 included patients, patients with gross residual or metastatic disease had a worse overall survival (OS; P < .001). Presentation status was an independent predictor of OS on multivariate analysis (gross residual disease adjusted hazard ratio [HRadjusted] 2.55; 95% confidence interval [CI] 1.20‐5.30; metastatic disease HRadjusted 9.53; 95% CI 3.04‐27.06).ConclusionFailure to achieve gross total resection during initial surgery resulted in worse OS. Adequate preoperative planning is required for initial surgical management to optimize tumor control and survival.
Comparison of tumor volume, thickness, and T classification as predictors of outcomes in surgically treated squamous cell carcinoma of the oral tongue
Authors: Mair Manish , Nair Deepa , Nair Sudhir , Malik Akshat , Mishra Aseem , Kannan Sadhana , Bobdey Saurabh , Singhvi Hitesh , Chaturvedi Pankaj 
Published: May 2018

AbstractBackgroundAs per TNM classification, superficial tumors with a favorable prognosis are fallaciously clubbed together with unfavorable, deeply infiltrating lesions in the same classification.MethodsThis is a retrospective study of 588 patients with treatment‐naive oral tongue cancers. Binary logistic regression was used to identify predictors of nodal metastasis and extracapsular spread (ECS) using tumor volume and thickness as separate models. The C‐index was generated to quantify predictive accuracy of T classification, thickness, and tumor volume for survival.ResultsCompared to T classification, tumor volume and thickness were better predictors of nodal metastasis and ECS. Predictive accuracy for disease‐free survival (DFS) and overall survival (OS) given by C‐index was equal and better for thickness (0.60 and 0.69) and tumor volume (0.61 and 0.69) as compared to T classification (0.59 and 0.64, respectively). For early‐stage T1 to T2 oral tongue cancer, thickness is a better predictor of nodal metastasis as compared to tumor volume and T classification.ConclusionConcordance between the tumor thickness and volume proves that tumor thickness can be taken as a surrogate and reliable predictor of outcomes instead of calculating the tumor volume.
Impact of school health management committees on health services delivery in Ghana: A national level assessment
Authors: Bowman Angela S. , Owusu Andrew , Trueblood Amber B. , Bosumtwi‐Sam Cynthia 
Published: May 2018

SummaryObjectivesTo examine the prevalence, determinants, and impact of local school health management committees on implementation of minimum‐recommended school health services delivery among basic and secondary schools in Ghana.MethodsNational level cross‐sectional data from the first‐ever assessment of Ghana Global‐School Health Policies and Practices Survey was utilized. Complex sample analyses were used to quantify school‐level implementation of recommended minimum package for health services delivery.ResultsOf 307 schools, 98% were basic and government run, and 33% offered at least half of the recommended health service delivery areas measured. Schools with a school health management committee (53%) were 4.8 (95% CI = 3.23–5.18) times as likely to offer at least 50% of the minimum health services package than schools that did not.ConclusionsThere is significant deficit concerning delivery of school health services in schools across Ghana. However, school health management committees positively impact implementation of health service delivery.Policy implicationsSchool health management committees provide a significant impact on delivery of school health services; thus, it is recommended that policy makers and programmers place greater emphasis on the value and need for these advisory boards in all Ghanaian schools.
Influence of climate on alpine stream chemistry and water sources
Authors: Foks Sydney S. , Stets Edward G. , Singha Kamini , Clow David W. 
Published: May 2018

AbstractThe resilience of alpine/subalpine watersheds may be viewed as the resistance of streamflow or stream chemistry to change under varying climatic conditions, which is governed by the relative size (volume) and transit time of surface and subsurface water sources. Here, we use end‐member mixing analysis in Andrews Creek, an alpine stream in Rocky Mountain National Park, Colorado, from water year 1994 to 2015, to explore how the partitioning of water sources and associated hydrologic resilience change in response to climate. Our results indicate that four water sources are significant contributors to Andrews Creek, including snow, rain, soil water, and talus groundwater. Seasonal patterns in source‐water contributions reflected the seasonal hydrologic cycle, which is driven by the accumulation and melting of seasonal snowpack. Flushing of soil water had a large effect on stream chemistry during spring snowmelt, despite making only a small contribution to streamflow volume. Snow had a large influence on stream chemistry as well, contributing large amounts of water with low concentrations of weathering products. Interannual patterns in end‐member contributions reflected responses to drought and wet periods. Moderate and significant correlations exist between annual end‐member contributions and regional‐scale climate indices (the Palmer Drought Severity Index, the Palmer Hydrologic Drought Index, and the Modified Palmer Drought Severity Index). From water year 1994 to 2015, the percent contribution from the talus‐groundwater end member to Andrews Creek increased an average of 0.5% per year (p < 0.0001), whereas the percent contributions from snow plus rain decreased by a similar amount (p = 0.001). Our results show how water and solute sources in alpine environments shift in response to climate variability and highlight the role of talus groundwater and soil water in providing hydrologic resilience to the system.
Numerical studies on the influences of the South‐to‐North Water Transfer Project on groundwater level changes in the Beijing Plain, China
Authors: Zhang Menglin , Hu Litang , Yao Lili , Yin Wenjie 
Published: May 2018

AbstractGroundwater is an important component of the water supply, and overexploitation has triggered many problems in the Beijing Plain. The South‐to‐North Water Transfer Project has been proposed as a promising solution to alleviate these problems. Evaluation of different scenarios of groundwater management after the implementation of the South‐to‐North Water Transfer Project is necessarily required. In this study, a numerical model of groundwater flow was established using FEFLOW software and was well calibrated by parameter optimization and groundwater withdrawal inversion in the Beijing Plain. Sixteen scenarios that considered groundwater exploitation, artificial recharge, and precipitation were designed to simulate the groundwater dynamics after 11 years of the project. The results showed that the groundwater level in the study area would recover to various degrees due to the reductions of groundwater withdrawal and the increments of infiltration; additionally, it was concluded that groundwater was significantly affected by precipitation. Generally, in the designed scenarios, the groundwater‐level increment in the upper streams of the model area was higher than that in the lower streams. The groundwater level would obviously increase from artificial recharge in the immediate and adjacent areas. In addition, modes of reducing exploitation had no significant influence on the change in groundwater level during the 11‐year study period. The developed model offers a reliable and effective way to improve groundwater management.
Prevalence and Risk of Vertebral Fractures in Primary Hyperparathyroidism: A Nested Case-Control Study
Authors: Ejlsmark-Svensson Henriette , Bislev Lise Sofie , Lajlev Siv , Harsløf Torben , Rolighed Lars , Sikjaer Tanja , Rejnmark Lars 
Published: May 2018

ABSTRACT

Prevalence of vertebral fractures (VFx) in primary hyperparathyroidism (PHPT) remains uncertain. We aimed to estimate the prevalence of VFx, investigate potential risk factors associated with VFx, and whether bone mineral density (BMD) differs between PHPT and osteoporotic patients with VFx. Through the Danish National Patient Register, we identified patients diagnosed with PHPT from 2005 to 2015. The diagnosis was verified by reviewing biochemical findings, and X-ray reports were reviewed by two investigators. Osteoporotic patients with VFx were identified from our outpatient clinic and matched on age and sex with PHPT patients with VFx. We identified 792 PHPT patients among whom spine X-ray was available from 588 patients. VFx were present in 122 (21%) patients and were equally frequent among sexes (77% females). Fractured patients were older (70 versus 63 years) and had lower heights (163 versus 166 cm) compared with nonfractured patients (p all &lt; 0.02). After stratification by age groups, the prevalence of VFx differed significantly between sexes (p &lt; 0.01). Ionized calcium and parathyroid hormone did not differ between groups. BMD at total hip and forearm were lower in fractured compared with nonfractured patients (p &lt; 0.03 for both) after adjusting for age, sex, and body mass index (BMI). Compared with osteoporotic patients with VFx (n = 108), BMD at the lumbar spine was higher in PHPT patients with VFx (n = 108) (p &lt; 0.01). This did not change by excluding patients with lumbar VFx (p &lt; 0.01). The severity of PHPT assessed by biochemistry does not seem to be associated with risk of VFx. Compared with osteoporosis, VFx seems to occur at a higher BMD in PHPT. © 2018 American Society for Bone and Mineral Research.
The chemokine fragment CXCL9(74–103) diminishes neutrophil recruitment and joint inflammation in antigen-induced arthritis
Authors: Boff Daiane , Crijns Helena , Janssens Rik , Vanheule Vincent , Menezes Gustavo B , Macari Soraia , Silva Tarcilia A , Amaral Flavio A , Proost Paul 
Published: May 2018

Abstract
This study investigates if treatment with a peptide corresponding to the 30 C-terminal amino acids of CXCL9, CXCL9(74–103), ameliorates joint inflammation in a murine model of antigen-induced arthritis (AIA). AIA was induced in male C57BL/6J mice. Intravenous injection of CXCL9(74–103), simultaneously performed with a tibiofemoral challenge with methylated BSA (mBSA) as antigen in mice immunized with mBSA, diminished the accumulation of leukocytes, in particular neutrophils, in the synovial cavity. The levels of the chemokines CXCL1, CXCL2, and CXCL6 and of the cytokine IL-6 were decreased in inflamed periarticular tissue of mice treated with the CXCL9-derived peptide compared to non-treated AIA mice. In addition, CXCL9(74–103) treatment substantially reduced joint and cartilage damage. CXCL9(74-103) competes with CXCL6 and CCL3 for binding to the glycosaminoglycans heparan sulfate and chondroitin sulfate in vitro. In vivo, CXCL9(74-103) quickly binds to blood vessels in joints as observed by confocal microscopy. Next, we evaluated if later treatment with CXCL9(74–103) had a beneficial impact on joint inflammation. CXCL9(74-103) injection 6 h after mBSA challenge still reduced neutrophil accumulation in the joint, although it did not reduce chemokine and IL-6 concentrations. However, a delay of treatment until 12 h after challenge had no effect on cell recruitment and chemokine and IL-6 levels. Taken together, we demonstrated that treatment with a peptide, which interferes with the interaction between chemokines and glycosaminoglycans, from the beginning of the disease controlled the massive accumulation of neutrophils in the joint of AIA mice, greatly impacting on joint inflammation and tissue damage.
Inhibition of chemokine-glycosaminoglycan interactions with the CXCL9-derived peptide CXCL9(74-103) reduces neutrophil influx and chemokine production in the joint of mice subjected to antigen-induced arthritis.
Patterns of growth in the presacral vertebral column of the leopard gecko (Eublepharis macularius)
Authors: Powell George Lawrence , Russell Anthony P. , Sutey Jennifer 
Published: May 2018

AbstractPostnatal growth patterns within the vertebral column may be informative about body proportions and regionalization. We measured femur length, lengths of all pre‐sacral vertebrae, and lengths of intervertebral spaces, from radiographs of a series of 21Eublepharis macularius, raised under standard conditions and covering most of the ontogenetic body size range. Vertebrae were grouped into cervical, sternal, and dorsal compartments, and lengths of adjacent pairs of vertebrae were summed before analysis. Femur length was included as an index of body size. Principal component analysis of the variance‐covariance matrix of these data was used to investigate scaling among them. PC1 explained 94.19% of total variance, interpreted as the variance due to body size. PC1 differed significantly from the hypothetical isometric vector, indicating overall allometry. The atlas and axis vertebrae displayed strong negative allometry; the remainder of the vertebral pairs exhibited weak negative allometry, isometry or positive allometry. PC1 explained a markedly smaller amount of variance for the vertebral pairs of the cervical compartment than for the remainder of the vertebral pairs, with the exception of the final pair. The relative standard deviations of the eigenvalues from the PCAs of the three vertebral compartments indicated that the vertebrae of the cervical compartment were less strongly integrated by scaling than were the sternal or dorsal vertebrae, which did not differ greatly between themselves in their strong integration, suggesting that the growth of the cervical vertebrae is constrained by the mechanical requirements of the head. Regionalization of the remainder of the vertebral column is less clearly defined but may be associated with wave form propagation incident upon locomotion, and by locomotory changes occasioned by tail autotomy and regeneration. Femur length exhibits negative allometry relative to individual vertebral pairs and to vertebral column length, suggesting a change in locomotor requirements over the ontogenetic size range.
Morphology of reproductive accessory glands in female Sepia pharaonis (Cephalopoda: Sepiidae) sheds light on egg encapsulation
Authors: Huang Jing‐Duan , Lee Shin‐Yu , Chiang Tzu‐Yin , Lu Chung‐Cheng , Lee Mong‐Fong 
Published: May 2018

AbstractThe pharaoh cuttlefish, Sepia pharaonis, is an important cephalopod fishery species in southeastern Asia, with understudied reproductive physiology. The present study aimed to investigate the cellular characteristics of epithelial cells found in the nidamental glands (NGs) and accessory NGs (ANGs), as well as the structural connections between these two glands in mature female S. pharaonis. A histological analysis revealed two types of epithelial cells in NGs: Alcian blue‐positive, PAS‐negative mucosubstance‐secreting cells and eosinophilic, PAS‐positive granule‐secreting cells. Using transmission electron microscopy, three types of epithelial cells were identified: cells with electron‐dense granules, cells with electron‐lucent granules, and cells with both cilia and microvilli in the apex. Mature ANGs contain an abundance of tubular units composed of epithelial cells resting on a thin layer of basal lamina. Innervated muscle cells are tightly adhered to the basal lamina. In addition, we observed epithelial canalization of ANG tubules penetrating through the connective tissue linking NGs and the walls of the tubules in ANGs, which allows the contents of the ANG tubules to be transported to the NGs. Our results suggest that ANGs participate in the encapsulation of the ova via the same pathway as NGs, which provides an important basis for future studies on the mechanism of protection provided by NGs and ANGs during embryonic development in S. pharaonis.