bluuebunny/crossref_metadata_2025_split huggingface dataset:
A study of reduced‐order 4DVAR with a finite element shallow water model
Authors: Altaf M. U. , Ambrozic M. , McCabe M. F. , Hoteit I. 
Published: August 2015

SummaryFour‐dimensional variational data assimilation (4DVAR) is frequently used to improve model forecasting skills. This method improves a model consistency with available data by minimizing a cost function measuring the model–data misfit with respect to some model inputs and parameters. Associated with this type of method, however, are difficulties related to the coding of the adjoint model, which is needed to compute the gradient of the 4DVAR cost function. Proper orthogonal decomposition (POD) is a model reduction method that can be used to approximate the gradient calculation in 4DVAR. In this work, two ways of using POD in 4DVAR are presented, namely model‐reduced 4DVAR and reduced adjoint 4DVAR (RA‐4DVAR). Both techniques employ POD to obtain a reduced‐order approximation of the forward linear tangent operator. The difference between the two methods lies in the treatment of the forward model. Model‐reduced 4DVAR performs minimization entirely in the POD‐reduced space, thereby achieving very low computational costs, but sacrificing accuracy of the end result. On the other hand, the RA‐4DVAR uses POD to approximate only the adjoint model. The main contribution of this study is a comparative performance analysis of these 4DVAR methodologies on a nonlinear finite element shallow water model. The sensitivity of the methods to perturbations in observations and the number of observation points is examined. The results from twin experiments suggest that the RA‐4DVAR method is easy to implement and computationally efficient and provides a robust approach for achieving reasonable results in the context of variational data assimilation. Copyright © 2015 John Wiley & Sons, Ltd.
Lower cognitive performance and white matter changes in testicular cancer survivors 10 years after chemotherapy
Authors: Stouten‐Kemperman Myrle M. , de Ruiter Michiel B. , Caan Matthan W.A. , Boogerd Willem , Kerst Martijn J. , Reneman Liesbeth , Schagen Sanne B. 
Published: August 2015

AbstractObjectiveChemotherapy (CT) is associated with adverse effects on cognition. Only few studies have investigated cognition in testicular cancer (TC) patients and studies on very late effects of CT on cognition are absent. Further, brain changes in relation to treatment have not been investigated in TC. The objective of the present study is to compare psychosocial functioning, cognitive performance and brain (micro)structure following surgery and CT for TC, against surgery (S)‐only.MethodsTwenty‐eight CT (43.1 ± 7.5 y) and 23 S‐only (48.2 ± 9.5y) TC survivors on average 14 yr post‐treatment were examined using questionnaires, neurocognitive tests, and 3T‐MRI [Diffusion Kurtosis Imaging (DKI), T1‐weighted and Fluid Attenuated Inversion Recovery]. A multivariate cognitive performance score (Mahalanobis distance) was calculated to indicate the grade of cognitive performance. Kurtosis parameters, gray matter, and white matter (WM) volume were calculated from MRI data.ResultsOverall, the CT group showed lower cognitive performance (5.35 ± 1.7) compared with the S‐only group (4.4 ± 0.9; P =0.03; d = 0.70). Further, TC patients reported more memory problems after CT. DKI revealed a significantly higher radial kurtosis after CT in several anterior and posterior brain areas (P < 0.05, corrected), but this was unrelated to cognitive performance.ConclusionsThis cross‐sectional study suggests that men receiving CT for TC are at risk for long‐term lower cognitive performance. Although CT affected WM microstructure, this was unrelated to cognitive performance. More extensive, preferably prospective studies are warranted to confirm these results and to provide more insight into the possible mechanisms behind the observed cognitive sequelae after treatment for TC. Hum Brain Mapp 36:4638–4647, 2015. © 2015 Wiley Periodicals, Inc.
The impact of caffeine on connexin expression in the embryonic chick cardiomyocyte micromass culture system
Authors: Ahir Bhavesh K. , Pratten Margaret K. 
Published: August 2015

AbstractCardiomyocytes are electrically coupled by gap junctions, defined as clusters of low‐resistance multisubunit transmembrane channels composed of connexins (Cxs). The expression of Cx40, Cx43 and Cx45, which are present in cardiomyocytes, is known to be developmentally regulated. This study investigates the premise that alterations in gap junction proteins are one of the mechanisms by which teratogens may act. Specifically, those molecules known to be teratogenic in humans could cause their effects via disruption of cell‐to‐cell communication pathways, resulting in an inability to co‐ordinate tissue development. Caffeine significantly inhibited contractile activity at concentrations above and including 1500 μm (P < 0.05), while not affecting cell viability and total protein, in the embryonic chick cardiomyocyte micromass culture system. The effects of caffeine on key cardiac gap junction protein (Cx40, Cx43 and Cx45) expression were analysed using immunocytochemistry and in‐cell Western blotting. The results indicated that caffeine altered the expression pattern of Cx40, Cx43 and Cx45 at non‐cytotoxic concentrations (≥2000 μm), i.e., at concentrations that did not affect total cell protein and cell viability. In addition the effects of caffeine on cardiomyocyte formation and function (contractile activity score) were correlated with modulation of Cxs (Cx40, Cx43 and Cx45) expression, at above and including 2000 μm caffeine concentrations (P < 0.05). These experiments provide evidence that embryonic chick cardiomyocyte micromass culture may be a useful in vitro method for mechanistic studies of perturbation of embryonic heart development. Copyright © 2015 John Wiley & Sons, Ltd.
Cortisol, HDL‐c, VLDL‐c, and APOE Polymorphisms as Laboratorial Parameters Associated to Cognitive Impairment No Dementia (CIND) and Dementia
Authors: Lara Vivian P. , Caramelli Paulo , Teixeira Antônio L. , Barbosa Maira T. , Carmona Karoline C. , Guimarães Henrique C. , Carvalho Maria G. , Fernandes Ana P. , Gomes Karina B. 
Published: August 2015

BackgroundPopulation aging is a global phenomenon whose main consequence is the increase of chronic degenerative diseases, including dementia. The aim of this case–control study was to evaluate the laboratorial parameters lipid profile, cortisol, and apolipoprotein E (APOE) gene genotype, comparing cognitively healthy controls and subjects with cognitive impairment no dementia (CIND) and dementia in a group of elderly people.MethodsThree hundred and nine individuals enrolled in the Pietà Study (Brazil) were divided into three groups: control (n = 158), CIND (n = 92), and dementia (n = 59). Participants were interviewed, went through examination, and had blood samples taken.ResultsAge and APOE showed significant differences among the groups, while sex and lipid profile did not. According to multivariate regression logistic analyses, higher cortisol levels, lower high‐density lipoprotein (HDL‐c) and very low‐density lipoprotein (VLDL‐c), presence of ε4 allele of APOE, and aging were associated with CIND and dementia.ConclusionThese laboratorial parameters are risk factors associated to CIND and dementia in the elderly people and should be investigated in order to develop strategies to prevent or delay the onset of dementia in the oldest‐old populations.
Fasting Lipoprotein Lipase Protein Levels Can Predict a Postmeal Increment of Triglyceride Levels in Fasting Normohypertriglyceridemic Subjects
Authors: Tsuzaki Kokoro , Kotani Kazuhiko , Yamada Kazunori , Sakane Naoki 
Published: August 2015

BackgroundAlthough a postprandial increment in triglyceride (TG) levels is considered to be a risk factor for atherogenesis, tests (e.g., fat load) to assess postprandial changes in TG levels cannot be easily applied to clinical practice. Therefore, fasting markers that predict postprandial TG states are needed to be developed. One current candidate is lipoprotein lipase (LPL) protein, a molecule that hydrides TGs. This study investigated whether fasting LPL levels could predict postprandial TG levels.MethodsA total of 17 subjects (11 men, 6 women, mean age 52 ± 11 years) with normotriglyceridemia during fasting underwent the meal test. Several fasting parameters, including LPL, were measured for the area under the curve of postprandial TGs (AUC‐TG).ResultsThe subjects’ mean fasting TG level was 1.30 mmol/l, and their mean LPL level was 41.6 ng/ml. The subjects’ TG levels increased after loading (they peaked after two postprandial hours). Stepwise multiple regression analysis demonstrated that fasting TG levels were a predictor of the AUC‐TG. In addition, fasting LPL mass levels were found to be a predictor of the AUC‐TG (β = 0.65, P < 0.01), and this relationship was independent of fasting TG levels.ConclusionFasting LPL levels may be useful to predict postprandial TG increment in this population.
Performance Evaluation of Three URiSCAN Devices for Routine Urinalysis
Authors: Ko Kiwoong , Kwon Min‐Jung , Ryu Seungho , Woo Hee‐Yeon , Park Hyosoon 
Published: August 2015

BackgroundThis study compares the diagnostic performance (in routine urinalysis) of three URiSCAN devices and three Roche analyzers to manual microscopy and quantitative assays.MethodsWe analyzed eight dipstick tests using three URiSCAN devices. The results were compared to those of the tests performed using three Roche analyzers. The results of leukocyte and erythrocyte screens were compared to those obtained using manual microscopy. Protein, glucose, pH, and specific gravity (SG) assays performed on the URiSCAN devices were compared with the results of corresponding quantitative assays.ResultsThe rates of agreement within one grade difference were found to be more than 94.3%. When compared with manual microscopy, the Optima provided better diagnostic performance for the detection of leukocytes compared with the Urisys 1100. Compared to the Urisys 2400, the Super plus provided better diagnostic performance with regard to both leukocytes and erythrocytes. There was good correlation between the three URiSCAN devices and each quantitative assay, except for SG detection.ConclusionThere were well correlated results between those of the three URiSCAN devices and those obtained using the corresponding Roche analyzers, quantitative assays, and manual microscopy. URiSCAN series devices are therefore suitable for routine urinalysis in clinical laboratories.
Botanical features for identification of Gymnosporia arenicola dried leaf
Authors: Da Silva Gustavo , Serrano Rita , Teixeira Gomes Elsa , Silva Olga 
Published: August 2015

AbstractGymnosporia arenicola Jordaan (Celastraceae) is a shrub or small tree, which naturally occurs in coastal sand dunes of Southern Mozambique and South Africa. Its dried leaf is often used in traditional medicine for the treatment of infectious and inflammatory diseases. Hereby, we present results of studies carried out according to the pharmacopoeia standards for the identification of herbal drugs, in the whole, fragmented, and powdered plant material. These results were complemented with scanning electron microscopy and histochemical techniques. The leaf microscopic analysis revealed a typical dorsiventral mesophyll with a corresponding spongy parenchyma–palisade parenchyma ratio of 0.60, anomocytic and paracytic stomata, papillate cells with a diameter of 4.00 ± 0.40 µm, multicellular uniseriate nonglandular trichomes with a length of 27.00 ± 4.10 µm and cristalliferous idioblasts containing calcium oxalate cluster crystals with a diameter of 23.04 ± 5.84 µm. The present findings demonstrate that the G. arenicola leaf has both nonglandular trichomes and hypoderm, features not previously described in the corresponding botanical section (Gymnosporia sect. Buxifoliae Jordaan). The establishment of these new botanical markers for the identification of G. arenicola leaf is essential for quality, safety and efficacy reasons. Microsc. Res. Tech. 78:1001–1009, 2015. © 2015 Wiley Periodicals, Inc.
Internal Partitions of Regular Graphs
Authors: Ban Amir , Linial Nati 
Published: August 2015

AbstractAn internal partition of an n‐vertex graph is a partition of V such that every vertex has at least as many neighbors in its own part as in the other part. It has been conjectured that every d‐regular graph with vertices has an internal partition. Here we prove this for . The case is of particular interest and leads to interesting new open problems on cubic graphs. We also provide new lower bounds on and find new families of graphs with no internal partitions. Weighted versions of these problems are considered as well.
Evaluation of apparent diffusion coefficient and MR volumetry as independent associative factors for extra‐prostatic extension (EPE) in prostatic carcinoma
Authors: Lim Christopher , Flood Trevor A. , Hakim Shaheed W. , Shabana Wael M. , Quon Jeffrey S. , El‐Khodary Mohamed , Thornhill Rebecca E. , El Hallani Soufiane , Schieda Nicola 
Published: August 2015

BackgroundTo assess mean apparent diffusion coefficient (ADC) and MR‐derived tumor volume (Vt) as associative factors for extra‐prostatic extension (EPE) in prostate cancer (PCa).MethodsWith institutional review board approval, 73 consecutive patients diagnosed with PCa at trans‐rectal ultrasound biopsy underwent preoperative multi‐parametric (T2W+DWI+DCE) 3 Tesla MRI before radical prostatectomy between 2012 and 2014; 52% (38/73) patients had EPE. Clinical parameters including: age, prostate serum antigen (PSA), digital rectal examination (DRE) and percentage positive cores (PPC) were recorded. Two blinded radiologists subjectively evaluated for EPE using PI‐RADS with T2W‐MRI. A third blinded radiologist recorded: mean ADC (mm2/s) of tumor and tumor volume on ADC and T2W (derived from planar volumetry). VtMAX (the largest volume on ADC or T2W) was documented. Multivariate and receiver operator characteristic analyses were performed.ResultsThere were no significant differences in age, DRE, or Gleason score between groups (P = 0.52, 0.06, 0.61, 0.36). PSA approached significance being higher with EPE (12.9 ± 12.6 versus 8.2 ± 7.4; P = 0.06). PPC was higher with EPE (60.9 ± 21.9% versus 38.3 ± 21.6%; P < 0.01) with an area under the curve (AUC) of 0.78 and sensitivity/specificity = 75.7/75% when PPC ≥ 45%. AUC for T2W‐MRI was 0.46–0.51 with sensitivity/specificity = 40.0–42.9/48.6–57.1% (R1, R2). Inter‐observer agreement was fair, k = 0.39. There was no difference in mean ADC between groups (0.89 ± 0.25 versus 0.88 ± 0.19 [EPE] mm2/s), P = 0.70. T2W‐Vt, ADC‐Vt, and VtMAX were larger with EPE (5.1 ± 7.4, 5.8 ± 6.5, 6.3 ± 7.4 cm3 versus 1.6 ± 1.8, 1.8 ± 1.3, 2.1 ± 1.8), P < 0.01. VtMAX AUC was 0.77 with sensitivity/specificity = 78.4/73.5% when VtMAX ≥ 2.1 cm3 which outperformed all other parameters (P > 0.05) except PPC (P = 0.6) for the diagnosis EPE.ConclusionMR volumetry and percentage of positive core biopsies are associated with EPE; whereas, in this study, other clinical and MR parameters including mean ADC and subjective T2W‐MR analysis were not useful for assessment of EPE. J. MAGN. RESON. IMAGING 2016;43:726–736.
Pacific Ocean SST and Z500 climate variability and western U.S. seasonal streamflow
Authors: Sagarika Soumya , Kalra Ajay , Ahmad Sajjad 
Published: August 2015

ABSTRACTThe current study focuses on evaluating the relationship between the Pacific Ocean climate variability and western US streamflow for six hydrologic regions of the western United States, as defined by United States Geological Survey: Rio Grande, Upper Colorado, Lower Colorado, Great Basin, Pacific Northwest, and California. The singular‐valued decomposition (SVD) technique was applied on data for 50 years (1960–2010) of sea‐surface temperatures (SST), geopotential height index of 500 mbar (Z500), and 90 unimpaired western US streamflows; the results established a spatio‐temporal association for each major hydrologic region in the western United States with Pacific Oceanic variability. An approach using a 3‐ to 9‐month lead time was utilized, i.e. the previous year's July to August SST/Z500, the previous year's October to December SST/Z500 to predict streamflow for current year spring–summer (April to September), spring (April to June), and summer (July to September) seasons. Significant regions in the Pacific were identified that influence hydrology of the western United States. The traditional El Niño/Southern Oscillation (ENSO) and Pacific Decadal Oscillation regions were identified along with regions over eastern Russia, Canadian British Columbia, and the ‘Hondo’ region along the east coast of Japan. Z500 showed pronounced association with 3‐month lead time streamflow, whereas SST had better association with 6‐month lead time streamflow. The SVD results showed improvement in correlation values of smaller spatial regions over larger regions, and a lagged response of adjacent hydrologic regions to the same physical indicators. The results obtained in this study could be helpful in improving the current forecasting models for water management.
A population‐based assessment of melanoma: Does treatment in a regional cancer center make a difference?
Authors: Rivard Justin , Kostaras Xanthoula , Shea‐Budgell Melissa , Chin‐Lenn Laura , Quan May Lynn , McKinnon J. Gregory 
Published: August 2015

BackgroundRegionalization of care to specialized centers has improved outcomes for several cancer types. We sought to determine if treatment in a regional cancer center (RCC) impacts guideline adherence and outcomes for patients with melanoma.MethodsIn Alberta, Canada, 561 patients with stage I–IIIC primary melanoma were diagnosed between January 2009 and December 2010. The electronic health record was used to capture demographic and pathologic data. Provincial guidelines for sentinel lymph node biopsy (SLNB) and wide local excision (WLE) are based on recommendations of several pre‐existing guidelines including the National Comprehensive Cancer Network.Results148 of 561 patients were identified as having been treated at a RCC. Median follow‐up was 45 months. Patients treated at the RCC presented with higher stage melanomas. The RCC was more likely to follow guideline recommendations for performing SLNB (81.3% vs. 55.4%, P < 0.0001) but not for the extent of WLE (76.6% vs. 84.1%, P = 0.054). Overall survival was impacted by tumor thickness (HR 1.14, P < 0.0001), ulceration (HR 5.58, P < 0.0001), and mitoses (HR 0.59, P = 0.05).ConclusionsThe RCC more closely followed guidelines for SLNB but not for WLE. Despite patients treated at the RCC presenting with a more advanced stage, overall survival and disease‐free survival appear to not be affected by treatment center. J. Surg. Oncol. 2015 111:173–178. © 2015 Wiley Periodicals, Inc.
Surgery of gastric cancer and esophageal cancer: Does age matter?
Authors: Nienhueser Henrik , Kunzmann Romy , Sisic Leila , Blank Susanne , Strowitzk Moritz J. , Bruckner Thomas , Jäger Dirk , Weichert Wilko , Ulrich Alexis , Büchler Markus W. , Ott Katja , Schmidt Thomas 
Published: August 2015

IntroductionIn the past, elderly patients with upper GI cancers were excluded from surgery or multimodal treatment only due to their advanced age. In an aging society this way of patient selection seems to be questionable. The aim of this retrospective exploratory study was to investigate how patients with upper GI cancer over the age of 70 years differ from younger patients in the postoperative course and which parameters influence overall survival in older patient populations.Patients and MethodsFrom 2002 to 2012 1,005 patients underwent resection of esophageal or gastric cancer at the University of Heidelberg. 272 patients were older than 70 years and analyzed in subgroups (70–74 years: n = 146; 75–79 years: n = 82; 80 years or older: n = 44). Patients older than 70 years were compared to patients under 70 years (n = 733) with focus on differences in patients characteristics and outcome. Statistical analyses were made retrospectively on a prospective database.ResultsFewer older patients were treated neoadjuvantly (< 70 years: 41.5%; > 70 years: 24.7%, P < 0.001) and extended resection (abdominothoracic approach) was applied less frequently compared to patients under 70 years (< 70 years: 38.9%; > 70 years: 19.9%, P < 0.001). The pNM‐category (HR 1.41/2.56) and R‐status (HR 1.78) remain the most important predictive factor for survival (all < 0.001). Female patients had a longer survival than men over the age of 70 (84.9 vs. 23.5 months, P < 0.01). Patients over 80 years had a significant shortened overall survival (> 80 years: 16.7 vs. < 70 years: 37.4 months) compared to the other subgroups (P < 0.001) and a significant increased in‐hospital mortality (> 80 years: 20.5% vs. < 70 years: 6.0%, P = 0.002).ConclusionsAn exclusion from surgical therapy due to advanced age in general seems not to be justified. However, the decision for a surgical resection in patients over 80 years should be made with caution. pNM‐categories and R0‐resection remain the most important predictive factors for overall survival in all subgroups. No survival benefit for neoadjuvant treatment in patients over 70 years was found, while women survived longer than men. However, the decision concerning a (radio) chemotherapy should be made individually in each patient. J. Surg. Oncol. 2015; 112:387–395. © 2015 Wiley Periodicals, Inc.
Insights Gained by Modeling the Kinetics of Archetypal Hydrogen Atom Transfer Reactions: NH3 + ·H ⇆ H2N· + H2 and CH4 + ·H ⇆ H3C· + H2
Authors: Zavitsas Andreas A. 
Published: August 2015

ABSTRACTExperimental measurements of the kinetics of the title reactions extend to temperature ranges of 1360 K for the ammonia‐hydrogen reaction and of 1602 K for the methane‐hydrogen reaction. Curved plots of ln(k) versus 1/T are obtained. Many theoretical calculations modeling these reactions routinely use tunneling corrections to match experiment. The steepness and curvatures of the plots are modeled successfully in this work and are shown to be caused solely by changes in the bond dissociation energies of the bonds involved in the reactions without invoking tunneling or any other adjustable parameters. The conclusion that tunneling does not contribute significantly to the rates in the temperature range of the measurements is in stark contrast with those theoretical calculations invoking large tunneling factors in the experimental temperature range. Support for the conclusion is provided by theoretical calculations of harmonic quantum transition state theory implementing instanton theory. There is direct experimental evidence that significant tunneling occurs in some H atom transfers, as with isotopomers of H2 + ·H and other H transfers at very low temperatures. However, there is no direct experimental evidence of significant tunneling contributions to the rates of the title reactions in the temperature range of the measurements. Insights are gained into what specific forces must be overcome by the enthalpy of activation for reaction to occur.
Multiscale Control of Hierarchical Structure in Crystalline Block Copolymer Nanoparticles Using Microfluidics
Authors: Bains Aman , Cao Yimeng , Moffitt Matthew G. 
Published: August 2015

Hierarchical semicrystalline block copolymer nanoparticles are produced in a segmented gas‐liquid microfluidic reactor with top‐down control of multiscale structural features, including nanoparticle morphologies, sizes, and internal crystallinities. Control of multiscale structure on disparate length scales by a single control variable (flow rate) enables tailoring of drug delivery nanoparticle function including release rates.
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