bluuebunny/crossref_metadata_2025_split huggingface dataset:
Application of polynomial chaos theory as an accurate and computationally efficient proxy model for heterogeneous steam‐assisted gravity drainage reservoirs
Authors: Jain Tarang , Patel Rajan G. , Trivedi Japan 
Published: November 2017

AbstractReservoir modeling and simulation have become important elements of reservoir management. However, high computational cost associated with the use of numerical simulators make them cumbersome, especially with large‐scale simulation models and complex oil recovery processes like steam‐assisted gravity drainage (SAGD). A data‐driven proxy model can be an alternative to predict SAGD recovery performance in real heterogeneous reservoirs, however, computationally efficient proxy model which can handle large number of input variables while providing accurate results requires further attention. In this work, a proxy model based on polynomial chaos expansion (PCE) is developed to predict the production parameters of SAGD reservoir. Karhunen–Loeve (KL) expansion is used to parameterize input variables in terms of random variables using which PCE further calculates production data for the given reservoir. To calculate coefficients of PCE, probabilistic collocation method is used. To demonstrate the functionality of the proposed approach, case study of a SAGD reservoir located in northern Alberta, Canada is shown in this paper. Various production parameters predicted from the PCE proxy model are compared with the actual simulation results and other proxy models based on radial basis functions (RBF) and artificial neural networks (ANN). From the results, it can be said that PCE proxy model demonstrates good agreement with full‐physics simulation results and outperforms other proxy methods in terms of training data required and accuracy of predictions. In addition, since proposed PCE proxy model greatly reduces the computing cost, it potentially paves the way for expedited and frequent execution of uncertainty quantification, assisted history matching, and optimization workflows, resulting into efficient reservoir management and significant monetary benefits.
An Investigation of PEFC Sub‐Zero Startup: Influence of Initial Conditions and Residual Water
Authors: Stahl P. , Biesdorf J. , Boillat P. , Friedrich K. A. 
Published: November 2017

AbstractIsothermal cold starts of polymer electrolyte fuel cells were performed at sub‐zero temperatures and analyzed by means of neutron radiography in order to unravel the relation between the preconditioning of the cell and the cold start capability. It was found out that the initial humidification state of the membrane (determined by its resistance) has a clear correlation with the duration of the initial phase of the cold start, but not with the total duration of startup until cell failure. In the experimental setup the impact of realistic and commercial sealing solutions was taken into account by adding an edge channel. The impact of water accumulations in this region on the cold start capability was assessed. Liquid water located in the outer perimeter of a cell could be directly verified to freeze during cell cool down by a novel dual spectrum neutron radiography method. The amount of water accumulated in the outer cell perimeter showed some correlation with the total duration of the cold start. It was found out that residual water located in the edge channel can initiate freezing of a substantial part of the active area nearby.
Tau PET imaging predicts cognition in atypical variants of Alzheimer's disease
Authors: Phillips Jeffrey S. , Das Sandhitsu R. , McMillan Corey T. , Irwin David J. , Roll Emily E. , Da Re Fulvio , Nasrallah Ilya M. , Wolk David A. , Grossman Murray 
Published: November 2017

AbstractAccumulation of paired helical filament tau contributes to neurodegeneration in Alzheimer's disease (AD). 18F‐flortaucipir is a positron emission tomography (PET) radioligand sensitive to tau in AD, but its clinical utility will depend in part on its ability to predict cognitive symptoms in diverse dementia phenotypes associated with selective, regional uptake. We examined associations between 18F‐flortaucipir and cognition in 14 mildly‐impaired patients (12 with cerebrospinal fluid analytes consistent with AD pathology) who had amnestic (n = 5) and non‐amnestic AD syndromes, including posterior cortical atrophy (PCA, n = 5) and logopenic‐variant primary progressive aphasia (lvPPA, n = 4). Amnestic AD patients had deficits in memory; lvPPA in language; and both amnestic AD and PCA patients in visuospatial function. Associations with cognition were tested using sparse regression and compared to associations in anatomical regions‐of‐interest (ROIs). 18F‐flortaucipir uptake was expected to show regionally‐specific correlations with each domain. In multivariate analyses, uptake was elevated in neocortical areas specifically associated with amnestic and non‐amnestic syndromes. Uptake in left anterior superior temporal gyrus accounted for 67% of the variance in language performance. Uptake in right lingual gyrus predicted 85% of the variance in visuospatial performance. Memory was predicted by uptake in right fusiform gyrus and cuneus as well as a cluster comprising right anterior hippocampus and amygdala; this eigenvector explained 57% of the variance in patients' scores. These results provide converging evidence for associations between 18F‐flortaucipir uptake, tau pathology, and patients' cognitive symptoms.
Estimating the opportunity costs of bed‐days
Authors: Sandmann Frank G. , Robotham Julie V. , Deeny Sarah R. , Edmunds W. John , Jit Mark 
Published: November 2017

AbstractOpportunity costs of bed‐days are fundamental to understanding the value of healthcare systems. They greatly influence burden of disease estimations and economic evaluations involving stays in healthcare facilities. However, different estimation techniques employ assumptions that differ crucially in whether to consider the value of the second‐best alternative use forgone, of any available alternative use, or the value of the actually chosen alternative. Informed by economic theory, this paper provides a taxonomic framework of methodologies for estimating the opportunity costs of resources. This taxonomy is then applied to bed‐days by classifying existing approaches accordingly. We highlight differences in valuation between approaches and the perspective adopted, and we use our framework to appraise the assumptions and biases underlying the standard approaches that have been widely adopted mostly unquestioned in the past, such as the conventional use of reference costs and administrative accounting data. Drawing on these findings, we present a novel approach for estimating the opportunity costs of bed‐days in terms of health forgone for the second‐best patient, but expressed monetarily. This alternative approach effectively re‐connects to the concept of choice and explicitly considers net benefits. It is broadly applicable across settings and for other resources besides bed‐days.
The effect of temporal manipulation of transforming growth factor beta 3 and fibroblast growth factor 2 on the derivation of proliferative chondrocytes from mensenchymal stem cells—A study monitored by quantitative reverse transcription polymerase chain reaction and molecular beacon based nanosensors
Authors: Tay Li Min , Wiraja Christian , Wu Yingnan , Yang Zheng , Lee Eng Hin , Xu Chenjie 
Published: November 2017

AbstractProliferative chondrocytes are critical to realize regeneration of damaged epiphyseal growth plate. However, acquiring autologous replacement cells involves highly invasive procedures and often results in limited cell quantity. Mesenchymal stem cells (MSCs) are a potential source of chondrogenic cells for the treatment of cartilage disorders and injuries. The temporal effect of transforming growth factor beta 3 (TGFβ3) and fibroblast growth factor 2 (FGF2) on the derivation of proliferative chondrocytes from MSCs in three‐dimensional agarose was investigated by manipulating the duration of TGFβ3 and FGF2 treatment. The differentiation process was monitored by quantitative reverse transcription polymerase chain reaction (qRT‐PCR) as well as nanosensors containing two molecular beacons that target critical biomarkers for proliferative chondrocytes (i.e., collagen type‐II messenger ribonucleic acid [mRNA] and Ki67 mRNA). The molecular beacon‐based nanosensors were found to be comparable to qRT‐PCR in measuring mRNA expression and thus providing a noninvasive mean to screen and monitor culture samples. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 895–904, 2018.
Characterization of printed PLA scaffolds for bone tissue engineering
Authors: Grémare Agathe , Guduric Vera , Bareille Reine , Heroguez Valérie , Latour Simon , L'heureux Nicolas , Fricain Jean‐Christophe , Catros Sylvain , Le Nihouannen Damien 
Published: November 2017

AbstractAutografts remain the gold standard for orthopedic transplantations. However, to overcome its limitations, bone tissue engineering proposes new strategies. This includes the development of new biomaterials such as synthetic polymers, to serve as scaffold for tissue production. The objective of this present study was to produce poly(lactic) acid (PLA) scaffolds of different pore size using fused deposition modeling (FDM) technique and to evaluate their physicochemical and biological properties. Structural, chemical, mechanical, and biological characterizations were performed. We successfully fabricated scaffolds of three different pore sizes. However, the pore dimensions were slightly smaller than expected. We found that the 3D printing process induced decreases in both, PLA molecular weight and degradation temperatures, but did not change the semicrystalline structure of the polymer. We did not observe any effect of pore size on the mechanical properties of produced scaffolds. After the sterilization by γ irradiation, scaffolds did not exhibit any cytotoxicity towards human bone marrow stromal cells (HBMSC). Finally, after three and seven days of culture, HBMSC showed high viability and homogenous distribution irrespective of pore size. Thus, these results suggest that FDM technology is a fast and reproducible technique that can be used to fabricate tridimensional custom‐made scaffolds for tissue engineering. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 887–894, 2018.
Evaluation of central venous catheters coated with a noble metal alloy—A randomized clinical pilot study of coating durability, performance and tolerability
Authors: Björling Gunilla , Johansson Dorota , Bergström Linda , Strekalovsky Anton , Sanchez Javier , Frostell Claes , Kalman Sigridur 
Published: November 2017

AbstractThe use of Central Venous Catheters (CVCs) commonly results in complications. Coatings with silver or metal alloys can reduce the risk associated with the use of CVC. We have evaluated the durability of a noble metal coated CVC (the Bactiguard Infectious Protection, BIP CVC) and compared with an uncoated CVC for clinical tolerability (Adverse Events, AEs) and performance, in order to create a baseline for a large future study. Patients undergoing major surgery, randomised at a 2:1 ratio to BIP CVC (n = 22) or standard CVC (n = 12), were catheterized 9 ‐ 12 days, respectively. Adverse events, microbial colonization and metal release were measured.Findings: There were no AEs in the BIP CVC‐group, but 5 AEs occurred in 4 patients (1 patient had 2 AEs) in the standard CVC‐group, p = 0.011 (whereof 3 were catheter related). The BIP CVC showed an initial release of coating metals in blood (gold, silver and palladium), which rapidly decreased and were far below Permitted Paily Exposure (PDE) for chronical use. The levels of silver concentration were far below those needed to develop microbial resistance. The performance was equal, and there was no difference concerning microbial colonization, for the two CVCs.Conclusion: In this pilot study the BIP CVC had significantly lower AEs and showed a comparable performance to the standard CVC. The coating was durable throughout the study length (up to 16 days) and toxicological evaluation showed good safety margins. Larger studies are needed. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 2337–2344, 2018.
Hyaluronic acid in the tail and limb of amphibians and lizards recreates permissive embryonic conditions for regeneration due to its hygroscopic and immunosuppressive properties
Authors: Alibardi Lorenzo 
Published: November 2017

AbstractThe present review focuses on the role of hyaluronate (hyaluronic acid; HA) during limb and tail regeneration in amphibians and lizards mainly in relation to cells of the immune system. This non‐sulfated glycosaminoglycan (GAG) increases in early stages of wound healing and blastema formation, like during limb or tail embryogenesis, when the immune system is still immature. The formation of a regenerating blastema occurs by the accumulation of mesenchymal cells displaying embryonic‐like antigens and HA. This GAG adsorbs large amount of water and generates a soft tissue over 80% hydrated where mesenchymal and epithelial cells can move and interact, an obligatory passage for organ regeneration. GAGs and HA in particular rise to a high amount and coat plasma membranes of blastema cells forming a shield that likely impedes to the circulating immune cells to elicit an immune reaction against the embryonic‐like antigens present on blastema cells. The evolution of limb–tail regeneration in amphibians dates back to the Devonian‐Carboniferous, while tail regeneration in lizards is a more recent evolution process, possibly occurred since the Jurassic, which is unique among amniotes. Both processes are associated with the reactivation of proliferating embryonic programs that involve the upregulation of genes for Wnt, non‐coding RNAs, and HA synthesis in an immune‐suppress organ, the regenerative blastema. Failure of maintaining a lasting HA synthesis for the formation of a highly hydrated blastema leads to scarring, the common healing process of amniotes equipped with an efficient immune system. The study of amphibian and lizard regeneration indicates that attempts to stimulate organ regeneration in other vertebrates require the induction of a highly hydrated and immune‐depressed, HA‐rich environment, similar to the extracellular environment present during development.
Co‐delivery of hypoxia inducible factor‐1α small interfering RNA and 5‐fluorouracil to overcome drug resistance in gastric cancer SGC‐7901 cells
Authors: Chen Yunna , Sun Li , Guo Dongdong , Wu Ziteng , Chen Weidong 
Published: November 2017

AbstractBackgroundDrug resistance cancer cells have become a major problem in chemotherapy. To solve this problem, the co‐delivery of small interefering RNA (siRNA) and 5‐fluorouracil chitosan nanoparticles was employed, aiming to reverse the multidrug resistance of gastric cancer SGC‐7901 cells in vitro.MethodsChitosan nanoparticles were prepared using an ionic gel method. siRNA nanoparticles were characterized by gel retardation assays. Particle size and zeta potential were measured to confirm nanoparticle formation. The transfection efficiency of siRNA was determined by flow cytometry and high‐content screening. Western blotting and a quantitative real‐time‐polymerase chain reaction were used to assess the silencing efficiency of siRNA. Accumulation and efflux experiments for rhodamine‐123, cell migration experiments, cell sensitivity analyses and cell apoptosis assays were used to determine whether siRNA could reverse multidrug resistance. A systemic toxicity assay was used to evaluate the safety of nanoparticles.ResultsCompared to naked siRNA, the co‐delivery system demonstrated a higher transfection efficiency and gene silencing efficiency by inhibiting the efflux of P‐glycoprotein and cell migration. Moreover, the combination treatment with siRNA and 5‐fluorouracil co‐delivered by chitosan nanoparticles can increase the sensitivity of drug resistance cells and cell apoptosis. Finally, the safety of nanoparticles was evaluated in vivo and the results obtained suggested that nanoparticles did not have any obvious toxicity.ConclusionsCo‐delivery of siRNA and 5‐fluorouracil chitosan nanoparticles is an attractive strategy for overcoming multidrug resistance.
Preharvest treatments with salicylates enhance nutrient and antioxidant compounds in plum at harvest and after storage
Authors: Martínez‐Esplá Alejandra , Zapata Pedro J , Valero Daniel , Martínez‐Romero Domingo , Díaz‐Mula Huertas M , Serrano María 
Published: November 2017

AbstractBACKGROUNDPrevious reports have addressed the effectiveness of salicylic acid (SA), acetylsalicylic acid (ASA) and methylsalicylate (MeSA) postharvest treatments on maintaining quality properties during storage in several commodities. However, there is no literature regarding the effect of preharvest treatments with salicylates on plum quality attributes (at harvest or after long‐term cold storage), which was evaluated in this research.RESULTSAt harvest, weight, firmness, individual organic acids, sugars, phenolics, anthocyanins and total carotenoids were found at higher levels in plums from SA‐, ASA‐ and MeSA‐treated trees than in those from controls. During storage, softening, colour changes and acidity losses were delayed in treated fruits as compared to controls. In addition, organic acids and antioxidant compounds were still found at higher levels in treated than in control plums after 40 days of storage. Results show a delay in the postharvest ripening process due to salicylate treatments, which could be attributed to their effect in delaying and decreasing ethylene production.CONCLUSIONPreharvest treatment with salicylates could be a safety, eco‐friendly and new tool to improve (at harvest) and maintain (during storage) plum quality and especially its content of bioactive compounds with antioxidant properties, increasing the health effects of plum consumption. © 2017 Society of Chemical Industry
Recovery and stability over time of phenolic fractions by an industrial filtration system of olive mill wastewaters: a three‐year study
Authors: Bellumori Maria , Cecchi Lorenzo , Romani Annalisa , Mulinacci Nadia , Innocenti Marzia 
Published: November 2017

AbstractBACKGROUNDThe recovery of phenolic compounds from olive milling is recognized as strategic for producers. The aim of this work was to evaluate the quality and stability of retentates obtained from olive mill wastewaters treated with a membrane filtration system constituted by a micro‐, ultra‐ and nanofiltration, followed by a final reverse osmosis, over three crop seasons. Efficiency was evaluated in terms of phenolic amount in the retentates and of organic load in the final discarded waters. Phenolic compounds were quantified using tyrosol as external standard.RESULTSOur study highlighted a reproducibility of the process over years and a low organic load in permeates from reverse osmosis. Hydroxytyrosol was very stable in the liquid products at 18–28 °C over 24 months of storage. The retentates from reverse osmosis showed the highest phenolic content (78.6 mg g−1 dry matter in 2015), associated with a potassium content of 22 g kg−1.CONCLUSIONSThe liquid concentrated retentates showed an unexpected stability over time of their bioactive phenolic compounds, particularly of hydroxytyrosol. These samples recovered from olive mill wastewaters can be good sources of natural antioxidants and potassium to guarantee the correct intake and to formulate new food ingredients or food products. © 2017 Society of Chemical Industry
Identification of Salvia species using high‐performance liquid chromatography combined with chemical pattern recognition analysis
Authors: Wang Yang , Jiang Kun , Wang Lijun , Han Dongqi , Yin Guo , Wang Jue , Qin Bin , Li Shaoping , Wang Tiejie 
Published: November 2017

AbstractSalvia miltiorrhiza, also known as Danshen, is a widely used traditional Chinese medicine for the treatment of cardiovascular diseases and hematological abnormalities. The root and rhizome of Salvia przewalskii and Salvia yunnanensis have been found as substitutes for Salvia miltiorrhiza in the market. In this study, the chemical information of 14 major compounds in Salvia miltiorrhiza and its substitutes were determined using a high‐performance liquid chromatography method. Stepwise discriminant analysis was adopted to select the characteristic variables. Partial least squares discriminant and hierarchical cluster analysis were performed to classify Salvia miltiorrhiza and its substitutes. The results showed that all of the samples were correctly classified both in partial least squares discriminant analysis and hierarchical cluster analysis based on the four compounds (caffeic acid, rosmarinic acid, salvianolic acid B, and salvianolic acid A). This method can not only distinguish Salvia miltiorrhiza and its substitutes, but also classify Salvia przewalskii and Salvia yunnanensis. The method can be applied for the quality assessment of Salvia miltiorrhiza and identification of unknown samples.
Pediatric tinnitus: A clinical perspective
Authors: Chan Kenny H. , Jensen Emily L. , Gao Dexiang 
Published: November 2017

Objectives/HypothesisTo define the clinical features and natural history of pediatric tinnitus from a practicing otolaryngologist's perspective and formulate hypotheses therein.Study DesignRetrospective chart review.MethodsA retrospective chart review of the electronic medical record was undertaken. Only relevant records with a prior otolaryngology clinic visit and audiologic testing were included. Patients seen during the last 2 years of the study period were contacted and completed a questionnaire to assess change in tinnitus and quantify potential alterations in quality of life, associated symptoms, and natural history.ResultsOne hundred eighty subjects with mean/median age of 11.5/11.5 years were identified. Hearing loss was identified in 40 subjects (22.2%). Etiology of tinnitus was identified in 95 subjects (52.8 %). Tinnitus‐specific and/or nonspecific therapies were given to 80 subjects (44.4%). Of the 54 available subjects, 28 (51.9%) participated in the telephone questionnaire. Tinnitus complaints shifted favorably to the improvement or resolution categories (P = .001) between the initial clinic visit and the telephone interview. Shorter duration of tinnitus was associated with a higher probability of having improved tinnitus (P = .046).ConclusionsThis study distinguishes pediatric tinnitus from adult tinnitus in terms of lower association with underlying hearing loss, lower likelihood of reported anxiety, and higher likelihood of improvement and resolution. There are opportunities for tinnitus prevention in the areas of reducing head injury and noise‐induced hearing loss.Level of Evidence4. Laryngoscope, 128:727–731, 2018
In Silico Studies of Mammalian δ‐ALAD Interactions with Selenides and Selenoxides
Authors: Andrei Nogara Pablo , Batista Teixeira Rocha João 
Published: November 2017

AbstractPrevious studies have shown that the mammalian δ‐aminolevulinic acid dehydratase (δ‐ALAD) is inhibited by selenides and selenoxides, which can involve thiol oxidation. However, the precise molecular interaction of selenides and selenoxides with the active center of the enzyme is unknown. Here, we try to explain the interaction of selenides and the respective selenoxides with human δ‐ALAD by in silico molecular docking. The in silico data indicated that Se atoms of selenoxides have higher electrophilic character than their respective selenides. Further, the presence of oxygen increased the interaction of selenoxides with the δ‐ALAD active site by O…Zn coordination. The interaction of S atom from Cys124 with the Se atom indicated the importance of the nucleophilic attack of the enzyme thiolate to the organoselenium molecules. These observations help us to understand the interaction of target proteins with organoselenium compounds.