bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of bedrock permeability on stream base flow mean transit time scaling relationships: 2. Process study of storage and release
Authors: Hale V. Cody , McDonnell Jeffrey J. , Stewart Michael K. , Solomon D. Kip , Doolitte Jim , Ice George G. , Pack Robert T. 
Published: February 2016

AbstractIn Part 1 of this two‐part series, Hale and McDonnell (2016) showed that bedrock permeability controlled base flow mean transit times (MTTs) and MTT scaling relations across two different catchment geologies in western Oregon. This paper presents a process‐based investigation of storage and release in the more permeable catchments to explain the longer MTTs and (catchment) area‐dependent scaling. Our field‐based study includes hydrometric, MTT, and groundwater dating to better understand the role of subsurface catchment storage in setting base flow MTTs. We show that base flow MTTs were controlled by a mixture of water from discrete storage zones: (1) soil, (2) shallow hillslope bedrock, (3) deep hillslope bedrock, (4) surficial alluvial plain, and (5) suballuvial bedrock. We hypothesize that the relative contributions from each component change with catchment area. Our results indicate that the positive MTT‐area scaling relationship observed in Part 1 is a result of older, longer flow path water from the suballuvial zone becoming a larger proportion of streamflow in a downstream direction (i.e., with increasing catchment area). Our work suggests that the subsurface permeability structure represents the most basic control on how subsurface water is stored and therefore is perhaps the best direct predictor of base flow MTT (i.e., better than previously derived morphometric‐based predictors). Our discrete storage zone concept is a process explanation for the observed scaling behavior of Hale and McDonnell (2016), thereby linking patterns and processes at scales from 0.1 to 100 km2.
Evaporation tagging and atmospheric water budget analysis with WRF: A regional precipitation recycling study for West Africa
Authors: Arnault Joel , Knoche Richard , Wei Jianhui , Kunstmann Harald 
Published: February 2016

ABSTRACTRegional precipitation recycling is the measure of the contribution of local evaporation E to local precipitation. This study provides a set of two methods developed in the Weather Research and Forecasting WRF model system for investigating regional precipitation recycling mechanisms: (1) tracking of tagged atmospheric water species originating from evaporation in a source region, ie E‐tagging, and (2) three‐dimensional budgets of total and tagged atmospheric water species. These methods are used to quantify the effect of return flow and nonwell vertical mixing neglected in the computation of the bulk precipitation recycling ratio. The developed algorithms are applied to a WRF simulation of the West African Monsoon 2003. The simulated region is characterized by vertical wind shear condition, i.e., southwesterlies in the low levels and easterlies in the mid‐levels, which favors return flow and nonwell vertical mixing. Regional precipitation recycling is investigated in 100 × 100 and 1000 × 1000 km2 areas. A prerequisite condition for evaporated water to contribute to the precipitation process in both areas is that it is lifted to the mid‐levels where hydrometeors are produced. In the 100 × 100 (1000 × 1000) km2 area the bulk precipitation recycling ratio is 0.9 (7.3) %. Our budget analysis reveals that return flow and nonwell vertically mixed outflow increase this value by about +0.2 (2.9) and +0.2 (1.6) %, respectively, thus strengthening the well‐known scale‐dependency of regional precipitation recycling.
An evolving view of transition zone and midmantle viscosity
Authors: King Scott D. 
Published: February 2016

AbstractIn a new study, Liu and Zhong (this issue) investigate the impact of thermochemical anomalies in the lower mantle on the viscosity structure inferred from the geoid, finding that both thermochemical and thermal only mantle models can be reconciled with the geoid with nearly the same viscosity structure. They also find a preference for radial viscosity models where the lowest viscosity layer occurs in the transition zone as opposed to the upper mantle. While their weak transition zone viscosity model is not unprecedented, it differs from the most widely used viscosity models, which assume the smallest viscosity occurs in the upper mantle. Liu and Zhong's investigation does not support the midmantle viscosity increase recently suggested by Rudolph et al. [2015] who use a nearly identical methodology but different tomographic model.
Impact of Cenosphere on the Erosion Wear Response of Woven Hybrid Jute–Glass Epoxy Composites
Authors: Dalbehera Soma , Acharya S. K. 
Published: February 2016

ABSTRACTIn the present case, the solid particle erosion characteristics of the cenosphere‐filled glass–jute (GJJG) hybrid epoxy composites have been studied experimentally. Jute with (45°−45°) and glass with (0−90°) fabric orientation have been used to fabricate the composites. Different doses of cenosphere particles (5, 10, 15, and 20 wt%) were also added to the matrix material. A steady‐state erosion rate of these composites has been studied with various impingement angles (30°, 45°, 60°, and 90°) with different impact velocities (48, 70, and 82 m/s). The results indicate that 20 wt% filled cenosphere particles to (GJJG) hybrid epoxy composite exhibit better wear resistance. The maximum erosion at 45° and 60° impingement angles also indicates the semiductile behavior of the composite. The morphologies of the worn surfaces were analyzed using a scanning electron microscope, and it was revealed that inclusion of higher weight percentage of cenosphere particles restricted the impact velocity to erode the surface. The increase in erosion resistance of the developed composites is the outcome of this result.
Synthesis of Functionalized 2‐Trifluoromethylquinolines and their Heteroaromatic Analogues
Authors: Khutoryanskiy Viktor V. , Biitseva Angelina V. , Mykhailiuk Pavel K. 
Published: February 2016

AbstractElectron‐rich anilines and amino heterocycles were converted in one step into N‐protected functionalized aminoethyl 2‐trifluoromethylquinolines and their heteroaromatic analogues. The N‐carbamate protecting group can be easily cleaved under acidic conditions to give the corresponding amines.
Combination of lignin polyol–tannin adhesives and polyethylenimine for the preparation of green water‐resistant adhesives
Authors: Faris Abbas Hasan , Rahim Afidah Abdul , Ibrahim Mohamad Nasir Mohamad , Alkurdi Adel Mustafa , Shah Irfan 
Published: February 2016

ABSTRACTIn this study, a green adhesive from renewable lignin and tannin was developed with polyethylenimine (PEI) with a method to improve the water resistance of the lignin/tannin adhesive. Lignin polyols were prepared through the liquefaction of oil‐palm empty fruit bunches. The characteristics of the adhesive samples were compared with those of a commercial phenol–formaldehyde resin. Three plywood specimens bonded with the new adhesive showed a very high tensile strength (63.04 MPa) and were very water resistant. The effect of the solid content of the adhesives on the tensile strength and gel time and various weight ratios of PEI on the tensile strength and water resistance of the plywood specimens were evaluated. Thermal stability tests revealed that the lignin polyol–tannin/PEI adhesives had a high heat resistance (360 °C). © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43437.
Dual‐Functional Nanographene Oxide as Cancer‐Targeted Drug‐Delivery System to Selectively Induce Cancer‐Cell Apoptosis
Authors: Zhou Binwei , Huang Yanyu , Yang Fang , Zheng Wenjie , Chen Tianfeng 
Published: February 2016

AbstractConstruction of bioresponsive drug‐delivery nanosystems could enhance the anticancer efficacy of anticancer agents and reduce their toxic side effects. Herein, by using transferrin (Tf) as a surface decorator, we constructed a cancer‐targeted nanographene oxide (NGO) nanosystem for use in drug delivery. This nanosystem (Tf‐NGO@HPIP) drastically enhanced the cellular uptake, retention, and anticancer efficacy of loaded drugs but showed much lower toxicity to normal cells. The nanosystem was internalized through receptor‐mediated endocytosis and triggered pH‐dependent drug release in acidic environments and in the presence of cellular enzymes. Moreover, Tf‐NGO@HPIP effectively induced cancer‐cell apoptosis through activation of superoxide‐mediated p53 and MAPK pathways along with inactivation of ERK and AKT. Taken together, this study demonstrates a good strategy for the construction of bioresponsive NGO drug‐delivery nanosystems and their use as efficient anticancer drug carriers.
Randomized clinical trial comparing long-term quality of life for Billroth IversusRoux-en-Y reconstruction after distal gastrectomy for gastric cancer
Authors: Nakamura M , Nakamori M , Ojima T , Iwahashi M , Horiuchi T , Kobayashi Y , Yamade N , Shimada K , Oka M , Yamaue H 
Published: February 2016

AbstractBackgroundPatients' quality of life (QoL) deteriorates remarkably after gastrectomy. Billroth I reconstruction following distal gastrectomy has the physiological advantage of allowing food to pass through the duodenum. It was hypothesized that Billroth I reconstruction would be superior to Roux-en-Y reconstruction in terms of long-term QoL after distal gastrectomy. This study compared two reconstructions in a multicentre prospective randomized clinical trial to identify the optimal reconstruction procedure.MethodsBetween January 2009 and September 2010, patients who underwent gastrectomy for gastric cancer were randomized during surgery to Billroth I or Roux-en-Y reconstruction. The primary endpoint was assessment of QoL using the Functional Assessment of Cancer Therapy – Gastric (FACT-Ga) questionnaire 36 months after surgery.ResultsA total of 122 patients were enrolled in the study, 60 to Billroth I and 62 to Roux-en-Y reconstruction. There were no differences between the two groups in terms of postoperative complications or mortality, and no significant differences in FACT-Ga total score (P = 0·496). Symptom scales such as epigastric fullness (heaviness), diarrhoea and fatigue were significantly better in the Billroth I group at 36 months after gastrectomy (heaviness, P = 0·040; diarrhoea, P = 0·046; fatigue, P = 0·029). The rate of weight loss in the third year was lower for patients in the Billroth I group (P = 0·046).ConclusionThe choice of anastomotic reconstruction after distal gastrectomy resulted in no difference in long-term QoL in patients with gastric cancer. Registration number: NCT01065688 (http://www.clinicaltrials.gov).
Characterization of in vitro metabolites of irisflorentin by rat liver microsomes using high‐performance liquid chromatography coupled with tandem mass spectrometry
Authors: Jia Yan‐Wei , Zeng Zhong‐Qiu , Shi Hai‐Li , Liang Jian , Liu Yi‐Ming , Tang Ya‐Xiong , Liao Xun 
Published: February 2016

AbstractBelamcanda chinensis has been extensively used as antibechic, expectorant and anti‐inflammatory agent in traditional medicine. Irisflorentin is one of the major active ingredients. However, little is known about the metabolism of irisflorentin so far. In this work, rat liver microsomes (RLMs) were used to investigate the metabolism of this compound for the first time. Seven metabolites were detected. Five of them were identified as 6,7‐dihydroxy‐5,3′,4′,5′‐tetramethoxy isoflavone (M1), irigenin (M2), 5,7,4′‐trihydroxy‐6,3′,5′‐trimethoxy isoflavone (M3), 6,7,4′‐trihydroxy‐5,3′,5′‐trimethoxy isoflavone (M4) and 6,7,5′‐trihydroxy‐5,3′,4′‐trimethoxy isoflavone (M5) by means of NMR and/or HPLC‐ESI‐MS. The structures of M6 and M7 were not elucidated because they produced no MS signals. The predominant metabolite M1 was noted to be a new compound. Interestingly, it was found to possess anticancer activity much higher than the parent compound. The enzymatic kinetic parameters of M1 revealed a sigmoidal profile, with Vmax = 12.02 μm/mg protein/min, Km = 37.24 μm, CLint = 0.32 μL/mg protein/min and h = 1.48, indicating the positive cooperation. For the first time in this work, a new metabolite of irisflorentin was found to demonstrate a much higher biological activity than its parent compound, suggesting a new avenue for the development of drugs from B. chinensis, which was also applicable for other herbal plants. Copyright © 2016 John Wiley & Sons, Ltd.
Fine‐Tuning Covalent Inhibition of Bacterial Quorum Sensing
Authors: Amara Neri , Gregor Rachel , Rayo Josep , Dandela Rambabu , Daniel Erik , Liubin Nina , Willems H. Marjo E. , Ben‐Zvi Anat , Krom Bastiaan P. , Meijler Michael M. 
Published: February 2016

AbstractEmerging antibiotic resistance among human pathogens has galvanized efforts to find alternative routes to combat bacterial virulence. One new approach entails interfering with the ability of bacteria to coordinate population‐wide gene expression, or quorum sensing (QS), thus inhibiting the production of virulence factors and biofilm formation. We have recently developed such a strategy by targeting LasR, the master regulator of QS in the opportunistic human pathogen Pseudomonas aeruginosa, through the rational design of covalent inhibitors closely based on the core structure of the native ligand. We now report several groups of new inhibitors, one of which, fluoro‐substituted ITC‐12, displayed complete covalent modification of LasR, as well as effective QS inhibition in vitro and promising in vivo results. In addition to their potential clinical relevance, this series of synthetic QS modulators can be used as a tool to further unravel the complicated QS regulation in P. aeruginosa.
A Structure‐Guided Switch in the Regioselectivity of a Tryptophan Halogenase
Authors: Shepherd Sarah A. , Menon Binuraj R. K. , Fisk Heidi , Struck Anna‐Winona , Levy Colin , Leys David , Micklefield Jason 
Published: February 2016

AbstractFlavin‐dependent halogenases are potentially useful biocatalysts for the regioselective halogenation of aromatic compounds. Haloaromatic compounds can be utilised in the synthesis and biosynthesis of pharmaceuticals and other valuable products. Here we report the first X‐ray crystal structure of a tryptophan 6‐halogenase (SttH), which enabled key residues that contribute to the regioselectivity in tryptophan halogenases to be identified. Structure‐guided mutagenesis resulted in a triple mutant (L460F/P461E/P462T) that exhibited a complete switch in regioselectivity; with the substrate 3‐indolepropionate 75 % 5‐chlorination was observed with the mutant in comparison to 90 % 6‐chlorination for the wild‐type SttH. This is the first clear example of how regiocomplementary halogenases can be created from a single parent enzyme. The biocatalytic repertoire of SttH was also expanded to include a range of indolic and non‐indolic substrates.
A Comparative Study of Fuzzy Techniques to Handle Uncertainty: An Industrial Grinding Process
Authors: Virivinti Nagajyothi , Mitra Kishalay 
Published: February 2016

AbstractThe deterministic optimization models for chemical processes assume perfect information, i.e., the system parameters involved in the models should have fixed values. However, the knowledge about these parameters is often either not easy to obtain or, if available, subjected to uncertainty involved in determining them (e.g. experiments, regression etc.). The optimization results obtained using these deterministic models are, therefore, not robust to uncertainties in the parameters of the system. In this work, fuzzy based approaches, e.g. fuzzy chance constrained programming (FCCP) and fuzzy expected value model (FEVM), have been applied to a multi‐objective optimization problem of the industrial grinding process to carry out the uncertainty analysis and the results are compared with respect to the power of risk averseness adopted in the approaches used. These methods assume the uncertain parameters as fuzzy numbers and membership function is used to represent the degree of uncertainty in them. The extent of constraint satisfaction due to the presence of uncertain parameters can be accommodated assuming credibility of constraint satisfaction under FCCP framework whereas the robust set of parameters in the FEVM approach is determined by considering the expectation terms for objectives and constraints. Moreover, the issue of nonlinear relation of uncertain parameters has been handled by adopting simulation based approaches while computing the credibility. The results obtained by FCCP technique show how the presence of uncertainty leads to an operating zone of varied risk appetite of a decision maker by using different uncertain measures such as credibility, possibility and necessity. These approaches are very generic and can be adopted for the study of parametric sensitivity for any process model in a novel manner.
Adsorption of Nickel Ions on Oxygen‐Functionalized Carbons
Authors: Kern Andreas M. , Zierath Bodo , Fey Tobias , Etzold Bastian J. M. 
Published: February 2016

AbstractThe adsorption of nickel(II) ions on pristine and wet‐chemically oxidized microporous carbons is studied. The nature and acidity of the resulting oxygen functional groups are characterized by temperature‐programmed desorption and point of zero charge measurements. The maximal nickel ion adsorption capacity of the resulting high‐affinity Langmuir‐type adsorption equilibrium is strongly influenced by the oxidative pretreatment. At maximum, loadings of 7.5 wt % could be obtained for carbons showing oxygen content of 12.5 mmol g−1. A linear correlation of the ion uptake with the surface oxygen content could be deduced. In a kinetic study, it could be proved that the uptake of nickel at room temperature is a slow process and that the time for adsorption is independent of oxygen content, carbon type, and nickel loading.
Lanthanide‐Doped Nanoparticles with Near‐Infrared‐to‐Near‐Infrared Luminescence for Bioimaging
Authors: Wei Yurong , Yang Xiangdong , Ma Yurou , Wang Shengfu , Yuan Quan 
Published: February 2016

AbstractLanthanide (Ln, or rare‐earth) doped nanoparticles are well‐known for their prominent optical properties and have been widely used for biological applications, especially in biological assays and medical imaging. Recently, the extensive attention of near infrared (NIR) wavelength range has dramatically increased for its fast feedback, high spatial resolution and deep tissue penetration. Tissues have minimal absorbance in this region. While a lot of excellent reviews cover various aspects of biomedical imaging based on lanthanide doped nanoparticles, there has not been a review that systematically summarizes NIR‐to‐NIR imaging with lanthanide doped nanoparticles. In this review, we focus on the recent development of NIR‐to‐NIR imaging based on lanthanide doped nanoparticles, and discuss challenges and opportunities in it.
Folic Acid Functionalized PFBT Fluorescent Polymer Dots for Tumor Imaging
Authors: Cao Fengwen , Xiong Liqin 
Published: February 2016

AbstractFolic acid functionalized PFBT‐COOH and PFBT‐NH2 polymer dots were prepared using a nano precipitation method, and their applications for tumor imaging in vitro and in vivo were demonstrated for the first time. The synthesized FA‐PFBT‐COOH polymer dots were 50–60 nm in diameter with a zeta potential of greater than −30 mV in water, while the synthesized FA‐PFBT‐NH2 polymer dots were 90–105 nm in diameter with a zeta potential of greater than −20 mV in water. Furthermore, the FA‐PFBT‐COOH polymer dots produced stronger fluorescence intensity in water solution as well as in the cells than the FA‐PFBT‐NH2 polymer dots, and were able to image H1299 tumors in living mice after intravenous injection. This study showed the great potentials of FA‐PFBT‐COOH polymer dots as fluorescent nanoprobes for biomedical imaging.
Design and Fabrication of Plasmonic Nanostructures with DNA for Surface‐Enhanced Raman Spectroscopy Applications
Authors: Leng Chunbo , Wang Cheng , Xiu Huixin , Qu Xiangmeng , Chen Lizhen , Tang Qian , Li Li 
Published: February 2016

AbstractPlasmonic nanostructures display unique and strongly enhanced optical properties, therefore hold great promise for a wide range of spectroscopic applications, particularly surface‐enhanced Raman spectroscopy (SERS). It is well acknowledged that the major contributions to SERS arise from molecules positioned in nanojunctions where the optical field is intensively concentrated due to localized surface plasmon excitations. One of the key challenges in SERS therefore lies in the design and fabrication of plasmonic nanostructures with controllable nanojunctions. In recent years, by exploiting the unparalleled base‐pairing self‐recognition properties, DNA‐mediated assembly has emerged as a powerful and programmable tool for the accurate construction of complex and hierarchical plasmonic nanostructures with well‐defined geometry and topology. In this review, we will summarize recent advances on design and fabrication of a rich variety of plasmonic nanostructures by virtue of DNA nanotechnology, and discuss their optical properties as well as applications in SERS.
Self‐Assembled DNA Nanostructures for Drug Delivery
Authors: Jia Ruokun , Wang Ting , Jiang Qiao , Wang Zhengang , Song Chen , Ding Baoquan 
Published: February 2016

AbstractDue to the uniform nanoscale sizes, well‐defined shapes, precise spatial addressability and prominent biocompatibility, self‐assembled DNA nanostructures have been intensively studied for their biomedical applications. This review summarizes the recent development of DNA nanotechnology in cancer therapy, and discusses the challenges and potential strategies to advance the methodologies of cancer treatments.
DNA Directed Self‐Assembly of Fluorescent Colloidal Semiconductor Quantum Dots and Plasmonic Metal Nanoparticles Heterogeneous Nanomaterials
Authors: Guo Yan , Hu Yue , Deng Zhengtao 
Published: February 2016

AbstractThe exciton‐plasmon interaction between fluorescent colloidal semiconductor quantum dots and plasmonic metal nanoparticles may lead to emission quenching or enhancement of quantum dots, which have potential applications in renewable energy, nanophotonics, and biosensing. Semiconductor quantum dots and metal nanoparticles hybrids with controlled geometry, distance, and stoichiometry are crucial for the potential applications. While DNA nanotechnology, based on Watson‐Crick base‐pairing interactions between two single‐stranded DNAs, has provided unique opportunities to generate fully programmable, functional metal nanoparticles and semiconductor quantum dots hybrid nanomaterials, and offers precisely control over the spacing, orientation, and chirality of the components. This review provides the highlights of the recent progresses in DNA directed self‐assembly of colloidal semiconductor quantum dots and metallic nanoparticles heterogeneous nanomaterials. We also discuss the challenges and the trends in DNA directed self‐assembly of semiconductor quantum dots and metallic nanoparticles hybrid nanomaterials.