bluuebunny/crossref_metadata_2025 huggingface dataset:
Modeling nitrogen loading in a small watershed in Southwest China using a DNDC model with hydrological enhancements
Authors: Deng J. , Zhou Z. , Zhu B. , Zheng X. , Li C. , Wang X. , Jian Z.
Published: July 2011

Abstract. The degradation of water quality has been observed worldwide, and inputs of nitrogen (N), along with other nutrients, play a key role in the process of contamination. The quantification of N loading from non-point sources at a watershed scale has long been a challenge. Process-based models have been developed to address this problem. Because N loading from non-point sources result from interactions between biogeochemical and hydrological processes, a model framework must include both types of processes if it is to be useful. This paper reports the results of a study in which we integrated two fundamental hydrologic features, the SCS (Soil Conservation Service) curve function and the MUSLE (Modified Universal Soil Loss), into a biogeochemical model, the DNDC. The SCS curve equation and the MUSLE are widely used in hydrological models for calculating surface runoff and soil erosion. Equipped with the new added hydrologic features, DNDC was substantially enhanced with the new capacity of simulating both vertical and horizontal movements of water and N at a watershed scale. A long-term experimental watershed in Southwest China was selected to test the new version of the DNDC. The target watershed's 35.1 ha of territory encompass 19.3 ha of croplands, 11.0 ha of forest lands, 1.1 ha of grassplots, and 3.7 ha of residential areas. An input database containing topographic data, meteorological conditions, soil properties, vegetation information, and management applications was established and linked to the enhanced DNDC. Driven by the input database, the DNDC simulated the surface runoff flow, the subsurface leaching flow, the soil erosion, and the N loadings from the target watershed. The modeled water flow, sediment yield, and N loading from the entire watershed were compared with observations from the watershed and yielded encouraging results. The sources of N loading were identified by using the results of the model. In 2008, the modeled runoff-induced loss of total N from the watershed was 904 kg N yr−1, of which approximately 67 % came from the croplands. The enhanced DNDC model also estimated the watershed-scale N losses (1391 kg N yr−1) from the emissions of the N-containing gases (ammonia, nitrous oxide, nitric oxide, and dinitrogen). Ammonia volatilization (1299 kg N yr−1) dominated the gaseous N losses. The study indicated that process-based biogeochemical models such as the DNDC could contribute more effectively to watershed N loading studies if the hydrological components of the models were appropriately enhanced.
Boron isotope fractionation during brucite deposition from artificial seawater
Authors: Xiao J. , Xiao Y. K. , Liu C. Q. , Jin Z. D.
Published: July 2011

Abstract. Experiments involving boron incorporation into brucite (Mg(OH)2) from magnesium-free artificial seawater with pH values ranging from 9.5 to 13.0 were carried out to better understand the incorporation behavior of boron into brucite and the influence of it on Mg/Ca-SST proxy and δ11B-pH proxy. The results show that both the concentration of boron in deposited brucite ([B]d) and its boron partition coefficient (Kd) between deposited brucite and final seawater are controlled by the pH of the solution. The incorporation capacity of boron into brucite is almost the same as that into corals, but much stronger than that into oxides and clay minerals. The isotopic compositions of boron in deposited brucite (δ11Bd) are higher than those in the associated artificial seawater (δ11Bisw) with fractionation factors ranging between 1.0177 and 1.0569, resulting from the preferential incorporation of B(OH)3 into brucite. Both boron adsorptions onto brucite and the precipitation reaction of H3BO3 with brucite exist during deposition of brucite from artificial seawater. The simultaneous occurrence of both processes determines the boron concentration and isotopic fractionation of brucite. The isotopic fractionation behaviors and mechanisms of boron incorporated into brucite are different from those into corals. The existence of brucite in corals can affect the δ11B and Mg/Ca in corals and influences the Mg/Ca-SST proxy and δ11B-pH proxy negatively. The relationship between δ11B and Mg/Ca in corals can be used to judge the existence of brucite in corals, which should provide a reliable method for better use of δ11B and Mg/Ca in corals to reconstruct paleo-marine environment.
Modelling the seasonal variability of the Antarctic Slope Current
Authors: Mathiot P. , Goosse H. , Fichefet T. , Barnier B. , Gallée H.
Published: July 2011

Abstract. One of the main features of the oceanic circulation along Antarctica is the Antarctic Slope Current (ASC). This circumpolar current flows westwards and contributes to communication between the three major oceanic basins around Antarctica. The ASC is not very well known due to remote location and the presence of sea ice during several months, allowing in situ studies only during summertime. Moreover, only few modelling studies of this current have been carried out. Here, we investigate the sensitivity of this simulated current to four different resolutions in a coupled ocean-sea ice model and to two different atmospheric forcing sets. Two series of simulations are conducted. For the first series, global model configurations are run at coarse (2°) to eddy-permitting (0.25°) resolutions with the same atmospheric forcing. For the second series, simulations with two different atmospheric forcings are performed using a regional circumpolar configuration (south of 30° S) at 0.5° resolution. The first atmospheric forcing is based on a global atmospheric reanalysis and satellite data, while the second is based on a downscaling of the global atmospheric reanalysis by a regional atmospheric model calibrated to Antarctic meteorological conditions. Sensitivity experiments to resolution indicate that a minimum model resolution of 0.5° is needed to capture the dynamics of the ASC in terms of water mass transport and recirculation. Sensitivity experiments to atmospheric forcing fields shows that the wind speed along the Antarctic coast strongly controls the water mass transport and the seasonal cycle of the ASC. An increase in annual mean of easterlies by about 30 % leads to an increase in the mean ASC transport by about 40 %. Similar effects are obtained on the seasonal cycle: using a wind forcing field with a larger seasonal cycle (+30 %) increases by more than 30 % the amplitude of the seasonal cycle of the ASC. To confirm the importance of wind seasonal cycle, a simulation without wind speed seasonal cycle is carried out. This simulation shows a decrease by more than 50 % of the amplitude of the ASC transport seasonal cycle without changing the mean value of ASC transport.
Cytoplasmic Staining of TTF-1 Antibody in the Diagnosis of Hepatocellular Carcinoma: Study on 299 Cases Using Tissue Microarray
Authors: Cao Qinghua , Liu Fang , Xiao Ping , Wang Min , Lin Yuan , Ye Ziyin , Che Lihong , Xue Ling
Published: July 2011

The diagnosis of hepatocellular carcinoma (HCC) remains obscure in some complicated cases. Thyroid transcription factor-1 (TTF-1) was presumed to be helpful in the diagnosis of HCC. This paper aims to study the utility of TTF-1 in the diagnosis and differential diagnosis of HCC and to assign clinicopathological correlations. Immunohistochemical detection of TTF-1 is performed with tissue microarray which contains a total of 781 cases including 299 hepatocellular carcinomas (HCCs), 31 intrahepaticcholangiocarcinomas (ICCs), 86 metastatic adenocarcinomas (MACs), 5 metastatic hepatocellular carcinomas (mHCCs), 9 hepatoblastomas (HBs), 40 renal clear cell carcinomas (RCCs), 215 adjacent nonneoplastic hepatic tissue, and 96 normal hepatic tissue. The result shows that TTF-1 is positive in 55.2% (165/299) HCCs, 6.4% (2/31) ICCs, 3.5% (3/86) MACs, 60% (3/5) mHCCs, 33.3% (3/9) HBs, 0% (0/40) RCCs, 99.0% (213/215) adjacent nonneoplastic hepatic tissue, and 95.8% (93/96) normal hepatic tissue. Expression of TTF-1 is correlated with differentiation of HCC, but not with patients' age, gender, serum AFP, tumor size, number of tumor nodules, and tumor thrombus in vein or bile duct. These data suggest that TTF-1 antibody is sensitive and specific in HCC and might serve as a candidate for the diagnosis and differential diagnosis of HCC.
Development of Topical Niosomal Gel of Benzoyl Peroxide
Authors: Vyas Jigar , Vyas Puja , Raval Dhaval , Paghdar Paresh
Published: July 2011

Benzoyl peroxide is macrolide antibiotic used commonly for the treatment of acne either alone or in combination. But it suffers from side effects like skin redness, irritation, itching, and edema. Niosomes, a nonionic surfactant vesicular formulation, have been explored extensively for topical application to enhance skin penetration as well as to improve skin retention of drugs. In the present study, Benzoyl peroxide was entrapped into niosomes by thin film hydration technique, and various process parameters were optimized by partial factorial design. The optimized niosomal formulation was incorporated into HPMC K15 gel and extensively characterized for percentage drug entrapment (PDE) and in vitro release performance. The stability of above formulation was studied at different temperatures. The present study demonstrated prolongation of drug release, increased drug retention into skin, and improved permeation across the skin after encapsulation of benzoyl peroxide into niosomal topical gel.
MRI-Based Identification of an Appropriate Point of Needle Insertion for Patients with Idiopathic Carpal Tunnel Syndrome to Avoid Median Nerve Injury
Authors: Uchiyama Shigeharu , Itsubo Toshiro , Nakamura Koichi , Murakami Hironori , Momose Toshimitsu , Kato Hiroyuki
Published: July 2011

To identify a safe entry point for needle insertion in patients with idiopathic carpal tunnel syndrome (CTS), cross-sectional images of the wrist MRI of 45 normal volunteers and 180 consecutive patients with idiopathic CTS were reviewed. Insertion of the needle from the five different entry points into the carpal tunnel was simulated by drawing a 1-pixel line, and the incidence of contact with the median nerve was compared. In the CTS patients, the lowest incidence was 3% when inserted at one-third of the length between the FCR and FCU tendons on the ulnar side at the level of the distal part of the distal radioulnar joint and 4% at the mid point between the palmaris longus tendona and the flexor carpi ulnaris tendon. It was greater in the advanced stage of CTS than the less severe CTS. We recommend those two entry points.
Fixed Point for Partial Metric Spaces
Authors: Mohsenalhosseini S. A. M. , Mazaheri H. , Dehghan M. A. , Zareh A.
Published: July 2011

We consider the partial metric on a set X, define ϵ-fixed point for maps, and obtain some sufficient and necessary conditions on that, also
we obtain some sufficient and necessary theorems on ϵ-fixed point.
Fixed Points and Existence Theorems of Maximal Elements with Applications in FC-Spaces
Authors: He Rong-Hua
Published: July 2011

We present some fixed point theorems and existence theorems of maximal elements in FC-space from which we derive several coincidence theorems. Applications of these results to generalized equilibrium problems and minimax theory will be given. Our results improve and generalize some recent results.
Process for Producing Nano-Alpha-Alumina Powder
Authors: Mirjalili Fatemeh , Abdullah Luqman Chuah , Mohamad Hasmaliza , Fakhru'l-Razi A. , Dayang Radiah A. B. , Aghababazadeh R.
Published: July 2011

This paper is trying to explore the effect of stirring time on the synthesis of nano-α-Alumina particles. In this study, alumina nanoparticles were synthesized through alkoxide route using sol-gel method, where aqueous solutions of aluminum isopropoxide and 0.5 M aluminum nitrate nanohydrate were used for preparing alumina sol. Sodium dodecylbenzen sulfonate (SDBS) was used as the surfactant stabilizing agent. The prepared solution was stirred at different times (24, 36, 48, and 60 hours) at 60°C. The Samples were, then, characterized by X-ray diffraction, thermogravimetry analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and Transmission Electron Microscopy(TEM) . The introduction of different stirring times affected the particle size and shape and the degree of aggregation. By increasing the stirring time, (starting from 24 to 48 hours) the particle size decreased, but agglomeration became hard for 60 hours of stirring time. The finest particle size (20–30 nm) was obtained at 48-hour stirring time.
A Medium Viscous Acrylic Cement Enhances Uniformity of Cement Filling and Reduces Leakage in Cancellous Bone Augmentation
Authors: Boger Andreas , Wheeler Kurtis
Published: July 2011

Vertebroplasty is an efficient procedure to treat osteoporotic vertebral fractures. Cement leakage is considered to be the most severe complication during vertebroplasty. At high cement viscosities, the risk of leakage is reduced. However, injection forces are highly increased, requiring the use of high force injection systems with the lack in tactile force feedback. Therefore, an acrylic cement was developed showing medium initial viscosity and which still allows to be manually applied using syringes. An established model favoring leakage was used to observe the filling pattern and leaked cement mass. The method used included the simulation of body temperature, and all materials submitted are approved medical products. When applied just after preparation, the medium viscous cement resulted in good cement filling and less cement leakage than low viscosity cement. The added clinical value of the new cement is that the waiting time for the physician will be shortened to zero minutes without compromising the safety for the procedure.
The U-Shaped Curve in the Low Countries: A Replication Study
Authors: Haanstra Folkert , Damen Marie-Louise , van Hoorn Marjo
Published: July 2011

The U-curve model of graphic development posits a decline in aesthetic production in middle childhood. This model has been criticized as reflecting a preference for the modernist style in Western art, and a number of studies have tried to confirm or disprove its assumptions. This study is a partial replication of previous research in this field. To this end, artists, art educators, adult nonartists, and children judged drawings by children and adults from five different age groups: 5-, 8-, 11-, and 14-year-old and adult nonartists and artists. Subjects were asked to draw a self-portrait and to make a "sad" drawing. Outcomes show that, in contrast to adult nonartists and children, many art trained judges still hold a modernist view.
Analysis of Gene‐Gene Interactions
Authors: Gilbert‐Diamond Diane , Moore Jason H.
Published: July 2011

The goal of this unit is to introduce gene‐gene interactions (epistasis) as a significant complicating factor in the search for disease susceptibility genes. This unit begins with an overview of gene‐gene interactions and why they are likely to be common. Then, it reviews several statistical and computational methods for detecting and characterizing genes with effects that are dependent on other genes. The focus of this unit is genetic association studies of discrete and quantitative traits because most of the methods for detecting gene‐gene interactions have been developed specifically for these study designs. Curr. Protoc. Hum. Genet. 70:1.14.1‐1.14.12 © 2011 by John Wiley & Sons, Inc.
Reporting of Diagnostic Cytogenetic Results
Authors: Ligon Azra H. , Morton Cynthia C. , Bieber Frederick R. , Fletcher Jonathan A. , Giersch Anne B.S. , Kantarci Sibel , Leach Natalia , Lee Charles , Sandstrom Mary , Weremowicz Stanislawa , Xiao Sheng , Cin Paola Dal
Published: July 2011

This appendix, developed by the staff at the Clinical Cytogenetics Laboratory at the Brigham and Women's Hospital, includes a comprehensive list of current “macros” or standardized statements used to facilitate reporting of cytogenetic results. These are provided as a reference for other laboratories. The statements are organized under the general categories of constitutional or acquired abnormalities and subdivided into analysis type (GTG‐banding or FISH). Multi‐specimen usage macros are included that can be applied to two or more specimen types. Curr. Protoc. Hum. Genet. 70:A.1D.1‐A.1D.25 © 2011 by John Wiley & Sons, Inc.
Integrating data‐based modeling and nonlinear control tools for batch process control
Authors: Aumi Siam , Mhaskar Prashant
Published: July 2011

A data‐based multimodel approach is developed in this work for modeling batch systems in which multiple local linear models are identified using latent variable regression and combined using an appropriate weighting function that arises from fuzzy c‐means clustering. The resulting model is used to generate empirical reverse‐time reachability regions (RTRRs) (defined as the set of states from where the data‐based model can be driven inside a desired end‐point neighborhood of the system), which are subsequently incorporated in a predictive control design. Simulation results of a fed‐batch reactor system under proportional‐integral (PI) control and the proposed RTRR‐based design demonstrate the superior performance of the RTRR‐based design in both a fault‐free and faulty environment. The data‐based modeling methodology is then applied on a nylon‐6,6 batch polymerization process to design a trajectory tracking predictive controller. Closed‐loop simulation results illustrate the superior tracking performance of the proposed predictive controller over PI control. © 2011 American Institute of Chemical Engineers AIChE J, 2012
Validity and reliability of perinatal biomarkers of adiposity after storage as dried blood spots on paper
Authors: Mihalopoulos Nicole L. , Phillips Terry M. , Slater Hillarie , Thomson J. Anne , Varner Michael W. , Nanjee M. Nazeem , Moyer‐Mileur Laurie J.
Published: July 2011

Objective:

To validate use of chip‐based immunoaffinity capillary electrophoresis on dried blood spot samples (DBSS) to measure obesity‐related hormones.

Methods:

Chip‐based immunoaffinity capillary electrophoresis was used to measure adiponectin, leptin and insulin in capillary serum and DBSS in pregnant women and infant heelstick at birth and six weeks. Concordance of measurements was determined with Pearson's correlation and Bland‐Altman plots.

Results:

We report high concordance between results obtained from serum and DBSS.

Conclusions:

Ease of sample collection and storage makes DBSS an optimal method for use in studies involving neonates and young children, as well as studies conducted in areas where freezer storage is not available. Am. J. Hum. Biol., 2011. © 2011 Wiley‐Liss, Inc.
A mixture of buffing dust and chrome shavings as a filler for nitrile rubbers
Authors: Chrońska‐Olszewska K. , Przepiórkowska A.
Published: July 2011

The incorporation of biopolymers, such as chrome shavings and buffing dust, into rubber blends makes it possible to obtain biodecomposable collagen–elastomer materials with good utility properties. It is the presence of a biopolymer in multicomponent polymeric materials that facilitates enzymatic hydrolysis and results in biodecomposition through the loss of cohesiveness and polymer scattering. The undertaking of such original studies was justified by the benefits resulting from a new generation of polymeric materials and the need for a solution to the problem of growing amounts of wastes by waste management in the tanning industry. In this study, the effect of a mixture of chrome shavings and buffing dust on the properties of nitrile rubbers was examined. The dust and shavings, in a 1:1 proportion, were mixed with 5 parts by weight of zinc oxide and, in this form, was added to the rubber blends. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010
Influence of cell structure parameters on the mechanical properties of microcellular polypropylene materials
Authors: Gong Wei , Gao Jiacheng , Jiang Ming , He Li , Yu Jie , Zhu Jianhua
Published: July 2011

Microcellular polypropylene (PP) was prepared through chemical microcellular injection under different processing parameters. The effects of cell structure parameters on the mechanical properties of PP materials were analyzed by the microsphere model. The results show that the mechanical properties of microcellular PP with a smaller cell size and more uniform size distribution were enhanced. The relationship between the mechanical properties and cell structure parameters correlated well with the theoretical model. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Phase state of polyelectrolyte complexes based on blends of acrylic copolymers
Authors: Kiseleva T. I. , Shandryuk G.A. , Khasbiullin R. R. , Shcherbina A. A. , Chalykh A. E. , Feldstein M. M.
Published: July 2011

The phase state of polyelectrolyte blends based on acrylic copolymers was investigated with differential scanning calorimetry, transmission electron microscopy (TEM), and wedge microinterferometry as a function of the blend composition and ionization of polymer functional groups. A copolymer of N,N‐dimethylaminoethyl methacrylate with methyl methacrylate and butyl methacrylate was used as a polybase, a copolymer of methacrylic acid and ethyl acrylate was employed as a polyacid, and the optional plasticizer was triethyl citrate. A correlation was established between an earlier described mechanism of molecular interaction and the behavior of the glass‐transition temperature (Tg) of the polymer blends. The Tg values of the polyelectrolyte complexes in the gel phase were always higher than Tg in the sol phase. This fact implies that intermolecular cohesion dominated the free volume in the stoichiometric polyelectrolyte complexes formed in the gel phase, whereas nonstoichiometric complexes formed in the sol phase were characterized with the predominant contribution of free volume. TEM and interferograms of polyelectrolyte blends showed the signs of anisotropic ordered supramolecular structure formation. A phase‐state diagram of the polyelectrolyte blends was constructed. The stoichiometric polyelectrolyte complex was immiscible with parent polymers, forming a separate phase that became melted at elevation of temperature because of complex dissociation. Polyelectrolyte miscibility was supposed to result rather from the chemical reaction of the complex formation than from interdiffusion of the polymer components along the gradient of their concentration. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
A comprehensive single‐particle model for solid‐state polymerization of poly(L‐lactic acid)
Authors: Katiyar Vimal , Shaama Mallikarjun Sharada , Nanavati Hemant
Published: July 2011

We propose here, a comprehensive model for the solid‐state polymerization (SSP) of a low to moderate molecular weight (MW) prepolymer of lactic acid, to produce high MW poly(L‐lactic acid) (PLLA). The reactions are rationally assumed to occur only in the amorphous region, and effective concentrations of end groups, vary with crystalinity, Xc, during SSP. We estimate byproduct diffusivities, D, using free volume theory. The effects of various parameters on the SSP of PLLA prepolymer have been examined with respect to the optimum MW, Xc and D. We introduce self‐consistently, scaling factors of ∼ 0.27, in the experimental procedure, to determine via 19F‐NMR, concentrations of the end groups, after converting them to fluorinated ester groups. The relevant reaction rate constants are obtained by fitting to early time data from representative SSP experiments at 150°C, under high vacuum, on PLLA prepolymer powder (i.e., spherical geometry) of number average MW, Mn0 ∼ 10,200 Da, which attains Mn ∼ 150,000 Da, via SSP. The subsequent successful comparison of the model predictions with experimental data throughout the entire SSP duration indicates that the model is comprehensive and accounts for all the relevant phenomena occurring during the SSP to synthesize high MW PLLA. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Partition coefficients for a mixture of two lubricant oligomers
Authors: Kanniah Vinod , Forbus T. Reg , Parker Stephanie , Grulke Eric A.
Published: July 2011

Universal base oils that remain pourable over wide temperature ranges would have important advantages for lubrication applications. The model system used in this project was a poly(α‐olefin) synthetic base oil modified with polydimethylsiloxane (PDMS) to lower the pour‐point temperature. Although the blend was miscible at room temperature, phase separation occurred at temperatures lower than 258 K. Partition coefficients of such nonideal oligomer mixtures can (1) help define operating temperature ranges and (2) provide a basis for designing molecular weight distributions of each lubricant that control or prevent phase separation. The poly(α‐olefin) base oil family is branched oligomers with two to five n‐mers at levels greater than 1 wt %, whereas PDMS additives are linear oligomers having between 10 and 50 sequential n‐mers at levels greater than 0.5 wt %. In this study, Fourier transform infrared measurements of the poly(α‐olefin) and PDMS compositions in each phase provided an overall material balance. Poly(α‐olefin) oligomers were detected with size exclusion chromatography with a differential refractive‐index detector, and PDMS oligomers were detected with matrix‐assisted laser desorption/ionization–time‐of‐flight mass spectrometry. The best sets of measurements for the individual oligomers in each phase were selected by minimization of the overall material balance errors. For both oligomers, components with high molecular weights were preferentially excluded from the phase rich in the other polymer and were relatively independent of temperature. The partition coefficients of poly(α‐olefin) components increased with increasing oligomer length, whereas the partition coefficients of the PDMS components decreased with increasing oligomer length. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Synthesis of a chiral stationary phase with poly[styrene‐b‐cellulose 2,3‐bis(3,5‐dimethylphenylcarbamate)] by surface‐initiated atom transfer radical polymerization and its chiral resolution efficiency
Authors: Yang Ji‐Hoon , Choi Seong‐Ho
Published: July 2011

A chiral stationary phase (CSP) with poly[styrene‐b‐cellulose 2,3‐bis(3,5‐dimethylphenylcarbamate)] was synthesized by the surface‐initiated atom transfer radical polymerization (SI‐ATRP) of cellulose 2,3‐bis(3,5‐dimethylphenylcarbamate)‐6‐acrylate after the SI‐ATRP of styrene on the surface of silicon dioxide supports in pyridine. The successful preparation of the CSP with poly[styrene‐b‐cellulose 2,3‐bis(3,5‐dimethylphenylcarbamate)] was confirmed via Fourier transform infrared spectroscopy, field emission scanning electron microscopy, X‐ray photoelectron spectroscopy, elemental analysis, and thermal analysis. The applicability for the chiral resolution of the CSP with poly[styrene‐b‐cellulose 2,3‐bis(3,5‐diphenylcarbamate)] was evaluated with high‐performance liquid chromatography with 10 racemates under various mobile phases of hexane/alcohol, hexane/tetrahydrofuran (THF), and hexane/chloroform. The results show that the CSP with poly[styrene‐b‐cellulose 2,3‐bis(3,5‐diphenylcarbamate)] could be used in THF and chloroform as eluents. The chiral resolutions of the commercial Chiracel OD, the CSP with cellulose 2,3‐bis(3,5‐dimethylphenylcarabmate), and the CSP with poly[styrene‐b‐cellulose 2,3‐bis(3,5‐dimethylphenylcarbamate)] prepared by SI‐ATRP were examined. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Diffusion of levofloxacin mesylate in agarose hydrogels monitored by a refractive‐index method
Authors: Dai Hongjun , Wu Junjie , Wang Yongxin , Tan Shuaixia , Liang Songmiao , Jiang Bin , Zhao Ning , Xu Jian
Published: July 2011

The diffusion of levofloxacin mesylate (MSALVFX) within agarose hydrogels was investigated by an improved refractive‐index method. The diffusion coefficient of MSALVFX in infinite dilution (D0) was obtained as 4.01 × 10−6 cm2/s (25°C) through extrapolation according to Kohlrausch's law. The diffusion behavior of MSALVFX under conditions of different solute concentrations, polymer volume fractions, and temperatures was studied in detail. In the considered range of agarose concentrations (0.5–2.5%, w/w), the ratio of Dg to D0 (where Dg is the effective diffusion coefficient of MSALVFX in the agarose hydrogel) decreased from 0.938 to 0.835 because of the retardance effect of agarose fiber. Furthermore, the experimental data were analyzed with the Amsden, Clague and Philips, and Ogston models, and the data fit the Amsden model best. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Preparation and crystallization behavior of poly(vinylidene fluoride‐ter‐chlorotrifluoroethylene‐ ter‐trifluoroethylene)
Authors: Li Hengfeng , Tan Kaiyuan , Hao Zeming , He Guowen
Published: July 2011

Several poly(vinylidene fluoride‐ter‐chlorotrifluoroethylene‐ter‐trifluoroethylene) terpolymers, including 68 mol % vinylidene fluoride, were prepared by the partial reduction of chlorine in poly(vinylidene fluoride‐co‐chlorotrifluoroethylene) copolymers. The terpolymers were then allowed to crystallize under two sets of conditions: (1) crystallized from solution (in N,N‐dimethylformamide) at 35°C for 108 h and (2) annealed at temperatures 5°C below their respective melting points for 11 h. The effect of the chlorotrifluoroethylene (CTFE) content and crystallization conditions on the crystallization behavior of the terpolymers was investigated by X‐ray diffraction, Fourier transform infrared spectroscopy, and differential scanning calorimetry. The results show that with increasing CTFE content, the terpolymers contained less of the β phase (it even disappeared), which had an all‐trans chain conformation, and more of the γ phase was found, which became prominent with the trans–trans–trans–gauche conformation. The crystallinity, crystal size, fusion enthalpy, and melting temperatures of the terpolymers decreased with increasing CTFE content. Compared with annealed terpolymers, the terpolymers crystallized from the solution at 35°C included more polar components that contained more trans conformations but had lower crystallinities, melting temperatures, and fusion enthalpies and smaller crystal sizes. These results suggest that crystallization from the solution may be helpful in forming polar crystals, whereas an annealing process at a high temperature is beneficial in perfecting the crystal structure. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Preparation of monodispersed and lipophilic attapulgite and polystyrene nanorods via surface‐initiated atom transfer radical polymerization
Authors: Zhang Hong , Ye Weichun , Zhou Feng
Published: July 2011

A new kind of initiator, 3‐(2‐bromo‐2‐methylacryloxy)propyltriethysiliane (MPTS‐Br), was prepared with a simply hydrobrominated commercial silane coupling agent (3‐methacryloxy‐proplytriethysilane, MPTS). It has been one‐step self‐assemble onto the surface of attapulgite (ATP) nanorods in the dispersion system, and by using this initiator‐modified nanorod (MPTS‐Br‐modified ATP nanoparticles, ATP‐MPTS‐Br) as macroinitiator for atom transfer radical polymerization (ATRP). Structurally well‐defined homopolymer polystyrene (PS) and block polymer poly(styrene‐b‐methyl methacrylate) (PS‐b‐PMMA) chains were then grown from the needle‐shaped nanorods surface to yield monodispersed nanorods composed of ATP core and thick‐coated polymer shell (ATP and PS). The graft polymerization parameters exhibited the characteristics of a controlled/”living” polymerization. The PS‐grafted ATP nanorods could be dispersed well in organic solvent with nanoscale. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
The effect of isopropanol addition on enhancement of transdermal controlled release of ibuprofen from ethylene vinyl acetate copolymer membranes
Authors: Emami Shahriar Hojjati , Pirbasti Zahra Hassannejad , Hasani‐Sadrabadi Mohammad Mahdi , Kordestani Soheila S.
Published: July 2011

This work reports the study of the addition of isopropanol on controlled release of ibuprofen from ethylene vinyl acetate (EVAc) copolymer membranes. An EVAc solution in cyclohexane (4% w/v) containing triethyl citrate (7% w/v) as plasticizer was mixed with ibuprofen at three different concentrations of 4, 6, and 8%. Isopropanol was mixed with each of the previous mixtures to form solutions of 1, 3, and 5% isopropanol concentrations. Samples were solvent cast on glass petri‐dishes to form membranes. Home‐made diffusion cells were used for in vitro study. These cells were composed of two compartments, donor (exposed to ambient conditions), and receptor (including buffer solution maintained at 37°C). Each cell was equipped with a sampling port and water in and out system. An ultraviolet spectrometer at 222 nm was used to measure release rates of obtained membranes. The diffusion mechanism for drug release was examined by zero‐order, first‐order, Higuchi and Korsmeyer‐Peppas theories to confirm the obtained membranes follow the matrix‐type system. By increasing the drug concentration from 4 to 8%, drug release (cumulative amount) was improved from 20 (47.5%) to 30 (36%) μg/cm2 after 24 h. Addition of 5% isopropanol to the above samples (4 and 8% loading) further increased drug release to 24 and 43 μg/cm2. Results were in good agreement with the Korsmeyer‐Peppas theory for samples with 4 (% w/w) of ibuprofen. The highest percentage of drug release after 24 h was 59% for the sample with 4% drug loading compared to 50% for the sample with 8% drug loading, both with 5% isopropanol. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Viscoelastic behavior of polymer tape in a wound roll
Authors: Acton Katherine , Weick Brian
Published: July 2011

A viscoelastic computational model is developed that uses experimentally determined viscoelastic material properties as input and can be used to predict the behavior of a tape material in a wound roll as stresses relax over time. Experimental creep test results are used to find best‐fit creep‐compliance parameters to describe two high density data storage tape media. The two tapes used in the analysis are a developmental tape with a poly(ethylenenaphthalate) (PEN) substrate and metal particle (MP) front coat similar to linear tape open (LTO4) (referred to in this work as “Tape C”), and LTO3, a commercially available tape with a PEN substrate and MP front coat. Sets of best‐fit creep‐compliance parameters are determined for both tapes. The differences between the predicted behavior using three‐, five‐, and seven‐parameter Kelvin–Voigt models are evaluated, both for a benchmark case and in a viscoelastic wound roll model. The choice of material model is found to significantly influence the predictions of the wound roll model. The differences between different material models for the same material are on the order of the differences found between the two different materials. A material model with a higher number of creep‐compliance parameters, although more computationally expensive, produces better results, particularly over long spans of time. The relative differences between the three‐, five‐, and seven‐parameter models are shown to be qualitatively consistent for several variations in the computational model setup, allowing predictions to be made based on simple benchmarks. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Conservation status of the world's hagfish species and the loss of phylogenetic diversity and ecosystem function
Authors: Knapp Landon , Mincarone Michael M. , Harwell Heather , Polidoro Beth , Sanciangco Jonnell , Carpenter Kent
Published: July 2011

Hagfishes represent an ancient and unique evolutionary lineage that plays an important role in the cycling of organic matter and other nutrients to maintain the overall health of the ecosystems they inhabit.

Fisheries worldwide directly profit from the harvesting of hagfishes for leather and food, as well as from the positive habitat effects hagfishes provide for other target species. Overexploitation and destructive fishing practices are major threats to several hagfish species, especially those with restricted or small distributions.

In order to evaluate the effect of these threats on populations, the International Union for Conservation of Nature (IUCN) Red List Categories and Criteria were applied to assess the probability of extinction for all of the world's known hagfish species.

Nine of the 76 hagfish species (12%) were determined to be in threatened categories, indicating an elevated risk of extinction. Particular areas and species of concern include southern Australia where 100% of hagfish species present were determined to be at an elevated risk of extinction and the coast of southern Brazil where up to 50% of hagfish species present are at an elevated risk of extinction. Also of concern, are the species found in the East China Sea, Pacific coast of Japan, and coastal Taiwan where as many as 50% of hagfish species are threatened with extinction.

The loss of hagfish species will have detrimental effects on ecosystems as a whole as well as the fisheries that depend on them, especially in the many areas around the world that have low hagfish species diversity.

Better information, data, regulation and management of hagfish fisheries and other threats to hagfish populations are urgently needed to ensure the survival of these important species.

Copyright © 2011 John Wiley & Sons, Ltd.
Demystifying the Millennial student: A reassessment in measures of character and engagement in professional education
Authors: DiLullo Camille , McGee Patricia , Kriebel Richard M.
Published: July 2011

The characteristic profile of Millennial Generation students, driving many educational reforms, can be challenged by research in a number of fields including cognition, learning style, neurology, and psychology. This evidence suggests that the current aggregate view of the Millennial student may be less than accurate. Statistics show that Millennial students are considerably diverse in backgrounds, personalities, and learning styles. Data are presented regarding technological predilection, multitasking, reading, critical thinking, professional behaviors, and learning styles, which indicate that students in the Millennial Generation may not be as homogenous in fundamental learning strategies and attitudes as is regularly proposed. Although their common character traits have implications for instruction, no available evidence demonstrates that these traits impact their fundamental process of learning. Many curricular strategies have been implemented to address alleged changes in the manner by which Millennial students learn. None has clearly shown superior outcomes in academic accomplishments or developing expertise for graduating students and concerns persist related to the successful engagement of Millennial students in the process of learning. Four factors for consideration in general curricular design are proposed to address student engagement and optimal knowledge acquisition for 21st century learners. Anat Sci Educ 4: 214‐226. © 2011 American Association of Anatomists.
Tuning the Excited State of Photoactive Building Blocks for Metal‐Templated Self‐Assembly
Authors: Ahmad Haslina , Meijer Anthony J. H. M. , Thomas Jim A.
Published: July 2011

The reaction of 2,2′:4,4′′:4′,4′′′‐quaterpyridyl (qtpy), with d6 ruthenium(II) (RuII), and rhenium(I) (ReI) metal centers has been investigated. The pendant pyridyl groups on the products have also been methylated to produce a second series of complexes containing coordinated Meqtpy2+. The absorption spectra of the complexes are dominated by intraligand and charge‐transfer bands. The ruthenium(II) complexes display broad unstructured luminescence consistent with emission from a Ru(d)→diimine(π*) manifold in acetonitrile solutions. In aqueous solutions, their emissions are weaker and the lifetimes are shorter. This effect is particularly acute for complexes incorporating coordinated dipyridylpyrazine, dppz, ligands. Although the emission of the ruthenium(II) complexes containing Meqtpy2+ is generally shorter than their qtpy analogs, it is notable that solvent‐dependent effects are much less intense. The rhenium(I) complexes also display broad unstructured luminescence but, compared with the ruthenium(II) systems, they have a relatively short lifetime in acetonitrile. Electrochemical studies reveal that all of the RuII complexes display chemically reversible metal‐based oxidations. ReI complexes only display irreversible metal‐based oxidations. In most cases, the reduction processes were not fully chemically reversible. The electrochemical and optical studies reveal that the nature of the lowest excited state of these complexes—particularly, the systems incorporating dppz—is highly dependent on the nature of the coordinated ligands. Calculations indicate that, although the excited state of most of the complexes is centered on the qtpy or Meqtpy2+ ligands, the excited state of the complexes containing dppz ligands is switched away from the dppz by qtpy methylation. A crystallographic study on one of the dicationic ruthenium(II) structures reveals that it forms an inclusion complex with benzene.
Advanced Regional Biomass Processing Depots: a key to the logistical challenges of the cellulosic biofuel industry
Authors: Eranki Pragnya L. , Bals Bryan D. , Dale Bruce E.
Published: July 2011

Interest in commercially viable cellulosic biofuel production has greatly increased due to concerns regarding the sustainability of petroleum fuels. While research into solving the technical issues surrounding cellulosic biofuels is ongoing, much less attention has been paid to solving supply chain challenges such as low bulk density of cellulosic biomass, compositional variability and seasonality of the feedstock, food vs fuel issues, and local environmental concerns. To address these supply chain problems, we explore the concept of Regional Biomass Processing Depots (RBPDs), strategically distributed facilities that procure, pre‐process /pre‐treat and densify biomass into stable intermediate products that are compatible with existing bulk commodity logistical systems. In this perspective, we discuss the fundamental concept of RBPDs, their functionality, advantages, and potential challenges. We then extend the analysis of depots to include enhanced configurations and discuss some technologies that might be deployed in RBPD networks and the valuable coproducts that might be produced via synergies among these technologies. © 2011 Society of Chemical Industry and John Wiley & Sons, Ltd
Probiotics function mechanistically as delivery vehicles for neuroactive compounds: Microbial endocrinology in the design and use of probiotics
Authors: Lyte Mark
Published: July 2011

I hypothesize here that the ability of probiotics to synthesize neuroactive compounds provides a unifying microbial endocrinology‐based mechanism to explain the hitherto incompletely understood action of commensal microbiota that affect the host's gastrointestinal and psychological health. Once ingested, probiotics enter an interactive environment encompassing microbiological, immunological, and neurophysiological components. By utilizing a trans‐disciplinary framework known as microbial endocrinology, mechanisms that would otherwise not be considered become apparent since any candidate would need to be shared among all three components. The range of neurochemicals produced by probiotics includes neurochemicals for which receptor‐based targets on immune and neuronal elements (intestinal and extra‐intestinal) have been well characterized. Production of neurochemicals by probiotics therefore allows for their consideration as delivery vehicles for neuroactive compounds. This unifying microbial endocrinology‐based hypothesis, which may facilitate the selection and design of probiotics for clinical use, also highlights the largely unrecognized role of neuroscience in understanding how microbes may influence health.

Editor's suggested further reading in BioEssays Harvesting the biological potential of the human gut microbiome Abstract
Middle aortic syndrome with renal involvement: A staged strategy to manage systemic hypertension
Authors: Morgan Gareth , Benson Lee , Geary Denis
Published: July 2011

Long segment narrowing of the thoracoabdominal aorta or so‐called middle aortic syndrome (MAS), is an uncommon lesion presenting variably with physical signs of coarctation of the aorta, hypertension, renal insufficiency and or mesenteric ischemia. The etiologies are multiple, but Takayasu's arteritis is a leading cause. Variable involvement of diverse systemic arterial systems requires individualized management strategies. We report a case of a successful treatment algorithm for severe MAS using a strategy of percutaneous aortic endovascular stent implantation to rebuild the distal aorta and renal auto‐implantation to address systemic hypertension. © 2011 Wiley Periodicals, Inc.
Retroperitoneal hemorrhage after percutaneous coronary intervention in the current practice era: Clinical outcomes and prognostic value of abdominal/pelvic computed tomography
Authors: Maluenda Gabriel , Mitulescu Lavinia , Ben‐Dor Itsik , A. Gaglia Michael , Weissman Gaby , Torguson Rebecca , F. Satler Lowell , Pichard Augusto D. , Bernardo Nelson L. , Waksman Ron
Published: July 2011

Background: Retroperitoneal hemorrhage (RPH) is a serious but infrequent complication of percutaneous coronary intervention (PCI). This study aimed to describe the clinical outcomes of patients who developed RPH following PCI in the current practice era, with particular focus on treatment strategies and the related prognostic value of abdominal/pelvic computed tomography (CT). Methods: Among 20,904 patients undergoing PCI, we identified 93 RPH (0.45%) confirmed by CT or by unequivocal surgical findings. We identified three groups with RPH for comparison: patients who developed refractory shock (systolic blood pressure <80 mm Hg for ≥30 min despite fluids and vasopressors, n = 16 [17.2%]); patients with transient hypotension (<30 min, n = 34 [36.6%]); and patients without hypotension (n = 43 [46.2%]). The primary endpoint was a composite of in‐hospital mortality, myocardial infarction, and cerebral vascular accident (CVA). Results: Baseline clinical, angiographic, and procedural characteristics were similar among the three groups. Patients who developed refractory shock had significantly more bleeding quantified by abdominal/pelvic CT (P < 0.001), had a higher rate and amount of red blood cell transfusion (P < 0.001), and were managed invasively more frequently (68.7%) than the rest of the population. The primary endpoint trended higher in patients presenting with refractory shock; however, this difference was not statistically significant. The volume of bleeding quantified by CT and the timing of imaging diagnosis did not correlate with the primary endpoint. Red blood cell transfusion, but not clopidogrel discontinuation, was associated with the primary endpoint. Conclusions: RPH remains as a serious complication of PCI and is associated with high rates of mortality and morbidity independently of the therapeutic strategy. In patients who were hemodynamically stable, RPH volume as quantified by non‐contrast abdominal/pelvic CT did not contribute to prognosis. © 2011 Wiley Periodicals, Inc.
Incomplete arterial healing 8 years after the implantation of sirolimus‐eluting stent. In vivo visualization by optical coherence tomography
Authors: Bouki Konstantina P. , Sakkali Eleni K. , Apostolou Thomas S.
Published: July 2011

The time course of complete arterial healing after drug eluting stent implantation is unknown. We present a case of incomplete endothelialization and late stent malapposition identified by optical coherence tomography 8 years after a sirolimus‐eluting stent implantation, which was not related with any adverse clinical event. © 2011 Wiley Periodicals, Inc.