bluuebunny/crossref_metadata_2025 huggingface dataset:
Amylin deposition in the brain: A second amyloid in Alzheimer disease?
Authors: Jackson Kaleena , Barisone Gustavo A. , Diaz Elva , Jin Lee‐way , DeCarli Charles , Despa Florin
Published: June 2013

Objective

Hyperamylinemia, a common pancreatic disorder in obese and insulin‐resistant patients, is known to cause amylin oligomerization and cytotoxicity in pancreatic islets, leading to β‐cell mass depletion and development of type 2 diabetes. Recent data has revealed that hyperamylinemia also affects the vascular system, heart, and kidneys. We therefore hypothesized that oligomerized amylin might accumulate in the cerebrovascular system and brain parenchyma of diabetic patients.

Methods

Amylin accumulation in the brain of diabetic patients with vascular dementia or Alzheimer disease (AD), nondiabetic patients with AD, and age‐matched healthy controls was assessed by quantitative real time polymerase chain reaction, immunohistochemistry, Western blot, and enzyme‐linked immunosorbent assay.

Results

Amylin oligomers and plaques were identified in the temporal lobe gray matter from diabetic patients, but not controls. In addition, extensive amylin deposition was found in blood vessels and perivascular spaces. Intriguingly, amylin deposition was also detected in blood vessels and brain parenchyma of patients with late onset AD without clinically apparent diabetes. Mixed amylin and amyloid β (Aβ) deposits were occasionally observed. However, amylin accumulation leads to amyloid formation independent of Aβ deposition. Tissues infiltrated by amylin showed increased interstitial space, vacuolation, spongiform change, and capillaries bent at amylin accumulation sites. Unlike the pancreas, there was no evidence of amylin synthesis in the brain.

Interpretation

Metabolic disorders and aging promote accumulation of amylin amyloid in the cerebrovascular system and gray matter, altering microvasculature and tissue structure. Amylin amyloid formation in the wall of cerebral blood vessels may also induce failure of elimination of Aβ from the brain, thus contributing to the etiology of AD. Ann Neurol 2013;74:517–526
Pituitary dysfunction after blast traumatic brain injury
Authors: Baxter David , Sharp David J. , Feeney Claire , Papadopoulou Debbie , Ham Timothy E. , Jilka Sagar , Hellyer Peter J. , Patel Maneesh C. , Bennett Alexander N. , Mistlin Alan , McGilloway Emer , Midwinter Mark , Goldstone Anthony P.
Published: June 2013

Objective

Pituitary dysfunction is a recognized consequence of traumatic brain injury (TBI) that causes cognitive, psychological, and metabolic impairment. Hormone replacement offers a therapeutic opportunity. Blast TBI (bTBI) from improvised explosive devices is commonly seen in soldiers returning from recent conflicts. We investigated: (1) the prevalence and consequences of pituitary dysfunction following moderate to severe bTBI and (2) whether it is associated with particular patterns of brain injury.

Methods

Nineteen male soldiers with moderate to severe bTBI (median age = 28.3 years) and 39 male controls with moderate to severe nonblast TBI (nbTBI; median age = 32.3 years) underwent full dynamic endocrine assessment between 2 and 48 months after injury. In addition, soldiers had structural brain magnetic resonance imaging, including diffusion tensor imaging (DTI), and cognitive assessment.

Results

Six of 19 (32.0%) soldiers with bTBI, but only 1 of 39 (2.6%) nbTBI controls, had anterior pituitary dysfunction (p = 0.004). Two soldiers had hyperprolactinemia, 2 had growth hormone (GH) deficiency, 1 had adrenocorticotropic hormone (ACTH) deficiency, and 1 had combined GH/ACTH/gonadotrophin deficiency. DTI measures of white matter structure showed greater traumatic axonal injury in the cerebellum and corpus callosum in those soldiers with pituitary dysfunction than in those without. Soldiers with pituitary dysfunction after bTBI also had a higher prevalence of skull/facial fractures and worse cognitive function. Four soldiers (21.1%) commenced hormone replacement(s) for hypopituitarism.

Interpretation

We reveal a high prevalence of anterior pituitary dysfunction in soldiers suffering moderate to severe bTBI, which was more frequent than in a matched group of civilian moderate to severe nbTBI subjects. We recommend that all patients with moderate to severe bTBI should routinely have comprehensive assessment of endocrine function. Ann Neurol 2013;74:527–536
Solvent‐Dependent Reversible Ligand Exchange in Nickel Complexes of a Monosulfide Bis(diphenylphosphino)(N‐thioether)amine
Authors: Ghisolfi Alessio , Fliedel Christophe , Rosa Vitor , Pattacini Roberto , Thibon Aurore , Yu. Monakhov Kirill , Braunstein Pierre
Published: June 2013

The coordination chemistry of the DPPA‐type functional phosphine bis(diphenylphosphino)(N‐thioether)amine N(PPh2)2(CH2)3SMe (1) and its monosulfide derivative, (Ph2P)N{P(S)Ph2}(CH2)3SMe (1⋅S), towards NiII precursors has been investigated. The crystal structures of N{P(S)Ph2}2(CH2)3SMe (1⋅S2), [NiCl2{(Ph2P)2N(CH2)3SMe‐P,P}] (2), [NiCl2((Ph2P)N{P(S)Ph2}(CH2)3SMe‐P,S)] (3), [Ni((Ph2P)N{P(S)Ph2}(CH2)3SMe‐P,S)2]NiCl4 (3′), [Ni((Ph2P)N{P(S)Ph2}(CH2)3SMe‐P,S)2](BF4)2 (4), and [Ni((Ph2P)NH{P(S)Ph2}‐P,S)2]Cl2 (5) have been determined by single‐crystal X‐ray diffraction. In all of the complexes with the hybrid ligand 1⋅S, P,S‐chelation to the NiII center is observed. Despite the stability generally associated with five‐membered ring chelation, easy migration of this LL′‐type P,S‐chelating ligand from one metal center to another was observed, which accounts for the reversible ligand‐redistribution reaction occurring in the equilibrium between the neutral, diamagnetic complex [NiCl2LL′] and the paramagnetic ion‐pair [Ni(LL′)2][NiCl4]. Detailed investigations by multinuclear NMR, UV/Vis, and FTIR spectroscopic methods and DFT calculations are reported. Each of the formula isomers 3 and 3′ can be selectively obtained, depending on the experimental conditions.
Biochemical characterization and crystal structure of a GH10 xylanase from termite gut bacteria reveal a novel structural feature and significance of its bacterial Ig‐like domain
Authors: Han Qian , Liu Ning , Robinson Howard , Cao Lin , Qian Changli , Wang Qianfu , Xie Lei , Ding Haizhen , Wang Qian , Huang Yongping , Li Jianyong , Zhou Zhihua
Published: June 2013

Bacterial Ig‐like (Big) domains are commonly distributed in glycoside hydrolases (GH), but their structure and function remains undefined. Xylanase is a GH, and catalyzes the hydrolysis of the internal β‐xylosidic linkages of xylan. In this study, we report the molecular cloning, biochemical and biophysical characterization, and crystal structure of a termite gut bacterial xylanase, Xyl‐ORF19, which was derived from gut bacteria of a wood‐feeding termite (Globitermes brachycerastes). The protein architecture of Xyl‐ORF19 reveals that it has two domains, a C‐terminal GH10 catalytic domain and an N‐terminal Big_2 non‐catalytic domain. The catalytic domain folds in an (α/β)8 barrel as most GH10 xylanases do, but it has two extra β‐strands. The non‐catalytic domain is structurally similar to an immunoglobulin‐like domain of intimins. The recombinant enzyme without the non‐catalytic domain has fairly low catalytic activity, and is different from the full‐length enzyme in kinetic parameters, pH and temperature profiles, which suggests the non‐catalytic domain could affect the enzyme biochemical and biophysical properties as well as the role for enzyme localization. This study provides a molecular basis for future efforts in xylanase bioengineering. Biotechnol. Bioeng. 2013;110: 3093–3103. © 2013 Wiley Periodicals, Inc.
Hydrolytically degradable poly(ethylene glycol) hydrogel scaffolds as a cell delivery vehicle: Characterization of PC12 cell response
Authors: Zustiak Silviya P. , Pubill Stephanie , Ribeiro Andreia , Leach Jennie B.
Published: June 2013

The central nervous system (CNS) has a low intrinsic potential for regeneration following injury and disease, yet neural stem/progenitor cell (NPC) transplants show promise to provide a dynamic therapeutic in this complex tissue environment. Moreover, biomaterial scaffolds may improve the success of NPC‐based therapeutics by promoting cell viability and guiding cell response. We hypothesized that a hydrogel scaffold could provide a temporary neurogenic environment that supports cell survival during encapsulation, and degrades completely in a temporally controlled manner to allow progression of dynamic cellular processes such as neurite extension. We utilized PC12 cells as a model cell line with an inducible neuronal phenotype to define key properties of hydrolytically degradable poly(ethylene glycol) hydrogel scaffolds that impact cell viability and differentiation following release from the degraded hydrogel. Adhesive peptide ligands (RGDS, IKVAV, or YIGSR), were required to maintain cell viability during encapsulation; as compared to YIGSR, the RGDS, and IKVAV ligands were associated with a higher percentage of PC12 cells that differentiated to the neuronal phenotype following release from the hydrogel. Moreover, among the hydrogel properties examined (e.g., ligand type, concentration), total polymer density within the hydrogel had the most prominent effect on cell viability, with densities above 15% w/v leading to decreased cell viability likely due to a higher shear modulus. Thus, by identifying key properties of degradable hydrogels that affect cell viability and differentiation following release from the hydrogel, we lay the foundation for application of this system towards future applications of the scaffold as a neural cell delivery vehicle. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29:1255–1264, 2013
Metabolic engineering and transhydrogenase effects on NADPH availability in escherichia coli
Authors: Jan Joanna , Martinez Irene , Wang Yipeng , Bennett George N. , San Ka‐Yiu
Published: June 2013

The synthesis of several industrially useful compounds are cofactor‐dependent, requiring reducing equivalents like NADPH in enzymatic reactions leading up to the synthesis of high‐value compounds like polymers, chiral alcohols, and antibiotics. However, NADPH is costly and has limited intracellular availability. This study focuses on the study of the effect of the two transhydrogenase enzymes of Escherichia coli, PntAB and UdhA (SthA) on reducing equivalents‐dependent biosynthesis. The production of (S)‐2‐chloropropionate from 2‐chloroacrylate is used as a model system for monitoring NADPH availability because 2‐haloacrylate reductase, the enzyme catalyzing the one‐step conversion to (S)‐2‐chloropropionate in the synthesis pathway, requires NADPH as a cofactor. Results suggest that the presence of UdhA increases product yield and NADPH availability while the presence of PntAB has the opposite effect. A maximum product yield of 1.4 mol product/mol glucose was achieved aerobically in a pnt‐deletion strain with udhA overexpression, a 150% improvement over the wild‐type control strain. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29:1124–1130, 2013
Interactions between l‐arginine/l‐arginine derivatives and lysozyme and implications to their inhibition effects on protein aggregation
Authors: Gao Ming‐Tao , Dong Xiao‐Yan , Sun Yan
Published: June 2013

l‐Arginine (Arg), l‐homoarginine (HArg), l‐arginine ethylester (ArgEE), and l‐arginine methylester (ArgME) were found effective in inhibiting protein aggregation, but the molecular mechanisms are not clear. Herein, stopped‐flow fluorescence spectroscopy, isothermal titration calorimetry, and mass spectroscopy were used to investigate the folding kinetics of lysozyme and the interactions of the additives with lysozyme. It was found that the interactions of ArgME and ArgEE with lysozyme were similar to that of guanidine hydrochloride and were much stronger than those of Arg and HArg. The binding forces were all mainly hydrogen bonding and cation‐π interaction from the guanidinium group, but their differences in molecular states led to the significantly different binding strengths. The additives formed molecular clusters in an increasing order of ArgEE, ArgME, HArg, and Arg. Arg and HArg mainly formed annular clusters with head‐to‐tail bonding, while ArgME and ArgEE formed linear clusters with guanidinium groups stacking. The interactions between the additives and lysozyme were positively related to the monomer contents. That is, the monomers were the primary species that participated in the direct interactions due to their intact guanidinium groups and small sizes, while the clusters performed as barriers to crowd out the protein–protein interactions for aggregation. Thus, it is concluded that the effects of Arg and its derivatives on protein aggregation stemmed from the direct interactions by the monomers and the crowding effects by the clusters. Interplay of the two effects led to the differences in their inhibition effects on protein aggregation. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29:1316–1324, 2013
Synthesis of Methanethiol from CS2 on Ni‐, Co‐, and K‐Doped MoS2/SiO2 Catalysts
Authors: Gutiérrez Oliver Y. , Zhong Liangshu , Zhu Yongzhong , Lercher Johannes A.
Published: June 2013

The synthesis of methanethiol from CS2 catalyzed by Ni‐, Co‐, or K‐modified MoS2/SiO2 through the sequence CS2→CH3SH→CH3SCH3 (DMS) has been studied. CS2 is readily hydrogenated to CH3SH, whereas CH3SH and DMS decompose to CH4 at high CS2 conversions and temperatures. Thus, very high yields of CH3SH can be obtained on all the catalysts. The addition of Co or Ni accelerates all reaction steps to allow the formation of CH3SH under relatively mild conditions. On the contrary, K suppresses the formation of byproducts but also lowers the activity. The surface reaction proceeds through a series of hydrogen‐addition steps, the rate‐controlling step of which is the addition of the first H atom. H2 adsorbs dissociatively, whereas CS2 adsorbs strongly in a single active site prior to hydrogenation. The addition of Ni has a stronger enhancing effect on hydrogenation and accelerates the CS bond cleavage to a smaller extent than Co. Therefore, Ni leads to optimum CH3SH yields and holds the best promise as promoter for the MoS2 phase in the synthesis of methanethiol from CS2.
Chiral Thin Films of Metal Oxide
Authors: Moshe Hagay , Vanbel Maarten , Valev Ventsislav Kolev , Verbiest Thierry , Dressler David , Mastai Yitzhak
Published: June 2013

In this paper, we describe for the first time the synthesis of new chiral nanosized metal oxide surfaces based on chiral self‐assembled monolayers (SAMs) coated with metal oxide (TiO2) nanolayers. In this new type of nanosize chiral surface, the metal oxide nanolayers enable the protection of the chiral self‐assembled monolayers while preserving their enantioselective nature. The chiral nature of the SAM/TiO2 films was characterized by variety of unique techniques, such as second‐harmonic generation circular dichroism (SHG‐CD), quartz crystal microbalance, and chiral adsorption measurements with circular dichroism spectroscopy. The chiral resolution abilities of the SAMs coated with metal oxide (TiO2) nanolayers were investigated in the crystallization of a racemic mixture of threonine and glutamic acid. Our proposed methodology for the preparation of nanoscale chiral surfaces described in this article could open up opportunities in other fields of chemistry, such as chiral catalysis.
Importance of Size and Distribution of Ni Nanoparticles for the Hydrodeoxygenation of Microalgae Oil
Authors: Song Wenji , Zhao Chen , Lercher Johannes A.
Published: June 2013

Improved synthetic approaches for preparing small‐sized Ni nanoparticles (d=3 nm) supported on HBEA zeolite have been explored and compared with the traditional impregnation method. The formation of surface nickel silicate/aluminate involved in the two precipitation processes are inferred to lead to the stronger interaction between the metal and the support. The lower Brønsted acid concentrations of these two Ni/HBEA catalysts compared with the parent zeolite caused by the partial exchange of Brønsted acid sites by Ni2+ cations do not influence the hydrodeoxygenation rates, but alter the product selectivity. Higher initial rates and higher stability have been achieved with these optimized catalysts for the hydrodeoxygenation of stearic acid and microalgae oil. Small metal particles facilitate high initial catalytic activity in the fresh sample and size uniformity ensures high catalyst stability.
Correction of single‐beam sample absorption error in a hemispherical 45°/0° spectrophotometer measurement cavity
Authors: Sloan Walter W.
Published: June 2013

A mathematical model for quantifying single‐beam sample absorption error in a hemispherical 45°/0° measurement cavity is derived and tested by measuring diffuse reflectance standards with a prototype visible‐range spectrophotometer. A methodology is described for using this three‐parameter model to correct for sample absorption error in any single‐beam spectrophotometer. © 2013 Wiley Periodicals, Inc. Col Res Appl, 39, 436–441, 2014
Correlation and modeling between color variation and quality of the surface between accelerated and natural tropical weathering in Acacia mangium, Cedrela odorata and Tectona grandis wood with two coating
Authors: Valverde Juan Carlos , Moya Róger
Published: June 2013

To prevent the photodegradation process, a wide range of coatings have been developed. This study evaluated wood color change (ΔE*) and the surface quality index (SQI) generated by ASTM D‐660 standards in wood protected with polyurethane and varnish finishes of three tropical species (Acacia mangium, Cedrela odorata and Tectona grandis) in two weathering conditions (natural and accelerated condition). In addition, a model was developed to predict ΔE* and SQI in natural weathering based on ΔE* and SQI from accelerated weathering. The results showed that the application of these finishes generated variations in the color parameters of wood before being exposed to the elements. Additionally, it was found that finishes generated increases in ΔE*, especially the varnish type finish, and decreasing of SQI. Finally, models were found to predict color changes or surface quality in natural weathering based on color changes or surface quality in accelerated weathering. The model algorithm was expressed by ΔE* or SQI measured (X) and time exposure (t) in accelerated weathering by equation
. With these models, it is possible to predict the equivalence of exposure times in natural weathering in tropical conditions for different kinds of finishes in three tropical species. © 2013 Wiley Periodicals, Inc. Col Res Appl, 39, 519–529, 2014
High‐Dimensional NMR Spectra for Structural Studies of Biomolecules
Authors: Kazimierczuk Krzysztof , Stanek Jan , Zawadzka‐Kazimierczuk Anna , Koźmiński Wiktor
Published: June 2013

Recent developments in the acquisition and processing of NMR data sets facilitate the recording of ultra‐high‐resolution NMR spectra in a reasonable time. The new experiments allow easy resonance assignment for folded and unfolded proteins, as well as the precise determination of spectral parameters, for example, chemical shifts, NOE contacts, coupling constants or cross‐correlated relaxation rates. Owing to exceptional resolution of 4D–6D spectroscopy, detailed studies of biomolecules of unprecedented complexity are now possible. Herein, the principles of acquisition and processing methods are presented. The main applications of high‐dimensional NMR experiments, including backbone and side‐chain resonance assignment in proteins, as well as heteronuclear edited NOE techniques are reviewed.
Genetic structure of wildcat (Felis silvestris) populations in Italy
Authors: Mattucci F. , Oliveira R. , Bizzarri L. , Vercillo F. , Anile S. , Ragni B. , Lapini L. , Sforzi A. , Alves P. C. , Lyons L. A. , Randi E.
Published: June 2013

Severe climatic changes during the Pleistocene shaped the distributions of temperate‐adapted species. These species survived glaciations in classical southern refuges with more temperate climates, as well as in western and eastern peripheral Alpine temperate areas. We hypothesized that the European wildcat (Felis silvestris silvestris) populations currently distributed in Italy differentiated in, and expanded from two distinct glacial refuges, located in the southern Apennines and at the periphery of the eastern Alps. This hypothesis was tested by genotyping 235 presumed European wildcats using a panel of 35 domestic cat‐derived microsatellites. To provide support and controls for the analyses, 17 know wildcatxdomestic cat hybrids and 17 Sardinian wildcats (F. s. libyca) were included. Results of Bayesian clustering and landscape genetic analyses showed that European wildcats in Italy are genetically subdivided into three well‐defined clusters corresponding to populations sampled in: (1) the eastern Alps, (2) the peninsular Apennines, and (3) the island of Sicily. Furthermore, the peninsular cluster is split into two subpopulations distributed on the eastern (Apennine mountains and hills) and western (Maremma hills and lowlands) sides of the Apennine ridge. Simulations indicated Alpine, peninsular, and Sicilian wildcats were isolated during the Last Glacial Maximum. Population subdivision in the peninsula cluster of central Italy arose as consequence of a more recent expansions of historically or ecologically distinct European wildcat subpopulations associated with distinct the Continental or Mediterranean habitats. This study identifies previously unknown European wildcat conservation units and supports a deep phylogeographical history for Italian wildcats.
Synthesis and Characterization of Star‐Shaped Donor–Acceptor–Donor Structures
Authors: Pelz Simon , Zhang Jinming , Kanelidis Ioannis , Klink Dennis , Hyzak Lukas , Wulf Volker , Schmitz Oliver J. , Gasse Jan‐Christoph , Frahm Ronald , Pütz Andreas , Colsmann Alexander , Lemmer Uli , Holder Elisabeth
Published: June 2013

A Sonogashira coupling reaction led to star‐shaped 1,3,5‐tris({5‐[7‐(thiophen‐2‐yl)benzo[c][1,2,5]thiadiazol‐4‐yl]thiophen‐2‐yl}ethynyl)benzene derivatives. The star‐shaped molecules were optically analyzed, and – depending on their substitution pattern – they displayed bathochromically shifted absorptions, which were compared to their nonlinked arm precursors. The materials displayed a highly interesting morphology in bulk when blended with [6,6]‐phenyl‐C61‐butyric acid methyl ester (PCBM). One derivative formed columnar structures and revealed prospective use in photodiodes.
Amperometric Detection of Histamine with a Pyrroloquinoline‐Quinone Modified Electrode
Authors: Young Joshua A. , Jiang Xiayu , Kirchhoff Jon R.
Published: June 2013

A modified glassy carbon (GC) electrode was developed for the amperometric detection of biogenic amines, particularly histamine. The electrode was modified with the co‐enzyme pyrroloquinoline quinone (PQQ) by entrapment during electropolymerziation of pyrrole to form polypyrrole (PPy). This method formed a thin film on the electrode surface possessing very good stability with a shelf‐life exceeding one month without loss of signal. Optimal conditions for the PQQ/PPy electrode were determined and a linear response was found for histamine in phosphate buffer (pH 6) at +550 mV from 40 to 170 mg L−1 with a limit of detection (S/N≥3) of 38 mg L−1. The practical linear range offered by this method suggests ideal use for spoilage detection in fermented foods.
Parameters affecting Mg(OH)2 extraction from serpentinites in lithuania for the purpose of CO2 reduction by mineral carbonation
Authors: Stasiulaitiene I. , Vajegaite V. , Martuzevicius D. , Denafas G. , Sliaupa S. , Fagerlund J. , Zevenhoven R.
Published: June 2013

Mineral sequestration has a great potential for abating CO2 emissions, especially at locations where no opportunities for CO2 geological storage exist. This article focuses on the mineral carbonation of magnesium silicates, that is, serpentinites, which offers an attractive option for CO2 emission mitigation in Lithuania. Mineral CO2 carbonation in a staged gas/solid process route is one of the most prospective approaches. The process was conducted in several steps. Firstly, extraction of the magnesium hydroxide from serpentinite via a solid/solid reaction between serpentinite and ammonium sulfate salt at a temperature interval of 500–540°C was carried out. The maximum Mg extraction (53.70 %) was obtained with the mass ratio of reactants of 2 g serpentinite/3 g ammonium sulfate, reaction temperature, and time of 520°C and 20 min, respectively. Secondly, the process of precipitation of Mg(OH)2 took place. The effect of precipitation of the Fe‐containing compounds (first step) and the Mg(OH)2 (second step) was analyzed. At the pH of 8–10 and 10–12, compounds of Fe and Mg precipitated, respectively. The optimal Fe removal and Mg extraction was achieved at the pH of the ∼9.5 for the first step and at the pH of ∼11.50 for the second step. Finally, the carbonation of extracted magnesium hydroxide was accomplished and reached the effectiveness of 65 % after 15 min at 535°C, 51 bar. © 2013 American Institute of Chemical Engineers Environ Prog, 33: 512–518, 2014
Influence of calcination temperature on CeO2‐CuO catalyst for the selective catalytic reduction of NO with NH3
Authors: Pan Wei‐guo , Zhou Yue , Guo Rui‐tang , Zhen Wen‐long , Hong Jie‐nan , Xu Hong‐jian , Jin Qiang , Ding Cheng‐gang , Guo Shi‐yi
Published: June 2013

CeO‐CuO catalysts were prepared by citric acid method at different calcination temperatures. The purpose of this study is to investigate the influence of calcination temperature on the catalytic activity of CeO2‐CuO catalyst for the selective catalytic reduction of NO with NH3. As can be seen from the results, Ce‐Cu(450) is of the best low temperature selective catalytic reduction (SCR) activity among the three catalysts, which may be resulted from its large surface area, good redox ability, strong NH3 adsorption capacity, and high concentration of Cu2+ and active oxygen species on the surface. © 2013 American Institute of Chemical Engineers Environ Prog, 33: 385–389, 2014
Photocatalytic degradation of herbicide isoproturon in TiO2Aqueous Suspensions: Study of Reaction Intermediates and Degradation Pathways
Authors: Verma Anoop , Prakash N. Tejo , Toor Amrit Pal
Published: June 2013

Heterogeneous photocatalytic degradation and mineralization of Isoproturon (IPU) was investigated in aqueous solutions containing titanium dioxide. The degradation was monitored by observing the change in absorption intensity in UV range and through HPLC analysis. The degradation rate was found to be strongly dependent on catalyst concentration, initial pH, and substrate concentration. The effect of variation in intensity of UV irradiations, catalyst recycling as well as area/volume is also studied for the practical applications. The degradation rate was observed to follow first‐order kinetics. TiO2loading 0.5 g L−1, pH 5.0,C0= 25 mg L−1were the optimized conditions for obtaining the better degradation rates. Reduction in COD and TOC values along with the generation of ammonium further indicated the mineralization of the IPU. Fixed bed studies on glass sheet and small cement slabs eliminates the drawbacks of slurry mode photocatalysis. An attempt was also made to identify the intermediates (degradation products) through LC‐MS analysis. © 2013 American Institute of Chemical Engineers Environ Prog, 33: 402–409, 2014
Optimization and kinetics analysis of xanthan gum wastewater treatment with pyrolusite
Authors: Zhao Zhupeng , Zhou Chengxianyi , Zhang Xiaohui , Zhang Yongkui
Published: June 2013

This article deals with treating actual xanthan gum wastewater with pyrolusite by Response Surface Methodology (RSM). The effects of solid‐to‐liquid ratio, sulfuric acid concentration, reaction time, and temperature on COD removal efficiency of xanthan gum wastewater were studied with laboratory bench‐scale experiments. The results showed that the maximum removal rate of COD was 65.63% on the optimum treatment conditions (temperature of 87.3°C, sulfuric acid concentration of 88.15 g/L, solid‐to‐liquid ratio of 9.57%, and time of 3.49 h). Temperature, reaction time, sulfuric acid concentration and solid‐to‐liquid ratio were four important factors which should be well controlled to guarantee high COD removal rate. The activation energy was determined to be 36.08 kJ/mol and the reaction orders with respect to xanthan gum wastewater and H+ concentration was −2.020 and 1.097, respectively. The kinetics analysis showed that the reaction was controlled by both chemical reaction on particle surface and diffusion across the product layer. This study would offer a fundamental method for xanthan gum wastewater treatment with flexibility, simplicity, and high efficiency. © 2013 American Institute of Chemical Engineers Environ Prog, 33: 430–436, 2014
Applying Shape‐Controlled Pt Nano‐dendrites Supported on Carbon for Membrane‐Electrode Assembly in a Proton Exchange Membrane Fuel Cell
Authors: Kim C. , Lee H.
Published: June 2013

Platinum nano‐dendrites of various sizes were applied as cathode catalysts in a proton exchange membrane fuel cell (PEMFC). The membrane electrode assembly (MEA) fabricated with Pt nano‐dendrites showed very high ORR activity at high potential ranges due to lower activation overpotential. But it showed the cell performance only comparable to commercial Pt/C due to Ohmic and mass transfer resistance at high current density ranges. These results demonstrate that both high intrinsic activity of the catalysts and the formation of three‐phase interface with efficient proton, electron, and mass transfer should be considered together when shape‐controlled metal nanoparticles are used as cathode catalysts in a PEMFC.
Multimodel projections and uncertainties of irrigation water demand under climate change
Authors: Wada Yoshihide , Wisser Dominik , Eisner Stephanie , Flörke Martina , Gerten Dieter , Haddeland Ingjerd , Hanasaki Naota , Masaki Yoshimitsu , Portmann Felix T. , Stacke Tobias , Tessler Zachary , Schewe Jacob
Published: June 2013

Crop irrigation is responsible for 70% of humanity's water demand. Since the late 1990s, the expansion of irrigated areas has been tapering off, and this trend is expected to continue in the future. Future irrigation water demand (IWD) is, however, subject to large uncertainties due to anticipated climate change. Here, we use a set of seven global hydrological models (GHMs) to quantify the impact of projected global climate change on IWD on currently irrigated areas by the end of this century, and to assess the resulting uncertainties arising from both the GHMs and climate projections. The resulting ensemble projections generally show an increasing trend in future IWD, but the increase varies substantially depending on the degree of global warming and associated regional precipitation changes. Under the highest greenhouse gas emission scenario (RCP8.5), IWD will considerably increase during the summer in the Northern Hemisphere (>20% by 2100), and the present peak IWD is projected to shift one month or more over regions where ≥80% of the global irrigated areas exist and 4 billion people currently live. Uncertainties arising from GHMs and global climate models (GCMs) are large, with GHM uncertainty dominating throughout the century and with GCM uncertainty substantially increasing from the midcentury, indicating the choice of GHM outweighing by far the uncertainty arising from the choice of GCM and associated emission scenario.
Relationship between reflux and laryngeal cancer
Authors: Coca–Pelaz Andrés , Rodrigo Juan P. , Takes Robert P. , Silver Carl E. , Paccagnella Daniela , Rinaldo Alessandra , Hinni Michael L. , Ferlito Alfio
Published: June 2013

Gastroesophageal reflux disease (GERD), or its variation known as laryngopharyngeal reflux (LPR), has been recognized as a potential cause of several laryngeal disorders. Patients with laryngeal cancer have lifestyle risk factors, especially tobacco and alcohol consumption, that play an etiological role in the development of their cancer but also places them at risk for reflux. The question then arises whether there is merely an association or a causal relationship between laryngeal cancer and reflux. However, despite a number of studies, a causal relationship with laryngeal cancer is uncertain. In this article, we address the current literature in a critical manner to evaluate the relationship between reflux and laryngeal cancer. From the review of the literature, we conclude that there is insufficient evidence to support a causal role of reflux in laryngeal cancer, mainly because of the confounding effect of tobacco and alcohol consumption and the inaccuracies in the diagnosis of reflux. © 2013 Wiley Periodicals, Inc. Head Neck 35: 1814–1818, 2013
Effects of changes in winter snowpacks on summer low flows: case studies in the Sierra Nevada, California, USA
Authors: Godsey S. E. , Kirchner J. W. , Tague C. L.
Published: June 2013

Seasonal low flows are important for sustaining ecosystems and for supplying human needs during the dry season. In California's Sierra Nevada mountains, low flows are primarily sustained by groundwater that is recharged during snowmelt. As the climate warms over the next century, the volume of the annual Sierra Nevada snowpack is expected to decrease by ~40–90%. In eight snow‐dominated catchments in the Sierra Nevada, we analysed records of snow water equivalent (SWE) and unimpaired streamflow records spanning 10–33 years. Linear extrapolations of historical SWE/streamflow relationships suggest that annual minimum flows in some catchments could decrease to zero if peak SWE is reduced to roughly half of its historical average. For every 10% decrease in peak SWE, annual minimum flows decrease 9–22% and occur 3–7 days earlier in the year. In two of the study catchments, Sagehen and Pitman Creeks, seasonal low flows are significantly correlated with the previous year's snowpack as well as the current year's snowpack. We explore how future warming could affect the relationship between winter snowpacks and summer low flows, using a distributed hydrologic model Regional Hydro‐ecologic Ecosystem Simulation System (RHESSys) to simulate the response of two study catchments. Model results suggest that a 10% decrease in peak SWE will lead to a 1–8% decrease in low flows. The modelled streams do not dry up completely, because the effects of reduced SWE are partly offset by increased fall or winter net gains in storage, and by shifts in the timing of peak evapotranspiration. We consider how groundwater storage, snowmelt and evapotranspiration rates, and precipitation phase (snow vs rain) influence catchment response to warming. Copyright © 2013 John Wiley & Sons, Ltd.
Total least square method applied to rating curves
Authors: Kim Byungsoo , Lee Taesam , Ouarda Taha B. M. J.
Published: June 2013

The ordinary least square method (OLS) has been the most frequently used least square method in hydrological data analysis. Its computational algorithm is simple, and the error analysis is also simple and clear. However, the primary assumption of the OLS method, which states that the dependent variable is the only error‐contaminated variable and all other variables are error free, is often violated in hydrological data analyses. Recently, a matrix algorithm using the singular value decomposition for the total least square (TLS) method has been developed and used in data analyses as errors‐in‐variables model where several variables could be contaminated with observational errors. In our study, the algorithm of the TLS is introduced in the evaluation of rating curves between the flow discharge and the water level. Then, the TLS algorithm is applied to real data set for rating curves. The evaluated TLS rating curves are compared with the OLS rating curves, and the result indicates that the TLS rating curve and the OLS rating curve are in good agreement. The TLS and OLS rating curves are discussed about their algorithms and error terms in the study. Copyright © 2013 John Wiley & Sons, Ltd.
Combining two filter paper‐based analytical methods to monitor temporal variations in the geochemical properties of fluvial suspended particulate matter
Authors: Cooper R. J. , Rawlins B. G. , Lézé B. , Krueger T. , Hiscock K. M.
Published: June 2013

Many of the commonly used analytical techniques for assessing the properties of fluvial suspended particulate matter (SPM) are neither cost effective nor time efficient, making them prohibitive to long‐term high‐resolution monitoring. We present an in‐depth methodology utilizing two types of spectroscopy which, when combined with automatic water samplers, can generate accurate, high‐temporal resolution SPM geochemistry data, inexpensively and semi‐destructively, directly from sediment covered filter papers. A combined X‐ray fluorescence spectroscopy and diffuse reflectance infrared Fourier transform spectroscopy approach is developed to estimate concentrations for a range of elements (Al, Ca, Ce, Fe, K, Mg, Mn, Na, P, Si, Ti) and compounds (organic carbon, Aldithionate, Aloxalate, Fedithionate, and Feoxalate) within SPM trapped on quartz fibre filters at masses as low as 3 mg. Calibration models with small prediction errors are derived, along with mass correction factor models to account for variations in retained SPM mass. Spectral pre‐processing methods are shown to enhance the reproducibility of results for some compounds, and the importance of filter paper selection and homogeneous sample preparation in minimizing spectral interference is emphasized. The geochemical signal from sediment covered filter papers is demonstrated to be time stable enabling samples to be stored for several weeks prior to analysis. Example results obtained during a heavy precipitation event in October 2012 demonstrate the methodology presented here has considerable potential to be utilized for high‐resolution monitoring of SPM geochemistry under a range of in‐stream hydrological conditions. Copyright © 2013 John Wiley & Sons, Ltd.
Advances in pan‐European flood hazard mapping
Authors: Alfieri Lorenzo , Salamon Peter , Bianchi Alessandra , Neal Jeffrey , Bates Paul , Feyen Luc
Published: June 2013

Flood hazard maps at trans‐national scale have potential for a large number of applications ranging from climate change studies, reinsurance products, aid to emergency operations for major flood crisis, among others. However, at continental scales, only few products are available, due to the difficulty of retrieving large consistent data sets. Moreover, these are produced at relatively coarse grid resolution, which limits their applications to qualitative assessments. At finer resolution, maps are often limited to country boundaries, due to limited data sharing at trans‐national level. The creation of a European flood hazard map would currently imply a collection of scattered regional maps, often lacking mutual consistency due to the variety of adopted approaches and quality of the underlying input data.

In this work, we derive a pan‐European flood hazard map at 100 m resolution. The proposed approach is based on expanding a literature cascade model through a physically based approach. A combination of distributed hydrological and hydraulic models was set up for the European domain. Then, an observed meteorological data set is used to derive a long‐term streamflow simulation and subsequently coherent design flood hydrographs for a return period of 100 years along the pan‐European river network. Flood hydrographs are used to simulate areas at risk of flooding and output maps are merged into a pan‐European flood hazard map. The quality of this map is evaluated for selected areas in Germany and United Kingdom against national/regional hazard maps. Despite inherent limitations and model resolution issues, simulated maps are in good agreement with reference maps (hit rate between 59% and 78%, critical success index between 43% and 65%), suggesting strong potential for a number of applications at the European scale. Copyright © 2013 John Wiley & Sons, Ltd.
Linear response functions of two convective parameterization schemes
Authors: Herman Michael J. , Kuang Zhiming
Published: June 2013

Two 1‐D atmospheric column models containing convective parameterization schemes are compared to a 3‐D cloud system resolving model (CSRM) using a recent technique that admits study of responses of convection to small temperature and moisture anomalies. The MIT Single‐Column Model (MSCM) and Diabat3 (D3) are the column models of study. There exist notable differences between the responses of the column models and those of the CSRM. Both column models retain prescribed temperature anomalies and MSCM retains moisture anomalies for much longer than the CSRM. D3 excessively warms anomalous moist layers. Neither column model warms the upper troposphere following moist anomalies or cools the upper troposphere following warm anomalies in the middle troposphere. Responses in both column models are mostly local—suggesting that a significant attribute of the CSRM response is missing from these models. Such differences have implications to the simulation of large‐scale convective phenomena, such as the growth and propagation of convectively coupled waves (CCW). The technique employed herein can be used as a basis for tuning and modifying convective parameterization schemes.
A Raman spectroscopy bio‐sensor for tissue discrimination in surgical robotics
Authors: Ashok Praveen C. , Giardini Mario E. , Dholakia Kishan , Sibbett Wilson
Published: June 2013

We report the development of a fiber‐based Raman sensor to be used in tumour margin identification during endoluminal robotic surgery. Although this is a generic platform, the sensor we describe was adapted for the ARAKNES (Array of Robots Augmenting the KiNematics of Endoluminal Surgery) robotic platform. On such a platform, the Raman sensor is intended to identify ambiguous tissue margins during robot‐assisted surgeries. To maintain sterility of the probe during surgical intervention, a disposable sleeve was specially designed. A straightforward user‐compatible interface was implemented where a supervised multivariate classification algorithm was used to classify different tissue types based on specific Raman fingerprints so that it could be used without prior knowledge of spectroscopic data analysis. The protocol avoids inter‐patient variability in data and the sensor system is not restricted for use in the classification of a particular tissue type. Representative tissue classification assessments were performed using this system on excised tissue. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
QSARINS: A new software for the development, analysis, and validation of QSAR MLR models
Authors: Gramatica Paola , Chirico Nicola , Papa Ester , Cassani Stefano , Kovarich Simona
Published: June 2013

QSARINS (QSAR‐INSUBRIA) is a new software for the development and validation of multiple linear regression Quantitative Structure‐Activity Relationship (QSAR) models by Ordinary Least Squares method and Genetic Algorithm for variable selection. This program is mainly focused on the external validation of QSAR models. Various tools for explorative analysis of the datasets by Principal Component Analysis, prereduction of input molecular descriptors, splitting of datasets in training and prediction sets, detection of outliers and interpolated or extrapolated predictions, internal and external validation by different parameters, consensus modeling and various plots for visualizations are implemented. QSARINS is a user‐friendly platform for QSAR modeling in agreement with the OECD Principles and for the analysis of the reliability of the obtained predicted data. The Insubria Persistent Bioaccumulative and Toxic (PBT) Index model for the prediction of the cumulative behavior of new chemicals as PBTs is implemented. Additionally, QSARINS allows the user to validate single models, predeveloped using also different software. © 2013 Wiley Periodicals, Inc.
Vertical and meridional equatorial ion flows observed by CINDI during the 26 September 2011 storm
Authors: Hairston Marc R. , Coley W. Robin , Stoneback Russell
Published: June 2013

The equatorial ionosphere is generally shielded from outside electrical fields except during large geomagnetic storms. During these storms, the polar region electric fields can temporarily extend to the equatorial regions in what is called a penetration field. During the subsequent recovery period, a disturbance dynamo is produced with an enhanced electric field with the opposite orientation relative to the penetration field. The penetration electric field would be oriented toward the east on the dayside causing an excess upward E × B motion of the equatorial ionospheric ions. The disturbance dynamo electric field would have the opposite orientation, westward on the dayside, producing an excess downward E × B motion of the equatorial ionospheric ions. The moderate storm (minimum Dst = −103 nT) on 26 September 2011 is examined using ion flow data from the Coupled Ion‐Neutral Dynamics Investigation (CINDI) thermal plasma instrument package on the Communication/Navigation Outage Forecast System (C/NOFS) spacecraft on the dayside and early evening local times to look for examples of these flows. Despite what should have been a large enough storm to produce penetration fields and upward flows, a detailed examination of the observed flows from this storm shows only enhanced downward flows before the storm, during the main phase, and through the recovery.
Global TEC maps based on GNNS data: 2. Model evaluation
Authors: Mukhtarov P. , Pancheva D. , Andonov B. , Pashova L.
Published: June 2013

The present paper presents a detailed statistical evaluation of the global empirical background TEC model built by using the CODE TEC data for full 13 years, 1999‐2011, and described in Part 1. It has been found that the empirical probability density distribution resembles more the Laplace than the Gaussian distribution. A further insight into the nature and sources of the model's error variable led up to building of a new error model. It has been constructed by using a similar approach to that of the background TEC model. The spatial‐temporal variability of the RMSE (root mean squares error) is presented as a multiplication of three separable functions which describe solar cycle, seasonal and LT dependences. The error model contains 486 constants that have been determined by least squares fitting techniques. The overall standard deviation of the predicted RMSE with respect to the empirical one is 0.7 TECU. The error model could offer a prediction approach on the basis of which the RMSE depending on the solar activity, season and LT is predicted.
Global TEC maps based on GNSS data: 1. Empirical background TEC model
Authors: Mukhtarov P. , Pancheva D. , Andonov B. , Pashova L.
Published: June 2013

A global background total electron content (TEC) model is built by using the Center for Orbit Determination of Europe (CODE) TEC data for full 13 years, 1999–2011. It describes the climatological behavior of the ionosphere under both its primary external driver, i.e., the direct photo‐ionization by incident solar radiation, and regular wave particularly tidal forcing from the lower atmosphere. The model construction is based on the very different time scales of the solar cycle, seasonal, and diurnal TEC variabilities (at least an order of magnitude); this leads to modulations of shorter‐period variabilities with periods of the longer ones. Then the TEC spatial‐temporal variability is presented as a multiplication of three separable functions. The solar activity is described by both parameters: F10.7 and its linear rate of change KF while the seasonal variability is presented by sine functions including four subharmonics of the year. The diurnal variability of the TEC model is described by 2D (longitude‐time) sine functions with zonal wave numbers up to 4 and 4 subharmonics of the solar day. The model offers TEC maps which depend on geographic coordinates (5°×5° in latitude and longitude) and UT at given solar activity and day of the year. The presented background model fits to the CODE TEC input data with a zero systematic error and an RMS error of 3.387 TECU. It is able to reproduce the well‐known ionospheric structures as Weddell Sea Anomaly and some longitudinal wave‐like structures.