bluuebunny/crossref_metadata_2025 huggingface dataset:
Flow and sediment regimes at tributary junctions on a regulated river: impact on sediment residence time and benthic macroinvertebrate communities
Authors: Svendsen Kristen M. , Renshaw Carl E. , Magilligan Francis J. , Nislow Keith H. , Kaste James M.
Published: October 2008

Tributaries may either ameliorate or exacerbate the geomorphic and ecologic impacts of flow regulation by altering the flux of water and sediment into the flow‐regulated mainstem. To capture the effects of tributary influences on a flow regulated river, long‐term discharge and cross‐sectional data are used to assess the geomorphic and hydrologic impacts of impoundment. In addition, the use of the short‐lived cosmogenic radioisotope 7Be (half‐life 53·4 days) to link sediment transport dynamics to benthic macroinvertebrate community structure is evaluated. It is found that the 7Be activity of transitional bed load sediment is highly seasonal and reflects both variations in activity of sediment sources and limited sediment residence time within the junction. Benthic communities also exhibit a strong seasonal variability. In the spring, neither the 7Be activity of the sediment, nor benthic communities exhibit clear relationships with sample site location. In contrast, during the late summer the ratio of Ephemeroptera (mayflies)/Trichoptera (caddisflies) decreased significantly below tributary junctions. This decrease in benthic community ratio was driven by increases in caddisfly abundance and was strongly correlated with the presence of recently 7Be tagged transitional bedload sediment. These observations are probably associated with the presence of coarse, stable, and unembedded substrate downstream of tributaries and the rapid turnover of sediment that may also be associated with a rapid flux in nutrients or seston. The results show that tributaries are impacting the flow‐regulated mainstem and that these impacts are reflected in the benthic community structure and in the 7Be activity of transitional bed load sediment. Moreover, the observed reduction in competence and capacity of the mainstem following flood control suggests that these spatial discontinuities may be a consequence of impoundment. Copyright © 2008 John Wiley & Sons, Ltd.
Monitoring drought severity in agriculture through a synthetic index based on dry periods: a case study in the Mediterranean basin
Authors: Salvati Luca , Venezian‐Scarascia Maria‐Elisa , Zitti Marco
Published: October 2008

Drought is usually defined as a significant, temporary reduction in water availability below the expected amount for a specified period and for a defined climatic zone. Drought episodes may be described by means of different characteristics, namely drought duration and intensity, considered as the two dimensions of this agro‐climatic phenomenon. Among the several methods proposed for describing drought, the run method appears as suitable to provide an objective characterisation of drought events. A simple drought index, obtained from only two input variables (rainfall and reference evapotranspiration), able to describe different dimensions of drought phenomena (duration, intensity and severity), and to recognise “normal” conditions, both in statistical and ecological terms, is meaningful. Our interest is therefore to develop such a drought index, able to produce information on a detailed geographic and time scale.

The procedure we have built up consists in calculating for each day, considered as dry or wet, the length of the present dry spell (LH) and water deficit (DF). The same variables were computed over a six‐month period preceding the evaluation day (LH6 and DF6). For each day to be evaluated we associated each agro‐climatological variable with the corresponding percentile value obtained from the climatology data set. Two partial indicators depicting drought duration (LHS) and intensity (DFS) were introduced. LHS and DFS were computed respectively as the maximum daily value between LH and LH6, and between DF and DF6. A synthetic index of drought severity (DSI) was finally obtained as the geometric mean of LHS and DHS indicators.

Using dry spell climatology we estimated duration, intensity and severity of drought on a daily basis over the test period 1988–2003. The most arid period in Italy was recorded during spring–summer 2003, when especially dry conditions occurred in northern and central Italy. DSI correctly indicates a significant increase of drought from March to July 2003 throughout Italy: drought severity reaches the 90 percentile in all the stations from Po plain, Apennines, and coastal areas of central Italy.

In conclusion, DSI may be used to assess the agro‐climatic conditions occurring in a certain location through only two input variables. It allows a synthetic description of drought episodes in terms of both dry spell length and water balance. Copyright © 2008 John Wiley & Sons, Ltd.
Correlation of histology and linear and nonlinear microscopy of the living human cornea
Authors: Masters Barry R.
Published: October 2008

The morphology and the function of cellular and non‐cellular structures in the living human cornea can be determined with modern correlative linear and nonlinear optical microscopic techniques and histology. Correlative microscopy is based on the use of different optical techniques to study the same specimen, ideally at the same location within the specimen, in order to increase the functional and/or morphological understanding of the specimen. A case study to assess the effect of overnight lid‐closure on in vivo human corneal morphology is presented to illustrate correlative linear microscopy and optical low‐coherence reflectometry. Nonlinear multiphoton excitation microscopy provides functional information on cellular metabolism based on the intrinsic fluorescence from the reduced pyridine nucleotides and the oxidized flavoproteins. Second‐harmonic generation microscopy, a scattering process that does not deposit net energy into the tissue, provides structural information on corneal collagen organization. Molecular third‐harmonic generation microscopy generates a signal in all materials and it an emerging technique. Coherent anti‐Stokes Raman scattering microscopy provides chemical imaging for biology and medicine. The comparison and limitations of these microscopic modalities, linear and nonlinear microscopy applied to the cornea, and a review of some key findings is analyzed. A correlative integration and correlation of linear and nonlinear microscopies to study corneal function and structure is proposed to validate the clinical interpretation of microscopic images of the cornea. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A theoretical study on fullerene‐dizincocene hybrids
Authors: Gao Guohua , Xu Xiang , Kang Hong Seok
Published: October 2008

Using the density functional theory, we investigated the possible formation of fullerene‐dizincocene hybrids, specifically C60*‐Zn‐Zn‐Cp*, C60*‐Zn‐Zn‐C60*, C70*‐Zn‐Zn‐Cp*, and C70*‐Zn‐Zn‐C70*, where C60*, Cp*, and C70* represent C60(CH3)5, C5(CH3)5, and C70(CH3)5 radicals. Our calculation shows that these hybrids have HOMO‐LUMO gaps which are larger than has been experimentally identified for C60*‐Fe‐Cp. In addition, the strength of the ZnZn bonds is similar to that in Cp*‐Zn‐Zn‐Cp* which was also synthesized recently. Furthermore, heterohybrids, C60*‐Zn‐Zn‐Cp* and C70*‐Zn‐Zn‐Cp* are expected to exist in equilibria with homohybrids, C60*‐Zn‐Zn‐C60* and C70*‐Zn‐Zn‐C70*, in which heterohybrids are much more favored. On the other hand, another hybrid involving Sc3N@C68 as a fullerene unit is not highly probable. © 2008 Wiley Periodicals, Inc. J Comput Chem, 2009
Decolorisation of synthetic dyes by crude laccase from Rigidoporus lignosus W1
Authors: Li Li , Dai Wenkui , Yu Peng , Zhao Jian , Qu Yinbo
Published: October 2008

BACKGROUND: Effluents from the dyeing process containing dyes are difficult to degrade biologically. Therefore enzymatic dye decolorisation has received considerable attention recently. In this study the dye decolorisation potential of crude laccase from the white rot fungus Rigidoporus lignosus W1 was demonstrated on an anthraquinone dye, Remazol Brilliant Blue R (RBBR), and a triphenylmethane dye, malachite green (MG). Effects of pH, temperature and ionic strength on laccase activity and decolorisation efficiency were investigated.

RESULTS: Native polyacrylamide gel electrophoresis (PAGE) and sodium dodecyl sulfate PAGE confirmed the decolorisation ability of the crude enzyme on RBBR and MG. A single laccase with a molecular mass of about 40 kDa appeared to be involved in the process. Efficient enzymatic decolorisation without redox mediator was achieved, with 39 mg L−1 MG being removed within 2 h and 160 mg L−1 RBBR within 1 h at 60 °C and pH 4.5. Although the laccase activity was inhibited in the presence of NaCl, it was renatured gradually in low concentrations of NaCl (<0.8 mol L−1), resulting in unusual dye decolorisation kinetics. Surprisingly, unusual storage stability at alkaline pH was observed, with the laccase activity being enhanced 1.5–2‐fold after 3 h of incubation.

CONCLUSION: Crude laccase with unusual storage stability from the fungus R. lignosus W1 showed excellent decolorisation ability on RBBR and MG without redox mediator. This laccase would seem to be a good candidate for application in dye decolorisation and textile effluent biotreatment. Copyright © 2008 Society of Chemical Industry
Purification and biochemical characterization of an intracellular lipase by Rhizopus chinensis under solid‐state fermentation and its potential application in the production of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)
Authors: Sun Shu Yang , Xu Yan , Wang Dong
Published: October 2008

BACKGROUND: Purification and characterization of an intracellular lipase produced by Rhizopus chinenesis cultured in solid‐state fermentation was investigated. The potential application in concentrating eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) from fish oil by the pure enzyme was also studied.

RESULTS: Through four successive purification steps, the enzyme was purified to homogeneity with an apparent molecular mass of 36 kDa. The lipase was active for pH between 7.0 and 9.0 and temperatures 20–45 °C. Lipase activity was slightly increased in the presence of Ca2+ and Mg2+, but strongly inhibited by Hg2+ and SDS. The pure enzyme was most active on medium chain p‐nitrophenol esters, with the highest activity towards pNP‐caprylate (C8). The enzyme is a non‐specific lipase, because it cleaved not only the 1,3‐positioned ester bonds but also the 2‐positioned bond in triolein. High EPA (17.6%) and DHA (32.9%) contents were achieved using the pure lipase (100 U) within 10 h.

CONCLUSION: The enzymatic activity of the lipase on a wide variety of substrates and its stability in the presence of some organic solvents suggest that the lipase should be investigated for a range of commercial applications. The pure lipase was proved to possess potential ability for the production and concentration of EPA and DHA from fish oil. Copyright © 2008 Society of Chemical Industry
Removal of H2S using a new Ce(IV) redox mediator by a mediated electrochemical oxidation process
Authors: Chandrasekara Pillai K. , Raju T. , Chung Sang Joon , Moon Il‐Shik
Published: October 2008

BACKGROUND:Hydrogen sulfide (H2S) from industrial activities and anaerobic manure decomposition in commercial livestock animal operations is an offensive malodorous and toxic gas even in small concentrations, causing serious discomfort and health and social problems. The objective of this study was to employ for the first time a novel, attractive, low cost, environmentally benign mediated electrochemical oxidation (MEO) process with Ce(IV) as the redox catalyst for H2S gas removal from an H2S–air feed mixture.

RESULTS:The influence of liquid flow rate (QL) from 2–4 L min−1, gas flow rate (QG) from 30–70 L min−1, H2S concentration in the H2S–air feed mixture from 5–15 ppm, and Ce(III) pre‐mediator concentration in the electrochemical cell from 0.1–1 mol L−1on H2S removal efficiency were investigated. Both liquid and gas flow rates influenced the removal efficiencies, but in opposite directions. Nearly 98% H2S removal was achieved when the concentration of Ce(IV) mediator ion in the flowing scrubbing liquid reached 0.08 mol L−1.

CONCLUSIONS:The new MEO method proved promising for H2S removal, achieving high removal efficiency. Integration of the electrochemical cell with the scrubber set‐up ensured continuous regeneration of the mediator and its repeated reuse for H2S removal, avoiding use of additional chemicals. Since the process works at room temperature and atmospheric pressure utilizing conventional transition metal oxide electrodes more commonly used in industrial applications, it is also safe and economical. Copyright © 2008 Society of Chemical Industry
The preparation of three new partially deuterated hexadecanethiols for applications in surface chemistry
Authors: Sheepwash Erin E. , Rowntree Paul A. , Schwan Adrian L.
Published: October 2008

The synthesis of three partially deuterated hexadecanethiols has been achieved. Thiols CH3(CH2)7(CD2)8SH, CD3(CD2)7(CH2)8SH and CD3(CH2)15SH were targeted, as these compounds, after formation of self‐assembled monolayers on Au(1 1 1) or Au nanoparticles, can provide mechanistic information pertaining to reactive atom migrations within the assembly. The syntheses of each of these compounds called upon Grignard coupling chemistry, which was activated by Li2CuCl4. Applicable deuterium containing fragments were either commercially obtained or constructed from by way of an inexpensive and efficient ring opening, protection and dimerization of THF‐d8. Sulfur incorporation was by thiolacetate substitution or addition reactions. The protocols presented possess general applicability in a number of syntheses requiring block‐deuterated fattyalkyl sections. Copyright © 2008 John Wiley & Sons, Ltd.
Synthesis of a 14C‐labeled FPTase inhibitor via a Pd‐catalyzed cyanation with Zn(14CN)2 and via bromo[14C]acetic acid
Authors: Ho Jonathan Z. , Elmore Charles S. , Braun Matthew P.
Published: October 2008

14C‐Labeled farnesyl‐protein transferase inhibitor 1a was required for drug metabolism studies. The first approach was to synthesize 14C‐labeled 1b using Zn(14CN)2 in a Pd‐catalyzed cyanation. A second approach was to prepare labeled 1c with the 14C‐label in the piperazine ring. All metabolites from 1b were non‐radioactive whereas the same metabolites from 1c were all radioactive and quantifiable. Copyright © 2008 John Wiley & Sons, Ltd.
Isolation and characterisation of invertase inhibitor from sweet potato storage roots
Authors: Huang Guan‐Jhong , Sheu Ming‐Jyh , Chang Yuan‐Shiun , Lu Te‐Ling , Chang Heng‐Yuan , Huang Shyh‐Shyun , Lin Yaw‐Huei
Published: October 2008

BACKGROUND: Plant invertases play important roles in sucrose metabolism. Cell wall invertase has been reported to participate in phloem loading and unloading. Soluble invertases are involved in hexose level regulation in mature tissues and in utilisation of stored sucrose within vacuoles. Invertase inhibitory proteins have been described as one of the possible components for invertase activity regulation in some plant species.

RESULTS: In this work an invertase inhibitor (ITI) coding sequence was cloned by differential display from sweet potato (SP) storage roots. SPITI codes for a protein of 192 amino acids with a predicted molecular mass of 20 624 Da containing a 20‐amino‐acid signal peptide and four cysteines. Computer analysis of the deduced amino acid sequences of the conserved domain revealed that the protein belonged to the plant invertase/pectin methylesterase inhibitor. Both the corresponding mRNA and protein levels were found to be highest in storage roots, followed by veins. Recombinant SPITI protein from the storage root cDNA clone overproduced in Escherichia coli (M15) was purified by affinity chromatography. This protein effectively inhibited the invertase activity in a dose‐dependent manner. The results presented in the Lineweaver‐Burk plots indicated that the invertase inhibitor displayed a mode of competitive inhibition towards the invertase tested, with a Ki of 3.82 × 10−6 mol L−1.

CONCLUSION: These results suggested that SPITI is a novel member of the ITI family in plants. SPITI genes of sweet potato storage roots display differential gene expression patterns, which may be associated with sucrose metabolism to cope with particular developmental requirements. Copyright © 2008 Society of Chemical Industry
Effects of subchronic exposure to transgenic papayas (Carica papaya L.) on liver and kidney enzymes and lipid parameters in rats
Authors: Powell Melissa , Wheatley Andrew , Omoruyi Felix , Asemota Helen , Williams Nadia P , Tennant Paula F
Published: October 2008

BACKGROUND: Declines due to Papaya ringspot virus (PRSV) are the primary constraint limiting production of papaya (Carica papaya L.) in tropical and subtropical regions. Given the lack of suitable sources of resistance in the genus, transgenic papayas carrying the coat protein gene of a local strain of PRSV were recently developed to manage the disease in Jamaica. For assurance of food safety, a 90 day subchronic whole‐food feeding study in rats was conducted with transgenic and non‐transgenic papayas.

RESULTS: Male and female Wistar rats (N = 56) received diets containing transgenic or non‐transgenic papayas at twice the equivalent of the average daily human consumption of fresh papayas. No adverse effects on animal behaviour or differences in body weight and organ weight between the animal groups (P < 0.05) were observed during the study. Necropsy at the end of the study indicated that neither pathological nor histopathological abnormalities were present in the liver and kidneys of rats in the control and treated groups. In addition, the levels of activity of plasma, liver and kidney acid and alkaline phosphatases and alanine and aspartate transaminases were comparable (P < 0.05). Although significant differences (P < 0.05) were found in the cholesterol and triglyceride levels in the plasma and liver among animals of the treated groups, overall the values were comparable to those of the control.

CONCLUSION: The results suggest that consumption of transgenic papayas may not have adverse effects in rats as regards the parameters considered in this study. Copyright © 2008 Society of Chemical Industry
Isolation and characterisation of trypsin from sardinelle (Sardinella aurita) viscera
Authors: Ben Khaled Hayet , Bougatef Ali , Balti Rafik , Triki‐Ellouz Yosra , Souissi Nabil , Nasri Moncef
Published: October 2008

BACKGROUND: In Tunisia, sardinelle (Sardinella aurita) catches totalled about 13 300 t in 2002. During processing, solid wastes including heads and viscera are generated, representing about 30% of the original raw material. Viscera, one of the most important by‐products of the fishing industry, are recognised as a potential source of digestive enzymes, especially proteases with high activity over a wide range of pH and temperature conditions. This paper describes the purification procedure and some biochemical characterisation of trypsin from S. aurita viscera.

RESULTS: Trypsin from the viscera of sardinelle (S. aurita) was purified by fractionation with ammonium sulphate, Sephadex G‐75 gel filtration, Sepharose mono Q anion exchange chromatography, ultrafiltration and a second Sephadex G‐75 gel filtration, resulting in a 5.42‐fold increase in specific activity and 6.1% recovery. The molecular weight of the purified enzyme was estimated to be 24 kDa using size exclusion chromatography and sodium dodecyl sulfate polyacrylamide gel electrophoresis. The purified enzyme showed esterase‐specific activity on N‐α‐benzoyl‐L‐arginine ethyl ester (BAEE) that was four times greater than its amidase‐specific activity on N‐α‐benzoyl‐DL‐arginine‐p‐nitroanilide (BAPNA). The optimal pH and temperature for enzyme activity were pH 8 and 55 °C respectively using BAEE as a substrate. The trypsin kinetic constants Km and kcat on BAPNA were 1.67 mmol L−1 and 3.87 s−1 respectively, while the catalytic efficiency kcat/Km was 2.31 s−1 L mmol−1.

CONCLUSION: Trypsin was purified from sardinelle (S. aurita) viscera. Biochemical characterisation of S. aurita trypsin showed that this enzyme can be used as a possible biotechnological tool in the fish‐processing and food industries. Copyright © 2008 Society of Chemical Industry
Fermentation of soybean by Rhizopus promotes the calcium absorption ratio in rats
Authors: Watanabe Nakamichi , Aoki Hideyuki , Fujimoto Kenshiro
Published: October 2008

BACKGROUND: Soy foods are generally considered to be an unfavourable source of calcium because soybean is rich in phytate, which retards the absorption of calcium. The objective of this study was to assess the effect of dietary fermented soybean, such as tempeh, on calcium absorption in rats. The rats were grouped into three dietary groups and fed the experimental diets for 4 weeks. Soybean, conventional tempeh prepared by aerobic fermentation with Rhizopus (tempeh), and novel tempeh prepared by aerobic and successive anaerobic fermentations (anaerobic tempeh) were used as the protein sources of the experimental diets.

RESULTS: The order of the calcium absorption ratio for the 3 days before the end of the test period was as follows: tempeh group > anaerobic tempeh group > soybean group.

CONCLUSION: The calcium absorption ratio of the tempeh group in particular was significantly higher than those of the other two groups. The high calcium absorption ratio of the tempeh group might be caused by both low phytate contents and peptides that are produced during the fermentation of soybean by Rhizopus. Copyright © 2008 Society of Chemical Industry
Effect of chitosan coating in preventing deterioration and preserving the quality of fresh‐cut papaya ‘Maradol’
Authors: González‐Aguilar Gustavo A , Valenzuela‐Soto Elisa , Lizardi‐Mendoza Jaime , Goycoolea Francisco , Martínez‐Téllez Miguel A , Villegas‐Ochoa Mónica A , Monroy‐García Imelda N , Ayala‐Zavala J Fernando
Published: October 2008

BACKGROUND: Chitosan can form antimicrobial, semi‐permeable barriers that limit gas exchange and reduces water loss in fruits. Consumer interest in fresh‐cut papaya fruit is leading to increasing demand because of its sensorial and antioxidant properties. However, papaya is a highly perishable product that is prone to loss of weight, loss of firmness and microbial attack. The aim of this study was to evaluate the effect of chitosan coatings on the overall quality of fresh‐cut papaya. Chitosan coatings of low (LMWC), medium (MMWC) and high (HMWC) molecular weights, at concentrations of 0.01 and 0.02 g mL−1, were applied to fresh‐cut papaya cubes. The treated cubes were stored at 5 °C and changes in quality were evaluated.

RESULTS: MMWC maintained the highest color values (L* and b*) and firmness. Chitosan coatings suppressed mesophilic plate count, and the growth of molds and yeast, compared to controls. The MMWC coatings at 0.02 g mL−1 resulted in the highest antimicrobial activity and decreased the activity of the enzymes polygalacturonase and pectin methylesterase, followed by low and high MW chitosan coatings at 0.02 g mL−1.

CONCLUSION: The application of the MMWC treatment at 0.02 g mL−1 could be used to reduce deteriorative processes, maintain quality and increase the shelf life of fresh‐cut papaya stored at 5 °C. Copyright © 2008 Society of Chemical Industry
Soil and vegetable compositional relationships of eight potentially toxic metals in urban garden fields from northern Nigeria
Authors: Agbenin John O. , Danko M , Welp Gerphard
Published: October 2008

BACKGROUND: Human exposure to heavy metals is attributed to consumption of vegetables raised in polluted soil environment. We examined the concentrations of As, Cd, Co, Cr, Cu, Ni, Pb and Zn in soils and lettuce (Latuca sativa) and amaranthus (Amaranthus caudatus) in 15 garden fields under long‐term wastewater irrigation.

RESULTS: The concentrations of As (0.3–2.1 mg kg−1), Cd (0.07–0.3 mg kg−1), Co (4.6–9.1 mg kg−1) and Cr (21.6–36.2 mg kg−1) in the gardens were consistent with background concentrations in soils, but Ni (12.6–25.7 mg kg−1), Cu (12.5–24.6 mg kg−1), Pb (25.7–71.6 mg kg−1) and Zn (52.3–158 mg kg−1) concentrations were double the concentrations normally encountered in arable fields in the region. The concentrations of Cd and As in the vegetables were within safe limits, but Co (0.14–0.67 mg kg−1 fresh weight (fw)) and Ni (1.0–2.7 mg kg−1 fw) concentrations in lettuce were relatively high for leaf vegetables. The concentration of Pb (0.65–4.80 mg kg−1 fw) was above safe limit of 0.3 mg kg−1 fw, while the concentrations of Cu (1.3–2.7 mg kg−1 fw and Zn (10.2–23.6 mg kg−1 fw) were close to the unsafe limits for leaf vegetables. There were no strong linear correlations between soil metal concentrations and bio‐concentrations in the vegetable crops.

CONCLUSION: We surmise that leaf vegetables can accumulate metals in their tissues to unsafe levels even when total metal concentrations in these soils are below the allowable concentrations in agricultural soils. Copyright © 2008 Society of Chemical Industry
Efficient protocol for purification of diosgenin and two fatty acids from Rhizoma dioscoreae by SFE coupled with high‐speed counter‐current chromatography and evaporative light scattering detection
Authors: Xu Youwei , Han Xu , Dong Deshi , Xu Lina , Qi Yan , Peng Jinyong , Zhan Libin
Published: October 2008

Supercritical fluid extraction (SFE) was used to extract diosgenin, linoleic acid, and linolenic acid following acid hydrolysis from Rhizoma dioscoreae, a famous traditional Chinese medicine. The process was performed using a preparative SFE system under 35 MPa of pressure, 65°C of temperature, and modified CO2 with 95% ethanol for 180 min dynamic extraction. Then, the crude extract was successfully isolated and separated by high‐speed counter‐current chromatography (HSCCC) with evaporative light scattering detection (ELSD). A two‐phase solvent system composed of n‐hexane/ethyl acetate/methanol/water was used for HSCCC separation in a stepwise elution mode. The upper phase of the solvent system at the volume ratio of 1:1:1.4:0.6 by volume was used as the stationary phase, and the mobile phase after 200 min was changed into the lower phase of the solvent system at the volume ratio of 1:1.2:1.4:0.6 by volume. The separation produced a total of 20.8 mg diosgenin, 12.1 mg linoleic acid, and 18.4 mg linolenic acid from 300 mg crude extract in one‐step purification. The purities of the products were 98.9, 99.0, and 99.4%, respectively, as determined by HPLC. Their chemical structures were identified by MS, UV, and the standards.
Managerial incentives for process innovation
Authors: Overvest Bastiaan M. , Veldman Jasper
Published: October 2008

Cost‐reducing investments by firms are often not publicly observable. This lack of observability would preclude a strategic use of process innovation. However, we show that an observable and verifiable contract that provides direct monetary incentives for cost reductions — an innovation incentive contract — can act as a strategic commitment device. Our model predicts that manager‐led firms are more innovative than owner‐led firms and that these contracts become less prevalent as product market competition intensifies. Both predictions are consistent with recent empirical evidence. Copyright © 2008 John Wiley & Sons, Ltd.
Social norms, coordination and collaboration in heterogeneous teams
Authors: Antonetti Marilyne , Rufini Alexandra
Published: October 2008

This paper considers the coordinating role of social norms in a heterogeneous team of workers. We define an optimal unit of production as a form of organisation involving several teams and members, with the following properties: (i) a social norm operating to coordinate individual efforts; (ii) a team with heterogeneous skills, enabling generation of synergies. Our model suggests that competences of the best worker are transferred to his or her peers. This collaborative process enhances team efficiency but only if there is an implicit ex ante coordinating device based on social norms that discourage free riding. Copyright © 2008 John Wiley & Sons, Ltd.
Indicators and indexes of directional output loss and input allocative inefficiency
Authors: Fukuyama Hirofumi , Weber William L.
Published: October 2008

We extend Grosskopf et al.'s method and create an output loss indicator using directional output distance functions that allows non‐radial efficiency gains in output. We compare our new output loss indicator with an indicator of input allocative inefficiency and derive the necessary and sufficient condition for equivalence between the two indicators. We also present an output loss index and corresponding input allocative inefficiency index and consider how indexes are related. Then we extend our analysis to productivity change and derive the necessary and sufficient condition for an output loss change indicator to be equivalent to an indicator of input allocative inefficiency change. Copyright © 2008 John Wiley & Sons, Ltd.
Pricing by state‐owned enterprises: the case of postal services
Authors: Geddes R. Richard
Published: October 2008

Sappington and Sidak develop a model of state‐owned enterprise (SOE) pricing behavior in which firms maximize a weighted average of revenues and profits. The model predicts that SOEs will lower prices in more‐elastic markets and raise them in less‐elastic markets if the weight they place on profit is positive. The Postal Reorganization Act of 1970 relaxed the institutional constraints on pricing by the US Postal Service, which allows a test of the Sappington–Sidak model. The model's predictions are broadly confirmed. Congress passed the Postal Accountability and Enhancement Act in 2006, which may help address some anticompetitive concerns in this industry. Copyright © 2008 John Wiley & Sons, Ltd.
The impact of managerial quality on organizational performance: evidence from German soccer
Authors: Frick Bernd , Simmons Robert
Published: October 2008

In this paper we use a novel panel data set from the German premier soccer league (Bundesliga) as a case to show how variations in managerial compensation impact positively upon organizational (team) success. Using stochastic frontier analysis, we find that a team that hires a better quality coach can expect to achieve a higher league points total by reducing technical inefficiency. However, our results also suggest that the market for head coaches may be allocatively inefficient in that coaches are paid below their marginal revenue products. Copyright © 2008 John Wiley & Sons, Ltd.
Behavioral approaches to optimal FDI incentives
Authors: Rosenboim M. , Luski I. , Shavit T.
Published: October 2008

Countries attempt to attract foreign investors by offering them a set of incentives. The most common types of foreign direct investment incentives are grants and tax relief. Although the amount of the grant is independent of future situations, the value of a tax relief depends on future profits. Our study used the behavioral approach to test experimentally the preferences of managers regarding the desired types of incentives under various conditions. We found, ‘Regret Effect’, ‘Statues Quo Bias’, and ‘Insurance Effect’ in subjects' decision making. A country can improve the incentives it offers by considering the various behavioral biases of the companies' managers. Copyright © 2008 John Wiley & Sons, Ltd.
Quality of life in early Parkinson's disease treated with levodopa/carbidopa/entacapone
Authors: Fung Victor S.C. , Herawati Lilie , Wan Ying ,   Movement Disorder Society of Australia Clinical Research and Trials Group,   on behalf of the QUEST‐AP Study Group
Published: October 2008

We aimed to investigate whether treatment with levodopa/carbidopa/entacapone when compared with levodopa/carbidopa improves quality of life in Parkinson's disease (PD) patients with no or minimal, nondisabling motor fluctuations. This is a multicenter, randomized, double‐blind study. One hundred eighty‐four patients on 3 to 4 equal doses of 100/25 to 200/50 mg levodopa/carbidopa or levodopa/benserazide, 0 to 3 hours of nondisabling OFF time over a 48 hour period and no dyskinesia were randomized to levodopa/carbidopa/entacapone or levodopa/carbidopa treatment for 12 weeks. The primary outcome measure was quality of life as assessed by the PDQ‐8. Secondary outcome measures were the UPDRS parts I–IV, and the Wearing Off Card. Treatment with levodopa/carbidopa/entacapone resulted in significantly greater improvements in PDQ‐8 scores compared to treatment with levodopa/carbidopa (mean difference 1.4 points, P = 0.021). Statistically significant improvements were seen predominantly in nonmotor domains (depression, personal relationships, communication, stigma, all P < 0.05; dressing P = 0.056). Patients who were randomly assigned to levodopa/carbidopa/entacapone also showed significantly greater improvement in UPDRS part II scores (P = 0.032) with UPDRS part III scores showing borderline significance. Differences in UPDRS parts I and IV and Wearing Off Card scores were not significant. Treatment with levodopa/carbidopa/entacapone results in improved quality of life compared with levodopa/carbidopa in PD patients with mild or minimal, nondisabling motor fluctuations. © 2007 Movement Disorder Society
Spatial dispersion modelling of SO2 according to the atmospheric circulation in a coastal city: Sfax (Tunisia)
Authors: Khlaifi A. , Dahech S. , Beltrando G. , Ionescu A. , Candau Y.
Published: October 2008

It is well‐known that weather conditions are a crucial factor influencing pollution dispersion. In very industrialized and crowded coast cities, such as Sfax (on the eastern coast of Tunisia), anticyclonic situations contribute to higher levels of pollution due to atmospheric stability, and, in particular, the occurrence of strong thermal inversion layers. The present work deals with the spatial distribution of the principal pollutant (SO2) emitted by the most polluting factory in Sfax. An easy‐to‐implement model (based on the Gaussian model of Pasquil) has been developed to calculate spatial distributions of SO2 in the vicinity of this pollution source. This model has been applied to develop iso‐concentration maps for each weather type at different times of the day. Local breeze situations, notably during the transition from diurnal to nocturnal flow, proved to be the most favourable to the formation of strong pollutant concentrations. The simulated SO2 concentrations were then overlaid on land cover maps, using a GIS, in order to identify the most vulnerable areas. Copyright © 2008 Royal Meteorological Society
Exposure of infants to fumonisins in maize‐based complementary foods in rural Tanzania
Authors: Kimanya Martin E. , Meulenaer Bruno De , Baert Katleen , Tiisekwa Bendantunguka , Van Camp John , Samapundo Simbarashe , Lachat Carl , Kolsteren Patrick
Published: October 2008

Feeding children with maize may expose them to fumonisins (FBs). This study assessed FB exposure for infants consuming maize in Tanzania by modeling maize consumption data (kg/kg body weight (bw)/day) with previously collected total FB contamination (μg/kg) patterns for sorted and unsorted maize harvested in 2005 and 2006. Consumption was estimated by twice conducting a 24 h dietary recall for 254 infants. The exposure assessment was performed with the @RISK analysis software. Of the infants, 89% consumed maize from 2.37 to 158 g/person/day (mean; 43 g/person/day ± 28). Based on the contamination for sorted maize; in 2005, the percentage of infants with FB exposures above the provisional maximum tolerable daily intake (PMTDI) of 2 μg/kg (bw) (26% (95% confidence interval (CI); 23–30)) was significantly higher than the level of 3% (90% CI; 2–12) in 2006. Pooling the datasets for sorted maize from the two seasons resulted in a seemingly more representative risk (10% (95% CI; 6–17)) of exceeding the PMTDI. However, infants who might have consumed unsorted maize would still be at a significantly higher risk (24% (95% CI; 15–34)) of exceeding the PMTDI. Sorting and other good maize management practices should be advocated to farmers in order to minimize FB exposure in rural areas.
Synbiotic promotion of epithelial proliferation by orally ingested encapsulated Bifidobacterium breve and raffinose in the small intestine of rats
Authors: Ishizuka Satoshi , Iwama Ami , Dinoto Achmad , Suksomcheep Akarat , Maeta Kohshi , Kasai Takanori , Hara Hiroshi , Yokota Atsushi
Published: October 2008

We evaluated the effects of Bifidobacterium breve JCM1192T and/or raffinose on epithelial proliferation in the rat small and large intestines. WKAH/Hkm Slc rats (4 wk old) were fed a control diet, a diet supplemented with either encapsulated B. breve (30 g/kg diet, 1.5×107 colony‐forming unit/g capsule) or raffinose (30 g/kg diet), or a diet supplemented with both encapsulated B. breve and raffinose, for 3 wk. Epithelial proliferation in the small intestine, as assessed by bromodeoxyuridine immunohistochemistry, was increased only in the B. breve plus raffinose‐fed group. We determined the number of bifidobacteria in cecal contents using fluorescence in situ hybridization and confirmed the presence of ingested B. breve only in the B. breve plus raffinose‐fed group. This suggests that the ingested B. breve cells used raffinose and were activated in the small intestine, where they subsequently influenced epithelial proliferation. In conclusion, we found a prominent synbiotic effect of encapsulated B. breve in combination with raffinose on epithelial proliferation in rat small intestine but not in large intestine. To our knowledge, this is the first report of a synbiotic that affects epithelial proliferation.
NMR–spectroscopic investigation of o‐nitrosobenzoic acid
Authors: Schaper Klaus
Published: October 2008

The synthesis of o‐nitrosobenzoic acid 2 has been known for more than 100 years, and the photochemical preparation from o‐nitrobenzaldehyde 1 became a textbook example for [1,5]‐hydrogen shifts. However, neither the 1H–NMR spectra nor the 13C{1H}–NMR of this compound have been reported so far. This fact can most likely be attributed to the monomer–dimer equilibrium of the nitrosobenzoic acid, which leads to rather complex, concentration‐dependent NMR spectra. In this paper, we report a thorough investigation of these spectra. In the 13C‐{1H}‐NMR spectra, all 21 lines could be assigned to the monomeric form, the E‐dimer, and the Z‐dimer. Copyright © 2008 John Wiley & Sons, Ltd.
Polyketides from a marine sponge‐derived fungus Mycelia sterilia and proton–proton long‐range coupling
Authors: Hao Gao , Qing‐Hua Zhang , Miao‐Miao Jiang , Jin‐Shan Tang , Cheng‐Du Miao , Kui Hong , Michio Namikoshi , Nai‐Li Wang , Xin‐Sheng Yao
Published: October 2008

A series of polyketide‐originated metabolites (1–5) were isolated from a marine sponge‐derived fungus Mycelia sterilia. Of these, 1–3 were new compounds. Their structures were elucidated by spectroscopic methods as (4R*, 5S*, 6S*, 8S*, 13R*)‐1‐(2,8‐dihydroxy‐1,2,6‐trimethyl‐1,2,6,7,8,8a‐hexahydro‐naphthalen‐1‐yl)‐3‐methoxy‐propan‐1‐one (1), 4,8‐dihydroxy‐7‐(2‐hydroxy‐ethyl)‐6‐methoxy‐3,4‐dihydro‐2H‐naphthalen‐1‐one (2) and 1‐methyl‐naphthalene‐2,6‐dicarboxylic acid (3). In 1, the proton–proton long‐range coupling phenomenon claimed attention and was discussed. Copyright © 2008 John Wiley & Sons, Ltd.
Structure elucidation and NMR assignments for two amide alkaloids from a Mangrove endophytic Fungus (No. ZZF‐22)
Authors: Chen Yiguang , Shao Changlun , Huang Zhongjing , Zhang Ying , Cai Xiaoling , She Zhigang , Zhou Shining , Lin Yongcheng
Published: October 2008

The structure elucidations and complete 1H and 13C NMR assignments are reported for two new natural products: 3‐benzylidene‐8,8a‐dihydroxy‐2‐methyl‐hexahydro‐pyrrolo[1,2‐a]pyrazine‐1,4‐dione(1) and 4‐hydroxy‐6‐(hydroxy‐phenyl‐methyl)‐N‐(3‐methyl‐butyryl)‐nicotinamide (2). Both of these secondary metabolites were isolated from the fermentation medium of a Mangrove endophytic fungus. High resolution electron impact mass spectrometry (HREIMS), FT‐IR Spectroscopy and NMR experiments including gCOSY, gHMQC, gHMBC and NOE were used for determination of the structures and assignments of the amide alkaloids. Copyright © 2008 John Wiley & Sons, Ltd.
Some important aspects in designing high molecular weight poly(L‐lactic acid)–clay nanocomposites with desired properties
Authors: Chowdhury Subhendu Ray
Published: October 2008

BACKGROUND: The main aim of the work reported here was to investigate the effect of clay aspect ratio and functional edge group on the dispersion, degree of order of clays and interfacial strength of high molecular weight poly(L‐lactic acid) (PLLA)–clay amorphous nanocomposites and consequently their properties. Three kinds of clays (two montmorillonites (SMMTC18 and NMMTC18) and one fluoro‐mica (MC18) with the same surfactant) were used to synthesize three amorphous nanocomposites. Thermomechanical properties, permeability, etc., were compared among composites and with pure PLLA.

RESULTS: From X‐ray diffraction and transmission electron microscopy, both MMTs with lower aspect ratio showed better dispersion and greater degree of disorder, which led to stronger interfacial strength and consequently higher storage modulus than MC18‐based composites. All composites showed better properties than pure PLLA. The oxygen barrier efficiencies of SMMTC18‐ and NMMTC18‐based composites were higher than that of the MC18‐based composites. Due to the highest exposed area and probably stronger interactions, SMMTC18 had the highest nucleating efficiency.

CONCLUSIONS: Along with aspect ratio, dispersion and degree of intercalation, the interfacial strength of composites and degree of order of clays are also important issues for property development. Compared to reported results in the literature, our amorphous composites showed less of an improvement of thermomechanical properties as real reinforcement was solely from clays. Copyright © 2008 Society of Chemical Industry
Effect of blend composition on the morphology development of electrospun fibres based on PAN/PMMA blends
Authors: Hong Chang Kook , Yang Kap Seung , Oh Seung Hyun , Ahn Jou‐Hyeon , Cho Baik‐Hwan , Nah Changwoon
Published: October 2008

BACKGROUND: The aim of the work presented was to determine the morphology development and relevant change in fibre diameter of a binary polymer blend system during an electrospinning process. The size of the fibre diameter is one of the important factors determining the general properties of non‐woven mats formed from electrospun fibres.

RESULTS: The morphology and diameter of electrospun polyacrylonitrile (PAN)/poly(methyl methacrylate) (PMMA) blends were investigated as a function of blend ratio using scanning electron microscopy. The diameter of the electrospun PAN/PMMA fibres decreased with increasing PMMA content up to 50 wt%, and then increased again with further increase of PMMA. After thermal treatment, the fibres shrank, and an irregularly shaped morphology was observed.

CONCLUSION: The electrospinning of incompatible PAN/PMMA blends leads to a microphase‐separation morphology of fibres. A phase inversion occurs at a PMMA content of between 50 and 75 wt%. Due to the phase inversion, the fibre diameter shows a minimum value at the relevant composition. Copyright © 2008 Society of Chemical Industry
History of accelerated and qualification testing of terrestrial photovoltaic modules: A literature review
Authors: Osterwald C. R. , McMahon T. J.
Published: October 2008

We review published literature from 1975 to the present for accelerated stress testing of flat‐plate terrestrial photovoltaic (PV) modules. An important facet of this subject is the standard module test sequences that have been adopted by national and international standards organizations, especially those of the International Electrotechnical Commission (IEC). The intent and history of these qualification tests, provided in this review, shows that standard module qualification test results cannot be used to obtain or infer a product lifetime. Closely related subjects also discussed include: other limitations of qualification testing, definitions of module lifetime, module product certification, and accelerated life testing. Copyright © 2008 John Wiley & Sons, Ltd.
Recovery of silicon from kerf loss slurry waste for photovoltaic applications
Authors: Wang T. Y. , Lin Y. C. , Tai C. Y. , Fei C. C. , Tseng M. Y. , Lan C. W.
Published: October 2008

The constantly rising price of silicon feedstock has been the most important factor preventing photovoltaic (PV) energy from reaching grid parity. On the other hand, large amount of silicon gets wasted during slicing. We report a promising approach to recycle kerf loss silicon from cutting slurry waste for solar cell applications. Silicon carbide (SiC) and metal impurities were successfully removed by chemical/ physical processing from the slurry waste to recover solar grade silicon. The effects of centrifugation using heavy fluids and high‐temperature treatment in the removal of SiC particles are discussed in detail. Ingots from the recycled silicon were grown by using directional solidification. The average resistivity and minority carrier lifetime of the grown crystals were found to be about 0·7 Ω cm and 1·02 µs, respectively, which were close to the original sawing silicon ingots. Solar cells using multi‐crystalline wafers of recovered silicon were fabricated and the best energy conversion efficiency was found to be 12·6% comparable to those from the high‐purity silicon. Copyright © 2008 John Wiley & Sons, Ltd.
Proteomic analysis of protein S‐nitrosylation
Authors: Torta Federico , Usuelli Vera , Malgaroli Antonio , Bachi Angela
Published: October 2008

Nitric oxide (NO) produces covalent PTMs of specific cysteine residues, a process known as S‐nitrosylation. This route is dynamically regulated and is one of the major NO signalling pathways known to have strong and dynamic interactions with redox signalling. In agreement with this scenario, binding of NO to key cysteine groups can be linked to a broad range of physiological and pathological cellular events, such as smooth muscle relaxation, neurotransmission and neurodegeneration. The characterization of S‐nitrosylated residues and the functional relevance of this protein modification are both essential information needed to understand the action of NO in living organisms. In this review, we focus on recent advances in this field and on state‐of‐the‐art proteomic approaches which are aimed at characterizing the S‐nitrosylome in different biological backgrounds.
Quantitative phosphoproteome analysis of a mouse liver cell line reveals specificity of phosphatase inhibitors
Authors: Pan Cuiping , Gnad Florian , Olsen Jesper V. , Mann Matthias
Published: October 2008

The liver is a central organ involved in many aspects of physiology and disease. Signaling properties of hepatocytes, the main liver cell type, are of special interest in metabolic diseases and in regeneration. For this reason we investigated the phosphoproteome of the mouse liver cell line Hepa1‐6 by stable isotope labeling by amino acids in cell culture (SILAC) and high resolution MS. Using stringent statistical evaluation criteria, we obtained 5433 phosphorylation sites on 1808 proteins. The phosphoproteome encompasses all major protein classes, including a large number of transcription factors. We compared control and phosphatase inhibitor treated cells by SILAC. This enabled ready identification of in vivo phosphorylation sites by sequencing the more abundant, inhibitor induced version of the peptide while still observing the endogenous version. We employed a mixture of pervanadate for blocking protein tyrosine phosphatases (PTPs) and calyculin A and deltamethrin for blocking the activities of serine/threonine phosphatases. Interestingly, these commonly used inhibitors in standard concentrations affected only 28% of the phosphopeptides by at least two‐fold. The unaffected sites may be substrates of phosphatases that are not efficiently inhibited, have slow kinetic or sites that are almost stoichiometric in normally growing cells. Finally, we devised a triple labeling strategy comprising control cells, stimulated cells, and phosphatase treated cells to derive an upper bound on phosphorylation occupancy.