bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of organic matter and initial carbon–nitrogen ratio on the bioconversion of volatile fatty acids from sewage sludge
Authors: Liu Xiaoling , Liu He , Chen Yiyang , Du Guochen , Chen Jian 
Published: March 2008

AbstractBACKGROUND: The biodegradable organic matter and the initial carbon–nitrogen ratio can be substantially different in different batches of sewage sludge, which results in a difference in the acidification efficiency of sludge. Using sewage sludge from three different sources, batch tests were performed to analyze the relationship between volatile fatty acids (VFAs) and consumed organic matter, and to investigate the effects of initial carbon–nitrogen (C/N) ratio on the acidification efficiency of sludge.RESULTS: Maximum yields of 152.1 ± 3.5 mg total VFAs‐COD per gram volatile solid (VS) added and 22.4 ± 1.2 mg butyric acid‐COD g−1 VS added were obtained from the sludge with the highest initial C/N ratio. Statistical analysis indicated that protein was the major substrate for the produced VFAs. The sludge with the least initial C/N ratio (5.01) had the least yield, and only acetic acid, which was also mainly related to protein, was detected.CONCLUSION: The initial carbon–nitrogen ratio was one of the most important factors influencing the distribution patterns of VFAs and the yield of total VFAs produced from sewage sludge. A high C/N ratio could not only improve the yield of total VFAs but also enhance the yield of butyric acid. Copyright © 2008 Society of Chemical Industry
Photocatalytic degradation of methyl tert‐butyl ether (MTBE) in contaminated water by ZnO nanoparticles
Authors: Eslami Akbar , Nasseri Simin , Yadollahi Bahram , Mesdaghinia Alireza , Vaezi Foroogh , Nabizadeh Ramin , Nazmara Shahrokh 
Published: March 2008

AbstractBACKGROUND: Over the past several decades methyl tert‐butyl ether (MTBE) as additive to gasoline, intended to either boost ratings of fuel or to reduce air pollution, has been accepted worldwide. Since MTBE has high water solubility, the occurrence of fuel spills or leaks from underground storage tanks or transferring pipeline has led to the contamination of natural waters. In this study the degradation of aqueous MTBE at relatively high concentrations was investigated by a UV‐visible/ZnO/H2O2 photocatalytic process. The effects of important operational parameters such as pH, amount of H2O2, catalyst loading and irradiation time were also investigated. Concentration of MTBE and intermediates such as tert‐butyl formate and tert‐butyl alcohol were measured.RESULTS: Time required for complete degradation increased from 20 to 150 min when the initial concentration was increased from 10 to 500 mg L−1. The first‐order rate constants for degradation of MTBE were estimated to be 0.183–0.022 min−1 as the concentration increased from 10 to 500 mg L−1. Study of the overall mineralization monitored by total organic carbon analysis showed that at an initial concentration of 100 mg L−1 MTBE complete mineralization was obtained after 100 min under UV‐visible/ZnO/H2O2 photocatalysis.CONCLUSION: The data presented in this paper clearly indicated that UV‐visible/ZnO/O2 as an advanced oxidation process provides an efficient treatment alternative for the remediation of MTBE‐contaminated waters. Copyright © 2008 Society of Chemical Industry
Improvement of enantioselectivity and stability of Klebsiella oxytoca hydrolase immobilized on Eupergit C 250L
Authors: Wang Pei‐Yun , Tsai Shau‐Wei , Chen Teh‐Liang 
Published: March 2008

AbstractBACKGROUND: A simple procedure was employed to covalently immobilize a Klebsiella oxytoca hydrolase (SNSM‐87) onto epoxy‐activated supports of Eupergit C 250L via multipoint covalent attachment. The resultant biocatalyst was explored for the hydrolytic resolution of a variety of (R,S)‐2‐hydroxycarboxylic acid ethyl esters.RESULTS: With the hydrolytic resolution of (R,S)‐ethyl mandelate in biphasic media as the model system, optimal conditions of 55 °C, pH 6 buffer and isooctane as the organic phase were selected for improving the enzyme stability (activity retained from 10% to 50% at 96 h) and enantioselectivity (VSVR−1 value enhanced from 44 to 319) in comparison to the performance of free enzyme. Moreover, the immobilized enzyme retained its activity and enantioselectivity after eight cycles of hydrolysis at 55 °C. When applying the resolution process to other (R,S)‐2‐hydroxycarboxylic acid ethyl esters, 2.4‐ to 4.0‐fold enhancements of the enantioselectivity in general were obtainable.CONCLUSIONS: The enantioselectivity enhancement, good reusability and easy recovery after reaction indicate that the immobilized SNSM‐87 may have the potential as an industrial biocatalyst for the preparation of optically pure 2‐hydroxycarboxylic acids. Copyright © 2008 Society of Chemical Industry
Removal of dimethyl sulfide in a thermophilic membrane bioreactor
Authors: Luvsanjamba Munkhtsetseg , Kumar Amit , Van Langenhove Herman 
Published: March 2008

AbstractBACKGROUND: Several sources such as the paper and pulp industry and waste treatment plants emit waste gases containing volatile organic sulfur compounds at elevated temperature. Since cooling the hot gases increases the operational cost of biological reactors, application of thermophilic microorganisms could be a cost‐effective solution. The objectives of this study were to investigate the possibility of removal of dimethyl sulfide from waste gases under thermophilic conditions (52 °C) in a membrane bioreactor and to examine the long‐term stability of the reactor at elevated temperature. The effects of operating conditions such as gas residence time, nutrient supply, temperature decrease and short‐term shutdown on elimination capacity were investigated.RESULTS: A maximum elimination capacity of 54 g m−3 h−1 (0.108 g m−2 h−1) was obtained at a mass loading rate of 64 g m−3 h−1 (0.128 g m−2 h−1) with a removal efficiency of 84% at a gas residence time of 24 s. The long‐term operation of the thermophilic membrane bioreactor was followed for 9 months. Although the removal efficiency decreased to 50% after 3 months of continuous operation, it recovered (>96%) after the excess biomass was removed by applying high‐velocity liquid recirculation.CONCLUSION: This study demonstrated that the dimethyl sulfide removal is possible in a thermophilic membrane bioreactor with an elimination capacity of 54 g m−3 h−1 (0.108 g m−2 h−1) at a gas residence time of 24 s. Copyright © 2008 Society of Chemical Industry
Activation of tumor‐specific T cells by dendritic cells expressing the NY‐ESO‐1 antigen after transfection with the cationic lipophosphoramide KLN5
Authors: Le Gallo Matthieu , Toutirais Olivier , Montier Tristan , Cabillic Florian , Bouet Françoise , Delépine Pascal , Lehn Pierre , Jotereau Francine , Catros Véronique 
Published: March 2008

AbstractBackgroundGenetic modification of human monocyte‐derived dendritic cells (DC) with cDNA sequences encoding tumor‐associated antigens (TAA) is a promising strategy for cancer immunotherapy. The present study aimed to develop a nonviral gene transfer method based on the use of the cationic lipophosphoramide reagent, KLN‐5, as an alternative to the commonly used viral vectors.MethodsFirst, the efficiency of KLN5 for gene transfection into DC was investigated using the green fluorescent protein (GFP) reporter gene. The highest transfection efficiency/cell viability ratio was determined by flow cytometry. Next, DC were transfected with a plasmid encoding NY‐ESO‐1, a TAA expressed in numerous cancers, according to the transfection protocol previously established with the GFP reporter. Transfected DC were then co‐cultured with a CD8+ NY‐ESO‐1 specific HLA‐A*02.01 T cell clone to control their ability to correctly process and present the corresponding epitope in the HLA‐A*02.01 context. Finally, T cell activation was assessed via flow cytometry‐based detection of interferon‐γ production.ResultsAn optimal KLN5/plasmid DNA ratio allowing both significant transgene expression and high viability of DC could be determined. Under the established experimental conditions, antigen processing and presentation of the immunodominant (SLLMWITQC157–165) epitope in the HLA‐A*0201 context was demonstrated by activation of the NY‐ESO‐1‐specific CD8+ T cell clone.ConclusionsKLN5‐based gene transfection into DC allows the efficient induction of TAA presentation and may thus represent a novel attractive nonviral approach for cancer vaccination. Copyright © 2008 John Wiley & Sons, Ltd.
Downstream utrophin enhancer is required for expression of utrophin in skeletal muscle
Authors: Tanihata Jun , Suzuki Naoki , Miyagoe‐Suzuki Yuko , Imaizumi Kazuhiko , Takeda Shin'ichi 
Published: March 2008

AbstractBackgroundDuchenne muscular dystrophy is caused by the absence of the muscle cytoskeletal protein dystrophin. Utrophin is an autosomal homologue of dystrophin, and overexpression of utrophin is expected to compensate for the dystrophin deficit. We previously reported that the 5.4‐kb 5′‐flanking region of the utrophin gene containing the A‐utrophin core promoter did not drive transgene expression in heart and skeletal muscle. To clarify the regulatory mechanism of utrophin expression, we generated a nuclear localization signal‐tagged LacZ transgenic (Tg) mouse, in which the LacZ gene was driven by the 129‐bp downstream utrophin enhancer (DUE) and the 5.4‐kb 5′‐flanking region of the utrophin promoter.MethodsTwo Tg lines were established. The levels of transgene mRNA expression in several tissues were examined by reverse transcriptase‐polymerase chain reaction (RT‐PCR) and quantitative RT‐PCR. Cryosections of several tissues were stained with haematoxylin and eosin and X‐gal.ResultsThe transgene expression patterns were consistent with endogenous utrophin in several tissues including heart and skeletal muscle. Transgene expression was also up‐regulated more in regenerating muscle than in nonregenerating muscle. Moreover, utrophin expression was augmented in the skeletal muscle of DUE Tg/dystrophin‐deficient mdx mice through cross‐breeding experiments. We finally established cultures of primary myogenic cells from this Tg mouse and found that utrophin up‐regulation during muscle differentiation depends on the DUE motif.ConclusionsOur results showed that DUE is indispensable for utrophin expression in skeletal muscle and heart, and primary myogenic cells from this Tg mice provide a high through‐put screening system for drugs that up‐regulate utrophin expression. Copyright © 2008 John Wiley & Sons, Ltd.
Synergistic antitumoral effects of human telomerase reverse transcriptase‐mediated dual‐apoptosis‐related gene vector delivered by orally attenuated Salmonella enterica Serovar Typhimurium in murine tumor models
Authors: Fu Wei , Chu Liang , Han Xinwei , Liu Xinyuan , Ren Daming 
Published: March 2008

AbstractSalmonella enterica Serovar Typhimurium (S. typhimurium), a facultative anaerobe, has been reported to be capable of both selectively amplifying and expressing exogenous genes within tumors. In addition, previous studies have demonstrated that the human telomerase reverse transcriptase (hTERT) promoter could confine gene expression strictly to the telomerase‐positive cancer cells. In the present study, we used attenuated S. typhimurium as a carrier to deliver a eukaryotic expression vector (pSNhTS) that contains the second mitochondria‐derived activator of caspases (Smac) and tumor necrosis factor‐related apoptosis‐inducing ligand (TRAIL) genes under the control of the hTERT promoter. The results of in vitro experiments showed that Smac could enhance TRAIL‐induced apoptosis in tumor cells and the hTERT promoter could drive specific gene expression in tumor cells, but not in normal cells. In vivo data in mice indicated that salmonella‐mediated exogenous gene expression could persist for at least 14 days in tumors. Furthermore, S.L./SNhTS (S. typhimurium carrying the pSNhTS) was orally administered into mice bearing tumors, and its antitumoral effect was evaluated. It was observed that S.L./SNhTS significantly inhibited tumor growth by 70–90% and prolonged the survival of mice. This strong antitumoral activity achieved by S.L./SNhTS was due to the synergistic antitumoral properties of Smac and TRAIL‐recombinant proteins. Our data also support the idea that the hTERT promoter could be an excellent candidate for cancer‐specific therapy and S. typhimurium appeared to be a promising strategy for the treatment of solid tumors. Copyright © 2008 John Wiley & Sons, Ltd.
The cyclo‐oxygenase 2 promoter is induced in nontarget cells following adenovirus infection, but an AU‐rich 3′‐untranslated region destabilization element can increase specificity
Authors: Särkioja Merja , Hakkarainen Tanja , Eriksson Minna , Ristimäki Ari , Desmond Renee A. , Kanerva Anna , Hemminki Akseli 
Published: March 2008

AbstractBackgroundCyclo‐oxygenase 2 (Cox‐2) is expressed in many types of tumors, but typically undetectable in normal tissues. However, Cox‐2 is known to be induced following infection by many microbial agents, which might threaten the tumor selectivity of the Cox‐2 promoter in the context of virotherapy or viral gene delivery. Cox‐2 expression is regulated in part post‐transcriptionally by stimulation or inhibition of mRNA degradation by 3′‐untranslated region (3′‐UTR) AU‐rich elements. In the present study, we investigated the induction of the Cox‐2 promoter both in normal and tumor cells after adenovirus infection and explored the utility of AU‐rich elements for regaining promoter selectivity.MethodsNontumor and tumor cells were transfected in vitro and in vivo with plasmids containing the Cox‐2 or cytomegalovirus immediate early promoter driving luciferase (with or without 3′‐UTR elements) followed by adenoviral infection. Selectivity and activity of the promoters and 3′‐UTR elements were analysed by luciferase assay and in‐vivo imaging.ResultsThe Cox‐2 promoter was induced in both normal and tumor cells following infection with E1 containing replicative adenoviruses but not in the absence of E1. Utilization of AU‐rich elements counteracted promoter induction in vitro and in vivo in nonmalignant cells but not in cancer cells, thus increasing the selectivity of the approach ten‐fold without loss of potency.ConclusionsAdenoviral infection induces the Cox‐2 promoter in normal and tumor cells, which might compromise specificity of the promoter. Utilization of AU‐rich destabilization elements can rescue the tumor selectivity of the promoter. Copyright © 2008 John Wiley & Sons, Ltd.
Mapping a topographic global solar radiation model implemented in a GIS and refined with ground data
Authors: Pons Xavier , Ninyerola Miquel 
Published: March 2008

AbstractThis study proposes a methodology to compute solar radiation values on the Earth surface on a monthly and annual basis and taking into account the relief, which is not an usual approach although it has enormous importance for environmental studies. It consists of two steps: a computational, physically‐based model (potential solar radiation) and a refining through meteorological data (interpolated solar radiation). The potential solar radiation model allows computing the incident energy assuming uniform atmospheric standard optical density. The only information required is a Digital Elevation Model (DEM, 180 m resolution in our case) and a number of meteorological stations providing global solar radiation data (74 in our case). This model, implemented into the MiraMon Geographic Information System (GIS), takes into account astronomical, atmospheric and geographical factors. Atmospheric effects are considered through correctors obtained by comparing the potential values with the observed at the meteorological stations. The resulting monthly correctors have been spatially interpolated to build up anomaly maps, which allow to obtain a refined solar radiation cartography. The potential model has proven to be very precise as it gives results close to the interpolated radiation values, allowing a conversion to interpolated solar radiation maps with errors of 7.3% (March), 6.1% (June), 6.4% (September) and 13.1% (December) computed from a leave‐one‐out cross‐validation. These results are always better than those obtained by classical interpolators, and still better if the process is run on the rugged terrain areas. A sensitivity analysis estimates the influence of the DEM quality on the model, concluding that an RMS error of 8 m in the DEM heights represents an RMS error of 133 kJ·m−2·day−1(mean monthly) on the results. Finally, we have applied the model to obtain the 12‐monthly (based on daily average) global solar radiation maps of Catalonia (NE of Iberian Peninsula) as well as the annual one. Copyright © 2008 Royal Meteorological Society
Raman spectroscopy as a tool to diagnose the impacts of combustion and greenhouse acid gases on properties of Built Heritage
Authors: Sarmiento A. , Maguregui M. , Martinez‐Arkarazo I. , Angulo M. , Castro K. , Olazábal M. A. , Fernández L. A. , Rodríguez‐Laso M. D. , Mujika A. M. , Gómez J. , Madariaga J. M. 
Published: March 2008

AbstractThe effects of the dry and wet acid deposition from both combustion and greenhouse gases (mainly CO2, SOx and NOx) can be observed in the stones, mortars, bricks and decorative materials used in Built Heritage elements. Those deposition phenomena have greater effects in urban atmospheres, especially in medium or highly polluted ones. Most of the products formed as a consequence of decaying are alkaline and alkaline‐earth oxoanions, which show, in general, a medium or high Raman scattering. The coupling of the experimental evidence (the detection of some metal–oxoanionic compounds by Raman spectroscopy) with the knowledge of chemical equilibrium is presented in this work as a tool to diagnose the impacts of CO2, SOx and NOx on the properties of Built Heritage. The compounds identified by Raman spectroscopy on different materials sampled in buildings of the Metropolitan Bilbao area (North Spain) included nitrocalcite, nitratine, nitromagnesite, nitrobarite as well as gypsum and soot as part of the black crust on carbonate‐based materials, whereas calcite, natron, nitratine and mirabillite were recognised as composition of the white efflorescence in non‐carbonate materials and mortars. An overall degradation pathway is proposed to explain the formation of each decayed compound as a function of the original characteristic material. Copyright © 2008 John Wiley & Sons, Ltd.
Effects of defatted dried roselle (Hibiscus sabdariffa L.) seed powder on lipid profiles of hypercholesterolemia rats
Authors: Hainida Emmy , Ismail Amin , Hashim Normah , Mohd.‐Esa Norhaizan , Zakiah Ainul 
Published: March 2008

AbstractBACKGROUND: In vivo investigations were made of the effect of defatted dried roselle seed powder (DRS) on the lipid profiles of rats with induced hypercholesterolemia. The two‐batch sample consisted of 23 and 20 Sprague‐Dawley male rats randomly divided into four groups and fed with four different diets. The first batch of rats was fed with normal, hypercholesterol, hypercholesterol + 10 g kg−1 (w/w) DRS and hypercholesterol + 20 g kg−1 (w/w) DRS diets. The second batch of rats was fed with normal, hypercholesterol, hypercholesterol + 50 g kg−1 (w/w) DRS and hypercholesterol + 150 g kg−1 (w/w) DRS diets. Treatments were given for a total of 5 weeks.RESULTS: Results indicated that the addition of 10 g kg−1 and 20 g kg−1 of DRS did not significantly lower the plasma total cholesterol (TC) levels. In contrast, 50 g kg−1 and 150g kg−1 DRS significantly lowered (P < 0.05) the TC and low density lipoprotein cholesterol (LDL‐C) levels.CONCLUSION: The addition of 50 g kg−1 and 150 g kg−1 DRS showed potential hypocholesterolemic effects. Furthermore, these findings indicated that protein, lipid and dietary fibre were high in the seed powder. Copyright © 2008 Society of Chemical Industry
Nutrient digestibility response to graded dietary levels of sodium chloride in weanling pigs
Authors: Yin Yu‐long , Huang Chunhong , Wu Xin , Li Tiejun , Huang Ruilin , Kang Ping , Hu Qin , Chu Wuying , Kong Xiangfeng 
Published: March 2008

AbstractBACKGROUND: Sodium (Na+), chloride (Cl−) and phosphorus (Pi) are involved in a number of metabolic and physiological processes in the body, and these mineral elements must be supplied to the animal via the diet. The intention of this study was to evaluate the effect of dietary supplementation with different levels of sodium chloride (0.1, 0.2, 0.3, 0.4, 0.5 and 0.6% NaCl) on apparent and true P digestibility (APD and TPD) and dry matter (DM), crude protein (CP) and calcium (Ca) digestibility in weanling pigs.RESULTS: Dietary NaCl had a quadratic effect on both APD and TPD (P < 0.05) but not on DM, CP and Ca digestibility (P > 0.05). At an NaCl concentration of 0.41% the APD and TPD values were 41.5 and 53.3% respectively.CONCLUSION: These results suggest that a high level of dietary Na+ may enhance P absorption and improve its digestibility by coupling Na+ transportation to Pi absorption via the energy‐requiring Na+/Pi co‐transporter. Copyright © 2008 Society of Chemical Industry
Preparation and cure behavior of organoclay‐modified allyl‐functional benzoxazine resin and the properties of their nanocomposites
Authors: Agag Tarek , Takeichi Tsutomu 
Published: March 2008

AbstractA new type of polybenzoxazine‐clay nanocomposites were prepared by the in‐situ polymerization of allyl‐functional benzoxazine monomer, bis(3‐allyl‐3,4‐dihydro‐2H‐1,3‐benzoxazinyl)isopropane (B‐ala), in the presence of two different types of organoclay, allyldimethylstearylammonium‐montmorillonite and propyldimethylstearylammonium‐montmorillonite. The organoclays were mixed with molten B‐ala, followed by pouring into glass mold and then gradual curing up to 250°C. DSC and IR were used to follow the cure behavior of B‐ala in the presence of organoclay, indicating that organoclays catalyzed the ring opening of cyclic benzoxazine structure. The XRD of the nanocomposites showed featureless patterns, suggesting the exfoliation of the organoclay into the matrix. The viscoelastic properties of the hybrids showed that the glass transition temperatures (Tg) of the nanocomposites shifted to lower temperature in the presence of small amount of organoclay, but Tg started to increase with the increase of the organoclay content. This result suggests that, in the presence of organoclay, the curing reaction of ally and benzoxazine occurred in a different way, resulting in a different network structure. However, the presence of dispersed layered silicates into the matrix enhanced the thermal stability over the neat thermoset resin. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers