bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cloning and functional expression of rAQP9L a new member of aquaporin family from rat liver
Authors: Ko Shigeru B. H. , Uchida Shinichi , Naruse Satoru , Kuwahara Michio , Ishibashi Kenichi , Marumo Fumiaki , Hayakawa Tetsuo , Sasaki Sei 
Published: July 2007

AbstractA new aquaporin was isolated from rat liver based on homology to known aquaporins. A 1408 bp cDNA was sequenced (designated rAQP9L) with a 885 bp open reading frame encoding a 295 amino acid hydrophobic protein, rAQP9L has the greatest amino‐acid sequence identity with human AQP9 (75 %) and a less homology with AQP3 (49 %) and AQP (47 %). Northern blot analysis indicated a 1.4‐kb transcript expressed strongly in liver>testis>brain=lung. Expression of rAQP9L cRNA in Xenopus oocytes increased osmotic water permeability by 6‐folds which was inhibited by 0.3 mM mercury chloride by 42 %. rAQP9L also facilitated glycerol and urea transport by 2‐ and 5‐folds, respectively. The large discrepancy of tissue distribution between hAQP9 and rAQP9L suggest that rAQP9L is a new aquaporin, which is involved in transport of urea as well as water in liver.
Protein folding as a nonlinear nonequilibrium thermodynamic process
Authors: Popov E. M. 
Published: July 2007

AbstractBiofurcational theory of protein folding is developed describing the process of formation of protein native structure as a sequence of non‐equilibrium irreversible fluctuations, specific for a particular protein. The model gives explaination to all characteristic features of the folding process: stochastic mechanism, short time and precision of proteins self‐assembling. A constructiwe role of entropy in the formation of a highly ordered structure out of disorder is discussed. A numerical method of a priori calculations of polypeptide structures basing on principles of bifractional folding model is presented.
Superoxide anion and hydroxyl radical scavenging activities of vegetable extracts measured using electron spin resonance
Authors: Kaneyuki Takao , Noda Yasuko , Traber Maret G. , Mori Akitane , Packer Lester 
Published: July 2007

AbstractRadical scavenging by reconstituted lyophilized powders of water extracts from 16 common vegetables was measured using electron spin resonance (ESR) with 5,5‐dimethyl‐1‐pyrroline‐N‐oxide (DMPO), hydroxyl radicals, (·OH) or superoxide anion radicals (02·‐), as DMPO‐OH or DMPO‐OOH spin adducts. On a dry weight basis, eggplant, and red, yellow and green bell pepper extracts showed potent superoxide anion radical scavenging activities (SOD‐like activities). Ascorbate oxidase‐ or heat‐treatments, decreased SOD‐like activities in bell pepper extracts suggesting that ascorbate accounts for much of their free radical scavenging activity. Eggplant epidermis extract exhibited the most potent hydroxyl radical scavenging and SOD‐like activities. Eggplant SOD‐like activity did not decrease after ascorbate oxidase treatment, but decreased following ultrafiltration demonstrating that SOD‐like activity is partially due to high molecular weight substances. Nasunin, an anthocyanin in eggplant epidermis, showed markedly potent superoxide anion radical scavenging activity, while it inhibited hydroxyl radical generation probably by chelating ferrous ion.
The Resistance Continues: a social movement in the 1970s
Authors: Cooke Philip 
Published: July 2007

SummaryIn the 1970s a group of ex-partisans founded the Resistenza Continua social movement. This article traces the origins and history of the movement and explores its contacts with other similar neo-Resistance groups. Though Resistenza Continua was clearly not a movement of great consequence, an analysis of it sheds a useful light on the strengths and weaknesses of the Resistance tradition.
Plexins, Semaphorins, and Scatter Factor Receptors: A Common Root for Cell Guidance Signals?
Authors: Artigiani Stefania , Comoglio Paolo M. , Tamagnone Luca 
Published: July 2007

AbstractSemaphorins, the plexin family of semaphorin receptors, and scatter factor receptors share evolutionarily conserved protein modules, such as the semaphorin domain and Met Related Sequences (MRS). All these proteins also have in common a role in mediating cell guidance cues. During development, scatter factor receptors control cell migration, epithelial tubulogenesis, and neurite extension. Semaphorins and their receptors are known signals for axon guidance; they are also suspected to regulate developmental processes involving cell migration and morphogenesis, and have been implicated in immune function and tumor progression. Scatter factors and secreted semaphorins are diffusible ligands, whereas membrane‐bound semaphorins signal by cell‐cell interaction. Cell guidance control by semaphorins requires plexins, alone or in a receptor complex with neuropilins. Semaphorins, besides their role in axon guidance, are expected to have multiple functions in morphogenesis and tissue remodeling by mediating cell‐repelling cues through plexin receptors.
Internet‐based scanning of the competitive environment
Authors: Rajaniemi Katja 
Published: July 2007

PurposeAdjusting a company to its competitive environment is often done without proper knowledge of the competitive environment. This paper seeks to describe methods and tools that could be used to improve internet‐based scanning of the competitive environment. In addition, the paper aims to describe an example where such methods and tools are used.Design/methodology/approachExisting literature on environmental scanning, competitive intelligence, and benchmarking is reviewed to brief the theoretical background, and to find new ideas to improve scanning of the competitive environment. Using theory‐building approach, the research is based on constructive methodology. The construction is done in ABB Corporate Research, in the Business Technology Portals Project.FindingsExperts scan the environment using the advanced tools, interviews and knowledge sharing, and managers mainly scan by discussing with other people. Modern search engines can be used to build advanced tools that enhance competitive environment scanning and benchmarking on screening level. Search engines acquire and analyze information from the internet, e.g. from news, company, internet pages, patents, and databases. The methods reduce the time needed for acquiring information, enabling people to concentrate on analyzing the information.Research limitations/implicationsFor researchers, the paper provides a literature review of the topic with an innovative construction.Practical implicationsFor practitioners, the paper provides an example of framework, methods and tools that can be used to scan the competitive environment.Originality/valueThe theoretical background has been innovatively applied to construct and to deploy very pragmatic tools that enhance scanning the competitive environment.
Smoking is associated with first‐ever incidence of mental disorders: a prospective population‐based study
Authors: Cuijpers Pim , Smit Filip , Ten Have Margreet , De Graaf Ron 
Published: July 2007

ABSTRACTAims  It is well established that tobacco use is associated with mental disorders. However, the association between tobacco use and mental disorders has not yet been examined sufficiently in prospective, population‐based studies. The current study is aimed at examining whether smoking is associated with first‐ever incidence of mental disorders.Design, setting and participants  We conducted a prospective, population‐based epidemiological study (the Netherlands Mental Health Survey and Incidence Study: NEMESIS) in which a representative sample of adults aged 18–64 years (n = 7076) were interviewed to establish the presence of a broad range of mental disorders. We re‐interviewed them at 1 year (n = 5618; response 79.4%) and 3 years (n = 4796; 67.8%) after baseline.Measurements  The presence of mental disorders was assessed according to DSM‐III‐R criteria with the Composite International Diagnostic Interview (CIDI), which was administered by trained lay interviewers. Tobacco use was assessed by asking respondents whether they had smoked in the past year, and how many cigarettes they smoked.Findings  Subjects who smoked but never had a mental disorder in their life, had an increased risk of developing a mental disorder (P < 0.01), and this remained significant after correcting for major risk indicators of mental disorders.Conclusions  Smoking is associated not only with the prevalence, but also with first‐ever incidence of mental disorders. More research is needed to study the causal pathways.
The role of glitazones in management of type 2 diabetes. A DREAM or a nightmare?
Authors: Lindberg M. , Astrup A. 
Published: June 2007

SummaryGlitazones have been introduced as second‐step medication for type 2 diabetics, and today rosiglitazone and pioglitazone are blockbuster drugs. However, glitazones may have important adverse effects that outweight their beneficial effect on insulin resistance and glycemia. The larger trials have shown that glitazones produce a weight gain of 4–5 kg over 3–4 years of treatment, and the weight gain cannot be explained by fluid retention. Moreover, the risk of myocardial infarction is increased by 43% by rosiglitazone, and there are clear indications of increased risk of heart failure. Furthermore, there are studies to suggest that glitazones also increase the risk of fractures, whereas an increased cancer risk is not supported. In conclusion, given the increased cardiovascular risk, and that a weight gain of few kg can increase risks of cancer of the breast, colon, prostate and endometrium, the use of glitazones should be questioned. There is a need for more safe and weight neutral drugs to treat type 2 diabetes.
Comparative study of patch test using traditional method vs. prior skin abrading
Authors: Fernandes MFM , De Mello JF , Pires MC , Vizeu MCM 
Published: June 2007

SummaryBackground  The patch test is an essential procedure for the investigation of aetiologic diagnosis of allergic contact dermatitis, although it is not yet able to fully reproduce the events of the initial site of contact with the allergen.Objectives  The aims of the present study are (i) to assess whether removal of the superficial corneous layer results in test positivity differences vs. the traditional technique, (ii) to assess the probable and/or possible and past and/or present sensitivity and relevance for each method, and (iii) to compare specific relevance of nickel sulphate for each method.Results  Concordance of positive reactions was 75.9% (66 of 87), with 21.8% (19 of 87) positivity results on the abraded side only and 2.3% (2 of 87) on the unabraded side (P < 0.05). Concordance of the substances with probable and/or possible and past and/or present relevance was 77.3% (58 of 75) for the abraded side and 21.3% (16 of 75) and 1.3% (1 of 75) for the unabraded side (P < 0.05). Analysis of isolated relevance for nickel sulphate showed 95.6% (22 of 23) concordance.Conclusions  (i) We found a greater number of positive substances on the abraded side, and when only the 2 + and 3 + reactions were considered, greater relative discordance was also observed; (ii) relevance analysis revealed a statistically significant difference between the two methods; (iii) differences in nickel sulphate test positivity and relevance for the two methods did not reach statistical significance.
Evaluating the Effects of Chlortetracycline on the Proliferation of Antibiotic-Resistant Bacteria in a Simulated River Water Ecosystem
Authors: Muñoz-Aguayo Jeannette , Lang Kevin S. , LaPara Timothy M. , González Gerardo , Singer Randall S. 
Published: July 2007

ABSTRACT

Antibiotics and antibiotic metabolites have been found in the environment, but the biological activities of these compounds are uncertain, especially given the low levels that are typically detected in the environment. The objective of this study was to estimate the selection potential of chlortetracycline (CTC) on the antibiotic resistance of aerobic bacterial populations in a simulated river water ecosystem. Six replicates of a 10-day experiment using river water in continuous flow chemostat systems were conducted. Each replicate used three chemostats, one serving as a control to which no antibiotic was added and the other two receiving low and high doses of CTC (8 μg/liter and 800 μg/liter, respectively). The addition of CTC to the chemostats did not impact the overall level of cultivable aerobic bacteria (
P
= 0.51). The high-CTC chemostat had significantly higher tetracycline-resistant bacterial colony counts than both the low-CTC and the control chemostats (
P
< 0.035). The differences in resistance between the low-CTC and control chemostats were highly nonsignificant (
P
= 0.779). In general a greater diversity of
tet
resistance genes was detected in the high-CTC chemostat and with a greater frequency than in the low-CTC and control chemostats. Low levels of CTC in this in vitro experiment did not select for increased levels of tetracycline resistance among cultivable aerobic bacteria. This finding should not be equated with the absence of environmental risk, however. Low concentrations of antibiotics in the environment may select for resistant bacterial populations once they are concentrated in sediments or other locations.
ThemutTDefect Does Not Elevate Chromosomal Fragmentation inEscherichia coliBecause of the Surprisingly Low Levels of MutM/MutY-Recognized DNA Modifications
Authors: Rotman Ella , Kuzminov Andrei 
Published: July 2007

ABSTRACTNucleotide pool sanitizing enzymes Dut (dUTPase), RdgB (dITPase), and MutT (8-oxo-dGTPase) ofEscherichia colihydrolyze noncanonical DNA precursors to prevent incorporation of base analogs into DNA. Previous studies reported dramatic AT→CG mutagenesis inmutTmutants, suggesting a considerable density of 8-oxo-G in DNA that should cause frequent excision and chromosomal fragmentation, irreparable in the absence of RecBCD-catalyzed repair and similar to the lethality ofdut recBCandrdgB recBCdouble mutants. In contrast, we foundmutT recBCdouble mutants viable with no signs of chromosomal fragmentation. Overproduction of the MutM and MutY DNA glycosylases, both acting on DNA containing 8-oxo-G, still yields no lethality inmutT recBCdouble mutants. Plasmid DNA, extracted frommutT mutMdouble mutant cells and treated with MutM in vitro, shows no increased relaxation, indicating no additional 8-oxo-G modifications. Our ΔmutTallele elevates the AT→CG transversion rate 27,000-fold, consistent with published reports. However, the rate of AT→CG transversions in ourmutT+progenitor strain is some two orders of magnitude lower than in previous studies, which lowers the absolute rate of mutagenesis in ΔmutTderivatives, translating into less than four 8-oxo-G modifications per genome equivalent, which is too low to cause the expected effects. Introduction of various additional mutations in the ΔmutTstrain or treatment with oxidative agents failed to increase the mutagenesis even twofold. We conclude that, in contrast to the previous studies, there is not enough 8-oxo-G in the DNA ofmutTmutants to cause elevated excision repair that would trigger chromosomal fragmentation.
RegA Control of Bacteriochlorophyll and Carotenoid Synthesis in
Rhodobacter capsulatus
Authors: Willett Jonathan , Smart James L. , Bauer Carl E. 
Published: July 2007

ABSTRACT

We provide in vivo genetic and in vitro biochemical evidence that RegA directly regulates bacteriochlorophyll and carotenoid biosynthesis in
Rhodobacter capsulatus
. β-Galactosidase expression assays with a RegA-disrupted strain containing reporter plasmids for Mg-protoporphyrin IX monomethyl ester oxidative cyclase (
bchE
), Mg-protoporphyrin IX chelatase (
bchD
), and phytoene dehydrogenase (
crtI
) demonstrate RegA is responsible for fourfold anaerobic induction of
bchE
, threefold induction of
bchD
, and twofold induction of
crtI
. Promoter mapping studies, coupled with DNase I protection assays, map the region of RegA binding to three sites in the
bchE
promoter region. Similar studies at the
crtA
and
crtI
promoters indicate that RegA binds to a single region equidistant from these divergent promoters. These results demonstrate that RegA is directly responsible for anaerobic induction of bacteriochlorophyll biosynthesis genes
bchE
,
bchD
,
bchJ
,
bchI
,
bchG
, and
bchP
and carotenoid biosynthesis genes
crtI
,
crtB
, and
crtA
.
Synthesis and Characterization of Chromium‐Doped Mesoporous Tungsten Oxide for Gas Sensing Applications
Authors: Rossinyol E. , Prim A. , Pellicer E. , Arbiol J. , Hernández‐Ramírez F. , Peiró F. , Cornet A. , Morante J. R. , Solovyov L. A. , Tian B. , Bo T. , Zhao D. 
Published: June 2007

AbstractSBA‐15 (2D hexagonal structure) and KIT‐6 (3D cubic structure) silica materials are used as templates for the synthesis of two different crystalline mesoporous WO3 replicas usable as NO2 gas sensors. High‐resolution transmission electron microscopy (HRTEM) studies reveal that single‐crystal hexagonal rings set up the atomic morphology of the WO3 KIT‐6 replica, whereas the SBA‐15 replica is composed of randomly oriented nanoparticles. A model capable of explaining the KIT‐6 replica mesostructure is described. A small amount of chromium is added to the WO3 matrix in order to enhance sensor response. It is demonstrated that chromium does not form clusters, but well‐distributed centers. Pure WO3 KIT‐6 replica displays a higher response rate as well as a lower response time to NO2 gas than the SBA‐15 replica. This behavior is explained by taking into account that the KIT‐6 replica has a higher surface area as demonstrated by Brunauer–Emmett–Teller analyses and its mesostructure is fully maintained after the screen‐printing step involved in sensors preparation. The presence of chromium in the material results in a shorter response time and improved sensor response to the lowest NO2 concentrations tested. Electrical differences related to mesostructure are reduced as a result of additive introduction.
Towards a Fundamental Understanding of the Improved Electrochemical Performance of Silicon–Carbon Composites
Authors: Saint J. , Morcrette M. , Larcher D. , Laffont L. , Beattie S. , Pérès J.‐P. , Talaga D. , Couzi M. , Tarascon J.‐M. 
Published: June 2007

AbstractSilicon–carbon composites consisting of Si particles embedded in a dense and non‐porous carbon matrix are prepared by the pyrolysis of intimate mixtures of poly(vinyl chloride) (PVC) and Si powder at 900 °C under a flow of N2. In contrast to bare micrometer‐sized (1–10 μm) and nanometer‐sized (10–100 nm) Si powders, which show poor cycling behavior with almost no capacity remaining after 15 cycles, the texture of the composite is seen to greatly enhance the reversibility of the alloying reaction of Si with Li. For instance, a capacity of ca. 1000 mA h g–1 is achieved for 20 cycles (0–2.0 V vs. Li+/Li) for a silicon–carbon composite containing nanometer‐sized Si particles. We also demonstrate that a mild manual grinding treatment degrades the cycling performance of the composites to levels as low as the parent Si, even though free Si is not released. The electrochemical measurements in conjunction with Raman spectroscopy data indicate that a huge stress is exerted on the Si domains by the in situ formed carbon. This carbon‐induced stress is found to disappear during the milling of the composites, indicating that the carbon‐induced pressure, along with the accompanying improvement in electrical connectivity, are the key parameters for the improved cycling behavior of Si versus Li.
Surface Imprinting in Layer‐by‐Layer Nanostructured Films
Authors: Shi F. , Liu Z. , Wu G.‐L. , Zhang M. , Chen H. , Wang Z. Q. , Zhang X. , Willner I. 
Published: June 2007

AbstractIn this Full Paper, we develop a novel approach for the generation of stable molecularly imprinted sites in polymeric films by combining the layer‐by‐layer (LbL) technique and photochemical crosslinking of the layered structure. After photo‐crosslinking, the imprinted films show high reproducibility and rapid loading and unloading of imprinted sites by the template molecules. Moreover, the competitive adsorption of template molecules and redox labels into the imprinted film using electrochemical methods indicates that the imprinted film has higher affinity for template molecules. We believe this approach may have some advantages over traditional ways of preparing imprinted sites in polymer matrices and it may open a new avenue for the functionalization of LbL films.
Column configurations of continuous heterogeneous extractive distillation
Authors: Rodriguez‐Donis Ivonne , Papp Katalin , Rev Endre , Lelkes Zoltan , Gerbaud Vincent , Joulia Xavier 
Published: June 2007

AbstractIncreasing regulations and constraints have renewed interest for more efficient distillation process in separating azeotropic mixtures and close boiling components. We investigate the feasibility of heterogeneous extractive distillation process in a continuous column considering several feed point strategies for the entrainer recycle stream and for the main azeotropic feed. Depending on these choices, the heterogeneous distillation column is composed of one, two, or three column sections. A differential mass balance model enables to compute continuous liquid composition profiles of the rectifying, extractive, and stripping sections. Unlike homogeneous extractive distillation, reflux policy composed by a single or both decanted liquid phases is considered as well as the external feeding influence on the composition of the top column liquid stream. Limiting operating conditions of key parameters like the entrainer/feed flowrate ratio and reflux ratio required to obtain a target top and bottom product compositions are obtained. For illustration, separation of acetonitrile–water mixture using butyl acetate as a heavy heterogeneous entrainer is selected. In this case, withdrawal of a saddle binary heteroazeotrope is the main difference of this process compared with the well‐known heterogeneous azeotropic distillation process where the top vapor product is the lower boiling point of the ternary system. © 2007 American Institute of Chemical Engineers AIChE J, 2007
An alternative approach to the modification of talc for the fabrication of polypropylene/talc composites
Authors: Wang Tao , Liu Dan , Keddie Joseph L. 
Published: June 2007

AbstractWe report an alternative method to modify talc for use in the fabrication of composites of polypropylene (PP) and talc. Grinding pulverization is employed to prepare talc fillers (referred to hereafter as p‐talc). The properties of composites made with p‐talc compare favorably with composites made with pulverized talc that has been further treated with a silane coupling agent (referred to as s‐talc). The morphology of PP/p‐talc composites illustrates particle orientation and a uniform dispersion of pulverized talc in the PP matrix. Modulated DSC analysis shows the ability of p‐talc and s‐talc to nucleate PP crystallization. The mechanical properties (i.e., the dynamic modulus, tensile strength, and impact resistance) of the PP/p‐talc composites are very similar to PP/s‐talc composites. The modification of talc by grinding is thus a highly effective alternative method to prepare PP/talc composites that does not require chemical treatment of the talc. The pulverization method is simpler and less expensive in comparison to silane treatment. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007