bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of Drought Frequency and Other Reach Characteristics on Invertebrate Communities and Litter Breakdown in the Intermittent Mediterranean River Pula (Sardinia, Italy)
Authors: Sangiorgio Franca , Fonnesu Alessio , Mancinelli Giorgio 
Published: May 2007

AbstractBenthic invertebrate communities were sampled in spring and fall, and breakdown of reed litter was measured in winter, spring, summer and fall, at 23 sites in an intermittent Mediterranean river basin (Pula, Sardinia, Italy), and their variations were related to drought frequency and other reach characteristics (altitude, order, stream channel width and depth, vegetation cover, sediment type, organic content, and water quality). 78% of the sites were affected by drought events, mainly in summer and fall. Benthic taxonomic richness was higher and most taxa were more widely distributed in spring than in fall. Canonical correspondence analysis showed that measured environmental variables accounted for 72% of the variance in invertebrate community structure. Reed decay rates varied among seasons, and during the dry season among stream orders as well. Drought events slowed down breakdown and explained 44% of spatial variability in decay rates (Stepwise multiple regression analysis), an additional 8% being explained by water chemistry. Results suggest that drought events affect ecosystem functioning (litter breakdown) more than structure (invertebrate communities). (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Litter Decomposition of Scirpus maritimus L. in a Mediterranean Coastal Marsh: Importance of the Meiofauna during the Initial Phases of Detached Leaves Decomposition
Authors: Sanmartí Neus , Menéndez Margarita 
Published: May 2007

AbstractGrowth, senescence and decomposition rates of Scirpus maritimus were studied in a Mediterranean brackish wetland. Plant tussocks were tagged in March, 2002 and were totally dead by September, 2002. Decomposition rates were determined over 360 days using litter bag technique and mass loss, nutrient dynamics, fungal biomass, meiofauna and macroorganisms were determined. Decomposition rate of detached S. maritimus litter was 0.00196 (k, day–1) with a 54% of mass lost observed in 1 year. The pattern of mass loss was characterized by an initial phase of fast loss of organic matter with high density of meiofauna and a decrease of oxygen content, followed by two slower phases, with no significant losses from 50 to 180 days and with 21% of mass lost from 180 to 360 days. Nitrogen (N) and phosphorus (P) content of plant litter increased during decomposition process whereas atomic C:N and C:P ratios decreased, suggesting a nutrient immobilization on plant detritus. Fungal biomass measured as ergosterol content decreased after submersion of leaves, indicating that their importance in litter decomoposition decreases in submerged leaves during the first days of decomposition. An inverse relationship (r = –0.79, P < 0.005) was observed between ergosterol content and nematodes density on S. maritimus litter. Our results suggest that in Mediterranean brackish marshes, where large amounts of dead organic matter is accumulated over the sediment surface, decomposition process is greatly affected by extremely high temperatures in summer that, if water is available, accelerates microbial activity decreasing oxygen content thus slowing decomposition. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Leachates of Eucalyptus globulus in Intermittent Streams Affect Water Parameters and Invertebrates
Authors: Canhoto Cristina , Laranjeira Celia 
Published: May 2007

AbstractLow order streams running through Eucalyptus globulus plantations in Central Portugal are frequently reduced to isolated permanent or temporary summer pools with darkly stained water due to leaf leachates. Here we assess the toxicity of such leachates to the shredder Sericostoma vittatum. Leachates resulted in deoxygenated and more acid water, and increased its phenolic content and conductivity. S. vittatum exposed to high concentrations of leachates failed to grow and died within 30 days even in the presence of high quality food. Larvae in water with half the leachate concentration, consumed less leaf material, had lower growth rates, did not pupate and died within 100 days. Eucalypt leachates per se may affect the viability and ecology of macroinvertebrates in Portuguese streams. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Invertebrates Colonization on Native Tree Leaves in a Neotropical Stream (Brazil)
Authors: Moretti Marcelo S. , Gonçalves José Francisco , Ligeiro Raphael , Callisto Marcos 
Published: May 2007

AbstractWe evaluate the composition and structure of invertebrate assemblages during leaf breakdown of five native tree species (Myrcia guyanensis, Ocotea sp., Miconia chartacea, Protium brasiliense and Protium heptaphyllum) and a mixture of them in a headwater stream, Southeastern Brazil. Coarse mesh litter bags were used over a 120‐day period. P. heptaphyllum showed the slowest breakdown rate, while Myrcia showed the fastest. Total densities and biomass values of associated invertebrates were different among leaf types and incubation periods. The highest values of total abundance were found in P. heptaphyllum, while Ocotea sp. and Miconia were few colonized. Gathering‐collectors feeding group dominated all leaf types, followed by predators and shredders. Shredders were more abundant in Myrcia than in Miconia and the mixed pack. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Top‐Down Control of Reed Detritus Processing in a Lake Littoral Zone: Experimental Evidence of a Seasonal Compensation between Fish and Invertebrate Predation
Authors: Mancinelli Giorgio , Costantini Maria Letizia , Rossi Loreto 
Published: May 2007

AbstractWe investigated whether predatory fish exert a top‐down control on reed leaf packs processing in a lake littoral zone through a trophic cascade. Exclosure experiments were repeated in summer and winter, under high and low natural fish abundance, respectively.Fish exclusion effects on detritus processing and fungal conditioning were consistent with trophic cascade predictions only in summer. In winter, however, results indicated that a trophic cascade was induced by predatory invertebrates. In both seasons, variations in detritivores abundance generally supported a cascade scenario, whereas several taxon‐specific departures occurred during the experimental periods. We conclude suggesting that predators may continuously regulate leaf detritus processing in lake littoral zones, through a seasonal shift in the relative contribution of fish and invertebrate predation. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A tightly regulated and reversibly inducible siRNA expression system for conditional RNAi‐mediated gene silencing in mammalian cells
Authors: Wu Ren‐Huang , Cheng Tsung‐Lin , Lo San‐Ren , Hsu Hui‐Chun , Hung Chuan‐Fu , Teng Chiao‐Fang , Wu Ming‐Ping , Tsai Wen‐Hui , Chang Wen‐Tsan 
Published: May 2007

AbstractBackgroundRNA interference (RNAi) is a powerful and widely used gene silencing strategy for studying gene function in mammalian cells. Transient or constitutive expression of either small interfering RNA (siRNA) or short hairpin RNA (shRNA) results in temporal or persistent inhibition of gene expression, respectively. A tightly regulated and reversibly inducible RNAi‐mediated gene silencing approach could conditionally control gene expression in a temporal or spatial manner that provides an extremely useful tool for studying gene function involved in cell growth, survival and development.Material and methodsIn this study, we have developed a lactose analog isopropyl thiogalactose (IPTG)‐responsive lac repressor‐operator‐controlled RNA polymerase III (Pol III)‐dependent human RNase P RNA (H1) promoter‐driven inducible siRNA expression system. To demonstrate its tight regulation, efficient induction and reversible inhibition, we have used this system to conditionally control the expression of firefly luciferase and human tumor suppressor protein p53 in both transient transfection cells and established stable clones.ResultsThe results showed that this inducible siRNA expression system could efficiently induce conditional inhibition of these two genes in a dose‐ and time‐dependent manner by administration of the inducing agent IPTG as well as being fully reverted after withdrawal of IPTG. In particular, this system could conditionally inhibit the expression of both the genes in not only established stable clones but also transient transfection cells, which should greatly increase its usefulness and convenience.ConclusionsThe results presented in this study clearly indicate that this inducible siRNA expression system could efficiently, conditionally and reversibly inhibit gene expression with only very low or undetectable background silencing effects under non‐inducing condition. Thus, this inducible siRNA expression system provides an ideal genetic switcher allowing the inducible and reversible control of specific gene activity in mammalian cells. Copyright © 2007 John Wiley & Sons, Ltd.
Recognized sequence and conformation in design of linear peptides as a competitive inhibitor for HMG‐CoA reductase
Authors: Pak Valeriy V. , Koo Minseon , Yun Lyubov , Kwon Dae Young 
Published: May 2007

AbstractThis study is an attempt to develop a simple search method for lead peptide candidates, which include constrained structures in a recognized sequence, using the design of a competitive inhibitor for HMG‐CoA reductase (HMGR). A structure‐functional analysis of previously synthesized peptides proposes that a competitive inhibitory peptide can be designed by maintaining bioactive conformation in a recognized sequence. A conformational aspect of the structure‐based approach was applied to the peptide design. By analysis of the projections obtained through a principle component analysis (PCA) for short linear and cyclic peptides, a head‐to‐tail peptide cycle is considered as a model for its linear analogy. It is proposed that activities of the linear peptides based on an identical amino acid sequence, which are obtained from a less flexible peptide cycle, would be relatively higher than those obtained from more flexible cyclic peptides. The design criterion was formulated in terms of a ‘V’ parameter, reflecting a relative deviation of an individual peptide cycle from an average statistical peptide cycle based on all optimized structures of the cyclic peptides in set. Twelve peptide cycles were selected for the peptide library. Comparing the calculated ‘V’ parameters, two cyclic peptides (GLPTGG and GFPTGG) were selected as lead cycles from the library. Based on these sequences, six linear peptides obtained by breaking the cycle at different positions were selected as lead peptide candidates. The linear GFPTGG peptide, showing the highest inhibitory activity against HMGR, increases the inhibitory potency nearly tenfold. Kinetic analysis reveals that the GFPTGG peptide is a competitive inhibitor of HMG‐CoA with an equilibrium constant of inhibitor binding (Ki) of 6.4 ± 0.3 µM. Conformational data support a conformation of the designed peptides close to the bioactive conformation of the previously synthesized active peptides. Copyright © 2007 John Wiley & Sons, Ltd.
A new testing method for vital gluten swelling index
Authors: Hu XinZhong , Shang YaNing 
Published: May 2007

AbstractVital gluten is a kind of functional protein, but currently its quality indices are mostly focused on the outer character rather than the inner content. The objective of this study was to develop an improved testing method for the measurement of vital gluten, reported here as the vital gluten swelling index (VGSI). The procedures were optimized using the vital gluten water absorption ratio and the wheat flour protein fraction content. The following procedure is recommended: use 0.9 mL distilled water to hydrate 20 mg vital gluten for 10 min, and then add 0.9 mL of 0.03 g kg−1 sodium dodecyl sulfate–lactic acid solution and mix for another 30 min. Finally, centrifuge the mixture at 5000 × g and measure the residue weight. The quality of vital gluten can be simply classified by its swelling index value. A VGSI of ≥ 28% indicates vital gluten of superior grade, between 24% and 28% is a good grade, while ≤24% is an inferior grade. Compared with the laborious method of vital gluten water absorption (VGWA), which takes a relatively long time to test one sample, VGSI requires only 47 min to test 24 samples. Further, the VGSI method is more accurate, reliable and repeatable. The coefficient of variation of VGWA of the vital gluten samples is 2.09, while the corresponding value for VGSI was 14.83. The correlation coefficients between VGSI and other vital gluten indices were significant. The research indicates that the method developed is the best to evaluate vital gluten. Copyright © 2007 Society of Chemical Industry
The impact of cold temperatures during grain maturation on selected quality parameters of wheat
Authors: Craven Maryke , Barnard Annelie , Labuschagne Maryke T 
Published: May 2007

AbstractThe influence of sudden cold spells during grain filling of wheat on the quality traits of three South African hard red wheat cultivars (Gariep, Elands and Tugela‐DN) was studied, with the emphasis on Hagberg falling number (HFN). Four treatments were used (−1 °C at soft dough stage, − 1 °C at late milk stage, − 4 °C at soft dough stage and − 4 °C at late milk stage) and were administered for one night only. From the results it was concluded that, although limited in duration, such frost conditions did have an effect on the quality of the wheat cultivars. Cultivars differed in their response to the various treatments but also as to what quality traits were affected the most. The − 4 °C at late milk stage resulted in significantly reduced HFN being measured for both Elands and Tugela‐DN. A similar effect was observed for Gariep, but was not statistically significant. Although the response was limited to the main tillers only, the conclusion was made that it is probable that the reduced HFN would be visible in the pooled sample of head and side tillers. A screening protocol was suggested that would allow classification of cultivars for frost tolerance. Copyright © 2007 Society of Chemical Industry
On a semilinear elliptic equation with singular term and Hardy–Sobolev critical growth
Authors: Chen Jianqing 
Published: May 2007

AbstractIn a previous work [6], we got an exact local behavior to the positive solutions of an elliptic equation. With the help of this exact local behavior, we obtain in this paper the existence of solutions of an equation with Hardy–Sobolev critical growth and singular term by using variational methods. The result obtained here, even in a particular case, relates with a partial (positive) answer to an open problem proposed in: A. Ferrero and F. Gazzola, Existence of solutions for singular critical growth semilinear elliptic equations, J. Differential Equations 177, 494–522 (2001). (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On the decay of the solutions of second order parabolic equations with Dirichlet conditions
Authors: Franke Brice 
Published: May 2007

AbstractWe use rearrangement techniques to investigate the decay of the parabolic Dirichlet problem in a bounded domain. The coefficients of the second order term are used to introduce an isoperimetric problem. The resulting isoperimetric function together with the divergence of the first order coefficients and the value distribution of the zero order part are then used to construct a symmetric comparison equation having a slower heat‐flow than the original equation. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Régularisation et $ \bar \partial_b $ homotopie sur les variétés CR
Authors: Sambou Salomon 
Published: May 2007

AbstractOn donne un résultat de régularisation et $ \bar \partial_b $‐homotopie sur les variétés CR génériques. On en déduit des théorèmes d'isomorphisme entre groupes de $ \bar \partial_b $ cohomologie.Ce résultat généralise un travail de Chirka obtenu sur les variétés complexes. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A multifractal decomposition according to rate of returns
Authors: Ma Jihua , Wen Zhiying 
Published: May 2007

AbstractFor one‐dimensional simple symmetric random walk, the Hausdorff and packing dimensions of sets of sample paths with prescribed rate of returns to the origin are determined. This gives a multifractal decomposition of the underlying sample space. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Resolvent estimates in W−1,p related to strongly coupled‐linear parabolic systems with coupled nonsmooth capacities
Authors: Glitzky Annegret , Hünlich Rolf 
Published: May 2007

AbstractWe investigate linear parabolic systems with coupled nonsmooth capacities and mixed boundary conditions. We prove generalized resolvent estimates in W−1, p spaces. The method is an appropriate modification of a technique introduced by Agmon to obtain Lp estimates for resolvents of elliptic differential operators in the case of smooth boundary conditions. Moreover, we establish an existence and uniqueness result. Copyright © 2007 John Wiley & Sons, Ltd.
Post‐spike excitability indicates changes in membrane potential of isolated C‐fibers
Authors: Moalem‐Taylor Gila , Lang Philip M. , Tracey David J. , Grafe Peter 
Published: May 2007

AbstractRecording of action potentials from single unmyelinated nerve fibers by microneurography is an important tool to investigate peripheral neural functions in human neuropathies. However, the interpretation of microneurography recordings can be difficult because axonal membrane potential is not revealed by this method. We tested the hypothesis that the recovery cycle of excitability after a single action potential is correlated with changes in the axonal membrane potential. To this end, we used the threshold tracking technique to study how different chemical mediators, with known effects on the membrane potential, influence the post‐spike superexcitability of C‐fiber compound action potentials in isolated rat sural and vagus nerves. We found that: (1) some chemical mediators (e.g., adenosine 5′‐triphosphate) produce a reduction or loss of superexcitability together with increased axonal excitability, indicating membrane depolarization; (2) blockade of axonal hyperpolarization‐activated (Ih) currents produces an enhancement of superexcitability together with a decreased excitability, indicating membrane hyperpolarization; and (3) application of calcium produces an increase in membrane threshold without an alteration in superexcitability, indicating a non‐specific increase in surface charge and a change in the voltage‐dependent activation of sodium channels. In addition, we demonstrated that membrane depolarization and hyperpolarization induce opposite post‐spike latency shifts (changes in supernormality) in rat and human nerve segments. Thus, recordings of post‐spike excitability and shifts in latency are sensitive techniques for detection of various types of neuromodulation, which are correlated with changes in membrane potential of unmyelinated peripheral axons and may help to understand observations obtained by microneurography in peripheral human neuropathies. Muscle Nerve, 2007
Altered mRNA splicing of dystrophin in type 1 myotonic dystrophy
Authors: Nakamori Masayuki , Kimura Takashi , Fujimura Harutoshi , Takahashi Masanori P. , Sakoda Saburo 
Published: May 2007

AbstractMyotonic dystrophy type1 (DM1) is a multisystemic disorder caused by a CTG repeat expansion in the DMPK gene. Aberrant mRNA splicing of several genes has been reported to contribute to some of the symptoms, including myotonia and insulin resistance, but the cause of muscle wasting is unknown. Dystrophin is a cytoskeletal protein that is required for structural stability and signaling at the sarcolemma and has several spliced isoforms. We investigated the alternative splicing of dystrophin in skeletal and cardiac muscle of DM1 patients by using reverse transcriptase–polymerase chain reaction and found that dystrophin isoforms lacking exon 71 or 78, which is suggested to encode an important region for protein binding and hydrophobicity, were significantly increased. We suggest that the aberrantly spliced dystrophin is responsible for the muscle wasting in DM1. Muscle Nerve, 2007
Late‐onset monomelic amyotrophy in a Caucasian woman
Authors: Patel Dharmesh R. , Knepper Laurie , Jones H. Royden 
Published: May 2007

AbstractWe describe a 53‐year‐old Caucasian woman with a 19‐year history of an evolving amyotrophy confined to her dominant right arm and hand. Although this atypical case of a late‐onset monomelic amyotrophy in some respects mimics Hirayama disease or O'Sullivan–McLeod syndrome, it does not conform precisely with either of those disorders. We compare this individual's difficulties and clinical temporal profile to other disorders considered in the differential diagnoses with regard to her evolving clinical setting. Muscle Nerve, 2007
Urodynamic and ultrasound characteristics of incontinence after radical hysterectomy
Authors: Axelsen Susanne Maigaard , Bek Karl Moeller , Petersen Lone Kjeld 
Published: May 2007

AbstractAimsTo test whether symptoms of urinary incontinence after radical hysterectomy could be objectified with urodynamics and ultrasound.MethodsThis case‐control study comprised 100 women who underwent radical hysterectomy for cervical cancer without post‐operative radiotherapy. Fifty women reporting urinary incontinence were matched with 50 women reporting continence. All women were assessed with ultrasound of the bladder neck movements and urodynamics.ResultsNo differences were found in ultrasound or urodynamic findings regarding mobility of the bladder neck, maximal detrusor pressure, post‐voiding residual urine, flow of urine, or bladder capacity. A significant reduction in urethral pressure at rest and at contraction among the incontinent women was, however, demonstrated. Among urge‐incontinent women, urethral pressure at rest was significantly lower than among continent and stress‐incontinent women, respectively. Stress‐incontinent women had significantly lower urethral pressure at contraction than did urge‐incontinent and continent women.ConclusionsNo differences in urodynamic or ultrasound findings were observed between the two groups, except for an overall difference in the intraurethral pressure. A decrease in the urethral pressure could contribute to the characterization of incontinence after radical hysterectomy, indicating that the urethral sphincter mechanism plays a role in the pathophysiology. In this study design, the mobility of the bladder neck did not play any role. Neurourol. Urodynam. 26:794–799, 2007. © 2007 Wiley‐Liss, Inc.