bluuebunny/crossref_metadata_2025_split huggingface dataset:
Predation of Apochthonius minimus (Pseudoscorpionida: Chthoniidae) on Folsomia Candida (Collembola: Isotomidae) II. Effects of predation on prey populations
Authors: Johnson Dan L. , Wellington W. G. 
Published: December 2006

SummaryThis study utilized the preference the pseudoscorpion, A. minimus, displays for certain sizes of the springtail, F. candida, in order to assess the population consequences of this selective predation. Although predation drove half of the treated collembolan populations to extinction, the populations which survived were not reduced in size and were in fact larger than most of the control populations (Figs. 1 and 2). During the first two weeks of the experiment, the predators apparently fed mainly on the original adults and the larger individuals of the second generation, thus increasing available space and improving the prey's chances for successful reproduction. The resulting demographic shift accounts for the significant decrease in mean length that occurred in the experimental populations without any accompanying significant change in their total numbers. Some effects of density, food, and age‐structure on the fecundity of F. candida, acting in concert with the effects of size‐selective predation, may lead to a variety of population consequences. In some circumstances, predation may cause increased production with decreased mean size, and no drastic change in standing crop. In different circumstances, a local population may become extinct. These results should further our understanding of the sporadic record of establishment and growth displayed byspringtail populations in the small, moist litter patches where they tend to aggregate.
The effect of population density on the reproduction of Trichogramma japonicum Ashmead (Hymenoptera: Trichogrammatidae)
Authors: Kuno Eizi 
Published: December 2006

SummaryWhen a fixed number of the hosts, the eggs of the almond moth were exposed experimentally to various numbers of the parasites, Trichogramma japonicum, the following changes were observed with increasing parasite density:
The percentage of parasitism rises and approaches to 100 with gradually diminishing rate.
The number of parasite progeny increases and reaches a maximum, then decreases gradually.
The number of eggs laid per parasite female decreases gradually.
The proportion of hyperparasitized hosts progressively rises. The frequency distribution of parasite eggs in a host is of an intermediate type between random and uniform.
The competition among parasite larvae becomes severe. The progressive rise in mortality, the declining percentage of females in progeny and the emergence of stunted adults at the higher densities are observed.
In connection with both the nature of the parasitizing behaviour of adult and that of the competition among larvae, the nature of the density effect on the parasite population was discussed.
Reproductive properties of two sympatric dung beetles, Aphodius haroldianus and A. Elegans (Coleoptera: Scarabaeidae)
Authors: Yasuda Hironori 
Published: December 2006

Summary
Reproductive properties of two sympatric dung beetles, Aphodius haroldianus and A. elegans, were studied at a pasture in the central Japan.
Overwintered adults of A. haroldianus came flying to dung pats from May to early August and bred from June to July. A. elegans overwintered as larvae, new adults came to dung pats from mid May to mid June. After aestivation, they reproduced from October to November.
A. haroldianus was a species with low fecundity and large food reserve for larvae. Female of this species had short duration of residence and laid fewer number of eggs in one dung pat. On the other hand, A. elegans was a species with high fecundity and small food reserve for larvae. Female of this species had long duration of residence and laid larger number of eggs in one dung pat.
The daily egg production in A. haroldianus reached a peak (0.40 eggs/female/day) at middle of oviposition period, but, that in A. elegans reached a peak (6.49 eggs/female/ day) at the beginning of oviposition period. The mortality of A. haroldianus female occurred after the daily egg production reached a peak and then rapidly increased, whereas that of A. elegans began soon after the beginning of oviposition and then gradually increased.
An analysis of foundress group size in Ropalidia fasciata (Hymenoptera: Vespidae), with zero‐truncated distributions
Authors: Itô Yosiaki , Iwahashi Osamu 
Published: December 2006

SummaryDistribution patterns of foundress group size of Ropalidia fasciata did not fit to 0‐truncated Poisson series due to overdispersion. Six of seven distributions fitted to 0‐truncated negative binomial series, but, for most cases, neither Brass' moment method nor the maximum liklihood method could be used due to disproportionately high frequency of nests with single foundress. Existence of two kinds of foundresses was suggested.
A study on the community analysis using three‐factorial data (time x site x species)
Authors: Matsumiya Yoshiharu , Wada Keiko 
Published: December 2006

Summary
This study is to demonstrate that the analysis of biological communities using scaling unstandardized squared Euclidean distance is extremely effective to deal with data which are quite generally collected by 3 factors (time x site x species).
The main part of this study has been explained in detail byWilliams andStephenson (1973). We have conducted some discussion introducing mathematic complementary explanation as well as expansive interpretation.
The dissimilarity measure based on squared Euclidean distance is used to classify clusters from a dendrogram obtained by cluster analysis. The outline of the community structure can be known by comparing the values of mean variance per comparison and interaction.
The table of mutual comparison among clusters introduces dynamic pattern expression for community. Contributions by species to time and site are capable of expressing a concrete role of the species.
We apply the technique above to the demersal fish community in Shijiki Bay, Hirado Island, Nagasaki Pref. Number of individuals caught with Gochi trawls at 11 fixed stations in 1975–1984 are used as material for analysis. 84 species is accounted.
Seasonal changes in ovarian state in a eusocial halictine bee, Lasioglossum duplex, based on stages of the oldest oocytes in each ovariole (Hymenoptera: Halictidae)
Authors: Gôukon Katsuo , Maeta Yasuo , Sakagami Shôichi F. 
Published: December 2006

SummaryThe changes in ovarian activity in the life cycle of the eusocial halictine bee Lasioglossum (Evylaeus) duplex (Dalla Torre) was studied in both queens and workers by examining the stages of the terminal follicle in each of the six ovarioles. By this method, ovarian activities of both queens and workers were more quantitatively determined than by observation of gross ovarian features as usually conducted. Queen ovaries clearly exhibited two active periods, corresponding to the spring solitary phase and the summer eusocial phase, with distinctly greater activity in the latter. In ovaries of overwintering queens oosorption of young follicle was observed. Worker ovaries were found more active in orphan than in queenright colonies. The order of ovarian activity obtained from pooled data, summer queens>spring queens>orphan workers>queenright workers, was also recognized by comparison of individual females.
Modeling the nucleation and crystallization kinetics of a palm stearin/canola oil blend and lard in bulk and emulsified form
Authors: Campbell Shawn D. , Douglas Goff H. , Rousseau Dérick 
Published: December 2006

AbstractUsing high‐pressure homogenization to generate different droplet size distributions, the nucleation and crystallization of two fat systems [lard or a plam stearin/canola oil blend (PSCO)] were compared in bulk and emulsified form. Droplet size reduction decreased the final volume fraction of solid fat primarily in the lard system vs. the PSCO system, with a greater reduction in volume fraction using the homogenization regime that led to smaller droplets. Homogeneous and heterogeneous models showed that the nucleation rate generally decreased with a reduction in droplet size. However, the Gibbs surface energy (γ) was significantly underestimated using the homogeneous model, whereas the heterogeneous model fit the data adequately (P<0.05). The temperature sensitivity of the calculated impurity concentration in all emulsified systems was droplet size dependent. The Avrami model showed the emulsified fats to have lower Avrami indices relative to the bulk fat as well as lower crystallization rate constants. Differences in the Avrami indices and the rate constants were more pronounced in the bulk and emulsified PSCO compared with lard.
Seed oil fatty acids of loasaceae—A new source of γ‐linolenic and stearidonic acids
Authors: Aitzetmüller K. , Brühl L. , Weigend M. 
Published: December 2006

AbstractThe pharmaceutically interesting Δ6‐FA 18∶3Δ6c, 9c, 12c (γ‐linolenic acid) and 18∶4Δ6c,9c,12c,15c (stearidonic acid) appear to have evolved independently several times during plant phylogenetic evolution. They typically occur in “clusters” of a few closely related species or genera in about a dozen different plant families throughout the plant kingdom. A hither‐unknown “cluster of occurrence” has now been discovered in the New World plant family Loasaceae. γ‐Linolenic and stearidonic acids occur exclusively in representatives of the newly described genus Nasa at significance levels of between 3 and 10% each. Nasa had recently been separated from the older, more broadly circumscribed genus Loasa. The two Δ6‐FA were not found in the closely related genus Loasa sensu stricto, nor in a number of other representatives of Loasaceae.
Simulation of batch physical refining and deodorization processes
Authors: Ceriani Roberta , Meirelles Antonio J. A. 
Published: December 2006

AbstractThis work presents an application of a differential distillation model for the simulation of batch physical refining and/or deodorization processes in the vegetable oil industry. The vapor‐liquid equilibria of these fat systems are described by group contribution equations for vapor pressures and activity coefficients published elsewhere, (Ceriani, R., and A.J.A. Meirelles, Predicting Vapor‐Liquid Equilibria of Fatty Systems, Fluid Phase Equilib. 215:227–236, 2004; Fredenslund, A., J. Gmehling, and P. Rasmussen, Vapor‐Liquid Equilibria Using UNIFAC, Elsevier Scientific, Amsterdam, 1977). The full complexity of the oil, expressed as its total composition of TAG, DAG, MAG, and FFA, is considered within the simulation. This approach permitted us to quantify and quality distillative neutral oil losses during physical refining. Three different models of differential distillation were tested to develop a good representation of the batch process to be applied to the physical refining and/or deodorization of complex mixtures such as vegetable oils. To evaluate the recommended approach, a case study was performed, namely, a batch deodorizer was simulated for coconut oil refining, and the results were compared with those reported in the literature.
Physical Properties of Polyurethanes Produced from Polyols from Seed Oils: I. Elastomers
Authors: Narine Suresh S. , Kong Xiaohua , Bouzidi Laziz , Sporns Peter 
Published: December 2006

AbstractPolyols synthesized by ozonolysis and hydrogenation from canola oil were reacted with aliphatic 1,6‐hexamethylene diisocyanates (HDI) to produce polyurethane (PU) elastomers. The properties of the materials were examined by dynamic mechanical analysis (DMA), thermomechanical analysis (TMA), modulated differential scanning calorimetry (MDSC), and thermogravimetric analysis (TGA), and measurements were taken of tensile properties. The effect of dangling chains on network properties was assessed. The formation of hydrogen bonds was observed by FTIR. The measured properties were found to be strongly dependent on processing‐dependent factors such as the crosslinking density and the molar ratio of polyols to HDI component. The glass transition temperatures (Tg) of the elastomers were found to increase as the OH/NCO molar ratio decreased. With the same OH/NCO molar ratio, Tg of canola‐oil‐based PU was higher than that of soybean‐oil‐based PU. The TGA thermographs showed two well‐defined steps of degradation for all the elastomers. In the first step, up to 30% weight loss, the fastest rate of loss was found at 345 °C for canola‐oil‐based PU while soybean‐oil‐based PU lost most of the weight in the second step. With the same OH/NCO molar ratio, the elastomers made from canola‐oil‐based polyol showed slightly higher Young's modulus and tensile strength.
Polymeric Linoleic Acid–Polyolefin Conjugates: Cell Adhesion and Biocompatibility
Authors: Çakmaklı Birten , Hazer Baki , Tekin İshak Özel , Açıkgöz Şerefden , Can Murat 
Published: December 2006

AbstractTo diversify edible‐oil polymer composite, polymeric linoleic acid (PLina) peroxide was obtained by the auto‐oxidation of linoleic acid in a simple way for use as a macroinitiator in free radical polymerization of vinyl monomers. Peroxidation, epoxidation, and/or perepoxidation reactions of linoleic acid under air at room temperature resulted in PLina, having soluble fraction more than 91 weight percent (wt%), with molecular weight ranging from 1,644 to 2,763 Da, and containing up to 1.0 wt% of peroxide. PLina initiated the free radical polymerization of ether styrene (S), methyl methacrylate (MMA), or n‐butyl methacrylate (nBMA) to give PLina‐g‐polystyrene (PS), PLina‐g‐poly‐MMA (PMMA), and PLina‐g‐poly‐ nBMA (PnBMA) graft copolymers. The polymers obtained were characterized by proton nuclear magnetic resonance (1H NMR), thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), and gel permeation chromatography (GPC) techniques. Microstructure of the graft copolymers was observed by using scanning electron microscope (SEM). Graft copolymers obtained contained polymeric linoleic acid in a range between 8.5 and 19.3 mol percent (mol%). PLina‐g‐PS, PLina‐g‐PMMA and PLina‐g‐PnBMA graft copolymer samples were also used in cell culture studies. Fibroblast and macrophage cells were strongly adhered and spread on the copolymer film surfaces. These newly synthesized copolymers were tested for their effects on human blood protein adsorption compared with PMMA graft copolymers containing polymeric soybean oil and polymeric linseed oil; interestingly we observed a dramatic decrease in the protein adsorption on the linoleic acid graft copolymer, which is important in tissue engineering.
Electoral Systems, District Magnitude and Corruption
Authors: CHANG ERIC C. C. , GOLDEN MIRIAM A. 
Published: December 2006

The relationship between electoral systems and corruption in a large sample of contemporary democratic nations is analysed in this article. Whereas previous studies have shown that closed-list proportional representation is associated with greater (perceived) corruption than open-list PR, it is demonstrated here that this relationship fails to hold once district magnitude is considered. The theory underlying this study draws on work on ‘the personal vote’ that suggests that the incentives to amass resources – and perhaps even to do so illegally – increase with district magnitude in open-list settings but decrease in closed-list contexts. Extending this insight, it is shown that political corruption gets more (less) severe as district magnitude increases under open-list PR (closed-list PR) systems. In addition, once district magnitude exceeds a certain threshold – the estimates here are that this is as low as fifteen – corruption is greater under open lists than closed lists. Only at small district magnitudes (below fifteen) is closed-list PR associated with more corruption, as conventionally held. These results hold for alternative measures of corruption, for different sets of countries analysed, for different measures of district magnitude and regardless of whether the political system is presidential or parliamentary, and of the number of parties.Using an objective measure of corruption in public works contracting, corroborating evidence is also presented from Italian electoral districts. In Italy's open-list environment in the period prior to 1994, larger districts were more susceptible to corruption than smaller ones.
The Spn4 gene from Drosophila melanogaster is a multipurpose defence tool directed against proteases from three different peptidase families
Authors: Brüning Mareke , Lummer Martina , Bentele Caterina , Smolenaars Marcel M. W. , Rodenburg Kees W. , Ragg Hermann 
Published: December 2006

By alternative use of four RSL (reactive site loop) coding exon cassettes, the serpin (serine protease inhibitor) gene Spn4 from Drosophila melanogaster was proposed to enable the synthesis of multiple protease inhibitor isoforms, one of which has been shown to be a potent inhibitor of human furin. Here, we have investigated the inhibitory spectrum of all Spn4 RSL variants. The analyses indicate that the Spn4 gene encodes inhibitors that may inhibit serine proteases of the subtilase family (S8), the chymotrypsin family (S1), and the papain-like cysteine protease family (C1), most of them at high rates. Thus a cohort of different protease inhibitors is generated simply by grafting enzyme-adapted RSL sequences on to a single serpin scaffold, even though the target proteases contain different types and/or a varying order of catalytic residues and are descendents of different phylogenetic lineages. Since all of the Spn4 RSL isoforms are produced as intracellular residents and additionally as variants destined for export or associated with the secretory pathway, the Spn4 gene represents a versatile defence tool kit that may provide multiple antiproteolytic functions.
Differential involvement of thrombin receptors in Ca2+ release from two different intracellular stores in human platelets
Authors: Jardin Isaac , Ben Amor Nidhal , Bartegi Ahgleb , Pariente José A. , Salido Ginés M. , Rosado Juan A. 
Published: December 2006

Physiological agonists increase cytosolic free Ca2+ concentration to regulate a number of cellular processes. The platelet thrombin receptors, PAR (protease-activated receptor) 1 PAR-4 and GPIb-IX-V (glycoprotein Ib-IX-V) have been described as potential contributors of thrombin-induced platelet aggregation. Platelets present two separate Ca2+ stores, the DTS (dense tubular system) and acidic organelles, differentiated by the distinct sensitivity of their respective SERCAs (sarcoplasmic/endoplasmic-reticulum Ca2+-ATPases) to TG (thapsigargin) and TBHQ [2,5-di-(tert-butyl)-1,4-hydroquinone]. However, the involvement of the thrombin receptors in Ca2+ release from each Ca2+ store remains unknown. Depletion of the DTS using ADP, which releases Ca2+ solely from the DTS, in combination with 10 nM TG, to selectively inhibit SERCA2 located on the DTS reduced Ca2+ release evoked by the PAR-1 agonist, SFLLRN, and the PAR-4 agonist, AYPGKF, by 80 and 50% respectively. Desensitization of PAR-1 and PAR-4 or pre-treatment with the PAR-1 and PAR-4 antagonists SCH 79797 and tcY-NH2 reduced Ca2+ mobilization induced by thrombin, and depletion of the DTS after desensitization or blockade of PAR-1 and PAR-4 had no significant effect on Ca2+ release stimulated by thrombin through the GPIb-IX-V receptor. Converse experiments showed that depletion of the acidic stores using TBHQ reduced Ca2+ release evoked by SFLLRN or AYPGKF, by 20 and 50% respectively, and abolished thrombin-stimulated Ca2+ release through the GPIb-IX-V receptor when PAR-1 and PAR-4 had been desensitized or blocked. Our results indicate that thrombin-induced activation of PAR-1 and PAR-4 evokes Ca2+ release from both Ca2+ stores, while activation of GPIb-IX-V by thrombin releases Ca2+ solely from the acidic compartments in human platelets.
Interactions between substrates and the haem-bound nitric oxide of ferric and ferrous bacterial nitric oxide synthases
Authors: Chartier François J. M. , Couture Manon 
Published: December 2006

We report here the resonance Raman spectra of the FeIII–NO and FeII–NO complexes of the bacterial NOSs (nitric oxide synthases) from Staphylococcus aureus and Bacillus subtilis. The haem–NO complexes of these bacterial NOSs displayed Fe–N–O frequencies similar to those of the mammalian NOSs, in presence and absence of L-arginine, indicating that haem-bound NO and L-arginine had similar haem environments in bacterial and mammalian NOSs. The only notable difference between the two types of NOS was the lack of change in Fe–N–O frequencies of the FeIII–NO complexes upon (6R) 5,6,7,8-tetrahydro-L-biopterin binding to bacterial NOSs. We report, for the first time, the characterization of NO complexes with NOHA (Nω-hydroxy-L-arginine), the substrate used in the second half of the catalytic cycle of NOSs. In the FeIII–NO complexes, both L-arginine and NOHA induced the Fe–N–O bending mode at nearly the same frequency as a result of a steric interaction between the substrates and the haem-bound NO. However, in the FeII–NO complexes, the Fe–N–O bending mode was not observed and the νFe−NO mode displayed a 5 cm−1 higher frequency in the complex with NOHA than in the complex with L-arginine as a result of direct interactions that probably involve hydrogen bonds. The different behaviour of the substrates in the FeII–NO complexes thus reveal that the interactions between haem-bound NO and the substrates are finely tuned by the geometry of the Fe-ligand structure and are relevant to the use of the FeII–NO complex as a model of the oxygenated complex of NOSs.
Binding of calcium ions and SNAP-25 to the hexa EF-hand protein secretagogin
Authors: Rogstam Annika , Linse Sara , Lindqvist Anders , James Peter , Wagner Ludwig , Berggård Tord 
Published: December 2006

Secretagogin is a hexa EF-hand protein, which has been identified as a novel potential tumour marker. In the present study, we show that secretagogin binds four Ca2+ ions (log K1=7.1±0.4, log K2=4.7±0.6, log K3=3.6±0.7 and log K4=4.6±0.6 in physiological salt buffers) with a [Ca2+]0.5 of approx. 25 μM. The tertiary structure of secretagogin changes significantly upon Ca2+ binding, but not upon Mg2+ binding, and the amount of exposed hydrophobic surface in secretagogin increases upon Ca2+ binding, but not upon Mg2+ binding. These properties suggest that secretagogin belongs to the ‘sensor’ family of Ca2+-binding proteins. However, in contrast with the prototypical Ca2+ sensor calmodulin, which interacts with a very large number of proteins, secretagogin is significantly less promiscuous. Only one secretagogin-interacting protein was reproducibly identified from insulinoma cell lysates and from bovine and mouse brain homogenates. This protein was identified as SNAP-25 (25 kDa synaptosome-associated protein), a protein involved in Ca2+-induced exocytosis in neurons and in neuroendocrine cells. Kd was determined to be 1.2×10−7 M in the presence of Ca2+ and 1.5×10−6 M in the absence of Ca2+. The comparatively low Ca2+ affinity for secretagogin and the fact that it undergoes Ca2+-induced conformational changes and interacts with SNAP-25 raise the possibility that secretagogin may link Ca2+ signalling to exocytotic processes.