bluuebunny/crossref_metadata_2025_split huggingface dataset:
Geographical variation in calling song of the field cricket Teleogryllus oceanicus: the importance of spatial scale
Authors: Zuk M. , Rotenberry J. T. , Simmons L. W. 
Published: March 2003

Abstract
We compared calling songs of the field cricket Teleogryllus oceanicus from 15 sites within six regions of two continental areas, Oceania and Australia. The cricket was introduced to Hawaii, where it is subject to an acoustically orienting parasitoid fly not found elsewhere in its range. In a principal components analysis (PCA) of song from all populations combined, the first five components had eigenvalues greater than one, and collectively accounted for over 80% of the total variation. Means for all song components varied significantly among sites, and different components varied at the three levels of analysis (continent, region and site). The principal way in which sites differed was along a gradient in increasing song length, pulse duration and intervals between song elements. Crickets from Oceania had a significantly greater variance in their song than Australian crickets, driven largely by the high variance in Hawaii. Geography explained a substantial amount of variation in song, despite the likelihood of serial bottlenecks having occurred as the species moved from island to island. Because female crickets appear not to focus on the short chirp as a component of mate choice, a lack of selection may allow this song component to vary more widely.
Genetic and environmental factors affecting reproductive variation in Allium vineale
Authors: Ceplitis A. 
Published: March 2003

Abstract
Traits related to allocation of resources to sexual and asexual reproduction, together with seed production, were scored on Allium vineale plants sampled from five sites in southern Sweden during a period of 4 years. In addition, random amplified polymorphic DNA (RAPD) fingerprinting of the sampled plants allowed the identification of genets. Integration of genetic and phenotypic data from field and greenhouse provided for the analysis of among-year, among-site, and among-genet variance components. These variance components were taken to represent the influences of short-term environmental changes, persistent site divergence, and within-site genet differences, respectively.
It was shown that differences among sites and among genets explained a large part of the phenotypic variation of allocation traits, whereas among-year differences had a larger influence on the variation in seed production. Together, the results support the conclusions of a recent model on the evolution of mixed reproductive systems, that predicts a stable balance between sexual and asexual reproduction because of annual fluctuations in fecundity through the two modes.
Potential genetic benefits of mate selection in whitefish
Authors: Wedekind C. , Müller R. , Spicher H. 
Published: March 2003

Abstract
To test the potential of optimal mate selection with respect to offspring viability, we crossed 10 female and 10 male whitefish in all possible combinations and reared the resulting 100 sib groups in several replicates. We recorded two types of egg mortality, one that was correlated to developmental problems, and a later one that was correlated to a bacterial infection. We found strong maternal and paternal effects in both types of mortality. Early mortality also depended on which female was mated with which male, suggesting partial incompatibilities. The later mortality, but not the former, could be predicted by male breeding ornamentation. More strongly ornamented males sired offspring that better survived the epidemic during egg development. This ‘good genes’ effect was larger than expected from theory: optimal mate selection would have improved offspring survival during the epidemic by about 12% (or reduce mortality by about 66%) as compared with random mating.
Social situation, sperm competition and sex allocation in a simultaneous hermaphrodite parasite, the cestode Schistocephalus solidus
Authors: Schärer L. , Wedekind C. 
Published: March 2003

Abstract
Evolutionary theory predicts an influence of mating group size on sex allocation in simultaneous hermaphrodites. We experimentally manipulated the social situation during reproduction in a simultaneous hermaphrodite parasite, the tapeworm Schistocephalus solidus, by placing worms as singles, pairs or triplets into an in vitro system that replaces the final host. We then determined the reproductive allocation patterns after 24 h (i.e. before the start of egg release) and after 72 h (i.e. around the peak of egg release rate) using stereology. After 24 h, sex allocation strongly depended on worm volume (which is determined in the second intermediate host), but was not significantly affected by the social situation experienced during reproduction. After 72 h, worms in groups had less vesicular sperm (i.e. sperm to be used in future inseminations) than singles. They also stored significantly more received sperm in their seminal receptacles than singles, suggesting that more sperm had been transferred in groups. Moreover, worms in triplets stored significantly more received sperm than worms in pairs, suggesting that they either mated more often and/or transferred more sperm per mating. This suggests a behavioural response to the increased risk of sperm competition in triplets. We further discuss the relative importance of sex allocation decisions at different life-history stages.
Competitiveness and life-history characteristics of Daphnia with respect to susceptibility to a bacterial pathogen
Authors: Little T. J. , Carius H.-J. , Sakwinska O. , Ebert D. 
Published: March 2003

Abstract
Costs of resistance, i.e. trade-offs between resistance to parasites or pathogens and other fitness components, may prevent the fixation of resistant genotypes and therefore explain the maintenance of genetic polymorphism for resistance in the wild. Using two approaches, the cost of resistance to a sterilizing bacterial pathogen were tested for in the crustacean Daphnia magna. First, groups of susceptible and resistant hosts from each of four natural populations were compared in terms of their life-history characteristics. Secondly, we examined the competitiveness of nine clones from one population for which more detailed information on genetic variation for resistance was known. In no case did the results show that competitiveness or life history characteristics of resistant Daphnia systematically differed from susceptible ones. These results suggest that costs of resistance are unlikely to explain the maintenance of genetic variation in D. magna populations. We discuss methods for measuring fitness and speculate on which genetic models of host-parasite co-evolution may apply to the Daphnia-microparasite system.
Polystyrene derivatives as candidates for extracorporeal adsorption of Factor VIII antibodies in the management of haemophiliac patients
Authors: Boisson‐Vidal C. , Haouam M. , Lakhiari H. , Huguet H. , Dahri L. , Sultan Y. , Jozefonvicz J. , Siali R. 
Published: March 2003

Background and Objectives This article presents a new approach for removing the Factor VIII inhibitors (anti‐FVIII) in haemophiliac patients by immunoadsorption using an affinity matrix.Materials and Methods Ten blood samples from haemophiliac patients with anti‐FVIII were assayed for antibodies, total immunoglobulins, procoagulant proteins and complement C3 protein after circulation over one or two columns filled with the polymers under investigation.Results These new synthetic sorbents are able to remove in vitro 90% of anti‐FVIII from haemophiliac plasma with inhibitors (up to 540 Bethesda Units/ml). Neither coagulation factor adsorption nor effects on complement system activation were observed.Conclusions The data presented clearly show that these polymers allow a rapid and efficient reduction of inhibitor titre. In view of the parameters studied, these polymers fulfil the requirements for use in a blood purification process to decrease high inhibitor titres without losing essential proteins.
Circulation and distribution of autotransfused fresh, liquid‐preserved and cryopreserved baboon platelets
Authors: Valeri C. R. , Giorgio A. , Macgregor H. , Ragno G. 
Published: March 2003

Background and Objectives Studies were carried out in five healthy male baboons to determine the 111indium oxine (111In‐oxine) survival of autologous fresh, liquid‐preserved and cryopreserved platelets. Simultaneous organ‐distribution studies were performed to determine the percentage uptake of platelets by the spleen and/or liver.Materials and Methods Each of five baboons was transfused, on three different occasions, with autologous fresh platelets stored at 22 °C for 18 h, liquid‐preserved platelets stored at 22 °C for 5 days and washed previously frozen platelets, labelled with 111In‐oxine.Results In vivo recovery at 2 h was 81% for the fresh platelets, 54% for the previously frozen platelets and 44% for the 5‐day‐old liquid‐preserved platelets. The weighted mean life span was 5·4 days for fresh platelets, 4·2 days for previously frozen platelets and 2 days for liquid preserved platelets. Increased radioactivity was detected over the liver 2 h after transfusion for both the previously frozen and liquid‐preserved platelets.Conclusions Cryopreserved platelets and liquid‐preserved platelets stored at 22 °C for 5 days had reduced survival 2 h post‐transfusion and reduced life span values compared to fresh platelets. In addition, the finding of increased radioactivity over the liver in the baboons that received cryopreserved and liquid‐preserved platelets suggested that the liver was the site for removal of the non‐viable platelets.
Hautschutz‐ oder Hautregenerationscreme? Der Halbseitenversuch in der Bewertung eines hautpflegenden Externums
Authors: Löffler H. , Effendy I. 
Published: March 2003

Zusammenfassung: Pflegende Externa genießen den Ruf, bei irritativen Einflüssen auf die Haut eine therapeutische sowie schützende Wirkung zu haben. Leider ist bei vielen Externa eine Überprüfung dieses Anspruches entweder gar nicht, oder nur ungenügend durchgeführt worden. Mit dem vorgestellten Testdesign wird versucht, am Beispiel einer Hautpflegecreme aufzuzeigen, ob ein Halbseitenversuch geeignet ist, die Eigenschaften eines Produktes (eher Hautschutz‐ oder Hautregenerationscreme) herauszuarbeiten.

An 30 hautgesunden Probanden wurde ein Waschversuch mit Natriumlaurylsulfat an beiden Unterarmen durchgeführt. Eine Gruppe (15 Probanden) cremte sich 30 Minuten vor der Waschung einen Unterarm ein, und die andere Gruppe cremte sich 30 Minuten nach der Waschung einen Unterarm ein. Der andere Unterarm wurde in beiden Gruppen nicht eingecremt. Es zeigte sich bei den eingecremten Unterarmen eine geringere Schädigung der Wasserpermeabilitätsbarriere (evaluiert durch Messung des TEWL) sowie eine höhere Hautfeuchtigkeit als an dem nicht behandelten Arm. Die Behandlung nach der Waschung war dabei deutlich effektiver als die vor der Waschung. Mit diesem Testdesign ist es demnach möglich, den Unterschied zwischen dem protektiven und dem regenerativen Effekt eines Externums herauszuarbeiten. Die untersuchte Hautpflegecreme zeigte im Wesentlichen eine regenerative Wirkung.
An Opportunity for Fast and Reliable Evaluation of Winter Oilseed Rape Frost Resistance Using in vitro Cultures
Authors: Rapacz M. , Dawid K. 
Published: March 2003

An attempt has been made to work out a simple and reliable method of fast frost resistance evaluation of winter oilseed rape using in vitro cultures. In winter rape cv. Górczański, there was investigated cold acclimation ability of hypocotyle sections from 5‐days old seedlings and also of callus tissue formed on these sections after subsequent 4 weeks growth on induction medium. It has been found that hypocotyle sections are unable to cold‐acclimate. Winter rape calli acclimated well and optimum conditions for acclimation is fortnight’s growth at +2°C. Exposure to light during hardening was not necessary for acquiring maximum resistance. On five winter rape cultivars freezing tests were performed using the best cold acclimation conditions. The differences in resistance between hypocotyle sections did not match the differences in field survival or frost resistance of whole plants. As distinct from hypocotyle sections callus tissue appeared to be suitable for evaluation of frost resistance. However, to ensure the objectiveness of assessment in this method is not so easy. The testing temperature must be chosen carefully, because the results can be reliable only at sufficiently low temperature. For correct estimation of the frost resistance level, it is possible to use both the decrease of triphenyltetrazolium chloride reduction rate during freezing and the increase of callus dry weight during 14 days after freezing.(Abbreviations: BAP — 6‐Benzylaminopurine; 2,4‐D — 2,4‐dichlorophenoxyacetic acid; LT50 — temperature at which 50 % of the plants (or plant material) has been frost killed; MS(0.5;2) — Moorashige and Skoog Basic Medium with addition of 0.5 mg 2.4‐D and 2 mg BAP; PPFD — photosynthetic photon flux density; TTC — 2,3,5 triphenyltetrazolium chloride)
Comparison of European Fibre Flax (Linum usitatissimum) Cultivars under Eastern Canadian Growing Conditions
Authors: Couture S. J. , Asbil W. L. , DiTommaso A. , Watson A. K. 
Published: March 2003

AbstractRenewed interest in natural fibres, decreasing subsidies to European producers, and high production costs have led the move to reintroduce fibre flax (Linum usitatissimum L.) production into eastern Canada. Research was conducted at the Macdonald Campus of McGill University, Québec, Canada in 1998 and 1999 and at Winchester and Kemptville, Ontario, Canada in 1998, to assess the performance of seven European fibre flax cultivars. Parameters evaluated included plant density, branching ratio, stem diameter, fresh and dry biomass, and mean harvest height. Data from all sites and years were subjected to a pooled anova where appropriate. The cultivar main effect was detected for all parameters measured, with the exception of mean fresh weight and mean height at harvest. There was also a site main effect for all parameters except for branching ratio. A cultivar–site interaction was found for all parameters except for mean stem diameter and mean dry weight. Results indicate a strong potential for producing fibre flax in eastern Canada using currently available European cultivars.
Lack of evidence for bovine Y‐chromosomal variation in beef traits. A Bayesian analysis of Simmental data
Authors: Reinsch By N. , Engellandt T. , Schild H. ‐J. , Kalm E. 
Published: March 2003

IntroductionY‐chromosomal loci are genetically responsible for some male‐specific biological processes. The sex determining region Y (SRY), a protein with DNA‐binding activity, is known as the trigger for sex differentiation in mammals. In humans the SRY is encoded by a single exon located on the short arm of the Y chromosome, close to the pseudoautosomal boundary (S inclair et al. 1990). Moreover, the Y chromosome harbours the male‐specific histocompatibility antigen (reviewed by S
impson et al. 1997) and there are at least two regions of the Y chromosome, which have been shown to be essential for normal spermatogenesis in mice (E
lliott and C
ooke 1997).The sexual dimorphism of aggression in mice has led to a search for its foundation on the Y chromosome. The existence of Y‐chromosomal genetic variation for aggressiveness with genetic factors borne both on the pseudoautosomal (YPAR) and on the nonpseudoautosomal (YNPAR) region of the Y chromosome (S luyter et al. 1996) has been shown. Another example for Y‐induced genetic variation in mice is the testis autosomal trait (occurrence of ovaries or ovotestes in XY animals), which is observed when specific Y chromosomes interact with the autosomal background of certain laboratory mouse lines (E
isner et al. 1996). A comparison of the resemblance of different types of relatives indicated a nonzero Y‐chromosomal variance for body weight in mice (B&
uuml;
nger et al. 1995).In cattle the Y chromosomes of the Bos taurus and Bos indicus subspecies can be morphologically distinguished: its shape is submetacentric in B. taurus and acrocentric in B.indicus. This difference is caused by a pericentric inversion (G
oldammer et al. 1997) and has frequently been used to investigate the introgression of zebu genes into B. taurus breeds.The polymorphism of the bovine Y chromosome itself and the results of mouse research both direct the scientific curiosity on the possible contribution of the bovine Y chromosome to quantitative genetic variation in cattle, a question which, to the authors’ knowledge, has not been investigated before. In this paper we first discuss the contribution of autosomal, imprinted, and sex‐linked genes to the resemblance of full and half sibs and then present a Bayesian estimation of a Y‐chromosomal variance component for each of four beef traits in young Simmental bulls using mixed linear and threshold models.
Variance of actual inbreeding derived from the number and variance of chromosome segment
Authors: Oikawa By T. , Sato K. , Takahashi S. 
Published: March 2003

IntroductionThe inbreeding coefficient (F) is used as a central parameter inferring a proportion of alleles identical by descent within an individual and by genetic variability within a population. The actual inbreeding coefficient varies around a central value, the inbreeding coefficient. C
ockerham and W
eir (1983) derived the method for computing the variance of inbreeding while reviewing several other methods. The variance of inbreeding in their report was considered to be of two components: one within population and the other between population of varied pedigrees. If pedigree is fixed, F is easily computed for an individual by the standard method (F
alconer 1989). For domestic animals, pedigree information is usually available because it is requisite for a programme of genetic improvement. In this study, the variance of inbreeding coefficient was derived for an individual with a pedigree having a single path to a foundation animal.
Einfluß eines alimentären Calcium‐ und Zinkmangels auf die Aktivitäten Calmodulin‐regulierter Enzyme in verschiedenen Geweben der Ratte
Authors: Schmidmayer S. , Roth H. ‐P. , Kirchgessner M. 
Published: March 2003

EinleitungZink übernimmt im tierischen und menschlichen Organismus viele biochemische Funktionen, so daß ein alimentärer Mangelzustand an diesem essentiellen Spurenelement zu massiven Stoffwechselstörungen und drastischen Mangelerscheinungen führt. Ebenso von essentieller Bedeutung für den Organismus ist aber auch das Mengenelement Calcium, das u.a. sowohl als Signalübermittler an der interzellulären Kommunikation als auch an der Aktivierung von Enzymen ganz wesentlich beteiligt sein kann. Die Regulierung und Aktivierung solcher Ca2+‐abhängiger Enzyme erfolgt meist über eine Bindung von Ca2+ an Calmodulin, ein niedermolekulares Protein mit vier Ca2+‐Bindungsstellen, das in allen Säugetierzellen vorkommt (C
heung 1980, 1982; B
rostrom and W
olff 1981; O
ldham 1982; W
alsh 1983; P
eersen et al. 1997) und für den Ablauf vieler biologischer Prozesse im Körper von großer Bedeutung ist. Zink hat aber ebenfalls einen Einfluß auf die Funktion von Calmodulin im Organismus (R
oth and K
irchgessner 1988, 1991a) und damit auch auf die Aktivierung dieser Enzyme (S
chmidmayer et al. 1999). In Zusammenhang mit diesen Fragestellungen wurden wachsende Ratten mit entsprechenden Diäten in einen alimentären Zink‐, Calcium bzw. in einen kombinierten Zink‐ und Calciummangel versetzt und dann die Aktivitäten von Calmodulin‐regulierten Enzymen wie der Ca–Mg–ATPase in der Erythrozytenmembran, der Phosphodiesterase und der Adenylat‐Cyclase in verschiedenen Geweben der Tiere bestimmt.
Energiebilanz bei energetischer Unterversorgung mit einer isokalorischen Kohlenhydrat‐oder Fettration am Sauenmodell
Authors: Müller . Von H. L. , KirchgeiNer M. 
Published: March 2003

EinleitungEine dauerhafte Reduktion der Energiezufuhr wird bei Übergewicht aus trivialem biophysikalischem Grund zwangsläufig zur Gewichtsverminderung führen. Die Praktikabilität eines solchen Vorgehens in der Ernährung des Menschen erweist sich aber vielfach als schwierig. Das Interesse ist deshalb mehr darauf gerichtet, weniger durch bewuite Einschränkung der Energiezufuhr als vielmehr durch Änderung der Nahrungszusammensetzung einen günstigen Einflui auf die Energiebilanz zu erreichen. Ein viel diskutiertes Problem ist in diesem Zusammenhang die Relation des Kohlenhydrat‐ und Fettanteils in der Nahrung. Nach mehreren Befunden am Menschen wird den Kohlenhydraten eine regulative Funktion zugeschrieben, wobei die Kohlenhydratbilanz über Oxidation dieses Nährstoffes ausgeglichen wird. Demgegenüber wird die Fettbilanz nicht ausgeglichen, so dai überschüssige Fettzufuhr zu einem entsprechenden Ansatz von Körperenergie führt (F latt 1993, 1995; J&
eacute;
quier 1993). In exakten Energiebilanzversuchen mit Sauen wurde jedoch gefunden, dai Kohlenhydrate und Fette im Erhaltungsbereich als gleichwertige Energielieferanten (ATP‐Effizienz) zu sehen sind. Im Überschuibereich lieferten Fette einen höheren Energieansatz als Kohlenhydrate, wobei sich die Differenz durch die unterschiedlichen Energiekosten für die Fettbildung erklären liei (sog. obligatorische Thermogenese). Eine eigentliche regulative Funktion (fakultative Thermogenese) der Kohlenhydrat‐Fett‐Relation auf die Energiebilanz konnte nicht festgestellt werden (KIRCHGEiNER und M&
uuml;
ller 1998; M&
uuml;
ller und KIRCHGEiNER 1998). Nach diesen Ergebnissen sollte man erwarten, daß eine kohlenhydratreiche oder fettreiche Reduktionsdiät sich ebenfalls nicht unterschiedlich auf die Gewichtsreduktion auswirkt. Im vorliegenden Versuch wurde dies bei streng kontrollierter kalorischer Unterversorgung an Sauen überprüft.
Nutrient oxidation and lipogenesis in hens
Authors: Chwalibog A. , Thorbek G. 
Published: March 2003

Introduction  Indirect calorimetry based on measurements of gas exchange has been used successfully during the last century in order to estimate energetic values of feedstuffs and animals’ requirement for nutrients and energy. Recently, measurements of gas exchange have been used to calculate nutrient oxidation and lipogenesis in the intact body of man (T
horbek et al. 1994), pigs (C
hwalibog et al. 1992; C
hwalibog and T
horbek 1995), calves (C
hwalibog et al. 1996; C
hwalibog et al. 1997a), mink (T
auson et al. 1997) and rats (C
hwalibog et al. 1998).In the present paper a similar approach has been used to quantify nutrient metabolism in laying hens in accordance with a calculation method first proposed by C hwalibog et al. (1992) and later modified as outlined in Fig. 1.According to this biological model digested protein (DP) which is equal to PROT – group is utilized for retention in eggs (OP), ovary and body (OBP), whereas deaminated amino acids are oxidized (OXP) with concomitant excretion of energy with nitrogenous substances in urine (UEN) and contribution of energy (GLUC) to carbohydrate metabolism. Digested carbohydrate (DCHO) together with GLUC constitute the CHO – group, which is retained in eggs (OCHO), oxidized (OXCHO) and used for lipogenesis (LIPO). Digested fat (DFAT) and lipids from lipogenesis constitute the FAT – group, which is incorporated into eggs (OF), ovary + body (OBF) and oxidized (OXF). Both CHO and FAT metabolism contribute with energy containing products excreted with urine (UEN‐free). The energy from OXP, OXCHO and OXF make up the total heat production (HE). The validity of the method will be discussed later.The aim of this study was to demonstrate how data from gas exchange measurements in combination with nitrogen and energy balances can be applied in order to calculate nutrient oxidation and the quantities of substrates used for retention and lipogenesis processes, and furthermore, to elucidate differences in nutrient oxidation and lipogenesis in relation to different housing conditions and genotypes of laying hens.