Equal Proportions (equal + proportion)

Distribution by Scientific Domains
Distribution within Life Sciences


Selected Abstracts


Factors influencing the effectiveness of an attracticide formulation against the Oriental fruit moth, Grapholita molesta

ENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 2 2004
Maya L. Evenden
Abstract An attracticide formulation, LastCallÔOFM, was tested against the Oriental fruit moth Grapholita molesta (Busck) (Lepidoptera: Tortricidae) in replicated small plot field trials in apple, Malus domestica (Borkhausen), orchards in South-eastern Pennsylvania, USA. Attracticide treatments were applied using a calibrated hand pump, and treated plots were compared to similar untreated plots. Male moth activity was monitored using virgin female-baited traps, and the potential for reduction in mating activity was assessed using sentinel virgin females. A comparison of application rates showed that 1500 droplets per ha of the attracticide formulation was as effective as 3000 droplets per ha, and both application rates reduced captures in synthetic pheromone-baited traps for prolonged periods. Droplets placed either at high or low positions within the canopy significantly reduced trap capture and mating with sentinel females. In addition, the only sentinel females that mated in the treated plots were located in the untreated portion of the tree canopy. Mate finding behaviour was equally disrupted by formulations with and without insecticide. Therefore, under the test conditions, the mechanism by which the attracticide formulation worked was by disruption of male orientation, and not by the removal of males due to insecticide poisoning. Two field cage experiments tested the impact of population density on the competitiveness of the attracticide formulation compared to virgin females. A significant proportion of males were captured in female-baited traps at the highest female-to-droplet ratio tested. Equal proportions of males were captured in attracticide-baited traps at male moth densities of 10, 20, 40, and 80 males per cage. These results clarify some of the factors influencing the effectiveness and possible mechanisms of an attracticide management tactic against the Oriental fruit moth. [source]


Women's and health professionals' preferences for prenatal testing for Down syndrome in Australia

AUSTRALIAN AND NEW ZEALAND JOURNAL OF OBSTETRICS AND GYNAECOLOGY, Issue 3 2006
Sharon M. LEWIS
Abstract Aim:, To describe and compare women's and health professionals' preferences for prenatal screening tests for Down syndrome. Design:, Cross-sectional questionnaire survey. Participants and setting:, Women (n = 322) attending for a glucose challenge test at 26 weeks gestation and health professionals (266 midwives and 34 obstetricians) at the Royal Women's Hospital, Melbourne, between 13 December 2002 and 30 April 2003. Outcome measures:, The relative value participants attach to attributes of Down syndrome screening tests as determined by conjoint analysis and ranking scales. Results:, Women and health professionals shared similar relative values regarding the importance of detection rate of screening tests, according to coefficients from conjoint analysis models. However, health professionals placed higher relative values on timing of prenatal tests and risk associated with the subsequent diagnostic test than did women. Comparison of coefficients suggests that, compared with health professionals, women would wait longer and accept a greater decrease in detection rate for a test if it was safer. Using the more traditional ranking scale, the safest test was ranked first by 56% of women while 47% of health professionals ranked a test with the highest detection rate first. Equal proportions (,10%) in both groups ranked the earliest test first. Conclusion:, There is a general agreement between pregnant women and health professionals regarding the relative importance they attach to different attributes of a test. However, health professionals appeared to favour earlier timing of tests while women placed greater emphasis on safety. Utilising two different measures of preference demonstrated the complexity of decision-making. [source]


Paediatric utilization of a general emergency department in a developing country

ACTA PAEDIATRICA, Issue 8 2003
AY Goh
Aim: Knowledge of the spectrum and frequencies of paediatric emergencies presenting to an emergency department (ED) of individual developing countries is vital in optimizing the quality of care delivered locally. Methods: A prospective 6 wk review of all paediatric (< 18y) attendees to an urban ED was done, with patient age, presenting complaints, diagnoses, time of arrival and disposition recorded. Results: Complete data were available on 1172 patients, with an age range of 4 d to 18 y (mean ± SD 6.9 ± 5.6 y); 43% were aged ,4 y. The main presenting complaints were injuries (26.9%), fever (24%) and breathing difficulties (16.6%). The most common diagnosis was minor trauma (24.2%), with soft-tissue injuries predominating (80.6%). The other diagnoses were asthma (12.6%), upper respiratory infections (12.1%), other infections (12.1%) and gastroenteritis (11.8%). Equal proportions of patients were seen throughout the day. 25% of patients were admitted. Young age (<1 y); presence of past medical history, general practitioner referrals, diagnosis of bronchiolitis and pneumonia were significantly associated with risk of admission. Conclusion: A wide spectrum of paediatric illnesses was seen in the ED, with an overrepresentation of young children. This supports the decision to have either a separate paediatric ED or paediatric residents on the staff. The training curricula should emphasize the management of paediatric trauma, infections and asthma. Alternatively, developing guidelines for the five most common presenting complaints would account for 82% of all attendees and could be directed towards all staff on the ED. [source]


Growth rates of phytoplankton under fluctuating light

FRESHWATER BIOLOGY, Issue 2 2000
Elena Litchman
Summary 1The effect of light fluctuations on the growth rates of four species of freshwater phytoplankton was investigated. Experimental light regimes included constant irradiance and fluctuations of a step function form, with equal proportion of high (maximum of 240 µmol photons m -2 s -1) and low light (minimum of 5 µmol photons m -2 s -1) (or dark) in a period. Fluctuations of 1, 8 and 24-h periods were imposed over several average irradiances (25, 50, 100 and 120 µmol photons m -2 s -1). 2Growth rate responses to fluctuations were species-specific and depended on both the average irradiance and the period of fluctuations. Fluctuations at low average irradiances slightly increased growth rate of the diatom Nitzschia sp. and depressed growth of the cyanobacterium Phormidium luridum and the green alga Sphaerocystis schroeteri compared to a constant irradiance. 3Fluctuations at higher average irradiance did not have a significant effect on the growth rates of Nitzschia sp. and Sphaerocystis schroeteri (fluctuations around saturating irradiances) and slightly increased the growth rates of the cyanobacteria Anabaena flos-aquae and Phormidium luridum (when irradiance fluctuated between limiting and inhibiting levels). 4In general, the effect of fluctuations tended to be greater when irradiance fluctuated between limiting and saturating or inhibiting levels of a species growth-irradiance curve compared to fluctuations within a single region of the curve. 5The growth rates of species under fluctuating light could not always be predicted from their growth-irradiance curves obtained under constant irradiance. When fluctuations occur between limiting and saturating or inhibiting irradiances for the alga and when the period of fluctuations is long (greater than 8 h), steady-state growth-irradiance curves may be insufficient to predict growth rates adequately. Consequently, additional data on physiological acclimation, such as changes in photosynthetic parameters, may be required for predictions under non-constant light supply in comparison to constant conditions. [source]


High specificity generally characterizes mycorrhizal association in rare lady's slipper orchids, genus Cypripedium

MOLECULAR ECOLOGY, Issue 2 2005
RICHARD P. SHEFFERSON
Abstract Lady's slipper orchids (Cypripedium spp.) are rare terrestrial plants that grow throughout the temperate Northern Hemisphere. Like all orchids, they require mycorrhizal fungi for germination and seedling nutrition. The nutritional relationships of adult Cypripedium mycorrhizae are unclear; however, Cypripedium distribution may be limited by mycorrhizal specificity, whether this specificity occurs only during the seedling stage or carries on into adulthood. We attempted to identify the primary mycorrhizal symbionts for 100 Cypripedium plants, and successfully did so with two Cypripedium calceolus, 10 Cypripedium californicum, six Cypripedium candidum, 16 Cypripedium fasciculatum, two Cypripedium guttatum, 12 Cypripedium montanum, and 11 Cypripedium parviflorum plants from a total of 44 populations in Europe and North America, yielding fungal nuclear large subunit and mitochondrial large subunit sequence and RFLP (restriction fragment length polymorphism) data for 59 plants. Because orchid mycorrhizal fungi are typically observed without fruiting structures, we assessed fungal identity through direct PCR (polymerase chain reaction) amplification of fungal genes from mycorrhizally colonized root tissue. Phylogenetic analysis revealed that the great majority of Cypripedium mycorrhizal fungi are members of narrow clades within the fungal family Tulasnellaceae. Rarely occurring root endophytes include members of the Sebacinaceae, Ceratobasidiaceae, and the ascomycetous genus, Phialophora. C. californicum was the only orchid species with apparently low specificity, as it associated with tulasnelloid, ceratobasidioid, and sebacinoid fungi in roughly equal proportion. Our results add support to the growing literature showing that high specificity is not limited to nonphotosynthetic plants, but also occurs in photosynthetic ones. [source]


Four new species of Rhodophyceae from Fiji, Polynesia and Vanuatu, South Pacific

PHYCOLOGICAL RESEARCH, Issue 1 2009
Antoine D. R. N'Yeurt
SUMMARY Four new species of Rhodophyceae are described from the South Pacific, with type localities in Fiji, French Polynesia and Vanuatu. Chondria bullata from the Tuamotus (French Polynesia), Vanuatu, Palmerston Atoll (Cook Islands) and Fiji is unique owing to its non-constricted axes with markedly protruding, bubble-like cortical cells. Halymenia nukuhivensis, from the Marquesas Islands in French Polynesia, is distinguished from others in the genus by its dichotomous, papery blades issued from a strap-shaped basal region, and the equal proportion of anti-clinal, periclinal and oblique filaments in its medullary layer. Jania articulata, so far known only from the Tuamotus in French Polynesia and Manihiki in the Northern Cook Islands, superficially resembles the genus Amphiroa with its articulated branches with numerous genicula between successive dichotomies, and its large axis diameter. Meristotheca peltata from the Fiji Islands is unique among the genus by its distinctly peltate, erect habit. The recent high number of newly described species from the South Pacific region emphasizes the need for more in-depth surveys, particularly in deeper outer reef slope habitats, which remain for the most part unexplored and could yield particularly interesting new taxa or distributional records. [source]


Outcome of Pulmonary Valve Replacements in Adults after Tetralogy Repair: A Multi-institutional Study

CONGENITAL HEART DISEASE, Issue 3 2008
Thomas P. Graham Jr. MD
ABSTRACT Objective., The purpose of this study was to assess the outcome of pulmonary valve replacement (PVR) in adults with moderate/severe pulmonary regurgitation after tetralogy repair, with particular emphasis on patient outcome, durability of valve repair, and improvement in symptomatology. Design/Setting/Patients., The project committee of the International Society of Congenital Heart Disease undertook a retrospective multi-institutional analysis of PVR. Seven centers participated in submitting data on 93 patients >18 years of age who had the operation performed and follow-up obtained. The average age of PVR was 26± years (median 27 years). Time of follow-up after replacement was 3 years (range 4 days,28 years). Outcomes/Measures/Results., Kaplan,Meier estimates of durability of PVR showed approximately 50% replacement at 11 years. There were two deaths at 6 and 12 months after valve replacement. Right ventricular (RV) size estimated by echocardiography from pre- to postoperative studies decreased in 81% (P < 0.001 testing for equal proportions), but RV systolic function increased in only 36% (P = 0.09). Ability index improved in 59% (P < 0.001) and clinical heart failure status improved in 57% with this problem before PVR. PVR did not improve arrhythmia status in a small group of patients. Conclusions., PVR is associated with low mortality, decrease in RV size and improvement in ability index, and uncertain effects on RV systolic function. Average valve durability was approximately 11 years. Criteria for PVR that will preserve RV function are not clearly identified, and management of these patients remains a difficult enterprise. [source]


Export of nitrogenous compounds due to incomplete cycling within biological soil crusts of arid lands

ENVIRONMENTAL MICROBIOLOGY, Issue 3 2007
Shannon L. Johnson
Summary Second only to water among limiting factors, nitrogen controls the fertility of most arid regions. Where dry and wet depositions are weak, as in the western US deserts, N inputs rely heavily on biological N2 fixation. Topsoil cyanobacterial communities known as biological soil crusts (BSCs) are major N2 fixation hot spots in arid lands, but the fate of their fixed N remains controversial. Using a combination of microscale and mesoscale process rate determinations, we found that, in spite of theoretically optimal conditions, denitrification rates in BSCs were paradoxically immaterial for nitrogen cycling. Denitrifier populations within BSCs were extremely low. Because of this absence of denitrification, and because of the limitation of respiration and ammonia oxidation by diffusive O2 supply, we could demonstrate that BSCs function as net exporters of ammonium, nitrate and organic N to the soils they cover, in approximately stoichiometrically equal proportions. Overall export rates during periods of biological activity are in the range of tens to hundreds of ,mol-N m,2 h,1, commensurate with those of N2 fixation. These results explain the long-term dependence of BSCs on N2 fixation, confirm their role in landscape fertility, and provide a robust argument for conservation of these endangered communities. [source]


Heterogeneity of V2-derived interneurons in the adult mouse spinal cord

EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 11 2007
A. Al-Mosawie
Abstract Spinal neurons and networks that generate rhythmic locomotor activity remain incompletely defined, prompting the use of molecular biological strategies to label populations of neurons in the postnatal mouse. During spinal cord development, expression of Lhx3 in the absence of Isl1 specifies a V2 interneuronal fate. In this study, postnatal V2-derived interneurons were identified by yellow fluorescent protein (YFP) expression in the double-transgenic offspring of Lhx3Cre/+ × thy1-loxP-stop-loxP-YFP mice. While some motoneurons were labelled, several populations of interneurons predominantly located in lamina VII could also be distinguished. Small interneurons were located throughout the spinal cord whereas larger interneurons were concentrated in the lumbar enlargement. Some V2-derived interneurons were propriospinal, with axons that bifurcated in the lateral funiculus. V2-derived interneurons gave rise to populations of both excitatory and inhibitory interneurons in approximately equal proportions, as demonstrated by in situ hybridization with VGLUT2 mRNA. Immunohistochemical studies revealed YFP+ boutons throughout the spinal cord. Both glutamatergic and glycinergic YFP+ boutons were observed in lamina IX where many apposed motoneuron somata. GABAergic YFP+ boutons were also observed in lamina IX, and they did not form P-boutons. At P0, more than half of the YFP+ interneurons expressed Chx10 and thus were derived from the V2a subclass. In adult mice, there was an increase in Fos expression in V2-derived interneurons following locomotion, indicating that these neurons are active during this behaviour. The heterogeneity of V2-derived interneurons in adult mice indicates that physiologically distinct subpopulations, including last-order interneurons, arise from these embryonically defined neurons. [source]


Constitutive expression of the low-affinity neurotrophin receptor and changes during axotomy-induced death of sensory neurones in the neonatal rat dorsal root ganglion

JOURNAL OF ANATOMY, Issue 2 2003
Simon S. Murray
Abstract Sensory neurones in the dorsal root ganglion (DRG) of the neonatal rat express the 75-kDa low-affinity neurotrophin receptor (p75NTR) and these neurones degenerate rapidly after axotomy. p75NTR belongs to the tumour necrosis factor superfamily, several members of which have a role in cell death and it is constitutively expressed within a subpopulation of DRG neurones. p75NTR has been implicated in mediating the degeneration of these neurones after axotomy. In this study, we characterize the expression of p75NTR in sensory neurones of the newborn rat DRG using immunohistochemistry. Furthermore, we investigate the change in constitutive expression pattern of p75NTR in these neurones following axotomy. In the C7 and C8 DRG of the newborn rat, p75NTR is expressed in approximately 70% of DRG neurones. Those expressing p75NTR can be classified into subpopulations with moderate or intense p75NTR expression, each present in approximately equal proportions. Whilst p75NTR expression is observed in neurones throughout the entire neuronal diameter range, a correlation exists between neuronal diameter and p75NTR expression intensity. We also found that the most vulnerable population following axotomy were those sensory neurones which constitutively express the highest levels of p75NTR, i.e. the large-diameter neurones. [source]


Compatible blends of ethylene-vinyl acetate copolymer and hydrogenated nitrile rubber

ADVANCES IN POLYMER TECHNOLOGY, Issue 1 2004
P. Thavamani
Abstract The miscibility and some physico-mechanical characteristics of ethylene vinyl acetate (EVA) copolymer and hydrogenated nitrile rubber (HNBR) have been investigated using differential scanning calorimetry, dynamic mechanical and thermal analysis, and electrical conductivity. EVA was found to be miscible with HNBR at all properties. Infrared spectroscopic studies revealed that there is some chemical interaction between the constituent polymers. Scanning electron microscopic observations on the morphology of preferential solvent extracted samples indicated that in the blend the major constituent forms a continuous matrix in which the minor one is dispersed. At equal proportions, both EVA and HNBR exist as discontinuous phase. Variation of strength properties with blend composition is also discussed. © 2004 Wiley Periodicals, Inc. Adv Polym Techn 23: 5,17, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.10066 [source]


Sexual selection maintains whole-body chiral dimorphism in snails

JOURNAL OF EVOLUTIONARY BIOLOGY, Issue 5 2007
M. SCHILTHUIZEN
Abstract Although the vast majority of higher animals are fixed for one chiral morph or another, the cause for this directionality is known in only a few cases. In snails, for example, rare individuals of the opposite coil are unable to mate with individuals of normal coil, so directionality is maintained by frequency-dependent selection. The snail subgenus Amphidromus presents an unexplained exception, because dextral (D) and sinistral (S) individuals occur sympatrically in roughly equal proportions (so-called ,antisymmetry') in most species. Here we show that in Amphidromus there is sexual selection for dimorphism, rather than selection for monomorphism. We found that matings between D and S individuals occur more frequently than expected by chance. Anatomical investigations showed that the chirality of the spermatophore and the female reproductive tract probably allow a greater fecundity in such inter-chiral matings. Computer simulation confirms that under these circumstances, sustained dimorphism is the expected outcome. [source]


Common sex-linked deleterious alleles in a plant parasitic fungus alter infection success but show no pleiotropic advantage

JOURNAL OF EVOLUTIONARY BIOLOGY, Issue 3 2006
T. GIRAUD
Abstract Microbotryum violaceum is a fungus that causes the sterilizing anther smut disease in Caryophyllaceae. Its diploid teliospores normally produce equal proportions of haploid sporidia of its two mating types. However natural populations contain high frequencies of individuals producing sporidia of only one mating type (,biased strains'). This mating type-ratio bias is caused by deleterious alleles at haploid phase (,haplo-lethals') linked to the mating type locus that can be transmitted only by intra-tetrad selfing. We used experimental inoculations to test some of the hypotheses proposed to explain the maintenance of haplo-lethals. We found a disadvantage of biased strains in infection ability and high intra-tetrad mating rates. Biased strains had no higher competitive ability nor shorter latency and their higher spore production per flower appeared insufficient to compensate their disadvantages. These findings were only consistent with the hypothesis that haplo-lethals are maintained under a metapopulation structure because of high intra-tetrad selfing rates, founder effects and selection at the population level. [source]


MIXTURES OF BEEF TRIPE, BEEF LIVER AND SOYBEANS APPLIED TO FOOD DEVELOPMENT

JOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 3 2007
L. MALVESTITI
ABSTRACT A nutritive sausage-type product was developed with beef tripe, beef liver and soybeans as ingredients. A three-component mixture design was used to obtain seven different formulations (minimum of each main ingredient: 16.5%, maximum: 67.0%). Ingredients were ground, mixed and packed tightly with a polypropylene film to obtain a roll. Pieces were cooked in boiling water for 90 min. The composition of the obtained products varied within the following ranges: proteins 17.32,25.56 g/100 g, lipids 3.22,3.87 g/100 g, crude fiber 1.50,4.50 g/100 g, minerals 1.44,2.72 g/100 g. Total iron levels varied between 1.39 and 2.98 mg/100 g and calcium levels between 15.07 and 34.01 mg/100 g. Surface response analysis was applied to parameters obtained from texture profile analysis (hardness, adhesiveness, cohesiveness and elasticity). Products hardness increased when the soy content increased; on the contrary, formulations enriched in beef tripe were those of higher elasticity and cohesiveness. Color was mainly determined by the incorporation of liver. A nontrained panel was used to evaluate the acceptance of the different formulations. The most accepted one was that with equal proportions of the three main ingredients. Microbiological challenge testing showed that the thermal treatment was enough for assuring the product safeness even in samples with high initial microbial charge. [source]


Maternal parity affects neonatal survival rate in a colony of captive bred baboons (Papio hamadryas)

JOURNAL OF MEDICAL PRIMATOLOGY, Issue 5 2008
Neroli Sunderland
Abstract Background, Non-human primates, particularly baboons, are valuable as animal models for reproductive research, because of their similarity to humans. Knowledge of colony-specific pregnancy and neonatal outcomes is essential for interpretation of such research. Methods, A retrospective review of the reproductive records of the Australian National Baboon Colony (ANBC) from 1994 to 2006 was performed. Results, The overall live birth rate was over 70% of recognized pregnancies. Pregnancy loss was due to equal proportions of spontaneous abortion and stillbirth, and was not affected by maternal age or parity. Stillbirth rates were increased by the use of animals in novel late pregnancy experimental protocols. Neonatal mortality rates were low overall, but significantly higher in primiparous compared with multiparous mothers (P < 0.05). There were no cases of maternal mortality. Conclusions, The success of the ANBC breeding programme is demonstrated by the low rate of pregnancy loss, high neonatal survival rate and lack of maternal mortality. [source]


Competition between vectors of Chagas disease, Triatoma infestans and T. sordida: effects on fecundity and mortality

MEDICAL AND VETERINARY ENTOMOLOGY, Issue 4 2004
E. B. Oscherov
Abstract., Interspecific competition between two species of triatomine bugs (Hemiptera: Reduviidae), vectors of Chagas disease, was assessed for 16 months through comparative fecundity and mortality of experimental populations in chicken nests, maintained indoors with ambient conditions. Triatoma sordida (Stål), the secondary vector in north-eastern Argentina, was compared with Triatoma infestans (Klug) the more widespread domestic vector in the southern cone of South America. Both species populations originated from females collected in 1995 from the community of Empedrado, Corrientes, Argentina. Three population units were monitored: T. infestans alone, T. sordida alone and both species together in equal proportions. Each population started with six male and six female adults, 116 eggs, and nymphal instars I to V numbering 82, 48, 16, 11 and 19, respectively. Numbers and weight of individual bugs were recorded monthly (August 1995 to December 1996). The pure populations of T. infestans and T. sordida showed temporal changes in abundance, rising in summer and falling in winter, similar to the typical trends under normal field conditions. In the mixed population, however, T. sordida fell to extinction after 6 months, whereas T. infestans reached similar abundance to the pure (control) population. For each nymphal instar of T. sordida, the mean body weight was significantly less and mortality rate was higher in the mixed population compared to the pure population, but there were no significant differences of adult longevity or fecundity between the pure and mixed populations of T. sordida. The apparent competitive displacement of T. sordida by T. infestans was attributed to the latter species having better ability to obtain bloodmeals. This might explain the rarity of mixed populations where these two species occur in sympatry. [source]


Host concealment: a determinant for host acceptance and feeding in an ectoparasitoid wasp

OIKOS, Issue 2 2000
Takatoshi Ueno
In general, ectoparasitoids attack concealed hosts in protected situations whereas endoparasitoids use both concealed and exposed hosts. The difference is assumed to be the consequence of ecological constraints; ectoparasitic larvae are vulnerable both to predation and to climatic factors such as rainfall, and, hence, require some structures to protect themselves. I hypothesized that such ecological constraints should act as a within-species selection pressure to female ectoparasitoids, and hence that females should recognize the degree of concealment of the host and prefer concealed over exposed hosts for oviposition. To test this hypothesis, I examined 1) whether host concealment could influence host acceptance by the ectoparasitoid wasp Agrothereutes lanceolatus and 2) whether host concealment could influence the fitness of the offspring. Female wasps recognized and attacked (probed) both cocooned and exposed host prepupae in equal proportions, but discriminated between them after ovipositor insertion, and preferred the former for oviposition and the latter for host-feeding. They also selected to oviposit on hosts concealed in paper tubes. Thus host concealment was important for host selection in A. lanceolatus . Offspring fitness (measured as survival and size) was much lower on exposed hosts than on cocooned and paper-concealed hosts, even under laboratory conditions. Thus, host concealment influenced the fitness of wasp offspring, and, hence, is a good indicator of host quality for female wasps. Adaptiveness of host selection and host-feeding in A. lanceolatus in relation to host concealment is discussed. [source]


Variation in gametophyte dominance in populations of Chondrus verrucosus (Gigartinaceae, Rhodophyta)

PHYCOLOGICAL RESEARCH, Issue 4 2008
Alecia Bellgrove
SUMMARY We describe the abundance, including spatial and temporal variability, of phases of the isomorphic Chondrus verrucosus Mikami from Japan. Chondrus verrucosus occurred in a dense (,90% cover) and temporally stable bed on a small, isolated rocky outcrop (Oyakoiwa) in Shizuoka Prefecture. Small vegetative fronds were always much more abundant than large vegetative and fertile fronds over the spring to late summer periods in 1999 and 2000. Over the same period, fertile carposporophytic fronds were generally more abundant than fertile tetrasporophytic fronds, and fertile male fronds appeared infrequently at low densities. Using the resorcinol-acetal test, we determined the proportion of gametophytes and tetrasporophytes in three populations of C. verrucosus: Oyakoiwa and Noroshi (Shizuoka) in the summers of 1999 and 2000 and Kamehana Point (Miyagi) in autumn 2000. All populations had a significantly higher proportion of gametophytes than tetrasporophytes in both years, although gametophytic proportions were lower at Noroshi (,70%) than at Oyakoiwa (,80%) and Kamehana Point (,97%). However, examination of all isolated individuals sampled on Noroshi showed equal proportions of each phase in 1999, but gametophyte dominance (74%) in 2000. Differences in dispersal and spore production between phases are discussed as mechanisms potentially contributing to variation in gametophyte dominance. [source]


Isolation and Characterisation of Procyanidins from Rumex obtusifolius

PHYTOCHEMICAL ANALYSIS, Issue 3 2007
Paul Spencer
Abstract An acetone:water (7:3) extract obtained from the leaves of Rumex obtusifolius was fractionated into procyanidin oligomer and polymer fractions using a linear gradient and a simple step method on Sephadex LH-20. The chemical characteristics of the procyanidin fractions were studied by 13C-NMR spectroscopy, acid-catalysed degradation in the presence of benzyl mercaptan, matrix-assisted laser desorption/ionisation time-of-flight (MALDI-TOF) MS and electrospray ionisation (ESI) MS. The 13C-NMR showed that the polymer fraction consisted predominantly of procyanidin polymers, some with galloyl groups attached. The thiolysis reaction products indicated a mean degree of polymerisation (DP) of 4.3 for the step method, and a range of 2.3,8.2 mean DP for the gradient fractionation, with epicatechin as the most abundant flavan-3-ol extension unit, while the terminal units consisted of equal proportions of catechin, epicatechin and epicatechin gallate. Singly charged ions observed in MALDI-TOF/MS showed a range of oligomeric procyanidins and their polygalloyl derivatives. These species (in the range DP 2,7) were also observed by ESI/MS but the spectra were more complex due to overlapping multiply charged ions. Isolation of oligomers from the Sephadex LH-20 fraction by chromatography on polyamide and C18 yielded B1, B2, B3 and B7 dimers, an A-type trimer and a B2 3,3,- O -digallate. Copyright © 2007 John Wiley & Sons, Ltd. [source]


The use of microsatellite markers to determine the relative proportions of grain produced by cultivars and the frequency of hybridization in bread wheat mixtures

PLANT BREEDING, Issue 5 2003
M. Belhaj Fraj
Abstract Two polymorphic microsatellite markers were selected to identify 24 bread wheat cultivars commonly grown in France and to estimate the proportions of cultivar and hybrid grains in the harvests of four 4-cultivar mixtures (CM 1-4) planted in equal proportions in farmers' fields. This technology was used not only to determine whether a mixture comprises the declared cultivars, but also whether there is any contamination with other cultivars, to identify the contaminants and to estimate their proportions. At harvest, the cultivar proportions ranged from 15 to 37%. Only in the mixture CM2 (,Malacca', ,Somme', ,Renan' and ,Soissons'), did the cultivars contribute equally to the harvest. The other cultivar mixtures CM1 (,Malacca', ,Somme', ,Renan' and ,Camp Remy'), CM3 (,Malacca', ,Texel', ,Apache' and ,Aligre') and CM4 (,Malacca', ,Somme', ,Apache' and ,Virtuose') showed significantly unequal cultivar proportions with ,Somme' dominating ,Renan' and ,Camp Remy' in CM1, and ,Apache' dominating ,Malacca' and ,Aligre' in CM3 and ,Malacca' in CM4. Similar cultivar proportions were measured with gliadin and glutenin markers in the mixtures CM3 and CM4, confirming the results with microsatellites. No contamination was found. Hybrids accounted for between 1.3 and 6.3% of the grains produced in the four cultivar mixtures. [source]


On the structural diversity of Shiga toxin glycosphingolipid receptors in lymphoid and myeloid cells determined by nanoelectrospray ionization tandem mass spectrometry

RAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 15 2010
Petra Hoffmann
Shiga toxin (Stx, synonymous to verotoxin, VT) binds with high and low affinity to the globo-series neutral glycosphingolipids (GSLs), globotriaosylceramide (Gb3Cer or Gal,4Gal,4Glc,1Cer, also known as CD77) and globotetraosylceramide (Gb4Cer or GalNAc,3Gal,4Gal,4Glc,1Cer), respectively, which represent the targets of Stxs on many different cell types. B-cell-derived Raji cells and THP-1 cells of monocytic origin are widely used for the investigation of Stx-mediated cellular response, because Stx is known to cause cell death in both cell lines. Despite their functional importance, the Stx receptors of Raji and THP-1 cells have so far not been investigated. This prompted us to explore the structures of their GSL receptors in detail by means of nanoelectrospray ionization quadrupole time-of-flight mass spectrometry (nanoESI-QTOF-MS) with collision-induced dissociation (CID) in conjunction with Stx1 as well as anti-Gb3Cer and anti-Gb4Cer antibodies. Using the combination of a thin-layer chromatography (TLC) overlay assay and MS1 and MS2 analysis we identified Gb3Cer (d18:1, C24:1/C24:0) as the prevalent Stx1-receptor accompanied by less abundant Gb3Cer (d18:1, C16:0) in the neutral GSL fraction of Raji cells. The same Gb3Cer species but with almost equal proportions of the C24:1/C24:0 and C16:0 variants were found in THP-1 cells. In addition, unusual hydroxylated Gb3Cer (d18:1, C24:1/C24:0) and Gb3Cer (d18:1, C26:1) could be identified in trace quantities in both cell lines. As the most obvious difference between Raji and THP-1 cells we observed the expression of Gb4Cer in THP-1 cells, whereas Raji cells failed to express this elongation product of Gb3Cer. Both short- and long-chain fatty acid carrying Gb4Cer (d18:1, C16:0) and Gb4Cer (d18:1, C24:1/C24:0), respectively, were the prevalent Gb4Cer variants. This first report on the differential expression of Gb3Cer and Gb4Cer and their structural diversity in lymphoid and myeloid cell lines supports the hypothesis that such heterogeneities might play a functional role in the molecular assembly of GSLs in membrane organization and cellular signaling of Stx-susceptible cells. Copyright © 2010 John Wiley & Sons, Ltd. [source]


A new iconographical addition to Francis I's adoption of the persona of King David and its contemporary literary context

RENAISSANCE STUDIES, Issue 5 2007
Pauline M. Smith
The presence in the Cathedral at Auch of a large carved representation of Francis I as the Biblical King David on the high back panel of one of the choir stalls, turning to face, in the next stall, a carving of Bathsheba of equal proportions, raises intriguing questions, especially as archive documentation on the subject is sparse and requires contemporary literary texts to support it. This article considers how the carving fits into Francis's known iconography, who may have been responsible for commissioning it (Hippolyte d'Este was Cardinal-Archbishop of Auch at the relevant time, 1552,1554) and how Francis in the persona of David was seen by his court poet, Clément Marot, by his sister Marguerite de Navarre and by Francis himself. In addition the David-Bathsheba episode invites comparison with Francis's relationship with the Duchesse d'Etampes. Finally the penitential role of the Psalms is seen to be equally important to both kings. [source]


Presence of Subepithelial Lymphoid Nodules in the Teat of Ewes

ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 3 2007
V. S. Mavrogianni
Summary A total of 87 clinically healthy ovine teats were examined bacteriologically (by scraping the mucosa) and histologically. Teats examined were those of lactating mammary glands with no bacteria isolated (n = 23); of mammary glands after cessation of lactation with no bacteria isolated (n = 25); of lactating mammary glands with bacteria isolated (n = 22); and of mammary glands after cessation of lactation with bacteria isolated (n = 17). The salient histological feature was subepithelial leucocytic infiltration. In teat cisterns, lymphocytes were the predominant cell type and in teat ducts, lymphocytes and neutrophils were seen in equal proportions. Subepithelial lymphoid nodules, some with germinal centres, were detected in 43 (49%) teats. The majority of lymphoid nodules was observed at the border between teat duct and teat cistern. Presence of bacteria was significantly associated with the presence of leucocytic activity (P < 0.001) and with the presence of lymphoid nodules (P = 0.032). We conclude that the presence of induced subepithelial lymphoid tissue at the border between teat duct and teat cistern appears to be important in protecting the mammary gland during the early stages of bacterial invasion. The findings call for further investigations into the lymphoid structures of the teat; these should elucidate the role and development of mammary mucosa-associated lymphoid tissues and may lead to strategies for enhancing non-specific defence mechanisms of the mammary gland. [source]


Effect of fortifying concentrate supplement with fibrolytic enzymes on nutrient utilization, milk yield and composition in lactating goats

ANIMAL SCIENCE JOURNAL, Issue 3 2009
Prokasananda BALA
ABSTRACT Thirty lactating Beetle-sannen crossbred goats were randomly divided into 3 groups based on first fortnight milk yield, and then adjusted to body weights to study the effect of fibrolytic enzyme supplementation on digestibility and milk production. Goats in the control group (C) were fed 500 g of concentrate supplement (CS) without exogenous fibrolytic enzymes (control; CG) or CS fortified with cellulase and xylanases @ of 4000 and 12500 (EG1) or 8000 and 18 750 IU/kg (EG2), respectively. CS was offered in two equal proportions just after milking at 7 and 17 h. After feeding CS, goats were fed 1200 g of wheat straw as roughage in two equal parts at 08.00 and 18.00 hours. Milk yield was studied for 3½ months. Milking was done by hand. Changes in body weight were also recorded. After a preliminary period of 60 days of feeding, a 7-day digestibility trial was conducted in two intervals with 5 animals from each group at a time. The increase in either wheat straw or NDF intake due to the enzyme mixture was only 3%. There was significant improvement (P < 0.05) in the diet digestibility of DM, OM, CP, NDF, ADF and total carbohydrates (TC) between the control and EG1 and EG2 goats. Improvements were greater (P < 0.05) in the latter group. Microbial protein (MBP) was estimated based on purine derivatives and creatinine excreted in spot urine samples. MBP increased about 10 and 15% in EG1 and EG2, but these values were statistically invalid. Phenomenally milk yield, fat and SNF were significantly (P < 0.001) changed with progression of lactation. On a temporal basis, fortnightly changes in FCM yield of this study could be grouped as 1 month each of first and last and 1½ of middle phase of lactation. Repeated measure analysis showed 180 to 260 mL/day of higher FCM and 16 to 20 g/day of higher SNF yield (P < 0.001) in EG2 than control or even EG1 during 5 to 7th fortnight. However, no significant impact (P > 0.05) was noticed on TF. Feed intake, g/kg FCM yield was also 7% less in EG2 than either CG or EG1. The study concluded that apart from increased digestibility, fortification of CS with cellulase and xylanases enzymes improved FCM yield in the last quarter of lactation in goats, and improved body weights by 5% (P > 0.05). While the digestibility of the diet was higher in EG1 and EG2, the impact on FCM and SNF yield was noticed only on EG2. Our study indicated that CS of lactating goats may be fortified with 8000 and 18 500 IU/kg CS in the last quarter of lactation. [source]


Short-range dispersal of recently emerged males and females of Bactrocera tryoni (Froggatt) (Diptera: Tephritidae) monitored by sticky sphere traps baited with protein and Lynfield traps baited with cue-lure

AUSTRALIAN JOURNAL OF ENTOMOLOGY, Issue 2 2007
Christopher Weldon
Abstract, Dispersal of immature male and female Queensland fruit fly, Bactrocera tryoni (Froggatt) (Diptera: Tephritidae), was assessed over a period of 1 week from a single release point on three separate occasions using an array of Lynfield traps baited with cue-lure and odouriferous yellow or black sticky spheres baited with food lure (protein autolysate). Lynfield traps recaptured males; yellow or black spheres recaptured both sexes in approximately equal proportions, although at a much lower rate. As a percentage of the recapture rate for males by Lynfield traps, the mean recapture rate for yellow spheres ranged from 1.0% to 7.5% for males and 0.7% to 4.0% for females, whereas the recapture rates for black spheres ranged from 0.4% to 3.6% and 0.6% to 1.8%, respectively. The rate of recapture of sterile male flies was greater than that of unsterilised flies; this may have been due to a faster maturation rate in sterile males or because a greater proportion of them remained within the trap array rather than dispersing. There was no significant trend in recapture rate with distance from the release point to the edge of the array (88 m), except in the case of females on sticky traps where no trend was detected between 19 and 88 m. These results lend support to assumptions made about the distribution of males and females with respect to the minimum breeding density of fruit fly propagules invading a fly-free zone, and the method chosen to distribute sterile B. tryoni for the sterile insect technique. [source]