bluuebunny/crossref_metadata_2025_split huggingface dataset:
CD4+ CD25+ transforming growth factor-β-producing T cells are present in the lung in murine tuberculosis and may regulate the host inflammatory response
Authors: Mason C M , Porretta E , Zhang P , Nelson S 
Published: August 2010

SummaryCD4+ CD25+ regulatory T cells produce the anti-inflammatory cytokines transforming growth factor (TGF)-β or interleukin (IL)-10. Regulatory T cells have been recognized to suppress autoimmunity and promote self-tolerance. These cells may also facilitate pathogen persistence by down-regulating the host defence response during infection with Mycobacterium tuberculosis. We evaluated TGF-β+ and IL-10+ lung CD4+ CD25+ T cells in a murine model of M. tuberculosis. BALB/c mice were infected with ∼50 colony-forming units of M. tuberculosis H37Rv intratracheally. At serial times post-infection, lung cells were analysed for surface marker expression (CD3, CD4, CD25) and intracellular IL-10, TGF-β, and interferon (IFN)-γ production (following stimulation in vitro with anti-CD3 and anti-CD28 antibodies). CD4+ lung lymphocytes were also selected positively after lung digestion, and stimulated in vitro for 48 h with anti-CD3 and anti-CD28 antibodies in the absence and presence of anti-TGF-β antibody, anti-IL-10 antibody or rmTGF-β soluble receptor II/human Fc chimera (TGFβsrII). Supernatants were assayed for elicited IFN-γ and IL-2. Fluorescence activated cell sorter analyses showed that TGF-β- and IL-10-producing CD4+ CD25+ T cells are present in the lungs of infected mice. Neutralization of TGF-β and IL-10 each resulted in increases in elicited IFN-γ, with the greatest effect seen when TGFβsrII was used. Elicited IL-2 was not affected significantly by TGF-β neutralization. These results confirm the presence of CD4+ CD25+ TGF-β+ T cells in murine pulmonary tuberculosis, and support the possibility that TGF-β may contribute to down-regulation of the host response.
Spleen lymphocyte function modulated by a cocoa-enriched diet
Authors: Ramiro-Puig E , Pérez-Cano F J , Ramírez-Santana C , Castellote C , Izquierdo-Pulido M , Permanyer J , Franch A , Castell M 
Published: August 2010

SummaryPrevious studies have shown the down-regulating in vitro effect of cocoa flavonoids on lymphocyte and macrophage activation. In the present paper, we report the capacity of a long-term rich cocoa diet to modulate macrophage cytokine secretion and lymphocyte function in young rats. Weaned rats received natural cocoa (4% or 10% food intake), containing 32 mg flavonoids/g, for 3 weeks. Spleen immune function was then evaluated through the analysis of lymphocyte composition, their proliferative response and their ability to secrete cytokines and Ig. In addition, the status of activated peritoneal macrophages was established through tumour necrosis factor (TNF)-α secretion. The richest cocoa diet (10%) caused a reduction of TNF-α secretion by peritoneal macrophages showing anti-inflammatory activity. Similarly, although a 10% cocoa diet increased lymphocyte proliferation rate, it down-regulated T helper 2 (Th2)-related cytokines and decreased Ig secretion. These changes were accompanied by an increase in spleen B cell proportion and a decrease in Th cell percentage. In summary, these results demonstrate the functional activity of a cocoa-high dosage in down-regulating the immune response that might be beneficial in hypersensitivity and autoimmunity.
Coupled diffusion and oxidation of ferrous iron in soils. II. A model of the diffusion and reaction of O2, Fe2+, H+ and HCO3− in soils and a sensitivity analysis of the model
Authors: KIRK G. J. D. , AHMAD A. R. , NYE P. H. 
Published: August 2010

SUMMARYKinetic equations are developed for a system in which a column of reduced soil is exposed to oxygen at one end. The equations are combined in a simulation model in which they are solved by finite‐difference methods. The model predicts the consequent diffusion of oxygen into the column; the diffusion of ferrous iron towards the oxidation zone; the rate of formation and concentration profile of the ferric hydroxide formed; and the diffusion by acid‐base transfer of the acidity produced in the oxidation reaction.A sensitivity analysis of the model, in which runs were made for a wide range of input parameters, showed that for most combinations of parameters, in water‐saturated soil, substantial amounts of iron are transferred towards the air‐exposed surface, leading to a well‐defined zone of ferric hydroxide accumulation. The profile of total iron in this zone is often banded. The pH in the zone falls by at least two units. A small amount of air‐filled pore space increases the depth of the oxidation front dramatically. The model indicates that coupled iron oxidation and diffusion reactions, which are very widespread in natural soils, may be understood quantitatively.
Measurement of electrostatic and site‐specific associations of alkali metal cations with humic acid
Authors: BONN B. A. , FISH W. 
Published: August 2010

SUMMARYA discontinuous acidimetric titration method incorporating ultrafiltration was developed to measure the association of a soil humic acid with Li+ t, Na+ and K+ (pH 3 to 8). In addition, possible site‐specific binding of these alkali metal cations was investigated using desorption experiments at pH 1. Li, Na and K cations behaved equivalently in the titrations and the amounts of these cations associated with the humic acid was measurable at all pH values between 3 and 8. Up to 90% of the total alkali metal cation was humate‐associated at pH 8. The absolute amount of humic‐associated cation did not depend on the alkali metal cation concentration, but rather on the solution alkalinity. In addition, the net charge of the humate polyanion made a negligible contribution to the electroneutrality of the bulk solution under all conditions. These results are consistent with a diffuse layer model of hydrated humic acid in which the alkali metal cations neutralize the humic charge. The association of Na+ andK+ with humic acid at pH 1 was successfully described by a Langmuir adsorption model. The number of sites per g of humic acid was very small, and greater for K+ than for Nat. Lithium cations exhibited no detectable humic association at pH 1. These differences suggest that humic acids may have a small number of specific binding sites for which the size of the hydrated cation is important.
Agrochemical controlled‐release and transport in the soil profile: I. Model formulation and sensitivity analysis for bare soil under field conditions
Authors: FRIEDMAN S. P. 
Published: August 2010

SummaryThe controlled release of agrochemicals from capsules, uniformly distributed in the soil, and their spread in the soil profile by diffusion and convection, coupled with first‐order degradation, are studied theoretically. This transient transport is formulated mathematically as an approximate description of two simultaneous processes: (1) local release from the capsule, described as taking place in a confined, spherical soil domain, with a quasi‐steady‐state diffusional spread in each time step and (2) the vertical spread of the released material in the soil profile, described by the convection‐dispersion equation including a source term for the solute transport, coupled with the Richards’ equation for the water flow. These processes of release, spread and degradation are simulated for realistic field conditions to study the effects of management practices and environmental conditions on the release rate. For a given amount of chemical per unit area, the rate of release increases with increasing number of capsules and with increasing depth of incorporation. Increasing irrigation intensity also enhances the release rate, as well as increasing the time interval between irrigations for the same seasonal amount of water applied. Under a given irrigation regime and incorporation practice, the rate of release increases progressively from coarse to fine‐textured soils. The amount of released agrochemical remaining in the target zone after a certain time is compared with the amounts of a similar non‐encapsulated agrochemical and of an inert tracer retained in the soil. The encapsulated material always persists longer, to an extent depending on the above‐mentioned conditions.
Complexation of Cu2+ and Pb2+ by peat and humic acid
Authors: LOGAN E. M. , PULFORD I. D. , COOK G. T. , MACKENZIE A B. 
Published: August 2010

SummaryThe binding of metal to humic substances is problematical. The approaches for studying metal binding to organic matter are briefly reviewed. Ion‐selective electrodes (Cu2+ and Pb2+) were used to measure metal complexation by a whole peat and an extracted humic acid (HA) fraction. Scatchard plots and calculation of incremental formation constants were used to obtain values for the binding constants for the metals onto both peat and HA. Both the peat and the humic acid had a larger maximum binding capacity for Pb2+ than for Cu2+ (e.g. at pH = 5 HA gave 0·188 mmol Cu2+ g−1 and 0·564 mmol Pb2+ g−1: peat gave 0·111 mmol Cu2+ g−1 and 0·391 mmol Pb2+ g−1). Overall, the humic acid had a larger metal binding capacity, suggesting that extraction caused conformational or chemical changes. The binding constants (K1) for Cu2+ increased with increasing pH in both peat and humic acid, and were larger in the peat at any given pH (e.g. at pH = 5 HA gave log K1= 2·63, and peat gave log K1= 4·47 for Cu2+). The values for Pb2+ showed little change with pH or between peat and humic acid (e.g. at pH = 5 HA gave log K1= 3·03 and peat gave log K1= 3·00 for Pb2+). In the peat, Cu2+ may be more able to bind in a 2:1 stoichiometric arrangement, resulting in greater stability but smaller binding capacity, whereas Pb2+ binds predominantly in a 1:1 arrangement, with more metal being bound less strongly. Whole peat is considered to be more appropriate than an extracted humic acid fraction for the study of heavy metal binding in organic soils, as this is the material with which metals introduced into an organic soil would interact under natural conditions.
Data transformations between soil texture schemes
Authors: ROUSSEVA S. S. 
Published: August 2010

SummaryVarious soil texture schemes are in current use. These differ in the size ranges of their particle fractions. There is a need to establish simple methods to correlate these conventional schemes. Therefore I have defined closed‐form exponential and power law functions to fit models to cumulative particle‐size distribution data. I have tested the functions for their suitability (i) to represent cumulative particle‐size distribution curves and (ii) to transfer data between distributions that differ in the size ranges of the particle fractions. I found that closed‐form exponential functions adequately represent the cumulative particle‐size distributions of fine‐textured soils (clay, silty clay, silty clay loam, clay loam, silt loam and loam texture), whilst closed‐form power functions better describe the cumulative particle‐size distributions of coarse‐textured soils (sand, loamy sand, sandy loam, sandy clay and sandy clay loam texture). The functions defined are found to be suitable to transfer data between different texture schemes. The use of this approach is illustrated by examples of data transformations between three widely used soil texture schemes: ISSS, Katschinski's and USDA.
Constitutive and inducible defensive traits in co‐occurring marine snails distributed across a vertical rocky intertidal gradient
Authors: Bourdeau Paul E. 
Published: August 2010

Summary 1. Among‐species differences in the expression of constitutive and plastic traits may shape species distributions within a community. For many systems, the relationships among individual species’ phenotypes, particularly morphological plasticity, and performance and distribution are poorly understood. 2. I tested whether three co‐occurring species of marine snails in the genus Nucella differed in their constitutive and inducible defences against crabs, in terms of growth and shell architectural defence. I also tested whether among‐species trait differences were associated with interspecific differences in antipredator performance (resistance to crushing) and distributions along a vertical tidal emersion gradient on rocky shores where the snails co‐occur. 3. Species distributed lower on the shore and thus exposed to crabs for longer periods of time exhibited higher constitutive growth rates than the upper‐shore species. Lower‐shore species also exhibited greater inducible reductions in somatic growth and increases in shell thickening than the upper‐shore species. Plastic alterations of the scaling relationship between shell‐thickness and somatic growth (i.e. greater shell mass per body mass) enabled the two lower‐shore species to produce stronger, more crab‐resistant shells in the presence of crabs than their upper‐shore congener. 4. Results suggest that species‐specific differences in both constitutive and inducible shell defence and growth reflect growth/mortality tradeoffs that are associated with species’ vertical distributions along a predation risk gradient. Thus, adaptive differences in inducible morphological defenses should be considered along with more traditionally studied traits such as behaviour and constitutive morphological defenses, when examining traits that influence patterns of species distribution along environmental gradients.
Transgene‐mediated suppression of dengue viruses in the salivary glands of the yellow fever mosquito, Aedes aegypti
Authors: Mathur G. , Sanchez‐Vargas I. , Alvarez D. , Olson K. E. , Marinotti O. , James A. A. 
Published: August 2010

AbstractControlled sex‐, stage‐ and tissue‐specific expression of antipathogen effector molecules is important for genetic engineering strategies to control mosquito‐borne diseases. Adult female salivary glands are involved in pathogen transmission to human hosts and are target sites for expression of antipathogen effector molecules. The Aedes aegypti 30K a and 30K b genes are expressed exclusively in adult female salivary glands and are transcribed divergently from start sites separated by 263 nucleotides. The intergenic, 5′‐ and 3′‐end untranslated regions of both genes are sufficient to express simultaneously two different transgene products in the distal‐lateral lobes of the female salivary glands. An antidengue effector gene, membranes no protein (Mnp), driven by the 30K b promoter, expresses an inverted‐repeat RNA with sequences derived from the premembrane protein‐encoding region of the dengue virus serotype 2 genome and reduces significantly the prevalence and mean intensities of viral infection in mosquito salivary glands and saliva.
Partial migration in tropical birds: the frontier of movement ecology
Authors: Sekercioglu Cagan H. 
Published: August 2010

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A. E. Jahn, D. J. Levey, J. A. Hostetler & A. M. Mamani (2010) Determinants of partial bird migration in the Amazon Basin. Journal of Animal Ecology, 79, 983–992. Partial migration, in which only some individuals of a species migrate, might be central to the evolution of migratory behaviour and is likely to represent an evolutionary transition between sedentariness and complete migration. In one of the few detailed, individual‐based migration studies of tropical birds, Jahn et al. study the partial migration system of a South American bird species for the first time. Food limitation forces the large adult males and small, young females to migrate, contrary to the expectations of the body size and dominance hypotheses. This study confirms the importance of food variability as the primary driver of migratory behaviour. There is urgent need for similar studies on the movement ecology of understudied tropical bird species, whose diversity of migratory behaviour can shed light on the evolution of bird migration.
The development of SCORM‐conformant learning content based on the learning cycle using participatory design
Authors: Su C.Y. , Chiu C.H. , Wang T.I. 
Published: August 2010

AbstractThis study incorporates the 5E learning cycle strategy to design and develop Sharable Content Object Reference Model‐conformant materials for elementary science education. The 5E learning cycle that supports the constructivist approach has been widely applied in science education. The strategy consists of five phases: engagement, exploration, explanation, elaboration and evaluation. It has potential value for creating effective science e‐learning materials. This study implemented the participatory design (PD) method to investigate the possibility of applying the 5E model to science e‐learning materials. PD is an approach that understands knowledge by doing and focuses on collaborating with the intended users rather than designing ‘for’ them. In this study, researchers, designers and elementary science teachers cooperated at all stages of the design process (including explanation, analysis and decision making). The issues to be dealt with in this study included instructional designs based on the 5E model, techniques or specifications of e‐learning, learning objects, metadata and procedures. The results of this study provided concrete recommendations for how to incorporate the 5E learning cycle and how to develop effective e‐learning materials for elementary science instruction.
Observations on the facial sclerite of the larva of Papilio demoleus L. (Lepidoptera: Papilionidae)
Authors: Zaka‐ur‐Rab Mohammed 
Published: August 2010

SYNOPSISThe facial sclerite of the larva of Papilio demoleus is described and details of the musculature are given. A new interpretation of some of the facial structures is suggested.
Note on gregarious behaviour exhibited by Phymateus aegrotus Gerstaecker (Orthoptera: Acrididae)
Authors: Roffey J. 
Published: August 2010

SYNOPSISAn account is given of gregarious behaviour shown by groups of hoppers of Phymateus aegrotus found in a valley in the Northern Region of the Somali Republic, and their feeding habits are described. Reasons are given for the wide range of instars found in the groups.
Nocturnal flight activity of sylvan Culicidae and Tabanidae (Diptera) as indicated by light‐traps: a further study
Authors: Corbet Philip S. 
Published: August 2010

SYNOPSISObservations made by means of light traps operated at seven different levels in and above the canopy of the Zika Forest, Uganda are described, and the nocturnal flight activity of 41 species of mosquitoes and 7 species of Tabanids is discussed.
Inbreeding and arrhenotoky in the ambrosia beetle Xyleborus compactus (Eichh.) (Coleoptera: Scolytidae)
Authors: Entwistle P. F. 
Published: August 2010

SYNOPSISAn account is given of the composition of populations in galleries formed by Xyleborus compactus in stems of coffee and cocoa in Western Nigeria. The incidence of arrhenotokous parthenogenesis and of a high degree of inbreeding is described and the possible significance of inbreeding in regard to variation in morphology and behaviour is discussed.
The possible rôle of haemoglobin in Anisops and Buenoa (Hemiptera: Notonectidae)
Authors: Miller P. L. 
Published: August 2010

SynopsisAn account is given of the abdominal respiratory structures in Anisops pellucens and A. debilis (Notonectids common in small bodies of water in Uganda), which contain haemoglobin in specialised cells in the abdomen. The dive characteristics of these water bugs are described and compared with those of species that lack haemoglobin. Modifications of the dive brought about by the introduction of carbon monoxide are examined. The possible adaptive significance of the invasion of the midwater zone and the adoption of a pelagic existence by the Anisopinae is discussed.
The biology and immature stages of two species of Medetera (Diptera: Dolichopodidae) associated with the bark beetle Scolytus scolytus (F.)
Authors: Beaver R. A. 
Published: August 2010

SYNOPSISAn account is given of the seasonal history of Medetera nitida and M. impigra, the larvae of which are predators of the bark beetle Scolytus scolytus, and observations on oviposition and larval feeding are recorded. The immature stages are described and compared.
Nocturnal flight cycle in the males of African doryline ants (Hymenoptera: Formicidae)
Authors: Haddow A. J. , Yarrow I. H. H. , Lancaster G. A. , Corbet Philip S. 
Published: August 2010

SYNOPSISAn account is given of light‐trap catches of ants of the genus Dorylus at two localities in Uganda.
The spiracular gill of the fly, Antocha bifida, as seen with the scanning electron microscope
Authors: Hinton H. E. 
Published: August 2010

SYNOPSISThe structure and function of the plastron‐bearing spiracular gills of the pupa of a tipulid fly, Antocha bifida, are described. The structure of the plastron has been examined with a scanning electron microscope. The significance of the two tissue reservoirs of the gill is discussed.
The mating plug in anopheline mosquitoes
Authors: Giglioli M. E. C. , Mason G. F. 
Published: August 2010

SYNOPSISAn account is given of the formation of the mating plug in the atrium of newly mated females of Anopheles from genital secretions of the male and female. The function of these secretions, and of the mating plug, is discussed.
Observations on biology in the genus Caryedon Schönherr (Coleoptera: Bruchidae) in Northern Nigeria, with a list of associated parasitic Hymenoptera
Authors: Prevett P. F. 
Published: August 2010

SYNOPSISObservations on the biology of the eleven species of Caryedon found in Northern Nigeria are recorded. A list of the parasitic Hymenoptera associated with Caryedon infestations is included.
Aspects of the biology of Microvelia macgregori Kirkaldy (Heteroptera: Veliidae)
Authors: Don A. W. 
Published: August 2010

SynopsisAn account is given of oviposition, the development of the egg, the postnatal moult and the duration of the larval instars in Microvelia macgregori.The phenomenon of alary polymorphism is discussed in the light of prevailing theories.
The incidence of diapause in Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae) in the Gezira Scheme, Sudan
Authors: Khalifa A. 
Published: August 2010

SynopsisAn account is given of the occurrence of diapause in Pectinophora gossypiella in the Gezira Scheme, Sudan. The incidence and duration of diapause throughout two successive cotton seasons are discussed.
Further data on the oviposition by the genus Stylogaster Macquart (Diptera: Conopidae, Stylogasterinae) upon adult calyptrate Diptera associated with ants and animal dung
Authors: Smith Kenneth G. V. 
Published: August 2010

SynopsisEggs of Stylogaster are recorded for the first time on adults of the calyptrate genera Bengalia, Tricyclea and Hemigymnochaeta (Calliphoridae), and Sromoxys, Bdellia, Phaonia, Emmesomyia and Helina (Muscidae). The connection of the hosts with Stylogaster, through their association with ants or animal dung, is discussed. It is suggested that a record in the literature, of Stylogaster reared from a puparium of Glossina morsitans is in error.
Aerial dispersal of some British Psocoptera, as indicated by suction trap catches
Authors: New T. R. 
Published: August 2010

SynopsisAn account is given of the numbers of Psocoptera taken in suction traps at Silwood Park, Berkshire, over seven seasons. The flight activity of several species is discussed in relation to their bionomics, and flight muscle autolysis and alary polymorphism are briefly discussed.
External parasitisation and blood‐feeding by the lepidopterous larvaEpipyrops anomalaWestwood
Authors: Marshall A. T. 
Published: August 2010

SynopsisThe life habits ofEpipyrops anomalaare described with particular reference to cocoon formation and the manner in which the larva lives as an external parasite ofFulgora candelaria.A description of feeding and of the structure of the alimentary canal is also given.