Search Results - (Author, Cooperation:Moate)

1365-2494

Blackwell Publishing Journal Backfiles 1879-2005

Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition

The variation in the dietary cation–anion difference (DCAD) and the urinary pH of dairy cows was examined over the year 1996–97 in Victoria, south-eastern Australia. Mineral concentrations in the pasture and dairy cow milk production were also examined. Three farmlets (A, B and C) under different feeding and management systems were used for the purpose of the study. Feeding management was based on grazed grass with stocking rates of 1·4, 2·5 and 4·7 cows ha–1 for farmlets A, B and C respectively. Cows on farmlets B and C received more supplementary feed than those on the A farmlet.The urine of the cows in each herd was sampled for pH twice monthly, after morning milking. A sample of the feed on offer the previous day was collected and analysed for crude protein, in vitro dry-matter digestibility and macrominerals. Milk yields were recorded on the same day as urine sampling and weather data for the previous day were also collected.Pasture cation–anion difference was not greatly influenced by stocking rate or associated management practices, although mineral concentrations in pasture did vary. Urine pH was unaffected by changes in climate, management strategies (e.g. stocking rate), season and stage of lactation. Moreover, urine pH was also unaffected by changes in DCAD until the DCAD declined below approximately +15 mequiv. 100 g–1 for two consecutive sampling periods.It is concluded that when this threshold for DCAD (+15 mequiv. 100 g–1) is breached, even in late lactation, a decrease in urine pH occurs. In south-eastern Australia, the DCAD offered to non-lactating cows in the last 2 weeks of pregnancy, in spring-calving herds, on a pasture-based diet is nearly always above that regarded as optimum in other feeding systems.

Electronic Resource

1095-8649

Blackwell Publishing Journal Backfiles 1879-2005

Biology

The degree of similarity between the ‘pseudobranch type’ and ‘chloride type’ cells in the pseudobranch of bass (Dicentrachus labrax (L)), smelt (Osmerus esperlangus) and rainbow trout (Salmo gairdneri) was studied. The pseudobranch of bass and smelt contains two specialised cell types commonly known as ‘chloride type’ and ‘pseudobranch type’ cells, whereas rainbow trout only possess the latter type. ‘Pseudobranch type’ cells are characterised by the orderly arrangement of parallel tubules around their closely packed mitochondria. ‘Chloride type’ cells are identified by their highly branched tubular network, randomly distributed mitochondria, and the presence of an apical pit. Although ultra-structural changes were noted under osmotic stress, the ‘chloride type’ and ‘pseudobranch type’ cells remained distinguishable from each other and gave no reason to suggest that they were different forms of the same cell type. It was concluded that the two are distinct cell types, performing different, though possibly related, functions.

Electronic Resource

1095-8649

Blackwell Publishing Journal Backfiles 1879-2005

Biology

The polarization of ultrastructural ciliary bundles from hair cells in the inner ear of the sea scorpion Taurulus bubalis was studied using a scanning electron microscope, revealing arrays of ciliary bundles with diverse orientations on each of the sensory epithelia. Members of this order are known to produce sound, though results of this study show no significant variation from the standard receptor patterns found in the hearing system of many silent marine teleosts. This is the first time that the ultrastructure of T. bubalis has been studied, and this work presents a new set of polarization patterns, which provide anatomical information important in understanding electrophysiological aspects of fish hearing from an ecological perspective.

Electronic Resource

1550-7408

Blackwell Publishing Journal Backfiles 1879-2005

Biology

. DNA fragments homologous to P-type cation translocating ATPase genes were identified in Trichomonas vaginalis by polymerase chain reaction (PCR) amplification. The genomic locus corresponding to one PCR fragment, TVCA1, contains a 3,055 base-pair open reading frame encoding a 108,162 dalton protein composed of 981 amino acids. TVCA1 lacks introns, is present in a single copy, and is expressed as a 3.1 kb transcript with short 5’and 3’untranslated regions. Separate primer extension experiments map the 5’end of the TVCA1 transcript to 12 and 16 nucleotide bases (nt) upstream of the methionine initiation codon. The message polyadenylation site is located 62 nt downstream of the protein termination codon at a CA dinucleotide. The TVCA1 protein sequence shares 57-58% similarity with rabbit, schistosome, trypanosome and malarial sarcoplasmic-endoplasmic reticulum calcium (SERCA) pumps, and significantly lower similarity with plasma membrane calcium pumps and cation translocating ATPases of other ion specificities. Structural and functional domains identified in P-type ATPases as well as 61/68 residues specifically implicated in SERCA pump activity are conserved in TVCA1. However, TVCA1 lacks binding sites for phospholamban regulation, thapsigargin inhibition and the calmodulin dependent protein kinase site phosphorylation present in other SERCA pumps.

Electronic Resource

1432-1793

Springer Online Journal Archives 1860-2000

Biology

Abstract Following a 14 d exposure to sublethal concentrations of copper [0 (= control), 50, 100, 200, 300, 500 μg l−1] in a static laboratory system, Gills 5 and 8 of the common shore crab Carcinus maenas (L.) were removed and examined for damage by transmission electron microscopy. In this species, the anterior gills (1 to 6) are primarily respiratory in function, while the posterior gills (7 to 9) have an additional osmoregulatory role, with the respiratory epithelia being restricted to areas proximal to the marginal canal. The first signs of damage (epithelial hyperplasia, necrosis, vacuolation, haemocyte infiltration) occurred at 100 μg Cu l−1, but only in the respiratory gill (5) and only in areas close to the marginal canal. At 200 to 500 μg Cu l−1, these ultrastructural changes spread progressively throughout the lamellae of the respiratory gill. No damage was observed in the osmoregulatory gill (8) until 300 μg Cu l−1, and structural disruption, similar to that seen in the respiratory gill at 100 μg Cu l−1, was not observed until exposure to 500 μg Cu l−1; lipofuscin granule formation was seen in the osmoregulatory gill following exposure to 300 and 500 μg Cu l−1. The physiological implications of the differing sensitivities of the two gill types to water-borne copper are discussed.

Electronic Resource

1615-6102

Allergens ; Allergy ; Betula pendula ; Immunolabelling ; Pollen grains ; Tapetum

Springer Online Journal Archives 1860-2000

Biology

Summary Although intact pollen grains are assumed to be the primary carrier of pollen allergens, specific immunoreactive components have been found in other aerosol fractions, e.g., starch grains and remains of tapetal cells Cryo-scanning-electron-microscopy results demonstrate the presence of a clear network of strands connecting the tapetum with the microspores. The distribution of protein in tapetal orbicules, pollen wall, and pollen cytoplasm was tested by histochemical stains for light microscopy and transmission electron microscopy. The protein is mainly localized at the apertures and starch grains in the cytoplasm of pollen and in the core and on the surface of tapetal orbicules. Monoclonal antibodies Bv-10, BIP3, and BIP4 have been used to locate the cellular sites of pollen and tapetal allergens inBetula pendula (syn.B. verrucosa). The application of rapid-freeze fixation prevented relocation of allergens from their native sites. The allergens are predominantly found in the starch grains and to lesser extent in the exine. We also tested interactions between mature birch pollen and human fluids: saliva, nostrils fluid, and eyes solution. The aim was to mimic more closely the in vivo situation during allergenic response. In all cases we observed several pollen grains that were burst and had released their cytoplasmic contents. In the nose the allergens are released from the pollen within minutes. In rhinitis, nasal pH is increased from the normal pH 6.0 to 8.0. When we used nasal fluid at pH 8.0, the number of ruptured pollen grains increased. The mechanism that might induce formation of small allergen-bearing particles from living plant cells is discussed.

Electronic Resource

article

2018

Primarbereich ; Sekundarbereich ; Alltagssprache ; Fremdsprachenunterricht ; Fachunterricht ; Fachsprache ; Praxisbezug

Babylonia, (2018) H. 2, S. 21-25, 1420-0007

English

Literaturangaben

Online

2021

Pädagogisches Handeln ; Interview ; Lehramtsstudent ; Lehrerausbildung ; Sprache ; Englischunterricht ; Berufliche Identität ; Universität ; Hochschullehrer ; Finnland

CEPS journal, Bd. 11 (2021) H. 3, S. 9-33, 2232-2647

English

2018-02-17

Wiley-Blackwell

1354-1013

1365-2486

Biology

Energy, Environment Protection, Nuclear Power Engineering

Geography