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Selected AbstractsChanges in vascularity and blood volume as a result of photodynamic therapy can be assessed with power Doppler ultrasonographyLASERS IN SURGERY AND MEDICINE, Issue 3 2006DECVDI, Stefanie Ohlerth Dr. Med.Vet. Abstract Background and Objectives One principal mechanism of photodynamic therapy (PDT) in tumors is destruction of tumor-associated vasculature. In the present study, the vascular effects of PDT in tumors were investigated with power Doppler ultrasonography. Materials and Methods Seven cutaneous squamous cell carcinomas in cats were treated. Tumors were examined via power Doppler ultrasonography before, 5 minutes, 1 hour, and 24 hours after PDT. Images were digitized for computer-aided assessment of vascularity and blood volume. Results Mean baseline tumor vascularity and blood volume were moderate. During PDT, a significant decrease in vascularity and blood volume was noted. Lowest values were found 24 hours after PDT. Conclusions Power Doppler ultrasonography represents a non-invasive modality to successfully monitor the vascular effects and thus, treatment efficacy, of PDT. Lasers Surg. Med. 38:229,234, 2006. © 2006 Wiley-Liss, Inc. [source] The birth process initiates an acute phase reaction in the fetus-newborn infantACTA PAEDIATRICA, Issue 9 2000G Marchini Our goal was to investigate whether the normal birth process stimulated an acute phase response in healthy infants with physiological changes in the circulating levels of acute phase cytokines and acute phase proteins. We also monitored body temperature, body weight and behavioural state in order to investigate if clinical signs of acute phase reaction were present. We made cross-sectional measurements of interleukin-1,, interleukin-6, C-reactive protein, serum amyloid A, procalcitonin, prealbumin, body weight, body temperature and the duration of the sleeping period during the first four postnatal days. We found an increase in interleukin-6 (p < 0.001) during the first day, followed by an increase in C-reactive protein, serum amyloid A and procalcitonin on the second postnatal day (p < 0.01). The level of prealbumin fell after birth and reached its lowest value at 3 d of age (p < 0,001). Interleukin-l p remained unchanged. The duration of the sleeping period was longer during the first day (p < 0.01). There was an increase in body temperature during the first day (p < 0.01). Maximal weight loss was during the first 2 d. Conclusions: The normal birth process and extra-uterine adaptation stimulates an acute phase reaction in the newborn infant with a release of interleukin-6 and acute phase proteins and a depression of prealbumin. This reaction, as the body's first line inflammatory defence system, probably affects the infant's behaviour, nutritional state as well as the regulation of body temperature. [source] Large-scale distribution and activity patterns of an extremely low-light-adapted population of green sulfur bacteria in the Black SeaENVIRONMENTAL MICROBIOLOGY, Issue 5 2010Evelyn Marschall Summary The Black Sea chemocline represents the largest extant habitat of anoxygenic phototrophic bacteria and harbours a monospecific population of Chlorobium phylotype BS-1. High-sensitivity measurements of underwater irradiance and sulfide revealed that the optical properties of the overlying water column were similar across the Black Sea basin, whereas the vertical profiles of sulfide varied strongly between sampling sites and caused a dome-shaped three-dimensional distribution of the green sulfur bacteria. In the centres of the western and eastern basins the population of BS-1 reached upward to depths of 80 and 95 m, respectively, but were detected only at 145 m depth close to the shelf. Using highly concentrated chemocline samples from the centres of the western and eastern basins, the cells were found to be capable of anoxygenic photosynthesis under in situ light conditions and exhibited a photosynthesis,irradiance curve similar to low-light-adapted laboratory cultures of Chlorobium BS-1. Application of a highly specific RT-qPCR method which targets the internal transcribed spacer (ITS) region of the rrn operon of BS-1 demonstrated that only cells at the central station are physiologically active in contrast to those at the Black Sea periphery. Based on the detection of ITS-DNA sequences in the flocculent surface layer of deep-sea sediments across the Black Sea, the population of BS-1 has occupied the major part of the basin for the last decade. The continued presence of intact but non-growing BS-1 cells at the periphery of the Black Sea indicates that the cells can survive long-distant transport and exhibit unusually low maintenance energy requirements. According to laboratory measurements, Chlorobium BS-1 has a maintenance energy requirement of ,1.6,4.9·10,15 kJ cell,1 day,1 which is the lowest value determined for any bacterial culture so far. Chlorobium BS-1 thus is particularly well adapted to survival under the extreme low-light conditions of the Black Sea, and can be used as a laboratory model to elucidate general cellular mechanisms of long-term starvation survival. Because of its adaptation to extreme low-light marine environments, Chlorobium BS-1 also represents a suitable indicator for palaeoceanography studies of deep photic zone anoxia in ancient oceans. [source] Seasonal variation in rates of methane production from peat of various botanical origins: effects of temperature and substrate qualityFEMS MICROBIOLOGY ECOLOGY, Issue 3 2000Inger Bergman Abstract The methane produced in peat soils can vary over the growing season due to variations in the supply of available substrate, the activity of the microbial community or changes in temperature. Our aim was to study how these factors regulate the methane production over the season from five different peat types of different botanical origin. Peat samples were collected on seven occasions between June and September. After each sampling, the peat soils were incubated at five different temperatures (7, 10, 15, 20 and 25°C) without added substrate, or at 20°C with added substrate (glucose, or H2/CO2, or starch). Rates of methane production averaged over the season differed significantly (P<0.05, R2=0.76) among the five peat types, the minerotrophic lawn producing the highest rates, and the hummock peat producing the lowest. The seasonal average Q10 values for each plant community varied between 4.6 and 9.2, the highest value being associated with the ombrotrophic lawn and the lowest value with the mud-bottom plant community. For the unamended peat samples, the rates of methane production from each plant community varied significantly (P<0.05) over the season. This implies that the quality of organic matter, in combination with changes in temperature, explains the seasonal variation in methane production. However, addition of saturating amounts of glucose, H2/CO2 or starch at 20°C significantly reduced the seasonal variation (P<0.05) in methane production in peat from the minerotrophic lawn, wet carpet and mud-bottom plant communities. This suggests that substrate supply (e.g. root exudates) for the micro-organisms also varied over the season at these sites. Seasonal variation in methane production rates was apparent in peat from the hummock and ombrotrophic lawn plant communities even after addition of substrates, suggesting that the active biomass of the anaerobic microbial populations at these sites was regulated by other factors than the ones studied. [source] Effects of season, variety and botanical fractions on oxalate content of napiergrass (Pennisetum purpureum Schumach)GRASSLAND SCIENCE, Issue 4 2006M. M. Rahman Abstract Various tropical grasses sometimes contain oxalate in sufficient concentration as to induce calcium deficiency in grazing animals. Napiergrass (Pennisetum purpureum), a useful tropical grass for ruminants was examined for oxalate levels with regard to season, variety and botanical fractions. It was observed that oxalate content was significantly (P < 0.001) affected by the season with the highest value (3.77%) being associated with early summer samples and the lowest value (1.76%) with late autumn samples. Compared to a normal, non-dwarf variety, a dwarf variety exhibited a higher oxalate content but the difference was not statistically significant. With regard to the botanical fractions, oxalate content was significantly (P < 0.05) higher (2.78%) in leaf tissues compared to stem with leaf sheath (2.05%). In another experiment, a late, dwarf variety was re-grown four times to evaluate re-growth period effects on oxalate content during the early summer. Oxalate content increased gradually from the re-growth period 1 (6 June to 28 June) to re-growth period 3 (21 June to 12 July), and declined in re-growth period 4 (28 June to 19 July). Results suggest that when napiergrass is grown in early summer, it could achieve oxalate levels that are toxic to ruminants. [source] Serum HGF and TGF-,1 levels after right portal vein embolizationHEPATOLOGY RESEARCH, Issue 3 2010Hiromitsu Hayashi Aim:, The changes in the serum hepatocyte growth factor (HGF) and transforming growth factor (TGF)-beta1 levels after portal vein embolization (PVE), and their clinical significance, remain unclear and we aimed to assess their relationship. Methods:, The serum HGF and TGF-beta1 levels were prospectively measured in 22 patients before and 1, 3, 5, 7, and 14 day after right PVE. Computed tomographic volumetry was performed before and at a mean of 26 ± 4 days after right PVE. Results:, Three to four weeks after right PVE, the volume of embolized lobe significantly decreased from 704 ± 157 cm3 before PVE to 539 ± 168 cm3 after PVE (P < 0.001). In contrast, the volume of nonembolized lobe significantly increased from 426 ± 142 cm3 to 560 ± 165 cm3 (P < 0.001). The serum HGF level significantly increased on day 3 after PVE compared with the pretreatment level (P = 0.005), while the serum TGF-beta1 level significantly decreased and reached its lowest value on day 3 (P = 0.002). Using Pearson's correlation analysis, we found that the serum HGF and TGF-beta1 levels on day 14 negatively associated with the large hypertrophic response in the nonembolized lobe (HGF: r = ,0.490, P = 0.021; TGF-beta1: r = ,0.473, P = 0.026). Conclusions:, PVE induced an increase in the serum HGF level and reduced the serum TGF-beta1 level. Measurement of serum HGF and TGF-beta1 levels on day 14 after right PVE may be useful for assessment of the future liver hypertrophy in nonembolized lobe after right PVE. [source] Survey of methodologies for developing media screening values for ecological risk assessmentINTEGRATED ENVIRONMENTAL ASSESSMENT AND MANAGEMENT, Issue 4 2005Mace G. Barron Abstract This review evaluates the methodologies of 13 screening value (SV) compilations that have been commonly used in ecological risk assessment (ERA), including compilations from state and U.S. federal agencies, the Oak Ridge National Laboratory (ORNL), Canada, The Netherlands, and Australia. The majority of surfacewater SVs were primarily derived for the protection of aquatic organisms using 2 approaches: (1) a statistical assessment of toxicity values by species groupings, such as "ambient water quality criteria," or (2) extrapolation of a lowest observed adverse effect level determined from limited toxicity data using an uncertainty factor. Sediment SVs were primarily derived for the protection of benthic invertebrates using 2 approaches: (1) statistical interpretations of databases on the incidence of biological effects and chemical concentrations in sediment, or (2) values derived from equilibrium partitioning based on a surfacewater SV. Soil SVs were derived using a diversity of approaches and were usually based on the lowest value determined from soil toxicity to terrestrial plants or invertebrates and, less frequently, from modeled, incidental soil ingestion or chemical accumulation in terrestrial organisms. The various SV compilations and methodologies had varying levels of conservatism and were not consistent in the pathways and receptors considered in the SV derivation. Many SVs were derived from other compilations and were based on outdated values, or they relied on only older toxicity data. Risk assessors involved in ERA should carefully evaluate the technical basis of SVs and consider the uncertainty in any value used to determine the presence or absence of risk and the need for further assessment. [source] Optimal use of solar collectors for residential buildingsINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 11 2001Stig-Inge GustafssonArticle first published online: 5 JUN 200 Abstract Solar radiation is an abundant free resource which may be used in the form of solar heated water. This is achieved in solar collectors which, unfortunately, are expensive devices and, further, the warm water must be stored in accumulators,items which also cost money. This paper shows how we have optimized the situation for a block-of-flats in Sweden. In order to find this point we have used the minimum life-cycle cost (LCC) concept as a criterion. The best solution is therefore found when that cost finds its lowest value. It is also examined under which conditions solar collectors are part of the optimal solution and further it is calculated what happens if this optimal point is abandoned, i.e. how much will the LCC increase if other than optimal solutions are chosen. LCC optimization for multi-family buildings almost always results in a heating system with low operating costs such as district heating or dual-fuel systems where a heat pump takes care of the base load and an oil boiler the peak. The installation cost must, however, be kept to a reasonable level. Expensive solar panel systems are therefore normally avoided if the lowest LCC shall be reached, at least for Swedish conditions. This is so even if the solar system has a very low operating cost. For buildings where the only alternative energy source is electricity, solar collectors seem to be on the rim of profitability, i.e. for an energy price of about 0.6 SEK kWh,1. Copyright © 2001 John Wiley & Sons, Ltd. [source] Influence of nutrients on proteinase A activity in draft beer during fermentationINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 6 2010Xin Hao Summary With the increase of ,-amino nitrogen concentrations from 90 to 230 mg L,1, proteinase A (PrA) in wort fermentations was showing a downward trend while higher alcohols contents a U-shaped one. The level of 210 mg L,1 of ,-amino nitrogen supplement, at which wort fermentation exhibited a low PrA activity and a level of higher alcohols below the industrial norm (90 mg L,1), was used as the optimised ,-amino nitrogen concentration for further exploring the effect of biotin levels on PrA activity. In the biotin range of 0,65 ,g L,1, PrA activity registered the lowest value when biotin level was at 50 ,g L,1. Medium with 210 mg L,1 of ,-amino nitrogen and 50 ,g L,1 of biotin was therefore adopted for investigating influences of inorganic salt Fe2(SO4)3, KH2PO4, ZnSO4 and MgSO4 on PrA production. It was shown that Fe2(SO4)3 and KH2PO4 had significant influence on PrA production while ZnSO4 and MgSO4 did not. Based on above findings, an optimised set of nutritive elements was determined and used in fermentation. The results indicated that the activity of PrA reduced by 60% without noticeably effects of the fermentation performance and beer flavour. [source] Some aspects of the biology of the stargazer mountain catfish, Amphilius uranoscopus (pfeffer); (Siluriformes: Amphiliidae) indigenous to Kenya streamsAFRICAN JOURNAL OF ECOLOGY, Issue 4 2009Charles C. Ngugi Abstract A study on some biological parameters of the mountain catfish, Amphilius uranoscopus Pfeffer 1889 (Silurifomes: Amphiliidae), was carried out in the Thego stream on the slopes of Mount Kenya from February to December 2002. Physical and chemical profiles of the Thego show that the water quality parameters is typical of high altitude streams with temperatures rarely exceeding 18°C, DO ranging from 7.9 to 8.2 mg l,1 and relatively high conductivity (97,137 ,S cm,1) typical of perturbed lotic environments. A total of 1010 fish were caught by an electro-fisher, with sizes ranging between 8 and 24 cm fork length. The population structure had a unimodal distribution with maxima at 14,16 cm. The length,weight relationship showed relatively narrow range in the slope ranging from 2.61 in April to 2.98 in February 2002, thereby suggesting isometric growth pattern. The fitted growth pattern of A. uranoscopus showed an asymptotic length (L,) of 28.5 cm and a growth curvature (K) of 0.56 year,1 resulting in an estimated natural mortality coefficient (M) of 0.90 year,1. The Fulton's condition factor (K) was also relatively stable with a peak in April (0.92 ± 0.21) and lowest value in June (0.86 ± 0.10). As A. uranoscopus is not under commercial exploitation, the seemingly depressed population is possibly attributed to the introduced exotic rainbow trout that heavily predates on the species and environmental perturbations arising from changes in land use. The implications of such changes on A. uranoscopus are discussed. Résumé Une étude de certains paramètres du poisson-chat de montagne Amphilius uranoscopus Pfeffer 1889 (Silurifomes: Amphiliidae) a été réalisée dans le courant du Thego, sur les pentes du mont Kenya entre février et décembre 2002. Le profil physique et chimique du Thego montre que les paramètres de la qualité de l'eau sont typiques des cours d'eau de haute altitude, avec une température qui dépasse rarement 18°C, un OD qui varie de 7,9 à 8,2 mg/l, et une conductivité relativement haute (87 à 137 ,S/cm) typique d'environnements lotiques perturbés. Au total, 1 010 poissons ont été capturés au moyen d'une canne électrique, d'une taille allant de 8 à 24 cm de longueur à la fourche. La structure de la population avait une distribution unimodale avec des maxima de 14,16 cm. La relation longueur/poids présente une variation relativement étroite dans la pente, allant de 2,61 en avril à 2,98 en février 2002, ce qui suggère un schéma de croissance isométrique. Le schéma de croissance intégré d'A. uranoscopus montre une longueur asymptotique (L,) de 28,5 cm et une courbure de croissance (K) de 0,56/an, résultant en un coefficient de mortalité naturelle estimé (M) de 0,90/an. Le facteur de condition de Fulton (K) était aussi relativement stable, avec un pic en avril (0,92 ± 0,21) et la valeur la plus basse en juin (0,86 ± 0,10). Puisque A. uranoscopus ne fait pas l'objet d'une exploitation commerciale, la dépression apparente de la population doit peut-être être attribuée à la truite arc-en-ciel, espèce exotique introduite qui se nourrit abondamment de l'espèce, et à des perturbations environnementales provoquées par des changements d'utilisation des terres. Les implications de tels changements pour A. uranoscopus sont discutées. [source] Room-Temperature Conducting LaNiO3 Thick-Film Coatings Prepared by Aerosol DepositionJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 8 2008Jong-Jin Choi Metallic conductive LaNiO3 thick films with a thickness of 0.5,10 ,m were fabricated by a room-temperature-operating powder deposition process,aerosol deposition method. The coated LaNiO3 layers were fairly dense without pores or cracks, and maintained their phase stability due to low-temperature consolidation. The as-deposited LaNiO3 film consisted of ,10-nm-diameter grains, with a sheet resistance of 10,100 ,/,, while the post-annealed LaNiO3 film had a sheet resistance of 4.45 ,/,, which is the lowest value ever reported for an LaNiO3 film. This excellent conductivity result was attributed to the high crystal stability and dense microstructure. [source] Effect of fat replacers on kefir qualityJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 4 2010Bilge Ertekin Abstract The purpose of the study was to determine the effects of fat replacers on the quality of non-fat kefir. Skim milk fortified with Dairy Lo® (DL) and inulin (INU) was fermented with kefir grains to manufacture kefir. The results of compositional, microbiological, rheological and sensorial analyses were compared with whole kefir (WK) and non-fat kefir (NFK) controls. Results for dry matter, pH and lactic acid ranged between 82.4 and 109.1 g kg,1, 4.26 and 4.40, and 7.0 and 9.2 g L,1, respectively. Acetaldehyde and ethanol contents of samples were between 2.89 and 7.28 mg L,1, and 151.46 and 323.89 mg L,1, respectively. In all samples, Lactobacillus spp., Streptococcus spp. and yeast counts were between 9.1 and 9.9, 9.3 and 9.9, and 5.2 and 5.6 log cfu mL,1, respectively. Kefir samples had non-Newtonian behaviour and pseudoplastic fluid with thixotropy. At the first day, DL had the highest apparent viscosity (3.119 Pa s) while NFK had the lowest value (1.830 Pa s). In the sensory evaluation, odour and taste scores of samples were not different. Dairy Lo® and inulin could be used without any adverse effect for the production of non-fat kefir. Copyright © 2009 Society of Chemical Industry [source] Adhesion of Er:YAG laser-irradiated dentin and composite resins: Application of various treatments on irradiated surfaceLASERS IN SURGERY AND MEDICINE, Issue 4 2002Toru Eguro DDS Abstract Background and Objectives The investigation of adhesion between an Er:YAG laser-irradiated surface and composite resin is very important to ensure the best clinical results. The purpose of this investigation is to determine if the application of various treatments on Er:YAG laser-irradiated dentin surface affects the tensile bond strength between dentin and composite resins. Study Design/Materials and Methods In this investigation, the application of phosphoric acid, ultrasonic scaler, air-scaler, and air-powder polisher were tested as techniques to increase the bond strength of composite resins to Er:YAG laser-irradiated dentin surface. Results The tensile bond strength of the air-powder polished group was highest, at 18.45,±,3.72 MPa, and the lowest value was that of the only laser-irradiated group, at 12.56,±,4.38 MPa. Conclusions The bond strengths in treated with air-powder polished group and phosphric acid etched group were significantly higher than that of the group in laser irradiation alone. Lasers Surg. Med. 30:267,272, 2002. © 2002 Wiley-Liss, Inc. [source] Influence of imidazolium-based ionic liquids on the performance of ionic polymer conductor network composite actuatorsPOLYMER INTERNATIONAL, Issue 3 2010Sheng Liu Abstract We investigated the influence of ionic liquids (ILs) on the electromechanical performance of ionic polymer conductor network composite (IPCNC) actuators. Four imidazolium ILs with two cations of different sizes, i.e. 1-ethyl-3-methylimidazolium ([EMI+]) and 1-butyl-3-methylimidazolium ([BMI+]), and two anions of different sizes, i.e. tetrafluoroborate ([BF4,]) and trifluoromethanesulfonate ([Tf,]), were used. The IPCNC actuators were fabricated using a direct assembly method with RuO2/Nafion® nanocomposite as the electrode layers. The experimental results reveal that the actuator strain response time is nearly one order of magnitude shorter than the charging time. The IPCNCs with [EMI+][Tf,] exhibit the highest capacitance and the fastest response in both actuation and electrical charging as capacitors. In contrast, the IPCNCs with [EMI+][BF4,] display the slowest charging time and lowest value of capacitance as capacitors. The IPCNCs with [BMI+][BF4,] show the slowest response time. Furthermore, although the ILs used have a marked effect on the capacitances of the IPCNCs, using different ILs does not cause much change in the maximum strain of these IPCNCs. Consequently, the IPCNC actuators with [EMI+][BF4,] show the highest electromechanical conversion efficiency while those with [EMI+][Tf,] have the lowest electromechanical efficiency because of the highest capacitance and largest input electrical energy. The experimental results indicate that the two oppositely charged ions contribute in opposite manner to the strain response and hence the observed shorter actuation response time is likely caused by the strain cancellation effect between the cations and anions. Copyright © 2010 Society of Chemical Industry [source] Neuronal loss and neurofibrillary degeneration in the hippocampal cortex in late-onset sporadic Alzheimer's diseasePSYCHIATRY AND CLINICAL NEUROSCIENCES, Issue 5 2000Yuken Fukutani MD Abstract To explore more fully the relationship between neuronal death and neurofibrillary degeneration, unaffected neurons, intracellular neurofibrillary tangles (i-NFT) and extracellular NFT (e-NFT) in 22 patients with late-onset sporadic Alzheimer's disease (AD) were morphometrically evaluated in eight subdivisions of the hippocampal cortex, using the Gallyas hematoxylin-eosin stain. The subdivisions examined included CA4, CA3, CA2, CA1 (CA: cornu ammonis), prosubiculum (PRO), subiculum and presubiculum (PRE), parasubiculum (PARA) and the entorhinal cortex (ENT). The unaffected neuron density was significantly lower and both i-NFT and e-NFT densities were significantly higher in subdivisions other than CA4 and CA3 in AD patients compared with those in the aged controls. Unaffected neuron density was significantly, inversely correlated with e-NFT density and with total NFT density in all subdivisions except for PRE in AD patients. Especially in CA2, CA1, PRO and ENT, there were strong correlations between the neuron density and these NFT densities. Both unaffected neuron and e-NFT densities in CA1 and ENT were significantly correlated with the disease duration. The i/e-NFT ratio, an index of the degree and/or rate of progress of neuronal death via neurofibrillary degeneration, showed the lowest value in ENT in AD patients. The findings suggest that neuronal death via neurofibrillary degeneration starts earliest and/or most rapidly progresses in ENT. Furthermore, the i/e-NFT ratios in both ENT and CA1 were significantly correlated with the disease duration, suggesting that the neuronal death pattern in the two subdivisions parallels disease progression. [source] Relationships between milk characteristics and somatic cell score in milk from primiparous browsing goatsANIMAL SCIENCE JOURNAL, Issue 5 2010Giuseppe M. VACCA ABSTRACT To determine milk yield and composition, total microbic count (TMC) and somatic cell count (SCC) of browsing goats throughout the first lactation, 100 goats of Sarda breed, equally distributed in four flocks (F1, F2, F3 and F4), were selected. They were exclusively fed pasture and hand-milked once daily. Individual milk samples and daily milk yield were taken from each goat at monthly intervals, from March to July. Milk samples were analyzed for: total protein, fat, lactose, urea, freezing point (FP), pH, TMC and SCC. The data was subjected to analysis of variance and to correlation matrix. On the whole, in all the flocks, milk yield showed the highest production in April and May. Fat content increased (P < 0.01) throughout the lactation. Protein content showed the lowest value (P < 0.01) in June (4.15%). Urea and pH values were fluctuating. FP was lower (P < 0.01) at the start of lactation (,0.562 Hortvet degrees). TMC log10 values were low, considering the hand milking and inadequacy of facilities on the farms. SCC increased (P < 0.01) throughout the lactation and, on the whole, SCC and TMC were not correlated. [source] Effect of different levels of Quebracho tannin on nitrogen utilization and growth performance of Najdi sheep fed alfalfa (Medicago sativa) hay as a sole dietANIMAL SCIENCE JOURNAL, Issue 5 2009Soliman N. AL-DOBAIB ABSTRACT A commercial tannin source (Quebracho tannin, QT), containing 75% condensed tannins (CT) in dry matter (DM) was used to evaluate the effects of addition of different levels of QT to alfalfa hay on the in vitro degradation kinetics of organic matter (OM) and nitrogen (N) in experiment 1 (Exp. 1), N utilization and microbial N synthesis (MNS) in experiment 2 (Exp. 2) and growth performance of growing Najdi lambs in experiment 3 (Exp. 3). Alfalfa hay was treated with QT at the levels of 0, 1, 2 and 3% of DM to form four treatments of QT0, QT1, QT2 and QT3 to have actual levels of CT being 0, 0.75, 1.5 and 2.25% of DM, respectively. Degradation rate and the effective degradability of N were significantly decreased (P < 0.05) for QT2 and QT3 as compared with the QT0. In Exp. 2, digestibility coefficients for OM, neutral detergent fiber and acid detergent fiber were significantly decreased (P < 0.05) at QT3, whereas QT1 and QT2 showed no difference toQT0. In the metabolism trial (Exp. 2), digested N (DN) and urinary N (UN) excretion for QT2 and QT3 were significantly decreased (P < 0.05) compared to QT0 and QT1. The DN and UN as percentage of N intake were 79.2, 76.9, 75.5 and 69.8%; and 24.4, 22.6, 19.9 and 19.6% for QT0, QT1, QT2 and QT3, respectively. QT2 had the highest MNS and the lowest value was in QT3, the MNS of the treatments were 18.1, 18.7, 19.2 and 15.8 g/day for QT0, QT1, QT2 and QT3, respectively. In the growth trial of 56 days duration (Exp. 3, n = 24 lambs), the addition of QT at the level of QT2 enhanced (P < 0.05) the average daily gain and feed conversion rate compared with the QT0, while, QT1 and QT3 had intermediate values. It is concluded that alfalfa hay treated with QT at the level of 2% of DM could be used to protect alfalfa N from ruminal degradation that would lead to improve growth performance of lambs. [source] Investigation of fat content in market common carp (Cyprinus carpio) flesh during the growing seasonAQUACULTURE NUTRITION, Issue 5 2010M. URBÁNEK Abstract Effects of supplemental feeding with cereals (rye, triticale, maize and the unsupplemental control group) on fat content in flesh of 3-year-old common carp (Cyprinus carpio) were the subject of study carried out at four ponds (Czech Republic, Central Europe) during the growing season. The main result was that supplemental feeding with cereals to the same energetic level was associated with varying growth and fat content in the flesh of common carp. At the end of the experiment, the stock of fish supplementally fed with maize was found to have the highest fat content (112.7 ± 15.6 g kg,1), while the lowest value of fat content was found in the control group (56.8 ± 9.4 g kg,1). The carps supplementally fed with rye were found to have a higher fat content (90.1 ± 19.0) than those supplementally fed with triticale (84.3 ± 15.7 g kg,1). Established average fat content values (except for maize) were at the level that indicate a high sensory quality of carp flesh during the whole growing season. [source] Starch source, screw configuration and injection of steam into the barrel affect the physical quality of extruded fish feedAQUACULTURE RESEARCH, Issue 3 2010Mette Sørensen Abstract This experiment investigated the physical qualities (,Holmen' durability; ,tumbling box' durability; and pellet strength, length and diameter) of extruded fishmeal-based feeds produced using different starch sources, screw configurations, with or without steam injected in the barrel. The starch sources tested were native or pre-gelatinized potato starch (PGS), wheat starch (WS), whole wheat (WW) or a combination of WS and WW. Screw configurations were a polygon element, followed by two left-pitched segments, Polygon_2L; a polygon, followed by one left-pitched and one right-pitched element, Polygon_LR; and no polygon section, alternating left- and right-pitched elements, LRLR. Starch source and screw configuration affected the physical quality the most. Pellets produced with LRLR had the highest ,Holmen' durability (76%), hardness (30 N) and the least diameter (5.3 mm). The lowest durability (37%) and hardness (22 N) were obtained with Polygon_LR. Potato starch yielded higher expansion than cereal starch. The highest ,Holmen' durability was seen for PGS (79%), while WS yielded the lowest value (44%). Injection of steam reduced hardness and ,Holmen' durability, but provided a minor overall contribution to physical quality compared with the starch source and screw configuration. ,Holmen' durability appeared to be suitable to unveil variation (37,79%) in physical quality, while ,Tumbling box' durability (98.4,98.8%) did not prove efficient. [source] Live Spirulina (Arthrospira platensis) as a growth and immunity promoter for Nile tilapia, Oreochromis niloticus (L.), challenged with pathogenic Aeromonas hydrophilaAQUACULTURE RESEARCH, Issue 9 2009Mohsen Abdel-Tawwab Abstract The use of antibiotics to control fish disease is one of the constraints in tilapia farming. Hence, the use of probiotic and live organisms as alternative strategies has received much more attention. This study was undertaken to evaluate the use of Spirulina (Arthrospir platensis) as a growth and immunity promoter for Nile tilapia, Oreochromis niloticus (L.). Fish (1.88 g) were randomly distributed at 20 fish per 100 L aquarium and fed a diet containing either 0.0, 1.25, 2.5, 5.0, 7.5 or 10.0 g Spirulina kg,1 diet for 12 weeks. After the feeding trial, fish of each treatment were challenged by pathogenic Aeromonas hydrophila, which was given by an interperitoneal injection, and they were kept under observation for 10 days to record any abnormal clinical signs and the daily mortality rate. The growth-promoting influence of Spirulina was observed with fish, and the optimum growth and feed utilization were obtained at 5.0 g Spirulina kg,1 diet. No significant changes were observed in fish survival among the different treatments. Spirulina supplementation improved the protein and lipid contents in fish bodies without significant differences among them, especially when fed 2.5,10.0 g kg,1 diet, but no significant differences in the moisture and ash contents were observed among different treatments. The physiological parameters were improved when fish were fed a Spirulina-enriched diet. However, the highest red blood cells, white blood cells and nitro blue tetrazolium values were obtained at 5.0,10.0 g Spirulina kg,1 diet; meanwhile, the lowest value was obtained in the control. Total fish mortality due to A. hydrophila infection decreased with an increase in the Spirulina level in fish diets. These results indicate that Spirulina supplement is promising as an alternative method to antibiotics for disease prevention in tilapia aquaculture, and the optimum level of Spirulina in the fish diet should be 5.0,10.0 g kg,1 diet. [source] Variation in multiple paternity and sperm utilization patterns in natural populations of a simultaneous hermaphrodite land snailBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 2 2010SANDRA KUPFERNAGEL Mating frequency has important implications for patterns of sexual selection and sexual conflict, and hence for issues such as the maintenance of genetic diversity and speciation. We assessed the level of multiple paternity and sperm utilization patterns in four natural populations of the simultaneous hermaphrodite land snail Arianta arbustorum using four polymorphic microsatellite loci. A total of 1088 offspring from 26 wild-caught snails were genotyped to determine the number of fathers siring each brood and paternity skew in succeeding clutches. Multiple paternity was detected in the offspring of all 26 mother snails examined with the contribution of two to six fathers. The four populations examined differed in the level of multiple paternity. Snails in the population with the highest density of adults showed the highest level of multiple paternity, whereas snails in the population with the lowest density exhibited the lowest value of multiple paternity. Highly skewed paternity patterns were found in the progeny of 15 (57.7%) of the 26 mother snails. The number and identity of fathers siring the offspring of single mothers also varied among successive clutches. Furthermore, genetic analyses indicate a low level of self-fertilization in one of the four populations. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 99, 350,361. [source] Disila-Okoumal: A Silicon Analogue of the Ambergris Odorant OkoumalCHEMBIOCHEM, Issue 12 2007Matthias W. Büttner Abstract Two-fold sila-substitution (C/Si exchange) in the saturated ring of the tetrahydronaphthalene skeleton of the ambery odorant okoumal (5) provides disila-okoumal (6). The okoumal isomers 5,a,d were synthesized from 1-(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-2-naphthyl)ethanone (7), and the silicon analogues 6,a,d were synthesized from 1-(5,5,8,8-tetramethyl-5,8-disila-5,6,7,8-tetrahydro-2-naphthyl)ethanone (8). Detailed olfactory properties of 5,a,d and 6,a,d are reported, together with the respective threshold values. All enantiomers of okoumal and disila-okoumal exhibit typical ambery odor notes with woody facets, as is characteristic of okoumal and karanal, but a stereocenter at the 2-position was found to be of utmost importance for the odor thresholds; the lowest value of 0.31 ng per L air was measured for the 2R -configured silicon compounds 6,a and 6,c. [source] Gross rates of ammonification and nitrification at a nitrogen-saturated spruce (Picea abies (L.)Karst.) stand in southern GermanyEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 5 2010P. Rosenkranz We investigated the magnitudes of temporal and spatial variabilities of gross ammonification and nitrification, in an N-saturated temperate forest ecosystem. Forest soil gross ammonification, gross nitrification and heterotrophic soil respiration were measured in the forest floor and uppermost mineral layer over a period of 3 years. Total annual gross fluxes for the organic layer and uppermost mineral horizon (0,4 cm) were in the range of 800,980 kg N ha,1 year,1 for gross ammonification and 480,590 kg N ha,1 year,1 for gross nitrification. Annual heterotrophic soil respiration was 8000,8900 kg C ha,1 year,1. Highest soil C and N turnover rates occurred in summer, and a consistent pattern was observed throughout the observation period, with highest values for plots located at a clear-cut area and lowest values for plots located at an unmanaged, approximately 100-year-old, spruce control site. Soil moisture, soil temperature and substrate availability accounted for most of the observed variability of C and N turnover rates. Because gross rates of inorganic N production were more than an order of magnitude larger than ecosystem N losses along hydrological and gaseous pathways, our study underlines the importance of internal microbial N turnover processes for ecosystem N cycling and retention. [source] SEASONAL CYCLES OF ALLOZYME-BY-CHROMOSOMAL-INVERSION GAMETIC DISEQUILIBRIUM IN DROSOPHILA SUBOBSCURAEVOLUTION, Issue 4 2003Francisco Rodríguez-Trelles Abstract Allozyme loci are frequently found non randomly associated to the chromosomal inversions in which they are included in Drosophila. Two opposite views compete to explain strong allozyme-by-inversion gametic disequilibria: they result from natural selection or, conversely, merely represent remnants of associations accidentally established at the origin of inversions. Empirical efforts aimed at deciding between adaptive and historical scenarios have focused on the spatial distribution of disequilibria. Yet, the evolutionary significance of these associations remains uncertain. I report here the results of a time-series analysis of the seasonal variation of alleles at six allozyme loci (Acph, Lap, Pept-1, Ao, Mpi, and Xdh) in connection with the O chromosomal polymorphisms of D. subobscura. The findings were: (1) in the segment I of the O chromosome, Lap and Pept-1 allozymes changed seasonally in a cyclical fashion within the ST gene arrangement, but they changed erratically within the 3+4 gene configuration; (2) the frequencies of Lap111 and Pept-10,40 within ST dropped to their lowest values in early and late summer, respectively, when the seasonal level of the ST arrangement is lowest. Furthermore, Lap1,11 and Pept-10,40 covary with ST only within these seasons, yet in a fashion inconsistent with these alleles having a major influence on the dynamics of the inversion; (3) seasonal cycling of alleles within inversions were not detected at Acph, Ao, Mpi, and Xdh, yet these loci are nearly monomorphic at the study population, and/or their sampled series were shorter than those for Lap and Pept-1; and (4) simply monitoring allozyme frequencies separately for each inversion proved to be superior, for evidencing the seasonal cycles of the disequilibria, to the use of the D' coefficient of association. Observed seasonal cycles of allozymes within inversions likely reflect natural selection. [source] Interannual and seasonal variability of the diversity and structure of ichthyoplankton assemblages in the central Mexican PacificFISHERIES OCEANOGRAPHY, Issue 3 2008C. FRANCO-GORDO Abstract We examined larval fish diversity and assemblage structure off the central coast of the Mexican Pacific from December 1995 through December 1998, including the 1997,98 El Niño event. A total of 132 taxa were recorded, the dominant species being Bregmaceros bathymaster, Dormitator latifrons, and Harengula thrissina (90, 1.9, and 0.8% of the total abundance, respectively). Only B. bathymaster, D. latifrons, and Gobionellus sp. occurred in all samples. The effects of the 1997,98 El Niño on ichthyoplankton diversity were significant, but typical seasonal patterns were also detected. Diversity null models were used to determine the structural changes in the assemblage related to El Niño; both richness and evenness of the species were highest during this event. The most parsimonious models of assemblage organization include El Niño and seasonality as the most significant environmental variability sources. The small-scale spatial variability expressed as the cross-shore gradient was not significant. The dominant species group formed by B. bathymaster, D. latifrons, and Vinciguerria lucetia typifies, in terms of similarity, both the pre-El Niño and El Niño periods; abundance differed between periods. The El Niño period was characterized locally by the dominant Bentosema panamense and H. thrissina, by the rare Euthynnus lineatus, and species of Lutjanus. Seasonality produced changes also in the relative frequencies of the dominant species plus the occurrence of rare forms. The average taxonomical distinctness, considered herein as an indicator of functional diversity, reflected the seasonal variability of the assemblages, aside from El Niño; this index showed lowest values during tropical and transitional periods, both characterized by warm, oligotrophic waters. The high dominance of B. bathymaster in the area and its effect on diversity stabilized the local ichthyoplankton assemblage. An upgraded analysis of diversity allowed a more detailed description of the variability in this assemblage, thus stressing the differential effects of El Niño at distinct latitudes. [source] A thermodynamic analysis of the anaerobic oxidation of methane in marine sedimentsGEOBIOLOGY, Issue 5 2008D. E. LAROWE ABSTRACT Anaerobic oxidation of methane (AOM) in anoxic marine sediments is a significant process in the global methane cycle, yet little is known about the role of bulk composition, temperature and pressure on the overall energetics of this process. To better understand the biogeochemistry of AOM, we have calculated and compared the energetics of a number of candidate reactions that microorganisms catalyse during the anaerobic oxidation of methane in (i) a coastal lagoon (Cape Lookout Bight, USA), (ii) the deep Black Sea, and (iii) a deep-sea hydrothermal system (Guaymas basin, Gulf of California). Depending on the metabolic pathway and the environment considered, the amount of energy available to the microorganisms varies from 0 to 184 kJ mol,1. At each site, the reactions in which methane is either oxidized to , acetate or formate are generally only favoured under a narrow range of pressure, temperature and solution composition , particularly under low (10,10 m) hydrogen concentrations. In contrast, the reactions involving sulfate reduction with H2, formate and acetate as electron donors are nearly always thermodynamically favoured. Furthermore, the energetics of ATP synthesis was quantified per mole of methane oxidized. Depending on depth, between 0.4 and 0.6 mol of ATP (mol CH4),1 was produced in the Black Sea sediments. The largest potential productivity of 0.7 mol of ATP (mol CH4),1 was calculated for Guaymas Basin, while the lowest values were predicted at Cape Lookout Bight. The approach used in this study leads to a better understanding of the environmental controls on the energetics of AOM. [source] Nitrogen balance and seasonal fluctuations in soil nitrogen contents in a corn (Zea mays L)-rye (Secale cereale L) rotation fieldGRASSLAND SCIENCE, Issue 1 2005Yuzo Kurokawa Abstract In a corn (Zea mays L)-rye (Secale cereale L) rotation field, the N output (plant uptake) and N input (crop residue and fertilizer applied) were measured for two years in order to evaluate the N balance in a forage production field. The soil was Low-humic Andosol (mesic Typic Hapludand). The disappearance of crop residues on both a dry matter and N basis, and the seasonal fluctuations of total, inorganic, and available soil N content in the field were investigated. The interaction between the nitrogen balance and the soil N contents are discussed. The total plant N uptake of the corn and rye exceeded the sum of the N input of the fertilizer applied and the N from crop residues, so the N balance of the corn-rye rotation had a negative value (two year average: ,8.4 gN m,2). After the gradual disappearance of crop residue on the dry matter basis, rapid disappearance on the N basis was observed. At the same time, the C/N ratio decreased to less than 20. The soil available (38.4,55.3 mg kg,1) and inorganic (21.5,45.2 mg kg,1) N had their lowest values in spring. After they increased in early summer, they decreased in late summer and increased in autumn. The total N (0.5,0.7%) gradually decreased during the experimental period. The results indicated that the soil-available N and inorganic N in the present study were highly dependent on the fertilizer-applied N. The relation among management practices, N input and soil available N contents are discussed. It is suggested that the negative N balance is one of the causes for a decrease in soil total N. [source] The Ratios of Carbon, Nitrogen, and Phosphorus in a Wetland Coastal Ecosystem of Southern IndiaINTERNATIONAL REVIEW OF HYDROBIOLOGY, Issue 2 2003Lizen Mathews Abstract The fertility of the coastal and estuarine waters is of great concern because of its influence on the productivity of these waters. Seasonal variations in the distribution of organic carbon, total nitrogen and total phosphorus in the sediments of Kuttanad Waters, a part of the tropical Cochin Estuary on the south west coast of India, are examined to identify the contribution of sediments to the fertility of the aquatic systems. The adjoining region has considerable agricultural activity. The fresh water zones had higher quantities of silt and clay whereas the estuarine zone was more sandy. Organic carbon, total phosphorus and total nitrogen were higher in the fresh water zones and lower in the estuarine zones. Total phosphorus and organic carbon showed the lowest values during monsoon periods. No significant trends were observed in the seasonal distributions of total nitrogen. Ratios of C/N, C/P and N/P, and the phosphorus and nitrogen content indicate significant modification in the character of the organic matter. Substantial amounts of the organic matter can contribute to reducing conditions and modify diagenetic processes. [source] Fermentation characteristics and microbial growth promoted by diets including two-phase olive cake in continuous fermentersJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 1 2008A. Moumen Summary Two-phase olive cake (2POC) is the by-product obtained from the so called ,two-phase' procedure to extract olive oil by mechanical methods. After the mechanical extraction the 2POC is dried and most of the remaining oil extracted by chemical means. The production of the crude by-product may reach more than 4 millions t/year in Spain (MAPA, 2003), most of it in areas (Southeast) with shortage of pastures and conventional feeds for ruminants. Six continuous fermenters, inoculated with ruminal liquor from wethers or goats, were fed lucerne hay (LH); LH plus a concentrate including dried two-phase olive cake (LHCO) and; diet LHCO added with polyethylene glycol (LHCOP). The highest pH values and ammonia N (NH3 -N) output were found in fermenters fed diet LH (6.19 and 6.35 for pH, and 53.7 and 68.9 mg NH3N/day, respectively, in fermentes inoculated with rumen liquor from sheep and goats) without differences due to the inoculum origin. The digestibility of carbohydrates (CHO) was affected (p < 0.001) by inoculum (67.0 and 58.8%, respectively, for goats and wethers) the lowest values being for diet LHCO (53.2 and 57.0% with inoculum from wethers and goats, respectively). The main volatile fatty acid (VFA) was acetic acid with higher (p < 0.01) values in fermenters with inoculum from goats than from wethers (80.2 and 63.0 mmol/day respectively). The efficiency of bacterial protein synthesis (EBS) was not different (p > 0.05) with inoculum from wethers and goats [26.4 and 28.1 and 35.2 and 33.5 g bacterial N/kg digested CHO, respectively, obtained by using diamino pimelic acid (DAPA) and purine bases (PB) as microbial markers]. The lowest (p < 0.05) values were found in fermenters fed diets LHCOP and LH, estimated, respectively, from DAPA and PB (21.9 and 29.0 g bacterial N/kg digested CHO). The substitution of a part of lucerne hay by a concentrate including dried 2POC does not seem to cause important differences in efficiency of VFA production. Results concerning bacterial protein synthesis are not so clear since values estimated from DAPA and PB did not show similar trends. Neither inoculum origin nor PEG had important effects on fermentation characteristics. The DAPA could be an adequate marker in continuous fermenters, with comparative purposes, as protozoa are not present and, estimated protein synthesis values are similar to those obtained in vivo with similar diets using urinary excretion of PD (Yáñez Ruiz et al., 2004b). Further research is needed to state the optimal proportion of 2POC in practical diets for ruminants at both maintenance and production stages. [source] Diurnal rhythm in heat production and oxidation of carbohydrate and fat in pigs during feeding, starvation and re-feedingJOURNAL OF ANIMAL PHYSIOLOGY AND NUTRITION, Issue 7-8 2004A. Chwalibog Summary Diurnal rhythm in heat production (HE), oxidation of carbohydrate (OXCHO) and fat (OXF) was calculated from daily measurements of gas exchange in 12 pigs [20,40 kg live weight, (LW)] during 6 days of near ad libitum feeding, followed by 4 days of starvation and 4 days of re-feeding. All measurements, divided in five times intervals from 12.00 to 8.00, showed the highest values of HE, reflecting the animals' energy requirements, between 12.00 and 16.00 gradually declining to the lowest values between 4.00 and 8.00. The values measured in the interval 4.00,8.00 were considered as a basal metabolic rate (BMR), being in all measurements 25% lower than during 12.00,4.00. The lowest BMR was measured on the fourth day of starvation (21.7 kJ/h·kg0.75). By transition from feeding to starvation, OXCHO declined gradually, but was for 16 h able to cover the energy requirement with no contribution from OXF. The decline in OXCHO proceeded for 40 h and reached zero between 4.00 and 8.00 on the first day of starvation with the energy requirement being covered by OXF. The HE during starvation was 25,30% lower than during feeding caused by absence of feed-induced thermogenesis and by the transition from OXCHO to OXF. Immediately after re-feeding dietary carbohydrates were oxidized, however, there was still a substantial OXF, proceeding until the next feeding. From the second day of re-feeding the contribution of substrates to the total HE was re-established with no OXF and the same level of HE as during feeding. [source] | |||||||||||||||||||||||||