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Phosphorus Content (phosphorus + content)
Selected AbstractsPROPERTIES of CROSS-LINKED STARCH PRODUCED IN A SINGLE SCREW EXTRUDER WITH and WITHOUT A MIXING ELEMENTJOURNAL OF FOOD PROCESS ENGINEERING, Issue 1 2004M. SEKER ABSTRACT Starch was extruded with sodium hydroxide and sodium trimetaphosphate in order to cross-link it in a single-screw extruder with and without a mixing element at constant screw speed of 90 rpm in the first set of experiments and at similar mean residence time controlled by screw speed in the second set of experiments. For the screw without mixing element in the second set of experiments, screw speed was adjusted to give the similar residence time as the single-screw extruder with mixing element at 220 rpm. Phosphorus content and pasting curves of extrudates showed that starch was cross-linked during extrusion. Replacing the screw without mixing element by the screw with mixing [source] Phosphorus requirements of gilthead sea bream (Sparus aurata L.) juvenilesAQUACULTURE RESEARCH, Issue 2001A M Pimentel-Rodrigues Abstract A trial was conducted to evaluate the phosphorus requirements of gilthead sea bream juveniles. Seven semipurified diets were formulated to contain 54% crude protein and 15% lipids and phosphorus (di-calcium phosphate) levels ranging from 0.37% to 1.5% (DM basis). Each diet was fed to duplicate groups of 25 fish with an initial average weight of 5 g over 42 days. The fish were fed by hand to visual apparent satiety twice daily, six days a week. At the end of the trial growth rate was not significantly different in groups fed diets containing 0.75% phosphorus or higher, while growth rate of fish fed the 0.37% phosphorus diet was significantly lower than all the other diets. Feed efficiency ratio, protein efficiency ratio and N retention were significantly lower in fish fed the 0.37% phosphorus diet than in those fed diets with 0.75% and higher phosphorus levels. Phosphorus content of the fish averaged 2% (on a dry weight basis) and was not significantly affected by dietary phosphorus content. Phosphorus retention averaged 6.6 g kg,1 weight gain and was not statistically different among groups. Phosphorus retention (% phosphorus intake) decreased with the increase of dietary phosphorus content, being even higher than 100% in groups fed diets with 0.37% and 0.57% phosphorus, indicating phosphorus absorption from the water. The results of this study indicate that phosphorus requirements of gilthead sea bream juveniles were satisfied with a diet including 0.75% phosphorus. [source] Predator-released compounds, ambient temperature and competitive exclusion among differently sized Daphnia speciesFRESHWATER BIOLOGY, Issue 4 2006JACOBUS VIJVERBERG Summary 1. We studied the effects of fish water and temperature on mechanisms of competitive exclusion among two Daphnia species in flow-through microcosms. The large-bodied D. pulicaria outcompeted the medium sized D. galeata × hyalina in fish water, but not in the control treatment. Daphnia galeata × hyalina was competitively displaced 36 days earlier at 18 °C than at 12 °C. 2. It is likely that the high phosphorus content of fish water increased the nutritional value of detrital seston particles by stimulating bacterial growth. Daphnia pulicaria was presumably better able to use these as food and hence showed a more rapid somatic growth than its competitor. This led to very high density of D. pulicaria in fish water, but not in the controls. The elevated D. pulicaria density coincided with high mortality and reduced fecundity in D. galeata × hyalina, resulting in competitive displacement of the hybrid. 3. It is clear that the daphnids competed for a limiting resource, as grazing caused a strong decrease in their seston food concentration. However, interference may also have played a role, as earlier studies have shown larger Daphnia species to be dominant in this respect. The high density of large-bodied D. pulicaria in fish water may have had an allelopathic effect on the hybrid. Our data are inconclusive with respect to whether the reached seston concentration was below the threshold resource level (R*) of the hybrid, where population growth rate and mortality exactly balance, as it would be set in the absence of interference, or whether interference actually raised the hybrid's R* to a value above this equilibrium particle concentration. 4. Our results do clearly show that fish-released compounds mediated competitive exclusion among zooplankton species and that such displacement occurred at a greatly enhanced rate at an elevated temperature. Fish may thus not only structure zooplankton communities directly through size-selective predation, but also indirectly through the compounds they release. [source] Biochemical changes during the ripening of homemade ,San Simón da Costa' raw milk cheeseINTERNATIONAL JOURNAL OF DAIRY TECHNOLOGY, Issue 1 2008E L NHUCH ,San Simón da Costa' cheese is a traditional smoked variety produced in the northwest of Spain from cow's milk. Biochemical changes were determined during its ripening. Its high calcium and phosphorus content and its low NaCl and sodium content stand out. This cheese undergoes moderate proteolysis. The most abundant free amino acid at the end of the ripening was glutamic acid, followed by tryptophan, leucine, arginine and phenylalanine. The lipolysis throughout ripening is slight; the most abundant free fatty acid being oleic, followed by palmitic and butyric acid. [source] Influence of a Trout Farm on Water Quality and Macrozoobenthos Communities of the Receiving Stream (Tre,njica River, Serbia)INTERNATIONAL REVIEW OF HYDROBIOLOGY, Issue 6 2009Ivana Abstract Trout farming is constantly increasing and poses a serious threat to water quality of clean highland streams. In the present work, we investigated the influence of the farm with the highest trout production in Serbia on water quality and macrozoobenthos communities of the receiving stream, the Tre,njica River. Our study revealed that changes of water chemistry parameters downstream from the trout farm were moderate and mainly confined to the part of the watercourse closest to the wastewater outlet. Moreover, use of food with 0.8% phosphorus content was sufficient to completely eliminate soluble phosphates from water samples of the Tre,njica River. However, the changes in water chemistry were sufficient to cause significant changes in the macrozoobenthos community. These changes remained statistically significant even 500 m downstream and were lost about 3.5 km from the trout farm wastewater effluent. The trout biomass on the farm is a parameter that adequately defines the magnitude of its impact, above all the intensity of its influence on the zoobenthos community structure. The most informative parameters for estimating that influence were the Baetidae/Ephemeroptera ratio, Margelef's index and the Modified biotic index. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] The geographical range structure of the holly leaf-miner.JOURNAL OF ANIMAL ECOLOGY, Issue 5 2004Summary 1Spatial variation and covariation in host-plant quality, herbivore abundance and herbivore mortality were examined across the natural geographical range in Europe of holly Ilex aquifolium and the host-specific holly leaf-miner Phytomyza ilicis. 2Although measures of host-plant quality showed substantial between-site variation, no simple spatial pattern in any of the measures (only phosphorus content and leaf mass showed correlations with latitude, longitude or altitude) was detected, and few correlations with tree or local site characteristics. 3In contrast, measures of the abundance of the leaf-miner exhibited marked spatial patterns, resulting in a lack of simple covariance between leaf-miner abundance and host-plant quality. 4Different apparent mortalities of the leaf-miner exhibited varied spatial patterns in their intensity, but no evidence of range-wide density dependence, again resulting in few patterns of covariance between intensity of mortality and measures of host-plant quality. 5The population dynamics of the holly leaf-miner across its geographical range are complex. At any site, the mortality that a population experiences is the sum of largely independent yet spatially structured components, against a background of varying host-plant quality. Despite lacking any marked spatial structure, host-plant quality may have important local effects. These are difficult to detect regionally, and thus may principally contribute noise to regional patterns of levels of oviposition, abundance and mortality. [source] Long-term enhancement of agricultural production by restoration of biodiversityJOURNAL OF APPLIED ECOLOGY, Issue 1 2007JAMES M. BULLOCK Summary 1Experimental manipulations have shown positive impacts of increased species richness on ecosystem productivity, but there remain some questions about this relationship. First, most studies last < 4 years, which raises issues about whether diversity,productivity relationships are maintained in mature communities. Secondly, the conservation relevance of many studies is debatable. We addressed both issues using long-term experimental studies of the agriculturally relevant hay yield of recreated species-rich grasslands. 2Grasslands were recreated within replicated experiments in ex-arable fields at two sites in southern England by using either species-poor or species-rich seed mixtures. The species-poor mixture comprised seven grasses as recommended for grassland creation in English agri-environment schemes. The species-rich mixture comprised 11 grasses and 28 forbs and was designed to recreate a typical southern English hay meadow. 3After 8 years the plots sown with species-rich mixtures resembled target diverse community types. The plots sown with species-poor mixtures had been colonized by a number of forbs but had lower numbers of grasses, legumes and other forbs than the species-rich plots. Increased hay yield of the species-rich plots in the first years of the experiments have been described in an earlier paper, and these differences were maintained after 8 years. 4In the eighth year the species-rich plots had an average 43% higher hay yield than the species-poor plots. Regression analysis showed that the variation in hay yield was related to differences in the number of non-leguminous forbs and showed no relation to grass or legume numbers. This suggests increased hay yield is an effect of the greater range of life forms exhibited by forbs rather than a simple fertilizing effect of legumes. 5The nitrogen content and phosphorus content of the hay showed complex treatment effects over time. However, the nutritional value of the hay was above the minimum requirements for livestock. 6Synthesis and applications. The aims of conservationists and farmers can often be in conflict. This study has shown that the recreation of diverse grasslands of conservation value can have a positive impact on hay yield, which benefits the farm business, and this is repeated across differing sites. Because the effect is maintained over time, farm income will be increased in the long term. [source] Olive oil mill wastewater valorisation by fungiJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 9 2006Silvia Crognale Abstract This paper presents a brief survey of studies conducted at the Laboratory of Applied and Environmental Microbiology of the University of Tuscia on the possible biotechnological valorisation of olive mill wastewater (OMW) using fungi. Besides being a serious environmental problem, OMW might be a possible resource owing to the presence of added value products (e.g. antioxidants) and of simple and complex sugars as a basis for fermentation processes. To this end the technical feasibility of various fungal fermentative processes either to obtain products of high added value or to improve its agronomic use has been assessed. With regard to the former aspect the following cases of study are described: production of enzymes, such as lipase by Candida cylindracea NRRL Y-17506, laccase and Mn-dependent peroxidase by Panus tigrinus CBS 577.79 and pectinases by Cryptococcus albidus var. albidus IMAT 4735, and exopolysaccharide production by Botryosphaeria rhodina DABAC-P82. As far as agronomic use of the waste is concerned, a process based on the acidogenic fungus Aspergillus niger NB2 and aimed at increasing the phosphorus content of OMW is also reported. Copyright © 2006 Society of Chemical Industry [source] Effect of Iron(III) Chitosan Intake on the Reduction of Serum Phosphorus in RatsJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 7 2000JOSEPH BAXTER Because of the widespread use of aluminium- and calcium-containing phosphate binders for the control of hyperphosphataemia in patients with end-stage renal failure, an iron(III) chitosan complex was synthesised and fed to rats to measure its effect on serum phosphorus and calcium, intestinal phosphate binding and phosphate absorption. Thirty-six Wistar rats were randomly selected and distributed into a baseline group (n = 6), a control group (n = 8 (days 0,15), n = 8 (days 16,30)) and a treatment group (n = 8 (days 0,15), n = 8 (days 16,30)). The control groups ingested AIN-76 diet mix with a 1% w/w fibre content; however, the treatment groups had the fibre content completely substituted with iron(III) chitosan. The mean weights of the treated rats were slightly lower from 15 days (not significant); but overall, rat growth was not stunted in the treatment groups. The serum phosphorus levels of the treated group (n = 8) were significantly reduced after 15 days (P = 0.004; control: 5.7 ± 0.9 mg dL,1; treatment: 4.4±0.5 mg dL,1; 95% CI of difference: 0.5,2.2) and 30 days (P = 0.002; control: 5.5 ± 0.9 mg dL,1; treatment = 4.1 ± 0.6 mg dL,1; 95% CI of difference: 0.6,2.3) as compared with the respective control group. The serum calcium-phosphorus product was 62.0 ± 12.1 mg2 dL,2 for the control and 45.1 ± 6.6 mg2 dL,2 for the treatment group after 30 days (P = 0.004). The serum iron concentration of the treatment group did not differ from the baseline value after 15 and 30 days, but the treatment group was significantly higher than the control group (P < 0.05) after 30 days. The faeces phosphorus levels (mg day,1) were higher (P < 0.01) and its iron content was much higher (P < 0.01) for the treated group. The urine phosphorus (mg kg,1) was not significantly reduced for the treated group, but the mean was consistently less. The kidney and liver weights of both groups were similar, but the phosphorus content of the kidney (mg (g kidney),1) was higher for the treated group after 30 days (P = 0.041; control, 4.2 ± 1.2 mg g,1 vs treatment, 5.6 ± 1.4 mg g,1. Because iron(III) chitosan had a high phosphorus-binding capacity of 308 (mg P) per gram of Fe3+ for both the in-vitro (pH 7.5) and in-vivo studies, which is greater than nearly all commonly used phosphate binders, and a small net phosphorus absorption difference of 3.7 mg day,1, it is an efficient phosphate binder for lowering serum phosphate levels without increasing serum calcium levels. [source] NITROGEN LIMITATION EFFECTS OF DIFFERENT NITROGEN SOURCES ON NUTRITIONAL QUALITY OF TWO FRESHWATER ORGANISMS, SCENEDESMUS QUADRICAUDA (CHLOROPHYCEAE) AND SYNECHOCOCCUS SP. (CYANOPHYCEAE)JOURNAL OF PHYCOLOGY, Issue 5 2003Gunnel Ahlgren Food quality for grazers has been related to mineral (nitrogen, phosphorus) and biochemical (amino acids, fatty acids) constituents. The aim of the study was to examine the influence of different nitrogen sources on these constituents in two organisms, the green alga Scenedesmus quadricauda Turp. and the cyanobacterium Synechococcus sp., commonly used in feeding experiments. The two organisms were grown in continuous cultures at different growth rates. Nitrate or ammonium salts were used as nitrogen sources under both replete and limited conditions. Carbon content (mg·g,1 dry weight) was stable in both organisms independent of nitrogen source, nitrogen limitation, and growth rate. Nitrogen content decreased with limitation and growth rate in Scenedesmus and to a lesser degree in Synechococcus, whereas changes in phosphorus content were not statistically significant. The relative proportions of amino acids (% of total amino acids) were relatively stable in both organisms, whereas the proportions of fatty acids varied with growth rate and limitation. Fatty acid content was much lower in Synechococcus than in Scenedesmus. At N limitation, polyunsaturated fatty acids (PUFAs) showed lower levels in both organisms. The change occurred in the ,3 PUFA (linolenic acid) of the green alga and in the ,6 PUFA (linoleic acid) of the cyanobacterium. The difference in the response of N limitation in the two organisms may be traced to the different composition of the chloroplast membranes (the prokaryotic way) and the microsomal membranes (the eukaryotic way) where the desaturation takes place. [source] Effect of the organophosphate structure on the physical and flame-retardant properties of an epoxy resinJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 3 2002Jeng-Yueh Shieh Abstract 2-(6-Oxido-6H-dibenzo,c,e,,1,2,oxa-phosphorin-6-yl)1,4-benzenediol (ODOPB) and bis(3-dihydroxyphenyl) phenyl phosphate (BHPP) were successfully synthesized and used as reactive flame retardants in o -cresol formaldehyde novolac epoxy resin. Because of the rigid, cyclic, side-chain structure of ODOPB, the resultant phosphorus-containing epoxy resin exhibited a higher glass-transition temperature, better flame retardancy, higher modulus, and greater thermal stability than the regular bromine-containing tetrabromobisphenol A epoxy resin and the linear, main-chain, phosphorus-containing BHPP epoxy resin. A UL-94VO rating was achieved with a phosphorus content as low as 1.1% with ODOPB (comparable to a bromine content of 12% and a phosphorus content of 2.2% with BHPP) in the cured resins, and no fumes or toxic gas emissions were observed. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 40: 369,378, 2002 [source] Selection of Leucaena species for afforestation and amelioration of sodic soilsLAND DEGRADATION AND DEVELOPMENT, Issue 5 2002V. L. Goel Abstract Performance of three exotic species of Leucaena (L. diversifolia, L. shannonii and L. leucocephala) and one local selection of L. leucocephala was evaluated on sodic soil sites (pH 8.6,10.5) in order to select promising species for biomass production and reclamation of these soils. There were significant differences among three species with respect to their field survival (47.7,95.5 per cent), growth in terms of stem volume (40.8,118.6,m3,ha,1) and biomass production (24,70,Mg,ha,1) after eight years of growth. L. leucocephala was rated as the most promising species irrespective of seed source, followed by L. shannonii. L. diversifolia could not perform well on these hostile soils. A definite improvement in physicochemical properties of soil particularly in surface layers (0,5,cm) was observed after eight years of plantations as compared to the same at uncultivated site. The soil pH and sodium content decreased followed by an increase in organic carbon, nitrogen and phosphorus content. However, efficiency of different species varied greatly to ameliorate these soils depending on quantity and quality of organic matter lying on the floor. L. leucocephala, irrespective of seed origin, showed greater promise for afforestation of sodic soils because of its potential to produce higher biomass per unit area and greater efficiency to ameliorate fertility status of these soils. The study revealed that matching of species to soil conditions is very important for a successful plantation programme and sustainable development of degraded soil sites. Copyright © 2002 John Wiley & Sons, Ltd. [source] Extending the retention of friction-reducing capability in low-phosphorus engine oilsLUBRICATION SCIENCE, Issue 2 2005R. Jensen Abstract In advanced fuel-efficient engine oils containing molybdenum dialkyldithiocarbamate, Mo(dtc)2, as a friction-reducing additive, the friction-reducing capability is gradually depleted with mileage accumulation and is dependent on the presence of other additives, such as zinc dialkyldithiophosphate, Zn(dtp)2. Indeed, it has been shown that the loss of the friction-reducing capability of Mo(dtc)2 coincides with the depletion of Zn(dtp)2. The next generation of oils will specify a lower phosphorus content (e.g., 0.08% in ILSAC GF-4 and even lower in the specification after GF-4) to reduce the detrimental effects of phosphorus on catalyst systems. This will necessitate the use of less Zn(dtp)2, which could have an adverse effect on the retention of friction-reducing capability. The aim of this study was to determine if the retention of friction-reducing capability could be maintained or even increased at 0.05% phosphorus with newer molybdenum trinuclear, Mo3S7(dtc)4, additives. To facilitate the study, a modified laboratory-based ageing test was developed which correlated with the loss of friction-reducing capability in the Sequence VIB engine test. This ageing test was used to evaluate model blends of Mo3S7(dtc)4 with Zn(dtp)2 at 0.05% phosphorus and added antioxidants. The results indicate that it is possible to extend the retention of friction-reducing capability. However, whether or not it can be extended beyond the current drain intervals is still an open question. [source] Synthesis, Characterization and Ionic Conductive Properties of Phosphorylated Chitosan MembranesMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 5-6 2003Ying Wan Abstract Phosphorylated chitosan membranes were prepared from the reaction of orthophosphoric acid and urea on the surface of chitosan membranes in N,N -dimethylformamide. Their ionic conductivity in the wet state was investigated. Chemical modifications contributed to improved ionic conductivities of the chitosan membranes. Compared to the unmodified chitosan membranes, it was found that hydrated phosphorylated chitosan membranes with an appropriate phosphorus content showed an increasing ionic conductivity of about one order of magnitude. The phosphorylation reaction mechanism was explained based on 13C and 31P NMR measurements. It was also observed that the crystallinity of the phosphorylated chitosan membranes and the corresponding swelling indices were changed pronouncedly, but these membranes did not lose either their tensile strength or thermal stability to a significant degree in comparison with the unmodified chitosan membranes. Possible reaction mechanism for preparation of phosphorylated chitosan membranes. [source] Boron nitride phosphide thin films grown on quartz substrate by hot-filament and plasma-assisted chemical vapor depositionPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 13 2004X. W. Zhang Abstract Boron nitride phosphide films are, for the first time, grown on transparent quartz substrate by hot filament and radio-frequency plasma co-assisted chemical vapor deposition technique. XPS, XRD, SEM, and UV measurements are performed to study the chemical composition, crystallization, microstructure, and optical absorption, respectively. A "centipede-like" microstructure and undulating ground morphology on the film surface are observed, and their growth mechanism is speculated upon. The chemical composition is determined as BN1,xPx, whose characteristic XRD peak is preliminarily identified. The optical band gap can be modulated between 5.52 eV and 3.74 eV, simply by adjusting the phosphorus content in BN1,xPx through modifying the PH3 flux during the film-deposition process. The merits of the BN1,xPx film, such as high ultraviolet photoelectric sensitivity with negligible sensitivity in the visible region, modifiable wide optical band gap, and good adhesion on transparent substrate, suggest potential applications for ultraviolet photo-electronics. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Phosphorus sources and availability modify growth and distribution of root clusters and nodules of native Australian legumesPLANT CELL & ENVIRONMENT, Issue 7 2002M. A. Adams Abstract A variety of native Western Australian legumes produced root clusters in sand culture confirming field and published observations. In general, these legumes grew equally well when supplied with organic or inorganic sources of phosphorus. The nitrogen content of shoots and roots varied little among treatments for all species, however, phosphorus content was always greater in plants supplied with inositol-P. The plasticity of root growth in response to localized placement of organic and inorganic sources of phosphorus was demonstrated using a simple ,split root' technique. Total root dry weight was, on average, more than doubled in P-amended sand when compared with non-amended sand. Root clusters tended to be produced in areas of relatively high phosphorus concentration and nodules in areas of low phosphorus concentration. Levels of phosphorus in lateral roots grown in P-amended sand were significantly different from lateral roots grown in the corresponding non-amended sand. Growth increases averaging 70% for white sand to over 100% for yellow sand indicated a large degree of ,plasticity' in roots under conditions of heterogeneous supply of phosphorus. Spatially exclusive development of organs for the acquisition of nutrients is discussed in relation to requirements for carbon in organ production and maintenance. [source] Fireproofing of polyurethane elastomers by reactive organophosphonatesPOLYMER INTERNATIONAL, Issue 1 2003Wassef El Khatib Abstract Polyurethane elastomers were prepared with hydroxytelechelic polybutadiene (HTPB) as polyol, modified 4,4,-diphenylmethane diisocyanate (modified MDI) as liquid polyisocyanate, and phosphonate diols as chain extenders and flame retardant compounds. These phosphonate diols were synthesized by radical thiol,ene addition of allyl or vinyl dialkyl phosphonate to 3-mercapto-1,2-propanediol. For various percentages of phosphorus (0 to 3%, w/w), polyurethane elastomers remain stable up to 250,°C. The percentage of residual char at 600,°C increases with increasing phosphorus content. For the soft segments, no variation in the glass transition temperature (Tg) is observed as the percentage of P increases, whereas the Tg of hard segments increases. Above 0.5% phosphorus content, the limiting oxygen index (LOI) becomes higher than the percentage of oxygen in the air. © 2003 Society of Chemical Industry [source] Nutrient transport within and between habitats through seed dispersal processes by woolly monkeys in north-western AmazoniaAMERICAN JOURNAL OF PRIMATOLOGY, Issue 11 2010Pablo R. Stevenson Abstract The contribution of vertebrate animals to nutrient cycling has proven to be important in various ecosystems. However, the role of large bodied primates in nutrient transport in neotropical forests is not well documented. Here, we assess the role of a population of woolly monkeys (Lagothrix lagothricha lugens) as vectors of nutrient movement through seed dispersal. We estimated total seed biomass transported by the population within and between two habitats (terra firme and flooded forests) at Tinigua Park, Colombia, and quantified potassium (K), phosphorus (P) and nitrogen (N) content in seeds of 20 plant species from both forests. Overall, the population transported an estimated minimum of 11.5 (±1.2 SD),g of potassium, 13.2 (±0.7),g of phosphorus and 34.3 (±0.1),g nitrogen, within 22.4 (±2.0),kg of seeds ha,1,y,1. Approximately 84% of all nutrients were deposited in the terra firme forest mostly through recycling processes, and also through translocation from the flooded forest. This type of translocation represents an important and high-quality route of transport since abiotic mechanisms do not usually move nutrients upwards, and since chemical tests show that seeds from flooded forests have comparatively higher nutrient contents. The overall contribution to nutrient movement by the population of woolly monkeys is significant because of the large amount of biomass transported, and the high phosphorus content of seeds. As a result, the phosphorus input generated by these monkeys is of the same order of magnitude as other abiotic mechanisms of nutrient transport such as atmospheric deposition and some weathering processes. Our results suggest that via seed dispersal processes, woolly monkey populations can contribute to nutrient movement in tropical forests, and may act as important nutrient input vectors in terra firme forests. Am. J. Primatol. 72:992,1003, 2010. © 2010 Wiley-Liss, Inc. [source] Dietary magnesium did not affect calcium and phosphorus content in juvenile grouper, Epinephelus coioidesAQUACULTURE NUTRITION, Issue 4 2010C.-X. YE Abstract Most of magnesium (Mg) in fish is located in the bone. Dietary calcium (Ca) and phosphorous (P) has been reported to affect scales and vertebrae Mg dramatically in juvenile grouper, but the effect of dietary Mg on tissue Ca and P is unknown. This study was conducted to investigate the effect of dietary Mg supplement on growth, feed efficiency, morphometry, and the ash and Ca, P, sodium (Na) content in scales and vertebrae of juvenile grouper. Seven experimental diets were formulated to contain graded levels of Mg by supplementing the basal diet with 0, 200, 400, 600, 800, 1000 and 2000 mg kg,1 Mg in the form of Mg sulphate (MgSO4·7H2O). Juvenile grouper with an initial body weight of 11.8 ± 0.1 g were fed to apparent satiation twice per day for 10 weeks. Dietary Mg supplement had no significant effect on growth, feed efficiency, and Mg concentration in scales and vertebrae of grouper, which indicates the Mg requirement of grouper was met in fish fed the basal diet. Mg supplements had significant effect on morphometry index such as body length, condition factor, viscera somatic index and mesenteric fat index. Extra dietary Mg supplement to the basal diet had no negative effect on ash, Ca and P concentrations in scales and vertebrae. [source] Phosphorus requirement of Catla (Catla catla Hamilton) fingerlings based on growth, whole-body phosphorus concentration and non-faecal phosphorus excretionAQUACULTURE RESEARCH, Issue 2 2009Krishna Sukumaran Abstract A 120-day feeding trial was conducted to determine the dietary requirement of phosphorus for Indian major carp, catla (Catla catla) fingerlings. Four hundred and eighty fingerlings (mean body weight: 4.23±0.87 g) were randomly distributed among eight treatment groups with three replicates each. Eight isonitrogenous and isocaloric semi-purified diets (crude protein: 35% and crude lipid: 8.5%) were formulated with graded levels of phosphorus using KH2PO4 (T1: control, 0.1%; T2: 0.3%; T3: 0.5%; T4: 0.7%; T5: 0.9%; T6: 1.1%; T7: 1.3%; T8: 1.5%) and fed to the respective groups. Twenty fish were stocked in 150 L plastic tanks and fed to apparent satiation twice a day. Specific growth rate (SGR) significantly (P<0.05) increased with increasing dietary phosphorus concentration from 0.73% to 1.27%, after which there was a slight decline in growth at 1.1% available phosphorus (aP) and remained constant thereafter. The quadratic broken-line model based on growth was Y=317.5,581(0.64,x) (0.64,x); R2=0.73. Moisture and crude protein contents of whole body were similar among all the treatments. However, the ether extract in T1 group was significantly (P<0.05) higher than all the other treatments. The whole-body phosphorus content increased significantly (P<0.05) with an increase in phosphorus in the diets. The one-slope broken-line model based on whole-body phosphorus concentration was Y=4.07,1.63 (0.71,x); R2=0.48. The one-slope broken-line model for non-faecal phosphorus excretion as inorganic phosphorus (Pi) for 24 h revealed a trend of Y=12.67+73.96 (x,0.6); R2=0.81. Minimum aP requirements based on weight gain (%), whole-body phosphorus content and phosphorus excretion were 0.64%, 0.71% and 0.6%, respectively. Hence, the dietary aP requirement of catla fingerlings ranges from 0.6% to 0.71%. [source] Phosphorus requirements of gilthead sea bream (Sparus aurata L.) juvenilesAQUACULTURE RESEARCH, Issue 2001A M Pimentel-Rodrigues Abstract A trial was conducted to evaluate the phosphorus requirements of gilthead sea bream juveniles. Seven semipurified diets were formulated to contain 54% crude protein and 15% lipids and phosphorus (di-calcium phosphate) levels ranging from 0.37% to 1.5% (DM basis). Each diet was fed to duplicate groups of 25 fish with an initial average weight of 5 g over 42 days. The fish were fed by hand to visual apparent satiety twice daily, six days a week. At the end of the trial growth rate was not significantly different in groups fed diets containing 0.75% phosphorus or higher, while growth rate of fish fed the 0.37% phosphorus diet was significantly lower than all the other diets. Feed efficiency ratio, protein efficiency ratio and N retention were significantly lower in fish fed the 0.37% phosphorus diet than in those fed diets with 0.75% and higher phosphorus levels. Phosphorus content of the fish averaged 2% (on a dry weight basis) and was not significantly affected by dietary phosphorus content. Phosphorus retention averaged 6.6 g kg,1 weight gain and was not statistically different among groups. Phosphorus retention (% phosphorus intake) decreased with the increase of dietary phosphorus content, being even higher than 100% in groups fed diets with 0.37% and 0.57% phosphorus, indicating phosphorus absorption from the water. The results of this study indicate that phosphorus requirements of gilthead sea bream juveniles were satisfied with a diet including 0.75% phosphorus. [source] Feeding rates, assimilation efficiencies and growth of two amphipod species on biodeposited material from zebra musselsFRESHWATER BIOLOGY, Issue 12 2008RENÉ GERGS Summary 1. Accumulation of organic material by the zebra mussel Dreissena polymorpha is assumed to be the source of a biodeposition-based food web. However, only little is known about the importance of the biodeposited material as a food source and its contribution to increased abundances of macroinvertebrates in the presence of D. polymorpha. 2. Feeding, assimilation and growth of the amphipods Gammarus roeselii and Dikerogammarus villosus on food sources directly and indirectly associated with D. polymorpha (biodeposited material and chironomids) and on conditioned alder leaves were measured. The stoichiometry of carbon, nitrogen and phosphorus of the diets was measured as an important determining factor of food quality. 3. Chironomids had the highest nitrogen and phosphorus contents, alder leaves were depleted in nitrogen and phosphorus, and the stoichiometry of biodeposited material was intermediate. 4. Both amphipod species had highest feeding rates and assimilation efficiencies on chironomids. Gammarus roeselii fed more on biodeposited material than on alder leaves, but assimilation efficiencies were similar; D. villosus also had similar feeding rates and assimilation efficiencies on the two diets. 5. Both amphipod species had highest growth rates on chironomids and lowest growth rates on alder leaves. Both grew at intermediate rates on biodeposited material of D. polymorpha. The growth rates of the amphipod species were related to food stoichiometry. Overall, the invasive D. villosus grew faster than the indigenous G. roeselii. 6. Food resources directly and indirectly associated with D. polymorpha are potential diets for amphipods, providing further evidence for a D. polymorpha biodeposition-based food web. [source] Breakdown of wood in the Agüera streamFRESHWATER BIOLOGY, Issue 11 2002Joserra Díez SUMMARY 1. Breakdown of wood was compared at three sites of the Agüera catchment (Iberian Peninsula): two oligotrophic first-order reaches (one under deciduous forest, the other under Eucalyptus globulus plantations) and one third-order reach under mixed forest, where concentration of dissolved nutrients was higher. 2. Branches (diameter = 3 cm, length = 10 cm) of oak (Quercus robur), alder (Alnus glutinosa), pine (Pinus radiata) and eucalyptus, plus prisms (2.5 × 2.5 × 10 cm) of alder heartwood were enclosed in mesh bags (1 cm mesh size) and placed in the streams. Mass loss was determined over 4.5 years, whereas nutrient, lignin and ergosterol were determined over 3 years. In order to describe fungal dynamics, ergosterol was also determined separately on the outer and inner parts of some branches. 3. Breakdown rates ranged from 0.0159 to 0.2706 year,1 with the third-order reach having the highest values whatever the species considered. The most rapid breakdown occurred in alder heartwood and the slowest in pine branches; breakdown rates of oak, eucalyptus and alder branches did not differ significantly. 4. The highest nitrogen and phosphorus contents were found in alder, followed by oak, while pine and eucalyptus had low values. During breakdown, all materials rapidly lost phosphorus, but nitrogen content remained constant or slightly increased. Lignin content remained similar. 5. Peaks of ergosterol ranged from 0.023 to 0.139 mg g,1 and were higher in alder than in other species in two of the three sites. The third-order reach generally had the greatest increase in ergosterol, especially in alder branches, eucalyptus and alder heartwood. The overall species/site pattern of fungal biomass was thus consistent with the observed differences in breakdown. 6. When compared with leaves of the same species decomposing at these sites, wood breakdown appeared to be less sensitive to the tree species but more sensitive to stream water chemistry. Although wood breakdown is slower and its inputs are lower than those of leaf litter, its higher resistance to downstream transport results in a relatively high standing stock and a significant contribution to the energy flux. [source] Seasonal changes in herbage production and soil phosphorus contents in Japanese lawngrass (Zoysia japonica Steud.) and tall fescue (Festuca arundinacea Schreb.) pasturesGRASSLAND SCIENCE, Issue 1 2008Makoto Kaneko Abstract Seasonal changes in the above-ground phosphorus (P), soil total P (TP), soil Olsen P (OP) and soil microbial biomass P (MBP) were investigated for 2 years in Japanese lawngrass (Zy) and tall fescue (Tf) pastures on Japanese Andosol, with the goal of clarifying P characteristics in the Zy pasture in comparison with the Tf pasture. The soil P attributes were measured in two soil layers (root mat layer, 0,2.5 cm depth; under layer, 5,10 cm depth). The P concentration of the above-ground herbage in the Zy pasture, which was higher than the standard value and similar to those in the Tf pasture, might have contributed to the large amounts of the above-ground P mass. The lack of plowing management and the coverage with Japanese lawngrass might have changed soil TP. The TP, the OP and the OP/TP in the Zy pasture were higher than those in the Tf pasture, and the TP, the OP and the OP/TP at the root mat layer were higher than those at the under layer. A large amount of the TP and high P availability in the soil caused the large amounts of OP. Soil pH, soil microorganisms and MBP might have affected soil P availability in the Zy pasture. Plant litter in the root mat layer of the Zy pasture may have increased soil P accumulation and its availability, which might be reasons for the high P uptake in the present study. Japanese lawngrass pasture may be a system with improved soil P utilization efficiency based on P cycling. [source] Physicochemical Properties of Starches Obtained from Three Varieties of Chinese Sweet PotatoesJOURNAL OF FOOD SCIENCE, Issue 2 2003Z. Chen ABSTRACT: Starches isolated from 3 typical types of Chinese sweet potato varieties (XuShu18, SuShu2, and SuShu8) were characterized and compared with starches isolated from potato and mung bean. The 3 sweet potato starches differed in granule size; particle size distribution; protein, lipid, and phosphorus contents; pasting behaviors; swelling patterns; and syneresis. The retrogradation tendencies, measured both by setback ratio and by syneresis, differed for the 3 starches, although the amylose contents were quite similar (19.3 to 20.0%). Physicochemical properties of all 3 types of starches are evidently different from each other and from those of potato and mung bean starches. Keywords: sweet potato, starch, gelatinization, retrogradation, swelling, syneresis [source] Cathodoluminescence as a tool to determine the phosphorus concentration in diamondPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 9 2007J. Barjon Abstract In n-type diamond doped with phosphorus, exciton properties have been investigated by cathodoluminescence as a function of the phosphorus concentration. A series of homoepitaxial diamond layers were grown by microwave plasma-assisted chemical vapor deposition and doped with a liquid organic precursor of phosphorus (tertiarybutylphosphine). Their phosphorus concentration ranges from 5.2 × 1016 cm,3 to 3.3 × 1018 cm,3 as measured by secondary ion mass spectrometry. It is shown that the ratio between the luminescence intensities of the neutral phosphorus-bound exciton and the free exciton recombinations follows the donor concentration. A calibration graph is presented to determine the phosphorus contents in diamond with cathodoluminescence spectroscopy at 102 K. The influence of electrical compensation on the optical spectra is discussed. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] ICP,MS ANALYSIS OF GLASS FRAGMENTS OF PARTHIAN AND SASANIAN EPOCH FROM SELEUCIA AND VEH ARDA,?R (CENTRAL IRAQ)*ARCHAEOMETRY, Issue 3 2008P. MIRTI Forty-one glass fragments were analysed by inductively coupled plasma , mass spectrometry, determining 40 major, minor and trace elements, including rare earth elements. The fragments came from excavations carried out at the archaeological sites of Seleucia and Veh Arda,?r in modern Iraq, and were dated to the Parthian and Sasanian epochs. Analytical data indicate that all the samples are silica,soda,lime glasses. Magnesium and potassium oxide contents below 1% suggest that eight out of nine glasses from Seleucia, dating from between the first and the third century ad, could have been obtained by use of an evaporite as a flux; the same conclusion can be drawn for some of the Sasanian glasses dating from the fourth and fifth centuries ad. The other glasses from Veh Arda,?r, as well as the remaining sample from Seleucia, are characterized by higher contents of magnesium and potassium, which suggests recourse to plant ash; different magnesium and phosphorus contents allow one to separate these samples into two main groups, pointing to the use of different kinds of plant ash. Aluminium and calcium contents, together with trace element data, may indicate that different sands were used for preparing glasses of different composition. Samples from Seleucia and Veh Arda,?r are mainly blue,green and green to yellow,green, respectively; iron and manganese contents suggest that the furnace atmosphere was mainly responsible for the development of these hues. [source] Mineralogical And Chemical Investigations Of Bloomery Slags From Prehistoric (8th Century Bc To 4th Century Ad) Iron Production Sites In Upper And Lower Lusatia, GermanyARCHAEOMETRY, Issue 2 2001R. B. Heimann More than 400 fayalitic bloomery slags from prehistoric iron production sites in Upper and Lower Lusatia, eastern Germany, as well as bog iron ore samples and intermediary samples of the smelting process, were analysed by chemical and mineralogical techniques. While the precursor bog iron ores exploited in the two regions under investigation were very similar in composition, consisting of low-manganese/low-barium as well as high-manganese/high-barium types of ore, pronounced differences in slag composition were detected. Slags from 17 investigated sites in Upper Lusatia showed average P2O5 contents between 1 and 3 mass%, whereas slags from 15 investigated sites in Lower Lusatia were generally much richer in phosphorus, reaching values as high as 7 mass% P2O5. Since a reasonable correlation exists between calcium and phosphorus contents in the slags of the latter sites, it is conjectured that deliberate addition of CaO to the ore/charcoal charge of the bloomery furnace may have taken place in order to fix the phosphorus in the slags effectively. In many samples, this conjecture is being supported by the detection of a slag mineral Ca,Fe phosphate Ca9,xFe1+x(PO4)7 that presumably crystallized from a residual phosphorus-rich melt and shows a cotectic relationship to both Ca-rich fayalite and wustite, as well as to members of the solid solution series magnetite,hercynite. [source] | ||||||||||||||||||||||