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Growth Parameters (growth + parameter)
Selected AbstractsDisruptiveness, peer experiences and adolescent smoking: a long-term longitudinal approachADDICTION, Issue 4 2009Roy Otten ABSTRACT Aims This study examined links of peer experiences (i.e. social status and affiliation with disruptive peers) throughout childhood with respect to adolescent smoking trajectories, after controlling for childhood disruptiveness. Specifically, we tested four models regarding links of peer experiences and deviant behaviours. Design Prospective community sample. Participants A total of 312 children, aged 6.17 years at baseline. Measurements Growth parameters of own disruptive behaviour, disruptive behaviour of friends and social status measured at ages 7,12 years as predictors of smoking assessed at ages 13,15 years, while controlling for own disruptive behaviour at age 6 years. Findings We found three groups with distinct profiles of smoking. One group displayed hardly any or no smoking at all; a second group showed a trajectory of increased smoking; and a third group that showed high smoking rates initially and increased in smoking intensity over time. Results support the assumption of the selection model that the link between disruptive peers and smoking is spurious and due to shared variances with own early disruptiveness. Moreover, support was found for the popularity,socialization model supporting the assumption that age-related increases in social status are associated with smoking. Conclusions The findings emphasize that early disruptiveness is predictive of later smoking. In addition, it was shown that smoking becomes less deviant over time, in line with group norms. Future prevention programmes should emphasize the need to change these norms. [source] Basic characteristics of the population dynamic and state of exploitation of Moroccan white seabream Diplodus sargus cadenati (Sparidae) in the Canarian archipelagoJOURNAL OF APPLIED ICHTHYOLOGY, Issue 1 2004J. G. Pajuelo Summary Moroccan white seabream Diplodus sargus cadenati (n = 603) were caught off the Canary Islands from April 2000 to March 2001. Total length ranged from 46 to 404 mm. The subspecies was characterized as being dygynous with partial protandry. Overall ratio of males to females was 1 : 2.9. The reproductive season extended from December to May, with a peak in spawning activity in January,February. Fifty per cent maturity was reached at 201 mm total length in males and 216 mm in females. The length,weight relationship for all individuals was described by the following parameters: a = 0.000023, and b = 2.96, when length is given in millimeters and weight in grams. Fish of 0,12 years in age were found. The von Bertalanffy growth parameters for the entire population were: L, = 467 mm, k = 0.143 year,1 and t0 = ,2.14 year. Growth parameters differed between males and females. For all fish, instantaneous rates of mortality were Z = 0.68 year,1, M = 0.31 ± 0.6 year,1 and F = 0.37 ± 0.6 year,1; the exploitation ratio was E = 0.54 ± 0.9. Length at first capture for all individuals was 173 mm. The stock exploited above is an assumed optimum. [source] Protein intake, growth and lung function of infants with chronic lung diseaseJOURNAL OF HUMAN NUTRITION & DIETETICS, Issue 3 2009E. Cillié Background:, The increased survival rate of extremely preterm infants has not improved the incidence or outcome of infants diagnosed with chronic lung disease (CLD) (Riley, 2008). The relationship between optimal nutrition (particularly protein intake) and chronic lung disease has not been established. The aim of this study was to investigate the association between protein intake, growth and lung function in infants with CLD. Methods:, A CLD database, maintained for the past 10 years, was used to select participants that had reached 1 year of corrected age. Infants who were born during 2001,2006 with a birth weight of <1500 g, and who subsequently had a diagnosis of CLD, were included. Infants with evidence of intra-uterine growth restriction and abnormal cerebral pathology were excluded. Demographic, mean weight gain, protein intake and respiratory support data were collected retrospectively from the medical notes. Growth parameters and need for oxygen and inhalers up to 1 year of corrected age were collected from the CLD follow-up database. SPSS, version 15 (SPSS Inc., Chicago, IL, USA) were used for Pearson's or Spearmans correlation analysis and analysis of variance or the Wilcoxon test, as appropriate. Results:, Sixty infants were studied: 25 females and 35 males. The median (range) post-menstrual age at birth was 26 (22,31) weeks. The most common feed was breast milk; fortified breast milk was used for 37% of the total days studied. The mean (SD) protein intake was 2.28 (0.33) g kg,1 day,1 and the mean (SD) weight gain was 11.67 (1.77) g kg,1 day,1. There was a positive correlation between protein intake and weight gain (r = 0.32, P = 0.013), which was stronger in females (r = 0.51, P = 0.009). Protein intake was significantly associated with head circumference growth in females only (r = 0.47, P = 0.038). Protein intake was inversely related to the number of days spent mechanically ventilated (r = ,0.32, P = 0.015). There was no relationship between protein intake and growth at 1 year corrected age, time spent on continuous positive airway pressure, age weaned off oxygen, or the use of inhalers. There was an inverse correlation between total weeks of oxygen dependence and head circumference at 1 year (r = ,0.35, P = 0.022). Discussion:, The mean protein intake was <3 g kg,1 day,1, which is the minimum requirement for preterm infants (Tsang et al., 2005). This was associated with a sub-optimal weight gain in our participants of <15 g kg,1 day,1 (Steward & Pridham, 2002). The study demonstrates the known association between low protein intake and poor growth with ventilator dependence (Loui et al., 2008). Conclusions:, Low birth weight and low gestational age infants at risk of CLD should receive special attention to optimise their protein intake because sub-optimal protein intake potentially leads to poor growth when on a neonatal intensive care unit. References Loui, A., Tsalikaki, E., Maier, K., Walch, E., Kamarianakis, Y. & Obladen, M. (2008) Growth in high risk infants <1500 g birth weight during the first 5 weeks. Early Hum. Dev. 84, 645,650, Doi: 10.1016/j.earlhumdev.2008.04.005. Riley, K., Roth, S., Sellwood, M. & Wyatt, J.S. (2008) Survival and neurodevelopmental morbidity at 1 year of age following extremely preterm delivery over a 20-year period: a single centre cohort study. Acta Paediatr.97, 159,165. Steward, D.K. & Pridham, K.F. (2002) Growth patterns of extremely low-birth-weight hospitalised preterm infants. JOGN Nurs31, 57,65. Tsang, R.C., Uauy, R., Koletzko, B. & Zlotkin, S.H., eds. (2005) Nutrition of the Preterm Infant: Scientific Basis and Practical Guidelines. Cincinnati: Digital Educational Publishing. [source] Effects of calcium supplementation on fetal growth in mothers with deficient calcium intake: a randomised controlled trialPAEDIATRIC & PERINATAL EPIDEMIOLOGY, Issue 1 2010Edgardo Abalos Summary Abalos E, Merialdi M, Wojdyla D, Carroli G, Campodónico L, Yao S-E, Gonzalez R, Deter R, Villar J, Van Look P. Effects of calcium supplementation on fetal growth in mothers with deficient calcium intake: a randomised controlled trial. Paediatric and Perinatal Epidemiology 2010; 24: 53,62. Calcium supplementation in mothers with low calcium intake has been of interest recently because of its association with optimal fetal growth and improved pre-eclampsia-related outcomes. While the effects of calcium supplementation have demonstrated benefits in prolonging gestation and subsequently improving birthweight, no specific studies have identified the longitudinal effects of supplementation on fetal growth in utero. Data were analysed in the context of the World Health Organization trial of calcium supplementation in calcium-deficient women. Five hundred and ten healthy, primiparous pregnant Argentinean women were randomised (at <20 weeks gestation) to either placebo (n = 230) or calcium supplements (1500 mg calcium/day in 3 divided doses; n = 231). Growth parameters in utero were assessed with serial ultrasound scans. Birthweight, length, head, abdominal and thigh circumferences were recorded at delivery. No differences were found in fetal biometric measurements recorded at 20, 24, 28, 32 and 36 weeks gestation between fetuses of women who were supplemented with calcium and those who were not. Similarly, neonatal characteristics and anthropometric measurements recorded at delivery were comparable in both groups. We conclude that calcium supplementation of 1500 mg calcium/day in pregnant women with low calcium intake does not appear to impact on fetal somatic or skeletal growth. [source] Prediction of adult stature for Japanese population: A stepwise regression approachAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 3 2001MD. Ayub Ali The longitudinal growth in stature for 509 males and 311 females was characterized from early childhood to adulthood. A triphasic generalized logistic (BTT) model (Bock et al. [1994] Chicago: SSI) was used through the AUXAL software program. Growth parameters were derived from the estimated distance and velocity curves for each individual. A set of estimated growth parameters, including adult stature, was selected to develop equations, through the forward stepwise regression method, for the prediction of adult stature for Japanese boys and girls. Am. J. Hum. Biol. 13:316,322, 2001. © 2001 Wiley-Liss, Inc. [source] Mutual influence of protein and lipid feed content on European catfish (Silurus glanis) growthJOURNAL OF APPLIED ICHTHYOLOGY, Issue 2 2004E. Has-Schön Summary We wished to determine protein and lipid content in pelleted raw fish food, necessary for optimal growth of European catfish (Silurus glanis). Experiments were set up in 20 cages, each holding 30 young catfish. Fishes in each cage received a different food combination over a 98-day period at favourable physical and chemical water conditions. Food protein content varied between 37.5 and 45%, while lipid content, added in the form of soybean oil, varied between 3 and 11%. The oil contained an adequate , -fatty acids concentration, necessary for fish growth. The main growth indicators determined at the end of experiment were total body gain, specific growth rate and feed conversion ratio. There was a high statistical difference among the experimental groups receiving variable food combinations for each growth parameter (P < 0.001). Both protein and lipid food content affected growth parameters, but in a different manner. Further analysis , percentage of change depending on lipid to protein ratio and bivariate surface analysis , allowed us to recognize the most economical combination: 39.5% protein + 9% lipid content. The addition of 9% soybean oil to the fish food reduces the necessary protein concentration by 5.5%, with resulting identical catfish growth effects. [source] A randomized trial of enteral feeding volumes in infants born before 30 weeks' gestationJOURNAL OF PAEDIATRICS AND CHILD HEALTH, Issue 6 2000C A Kuschel Objective: To compare the effect of two volumes of enteral feeds on postnatal growth in infants born before 30 weeks gestation. Methodology: Fifty-four infants, less than 30 weeks gestational age, who reached full enteral feeds were randomized to remain on 150 mL/kg per day (150 group) or increase to 200 mL/kg per day (200 group). The primary outcome measure was growth at 35 weeks corrected gestational age (CGA). Results: There were no statistically significant differences in demographic or clinical parameters between the study groups at commencement of the study, although there was a trend for infants in the 150 group to be lighter (895 g vs 1020 g, P = 0.27). Milk intakes were increased in 43% of the infants in the 150 group, whereas 54% of the infants in the 200 group required reduced intakes. Infants in the 200 group had greater daily weight gains (16.7 g/kg per day vs 15.2 g/kg per day, P = 0.047) and at 35 weeks CGA were heavier (2020 g vs 1885 g, P = 0.014) and had a greater arm fat area (282 mm2vs 218 mm2, P = 0.009). There was no difference in length or head circumference at 35 weeks CGA, and no difference in any growth parameter at 1 year of age. Morbidity was not different between the groups. Conclusions: The individual milk volume requirements for adequate weight gain without significant adverse effects vary between 150 and 200 mL/kg per day in extremely premature infants. For many infants in both groups, the assigned target volume was not appropriate. Increased milk intakes (and therefore higher caloric and mineral intakes) are associated with increased daily weight gains and a greater weight at 35 weeks CGA. The weight gain may be due to an increase in fat deposition. [source] CONSTANT EFFORT AND CONSTANT QUOTAFISHING POLICIES WITH CUT-OFFS IN A RANDOM ENVIRONMENTNATURAL RESOURCE MODELING, Issue 2 2001CARLOS A. BRAUMANN ABSTRACT. Consider a population subjected to constant effort or constant quota fishing with a generaldensity-dependence population growth function (because that function is poorly known). Consider environmental random fluctuations that either affect an intrinsic growth parameter or birth/death rates, thus resulting in two stochastic differential equations models. From previous results of ours, we obtain conditions for non-extinction and for existence of a population size stationary density. Constant quota (which always leads to extinction in random environments) and constant effort policies are studied; they are hard to implement for extreme population sizes. Introducing cut-offs circumvents these drawbacks. In a deterministic environment, for a wide range of values, cutting-off does not affect the steady-state yield. This is not so in a random environment and we will give expressions showing how steady-state average yield and population size distribution vary as functions of cut-off choices. We illustrate these general results with function plots for the particular case of logistic growth. [source] Reactivity of organosilicon precursors in remote hydrogen microwave plasma chemical vapor deposition of silicon carbide and silicon carbonitride thin-film coatingsAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 3 2010A. M. Wrobel Abstract A number of organosilicon precursors for silicon carbide and silicon carbonitride thin-film coatings, such as silanes, carbosilanes, aminosilanes, and disilazane, respectively, were characterized in terms of their reactivity in a remote microwave plasma chemical vapor deposition process, which was induced using hydrogen as plasma generating gas. The process displayed high selectivity with respect to the activating species and the chemical bonds in the molecular structure of the precursors. In view of very short life times of excited hydrogen plasma species the activation step takes place with an exclusive contribution of ground-state hydrogen atoms. The CH, CC, SiC, SiN, CN and NH bonds present in the molecules of the precursors are non-reactive and only the SiH or SiSi bonds play a key role in the activation step. The reactivity of the precursors was characterized in a quantitative way by the yield of the film growth parameter. The yield parameter expressing the mass of film per unit mass of the precursor fed to the reactor was calculated from the slopes of linear plots of time dependencies of film mass and precursor mass, which were determined for each investigated precursor. The reactivity of the precursors was found to be strongly dependent on the number of the SiH units present in their molecules and those containing two SiH units appeared to be most reactive. Copyright © 2009 John Wiley & Sons, Ltd. [source] Aggregation characteristics of ovalbumin in ,-sheet conformation determined by spectroscopyBIOPOLYMERS, Issue 2 2002Raimon Sabaté Abstract Protein misfolding and aggregation are involved in a number of the so-called "conformational" diseases (e.g., transmissible spongiform encephalopathies and Alzheimer disease). The development of rational strategies to interfere with aggregation is a potential therapeutic approach that requires complete knowledge of the aggregation process. We studied the aggregation of ovalbumin in ,-sheet conformation using mainly the spectral changes in the spectra of two dyes (Congo Red and pinacyanol) caused by the aggregates. We assumed a linear model of polymerization that fit to the experimental data. The critical aggregation constant, concentration of half-aggregation, nucleation parameter, growth parameter, and number of aggregation and free energy changes (total and per residue) were determined as aggregation-related parameters. ,-Ovalbumin aggregates in a cooperative way. Moreover, the differences between such parameters obtained with Congo Red and pinacyanol suggest that each dye interacts with the protein in its own way. © 2002 John Wiley & Sons, Inc. Biopolymers (Biospectroscopy) 67: 113,120, 2002 [source] Neurodevelopmental Outcomes in Infants after Surgery for Congenital Heart Disease: A Comparison of Single-Ventricle vs.CONGENITAL HEART DISEASE, Issue 2 2010Two-Ventricle Physiology ABSTRACT Introduction., The neurodevelopmental outcome of children with repaired congenital heart defect has risen in importance with improved survival. This study compares neurodevelopmental outcomes of children who had CHD with single ventricle physiology with those who had CHD with two-ventricle physiology. Patients and Methods., Participants included 112 infants discharged from the NICU between February 1999 to August 2006. The 12 infants who had a known genetic defect were excluded. Of the 100 infants 26 had single ventricle physiology and 74 had CHD with two-ventricle physiology. The children were seen in a follow-up clinic and growth parameters and standardized instruments were used to evaluate development. The referral rate to early intervention services was also compared. Results., The number of functional ventricles did not significantly differentiate growth parameters at 6,8 months of age. Early cognitive outcomes were relatively unimpaired in both the groups (single ventricle vs. two ventricle physiology). Early motor outcomes were worse in (p < 0.05) CHD with single ventricle physiology. The rate of referral for early intervention services was high in both groups compared to the average rate of referral in the state, but there was not a significant difference between the CHD groups. Conclusion., Significant differences noted on motor outcomes at the 6,8 month visit were no longer apparent in later visits. Referral to early intervention services is high in both the groups. These findings are important to those caring for infants with CHD because many of these patients may need referral for early intervention. [source] Three-dimensional study of the pressure field and advantages of hemispherical crucible in silicon Czochralski crystal growthCRYSTAL RESEARCH AND TECHNOLOGY, Issue 6 2010F. Mokhtari Abstract The effects of several growth parameters in cylindrical and spherical Czochralski crystal process are studied numerically and particularly, we focus on the influence of the pressure field. We present a set of three-dimensional computational simulations using the finite volume package Fluent in two different geometries, a new geometry as cylindro-spherical and the traditional configuration as cylindro-cylindrical. We found that the evolution of pressure which is has not been studied before; this important function is strongly related to the vorticity in the bulk flow, the free surface and the growth interface. It seems that the pressure is more sensitive to the breaking of symmetry than the other properties that characterize the crystal growth as temperature or velocity fields. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Nucleation kinetics and growth of nonlinear optical bis (dimethyl sulfoxide) manganese mercury thiocyanate single crystalsCRYSTAL RESEARCH AND TECHNOLOGY, Issue 10 2008C. M. Raghavan Abstract Nonlinear optical (NLO) material of bis (dimethyl sulfoxide) manganese mercury thiocyanate (MMTD) was synthesized by two step reaction method. The solubility and metastable zonewidth were experimentally determined in order to optimize the growth parameters. Bulk crystals of MMTD were grown by slow cooling and slow evaporation methods. The structure of the grown crystal was confirmed by X-ray diffraction analysis. Presence of functional groups and the coordination of Lewis base ligand of dimethyl sulfoxide (DMSO) were confirmed by FT-IR analysis. Optical transparency of the grown crystals was studied by UV-Vis spectroscopy. Nonlinear optical property of the grown crystal was confirmed by Kurtz powder method. Etching studies reveal the formation of triangular hillock etch patterns, indicative of 2D nucleation mechanism. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Nucleation kinetics and growth aspects of semi organic non-linear optical bis thiourea cadmium acetate single crystalsCRYSTAL RESEARCH AND TECHNOLOGY, Issue 9 2006R. Sankar Abstract Nucleation parameters such as metastable zone width, induction period and interfacial energy have been determined for the aqueous solution growth of bis thiourea cadmium acetate (BTCA) single crystals. Solubility of BTCA has been determined for various temperatures. Metastable zone width and induction period values have been estimated in order to optimize the growth parameters. The interfacial tension values derived from experimentally determined induction period are found to be comparable with theoretical values. Bulk crystals of BTCA have been grown using the optimized growth parameters. The grown crystals have been subjected to structural, optical and mechanical property studies. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Neurodevelopmental outcomes in children with HIV infection under 3 years of ageDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 8 2006C J Foster BA MBBS MRCPCH Following the introduction of combination antiretroviral therapy, children vertically infected with the human immunodeficiency virus (HIV-1) living in the developed world are surviving into adult life. This paper reviews the neurodevelopmental outcomes of 62 consecutively-presenting children with HIV-1 infection diagnosed before 3 years of age (32 males, 30 females; median age at presentation 6mo). Neurological and developmental data are presented with immunological and virological responses to antiretroviral therapy. Fourteen children (22%) had abnormal neurological signs and 25 (40%) demonstrated significant developmental delay on standardized developmental assessments. Children presenting with more severe HIV-1 disease and immune compromise had significantly more abnormal neurological signs and developmental delays than children presenting with milder HIV-1 symptomatology. Immune function, control of HIV-1 viral replication, and growth parameters improved with antiretroviral therapy (median age at last follow-up 7y 3mo); however, abnormal neurological signs and significant gross motor difficulties persisted. [source] Willow genotype, but not drought treatment, affects foliar phenolic concentrations and leaf-beetle resistanceENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 1 2004Carolyn Glynn Abstract In a greenhouse experiment we examined the effect of willow genotype and irrigation regime (moderate drought and well-watered) on plant growth parameters, foliar nitrogen, and phenolic concentrations, as well as on the preference and performance of the blue leaf beetle, Phratora vulgatissima (L.) (Coleoptera: Chrysomelidae). The 10 vegetatively propagated willow genotypes in the experiments were F2 full-sibling hybrids, originated from a cross between Salix viminalis (L.) (Salicaceae) (high in condensed tannins) and Salix dasyclados (L.) (Salicaceae) (rich in phenolic glycosides). Insect bioassays were conducted on detached leaves in Petri dishes as well as with free-living insects on intact potted plants. The 10-week long irrigation treatments caused statistically significant phenotypic differences in the potted willow saplings. Total biomass was somewhat higher in the well-watered treatment. The root to total biomass ratio was higher in the drought-treatment plants. There was significant genotypic variation in foliar nitrogen concentrations, and they were higher in the drought-treatment plants. There was also a strong genotypic variation in each of the phenolic substances analyzed. Condensed tannins, which accounted for the greatest proportion of total phenolic mass, were higher in the well-watered treatment. There was, however, no difference in levels of the other phenolics (salicylates, cinnamic acid, flavonoids, and chlorogenic acid) between irrigation treatments. The sum of these phenolics was higher in the well-watered treatment. There was a strong variation in P. vulgatissima larval development on different willow genotypes, and larval performance was negatively correlated with levels of salicylates and cinnamic acid. There was, however, no effect of irrigation treatment on larval performance. Phratora vulgatissima preferred to feed on well-watered plants, and we found a preference for oviposition there, but neither feeding nor oviposition site preference was affected by willow genotype. Adult feeding and oviposition preferences were not correlated with larval performance. [source] Size-dependent reproductive dominance in foundresses of Ropalidia plebeiana, an Australian paper wasp forming nest aggregations (Hymenoptera: Vespidae)ENTOMOLOGICAL SCIENCE, Issue 4 2003Hirokazu FUKUDA Abstract The relationship between reproductive status and body size in foundresses of Ropalidia plebeiana, an Australian endemic paper wasp forming huge aggregations of nests, was examined. Foundresses with developed ovaries (laying foundresses) in multifoundress colonies tended to be larger than foundresses in single-foundress colonies and foundresses with undeveloped ovaries (non-laying foundresses). However, the laying foundress was not always the largest of the foundresses in a colony. Body shape in foundresses varied according to simple allometric growth, while foundresses and first brood females diverged in their growth parameters in the preimaginal stage. [source] Electronic Structure and Geminate Pair Energetics at Organic,Organic Interfaces: The Case of Pentacene/C60 HeterojunctionsADVANCED FUNCTIONAL MATERIALS, Issue 23 2009Stijn Verlaak Abstract Organic semiconductors are characterized by localized states whose energies are predominantly determined by electrostatic interactions with their immediate molecular environment. As a result, the details of the energy landscape at heterojunctions between different organic semiconductors cannot simply be deduced from those of the individual semiconductors, and they have so far remained largely unexplored. Here, microelectrostatic computations are performed to clarify the nature of the electronic structure and geminate pair energetics at the pentacene/C60 interface, as archetype for an interface between a donor molecule and a fullerene electron acceptor. The size and orientation of the molecular quadrupole moments, determined by material choice, crystal orientation, and thermodynamic growth parameters of the semiconductors, dominate the interface energetics. Not only do quadrupoles produce direct electrostatic interactions with charge carriers, but, in addition, the discontinuity of the quadrupole field at the interface induces permanent interface dipoles. That discontinuity is particularly striking for an interface with C60 molecules, which by virtue of their symmetry possess no quadrupole. Consequently, at a pentacene/C60 interface, both the vacuum-level shift and geminate pair dissociation critically depend on the orientation of the pentacene ,-system relative to the adjacent C60. [source] Growth of the tufted-tailed ratINTEGRATIVE ZOOLOGY (ELECTRONIC), Issue 4 2007Vololomboahangy R. RANDRIANJAFY Abstract Eliurus myoxinus (Rodentia: Nesomyidae, Nesomyinae) is one of the four species of endemic Malagasy rodents known to exist in the Ankarafantsika National Park, northwestern Madagascar. In order to study growth parameters and to determine at which age E. myoxinus commences breeding, we used two different techniques: captive breeding and a capture-mark-release field program in the species' natural habitat. The data collected on the breeding of E. myoxinus in captivity demonstrated that females can give birth to a litter of up to four pups, with up to four litters per calendar year. Reproduction of E. myoxinus was more likely to be continuous in captivity than under natural habitat conditions. If parturition failed, then post-partum mating occurred. Pups had a rapid linear growth phase from birth until 1 month of age. Between 1.5 and 2 months of age, the growth rate continued to increase, but then decreased at around the time of weaning, which occurred by 3.5 months of age. The successive maximum method of age determination showed that individuals at the "young" stage had an average body length of 90 mm and a weight of 30 g and were between 1.5 and 2 months old. The greatest variation in measurements of juveniles occurred at the age of 3.5 months. At this stage, sub-adults resembled adults but their external genitalia were not well developed. Individuals were classified as adults if they had reached a body length of 110 mm and a body weight of 40 g. This occurred at more than 4.5 months of age when the animals were generally reproductively active. The Vo n Bertalanffy method indicated that individuals reach the adult stage by 6 to 7 months. Males grew more rapidly than females, reaching adulthood by 5.5 months of age, whereas females only reached adulthood several weeks later. This species is polygamous. The sex ratio of pups at birth favored females by approximately 3:1. The higher proportion of female pups at birth may represent a survival strategy of this species, possibly associated with ecological conditions. [source] Effect of physico-chemical and molecular mobility parameters on Staphylococcus aureus growthINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 8 2003Elena Vittadini Summary The role played by water activity, ,mobility' and physico-chemical properties of the media in modulating microbial response has been the object of large debate in the scientific community. In this study, Staphylococcus aureus growth parameters (lag phase and cell density at 24 h) in brain heart infusion (BHI) and BHI:NaCl (1:1) were analysed in their correlation with physico-chemical/mobility parameters descriptive of the media [solid content, aw, kinematic viscosity, 17O NMR (R2, Pbw and )]. In these high moisture content, liquid and ,homogeneous' media S.aureus growth related to all the physico-chemical and molecular mobility parameters analysed in a similar manner and it was found to be influenced more significantly by added NaCl than by the physico-chemical and molecular mobility of the media. Staphylococcus aureus growth parameters correlated better with aw (relatively independent of NaCl concentration) than with any other parameter considered in this study. [source] Anisotropic Shape Control of Colloidal Inorganic Nanocrystals,ADVANCED MATERIALS, Issue 5 2003S.-M. Lee Abstract The systematic shape control of colloidal nanocrystals including one-dimensional (1D) nanorods remains a key issue in the "bottom,up" approach of nanoscience. Here, we examine the anisotropic structural evolution of various semiconductor nanocrystals and systematically elucidate the key growth parameters for their shape control. The crystalline phase of nucleating seeds and kinetic growth regimes controlled by changing growth parameters are crucial for the determination of the 1D nanocrystal geometry. [source] Age, growth and sexual development of solenette, Buglossidium luteum (Risso, 1810), in the central Aegean SeaJOURNAL OF APPLIED ICHTHYOLOGY, Issue 3 2010A. T., lkyaz Summary Age, growth, spawning period and maturity of the solenette (Buglossidium luteum Risso, 1810) were studied in the central Aegean Sea to provide fisheries managers with essential data for science-based management. A total of 1220 samples were collected by trawl hauls from July 2004 to June 2007 in ,zmir Bay (Turkey). Sample sizes ranging from 5.3 to 11.6 cm total length were composed of 46% females, 32% males and 22% immature individuals, with a female to male ratio of 1 : 0.7. Age composition stages of the females were from I to IV, and males between I and III. The length,weight relationship was calculated as W = 0.0101L3.008 for all samples. Estimated von Bertalanffy growth parameters were L = 13.30 cm, to = ,0.440 year and k = 0.481 year,1, with a growth performance index of 1.93 (,'). The spawning period began in April and continued until July. Lengths at first maturity of females and males were 8.1 and 7.9 cm total length, respectively. Both sexes matured at the age of 2 years. [source] Age and growth of the Randall's threadfin bream Nemipterus randalli (Russell, 1986), a recent Lessepsian migrant in Iskenderun Bay, northeastern MediterraneanJOURNAL OF APPLIED ICHTHYOLOGY, Issue 3 2010D. Erguden Summary Randall's threadfin bream, Nemipterus randalli, first recorded in Iskenderun Bay in Turkey in 2008, seems to have increased in the region. The species, widespread in the western Indian Ocean and with a rapid expansion, appears to have migrated to the bay via the Red Sea. Although its presence in the region has been published, there has been little or no information as to age and growth parameters of this Lessepsian migrant in its new habitat. The present study aims to determine the basic age and growth parameters of the species colonized in the region. A total of 379 collected individuals were studied from November 2007 to October 2008. Total specimen lengths ranged from 4.80 to 21.50 cm, and weights from 1.10 to 138.36 g. Maximum age was 3 years for both sexes. The length,weight relationship was described as W = 0.0011 × L3.061 (r2 = 0.982). The von Bertalanffy growth parameters were: L, = 34.96 cm; K = 0.214 year,1; t0 = ,1.244 year for the entire population. These data were compared with results from studies made in other geographic areas. [source] Preliminary estimates of the population parameters of major fish species in Lake Ayamé I (Bia basin; Côte d'Ivoire)JOURNAL OF APPLIED ICHTHYOLOGY, Issue 1 2010L. Tah Summary Length frequency data collected from artisanal fisheries in Lake Ayamé I (Côte d'Ivoire) from August 2004 to 2005 were analysed with Fisat software using the Elefan package to estimate the population parameters of 11 fish species. Asymptotic values for total length (L,) ranged from 20.5 cm for Brycinus imberi to 78 cm for Mormyrops anguilloides. Growth rates (k) varied from 0.24 year,1 for Chrysichthys nigrodigitatus to 0.57 year,1 for Hemichromis fasciatus. The growth performance estimates were close to the values found by others authors and reported in FishBase 2008. Fishing mortality (F) and exploitation rate (E) were found to be below optimum levels of exploitation for most fish species. Recruitment was noted as year,round and bimodal for most studied populations. The data sets were limited in most cases, thus this study provides preliminary population parameters only, but for species for which information is scarce. For application in stock assessment, the growth parameters and especially the natural mortality data require further confirmation. [source] Influence of dietary amino acid profiles on growth performance and body composition of juvenile grouper Epinephelus coioidesJOURNAL OF APPLIED ICHTHYOLOGY, Issue 2 2008Z. Luo Summary A feeding experiment was conducted to investigate the effects of dietary amino acid (AA) profiles on growth performance and body composition of juvenile grouper Epinephelus coioides (initial mean weight: 68.1 ± 1.0 g, mean ± SD). Five diets contained 30% fishmeal, 12% soy protein concentrate and 20% crystalline amino acids (CAAs); the control diet contained 54% fishmeal and 17% soy protein concentrate as intact protein sources. CAAs were added to the five diets to simulate the AA pattern found in white fishmeal protein (WFP), brown fishmeal protein (BFP), hen egg protein (HEP), grouper E. coioides juvenile protein (GJP) and red sea bream egg protein (REP), respectively. The highest WG and SGR were obtained in fish fed the control diet, followed by fish fed the diets with AA profiles of WFP and GJP. Fish fed the diets with AA profiles of BFP, REP and HEP showed relatively poor growth performance. Feed utilization showed a similar trend in growth parameters. Protein content of whole body among these treatments showed no significant differences (P > 0.05), but lipid content of whole body showed the highest value in the control group (P < 0.05). Dietary AA profiles significantly influenced plasma protein, cholesterol, triacylglycerol and glucose concentrations (P < 0.05). Dietary AA profiles significantly influenced the condition factor, hepatosomatic index and intraperitoneal fat ratio (P < 0.05). [source] Population biology and status of exploitation of introduced garfish Belone belone euxini (Günther, 1866) in the Black SeaJOURNAL OF APPLIED ICHTHYOLOGY, Issue 5 2006O. Samsun Summary The garfish Belone belone euxini (Günther, 1866) is a commercially important pelagic fish species in Sinop artisanal fishery, which is showing a decreasing trend in catch results. As a basis for fisheries management a sampling program was carried out between October 2000 and September 2001 along the Turkish coast of the Black Sea, to study the population structure, growth, and reproduction cycle of garfish in the area, and to achieve a rough estimate of exploitation. The length,weight relationship and von Bertalanffy growth parameters were estimated as W = 0.00076 L3.137, L, = 74.64 cm, K = 0.13 year,1, to = ,3.67, respectively. First sexual maturity was estimated at age 2 and at a total length of 38.8 cm for females. The spawning period was from May to September. The total fecundity,length relationship was estimated as F = 0.0041 L4.1086 (r2 = 0.92). Mortality rates were Z = 1.24 year,1, M = 0.23 year,1and F = 1.01 year,1 for total, natural, and fishing mortality, respectively. The exploitation ratio E = 0.81 indicates that the population is heavily exploited. [source] Some biological characteristics of the garfish (Belone belone L., 1761) in Izmir Bay, Aegean SeaJOURNAL OF APPLIED ICHTHYOLOGY, Issue 5 2004D. Uçkun Summary The present work was aimed at determining the growth parameters of the garfish, Belone belone, a commercially important pelagic fish species in Izmir Bay (Aegean Sea). A total of 347 garfish specimens was collected during the period January,December 1997 from purse-seine boats operating in Izmir Bay. Fork length and total weight of the specimens ranged from 26.0 to 54.5 cm and from 16.51 to 281.73 g, respectively. Maximum age group determined was V for females and IV for males. Female : male ratio was 1 : 0.45. Most specimens belonged to age group II. The von Bertalanffy growth equations for length and weight were for both sexes. [source] Mutual influence of protein and lipid feed content on European catfish (Silurus glanis) growthJOURNAL OF APPLIED ICHTHYOLOGY, Issue 2 2004E. Has-Schön Summary We wished to determine protein and lipid content in pelleted raw fish food, necessary for optimal growth of European catfish (Silurus glanis). Experiments were set up in 20 cages, each holding 30 young catfish. Fishes in each cage received a different food combination over a 98-day period at favourable physical and chemical water conditions. Food protein content varied between 37.5 and 45%, while lipid content, added in the form of soybean oil, varied between 3 and 11%. The oil contained an adequate , -fatty acids concentration, necessary for fish growth. The main growth indicators determined at the end of experiment were total body gain, specific growth rate and feed conversion ratio. There was a high statistical difference among the experimental groups receiving variable food combinations for each growth parameter (P < 0.001). Both protein and lipid food content affected growth parameters, but in a different manner. Further analysis , percentage of change depending on lipid to protein ratio and bivariate surface analysis , allowed us to recognize the most economical combination: 39.5% protein + 9% lipid content. The addition of 9% soybean oil to the fish food reduces the necessary protein concentration by 5.5%, with resulting identical catfish growth effects. [source] The potential use of scales for estimating age and growth of Mediterranean albacore (Thunnus alalunga)JOURNAL OF APPLIED ICHTHYOLOGY, Issue 4 2003P. Megalofonou Summary The ability to accurately estimate the age of fishes is critical for conducting stock assessments and developing fishery management policies. Scales were collected from albacore, Thunnus alalunga, caught in the Mediterranean Sea during the years 1989,1995 to estimate their age and growth. Ages, which ranged from 1+ to 6+ years, were estimated from the interpretation of the concentric rings on the scales of 473 individuals that ranged in fork length from 55.5 to 89 cm. Males reached a greater size and age than females. The relatively close agreement in the mean lengths at ages estimated by scales and other techniques constituted a preliminary verification of the method. The von Bertalanffy growth model was fitted to mean lengths at estimated ages, resulting in the following growth parameters for the combined sexes: L, = 86 cm, K = 0.4, to = ,0.8 years. Parameter estimates were in agreement with what is known about life history of the species in the Mediterranean. Moreover, the growth rates were consistent with length increment observations from five tag returns, which lend support to our working hypothesis that the scale-rings are annual structures. When the Mediterranean albacore growth parameters were compared with those of Atlantic Ocean albacore using scale age estimates, there were significant differences between the two populations, and Mediterranean albacore remain significantly smaller than Atlantic Ocean albacore. [source] Control of Aspergillus section Flavi growth and aflatoxin accumulation by plant essential oilsJOURNAL OF APPLIED MICROBIOLOGY, Issue 1 2008R. Bluma Abstract Aims:, The antifungal effect of Pimpinella anisum (anise), Pëumus boldus (boldus), Mentha piperita (peppermint), Origanum vulgare (oregano) and Minthosthachys verticillata (peperina) essential oils against Aspergillus section Flavi (two isolates of Aspergillus parasiticus and two isolates of Aspergillus flavus) was evaluated in maize meal extract agar at 0·982 and 0·955 water activities, at 25°C. Methods and Results:, The percentage of germination, germ-tube elongation rate, growth rate and aflatoxin B1 (AFB1) accumulation at different essential oils concentrations were evaluated. Anise and boldus essential oils were the most inhibitory at 500 mg kg,1 to all growth parameters of the fungus. These essential oils inhibited the percentage of germination, germ-tube elongation rate and fungal growth. AFB1 accumulation was completely inhibited by anise, boldus and oregano essential oils. Peperina and peppermint essential oils inhibited AFB1 production by 85,90% in all concentrations assayed. Conclusions:, Anise and boldus essential oils could be considered as effective fungitoxicans for Aspergillus section flavi. Significance and Impact of the Study:, Our results suggest that these phytochemical compounds could be used alone or in conjunction with other substances to control the presence of aflatoxigenic fungi in stored maize. [source] | ||||||||||||||||||||||||||||