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Growth Measurements (growth + measurement)
Selected AbstractsAmmonium perchlorate effects on thyroid function and growth in bobwhite quail chicksENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 4 2004F. M. ANNE Mcnabb Abstract Bobwhite quail chicks were used to investigate ammonium perchlorate (AP; NH4ClO4) effects on thyroid function and growth. Beginning at 3 to 4 d posthatch, we evaluated organismal thyroid status (circulating hormones), activation of the hypo-thalamic-pituitary-thyroid axis (thyroid wt) and thyroidal hormone content over a wide range of AP concentrations (50 ,g/L , 4,000 mg/L) in drinking water, for relatively short (2-week) and longer (8-week) exposures. Thyroidal thyroxine (T4) content, the most sensitive index of decreased thyroid function, decreased markedly in response to increasing perchlorate exposure. Thyroid weight and plasma T4 were less sensitive indicators and similar in their ability to detect thyroid changes. Growth measurements (body wt and skeletal growth) were very insensitive indices. Because thyroids contain large hormone stores, with low exposures or short time periods, these stores can be used to maintain circulating hormones, at least temporarily. Most depletion of thyroidal T4 occurred during the first two weeks of AP exposure. Subsequent decreases were at a slower rate presumably because thyrotropin stimulation of the thyroids at least partially compensated for some of the perchlorate effect. Additional studies of the interactions between AP concentration and exposure time are needed for understanding the complex nature of thyroid responses to perchlorate. [source] Fetal Alcohol Spectrum Disorders in Children Residing in Russian Orphanages: A Phenotypic SurveyALCOHOLISM, Issue 3 2006Laurie C. Miller Background: Alcohol use in Russia is among the highest in the world. Over 600,000 children reside in institutional care in Russia, most of them in baby homes and orphanages. The actual prevalence of fetal alcohol spectrum disorders (FASD) among these children is unknown. Therefore, we performed a systematic survey of phenotypic features associated with prenatal alcohol exposure among institutionalized Russian children and related these findings to their growth, development, medical, and social histories. Methods: Phenotypic screening was conducted of all 234 baby home residents in the Murmansk region of Russia (mean age 21+12.6 months). Phenotypic expression scores were devised based on facial dysmorphology and other readily observable physical findings. Growth measurements from birth, time of placement in the baby home, and at present were analyzed. In addition, the charts of 64% of the children were randomly selected for retrospective review. Information collected included maternal, medical, developmental, and social histories. Results: Thirteen percent of children had facial phenotype scores highly compatible with prenatal alcohol exposure and 45% had intermediate facial phenotype scores. These scores correlated with maternal gravidity and age. At least 40% of mothers in whom history was available ingested alcohol during pregnancy; some also used illicit drugs and tobacco. Z scores for growth measurements corresponded to phenotypic score, as did the degree of developmental delay. Children with no or mild delay had significantly lower phenotypic scores than those with moderate or severe delay (p=0.04); more than 70% of children with high phenotypic scores were moderately or severely delayed. Conclusions: More than half of residents of the baby homes in Murmansk, Russia, have intermediate (45%) or high (13%) phenotypic expression scores suggesting prenatal exposure to alcohol. Despite good physical care, stable daily routine, availability of well-trained specialists, and access to medical care, these vulnerable children show significant growth and developmental delays compared with their institutionalized peers. [source] A BATCH CULTURE METHOD FOR MICROALGAE AND CYANOBACTERIA WITH CO2 SUPPLY THROUGH POLYETHYLENE MEMBRANES,JOURNAL OF PHYCOLOGY, Issue 4 2010Yvonne Pörs A new method for CO2 supply to photoautotrophic organisms was developed, and its applicability for measuring specific growth rates in shaken batch cultures of cyanobacteria and unicellular algae was shown. Small bags containing a concentrated carbonate buffer with a CO2 partial pressure of 32 mbar were prepared from a thin foil of low density polyethylene (LDPE). These bags were inserted as CO2 reservoirs (CRs) into polystyrene culture flasks with gas-permeable screw caps, which were suitable to photometric growth measurement. CO2 was released directly into the medium with membrane-controlled kinetics. The CRs were not depleted within 1 week, although the atmosphere in the culture vessel exchanged rapidly with the ambient air. Rates of initial growth and final densities of the cultures of six different unicellular algal species and one cyanobacterium were markedly increased by diffusive CO2 supply from the CR. In the presence of a CR, growth was exponential during the first 2 d in all cultures studied. The method described allowed a high number of measurements of specific growth rates with relatively simple experimental setup. [source] Family migration and physical growth in Merida, Yucatan, MexicoAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 3 2009Hugo Azcorra Merida city in Yucatan, Mexico, has received rural-to-urban migration for decades, with most immigrants settling in the city's southern neighborhoods. Exposure of immigrants to new environmental and sociocultural conditions can generate biological responses, including changes in physical growth pattern at early age. We performed a study to identify and measure the effects of family migration into south Merida on growth in 4- to 6-year-old children, measuring weight, height, sitting height, and calculated arm muscle and fat areas of 445 children: 228 natives (116 females) and 217 immigrants (118 females) and collecting family social and demographic data. Statistical analysis focused on determining differences in growth, socioeconomic, and biological variables by migratory condition and generating multiple regression models for each growth measurement. No univariate statistical differences (P > 0.05, Student's t- test) were observed in growth between studied children. Multiple regression analyses showed age, sex, mother's height, birth order, birth weight, family income, zone of residence, diet, and febrile episodes had an effect on growth. Neither the migration variable used above nor any other definition of migrant had a significant effect on growth. The lack of differences in growth between immigrant and native children is probably due to similarity in socioeconomic conditions of their families. Am. J. Hum. Biol., 2009. © 2009 Wiley-Liss, Inc. [source] Resolving the differences in plant burial responsesAUSTRAL ECOLOGY, Issue 1 2010MATTHEW E. GILBERT Abstract Burial is one of the major factors influencing plant ecology in deserts and coastal areas. Consequently, many studies have measured the responses of dune plants to sand burial. However, there remains little agreement about the mechanisms and characteristics constituting the burial response of plants. In particular, stimulation of growth has been reported as the most common plant burial response; however, stimulation has not been reported consistently among studies. Here, a literature survey showed that the depth of burial relative to the height of the plant determined whether the growth of a species was stimulated by burial. Growth stimulation was limited to shallow burial depths, while burial depths greater than the height of the plant consistently resulted in reduced growth. As studies used widely differing burial depths or units of growth measurement, the variation in reported stimulation of plant growth can be partly attributed to differences in experimental procedure. The stimulation of growth in many species was accompanied by an increase in photosynthesis over a limited period and by a shift in biomass allocation from root to shoot. Most plants demonstrated stimulated growth (up to 200%) in response to shallow burial indicating that some burial response mechanisms are general to many species. However, a few specialist dune species displayed a much greater ability to respond to burial (up to 700% stimulation of plant mass). Although allocation shifts and increased photosynthesis have been shown to be associated with dune plant burial response, there remains a need for field measurements that focus on the diversity of mechanisms underlying plant response to burial. [source] Variable amplitude loading in the very high-cycle fatigue regimeFATIGUE & FRACTURE OF ENGINEERING MATERIALS AND STRUCTURES, Issue 8-9 2002S. E. STANZL-TSCHEGG ABSTRACT Ultrasonic fatigue testing is appropriate to perform random loading tests in the regime of very high numbers of cycles. It has been shown that neither an endurance limit nor a threshold stress intensity exists under loading with randomly varying amplitudes even for materials that do show these limits under constant amplitude loading conditions. The technical features of the ultrasonic testing technique in order to perform random fatigue tests are shortly described. Endurance tests were performed on smooth specimens of AlSi7Mg (A356.0) aluminium alloy and on notched AISI 4142 and C45 steel specimens. The previous studies of crack propagation and threshold behaviour on AISI 420 ferritic chromium steel and GGG 100-B cast iron are included. Experimental results on lifetime and fatigue crack growth measurements under randomly varying amplitudes, as well as lifetime predictions, based on constant amplitude measurements and damage accumulation calculations are reported. [source] Linking marine and freshwater growth in western Alaska Chinook salmon Oncorhynchus tshawytschaJOURNAL OF FISH BIOLOGY, Issue 6 2009G. T. Ruggerone The hypothesis that growth in Pacific salmon Oncorhynchus spp. is dependent on previous growth was tested using annual scale growth measurements of wild Chinook salmon Oncorhynchus tshawytscha returning to the Yukon and Kuskokwim Rivers, Alaska, from 1964 to 2004. First-year marine growth in individual O. tshawytscha was significantly correlated with growth in fresh water. Furthermore, growth during each of 3 or 4 years at sea was related to growth during the previous year. The magnitude of the growth response to the previous year's growth was greater when mean year-class growth during the previous year was relatively low. Length (eye to tail fork, LETF) of adult O. tshawytscha was correlated with cumulative scale growth after the first year at sea. Adult LETF was also weakly correlated with scale growth that occurred during freshwater residence 4 to 5 years earlier, indicating the importance of growth in fresh water. Positive growth response to previous growth in O. tshawytscha was probably related to piscivorous diet and foraging benefits of large body size. Faster growth among O. tshawytscha year classes that initially grew slowly may reflect high mortality in slow growing fish and subsequent compensatory growth in survivors. Oncorhynchus tshawytscha in this study exhibited complex growth patterns showing a positive relationship with previous growth and a possible compensatory response to environmental factors affecting growth of the age class. [source] Fetal Alcohol Spectrum Disorders in Children Residing in Russian Orphanages: A Phenotypic SurveyALCOHOLISM, Issue 3 2006Laurie C. Miller Background: Alcohol use in Russia is among the highest in the world. Over 600,000 children reside in institutional care in Russia, most of them in baby homes and orphanages. The actual prevalence of fetal alcohol spectrum disorders (FASD) among these children is unknown. Therefore, we performed a systematic survey of phenotypic features associated with prenatal alcohol exposure among institutionalized Russian children and related these findings to their growth, development, medical, and social histories. Methods: Phenotypic screening was conducted of all 234 baby home residents in the Murmansk region of Russia (mean age 21+12.6 months). Phenotypic expression scores were devised based on facial dysmorphology and other readily observable physical findings. Growth measurements from birth, time of placement in the baby home, and at present were analyzed. In addition, the charts of 64% of the children were randomly selected for retrospective review. Information collected included maternal, medical, developmental, and social histories. Results: Thirteen percent of children had facial phenotype scores highly compatible with prenatal alcohol exposure and 45% had intermediate facial phenotype scores. These scores correlated with maternal gravidity and age. At least 40% of mothers in whom history was available ingested alcohol during pregnancy; some also used illicit drugs and tobacco. Z scores for growth measurements corresponded to phenotypic score, as did the degree of developmental delay. Children with no or mild delay had significantly lower phenotypic scores than those with moderate or severe delay (p=0.04); more than 70% of children with high phenotypic scores were moderately or severely delayed. Conclusions: More than half of residents of the baby homes in Murmansk, Russia, have intermediate (45%) or high (13%) phenotypic expression scores suggesting prenatal exposure to alcohol. Despite good physical care, stable daily routine, availability of well-trained specialists, and access to medical care, these vulnerable children show significant growth and developmental delays compared with their institutionalized peers. [source] Induction of systemic protection against rust infection in broad bean by saccharin: effects on plant growth and developmentNEW PHYTOLOGIST, Issue 2 2005Celia Boyle Summary ,,Here, we examine the effect of saccharin on the induction of systemic resistance in broad bean (Vicia faba) to the rust fungus Uromyces viciae-fabae. ,,Saccharin was applied to beans at the three-leaf stage, either as a soil drench or by painting the solution on to first leaves. Plants were then challenge inoculated with the rust 1, 6, 10 and 14 d following saccharin treatment, after which they were harvested, assessed for the intensity of rust infection and plant growth measurements conducted. ,,Foliar application of saccharin did not induce systemic protection to rust infection until 14 d after application and was less effective than saccharin applied as a soil drench. When saccharin was applied as a drench, systemic protection was not observed until 6 d after application, but was still apparent in plants 14 d after application of the drench. ,,Irrespective of the method of application, saccharin had no significant effect on fresh and dry weights or leaf area of the plants. Saccharin applied as a drench did, however, reduce the number of leaflets produced. [source] Safety and efficacy of a new extensively hydrolyzed formula for infants with cow's milk protein allergyPEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 4 2008B. Niggemann Cow's milk protein allergy (CMPA) is best treated by complete elimination of cow's milk from the diet. For infants with CMPA who cannot be breast-fed, formulas based on extensively hydrolyzed proteins or on amino acids are the preferred substitutes for cow's milk-based formulas. In this study, we compared the tolerance and growth of infants with CMPA who were fed a new extensively hydrolyzed formula containing lactose (eHF) with those who were fed an amino acid formula (AAF). This was a prospective, multi-center, randomized, reference-controlled study. Seventy-seven infants <12 months old with suspected CMPA were enrolled. In 66 of these, CMPA was confirmed by oral challenge in a double-blind, placebo-controlled food challenge (DBPCFC) or by a medical history of severe allergic reaction to cow's milk and a positive skin prick test. These infants were then tested for their reaction to eHF and AAF in a DBPCFC. All infants tolerated both formulas and were randomized to receive either eHF (n = 34) or AAF (n = 32) for 180 days. Growth (weight, length, and head circumference) and tolerance [skin, gastro-intestinal, and respiratory tract symptoms of allergy] were evaluated after 30, 60, 90, and 180 days. There were no significant differences between the two groups in any of the growth measurements. Length and head circumference were similar to Euro-growth standards, but weight was slightly lower. Gastro-intestinal and respiratory tract symptoms of allergy were also similar in the two groups. However, whereas SCORAD scores for atopic dermatitis remained constant throughout the study in infants-fed eHF, there was a slight decrease in those fed AAF. Infants-fed eHF had significantly fewer incidents of vomiting than infants-fed AAF and a significantly higher frequency of soft stools. The new eHF is safe and well tolerated in infants diagnosed with CMPA. [source] | |||||||||||||