Environmental factors affecting growth of eastern sand darter (Ammocrypta pellucida)

2008 ◽  
Vol 86 (7) ◽  
pp. 714-722 ◽  
Author(s):  
D. A.R. Drake ◽  
M. Power ◽  
M. A. Koops ◽  
S. E. Doka ◽  
N. E. Mandrak
Keyword(s):  
Environmental Factors ◽  
Growth Rates ◽  
First Year ◽  
High Discharge ◽  
Factors Affecting ◽  
Growth Variability ◽  
Substrate Composition ◽  
Structured Population ◽  
Northern Edge ◽  
First Year Of Life

Environmental factors affecting growth of the threatened eastern sand darter ( Ammocrypta pellucida (Putnam, 1863)) were examined using specimens sampled from the northern edge of its range to determine the species’ critical habitat. Length-at-age increments were determined from scale samples as surrogates for growth rates based on back-calculated lengths using the Fraser–Lee method. During the first year of life, 82% of total length is attained, suggesting considerable energetic partitioning towards reproduction following age-0. Positive relationships between age-0 length increments and sand substrates and between age-0 length increments and mean annual channel discharge indicated greatest first-year growth within sand-dominated, high-discharge habitats. Environmental factors that occurred at coarse spatial and temporal levels (i.e., mean annual channel discharge) explained more of the growth variability among eastern sand darters than those occurring at fine levels (i.e., site-level substrate composition). This study indicates that environmental factors can be used to explain variability in cohort-structured population and site-level growth of eastern sand darters.

GROWTH AND DEVELOPMENT OF NEGRO INFANTS

PEDIATRICS ◽  
1955 ◽  
Vol 16 (1) ◽  
pp. 24-30
Author(s):  
Roland B. Scott ◽  
Angella D. Ferguson ◽  
Melvin E. Jenkins ◽  
Fred F. Cutter
Keyword(s):  
Environmental Factors ◽  
Private Practice ◽  
Growth And Development ◽  
First Year ◽  
Daily Care ◽  
Patterns Of Behavior ◽  
First Year Of Life

The time of occurrence of 12 neuromuscular patterns of behavior in the development of 2 groups of Negro infants from different socio-economic levels during the first year of life is presented. The Negro infants from the clinic showed acceleration over the Negro infants from private practice in their development from the 8th to the 35th week of life, after which time, the development of the 2 groups was essentially the same. The Negro infants as a group showed acceleration in their development when compared with a group of white infants studied in a similar manner by Aldrich except in 2 patterns, "smiling" and "vocalization." A marked similarity was noted during the first 30 weeks of life in the development of the white and Negro infants from private practice whose socio-economic backgrounds were substantially similar. The differences and similarities observed in the neuromuscular behavior in the 3 groups studied may be attributed mainly to environmental factors. The observed acceleration in the Negro infants is apparently an expression of greater permissiveness in daily care as practiced by the mothers or mother substitutes in the lower socio-economic classes.

Age, stucture, growth rates and movements of sea mullet, Mugil cephalus L., and Yellow-eye Mullet, Aldrichetta forsteri (Valenciennes), in the Swan-Avon river system, Western Australia

1981 ◽  
Vol 32 (4) ◽  
pp. 605 ◽  
Author(s):  
CF Chubb ◽  
IC Potter ◽  
CJ Grant ◽  
RCJ Lenanton ◽  
J Wallace
Keyword(s):  
Growth Rates ◽  
River System ◽  
First Year ◽  
Length Frequency ◽  
Frequency Distributions ◽  
Using Data ◽  
The Times ◽  
First Year Of Life ◽  
Breeding Seasons ◽  
System 1

The age structure, growth rates and movements of M. cephalus and A forsteri in the Swan-Avon river system have been investigated using data obtained from beach seining and gill netting carried out between February 1977 and June 1980. Length-frequency data and scale readings show that the populations of both species consist predominantly of 0+ and 1 + fish. From the times when the smallest fry (20-30 mm) were present in the lower part of the river system, and from the condition of the gonads of older fish, the breeding seasons of the sea and yellow-eye mullets have been estimated as extending from March to September and from March to August respectively. The bimodality or polymodality exhibited by the length-frequency distributions for the 0 + year classes suggest that in both species groups of individuals spawn at slightly different times. The range of mean total lengths and weights of animals caught in May near the end of the first year of life was 178-222 mm and 64-119 gin M. cephalus and 136-154 mm and 19-30 g in A. forsteri, which shows that the growth of each of these two species of mullet is relatively very rapid in the Swan-Avon river system. 1 + and 2 + fish tend to leave the estuary for varying periods. Although 0+ fish of both species utilized the shallow banks of the estuary throughout the year. the sea mullet moved further upstream and were not as consistently abundant in the lower estuary. Since 0+ yellow-eye mullet 40-100 mm long were also abundant in marine coastal waters between January and May. and sea mullet of comparable age were rarely observed in these regions, it would appear that M. cephalus is the more estuarine-dependent of the two species. Commercial catches of M. cephalus were greater than those of A. forsteri. This feature can be related in part to the much faster growth rate of M. cephalus, which results in a larger proportion of its youngest year classes reaching the minimum legal size for capture prior to the time when they leave the estuary in large numbers.

scholarly journals Composition and Associations of the Infant Gut Fungal Microbiota with Environmental Factors and Childhood Allergic Outcomes

mBio ◽  
2021 ◽  
Author(s):  
Rozlyn C. T. Boutin ◽  
Hind Sbihi ◽  
Ryan J. McLaughlin ◽  
Aria S. Hahn ◽  
Kishori M. Konwar ◽  
...  
Keyword(s):  
Environmental Factors ◽  
Early Life ◽  
Geographical Location ◽  
Fungal Communities ◽  
First Year ◽  
Season Of Birth ◽  
Early Life Factors ◽  
Fungal Microbiota ◽  
First Year Of Life ◽  
First Time

Recent evidence suggests an immunomodulatory role for commensal fungi (mycobiota) in the gut, yet little is known about the composition and dynamics of early-life gut fungal communities. In this work, we show for the first time that the composition of the gut mycobiota of Canadian infants changes dramatically over the course of the first year of life, is associated with environmental factors such as geographical location, diet, and season of birth, and can be used in conjunction with knowledge of a small number of key early-life factors to predict inhalant atopy status at age 5 years.

scholarly journals The Impact of Learning Environment on EFL Students’ Academic Achievement: A study of Socio-Cultural Factors Affecting Academic Achievement

2022 ◽  
Author(s):  
Elmakki AMIRI ◽  
Abderrahim El KARFA
Keyword(s):  
Academic Achievement ◽  
Environmental Factors ◽  
Learning Environment ◽  
Foreign Language ◽  
First Year ◽  
First Year Students ◽  
Factors Affecting ◽  
Academic Achievements ◽  
Efl Students ◽  
The Impact

It is worth pointing out that learning a foreign language in a multicultural context is a long and complex undertaking. Several factors influence whether or not English as a Foreign Language (EFL) students can accurately perceive and produce the foreign language. These variables can potentially contribute to the success and, or failure in learning and acquiring a foreign language. Given the Moroccan educational system, the research provided minimal insight into the relationship between those factors and language achievement. The present study’s aim, therefore, was to investigate the environmental factors that affect students’ academic performance. It also aimed to find out how these variables affect students’ academic achievements. To achieve this aim, data have been collected via open-ended questionnaires, and interviews addressed mainly to First Year Students of Master Programs, Department of English, FLDM, USMBA-Fez. The findings have shown that students’ academic achievements were significantly positively/negatively linked with the environmental factors, namely societal, home/family and school/classroom variables. The findings also revealed that the more highly sophisticated the social environment is, the more likely it is to foster EFL students’ academic achievements. In addition, the more similarity exists between the students’ cultures, the more successful the learning is. This study also showed that the development of EFL proficiency is a product of contextual factors influence. As such, the study concludes with several implications that brought up for possible effective change in the future to enhance the learning environment atmosphere, boost students’ academic achievements, and, therefore, achieve better results.

THE INFLUENCE OF REPRODUCTION ON BODY WEIGHT IN WOMEN

1957 ◽  
Vol 15 (4) ◽  
pp. 393-409 ◽  
Author(s):  
THOMAS McKEOWN ◽  
R. G. RECORD
Keyword(s):  
Body Weight ◽  
Early Pregnancy ◽  
Growth Rates ◽  
First Year ◽  
Weight Changes ◽  
Present Communication ◽  
Small Loss ◽  
One Year ◽  
First Year Of Life

SUMMARY 1. Data recorded in respect of all women whose children were born in a county borough during one year included the weight at the first antenatal examination (adjusted according to the number of days by which it preceded or followed the 124th day of gestation), and at 3, 6, 9, 12 and 24 months after delivery. The present communication is concerned with the influence of reproduction on body weight. 2. It is estimated that between conception and 24 months after birth women gained, on the average, approximately 6·6 lb. This is about 5 lb. more than would have been added in the same period if they had not been pregnant. Reasons are given for believing that these estimates may be a little low, probably not by more than 1 lb. 3. The increase in weight occurred mainly during pregnancy. From 3 months after delivery changes in mean weight were relatively small: a loss of 1·8 lb. between 3 and 12 months, and a gain of 0·6 lb. between 12 and 24 months. 4. The increment in mean weight between conception and 24 months increased slightly with parity, and, less certainly, with age. The most striking association with these variables occurred between 3 and 12 months after birth, when the proportion of women who gained weight decreased with increasing parity and increased with increasing age (Fig. 5). It is suggested that this relationship is probably attributable to an association between age and parity and social circumstances, and it is shown that the same trend was exhibited by the growth rates of the offspring of the same mothers during the first year of life (Fig. 6). 5. Lactation had little influence on mean weight. It resulted in a small loss during the period of lactation, but its effect was almost eliminated at 24 months after delivery (Fig. 7). 6. During the various intervals between early pregnancy and 24 months after delivery weight changes appear to be continuously distributed (Fig. 1). The constants of the distributions are given (Table 4).

scholarly journals Delayed start of first-time breeding and non-breeders surplus in the Western Siberian population of the European Pied Flycatcher

2018 ◽  
Author(s):  
Vladimir G. Grinkov ◽  
Helmut Sternberg
Keyword(s):  
Demographic Data ◽  
Pied Flycatcher ◽  
First Year ◽  
Siberian Population ◽  
Lower Saxony ◽  
Factors Affecting ◽  
Experimental Removal ◽  
Widespread Belief ◽  
Males And Females ◽  
First Year Of Life

ABSTRACTNon-breeders are those sexually mature individuals that do not breed in a given reproductive cycle of a population. There is a widespread belief that the presence of non-breeders can affect the actual population dynamics, as well as the population responses to environmental change (Lee et al. 2017). Sternberg (1989), using demographic data, has shown that 83% and 62% of males and females, respectively, do not breed in the first year of life in the Lower Saxony (Germany) population of the European Pied Flycatcher (Ficedula hypoleuca). Later, with experimental removal of males, it has been proven that in the Lower Saxony and Moscow Region (Russia) populations, there are many non-breeding males (Sternberg et al. 2002). For the Netherlands population of the European Pied Flycatcher, the presence of a large number of non-breeders has been demonstrated using experimental removals for both males and females (Both et al. 2017). Here we have estimated the number of non-breeders in the Western Siberian population of the European Pied Flycatcher using demographic data (11 cohorts from 2001 to 2011 of birth) and experimental removal of males. We have shown that both males and females can start to breed at the age of one to five years. The proportion of non-breeders can be 59.5% and 68.5% for first-year males and females, respectively. We discuss the differences in the proportion of non-breeders between the Western Siberian and European populations of the European Pied Flycatcher, as well as factors affecting the number of non-breeders.

Statement on Infant Mortality

PEDIATRICS ◽  
1986 ◽  
Vol 78 (6) ◽  
pp. 1155-1160
Author(s):  
Keyword(s):  
Mortality Rate ◽  
Child Health ◽  
Infant Mortality ◽  
Neonatal Mortality ◽  
Mortality Rates ◽  
First Year ◽  
Postneonatal Mortality ◽  
Factors Affecting ◽  
Live Births ◽  
First Year Of Life

Why Is Infant Mortality Important? Rates of infant mortality are sensitive indicators of a broad range of factors affecting children's health. As such, infant mortality is the "tip of the iceberg" of child health problems, and changes in infant mortality are a signal of factors affecting child health more broadly. In addition to its role as a general gauge of child health, infant mortality itself represents an important health problem. It is well to remember that infant death rates are the highest of any age group less than 65 years. The message conveyed by infant mortality rates if better understood in terms of the causes of mortality at different times during the first year of life. Neonatal Mortality Neonatal mortality rate is defined as the number of infants dying between 0 and 27 days of life per 1,000 live births. These deaths in the first month of life reflect primarily factors associated with health of the mother before and during pregnancy and the special problems of the newborn. Deaths in this age range result chiefly from inadequate intruterine growth (prematurity, intrauterine growth retardation) and congenital anomalies. As a result, neonatal mortality rates provide an indicator of the factors affecting pregnancy, delivery, and the neonate and the adequacy of services in the prenatal, intrapartum, and neonatal periods. Postneonatal Mortality Postneonatal mortality rate is defined as the number of infants dying between 28 days and 11 months of life per 1,000 live births, ie, deaths occurring during the remainder of the first year of life.

Variability in First-Year Growth of Yellow Perch (Perca flavescens): Predictions from a Simple Model, Observations, and an Experiment

1994 ◽  
Vol 51 (11) ◽  
pp. 2501-2512 ◽  
Author(s):  
John R. Post ◽  
Donald J. McQueen
Keyword(s):  
Simple Model ◽  
Growth Rates ◽  
Yellow Perch ◽  
Explanatory Power ◽  
Perca Flavescens ◽  
Negative Relationship ◽  
Zooplankton Community ◽  
Prey Abundance ◽  
First Year ◽  
Growth Variability

First-year growth of yellow perch, Perca flavescens, varies by greater than an order of magnitude among populations and among cohorts within populations. The variability in growth rates of natural and enclosure-reared young-of-the-year yellow perch could be explained by the availability of benthic and/or plank-tonic prey (R2 = 0.093–0.098). Mean annual water temperature and cumulative degree-days did not add to the explanatory power of the relationships. The faster growing natural cohorts included more benthos in their diet; however, benthos is not necessary to sustain the highest growth rates because the fastest growth rates were observed in enclosure cohorts that lacked benthic invertebrates. Cohorts in lakes and enclosures that had a high proportion of Daphnia in the zooplankton community also supported higher first-year growth rates. The results of the enclosure experiment suggest that the dominant mechanism creating growth variability is density-dependent intra-age-class competition. Our empirical results, when coupled with a simple model, suggest that the assumption of a negative relationship between energetic costs of foraging and prey abundance, on a daily time scale, is the most appropriate because it acts to amplify growth variability across ranges of prey abundance.

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