Practical Application of the Stable Age Distribution: Analysis of a Tetranychid Mite (Acari: Tetranychidae) Population Outbreak

1983 ◽  
Vol 12 (1) ◽  
pp. 10-18 ◽  
Author(s):  
J. R. Carey
Keyword(s):  
Age Distribution ◽  
Distribution Analysis ◽  
Practical Application ◽  
Tetranychid Mite ◽  
Stable Age Distribution ◽  
Population Outbreak

scholarly journals STUDI LALAT PENGOROK DAUN LIRIOMYZA SPP. PADA PERTANAMAN BAWANG DAUN, DAN PARASITOID OPIUS CHROMATOMYIAE BELOKOBYLSKIJ & WHARTON (HYMENOPTERA: BRACONIDAE)

2009 ◽  
Vol 9 (1) ◽  
pp. 22-31
Author(s):  
Rusli Rustam ◽  
Aunu Rauf ◽  
Nina Maryana ◽  
Pudjianto Pudjianto ◽  
Dadang Dadang
Keyword(s):  
Age Distribution ◽  
Host Density ◽  
Field Studies ◽  
Reproductive Value ◽  
Laboratory Studies ◽  
Demographic Parameter ◽  
Liriomyza Huidobrensis ◽  
Stable Age Distribution ◽  
Net Reproduction ◽  
Density Results

Studies on Leafminer Liriomyza spp. in Green Onion Fields, and Parasitoid Opius chromatomyiae Belokobylskij & Wharton (Hymenoptera: Braconidae).  Field studies were conducted to determine population abundance of leafminers and their parasitoids in green onion fields in Puncak, West Java. In addition to that, laboratory studies were carried out to determine demographic parameter of Opius chromatomyiae as well as response of parasitoid to increasing host density. Results revealed that green onions were infested by two species of leafminers, Liriomyza huidobrensis and Liriomyza chinensis.  Leafminer flies emerged from Erwor leaves (54.5) were significantly higher than those of RP leaves (18.65) (P = 0.0005). However, number of  leafminer flies caught on sticky traps was not statistically different (P = 0.297).  Two species of parasitoid, Hemiptarsenus varicornis and O. chromatomyiae, were associated with leafminers in green onion fields. Higher number of parasitoids emerged from Erwor leaves (13.68) as compared to RP (6.90) (P =0.0007 ). However, level of parasitization were 24.36% on Erwor and 28.45% on RP, and was not significantly different (P = 0.387). Laboratory studies indicated that net reproduction (Ro) of O. chromatomyiae was 28.55, generation time (T) 15.96 days, intrinsic growth rate 0.21, and total of reproductive value 223.64.  The stable age distribution of parasitoid were 37.93% eggs, 24.92% larvae, 20.36% pupae and 16.78% adults.  The parasitoid showed functional response type II to increasing host density, with a = 0.08 and Th = 2.58.

scholarly journals Network and Evolutionary Analysis of Human Epigenetic Regulators to Unravel Disease Associations

Genes ◽  
2020 ◽  
Vol 11 (12) ◽  
pp. 1457
Author(s):  
Shinji Ohsawa ◽  
Toshiaki Umemura ◽  
Tomoyoshi Terada ◽  
Yoshinori Muto
Keyword(s):  
Positive Selection ◽  
Developmental Stages ◽  
Age Distribution ◽  
System Level ◽  
Disease Genes ◽  
Evolutionary Analysis ◽  
Distribution Analysis ◽  
Cancer Disease ◽  
High Tendency ◽  
Epigenetic Regulators

We carried out a system-level analysis of epigenetic regulators (ERs) and detailed the protein–protein interaction (PPI) network characteristics of disease-associated ERs. We found that most diseases associated with ERs can be clustered into two large groups, cancer diseases and developmental diseases. ER genes formed a highly interconnected PPI subnetwork, indicating a high tendency to interact and agglomerate with one another. We used the disease module detection (DIAMOnD) algorithm to expand the PPI subnetworks into a comprehensive cancer disease ER network (CDEN) and developmental disease ER network (DDEN). Using the transcriptome from early mouse developmental stages, we identified the gene co-expression modules significantly enriched for the CDEN and DDEN gene sets, which indicated the stage-dependent roles of ER-related disease genes during early embryonic development. The evolutionary rate and phylogenetic age distribution analysis indicated that the evolution of CDEN and DDEN genes was mostly constrained, and these genes exhibited older evolutionary age. Our analysis of human polymorphism data revealed that genes belonging to DDEN and Seed-DDEN were more likely to show signs of recent positive selection in human history. This finding suggests a potential association between positive selection of ERs and risk of developmental diseases through the mechanism of antagonistic pleiotropy.

scholarly journals The long-term effects of the Amoco Cadiz oil spill

1982 ◽  
Vol 297 (1087) ◽  
pp. 323-333 ◽  
Keyword(s):  
Salt Marshes ◽  
Age Distribution ◽  
Life Cycles ◽  
Long Term Effects ◽  
Delayed Effects ◽  
Sea Birds ◽  
Stable Age Distribution ◽  
Rot Disease ◽  
One Year

The supertanker Amoco Cadiz wrecked on the coast of northern Brittany in April 1978. The resulting spill of 223000 t of crude oil polluted some 360 km of rocky or sandy shores, salt marshes and estuaries. An immediate mortality impact was observed. Populations of bivalves, periwinkles, limpets, peracarid crustaceans, heart urchins and sea birds were the most severely affected. Populations of polychaete worms, large crustaceans and coastal fishes were less affected. Three to six generations (5—10 years for bivalves but up to 60 years for birds) may be necessary before populations retrieve their stable age distribution. Delayed effects on mortality, growth and recruitment were still observed up to 3 years after the spill. Estuarine flat fishes and mullets had reduced growth, fecundity and recruitment; they were affected by fin rot disease. Populations of clams and nematodes in the meiofauna declined one year after the spill. Weathered oil is still present in low-energy areas. Species with short life cycles tend to replace long-lived species. A fauna of cirratulid and capitellid polychaete worms now prevails in sandy to m uddy areas. For several clam populations, recruitment remains unstable. Three years after the spill it is still premature to decide how long it will take before populations and ecosystems reach their former or new equilibria.

Orientation distribution analysis in deformed grains

2001 ◽  
Vol 34 (3) ◽  
pp. 280-288 ◽  
Author(s):  
Jean Christophe Glez ◽  
Julian Driver
Keyword(s):  
Statistical Analysis ◽  
Aluminium Alloy ◽  
Orientation Distribution ◽  
Distribution Functions ◽  
Distribution Analysis ◽  
Practical Application ◽  
Orientation Data ◽  
Alloy Crystal ◽  
Orientation Distribution Functions ◽  
Individual Grains

Some improvements are proposed for the statistical analysis of orientation data within individual grains, in particular by allowing for crystallographic symmetries. A method based on quaternions is then presented to characterize orientation spreads including anisotropic effects. Based on this approach, some analyses of disorientation distributions (orientation distribution functions, disorientation noise and the description of sub-boundary disorientation) are reconsidered. The analysis is illustrated by a practical application to the microtextures of a hot deformed aluminium alloy crystal.

Chapter 1: Theoretical Foundations

1973 ◽  
Vol 27 ◽  
pp. 6-10 ◽  
Author(s):  
Kenneth M. Weiss
Keyword(s):  
Age Distribution ◽  
Human Populations ◽  
Stable Form ◽  
Stable Age Distribution ◽  
Theoretical Population ◽  
Stable Population Theory ◽  
Number Of Individuals ◽  
Theoretical Foundations ◽  
Stable Populations

The approach to population structure followed in this work is that of stable population theory as developed by A. J. Lotka and others. An early exposition of this theory is found in Lotka (1956); more recently it has been summarized by Coale (1972), Keyfitz (1968), and Shryock and Siegel(1971).The theory of stable populations requires that a population is infinite in size, has no net immigration or outmigration, and has fixed rates of fertility and mortality at each age. These assumptions are often approximated closely enough by real populations for the theory to be useful. Given the stated conditions, a population is described by its age distribution, or the number of individuals at each age. Since the theoretical population is infinite, the age distribution is defined in terms of relative numbers or percentages rather than finite numbers of individuals at each age.The age structure is determined by the rates of mortality and fertility. It has been proved by Lotka that, no matter what the initial age distribution, a population under these assumptions approaches a certain age distribution which is determined by those rates. The result is the so-called stable age distribution since it will no longer change if mortality and fertility remain fixed. In fact, a temporary perturbation in these rates will only temporarily disturb the age distribution, which will quickly return to the stable form. Human populations approach the stable age distribution in well under 100 yr after the rates become fixed.

Stable Age Distribution

2016 ◽  
Author(s):  
Monica Nordberg ◽  
Douglas M. Templeton ◽  
Ole Andersen ◽  
John H. Duffus
Keyword(s):  
Age Distribution ◽  
Stable Age Distribution

scholarly journals Group C rotavirus infection in patients with acute gastroenteritis in outbreaks in western India between 2006 and 2014

2016 ◽  
Vol 145 (2) ◽  
pp. 310-315 ◽  
Author(s):  
M. S. JOSHI ◽  
V. M. JARE ◽  
V. GOPALKRISHNA
Keyword(s):  
Rural Areas ◽  
Acute Gastroenteritis ◽  
Urban Areas ◽  
Severe Disease ◽  
Age Distribution ◽  
Clinical Severity ◽  
Western India ◽  
Distribution Analysis ◽  
Group C Rotavirus ◽  
Vp6 Gene

SUMMARYFaecal specimens collected from outbreak (n = 253) and sporadic (n = 147) cases of acute gastroenteritis that occurred in western India between 2006 and 2014 were tested for group C rotavirus (GCR) using partial VP6 gene-based RT–PCR. All specimens were tested previously for the presence of other viral and bacterial aetiological agents by conventional methods. The rate of GCR detection was 8·6% and 0·7% in outbreak and sporadic cases, respectively. GCR infections prevailed in outbreaks reported from rural areas (10·9%) compared to urban areas (1·6%). Clinical severity score of the patients with GCR infection (n = 23) indicated severe disease in the majority (70%) of cases. The age distribution analysis indicated 52·1% of GCR infections in children aged <10 years. The male:female ratio in GCR-positive patients was 2·3:1. Of the 23 GCR-positive cases, 17 (73·9%) had a sole GCR infection and six had mixed infections with other viral and/or bacterial agents. Phylogenetic analysis of nucleotide sequences classified GCR strains of the study in to I2 genotype of the VP6 gene. This is the first study to show the occurrence of GCR in gastroenteritis outbreaks in India.

scholarly journals Outcome of primary pulmonary salivary gland-type carcinoma

2021 ◽  
Vol 156 (Supplement_1) ◽  
pp. S150-S150
Author(s):  
P Q Deb ◽  
D Suster
Keyword(s):  
Overall Survival ◽  
Salivary Gland ◽  
Lung Carcinoma ◽  
Minor Salivary Gland ◽  
Age Distribution ◽  
Distribution Analysis ◽  
Epidemiological Features ◽  
Age Of Diagnosis ◽  
Gland Type ◽  
Disease Specific

Abstract Introduction/Objective Primary pulmonary salivary gland-type carcinomas are rare malignancies that arise from minor salivary gland tissue present within seromucinous submucosal glands within the lower respiratory tract. Due to their rarity (~ &lt;1% of all primary lung malignancies), the epidemiological features and outcome of these malignancies are not well documented. Data from the National Cancer Institute’s Surveillance, Epidemiology, and End Results (SEER) database was analyzed to identify cases of primary pulmonary salivary gland carcinoma. The most common tumor types included mucoepidermoid carcinoma (MEC), adenoid cystic carcinoma (ADCC), and epithelial-myoepithelial carcinoma (EMEC). The tumors were analyzed for overall survival across various epidemiological factors. Methods/Case Report All patients diagnosed with MEC, ADCC, and EMEC with the lung designated as the primary site between the period of 1975 to 2017 were analyzed. We calculated overall survival and disease-specific survival with Kaplan-Meier curves and Cox proportional hazards models using SPSS v25. Results (if a Case Study enter NA) 323 cases of MEC, 284 cases of ADCC, and 6 cases of EMEC diagnosed as primary lung carcinoma were identified. Age distribution analysis of the patients showed a unimodal distribution for both MEC and ADCC with most patients being diagnosed after the age of 40. 54% of MEC patients were male, while 48% of ADCC patients were male. The majority of patients were Caucasians (77% for MEC and 83% for ADCC patients). Both disease-specific and overall survival were worse for patients diagnosed at the age of 60 years or above. Race or sex did not significantly affect patients’ survival. High-grade MEC showed significantly worse prognosis than low or intermediate grade MEC. EMEC cases were too few (n=6) to perform reliable survival analysis, however, the age of diagnosis was higher (45 and above) with a higher incidence among black population (50%). Conclusion Comprehensive review of clinical and epidemiological features of primary salivary gland-type lung carcinoma show that the age of diagnosis and tumor grade are the most significant factor in determining the survival of these patients.

Exponential growth of a branching process usually implies stable age distribution

1979 ◽  
Vol 16 (03) ◽  
pp. 651-656
Author(s):  
Bo Berndtsson ◽  
Peter Jagers
Keyword(s):  
Population Size ◽  
Exponential Function ◽  
Exponential Growth ◽  
Branching Process ◽  
Age Distribution ◽  
Length Distribution ◽  
Random Variables ◽  
Stable Age Distribution

Start a Bellman–Harris branching process from one or several ancestors, whose ages are identically distributed random variables. Assume that the life-length distribution decays more quickly than exponentially and that the distribution of ages at start does not give too much mass to high ages (in a sense to be made precise). Then, if the expected population size is an exponential function of time, the ages must follow the stable age distribution of the process.

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