Compensatory reactions of populations to stresses, and their evolutionary significance.

1954 ◽  
Vol 2 (1) ◽  
pp. 1 ◽  
Author(s):  
AJ Nicholson
Keyword(s):  
Population Density ◽  
Adverse Effects ◽  
Environmental Conditions ◽  
Lucilia Cuprina ◽  
Evolutionary Significance ◽  
Age Group ◽  
Evolutionary Progress ◽  
Compensatory Reaction ◽  
Compensatory Reactions

Cultures of Lucilia cuprina which were subjected to different kinds and intensities of stress automatically accommodated themselves to these stresses and maintained themselves in a state of balance under all the varied environmental conditions provided. Compensatory reaction always counteracted in some degree the adverse effects of the stresses to which the insects were subjected. Thus the persistent destruction of a particular age-group always caused more individuals to reach this age, so reducing the effects produced by destruction upon population density. It is shown that density governed compensatory reaction is a necessary counterpart of selection in evolutionary progress.

scholarly journals Gambaran Kasus Kematian pada Korban Terpapar Alkohol yang Diautopsi di Bagian Ilmu Kedokteran Forensik dan Medikolegal RSUP Prof. Dr. R. D. Kandou Periode 2014 - 2017

2018 ◽  
Vol 10 (3) ◽  
pp. 195
Author(s):  
Angela A. Pangemanan ◽  
James Siwu ◽  
Nola T. S. Mallo
Keyword(s):  
Retrospective Study ◽  
Alcohol Consumption ◽  
Adverse Effects ◽  
Cause Of Death ◽  
Human Body ◽  
Age Group ◽  
Addictive Substance ◽  
Using Data ◽  
Death Cases

Abstract: Alcohol is an addictive substance that could cause adverse effects to human body. Moreover, it is also related to a variety of criminal acts. North Celebes is one of the provinces with the highest alcohol consumption in Indonesia. This study was aimed to describe the death cases exposed to alcohol that were autopsied at Prof. Dr. R. D Kandou Hospital Manado during 2014-2017. This was a descriptive retrospective study using data of visum et repertum. The results showed that there were 17 death cases exposed to alcohol. The majority were in 2016 as many as 6 cases (35.3%). The most common age group was 26-35 years as many as 7 cases (41.2%). All cases were males (100%). The most cause of death in these cases were due to violence using sharp objects as many as 15 cases (88.2%). Conclusion: Most death cases exposed to alcohol were males aged 26-35 years, and the cause of death was violence using sharp object.Keywords: alcohol, death casesAbstrak: Alkohol adalah zat adiktif yang dapat berdampak buruk bagi tubuh manusia serta terkait juga dengan berbagai tindakan kriminalitas. Sulawesi Utara merupakan salah satu provinsi dengan konsumen alkohol terbanyak di Indonesia. Penelitian ini bertujuan untuk mengetahui gambaran kasus kematian pada korban terpapar alkohol yang diautopsi di RSUP Prof. Dr. R. D Kandou periode 2014-2017. Jenis penelitian ialah deskriptif retrospektif menggunakan data hasil visum et repertum. Jenis penelitian ialah deskriptif retrospektif. Hasil penelitian mendapatkan 17 kasus kematian korban terpapar alkohol. Kasus terbanyak pada tahun 2016 yaitu 6 kasus (35,3%). Kelompok usia terbanyak 26-35 tahun yaitu 7 kasus (41,2%) dan jenis kelamin laki-laki (100%). Penyebab kematian terpapar alkohol terbanyak karena kekerasan benda tajam yaitu 15 kasus (88,2%). Simpulan: Sebagian besar kasus kematian akibat terpapar alkohol berada dalam kelompok usia 26-35 tahun, semua berjenis kelamin laki-laki, dengan jenis penyebab kematian akibat kekerasan benda tajam.Kata kunci: alkohol, kasus kematian

scholarly journals Ornithocenosis Structure in Fresh and Wet Sudubravas of Kyiv Polissya during the Breeding Period

2016 ◽  
Vol 50 (3) ◽  
pp. 241-250
Author(s):  
A. V. Plyha
Keyword(s):  
Population Density ◽  
Age Groups ◽  
Bird Species ◽  
Pine Forests ◽  
Breeding Period ◽  
Ecological Group ◽  
Ecological Groups ◽  
Age Group ◽  
Majority Population ◽  
Species Lists

Abstract This research was carried out in Kyiv Polissya geobotanical province, in one of most common woods type - fresh and wet sudubravas. Its purpose is to determine ornithocenosis structure in different age groups of this type of forest. To achieve that, forest bird species lists were composed, their population density and that of ecological groups of birds were calculated. In the course of the research in the breeding periods of 2013-2014, two-time surveys were carried out on 12 survey routes of total length 33 km. For further analysis, forests were divided into age groups: 0-20 years, 20-40 years, 40-60 years, 60-80 years, 80-100 years and forests over 100 years. Altogether 53 bird species were found. Species lists were poorest in the forests of 0-20 years (18 species), and richest in the forests over 100 years (39 species). Minimal population density was 473 individuals per square kilometer in the youngest forest age group of 0-20 years, maximal - 2155 individuals per square kilometer in pine forests aged over 100 years. Analysis of different population densities of ecological groups reveals steadily growing numbers of hollow-nesting birds and tree-nesting birds in accordance with aging of the forests. In older forests hollow-nesting birds constitute an absolute majority. Population density of another ecological group shows no such direct tendency.

scholarly journals Adolescent endometriosis

2017 ◽  
Vol 6 (8) ◽  
pp. 3213
Author(s):  
Meenu P. Nanthakumar ◽  
Sendhil C. Arumugam
Keyword(s):  
Adverse Effects ◽  
Pelvic Pain ◽  
Chronic Pelvic Pain ◽  
Reproductive Age ◽  
Age Group ◽  
Women Of Reproductive Age ◽  
Surgical Options ◽  
Reproductive Age Group

Endometriosis is predominantly a disease of women of reproductive age group. Endometriosis is not uncommon in adolescents. Presentation tends to focus on pain, especially intractable dysmenorrhea and chronic pelvic pain. In around 60% of patients with endometriosis symptoms start in adolscence. Pain unresponsive to treatment is the usual indication for a Laproscopy. The appearance of endometriotic lesions is different from that of adults. Medical and surgical options for treatment are available. Endometriosis may be progressive and adverse effects may go beyond pain and cause infertility.

Model gospodarowania populacją jelenia europejskiego Cervus elaphus L. w Wolińskim Parku Narodowym i na Wyspie Wolin

2018 ◽  
Vol XI ◽  
pp. 81-90
Author(s):  
Adam Mohr ◽  
Antoni Przybylski ◽  
Małgorzata Zimnicka – Pluskota ◽  
Damian Spieczyński
Keyword(s):  
Population Density ◽  
Population Growth ◽  
Cervus Elaphus ◽  
Environmental Conditions ◽  
Red Deer ◽  
Actual State ◽  
Model Population ◽  
Deer Population ◽  
Proposed Model ◽  
Age And Sex

The paper presents the current methods of management and environmental conditions of the functioning of red deer population on the Wolin Island. The inventory carried out in 2014 using the drive census method revealed the prevalence of stags in the population (0.86 hinds/1stag) and the population density of 225 individuals/1,000 hectares of the forest, whereas harvest conducted in this season showed merely 22 individuals/1,000 hectares. In the analysed seasons before the inventory, harvest was also low (about 10% of the probable actual state) and despite harvesting mainly hinds, it did not curb the population growth. In the years 2006 – 2014, the yearly harvest in the largest hunting district fluctuated within the range of 14.5 to 60.5, x̅=27.0 individuals/1,000 hectares (n=9), while in the remaining four smaller population management units, the average yearly harvest amounted to only 0.2 to 9.8 individuals/1,000 hectares (n=9). The realized rate of population growth determined by the method of summer deer observation in 2015 amounted to 42.2% of the hinds number. Applying the simulation of the model population meeting the parameters indicated in the inventory, the researchers calculated and proposed the optimal indicators of harvesting individual age and sex groups. The proposed model of hunting monitoring and management assumes optimization of environmental conditions, structure and size of the actual population within the next 10 years.

An outline of the dynamics of animal populations.

1954 ◽  
Vol 2 (1) ◽  
pp. 9 ◽  
Author(s):  
AJ Nicholson
Keyword(s):  
Stationary State ◽  
Natural Enemies ◽  
Environmental Conditions ◽  
Intraspecific Competition ◽  
Density Change ◽  
Equilibrium Density ◽  
Population Densities ◽  
Compensatory Reaction ◽  
Animal Populations ◽  
Intensity Of Competition

This article is itself a summarized statement concerning the various influences which affect population densities and the population systems these lead to. Known facts concerning animal populations have been analysed. systematized. and critically examined. using the experimental and mathematical approaches in the simpler situations. The more outstanding conclusions are listed below. Populations are self-governing systems. They regulate their densities in relation to their own properties and those of their environments. This they do by depleting and impairing essential things to the threshold of favourability, or by maintaining reactive inimical factors, such as the attack of natural enemies, at the limit of tolerance. The mechanism of density governance is almost always intraspecific competition, either amongst the animals for a critically important requisite, or amongst natural enemies for which the animals concerned are requisites. Governing reaction induced by density change holds populations in a state of balance in their environments. The characteristic of balance is sustained and effective compensatory reaction which maintains populations in being in spite of even violent changes in the environment, and which adjusts their densities in general conformity with prevailing conditions. Far from being a stationary state, balance is commonly a state of oscillation about the level of the equilibrium density which is for ever changing with environmental conditions. Destructive factors do not add to mortality when they continue to operate over long periods, but merely cause a redistribution of mortality, for the intensity of competition automatically relaxes sufficiently to make room for the destruction they cause. Such compensatory reaction causes the effect of destructive factors upon density to be much less when balance is reattained than that which they produce when they first operate.

scholarly journals Local Government Forestry Expenditure and Forest Land Cover: A Preliminary Lesson from Decentralized Indonesia

2017 ◽  
Vol 62 (3) ◽  
pp. 127
Author(s):  
Firda Hidayati ◽  
Yogi Vidyattama ◽  
Cameron Gordon
Keyword(s):  
Population Density ◽  
Land Cover ◽  
Population Growth ◽  
Environmental Conditions ◽  
Forest Cover ◽  
Negative Association ◽  
Forest Land ◽  
Negative Change ◽  
Wood Extraction ◽  
Forest Land Cover

Even though government of Indonesia invests billions of rupiah to tackle deforestation, its effectiveness has been questionable. This study analyses changes in rates of forest cover in Indonesia and their association with forestry expenditures (FE) spent by the provincial governments. Based on 2007 to 2010 data, linear multiple regression results indicate that FE is not enough to tackle the negative change in forest land cover that could represent deforestation. Moreover, it was found that FE have negative association with forest land cover and therefore, can be associated to deforestation. This negative association remains when other factors that affect forest land cover such as wood extraction, agriculture outcome, forestry outcome, population growth and population density and initial environmental conditions have been controlled.AbstrakWalaupun pemerintah Indonesia telah menginvestasikan trilyunan rupiah untuk mengurangi deforestasi, akan tetapi efektifitasnya dipertanyakan. Penelitian ini menganalisa tingkat perubahan luasan tutupan hutan di Indonesia and asosiasinya dengan Pengeluaran Sektor Kehutanan (PSK) yang dibelanjakan oleh pemerintah provinsi. Berdasar data tahun 2007 sampai 2010, hasil regresi multiple linier mengindikasikan bahwa PSK tidak cukup untuk mengurangi akibat negatif dalam perubahan hutan dan lahan yang dapat mngakibatkan deforestasi. Lebih lanjut, ditemukan bahwa PSK berhubungan erat pengurangan luasan hutan, yang dapat dikaitkan dengan deforestasi. Asososiasi yang negatif ini tetap terjadi walaupun faktor lain yang memengaruhi tutupan hutan seperti penebangan kayu, hasil pertanian, hasil kehutanan, pertumbuhan populasi dan kepadatan populasi dan kondisi awal lingkungan telah dikontrol.Kata kunci: Deforestasi, Hutan Tropis; Populasi Penduduk; Tutupan Hutan; Pengeluaran untuk Reboisasi HutanJEL classifications: E62; Q58; H76

scholarly journals Causes and consequences of variation in early-life telomere length in a bird metapopulation

2021 ◽  
Author(s):  
Michael Le Pepke ◽  
Thomas Kvalnes ◽  
Peter Sjolte Ranke ◽  
Yimen G. Araya-Ajoy ◽  
Jonathan Wright ◽  
...  
Keyword(s):  
Reproductive Success ◽  
Population Density ◽  
Telomere Length ◽  
Environmental Conditions ◽  
Early Life ◽  
Morphological Traits ◽  
Weather Conditions ◽  
Population Fluctuations ◽  
Individual Quality ◽  
Pace Of Life

1.Environmental conditions during early-life development can have lasting effects on individual quality and fitness. Telomere length (TL) may correlate with early-life conditions and may be an important mediator or biomarker of individual quality or pace-of-life, as periods of increased energy demands can increase telomere attrition due to oxidative stress. Thus, knowledge of the mechanisms that generate variation in TL, and the relation between TL and fitness, is important in understanding the role of telomeres in ecology and life-history evolution. 2.Here, we investigate how environmental conditions and morphological traits are associated with early-life TL and if TL predicts natal dispersal probability or components of fitness in two populations of wild house sparrows (Passer domesticus). 3.We measured morphological traits and blood TL in 2746 nestlings from 20 cohorts (1994-2013) and retrieved data on weather conditions. We monitored population fluctuations, and individual survival and reproductive output using field observations and genetic pedigrees. We then used generalized linear mixed-effects models to test which factors affected TL in early-life, and if TL predicted dispersal propensity, or was associated with recruitment probability, mortality risk, or reproductive success.4.We found a negative effect of population density on TL, but only in one of the populations. There was a curvilinear association between TL and the maximum daily North Atlantic Oscillation (NAO) index during incubation, suggesting that there are optimal weather conditions that result in the longest TL. Dispersers tended to have shorter telomeres than non-dispersers. TL did not predict survival, but we found a tendency for individuals with short telomeres to have higher annual reproductive success.5.Our study showed how early-life TL is shaped by effects of growth, weather conditions and population density, supporting that environmental stressors negatively affect TL in wild populations. In addition, TL may be a mediator or biomarker of individual pace-of-life, with higher dispersal rates and annual reproduction tending to be associated with shorter early-life TL in this study. However, clear associations between early-life TL and individual fitness seems difficult to establish and may differ between different populations in the wild.

scholarly journals Localized pustular psoriasis in a child treated successfully with topical dapsone gel

2021 ◽  
Author(s):  
Vidya Kharkar ◽  
Surender Singh ◽  
Yallappa Ramachandrappa Kabbannavar
Keyword(s):  
Adverse Effects ◽  
Plaque Psoriasis ◽  
Paediatric Population ◽  
Common Type ◽  
Effective Therapy ◽  
Pustular Psoriasis ◽  
Age Group ◽  
Immune Mediated ◽  
Paediatric Age ◽  
Erythrodermic Psoriasis

<p class="abstract">Psoriasis is a chronic inflammatory, immune mediated dermatosis in children and adults. About one third of cases affected with psoriasis have their onset in first and second decade of life. Of paediatric population, about 0.5-2% is affected, infants are rarely affected. Overall plaque psoriasis is most common type followed by guttate and pustular psoriasis. Treating severe forms of psoriasis such as pustular psoriasis and erythrodermic psoriasis can pose difficulties, especially in paediatric population. Hence paediatric psoriasis needs to be managed effectively, however effective therapy also poses the risk of producing adverse effects, more so in paediatric age group. We report a case of localized pustular psoriasis, with an antineutrophil agent which is much safer and may target directly the pathophysiology of pustular psoriasis.</p>

scholarly journals Incidence and Case-Fatality Ratio of COVID-19 infection in relation to Tobacco Smoking, Population Density and Age Demographics in the USA: could Particulate Matter derived from Tobacco Smoking act as a Vector for COVID-19 transmission?

2020 ◽  
Author(s):  
Yves Muscat Baron
Keyword(s):  
Particulate Matter ◽  
Population Density ◽  
Tobacco Smoking ◽  
Case Fatality ◽  
The State ◽  
Smoking Ban ◽  
Age Group ◽  
Case Fatality Ratio ◽  
Significant Difference ◽  
The Usa

ABSTRACTBACKGROUNDTobacco smoking is known to increase the risk for bacterial and viral respiratory infections and this also applies to second-hand smoking. Smoking has been shown to increase the severity of COVID-19 infection and the consequent risk for intra-tracheal ventilation in smokers. Tobacco smoking exposes the user and nearby individuals to very high concentrations of particulate matter in a short period of time. Genes appertaining to COVID-19 have been found adherent to particulate matter. Particulate matter has been shown to travel beyond the social distance of 2 metres up to 10 metres. COVID-19 related mortality has been linked to elevated atmospheric levels of the particulate matter, PM2.5. The aim of the study was to observe the incidence of infection rate and case fatality ratios in the USA, comparing States with partial bans on tobacco smoking, to States with more restrictive smoking regulation, exploring a possible link between smoke-related particulate matter and COVID-19 transmission.METHODOLOGYTwo groups of USA States, differentiated by the degree of smoking legislative restrictions, had a number of variables compared. The incidence of COVID-19 infection, case-fatality ratio and testing frequency were obtained from the John Hopkins Coronavirus Resource Centre. The degree of smoking bans in the USA States was obtained from the websites of the Nonsmokers Rights Foundation. The percentage of the State population which smokes was collected from the Centres of Disease Control database. Population density, Body Mass Index and population percentages of individuals 65+/75+years were obtained from databases concerning USA demographics.RESULTSWith the available data there was no significant difference in COVID-19 testing prevalence between the partial smoking ban group and the more restrictive regulated group. The incidence of COVID-19 infection in the States with limited bans on tobacco smoking was 2046/100,000 (sd+/-827) while the infection incidence in States with more restrictive rulings on tobacco smoking was 1660/100,000 (sd+/-686) (p<0.038). The population percentage of smokers in States with minor limitations to smoking was 18.3% (sd+/-3.28), while States with greater smoking restrictions had a smoking population percentage of 15.2% (sd+/-2.68) (p<0.0006).The two populations of both groups did not differ numerically (p<0.24) and numbered 157,820,000 in the partial smoking ban group and 161,439,356 in the more restrictive group. Population density correlated significantly with the case-fatality ratio (R=0.66 p<0.0001), as did the 75+year age group (R=0.29 p<0.04). Reflecting the possibility of trans-border transmission, the smoking status of adjacent partial smoking ban States may influence the COVID-19 incidence of bordering States (e.g. Utah) even if the smoking regulations of the latter were stricter than the former.Other factors that could impact the COVID-19 pandemic in the USA such as the State case-fatality ratio, population density, population percentage with elevated body mass index and the percentage of the state population aged 65years or above did not show any significant difference between both groups of States.CONCLUSIONStates in the USA with high levels of tobacco smoking and limited regulation had significantly higher rates of COVID-19 infection incidences than States with greater smoking restrictions. Population density and the age group of 75+years, showed a positive significant correlation with the case-fatality ratio. Besides the adverse effects of tobacco smoking on pulmonary defences, it would be interesting to explore the possibility of infection transmission via coronavirus-laden particulate matter from exhaled fumes derived from tobacco smoking.

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