scholarly journals Youth in the study of comparative physiology: insights from demography in the wild

2020 ◽  
Author(s):  
Richard W. Hill ◽  
David A. Sleboda ◽  
Justin J. Millar
Keyword(s):  
Natural Populations ◽  
Natural World ◽  
Early Age ◽  
Type I ◽  
Empirical Knowledge ◽  
Comparative Physiology ◽  
Stage Of Development ◽  
Animal Populations ◽  
In The Wild ◽  
First Time

Abstract Of all the properties of individual animals of interest to comparative physiologists, age and stage of development are among the most consequential. In a natural population of any species, the survivorship curve is an important determinant of the relative abundances of ages and stages of development. Demography, thus, has significant implications for the study of comparative physiology. When Edward Deevey published his influential summary of survivorship in animal populations in the wild seven decades ago, he emphasized “serious deficiencies” because survivorship curves for natural populations at the time did not include data on the earliest life stages. Such data have accumulated over intervening years. We survey, for the first time, empirical knowledge of early-age survivorship in populations of most major animal groups in a state of nature. Despite wide variation, it is almost universally true that > 50% of newly born or hatched individuals die before the onset of sexual maturity, even in species commonly assumed to exhibit high early-age survivorship. These demographic facts are important considerations for studies in comparative and environmental physiology whether physiologists (i) aim to elucidate function throughout the life cycle, including both early stages and adults, or (ii) focus on adults (in which case early-age survivorship can potentially affect adult characteristics through selection or epigenesis). We establish that Deevey’s Type I curve (which applies to species with relatively limited early mortality) has few or no actual analogs in the real, natural world.

scholarly journals Evolution of quantitative traits in the wild: mind the ecology

2010 ◽  
Vol 365 (1552) ◽  
pp. 2431-2438 ◽  
Author(s):  
Josephine M. Pemberton
Keyword(s):  
Quantitative Genetics ◽  
Quantitative Traits ◽  
Natural Populations ◽  
Response To Selection ◽  
Genetic Response ◽  
Quantitative Genetic ◽  
Animal Populations ◽  
In The Wild ◽  
Gradient Variation

Recent advances in the quantitative genetics of traits in wild animal populations have created new interest in whether natural selection, and genetic response to it, can be detected within long-term ecological studies. However, such studies have re-emphasized the fact that ecological heterogeneity can confound our ability to infer selection on genetic variation and detect a population's response to selection by conventional quantitative genetics approaches. Here, I highlight three manifestations of this issue: counter gradient variation, environmentally induced covariance between traits and the correlated effects of a fluctuating environment. These effects are symptomatic of the oversimplifications and strong assumptions of the breeder's equation when it is applied to natural populations. In addition, methods to assay genetic change in quantitative traits have overestimated the precision with which change can be measured. In the future, a more conservative approach to inferring quantitative genetic response to selection, or genomic approaches allowing the estimation of selection intensity and responses to selection at known quantitative trait loci, will provide a more precise view of evolution in ecological time.

Reproductive Organ Education for Psychic Health Development of Early Age

2018 ◽  
Vol 2 ◽  
Author(s):  
Dwi Darwati
Keyword(s):  
Early Childhood ◽  
Early Childhood Development ◽  
Deviant Behavior ◽  
Reproductive Organs ◽  
Reproductive Organ ◽  
The Body ◽  
Childhood Development ◽  
Early Age ◽  
Digital Era ◽  
Stage Of Development

Reproductive  health education should be given since early childhood by using language that is adapted to the stage of development. If you procrastinate and wait until the teenager it is already too late because in the days of the digital era, as now, all the information can be easily accessed by anyone including children early age. If the early childhood misinformed about their reproductive organs it would disrupt the physical and psychological development due to the wrong behavior in caring for and maintaining reproductive organs. Qur’an as the holy book of Muslims describes the steps of reproduction and  imparting education wisely as well as how to apply such education. This kind of education must be in accordance with the conditions of children and there should not be a lie about it We can also use media and methods such as pictures, songs, tap or other visual  media which can give clearer information, so that children can clearly see parts of the body, their characteristics, and how to treat and care them. The impropriate approach in conveying this kind of knowledge will be very dangerous for children. The provision of early age reproductive organs education can prevent the occurrence of deviant behavior as well as protect children from dangerous influence in early childhood development.

Dwindling status of Epimedium Elatum (Morren & Decne) and its geographical distribution in Kashmir Himalaya, India

2018 ◽  
pp. 47-52
Keyword(s):  
Medicinal Plant ◽  
Biological Activities ◽  
Conservation Status ◽  
Natural Populations ◽  
Culture Techniques ◽  
Kashmir Himalayas ◽  
Near Future ◽  
First Time ◽  
Tissue Culture Techniques

Epimedium elatum (Morren & Decne) of family Berberidaceace is a rare perennial medicinal plant, endemic to high altitude forests of Northwestern Himalayas in India. Ethnobotanically, it has been used as an ingredient for treatment of bone-joint disorders, impotence and kidney disorders in Kashmir Himalayas. Phytochemically, it is rich in Epimedin ABC and Icariin; all of these have been demonstrated to possess remarkable biological activities like PDE-5 inhibition (treatment of erectile dysfunction), anticancer, antiosteoporosis antioxidant and antiviral properties. The present investigation reports its traditional usage, comprehensive distribution and conservation status from twenty ecogeographical regions in Kashmir Himalayas, India. The species was reported from Gurez valley for the first time. Numerous threats like excessive grazing, deforestration, habitat fragmentation, tourism encroachment, landslides and excessive exploitation have decreased its natural populations in most of the surveyed habitats. Consequently, its existence may become threatened in near future if timely conservation steps are not taken immediately by concerned stakeholders involved in medicinal plant research. Moreover, use of plant tissue culture techniques is recommended for development of its in vitro propagation protocols. Therefore, introduction of this medicinal plant in botanical gardens, protected sites and development of monitoring programmes are needed for its immediate conservation in Northwestern Himalayas, India.

scholarly journals Estimation of Parameters of Deleterious Mutations in Partial Selfing or Partial Outcrossing Populations and in Nonequilibrium Populations

Genetics ◽  
2000 ◽  
Vol 154 (4) ◽  
pp. 1893-1906 ◽  
Author(s):  
Jian Li ◽  
Hong-Wen Deng
Keyword(s):  
Computer Simulations ◽  
Natural Populations ◽  
Deleterious Mutations ◽  
Selfing Rate ◽  
Estimation Of Parameters ◽  
Animal Populations ◽  
Rapid Pace ◽  
Dynamics Of Populations ◽  
Mutation And Selection

Abstract The Deng-Lynch method was developed to estimate the rate and effects of deleterious genomic mutations (DGM) in natural populations under the assumption that populations are either completely outcrossing or completely selfing and that populations are at mutation-selection (M-S) balance. However, in many plant and animal populations, selfing or outcrossing is often incomplete in that a proportion of populations undergo inbreeding while the rest are outcrossing. In addition, the degrees of deviation of populations from M-S balance are often not known. Through computer simulations, we investigated the robustness and the applicability of the Deng-Lynch method under different degrees of partial selfing or partial outcrossing and for nonequilibrium populations approaching M-S balance at different stages. The investigation was implemented under constant, variable, and epistatic mutation effects. We found that, generally, the estimation by the Deng-Lynch method is fairly robust if the selfing rate (S) is <0.10 in outcrossing populations and if S > 0.8 in selfing populations. The estimation may be unbiased under partial selfing with variable and epistatic mutation effects in predominantly outcrossing populations. The estimation is fairly robust in nonequilibrium populations at different stages approaching M-S balance. The dynamics of populations approaching M-S balance under various parameters are also studied. Under mutation and selection, populations approach balance at a rapid pace. Generally, it takes 400–2000 generations to reach M-S balance even when starting from homogeneous individuals free of DGM. Our investigation here provides a basis for characterizing DGM in partial selfing or outcrossing populations and for nonequilibrium populations.

scholarly journals Modular invariant models of leptons at level 7

2020 ◽  
Vol 2020 (8) ◽  
Author(s):  
Gui-Jun Ding ◽  
Stephen F. King ◽  
Cai-Chang Li ◽  
Ye-Ling Zhou
Keyword(s):  
Modular Forms ◽  
Galois Field ◽  
Special Linear Group ◽  
Type I ◽  
Time Level ◽  
Projective Special Linear Group ◽  
Modular Invariant ◽  
Seesaw Mechanism ◽  
Linearly Independent ◽  
First Time

Abstract We consider for the first time level 7 modular invariant flavour models where the lepton mixing originates from the breaking of modular symmetry and couplings responsible for lepton masses are modular forms. The latter are decomposed into irreducible multiplets of the finite modular group Γ7, which is isomorphic to PSL(2, Z7), the projective special linear group of two dimensional matrices over the finite Galois field of seven elements, containing 168 elements, sometimes written as PSL2(7) or Σ(168). At weight 2, there are 26 linearly independent modular forms, organised into a triplet, a septet and two octets of Γ7. A full list of modular forms up to weight 8 are provided. Assuming the absence of flavons, the simplest modular-invariant models based on Γ7 are constructed, in which neutrinos gain masses via either the Weinberg operator or the type-I seesaw mechanism, and their predictions compared to experiment.

John Horsley

1932 ◽  
Vol 22 (2) ◽  
pp. 161-164
Author(s):  
George Macdonald
Keyword(s):  
Great Book ◽  
Early Age ◽  
Present Purpose ◽  
First Time

On January 12th, 1732, John Horsley, Presbyterian divine and schoolmaster, died suddenly at Morpeth at the early age of 46. The following March or April witnessed the publication of his great book, in which real scholarship was for the first time brought to bear upon the interpretation of Romano-British antiquities. The occurrence of this double bicentenary seems to provide an appropriate opportunity for reminding readers of the Journal of the magnitude of the achievement represented by the Britannia Romana. A fully documented account of the author's career, together with an estimate of the value of his work, will appear in the forthcoming volume of Archaeologia Aeliana. For the present purpose, therefore, a brief summary will suffice.

Pregnancy and the Risk of Rheumatoid Arthritis in a Highly Predisposed North American Native Population

2012 ◽  
Vol 39 (12) ◽  
pp. 2253-2260 ◽  
Author(s):  
CHRISTINE A. PESCHKEN ◽  
DAVID B. ROBINSON ◽  
CAROL A. HITCHON ◽  
IRENE SMOLIK ◽  
DONNA HART ◽  
...  
Keyword(s):  
Rheumatoid Arthritis ◽  
North American ◽  
Shared Epitope ◽  
Reproductive History ◽  
Early Age ◽  
Age At First Birth ◽  
Native Population ◽  
First Birth ◽  
Pregnancy Smoking ◽  
First Time

Objective.To examine reproductive history and rheumatoid arthritis (RA) risk in a highly predisposed population of North American Natives (NAN) with unique fertility characteristics.Methods.The effect of pregnancy on the risk of RA was examined by comparing women enrolled in 2 studies: a study of RA in NAN patients and their unaffected relatives; and NAN patients with RA and unrelated healthy NAN controls enrolled in a study of autoimmunity. All participants completed questionnaires detailing their reproductive history.Results.Patients with RA (n = 168) and controls (n = 400) were similar overall in age, education, shared epitope frequency, number of pregnancies, age at first pregnancy, smoking, and breastfeeding history. In multivariate analysis, for women who had ≥ 6 births the OR for developing RA was 0.43 (95% CI 0.21–0.87) compared with women who had 1–2 births (p = 0.046); for women who gave birth for the first time after age 20 the OR for developing RA was 0.33 (95% CI 0.16–0.66) compared with women whose first birth occurred at age ≤ 17 (p = 0.001). The highest risk of developing RA was in the first postpartum year (OR 3.8; 95% CI 1.45–9.93) compared with subsequent years (p = 0.004).Conclusion.In this unique population, greater parity significantly reduced the odds of RA; an early age at first birth increased the odds, and the postpartum period was confirmed as high risk for RA onset. The protective effect of repeated exposure to the ameliorating hormonal and immunological changes of pregnancy may counterbalance the effect of early exposure to the postpartum reversal of these changes.

Enzootic Activity of Chlamydia in Farms Located in a Hotspot Area for Zoonosis Emergence

2021 ◽  
Author(s):  
Ezequiel Andres Vanderhoeven ◽  
Jessica P. Mosmann ◽  
Adrián Díaz ◽  
Cecilia G. Cuffini
Keyword(s):  
Bird Species ◽  
Farm Animals ◽  
Economic Losses ◽  
Wild Mammals ◽  
Specific Pcr ◽  
Chlamydial Species ◽  
Zoonotic Risk ◽  
Two Samples ◽  
In The Wild ◽  
First Time

Abstract Chlamydias are obligated intracellular Gram-negative bacteria, considered important zoonotic pathogens, broadly present in several bird species and responsible for economic losses in animal production. We analyzed the presence of Chlamydial species with zoonotic risk in farm animals in a highly biodiverse area and with great human circulation, the Argentine, Brazil and Paraguay tri-border area. We surveyed nine farms in an area and nasally swabbed a total of 62 animals. DNA was extracted and specific PCR was performed to identify chlamydial species. We detected Chlamydia spp . in 6.5% (4/62) of the animals tested, positive samples belonged to cattle and none of them showed symptoms of respiratory disease nor had been diagnose with reproductive diseases. Specific nested PCR confirmed two samples belonged to C. pecorum and two to C. psittaci . We report for the first time Chlamydia circulation with zoonotic risk in the region. Surveys in birds and wild mammals could give a better understanding to know what Chlamydial species are circulating in the wild interface. The zoonotic potential should be taking into account as farm workers and the surrounding population could be silent carriers or have respiratory diseases being underdiagnosed, and therefore should be considered in the differential diagnoses.

An ecological explanation for hyperallometric scaling of reproduction

2021 ◽  
Author(s):  
Tomos Potter ◽  
Anja Felmy
Keyword(s):  
Body Size ◽  
Reproductive Output ◽  
Resource Competition ◽  
Natural Populations ◽  
Scaling Exponent ◽  
Wild Populations ◽  
Wet Season ◽  
Size Dependent ◽  
In The Wild ◽  
The Relationship

AbstractIn wild populations, large individuals have disproportionately higher reproductive output than smaller individuals. We suggest an ecological explanation for this observation: asymmetry within populations in rates of resource assimilation, where greater assimilation causes both increased reproduction and body size. We assessed how the relationship between size and reproduction differs between wild and lab-reared Trinidadian guppies. We show that (i) reproduction increased disproportionately with body size in the wild but not in the lab, where effects of resource competition were eliminated; (ii) in the wild, the scaling exponent was greatest during the wet season, when resource competition is strongest; and (iii) detection of hyperallometric scaling of reproduction is inevitable if individual differences in assimilation are ignored. We propose that variation among individuals in assimilation – caused by size-dependent resource competition, niche expansion, and chance – can explain patterns of hyperallometric scaling of reproduction in natural populations.

Comparative Analysis of the Proteomic Profile of Cattle Hides that Produce Loose and Tight Leather using In-Gel Tryptic Digestion followed by LC-MS/MS

2020 ◽  
Vol 115 (11) ◽  
pp. 399-408
Author(s):  
Catherine Maidment ◽  
Meekyung Ahn ◽  
Rafea Naffa ◽  
Trevor Loo ◽  
Gillian Norris
Keyword(s):  
Type I Collagen ◽  
Raw Material ◽  
Type I ◽  
Collagen Structure ◽  
Proteomic Profile ◽  
Collagen Network ◽  
Collagen Concentration ◽  
Different Types ◽  
Molecular Components ◽  
First Time

Looseness is a defect found in leather that reduces its quality by causing a wrinkly appearance in the finished product, resulting in a reduction in its value. Earlier studies on loose leather using microscopy and Raman spectroscopy reported a change in the collagen structure of loose leather. In this study, proteomics was used to investigate the possible molecular causes of looseness in the raw material, the first time such a study has been carried out. Proteins extracted from two regions of raw hide using two different methods were analysed; those taken from the distal axilla, an area prone to looseness, and those taken from the backbone which is less prone to looseness. Analyses using 1DE-LC-MS/MS showed that although the overall collagen concentration was similar in both areas of the hide, the distribution of the different types of collagen differed.  Specifically, concentrations of type I collagen, and the collagen-associated proteoglycan decorin were lower in samples taken from the distal axilla, symptomatic of a collagen network with excess space seen for these samples using confocal microscopy. This study suggests a possible link between the molecular components of raw cattle hide and looseness and more importantly between the molecular components of skin and skin defects. There is therefore potential to develop biomarkers for looseness which will enable early preventative action.

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