Normalized lifespan inequality: disentangling the longevity–lifespan variability nexus

Previous studies have documented a historically strong and negative association between countries’ life expectancy (i.e., average longevity) and length-of-life inequality (i.e., variability in ages at death). The relationship between both variables might be partially explained by life expectancy increasing at a faster pace than maximal length of life, a phenomenon that mechanically compresses the age-at-death distribution and has not been taken into consideration in previous studies. In this paper, we propose a new approach to lifespan inequality measurement that accounts for the (uncertainly) bounded nature of length-of-life. Applying the new approach to the countries of the Human Mortality Database, we observe that the decline in overall lifespan variability typically associated with increases in longevity seems to stop and even reverse at higher levels of life expectancy. This suggests the emergence of worrying ethical dilemmas, whereby higher achievements in longevity would only be possible at the expense of higher lifespan variability.

CHARACTERISTICS AND FEATURES OF GROWTH PROCESSES OF WOODY PLANTS IN ARID REGIONS

The aim of the study is to study the features of the growth processes of woody plants in an arid region to determine the prospects of their use in protective afforestation of sparsely wooded regions. The objects of research are trees and shrubs of bioresource collections of the Federal Scientific Centre of Agroecology, Complex Melioration and Protective Afforestation of the Russian Academy of Sciences. The structure of dendrological collections was revealed according to the growth forms of woody plants (6 groups: 1 - trees; 2 - medium shrubs, 3 - tall, 4 - tall shrubs with thorns, 5 - medium ones with thorns, 6 - low). It has been established that active growth processes take place in a favorable spring season (April) with moisture in the soil (up to 15 ... 17% to absolutely dry mass) and average daily air temperatures - + 15.1 ... 17,6 ºC. The groups of woody plants were distinguished according to the duration and intensity of growth processes: I - with short and intense monocyclic shoot growth (25 ... 37 days; Quercus, Acer, Tilia, Crataegus, Sorbus, Fraxinus, Amygdalus nana) and II - with a long period (40 ... 63 days; Betula, Gleditsia, Robinia, Juglans, Catalpa, Sumbucus, Cotoneaster). The ranking of shrubs by 4 classes of growth was carried out using the example of the Rosaceae family. With sufficient moisture in a dry steppe, growth processes occur intensively at the age of up to 10 ... 15 years. The average longevity of tree species in artificial plantations of the region is 40 ... 50 years, in chestnut soils, and its subtypes - 30 ... 40, with additional moisture increases to 60 ... 70 years (Fraxinus excelsior, Quercus robur, Pinus sylvestris, Acer platanoides)

Diet-dependent entropic assessment of athletes’ lifespan

Life expectancies of the athletes depend on the sports they are doing. The entropic age concept, which was found successful in the previous nutrition studies, will be employed to assess the relation between the athletes’ longevity and nutrition. Depending on their caloric needs, diets are designed for each group of athletes based on the most recent guidelines while they are pursuing their careers and for the post-retirement period, and then the metabolic entropy generation was worked out for each group. Their expected lifespans, based on attaining the lifespan entropy limit, were calculated. Thermodynamic assessment appeared to be in agreement with the observations. There may be a significant improvement in the athletes’ longevity if they shift to a retirement diet after the age of 50. The expected average longevity for male athletes was 56 years for cyclists, 66 years for weightlifters, 75 years for rugby players and 92 years for golfers. If they should start consuming the retirement diet after 50 years of age, the longevity of the cyclists may increase for 7 years, and those of weightlifters, rugby players and golfers may increase for 22, 30 and 8 years, respectively.

Demography of galactic technosignatures

ABSTRACT Probabilistic arguments about the existence of technological life beyond Earth traditionally refer to the Drake equation to draw possible estimates of the number of technologically advanced civilizations releasing, either intentionally or not, electromagnetic emissions in the Milky Way. Here, we introduce other indicators than Drake’s number ND to develop a demography of artificial emissions populating the Galaxy. We focus on three main categories of statistically independent signals (isotropic, narrow beams, and rotating beacons) to calculate the average number NG of emission processes present in the Galaxy and the average number of them crossing Earth, $\bar{k}$, which is a quantity amenable to statistical estimation from direct observations. We show that $\bar{k}$ coincides with ND only for isotropic emissions, while $\bar{k}$ can be orders of magnitude smaller than ND in the case of highly directional signals. We further show that while ND gives the number of emissions being released at the present time, NG considers also the signals from no longer active emitters but whose emissions still occupy the Galaxy. We find that as long as the average longevity of the emissions is shorter than about 105 yr, NG is fully determined by the rate of emissions alone, in contrast to ND and $\bar{k}$ which depend also on the emission longevity. Finally, using analytic formulas of NG, ND, and $\bar{k}$ determined for each type of emission processes here considered, we provide a comprehensive overview of the values these quantities can possibly achieve as functions of the emission birthrates, longevities, and directionality.

Relationship Between Age at First Calving and Longevity and Productive Life in Holstein Cows

The aim of the study was to evaluate the effect of age at first calving on functional traits – longevity and productive life in dairy cows. The survey included 1490 Holstein cows from 5 cattle farms in Bulgaria. The average milk yield per cow in the farms studied ranged from 6031.68 kg to 8660.37 kg. The average age at first calving was 29.68 months. The highest percentage of cows calved for the first time at age 28–30 months – 29.53%, generally 38.06% of cows calved for the first time at a very high age – over 31 months and only 7.58% calved aged up to 24 months. The average longevity for all culled cows was 6.05 years and the productive life – 3.63 years. 22% of all culled cows at these farms were culled before the end of their first lactation. The highest total longevity was in cows calved for the first time at high age – over 28 months. Cows calved for the first time, both at low age (up to 24 months) and at high age (over 37 months), had a shorter productive life of 4.0 and 3.9 years, respectively. Cows with the shortest productive life – one year and less – had and the highest average age at first calving of 30.21 months.

The impact of nutritional quality and gut bacteria on the fitness of Bactrocera minax (Diptera: Tephritidae)

To examine how nutritional quality and resident gut bacteria interplay in improving the fitness of an oligophagous fruit fly, Bactrocera minax , artificial sucrose diets and full diets (sucrose, tryptone and yeast extract) were fed to flies with and without antibiotic supplementation. Furthermore, Klebsiella oxytoca and Citrobacter freundii were supplemented to sucrose-only diets. Flies were maintained in the laboratory and the fitness parameters, male and female longevity, number of copulations and female fecundity, were recorded. Full diet without bacterial depletion significantly increased fecundity and copulation. In the absence of gut bacteria, flies fed with full diets had significantly decreased mean fecundity and copulation rate. Flies that were fed with sucrose diet had a very low copulation rate and produced no eggs. Diet type and the presence of bacteria did not have any effect on the average longevity of male and female flies. Bacterial supplementation in sucrose diets did not improve any of the measured parameters. The results demonstrate that gut bacteria interact with diet to influence mating and reproduction in B. minax . Symbiotic bacteria significantly and positively impact reproduction in B. minax ; however, their impact can only be fully realized when the flies are fed with a nutritionally complete diet.

Survival and weak chaos

Survival analysis in biology and reliability theory in engineering concern the dynamical functioning of bio/electro/mechanical units. Here we incorporate effects of chaotic dynamics into the classical theory. Dynamical systems theory now distinguishes strong and weak chaos. Strong chaos generates Type II survivorship curves entirely as a result of the internal operation of the system, without any age-independent, external, random forces of mortality. Weak chaos exhibits (a) intermittency and (b) Type III survivorship, defined as a decreasingper capitamortality rate: engineering explicitly defines this pattern of decreasing hazard as ‘infant mortality’. Weak chaos generates two phenomena from the normal functioning of thesamesystem. First, infant mortality—sensuengineering—without any external explanatory factors, such as manufacturing defects, which is followed by increased average longevity of survivors. Second, sudden failure of units during their normal period of operation, before the onset of age-dependent mortality arising from senescence. The relevance of these phenomena encompasses, for example: no-fault-found failure of electronic devices; high rates of human early spontaneous miscarriage/abortion; runaway pacemakers; sudden cardiac death in young adults; bipolar disorder; and epilepsy.

LIFE-SPAN COWS OF UKRAINIAN BLACK-AND-WHITE DAIRY BREED IS DEPENDING ON LEVEL ESTIMATION OF LINEAR TYPE TRAITS WHICH CHARACTERIZE THE CONDITION OF FEET AND LEGS

Research on assessing the type of first-calf heifers of Sumy interbreed type of Ukrainian Black-and-White dairy cattle was conducted by the method of linear classification in a herd of breeding farm Pidlisnivska branch of private stock company "Rise-Maksymko", Sumy region. The descriptive traits of type characterizing condition of cow’s limbs: hock angle, rear legs rear view, hoof angle and locomotion were studied. According to the research results, hock angle affects greatly longevity of the studied cows in the herd. The longest duration of life had the animals estimated in 6 and 5 points by the trait of hock angle. The difference in longevity between the cows estimated in 6 points compared with the groups of animals with assessment of 1 and 9 points, was 252 and 582 days respectively. Animals with elephantine rear legs rear view was used by 330 days longer, compared with the animals of same age with sickle hocks. The results proved a positive effect of rear legs rear view on longevity of the animals. The difference between the animal groups with the highest and lowest scores was 735 days with high degree of reliability (P<0.001). The high influence the trait of hoof angle on longevity of cows was determined. Animals with the highest classification score lived 626 days longer than animals with a score of one point. However, it should be noted that hoof angle had the least impact on longevity among all traits which characterize qualitative condition of hind limbs. The cows with the assessment the trait of locomotion in 9 points lived 737 days longer compared with the animals with a score of one point. In general, assessing the average longevity of the cows of Sumy interbreed type of Ukrainian Black-and-White dairy breed depending on the level of assessment for the trait of locomotion it was established the most durable cows were with a score above 5 points. Studying the relationship between linear estimation of traits which characterize condition of feet and legs at the cows of Sumy interbreed type of Ukrainian Black-and-White dairy breed and their longevity it was found that the cows with high scores for condition of development of these traits would have longer productive use. Therefore, degree of development of the indicators of linear estimation of limbs for their daughters should take into account selecting sires to the herd.

Dietary restriction increases variability in longevity

Nutritional environments, particularly those experienced during early life, are hypothesized to affect longevity. A recent cross-taxa meta-analysis found that, depending upon circumstance, average longevity may be increased or decreased by early-life dietary restriction. Unstudied are the effects of diet during development on among-individual variance in longevity. Here, we address this issue using emerging methods for meta-analysis of variance. We found that, in general, standard deviation (s.d.) in longevity is around 8% higher under early-life dietary restriction than a standard diet. The effects became especially profound when dietary insults were experienced prenatally (s.d. increased by 29%) and/or extended into adulthood (s.d. increased by 36.6%). Early-life dietary restriction may generate variance in longevity as a result of increased variance in resource acquisition or allocation, but the mechanisms underlying these largely overlooked patterns clearly warrant elucidation.

Feeding Propensity and Cannibalism of Micraspis Discolor (Fab.) to Different Prey Species (Aphis craccivora and Nilaparbata lugens) under Laboratory

Feeding propensity and cannibalism of Micraspis discolor (Fab.) to different prey species (bean aphids and brown plant hopper ) was studied in the laboratory of the Department of Entomology, Bangladesh Agricultural University, Mymensingh, during January, 2007 to April, 2007. It was found that the highest pre-oviposition period was to 5.6±0.54 days when BPH were used and this period was lowest, 4.6±0.54 days using bean aphid. The oviposition period was maximum 40.20±1.78 days using bean aphid and minimum 29.00± 2.00 days were found using BPH. Maximum number of eggs 216.00±16.58 was laid when fed on bean aphid. The hatching percent was highest 88.71% using bean aphid and hatching percent was lowest 85.34% when fed on BPH. Incubation period varied from 2.40±0.54 to 3.80±0.44 days using different foods. However, the larvae passed through four larval instars and highest larval period was 10.00 ± 0.70 when BPH were used as food and lowest was 8.40 days feeding on bean aphid. Pupal period was 3.00±0.00 & 3.80±0.44 days when bean aphid & BPH were supplied as food. The average longevity of female was 38.60±3.78 and 31.40±2.96 days and that of male was 32.00±2.91 & 26.00±0.91 days when feeding on bean aphid and BPH respectively. It was significant at 1% level. The sex ratio of male and female was found (0.78:1.00) using different foods and these were not significant at 1% level. By this experiment, It was observed that feeding propensity of Micraspis discolor to different prey species during the total life cycle was as follows: bean aphid > BPH. It was also found that M. discolor had cannibalistic behavior and this was significant at 1% level.J. Environ. Sci. & Natural Resources, 9(1): 81-85 2016