scholarly journals Reconstructing the ecology of a Jurassic pseudoplanktonic raft colony

2020 ◽  
Vol 7 (7) ◽  
pp. 200142
Author(s):  
Aaron W. Hunter ◽  
David Casenove ◽  
Celia Mayers ◽  
Emily G. Mitchell
Keyword(s):  
Spatial Analysis ◽  
Life Expectancy ◽  
Moisture Diffusion ◽  
Oceanic Islands ◽  
Diffusion Models ◽  
Spatial Point ◽  
Floating System ◽  
Mode Of Life ◽  
Ecosystem Collapse

Pseudoplanktonic crinoid raft colonies are an enigma of the Jurassic. These raft colonies are thought to have developed as floating filter-feeding communities due to an exceptionally rich oceanic niche, high in the water column enabling them to reach large densities on these log rafts. However, this pseudoplanktonic hypothesis has not been quantitatively tested, and there remains some doubt that this mode of life was possible. The ecological structure of the crinoid colony is resolved using spatial point process analyses and the duration estimates of the floating system until sinking using moisture diffusion models. Using spatial analysis, we found that the crinoids would have trailed preferentially positioned at the back of the floating log in the regions of least resistance, consistent with a floating, not benthic ecology. Additionally, we found using a series of moisture diffusion models at different log densities and sizes that ecosystem collapse did not take place solely due to colonies becoming overladen as previously assumed. Our analyses have found that these crinoid colonies studied could have existed for more than 10 years, even up to 20 years, exceeding the life expectancy of modern documented raft systems with possible implications for the role of modern raft communities in the biotic colonization of oceanic islands and intercontinental dispersal of marine and terrestrial species.

scholarly journals Reconstructing the ecology of a Jurassic pseudoplanktonic megaraft colony

2019 ◽  
Author(s):  
Aaron W. Hunter ◽  
David Casenove ◽  
Emily G. Mitchell ◽  
Celia Mayers
Keyword(s):  
Moisture Diffusion ◽  
Oceanic Islands ◽  
Diffusion Models ◽  
Deep Time ◽  
Cast Doubt ◽  
Commercial Logging ◽  
Mode Of Life ◽  
First Time

AbstractPseudoplanktonic crinoid megaraft colonies are an enigma of the Jurassic. They are among the largest in-situ invertebrate accumulations ever to exist in the Phanerozoic fossil record. These megaraft colonies and are thought to have developed as floating filter-feeding communities due to an exceptionally rich relatively predator free oceanic niche, high in the water column enabling them to reach high densities on these log rafts. However, this pseudoplanktonic hypothesis has never actually been quantitatively tested and some researchers have cast doubt that this mode of life was even possible. The ecological structure of the crinoid colony is resolved using spatial point process techniques and its longevity using moisture diffusion models. Using spatial analysis we found that the crinoids would have trailed preferentially positioned at the back of migrating structures in the regions of least resistance, consistent with a floating, not benthic ecology. Additionally, we found using a series of moisture diffusion models at different log densities and sizes that ecosystem collapse did not take place solely due to colonies becoming overladen as previously assumed. We have found that these crinoid colonies studied could have existed for greater than 10 years, even up to 20 years exceeding the life expectancy of modern documented megaraft systems with implications for the role of modern raft communities in the biotic colonisation of oceanic islands and intercontinental dispersal of marine and terrestrial species.Significance statementTransoceanic rafting is the principle mechanism for the biotic colonisation of oceanic island ecosystems. However, no historic records exist of how long such biotic systems lasted. Here, we use a deep-time example from the Early Jurassic to test the viability of these pseudoplanktonic systems, resolving for the first time whether these systems were truly free floating planktonic and viable for long enough to allow its inhabitants to grow to maturity. Using spatial methods we show that these colonies have a comparable structure to modern marine pesudoplankton on maritime structures, whilst the application of methods normally used in commercial logging is used to demonstrate the viability of the system which was capable of lasting up to 20 years.

Endokrinológiai tényezők és metabolikus folyamatok szerepe az élettartam szabályozásában

2021 ◽  
Vol 162 (33) ◽  
pp. 1318-1327
Author(s):  
Tamás Halmos ◽  
Ilona Suba
Keyword(s):  
Insulin Resistance ◽  
Metabolic Syndrome ◽  
Life Expectancy ◽  
Significant Risk ◽  
Low Grade ◽  
Aging Effects ◽  
Protective Function ◽  
Beneficial Effects ◽  
Age Related

Összefoglaló. Az emberek a lehető leghosszabb ideig akarnak élni, jó egészségben. Ha kiküszöbölnénk a kedvezőtlen külső körülményeket, a várható élettartam meghaladhatná a 100 évet. A 20. és 21. században a jóléti társadalmakban a várható élettartam jelentősen megnőtt, így Magyarországon is. Az áttekintett irodalom alapján megvizsgáltuk, hogy a genetika és az öröklődés mellett milyen endokrinológiai és metabolikus tényezők játszanak szerepet az élet meghosszabbításában. Megvizsgáltunk minden endogén tényezőt, amely pozitívan vagy negatívan befolyásolhatja az életkorral összefüggő betegségeket (Alzheimer-kór, szív- és érrendszeri betegségek, rák) és az élettartamot. Kiemeltük a hyperinsulinaemia, az inzulinrezisztencia, a metabolikus szindróma öregedést gyorsító hatását, az inzulinszerű növekedési hormon-1 ellentmondásos szerepét, valamint az élet meghosszabbításában részt vevő, újabban felfedezett peptideket, mint a klotho és a humanin. Ismertettük a mitochondriumok szerepét az élettartam meghatározásában, bemutattuk a mitohormesis folyamatát és annak stresszvédő funkcióját. Bemutattuk a rapamicin célszervét, az mTOR-t, amelynek gátlása meghosszabbítja az élettartamot, valamint a szirtuinokat. Kitértünk az autophagia folyamatára, és ismertettük a szenolitikumok szerepét az öregedésben. Az időskori autoimmunitás csökkenése hozzájárul az élettartam rövidüléséhez, utaltunk a thymus koordináló szerepére. Kiemeltük a bélmikrobiom fontos szerepét az élettartam szabályozásában. Hivatkoztunk a „centenáriusok” megfigyeléséből nyert humánadatokra. Megvizsgáltuk, milyen beavatkozási lehetőségek állnak rendelkezésre az egészségben tölthető élettartam meghosszabbításához. Az életmódbeli lehetőségek közül kiemeltük a kalóriabevitel-csökkentés és a testmozgás jótékony szerepét. Megvizsgáltuk egyes gyógyszerek feltételezett hatásait. Ezek közé tartozik a metformin, az akarbóz, a rezveratrol. E gyógyszerek mindegyikének hatása hasonló a kalóriamegszorításéhoz. Nincs olyan „csodaszer”, amely igazoltan meghosszabbítja az élettartamot emberben. Egyes géneknek és génmutációknak jótékony hatásuk van, de ezt környezeti tényezők, betegségek, balesetek és más külső ártalmak módosíthatják. Kiemeljük az elhízás, az alacsony fokozatú gyulladás és az inzulinrezisztencia öregedésre gyakorolt gyorsító hatását. A metabolikus szindróma elterjedtsége miatt ez jelentős népegészségügyi kockázatot jelent. Az inzulin, a növekedési hormon és az inzulinszerű növekedési faktorok hatásainak értékelése továbbra is ellentmondásos. Az egészséges, szellemileg és fizikailag aktív életmód, a kalóriacsökkentés mindenképpen előnyös. Az életet meghosszabbító szerek értékelése még vitatott. Orv Hetil. 2021; 162(33): 1318–1327. Summary. People want to live as long as possible in good health. If we eliminate the unfavorable external conditions, the life expectancy could exceed 100 years. In the 20th and 21th centuries, life expectancy in welfare societies increased significantly, including in Hungary. Based on the reviewed literature, we examined what endocrinological and metabolic factors play a role in prolonging life in addition to genetics and inheritance. We examined all endogenous factors that can positively or negatively affect age-related diseases (Alzheimer’s disease, cardiovascular disease, cancer) and longevity. We highlighted the aging effects of hyperinsulinemia, insulin resistance, metabolic syndrome, the controversial role of insulin-like growth factor-1, and more recently discovered peptides involved in prolonging lifespan, such as klotho and humanin. We described the role of mitochondria in determining longevity, we demonstrated the process of mitohormesis and its stress-protective function. We presented the target organ of rapamycin, mTOR, the inhibition of which prolongs lifespan, as well as sirtuins. We covered the process of autophagy and described the role of senolytics in aging. The decrease in autoimmunity in old age contributes to the shortening of life expectancy, we referred to the coordinating role of the thymus. We highlighted the important role of intestinal microbiome in the regulation of longevity. We referred to human data obtained from observations on “centenarians”. We examined what intervention options are available to prolong healthy life expectancy. Among the lifestyle options, we highlighted the beneficial role of calorie reduction and exercise. We examined the putative beneficial effects of some drugs. These include metformin, acarbose, resveratrol. The effect of each of these drugs is similar to calorie restriction. There is no “miracle cure” that has been shown to prolong life-span in humans. Some genes and gene mutations have beneficial effects, but this can be modified by environmental factors, diseases, accidents, and other external harms. We highlight the accelerating effects of obesity, low-grade inflammation, and insulin resistance on aging. Due to the prevalence of metabolic syndrome, this poses a significant risk to public health. The assessment of the effects of insulin, growth hormone, and insulin-like growth factors remains controversial. A healthy, mentally and physically active lifestyle, calorie reduction is definitely beneficial. The evaluation of life-prolonging agents is still controversial. Orv Hetil. 2021; 162(33): 1318–1327.

scholarly journals Sails at the water: ecological convergence between sphenacodontids and spinosaurids?

2017 ◽  
Author(s):  
Dawid Mazurek
Keyword(s):  
Mode Of Life ◽  
Thermoregulatory Function ◽  
Ecological Convergence

Spinosaurids (Diapsida: Spinosauridae) and sphenacodontids (Synapsida: Sphenacodontidae) share not only a characteristic tall neural spines, but also an atypical – compared to their close respective relatives – ecology, i.e. apparently piscivorous and possibly semiaquatic mode of life. This similarity might hold clue for the role of their sails. It is here suggested that sails of these animals 1) served thermoregulatory function, warming the animals, otherwise submerged in the water, as well as 2) enabled them to hunt for fish in a way similar to the technique of Recent diapsid, black heron (Egretta ardesiaca).

scholarly journals Neuropsychological rehabilitation of memory in post-stroke patients with brain nonspecific structure injury

2021 ◽  
Vol 101 ◽  
pp. 03023
Author(s):  
Tatiana Aleksandrovna Mardasova ◽  
Pavel Rafaelevich Iusupov
Keyword(s):  
Life Expectancy ◽  
Management System ◽  
Social Activity ◽  
Stroke Patients ◽  
Neuropsychological Rehabilitation ◽  
Memory Impairments ◽  
Post Stroke

The relevance of the study of the neuropsychological rehabilitation of memory impairments in stroke and the increasing role of the development of the rehabilitation direction to build a competent management system for such patients suggests good conditions for improving the health of the population, increasing the life expectancy and social activity of people.

scholarly journals Relationship between life of mate butterflies and leading selection characteristics

2021 ◽  
Vol 244 ◽  
pp. 02028
Author(s):  
U. Khudayberdieva ◽  
S. Navruzov ◽  
N. Rajabov ◽  
O. Karimov ◽  
K.H. Fozilova
Keyword(s):  
Life Expectancy ◽  
National Economy ◽  
Economic Value ◽  
Breeding Work ◽  
Coefficient Of Variability ◽  
History Of ◽  
The Republic ◽  
Selection Work ◽  
Research Institute

This article examines the history of silkworm breeding, the role of silkworm breeding in the national economy of the Republic of Uzbekistan and the role of silkworm breeding in the development of the industry. This is because the interrelationship of traits of economic value is of great importance in selection and breeding work. The experiments were conducted in 2015-2017 at the Silk Research Institute of Uzbekistan. The life expectancy of the experimental butterflies was 10.9-12.8 days and the variability was 33.9-56.6%. The coefficient of variability indicates the degree of diversity in the population on this trait. Thus, it is clear from the results that the population of “Marvarid” and “Liniya 27” has the ability to carry out selection work on the sign of life expectancy of female butterflies.

scholarly journals INTERNATIONAL EXPERIENCE OF PUBLIC ADMINISTRATION OF PRODUCTION AND TURNOVER OF MEDICINES IN UKRAINE

2020 ◽  
pp. 151-159
Author(s):  
Л. В. Котенко
Keyword(s):  
Health Care ◽  
Life Expectancy ◽  
Public Administration ◽  
International Cooperation ◽  
International Organizations ◽  
Good Manufacturing Practice ◽  
International Experience ◽  
Iso 9001 ◽  
Regulatory Bodies

The article forms the international experience of public administration of production and circulation of medicines in Ukraine. The role of international organizations in maintaining the health of the nation, increasing the level of labor productivity, as well as the quality and life expectancy of people is studied. The leaders of the European market of drug manufacturers have been identified. The international standard ISO 9001 and features of introduction of good manufacturing practice (GMP) are analyzed. The international cooperation for the regulatory bodies of the WHO member states is described in order to discuss ways to strengthen cooperation in the field of health care.

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