Journal articles on the topic 'Disposable soma theory'
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1
Kirkwood, T. B. L. "The Disposable Soma Theory: Evidence and Implications." Netherlands Journal of Zoology 43, no. 3-4 (1992): 359–63. http://dx.doi.org/10.1163/156854293x00115.
2
Drenos, Fotios, and Thomas B. L. Kirkwood. "Modelling the disposable soma theory of ageing." Mechanisms of Ageing and Development 126, no. 1 (January 2005): 99–103. http://dx.doi.org/10.1016/j.mad.2004.09.026.
3
Douglas, Peter M., and Andrew Dillin. "The disposable soma theory of aging in reverse." Cell Research 24, no. 1 (November 5, 2013): 7–8. http://dx.doi.org/10.1038/cr.2013.148.
4
Abrams, Peter A., and Donald Ludwig. "Optimality Theory, Gompertz' Law, and the Disposable Soma Theory of Senescence." Evolution 49, no. 6 (December 1995): 1055. http://dx.doi.org/10.2307/2410431.
5
Abrams, Peter A., and Donald Ludwig. "OPTIMALITY THEORY, GOMPERTZ' LAW, AND THE DISPOSABLE SOMA THEORY OF SENESCENCE." Evolution 49, no. 6 (December 1995): 1055–66. http://dx.doi.org/10.1111/j.1558-5646.1995.tb04433.x.
6
Świątek, P., M. Vogelgesang, M. Romek, and J. Klag. "Germ-line versus somatic cells. I. Stereological study of differentiating embryonic tissues of Tetrodontophora bielanensis (Hexapoda, Collembola)." Canadian Journal of Zoology 82, no. 5 (May 1, 2004): 714–25. http://dx.doi.org/10.1139/z04-040.
Abstract:
We examined five different somatic tissues and compared them with germ-line cells to verify the "disposable soma" theory. Two embryonic stages and second-stage juveniles of Tetrodontophora bielanensis Waga, 1842 (Hexapoda, Collembola) were studied. Our results show that changes in relative volume of mitochondria during differentiation of cells correlate well with transformations of cell morphology. During morphological transformation of differentiating somatic cells, the relative volume of mitochondria in their cytoplasm is high, whereas in the differentiated tissues, this parameter is much lower. Surprisingly, the highest value of relative volume density of mitochondria is found in the cytoplasm of germ-line cells. If we accept that this parameter indicates the cell metabolism rate, then our results should be taken as supporting the "disposable soma" theory. It is also conceivable that the higher volume of mitochondria in the germ-line cells have nothing to do with energy production but, for instance, with the production or function of nuage material (germ-cell determinant) in the germ-line cells. These two possibilities are discussed.
7
da Silva, Jack. "Plastic Senescence in the Honey Bee and the Disposable Soma Theory." American Naturalist 194, no. 3 (September 2019): 367–80. http://dx.doi.org/10.1086/704220.
8
van den Heuvel, Joost, Sinead English, and Tobias Uller. "Disposable Soma Theory and the Evolution of Maternal Effects on Ageing." PLOS ONE 11, no. 1 (January 11, 2016): e0145544. http://dx.doi.org/10.1371/journal.pone.0145544.
9
Chen, Hwei-yen, Cecile Jolly, Kasparas Bublys, Daniel Marcu, and Simone Immler. "Trade-off between somatic and germline repair in a vertebrate supports the expensive germ line hypothesis." Proceedings of the National Academy of Sciences 117, no. 16 (April 3, 2020): 8973–79. http://dx.doi.org/10.1073/pnas.1918205117.
Abstract:
The disposable soma theory is a central tenet of the biology of aging where germline immortality comes at the cost of an aging soma [T. B. L. Kirkwood, Nature 270, 301–304 (1977); T. B. L. Kirkwood, Proc. R. Soc. Lond. B Biol. Sci. 205, 531–546 (1979); T. B. L. Kirkwood, S. N. Austad, Nature 408, 233–238 (2000)]. Limited resources and a possible trade-off between the repair and maintenance of the germ cells and growth and maintenance of the soma may explain the deterioration of the soma over time. Here we show that germline removal allows accelerated somatic healing under stress. We tested “the expensive germ line” hypothesis by generating germline-free zebrafish Danio rerio and testing the effect of the presence and absence of the germ line on somatic repair under benign and stressful conditions. We exposed male fish to sublethal low-dose ionizing radiation, a genotoxic stress affecting the soma and the germ line, and tested how fast the soma recovered following partial fin ablation. We found that somatic recovery from ablation occurred substantially faster in irradiated germline-free fish than in the control germline-carrying fish where somatic recovery was stunned. The germ line did show signs of postirradiation recovery in germline-carrying fish in several traits related to offspring number and fitness. These results support the theoretical conjecture that germline maintenance is costly and directly trades off with somatic maintenance.
10
Teulière, Jérôme, Debashish Bhattacharya, and Eric Bapteste. "Ancestral germen/soma distinction in microbes: Expanding the disposable soma theory of aging to all unicellular lineages." Ageing Research Reviews 60 (July 2020): 101064. http://dx.doi.org/10.1016/j.arr.2020.101064.
11
Sayer, Avan Aihie, and Cyrus Cooper. "Aging, sarcopenia and the life-course." Reviews in Clinical Gerontology 16, no. 4 (November 2006): 265–74. http://dx.doi.org/10.1017/s0959259807002225.
Abstract:
There is growing support for characterizing human aging from a life-course perspective, in terms of recognizing important influences operating from conception to death, and this approach provides a framework for understanding aging processes operating at the individual level. Kirkwood's disposable soma theory proposes that aging is a manifestation of imperfect somatic maintenance and repair processes. We can therefore predict that differing exposure to the determinants of somatic damage across the life-course, and variable capacity to respond in terms of repair are likely to underlie the wide variation in rates of aging between individuals.
12
Lorenzini, Antonello, Thomas Stamato, and Christian Sell. "The disposable soma theory revisited: Time as a resource in the theories of aging." Cell Cycle 10, no. 22 (November 15, 2011): 3853–56. http://dx.doi.org/10.4161/cc.10.22.18302.
13
Elsner, Daniel, Karen Meusemann, and Judith Korb. "Longevity and transposon defense, the case of termite reproductives." Proceedings of the National Academy of Sciences 115, no. 21 (May 7, 2018): 5504–9. http://dx.doi.org/10.1073/pnas.1804046115.
Abstract:
Social insects are promising new models in aging research. Within single colonies, longevity differences of several magnitudes exist that can be found elsewhere only between different species. Reproducing queens (and, in termites, also kings) can live for several decades, whereas sterile workers often have a lifespan of a few weeks only. We studied aging in the wild in a highly social insect, the termite Macrotermes bellicosus, which has one of the most pronounced longevity differences between reproductives and workers. We show that gene-expression patterns differed little between young and old reproductives, implying negligible aging. By contrast, old major workers had many genes up-regulated that are related to transposable elements (TEs), which can cause aging. Strikingly, genes from the PIWI-interacting RNA (piRNA) pathway, which are generally known to silence TEs in the germline of multicellular animals, were down-regulated only in old major workers but not in reproductives. Continued up-regulation of the piRNA defense commonly found in the germline of animals can explain the long life of termite reproductives, implying somatic cooption of germline defense during social evolution. This presents a striking germline/soma analogy as envisioned by the superorganism concept: the reproductives and workers of a colony reflect the germline and soma of multicellular animals, respectively. Our results provide support for the disposable soma theory of aging.
14
Blagosklonny, Mikhail V. "Why the disposable soma theory cannot explain why women live longer and why we age." Aging 2, no. 12 (December 29, 2010): 884–87. http://dx.doi.org/10.18632/aging.100253.
15
Blagosklonny, Mikhail V. "MTOR-driven quasi-programmed aging as a disposable soma theory: Blind watchmaker vs. intelligent designer." Cell Cycle 12, no. 12 (June 15, 2013): 1842–47. http://dx.doi.org/10.4161/cc.25062.
16
Lemaître, Jean-François, Jacob Moorad, Jean-Michel Gaillard, Alexei A. Maklakov, and Daniel H. Nussey. "A unified framework for evolutionary genetic and physiological theories of aging." PLOS Biology 22, no. 2 (February 27, 2024): e3002513. http://dx.doi.org/10.1371/journal.pbio.3002513.
Abstract:
Why and how we age are 2 intertwined questions that have fascinated scientists for many decades. However, attempts to answer these questions remain compartmentalized, preventing a comprehensive understanding of the aging process. We argue that the current lack of knowledge about the evolution of aging mechanisms is due to a lack of clarity regarding evolutionary theories of aging that explicitly involve physiological processes: the disposable soma theory (DST) and the developmental theory of aging (DTA). In this Essay, we propose a new hierarchical model linking genes to vital rates, enabling us to critically reevaluate the DST and DTA in terms of their relationship to evolutionary genetic theories of aging (mutation accumulation (MA) and antagonistic pleiotropy (AP)). We also demonstrate how these 2 theories can be incorporated in a unified hierarchical framework. The new framework will help to generate testable hypotheses of how the hallmarks of aging are shaped by natural selection.
17
Lansdorp, Peter M. "Telomeres, aging, and cancer: the big picture." Blood 139, no. 6 (February 10, 2022): 813–21. http://dx.doi.org/10.1182/blood.2021014299.
Abstract:
Abstract The role of telomeres in human health and disease is yet to be fully understood. The limitations of mouse models for the study of human telomere biology and difficulties in accurately measuring the length of telomere repeats in chromosomes and cells have diverted attention from many important and relevant observations. The goal of this perspective is to summarize some of these observations and to discuss the antagonistic role of telomere loss in aging and cancer in the context of developmental biology, cell turnover, and evolution. It is proposed that both damage to DNA and replicative loss of telomeric DNA contribute to aging in humans, with the differences in leukocyte telomere length between humans being linked to the risk of developing specific diseases. These ideas are captured in the Telomere Erosion in Disposable Soma theory of aging proposed herein.
18
Speakman, John R., and Elżbieta Król. "The Heat Dissipation Limit Theory and Evolution of Life Histories in Endotherms—Time to Dispose of the Disposable Soma Theory?" Integrative and Comparative Biology 50, no. 5 (May 21, 2010): 793–807. http://dx.doi.org/10.1093/icb/icq049.
19
Mitteldorf, Joshua. "CAN EXPERIMENTS ON CALORIC RESTRICTION BE RECONCILED WITH THE DISPOSABLE SOMA THEORY FOR THE EVOLUTION OF SENESCENCE?" Evolution 55, no. 9 (2001): 1902. http://dx.doi.org/10.1554/0014-3820(2001)055[1902:ceocrb]2.0.co;2.
20
Mitteldorf, Joshua. "CAN EXPERIMENTS ON CALORIC RESTRICTION BE RECONCILED WITH THE DISPOSABLE SOMA THEORY FOR THE EVOLUTION OF SENESCENCE?" Evolution 55, no. 9 (September 2001): 1902–5. http://dx.doi.org/10.1111/j.0014-3820.2001.tb00841.x.
21
Falandry, Claire, Marc Bonnefoy, Gilles Freyer, and Eric Gilson. "Biology of Cancer and Aging: A Complex Association With Cellular Senescence." Journal of Clinical Oncology 32, no. 24 (August 20, 2014): 2604–10. http://dx.doi.org/10.1200/jco.2014.55.1432.
Abstract:
Over the last 50 years, major improvements have been made in our understanding of the driving forces, both parallel and opposing, that lead to aging and cancer. Many theories on aging first proposed in the 1950s, including those associated with telomere biology, senescence, and adult stem-cell regulation, have since gained support from cumulative experimental evidence. These views suggest that the accumulation of mutations might be a common driver of both aging and cancer. Moreover, some tumor suppressor pathways lead to aging in line with the theory of antagonist pleiotropy. According to the evolutionary-selected disposable soma theory, aging should affect primarily somatic cells. At the cellular level, both intrinsic and extrinsic pathways regulate aging and senescence. However, increasing lines of evidence support the hypothesis that these driving forces might be regulated by evolutionary-conserved pathways that modulate energy balance. According to the hyperfunction theory, aging is a quasi-program favoring both age-related diseases and cancer that could be inhibited by the regulation of longevity pathways. This review summarizes these hypotheses, as well as the experimental data that have accumulated over the last 60 years linking aging and cancer.
22
Gavrilov, Leonid A., and Natalia S. Gavrilova. "Evolutionary Theories of Aging and Longevity." Scientific World JOURNAL 2 (2002): 339–56. http://dx.doi.org/10.1100/tsw.2002.96.
Abstract:
The purpose of this article is to provide students and researchers entering the field of aging studies with an introduction to the evolutionary theories of aging, as well as to orient them in the abundant modern scientific literature on evolutionary gerontology. The following three major evolutionary theories of aging are discussed: 1) the theory of programmed death suggested by August Weismann, 2) the mutation accumulation theory of aging suggested by Peter Medawar, and 3) the antagonistic pleiotropy theory of aging suggested by George Williams. We also discuss a special case of the antagonistic pleiotropy theory, the disposable soma theory developed by Tom Kirkwood and Robin Holliday. The theories are compared with each other as well as with recent experimental findings. At present the most viable evolutionary theories are the mutation accumulation theory and the antagonistic pleiotropy theory; these theories are not mutually exclusive, and they both may become a part of a future unifying theory of aging.Evolutionary theories of aging are useful because they open new oppor-tunities for further research by suggesting testable predictions, but they have also been harmful in the past when they were used to impose limitations on aging studies. At this time, the evolutionary theories of aging are not ultimate completed theories, but rather a set of ideas that themselves require further elaboration and validation. This theoretical review article is written for a wide readership.
23
Lemaître, Jean-François, Jean-Michel Gaillard, Josephine M. Pemberton, Tim H. Clutton-Brock, and Daniel H. Nussey. "Early life expenditure in sexual competition is associated with increased reproductive senescence in male red deer." Proceedings of the Royal Society B: Biological Sciences 281, no. 1792 (October 7, 2014): 20140792. http://dx.doi.org/10.1098/rspb.2014.0792.
Abstract:
The evolutionary theories of senescence predict that investment in reproduction in early life should come at the cost of reduced somatic maintenance, and thus earlier or more rapid senescence. There is now growing support for such trade-offs in wild vertebrates, but these exclusively come from females. Here, we test this prediction in male red deer ( Cervus elaphus ) using detailed longitudinal data collected over a 40-year field study. We show that males which had larger harems and thereby allocated more resources to reproduction during early adulthood experienced higher rates of senescence in both harem size and rut duration. Males that carried antlers with more points during early life did not show more pronounced declines in reproductive traits in later life. Overall, we demonstrate that sexual competition shapes male reproductive senescence in wild red deer populations and provide rare empirical support for the disposable soma theory of ageing in males of polygynous vertebrate species.
24
Lind, Martin I., Hanne Carlsson, Elizabeth M. L. Duxbury, Edward Ivimey-Cook, and Alexei A. Maklakov. "Cost-free lifespan extension via optimization of gene expression in adulthood aligns with the developmental theory of ageing." Proceedings of the Royal Society B: Biological Sciences 288, no. 1944 (February 3, 2021): 20201728. http://dx.doi.org/10.1098/rspb.2020.1728.
Abstract:
Ageing evolves because the force of selection on traits declines with age but the proximate causes of ageing are incompletely understood. The ‘disposable soma’ theory of ageing (DST) upholds that competitive resource allocation between reproduction and somatic maintenance underpins the evolution of ageing and lifespan. In contrast, the developmental theory of ageing (DTA) suggests that organismal senescence is caused by suboptimal gene expression in adulthood. While the DST predicts the trade-off between reproduction and lifespan, the DTA predicts that age-specific optimization of gene expression can increase lifespan without reproduction costs. Here we investigated the consequences for lifespan, reproduction, egg size and individual fitness of early-life, adulthood and post-reproductive onset of RNAi knockdown of five ‘longevity’ genes involved in key biological processes in Caenorhabditis elegans . Downregulation of these genes in adulthood and/or during post-reproductive period increases lifespan, while we found limited evidence for a link between impaired reproduction and extended lifespan. Our findings demonstrate that suboptimal gene expression in adulthood often contributes to reduced lifespan directly rather than through competitive resource allocation between reproduction and somatic maintenance. Therefore, age-specific optimization of gene expression in evolutionarily conserved signalling pathways that regulate organismal life histories can increase lifespan without fitness costs.
25
Chereji, E., M. Gatz, N. L. Pedersen, and C. A. Prescott. "Reexamining the Association Between Fertility and Longevity: Testing the Disposable Soma Theory in a Modern Human Sample of Twins." Journals of Gerontology Series A: Biological Sciences and Medical Sciences 68, no. 5 (December 4, 2012): 499–509. http://dx.doi.org/10.1093/gerona/gls218.
26
Chmielewski, Piotr Paweł. "Human ageing, longevity and evolution: can ageing be programmed?" Anthropological Review 82, no. 4 (December 1, 2019): 417–33. http://dx.doi.org/10.2478/anre-2019-0032.
Abstract:
Abstract Understanding the proximate and ultimate causes of ageing is one of the key challenges in current biology and medicine. These problems are so important that they are sometimes referred to as the Holy Grail of biology and the Great Conundrum in biogerontology. From an evolutionary perspective, ageing is due to a failure of selection that is caused either by declining strength of selection after the onset of sexual reproduction (Medawar’s theory and Charlesworth’s model) or pleiotropic constraints (Williams’ theory). According to the disposable soma theory, which was proposed by Kirkwood and Holliday, ageing is driven by the accumulation of damage during life and failures of defensive and repair mechanisms as the more an animal expends on sexual reproduction, the less it can expend on bodily maintenance, and vice versa. Although these standard models rule out the possibility that ageing is programmed, there is no consensus about the nature of ageing within the life history in current biogerontology. Interestingly, empirical studies show that there are molecular instructions for ageing and evolutionarily conserved mechanisms for ageing, which seems inconsistent with the idea that ageing is a matter of neglect or a consequence of a failure of selection due to pleiotropic constraints. Here, selected arguments for programmed (i.e. either determined and adaptive or prearranged but non-adaptive) and non-programmed ageing are discussed. Recent advances in biogerontology that cast new light on these problems are outlined here in the context of the idea that the pace of ageing can act as an adaptation in nature, even though ageing is non-programmed and non-adaptive.
27
Jordana, Xavier, Nekane Marín-Moratalla, Daniel DeMiguel, Thomas M. Kaiser, and Meike Köhler. "Evidence of correlated evolution of hypsodonty and exceptional longevity in endemic insular mammals." Proceedings of the Royal Society B: Biological Sciences 279, no. 1741 (April 25, 2012): 3339–46. http://dx.doi.org/10.1098/rspb.2012.0689.
Abstract:
Here, we test whether the increase in tooth height in insular endemics results from the expansion of the dietary niche under resource limitation, as widely considered, or whether it represents an investment in dental durability in response to the selection for extended longevity under low levels of extrinsic mortality. We tested these hypotheses in the extremely hypsodont fossil bovid Myotragus balearicus from the Balearic Islands, an ideal model to study the evolutionary trends on islands. Dental abrasion was significantly lower in the insular bovid than in highly hypsodont continental artiodactyls, suggesting that feeding habits are not the sole driving force behind increased crown height. However, the estimated longevity for M. balearicus based on dental durability was two times that predicted from body mass. Survivorship curves confirm that an extraordinarily large number of individuals approached the longevity of the species. Our results, hence, provide evidence that hypsodonty in insular endemics is the outcome of selection for increased durability of the permanent dentition in association with an extended lifespan. In the context of insularity, our results lend additional support to the disposable soma theory of ageing confirming the dependency of somatic maintenance and repair on lifespan, and its control by resource availability and extrinsic mortality.
28
Maklakov, Alexei A., Hanne Carlsson, Philip Denbaum, Martin I. Lind, Brian Mautz, Andrea Hinas, and Simone Immler. "Antagonistically pleiotropic allele increases lifespan and late-life reproduction at the cost of early-life reproduction and individual fitness." Proceedings of the Royal Society B: Biological Sciences 284, no. 1856 (June 14, 2017): 20170376. http://dx.doi.org/10.1098/rspb.2017.0376.
Abstract:
Evolutionary theory of ageing maintains that increased allocation to early-life reproduction results in reduced somatic maintenance, which is predicted to compromise longevity and late-life reproduction. This prediction has been challenged by the discovery of long-lived mutants with no loss of fecundity. The first such long-lived mutant was found in the nematode worm Caenorhabditis elegans . Specifically, partial loss-of-function mutation in the age-1 gene, involved in the nutrient-sensing insulin/insulin-like growth factor signalling pathway, confers longevity, as well as increased resistance to pathogens and to temperature stress without appreciable fitness detriment. Here, we show that the long-lived age-1 ( hx546 ) mutant has reduced fecundity and offspring production in early-life, but increased fecundity, hatching success, and offspring production in late-life compared with wild-type worms under standard conditions. However, reduced early-life performance of long-lived mutant animals was not fully compensated by improved performance in late-life and resulted in reduced individual fitness. These results suggest that the age-1 ( hx546 ) allele has opposing effects on early-life versus late-life fitness in accordance with antagonistic pleiotropy (AP) and disposable soma theories of ageing. These findings support the theoretical conjecture that experimental studies based on standing genetic variation underestimate the importance of AP in the evolution of ageing.
29
Libertini, Giacinto. "Evolutionary Explanations of the “Actuarial Senescence in the Wild” and of the “State of Senility”." Scientific World JOURNAL 6 (2006): 1086–108. http://dx.doi.org/10.1100/tsw.2006.209.
Abstract:
A large set of data suggests that progressive reduction of fitness and senile decay in vertebrates are in correlation with the decline of cell replication capacities. However, the limits in such capacities are hardly explained in evolutionarily terms by current gerontological theories that rule out fitness decline as something genetically determined and regulated, and therefore somehow favored by natural selection.Four theories are tested as possible explanations of the “increasing mortality with increasing chronological age in populations in the wild” (“IMICAW”[1]), alias “actuarial senescence in the wild”[2], and of the observed negative correlation between extrinsic mortality and the ratio between deaths due to intrinsic mortality and deaths due to extrinsic mortality. Only the theory attributing an adaptive value to IMICAW allows an evolutionary explanation for it and for the aforesaid inverse correlation, while the other three theories (“mutation accumulation”, “antagonistic pleiotropy”, and “disposable soma” th.) even predict a positive correlation.Afterwards, the same theories are tested as possible explanations for the “state of senility”[3], namely the deteriorated state of individuals in artificially protected conditions (captivity, civilization, etc.) at ages rarely or never observable in the wild. With the distinction between “damage resulting from intrinsic living processes”[4], alias “age changes”[5], and “age-associated diseases”[4,5], the same theory explaining IMICAW allows a rational interpretation of the first category of phenomena while another theory, the “mutation accumulation” hypothesis, gives an immediate interpretation for the second category.The current gerontological paradigm explaining the increasing mortality with increasing chronological age as consequence of insufficient selection should be restricted to the “age-associated diseases”. For IMICAW, it should be substituted with the concept of a physiologic phenomenon genetically determined by a balance of opposite selective pressures — strictly in terms of kin selection — and, for “age changes”, with the action of the same IMICAW-causing mechanisms at ages when selection becomes ineffective.
30
Chmielewski, Piotr, Krzysztof Borysławski, and Bartłomiej Strzelec. "Contemporary views on human aging and longevity." Anthropological Review 79, no. 2 (June 1, 2016): 115–42. http://dx.doi.org/10.1515/anre-2016-0010.
Abstract:
Abstract Aging is currently stimulating intense interest of both researchers and the general public. In developed countries, the average life expectancy has increased by roughly 30 years within the last century, and human senescence has been delayed by around a decade. Although aging is arguably the most familiar aspect of human biology, its proximate and ultimate causes have not been elucidated fully and understood yet. Nowadays there are two main approaches to the ultimate causes of aging. These are deterministic and stochastic models. The proximate theories constitute a distinct group of explanations. They focus on mechanistic causes of aging. In this view, there is no reason to believe that there is only one biological mechanism responsible for aging. The aging process is highly complex and results from an accumulation of random molecular damage. Currently, the disposable soma theory (DST), proposed by Thomas Kirkwood, is the most influential and coherent line of reasoning in biogerontology. This model does not postulate any particular mechanism underpinning somatic defense. Therefore, it is compatible with various models, including mechanistic and evolutionary explanations. Recently, however, an interesting theory of hyper-function of mTOR as a more direct cause of aging has been formulated by Mikhail Blagosklonny, offering an entirely different approach to numerous problems and paradoxes in current biogerontology. In this view, aging is quasi-programmed, which means that it is an aimless continuation of developmental growth. This mTOR-centric model allows the prediction of completely new relationships. The aim of this article is to present and compare the views of both parties in the dispute, based on the results of some recent experimental studies, and the contemporary knowledge of selected major aspects of human aging and longevity
31
Lagopoulos, A. P. "Postmodernism, Geography, and the Social Semiotics of Space." Environment and Planning D: Society and Space 11, no. 3 (June 1993): 255–78. http://dx.doi.org/10.1068/d110255.
Abstract:
The nucleus of postmodern philosophy and theory is derived primarily from French neostructuralist writings. The ontological foundation of such literature is the idealist rejection of the possibility of knowing reality and, as a consequence, the enclosure of the subject within the signifying universe, which in turn results in the exaltation of the signifying processes as the only social processes. The same emphasis, but through nonverbal means, is demonstrated by postmodern architectural and urban design. In geography, however, postmodernism is interpreted differently. In two recent books (by Soja and by Harvey) the postmodern era in human geography is related to the heightened importance of space for social reality and theory. But the split of geography itself between Marxist geography on the one hand, and behavioural and humanistic geography on the other, shows the pertinence of the signifying dimension for the field of geography. In this paper, it is argued that the roles of space and meaning are equally important for geography, and it is proposed that an analysis of the signifying aspect of space may be achieved through semiotics, currently the most complete and sophisticated theory of meaning and culture. The main problem for geography, which is addressed in the final section of this paper, is the integration of a renewed version of the semiotics of space with an equally renewed Marxist geography, the most powerful explanatory approach to geography we have at our disposal.
32
Dutkiewicz, Jacek. "SOME ADVANCES IN NONWOVEN STRUCTURES FOR ABSORBENCY, COMFORT AND AESTHETICS." AUTEX Research Journal 2, no. 3 (September 1, 2002): 153–65. http://dx.doi.org/10.1515/aut-2002-020306.
Abstract:
Abstract Modern disposable articles for personal and health care should offer excellent absorbency as well as comfort in use, need to be aesthetic and ensure discretion. There are numerous challenges facing the designers of nonwoven fabrics for absorption of body fluids, which result from various engineering contradictions. Combining all necessary functions, i.e. fluid acquisition, distribution and retention, in one uniform, simple composite made of fibers and superabsorbent polymer particles may be problematic. One can easily predict from theory that improving one parameter will result in a deterioration of another function. High-performance, multifunctional unitary structures require separation of functional components and their placement in a nonwoven web in a predetermined, oriented fashion. Some examples of such structures are proposed here and the experimental test results are discussed to demonstrate the advantages of the studied materials. The aesthetics of the finished article as well as the comfort of their use depend mainly on the bulk and mechanical properties of the absorbent core, such as integrity, softness and pliability. The paper provides some examples of engineered nonwoven webs having these desired attributes.
33
Lee, Hyun-Jae. "Hatred in the Digital Age : Fear of Self-destruction and Imaginary Sealing." Sookmyung Research Institute of Humanities 12 (October 31, 2022): 1–29. http://dx.doi.org/10.37123/th.2022.12.1.
Abstract:
This article shows that hatred is performed in the imaginary sealing of the fragmented bodily self, by analyzing Sigmund Freud's concept “das Unheimliche (the uncanny)”, Julia Kristeva's concept “abject” and Jacques Lacan's theory of “mirror stage”. To this end, this article first analyses the Freud's psychoanalysis and the Kristeva's theory of language and argue that hatred is closely linked to the uncanny fear of confronting abjects that remind us our death. And through the urban theory of Edward Soja and Celeste Oralquiaga, it is argued that the digital urbanization in postmetropolis which constitutes in de-territorialization and hybridization tends to trigger a mental breakdown surrounded by the fear of self-destruction. Finally, I insist with Lacan that some digital citizens respond to this fear by imaginatively sealing their fragmented egos through integrated ego images in the digital mirror. In this imaginary sealing are the fragmented egos excluded and the abjects hated.
34
Ustyukova, Valentina Vladimirovna. "Transfer of agricultural lands to lands of other categories: some issues of theory and practice of law enforcement." Право и политика, no. 8 (August 2023): 1–12. http://dx.doi.org/10.7256/2454-0706.2023.8.43928.
Abstract:
The Federal Law "On the Transfer of Lands or Land Plots from One Category to Another" (hereinafter referred to as Law No. 172-FZ) was adopted in December 2004. Since then, the socio-economic situation in the country and the legislation have changed significantly. However, they were not actually reflected in the Law, since only minor changes were made to it during almost 19 years of operation of the law. Over the past time, a lot of experience has been accumulated in theoretical understanding and practical application of this law, which is discussed in this article. The author does not pretend to be a comprehensive disclosure of the topic, since it is impossible to do this in one article. Nevertheless, the article reflects the author's position on a number of controversial issues of the theory and practice of legal regulation of the relations under consideration.The scientific novelty of the work consists in the study on the basis of formal legal and comparative legal methods of the latest judicial practice, the formulation of proposals to eliminate the legal uncertainty identified in the course of the work of some concepts used in the Law and other proposals to improve legislation in the field under consideration. In the light of solving the problem of rational use of agricultural land and preventing the unjustified disposal of agricultural land from use in the agricultural sector, the scientific understanding of controversial theoretical and practical issues of the transfer of these lands to lands of other categories is of particular relevance.
35
Nasihun, Taufiqurrahman. "Successful Aging." Sains Medika 6, no. 1 (June 7, 2015): 1. http://dx.doi.org/10.26532/sainsmed.v6i1.334.
Abstract:
The emerging concept of successful aging is based on evidence that in healthy individual when they get aged, there are considerable variations in physiological functions alteration. Some people exhibiting greater, but others very few or no age related alteration. The first is called poor aging and the later is called successful pattern of aging (Lambert SW, 2008). Thus, in the simple words the successful aging concept is define as an opportunity of old people to stay active and productive condition despite they get aged chronologically. Aging itself might be defined as the progressive accumulation of changes with time associated with or responsible for the ever-increasing susceptibility to disease and death which accompanies advancing age (Harman D, 1981). The time needed to accumulate changes is attributable to aging process. The marked emerging questions are how does aging happen and where does aging start?To answer these questions and because of the complexity of aging process, there are more than 300 aging theories have been proposed to explain how and where aging occured and started respectively. There are too many to enumerate theories and classification of aging process. In summary, all of these aging theories can be grouped into three clusters: 1. Genetics program theory, this theory suggests that aging is resulted from program directed by the genes; 2. Epigenetic theory, in these theory aging is resulted from environmental random events not determined by the genes; 3. Evolutionary theory, which propose that aging is a medium for disposal mortal soma in order to avoid competition between organism and their progeny for food and space, did not try to explain how aging occur, but possibly answer why aging occur (De la Fuente. 2009). Among the three groups of aging theories, the epigenetic theory is useful to explain and try to solve the enigma of aging which is prominently caused by internal and external environmental influences.There are gradual decline of physiological functions in human after becoming adult in life. The declining of physiological functions might be define as decrease in protein synthesis capacity, bone mineral density, immunological function, strength and muscle mass, and otherwise increase in fat accumulation (Rudman D, et al. 1982; Charmpilas N, et al. 2015). Epidemiologic study indicated that the predominant cause of morbidity, mortality, and reduced longevity in cohort were acute and chronic inflammatory as well as oxidative stress, resulted from environmental inflammations, infections, obesity, and social distress. Acute inflammatory is commonly caused by biological agent, especially both or either bacterial and or viral, whereas chronic inflammatory is related to environmental inflammagen, obesity, and social distress (Sone H et al. 2010) Chronic oxidative stress injures cells particularly in regulatory sytem such as endocrine, nervous, immune, and the neuro-endocrine immune communication by wich cell loss its homeostasis regulatory and cannot preserve health (De la Fuente. 2009). Subsequently, it will impaire homeostasis that leads to an increase in the morbidity and mortality of aging. Likely, answer to the question of where aging start is from the mitochondrial cells of regulatory system. Various evidences indicate that the rate of mitochondrial oxygen radical generation, the degree of membrane fatty acid unsaturation, and oxidative damage to mitochodrial DNA are lower in the long-live species compared to short live species (Braja G, 2004). Several studies also indicate that majority of human adults die due to complication of atherosclerosis, cancer, dimentia, whereas in healthy age invariably accompanied by muscle weakness, and make them frail, disabled, and dependent before eventually died. Such disability prominently caused by skeletal muscle weakness due to diminution of muscle mass and its nerve, osteoarthrirtis, and others chronic degenerative diseases related to oxidative stress (Payton OD, et al. 2012) Furthermore, physical weakness in aging people, generally marked by imbalanced, immobility, low durability, and physical frailty. Consequences of such physical frailty are easy to fall, bone fracture, dependence, hence decreasing daily activity (Buchner DM, et al. 1992; Lambert SW, 2008)To ameliorate the impairment of homeostasis, a caloric restriction but not malnutrition diet and adequate exercise (aerobic, resistance, and streching) can be adopted to neutralize as part of the oxidative and inflammatory stress and to strengthen and increase muscle mass (Payton OD, et al. 2012; Park S, et al. 2012). In special individual condition, like as overweight or obesity, smoker and frequently use of mobile phone, proper antioxidant supplementation can be considered. In addition, caloric restriction, food intake is intentionally reduced by 30–50% has been shown to delay the aging process in mice by decreasing the levels of histone deacetylase2 (HDAC2), which other wise increases during the normal aging process (Mercken EM, et al. 2012).
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Nasihun, Taufiqurrahman. "Successful Aging." Sains Medika : Jurnal Kedokteran dan Kesehatan 6, no. 1 (June 7, 2015): 1. http://dx.doi.org/10.30659/sainsmed.v6i1.334.
Abstract:
The emerging concept of successful aging is based on evidence that in healthy individual when they get aged, there are considerable variations in physiological functions alteration. Some people exhibiting greater, but others very few or no age related alteration. The first is called poor aging and the later is called successful pattern of aging (Lambert SW, 2008). Thus, in the simple words the successful aging concept is define as an opportunity of old people to stay active and productive condition despite they get aged chronologically. Aging itself might be defined as the progressive accumulation of changes with time associated with or responsible for the ever-increasing susceptibility to disease and death which accompanies advancing age (Harman D, 1981). The time needed to accumulate changes is attributable to aging process. The marked emerging questions are how does aging happen and where does aging start?To answer these questions and because of the complexity of aging process, there are more than 300 aging theories have been proposed to explain how and where aging occured and started respectively. There are too many to enumerate theories and classification of aging process. In summary, all of these aging theories can be grouped into three clusters: 1. Genetics program theory, this theory suggests that aging is resulted from program directed by the genes; 2. Epigenetic theory, in these theory aging is resulted from environmental random events not determined by the genes; 3. Evolutionary theory, which propose that aging is a medium for disposal mortal soma in order to avoid competition between organism and their progeny for food and space, did not try to explain how aging occur, but possibly answer why aging occur (De la Fuente. 2009). Among the three groups of aging theories, the epigenetic theory is useful to explain and try to solve the enigma of aging which is prominently caused by internal and external environmental influences.There are gradual decline of physiological functions in human after becoming adult in life. The declining of physiological functions might be define as decrease in protein synthesis capacity, bone mineral density, immunological function, strength and muscle mass, and otherwise increase in fat accumulation (Rudman D, et al. 1982; Charmpilas N, et al. 2015). Epidemiologic study indicated that the predominant cause of morbidity, mortality, and reduced longevity in cohort were acute and chronic inflammatory as well as oxidative stress, resulted from environmental inflammations, infections, obesity, and social distress. Acute inflammatory is commonly caused by biological agent, especially both or either bacterial and or viral, whereas chronic inflammatory is related to environmental inflammagen, obesity, and social distress (Sone H et al. 2010) Chronic oxidative stress injures cells particularly in regulatory sytem such as endocrine, nervous, immune, and the neuro-endocrine immune communication by wich cell loss its homeostasis regulatory and cannot preserve health (De la Fuente. 2009). Subsequently, it will impaire homeostasis that leads to an increase in the morbidity and mortality of aging. Likely, answer to the question of where aging start is from the mitochondrial cells of regulatory system. Various evidences indicate that the rate of mitochondrial oxygen radical generation, the degree of membrane fatty acid unsaturation, and oxidative damage to mitochodrial DNA are lower in the long-live species compared to short live species (Braja G, 2004). Several studies also indicate that majority of human adults die due to complication of atherosclerosis, cancer, dimentia, whereas in healthy age  invariably accompanied by muscle weakness, and make them frail, disabled, and dependent before eventually died. Such disability prominently caused by skeletal muscle weakness due to diminution of muscle mass and its nerve, osteoarthrirtis, and others chronic degenerative diseases related to oxidative stress (Payton OD, et al. 2012) Furthermore, physical weakness in aging people, generally marked by imbalanced, immobility, low durability, and physical frailty. Consequences of such physical frailty are easy to fall, bone fracture, dependence, hence decreasing daily activity (Buchner DM, et al. 1992; Lambert SW, 2008)To ameliorate the impairment of homeostasis, a caloric restriction but not malnutrition diet and adequate exercise (aerobic, resistance, and streching) can be adopted to neutralize as part of the oxidative and inflammatory stress and to strengthen and increase muscle mass (Payton OD, et al. 2012; Park S, et al. 2012). In special individual condition, like as overweight or obesity, smoker and frequently use of mobile phone, proper antioxidant supplementation can be considered. In addition, caloric restriction, food intake is intentionally reduced by 30–50% has been shown to delay the aging process in mice by decreasing the levels of histone deacetylase2 (HDAC2), which other wise increases during the normal aging process (Mercken EM, et al. 2012).
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Wechuli, Simiyu, Daniel Munga, and Risper Magwa. "Determination of Some Selected Heavy Metals in Effluents from Lubricants Manufacturing and Associated Contamination of Oysters (Crassostrea cucullata) and Soil near Discharge Points in Mombasa, Kenya." Journal of Chemistry 2, no. 1 (November 25, 2023): 14–24. http://dx.doi.org/10.47672/jchem.1663.
Abstract:
Purpose: Available reports on heavy metal contamination along the Kenyan coastal zone focused on concentration levels in marine and coastal waters, sediments and biota, with indications of potential sources. However, information on contribution of specific sources to the heavy metal load into the marine and coastal environment is scanty or unavailable. Thus, this study addressed the need to assess specific potential sources and their contribution to heavy metal contamination. The generated data can be applied for monitoring discharge loads of heavy metals from lubricant manufacturing processes into the environment, its level of contamination to the environment and the potential risk to man through food chain.
Materials and Methods: Concentrations of selected heavy metals Cd, Cr, Cu, Pb, and Hg in effluents filtrates, residues (SPM), Oysters (Crassostrea cucullata) and soil samples were determined using ICP-OES. The procedures of the analytical methods and instruments used were validated with analysis of a multi-element certified reference material (CRM IAEA-452) for the elements Cd, Cr, Cu, Pb and Hg in the effluent samples and standard reference material (SRM 1566b) from National institute standards and technology for the elements Cd, Cr, Cu, Pb and Hg in the marine bivalve tissues. Physico – chemical parameters Temperature, PH, Conductivity, Dissolved oxygen and Total organic carbon were also determined in the effluent samples. Sampling was done in the year 2021 and 2022. Effluent samples were collected from OLA energy Kenya limited, VIVO energy Kenya limited and TOTAL energy Kenya limited. Oyster samples and soil sediment samples were collected from Makupa creek. Data analysis was carried out using (SPSS) for Windows (Version 16) and one way analysis of variance (ANOVA) at 95% confidence level. The difference in mean concentrations of heavy metals within and between groups were considered significant at P˂0.05. The interrelationships of heavy metals contamination in the samples were determined using the Pearson correlation coefficient. It was considered significant at P value ˂0.05.
Findings: This study showed presence of heavy metals that varied in concentrations in effluents samples, soils samples and Oyster samples. The mean concentrations of heavy metals in the effluents filtrates ranged as follows Pb = 0.0038±0.0004 mg/l – 0.0025 ± 0.003 mg/l, Cu = 0.0054±0.0038 mg/l – 0.0019±0.0002 mg/l, Cr = 0.0071±0.0021mg/l – 0.0045±0.0022 mg/l, Cd = 0.0041±0.0026 mg/l – 0.0013±0.0001 mg/l and Hg = 0.0063±0.0018 mg/l – 0.0026±0.0004 mg/l. The range of values for the mean concentrations of the heavy metals in the Oysters showed that Pb = 0.0227±0.0091mg/kg – 0.019 ± 0.006 mg/kg, Cu = 0.0618±0.0171mg/kg – 0.0601±0.0168 mg/kg, Cr = 0.0265 ± 0.0277 mg/kg – 0.0152 ± 0.0009 mg/kg, Cd = 0.0464±0.0282 mg/kg – 0.0273 ± 0.0117 mg/kg and Hg = 0.0264±0.0158 mg/kg – 0.025±0.0080 mg/kg. The range of values for the mean concentrations of the heavy metals in the soil samples showed that Pb = 0.0523 ± 0.0189 mg/kg – 0.0447±0.0181 mg/kg, Cu = 0.3010 ± 0.0282 mg/kg – 0.2437 ± 0.2690 mg/kg, Cr = 0.6564 ± 0.1468 mg/kg – 0.5862 ± 0.3073 mg/kg, Cd = 0.5434 ± 0.2207 mg/kg – 0.3506±0.2157 mg/kg and Hg = 0.2679 ± 0.1923 mg/kg – 0.2366±0.1584 mg/kg. The range values for the Physico-chemical parameters in the effluent samples were PH = 7.31±0.198 – 6.53±0.459, Temperature = 27.53±0.378oC – 23.3±0.2oC, Dissolved oxygen = 6.81±0.191mg/l – 3.11±0.242 mg/l, conductivity = 2740.0±901.041 uS/cm – 1523.33±55.075 uS/cm, Total organic carbon = 15.18±1.2750 mg/l – 0.92±0.1026 mg/l. Concentrations of heavy metals were at safe limits set by WHO, US – EPA and NEMA (2017) except Hg in soil samples was slightly above permissible limits. Concentration of mercury was lower in effluent filtrates and effluents residues samples than in soil and Oysters samples.
Implications to Theory, Practice and Policy: This study recommends that frequent inspection be carried out on wastes emanating from industries, at its disposal sites and in living organisms at the vicinity of the wastes disposal sites. Industrialists should adopt best practices of wastes disposal and management to reduce emissions of harmful substances into the environment. Public education and awareness should be carried out to enlighten the residents about the impacts on health upon interaction with the polluted environment and feeding on organisms that reside in such contaminated environments.
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Metelev, O. P. "Some issues of digitalization process in criminal proceedings." Прикарпатський юридичний вісник, no. 3 (2022): 90–94. http://dx.doi.org/10.32782/pyuv.v3.2022.20.
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Ranguelov, Boyko. "Beautifulness of Some Space Objects and Other Unusual Properties." Current Trends in Engineering Science (CTES) 2, no. 1 (November 3, 2022): 1–4. http://dx.doi.org/10.54026/ctes/1014.
Abstract:
During the last years the interest of the people and scientists to the planets of Solar system and far space objects with relation to the search of potential exoplanets is increasing constantly. One of the reasons is that space missions are more and more oriented to the possible colonization of near-field space bodies. Among all engineering problems of exploring the properties of the space objects one is very exciting. This is related to the properties adapted to the human feelings and senses. More people are interested to the properties available to our senses like smell, taste, dactylic sensations, sounds, etc. Most of these feelings are adapted to the Earth’s atmosphere and humans’ evolution of senses. The question is – how the human being with its senses will have feelings on the space bodies? The complicated engineering solutions can transform the chemical components and physical properties of the space objects, obtained by different remote sensing methods and spacecraft’s missions to the familiar to humans’ feelings. This short presentation is targeted to the description about some organoleptic properties of the space objects (taste, smell, sounds), including as well such subjective feeling like “beautifulness”. The analysis shows that the nice-looking space bodies frequently are not very hostable to the humans. Even more – they are really dangerous for the potential visitors.
40
Mustapha, A. L. "Profitability of Sesame Production in Some Selected Local Government Areas of Katsina State, Nigeria." Arid-zone Journal of Basic & Applied Research 1, no. 5 (October 15, 2022): 158–63. http://dx.doi.org/10.55639/607.3141.
Abstract:
The study analyzed the economics of sesame production in Katsina State, Nigeria. Farmers in Katsina State are mostly small-scale farmers and are often faced with the problem of low productivity and profitability. Despite the economic importance of sesame seed, export potentials and world demand, sesame producers are yet to achieve a significant increase in their output and income Primary data were collected from 90 selected sesame producers using a multistage sampling technique across Katsina State and interviewed using a structured questionnaire. Gross Margin (GM) model was used for data analysis. The results revealed that sesame producers in Katsina State incurred an average Total Variable Cost (TVC) of ₦117,942.28 with the cost of labour amounting to ₦46,611.50 which accounts for about 39.52% of the TVC of production. The result also revealed a positive gross margin of ₦118,469.29/Ha with a Return per Naira Invested (RNI) of ₦2.00. It was concluded that sesame production is an important and profitable enterprise in Katsina State based on a positive GM and RNI of ₦2.00. The study recommends that there should be more investment in the sesame production enterprise by the sesame farmers to increase output and profit. Effective extension services should be put in place by KTARDA to educate sesame farmers on improved production techniques while community-based organizations should be strengthened for accessing agricultural loans as a group.
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Mustapha, A. L., and A. Suleiman. "Analysis of Poverty Status among Sesame Producers in Some Selected Local Government Areas of Katsina State, Nigeria." Arid-zone Journal of Basic & Applied Research 1, no. 5 (October 15, 2022): 173–82. http://dx.doi.org/10.55639/607.3242.
Abstract:
The study analyzed the poverty status among sesame producers in some selected Local Government Areas (LGAs) of Katsina State, Nigeria. Poverty status among farming households in Katsina State is high despite being a state suitable for sesame production. Sesame is a high value. Primary data were collected from 90 selected sesame producers using a multistage sampling technique across the LGAs of Katsina State prominent in sesame production and interviewed using a structured questionnaire. Descriptive statistics and the Foster, Greer and Thorbecke (FGT) poverty model were used for data analysis. The results on the socioeconomic characteristics of producers revealed a mean age of 43 years, an average household size of 8 persons and a mean year of experience in sesame production of 7 years. The average farm size was 2.42 ha with an average annual income of ₦272,596.16. The result of the analysis of the sesame producer’s poverty status revealed a high poverty incidence of 86.67%. It was concluded that poverty incidence was very high among sesame producers in Katsina State. The study recommends that there should be more investment in the sesame production enterprise by the sesame farmers to increase output and profit and consequently improve their poverty status. Effective extension services should be put in place to educate sesame farmers to improve production techniques and management practices for increased output.
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"Evolution of senescence: late survival sacrificed for reproduction." Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences 332, no. 1262 (April 29, 1991): 15–24. http://dx.doi.org/10.1098/rstb.1991.0028.
Abstract:
In so far as it is associated with declining fertility and increasing mortality, senescence is directly detrimental to reproductive success. Natural selection should therefore act in the direction of postponing or eliminating senescence from the life history. The widespread occurrence of senescence is explained by observing that (i) the force of natural selection is generally weaker at late ages than at early ages, and (ii) the acquisition of greater longevity usually involves some cost. Two convergent theories are the ‘antagonistic pleiotropy’ theory, based in population genetics, and the ‘disposable soma’ theory, based in physiological ecology. The antagonistic pleiotropy theory proposes that certain alleles that are favoured because of beneficial early effects also have deleterious later effects. The disposable soma theory suggests that because of the competing demands of reproduction less effort is invested in the maintenance of somatic tissues than is necessary for indefinite survival.
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Schneider, Augusto, Tatiana D. Saccon, Driele N. Garcia, Bianka M. Zanini, José V. V. Isola, Jéssica D. Hense, Joao A. Alvarado-Rincón, et al. "The Interconnections Between Somatic and Ovarian Aging in Murine Models." Journals of Gerontology: Series A, October 10, 2020. http://dx.doi.org/10.1093/gerona/glaa258.
Abstract:
Abstract The mammalian female is born with a limited ovarian reserve of primordial follicles. These primordial follicles are slowly activated throughout the reproductive lifecycle, thereby determining lifecycle length. Once primordial follicles are exhausted, women undergo menopause, which is associated with several metabolic perturbations and a higher mortality risk. Long before exhaustion of the reserve, females experience severe declines in fertility and health. As such, significant efforts have been made to unravel the mechanisms that promote ovarian aging and insufficiency. In this review, we explain how long-living murine models can provide insights in the regulation of ovarian aging. There is now overwhelming evidence that most life-span–extending strategies, and long-living mutant models simultaneously delay ovarian aging. Therefore, it appears that the same mechanisms that regulate somatic aging may also be modulating ovarian aging and germ cell exhaustion. We explore several potential contributing mechanisms including insulin resistance, inflammation, and DNA damage—all of which are hallmarks of cellular aging throughout the body including the ovary. These findings are in alignment with the disposable soma theory of aging, which dictates a trade-off between growth, reproduction, and DNA repair. Therefore, delaying ovarian aging will not only increase the fertility window of middle age females, but may also actively prevent menopausal-related decline in systemic health parameters, compressing the period of morbidity in mid-to-late life in females.
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Crosland, Agathe, Thierry Rigaud, Aude Balourdet, and Yannick Moret. "“Born with a silver spoon in the mouth has bad sides too”: Experimentally increasing growth rate enhances individual quality but accelerates reproductive senescence in females of the mealworm beetle, Tenebrio molitor." Frontiers in Ecology and Evolution 10 (August 12, 2022). http://dx.doi.org/10.3389/fevo.2022.915054.
Abstract:
Senescence occurs because of the decline of the strength of selection with age, allowing late-life reduced performances not being counter selected. From there, several phenomena may explain late-life reduced performances, such as the accumulation of deleterious mutations, the expression of pleiotropic genes or the existence of resource trade-offs between early and late performances. This latter phenomenon is at the core of the disposable soma theory of aging, which predicts that growth and early-life reproduction have costs that increase reproductive and actuarial senescence. Whereas the impact of the cost of early reproduction on reproductive and actuarial senescence has been extensively studied, that of the cost of growth remains overlooked and often inconclusive, possibly because of confounding effects associated with the procedures used to manipulate growth rate. Here, we investigated the cost of growth rate and its impact on reproductive senescence and longevity of females of the mealworm beetle, Tenebrio molitor. For this purpose, we generated insects with contrasted growth rates by raising groups of them in conditions below, above and optimal relative humidity (RH: 55, 85 and 70%, respectively) during the larval stage. The resulting adult females then bred, under the same optimal RH conditions, early in life, then later in life and were followed there until death. We found that larvae grown under the highest relative humidity exhibited the highest larval growth rate, thanks to both shorter growth duration and the achievement of heavier pupae mass. Adult females from this favorable growing condition lived longer, were more fecund early in life, but suffered from lower late-life reproductive investment. Our study shows that growth rate, which is highly dependent on the early-life environment, is an important factor modulating adult reproductive senescence, through the occurrence of early-late life trade-offs.
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Crosland, Agathe, Thierry Rigaud, Charlène Develay, and Yannick Moret. "Growth and longevity modulation through larval environment mediate immunosenescence and immune strategy of Tenebrio molitor." Immunity & Ageing 21, no. 1 (January 12, 2024). http://dx.doi.org/10.1186/s12979-023-00409-w.
Abstract:
Abstract Background The Disposable Soma Theory of aging suggests a trade-off between energy allocation for growth, reproduction and somatic maintenance, including immunity. While trade-offs between reproduction and immunity are well documented, those involving growth remain under-explored. Rapid growth might deplete resources, reducing investment in maintenance, potentially leading to earlier or faster senescence and a shorter lifespan. However, rapid growth could limit exposure to parasitism before reaching adulthood, decreasing immunity needs. The insect immunity’s components (cellular, enzymatic, and antibacterial) vary in cost, effectiveness, and duration. Despite overall immunity decline (immunosenescence), its components seem to age differently. We hypothesize that investment in these immune components is adjusted based on the resource cost of growth, longevity, and the associated risk of parasitism. Results We tested this hypothesis using the mealworm beetle, Tenebrio molitor as our experimental subject. By manipulating the larval environment, including three different temperatures and three relative humidity levels, we achieved a wide range of growth durations and longevities. Our main focus was on the relationship between growth duration, longevity, and specific immune components: hemocyte count, phenoloxidase activity, and antibacterial activity. We measured these immune parameters both before and after exposing the individuals to a standard bacterial immune challenge, enabling us to assess immune responses. These measurements were taken in both young and older adult beetles. Upon altering growth duration and longevity by modifying larval temperature, we observed a more pronounced investment in cellular and antibacterial defenses among individuals with slow growth and extended lifespans. Intriguingly, slower-growing and long-lived beetles exhibited reduced enzymatic activity. Similar results were found when manipulating larval growth duration and adult longevity through variations in relative humidity, with a particular focus on antibacterial activity. Conclusion The impact of growth manipulation on immune senescence varies by the specific immune parameter under consideration. Yet, in slow-growing T. molitor, a clear decline in cellular and antibacterial immune responses with age was observed. This decline can be linked to their initially stronger immune response in early life. Furthermore, our study suggests an immune strategy favoring enhanced antibacterial activity among slow-growing and long-lived T. molitor individuals.
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Fathi Attia, Alaa. "Some Aspects of the Syntax of the Arabic Legislative Sentence." International Journal of Arabic-English Studies 18, no. 1 (January 1, 2018). http://dx.doi.org/10.33806/ijaes2000.18.1.6.
Abstract:
The analysis of the internal structure of the Arabic legislative sentence is of immediate relevance to several interrelated disciplines including discourse analysis, contrastive linguistics and translation pedagogy. Nonetheless, little, if any, systematic corpus-based research has been conducted to verify the largely impressionistic and intuitive claims made about the syntax of this sentence type. This paper provides a statistical analysis of the syntax of this sentence type in three legislative texts: the Iraqi Companies Law, the Emirati Labor Law and the Jordanian Penal Code. The results show that passivization is a common feature, that the number of words in the Arabic sentence is less than half of its counterpart in English, that complex sentences are more frequent than other types of sentences and that case descriptions are less frequent than syntactic discontinuities. The research findings are significant to both translators and translator trainers as they identify the most salient features of Arabic legislative text and place such features at the disposal of these practitioners for the purposes of teaching and learning. However, despite the revealing conclusions, more research needs to be carried out on larger corpora not only in this sub-genre but also in other areas of legal Arabic..
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"Cardio-and-Hepatoprotective Benefits of Some Spices in Wistar Rats Induced with Metabolic Syndrome." Tropical Journal of Natural Product Research 6, no. 10 (November 1, 2022): 1707–14. http://dx.doi.org/10.26538/tjnpr/v6i10.25.
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"In vitro Antioxidant Activities of Some Re(I) Metal Carbonyls Synthesized from Isatin Derivatives." Tropical Journal of Natural Product Research 6, no. 10 (November 1, 2022): 1723–26. http://dx.doi.org/10.26538/tjnpr/v6i10.28.