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1

Reproductive life-span and sources of mortality for alternative male life-history strategies in  

E-print Network

in sockeye salmon, Oncorhynchus nerka Stephanie M. Carlson, Harry B. Rich, Jr., and Thomas P. Quinn Abstract-killed, stranded), and reproductive life-span of male sockeye salmon, Oncorhynchus nerka (Walbaum in Artedi, 1792 par les goélands, échouage) et la durée de la vie reproductive de saumons rouges, Oncorhynchus nerka

Carlson, Stephanie

2

Reproduction & life I. Reproductive cycles  

E-print Network

Reproduction & life histories I. Reproductive cycles II. Reproduction in Amphibians III. Reproduction in Reptiles IV. Parental care V. Life Histories #12;I. Reproductive cycles A. Environmental In amphibians: Oogonia are self-renewing stem cells that persist for the life of the frog l Can generate a new

Dever, Jennifer A.

3

Life Span Well-Being  

ERIC Educational Resources Information Center

This chapter, rooted in life span developmental research and theory, examines domains of subjective well-being: emotional, social, and psychological. What is the impact of these domains on the learner's experience of education? It invites the reader to consider implications for learning through the use of learners' narratives.

Wolf, Mary Alice

2005-01-01

4

Reproduction & life I. Reproductive cycles  

E-print Network

1 Reproduction & life histories I. Reproductive cycles II. Modes of Fertilization III. Asexual;2 OOGENESIS in amphibians Oogonia are self-renewing stem cells that persist for the life of the frog Can of oocytes in the frog. During the first 3 years of life, three cohorts of oocytes are produced. The drawings

Dever, Jennifer A.

5

Reproduction & life I. Reproductive cycles  

E-print Network

1 Reproduction & life histories I. Reproductive cycles II. Modes of Fertilization III. Asexual that persist for the life of the frog Can generate a new cohort of oocytes each year Ova energetically more is encased w/shell Growth of oocytes in the frog. During the first 3 years of life, three cohorts of oocytes

Dever, Jennifer A.

6

What You Should Know about Your Reproductive Time Span  

MedlinePLUS

WHATYOUSHOULDKNOWABOUT Your Reproductive Time Span S ocial norms have changed over the past few decades as women are delaying marriage, choosing not ... an older age. Even though there are more reproductive choices, and treatments for family building have broadened, ...

7

Phycoerythrin extends life span and health span of Caenorhabditis elegans.  

PubMed

In the present study, we tested the antioxidant activity of phycoerythrin (PE, an oligomeric light harvesting protein isolated from Lyngbya sp. A09DM) to curtail aging effects in Caenorhabditis elegans. Purified PE (100?g/ml) dietary supplement was given to C. elegans and investigated for its anti-aging potential. PE treatment improved the mean life span of wild type (N2)-animals from 15??0.1 to 19.9??0.3days. PE treatment also moderated the decline in aging-associated physiological functions like pharyngeal pumping and locomotion with increasing age of N2 worms. Moreover, PE treatment also enhanced the stress tolerance in 5-day-aged adults with increase in mean survival rate from 22.2??2.5 to 41.6??2.5% under thermo stress and from 30.1??3.2 to 63.1??6.4% under oxidative (hydrogen peroxide)-stress. PE treatment was also noted to moderate the heat-induced expression of human amyloid-beta(A?1-42) peptide and associated paralysis in the muscle tissues of transgenic C. elegans CL4176 (Alzheimer's disease model). Effectiveness of PE in expanding the life span of mutant C. elegans, knockout for some up (daf-2 and age-1)- and down (daf-16)-stream regulators of insulin/IGF-1 signaling (IIS), shows the independency of PE effect from DAF-2-AGE-1-DAF-16 signaling pathway. Moreover, the inability of PE in expanding the life span of hsf-1 knockout C. elegans(sy441) suggests the dependency of PE effect on heat shock transcription factor (HSF-1) controlling stress-induced gene expression. In conclusion, our results demonstrated a novel anti-aging activity of PE which conferred increased resistance to cellular stress resulting in improved life span and health span of C. elegans. PMID:25304463

Sonani, Ravi Raghav; Singh, Niraj Kumar; Awasthi, Anjali; Prasad, Birendra; Kumar, Jitendra; Madamwar, Datta

2014-10-01

8

Life-Span Attachment: Complexities, Questions, Considerations  

ERIC Educational Resources Information Center

It is suggested that the complexities entailed in an analysis of life span attachment require consideration of so many interacting variables that a systems approach of some kind is needed for a beginning integration. (MS)

Knudtson, Frances Wynns

1976-01-01

9

Families as Life Span Experts  

ERIC Educational Resources Information Center

Professionals dealing with challenging behavior frequently operate detached from the other relationships in the child's life. This narrow approach has been called the unilateral strategy based on the belief that the child's outside world can be ignored and behavior can be changed by administering specific corrective interventions. In contrast,

Brendtro, Larry K.; Mitchell, Martin L.

2011-01-01

10

The Cost of Uncertain Life Span*  

PubMed Central

A considerable amount of uncertainty surrounds the length of human life. The standard deviation in adult life span is about 15 years in the U.S., and theory and evidence suggest it is costly. I calibrate a utility-theoretic model of preferences over length of life and show that one fewer year in standard deviation is worth about half a mean life year. Differences in the standard deviation exacerbate cross-sectional differences in life expectancy between the U.S. and other industrialized countries, between rich and poor countries, and among poor countries. Accounting for the cost of life-span variance also appears to amplify recently discovered patterns of convergence in world average human well-being. This is partly for methodological reasons and partly because unconditional variance in human length of life, primarily the component due to infant mortality, has exhibited even more convergence than life expectancy. PMID:22368324

Edwards, Ryan D.

2012-01-01

11

Reproduction & life I. Reproductive cycles  

E-print Network

reproduction IV. Parental care I. Reproductive cycles A. Environmental stimuli Moisture, temperature, food Straddle Glued Independent Foam nests Most frogs are oviporous Categorized by egg deposition location #12

Dever, Jennifer A.

12

Extraordinary long life spans in fruit-feeding butterflies can provide window on evolution of life span and aging  

PubMed Central

Information on the life span of organisms in the field is essential for elucidating the evolution of life span and aging. We present mark-recapture data (>30 000 marked individuals, >4000 recaptured at least once) on forty-seven species of fruit-feeding butterflies in a tropical forest in Uganda. The data reveal adult life spans in the field for several species that are significantly longer than previously recorded in Lepidoptera (butterflies and moths). Longevity records for species of which more than 100 individuals were recaptured ranged from 67 (Bicyclus auricruda) to 293 days (Euphaedra medon). In contrast to the majority of Lepidoptera which are short-lived, these all show exceptionally long life spans, and may thus help to better identify factors that affect aging, particularly when combined with information on temporal patterns in reproduction, strategies to avoid predation, and nutritional ecology. These key traits are readily measurable in butterflies and thus studies on fruit-feeding butterflies have much potential for gaining insight into the evolution of life span and aging, especially given the tradition of field-research on butterflies. PMID:17360139

Molleman, F.; Zwaan, B. J.; Brakefield, P.M.; Carey, J. R.

2007-01-01

13

A Life-Span Theory of Control  

Microsoft Academic Search

A life-span theory of development is presented that is based on the concepts of primary and secondary control. Primary control refers to behaviors directed at the external environment and involves attempts to change the world to fit the needs and desires of the individual. Secondary control is targeted at internal processes and serves to minimize losses in, maintain, and expand

Jutta Heckhausen; Richard Schulz

1995-01-01

14

Sensorimotor Synchronization across the Life Span  

ERIC Educational Resources Information Center

The present study investigates the contribution of general processing resources as well as other more specific factors to the life-span development of sensorimotor synchronization and its component processes. Within a synchronization tapping paradigm, a group of 286 participants, 6 to 88 years of age, were asked to synchronize finger taps with

Drewing, Knut; Aschersleben, Gisa; Li, Shu-Chen

2006-01-01

15

Spatial abilities across the adult life span.  

PubMed

The study investigates age-related effects across the adult life span on spatial abilities (testing subabilities based on a distinction between spatial visualization, mental rotation, and perspective taking) and spatial self-assessments. The sample consisted of 454 participants (223 women and 231 men) from 20 to 91 years of age. Results showed nonlinear age-related effects for spatial visualization and perspective taking but linear effects for mental rotation; few or no age-related effects were found for spatial self-assessments. Working memory accounted for only a small proportion of the variance in all spatial tasks and had no effect on spatial self-assessments. Overall, our findings suggest that the influence of age on spatial skills across the adult life span is considerable, but the effects of age change as a function of the spatial task considered, and the effect on spatial self-assessment is more marginal. PMID:23895173

Borella, Erika; Meneghetti, Chiara; Ronconi, Lucia; De Beni, Rossana

2014-02-01

16

Extending Cellular Life-Span with Telomerase  

NSDL National Science Digital Library

This Science magazine site contains full text of a research article: "Extension of Life-Span by Introduction of Telomerase into Normal Human Cells," by Andrea G. Bodnar et. al. (January 16, 1998; Vol 279, No. 5349--available in Adobe Acrobat [.pdf] format only) describes the Telomerase finding and includes a commentary by Titia de Lange of Rockefeller University's Laboratory of Cell Biology and Genetics. There has been a recent finding regarding telomerase, a gene which affects the mechanisms controlling human cell replication. The site above provides general information on telomerase, current telomere research, and the use of telemorase in medical practice. Telomerase increases the life-span of a cell, and is thus central to both aging and cancer.

Bodnar, Andrea G.; Chiu, Choy-Pik.; Frolkis, Maria.; Harley, Calvin B.; Holt, Shawn E.; Lichtsteiner, Serge.

1997-01-01

17

Attitudes Toward Death Across the Life Span.  

ERIC Educational Resources Information Center

To understand the change and development of people's attitudes toward death over the life span, a 62-item attitude questionnaire on death and dying was administered to 90 adults. Participants included five females and five males in each of nine age categories: 18-20, 20-24, 25-29, 30-34, 35-39, 40-49, 50-59, 60-64, and 65 or older. Participants

Maiden, Robert; Walker, Gail

18

Neoplastic Growth Through the Human Life Span  

Microsoft Academic Search

\\u000a The predominant view in the scientific literature concerning the incidence of cancers throughout the human life span is that\\u000a of an eschatological process with a linear increase in the incidence favored by aging of the organism. This is considered\\u000a The Dogma and, with rare exceptions, another more realistic view of the problem is not accepted. The idea of a cancer-aging

Alvaro Macieira-Coelho

19

78. VIEW SHOWING PLACEMENT OF LIFE SPAN SHOE ON PIER ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

78. VIEW SHOWING PLACEMENT OF LIFE SPAN SHOE ON PIER 6, LOOKING NORTH, March 5, 1935 - Sacramento River Bridge, Spanning Sacramento River at California State Highway 275, Sacramento, Sacramento County, CA

20

Stress Proteins in Aging and Life Span  

PubMed Central

Heat shock proteins (HSP) are molecular chaperones and have been implicated in longevity and aging in many species. Their major functions include, chaperoning misfolded or newly synthesized polypeptides, protecting cells from proteotoxic stress, and processing of immunogenic agents. These proteins are expressed constitutively and can be induced by stresses such as heat, oxidative stress and many more. The induction of HSP in aging could potentially maintain protein homeostasis and longevity by refolding the damaged proteins which accumulate during aging and are toxic to cells. HSP are shown to increase life span in model organisms such as C. elegans and decrease aging related proteotoxicity. Thus, decrease in HSP in aging is associated with disruption of cellular homeostasis which causes diseases such as cancer, cell senescence and neurodegeneration. HSP levels are decreased with aging in most organs including neurons. Aging also causes attenuation or alteration of many signaling pathways as well as the expression of transcription factors such as heat shock factor (HSF). The alteration in regulation and synthesis of Forkhead box O3a (FOXO3a) family of transcription factors as well as major antioxidant enzymes [manganese superoxide dismutase (MnSOD), catalase] are also seen in aging. Among many signaling mechanisms involved in altering longevity and aging, the insulin/IGF1 pathway and the Sir2 deacetylase are highly significant. This review inquires into the role of some of these pathways in longevity/aging along with HSP. PMID:23742046

Murshid, Ayesha; Eguchi, Takanori; Calderwood, Stuart K.

2014-01-01

21

A Motivational Theory of Life-Span Development  

Microsoft Academic Search

This article had four goals. First, the authors identified a set of general challenges and questions that a life-span theory of development should address. Second, they presented a comprehensive account of their Motivational Theory of Life-Span Development. They integrated the model of optimization in primary and secondary control and the action-phase model of developmental regulation with their original life-span theory

Jutta Heckhausen; Carsten Wrosch; Richard Schulz

2010-01-01

22

Teaching the Psychology of Aging: A Life-Span Perspective.  

ERIC Educational Resources Information Center

There is a vast body of literature devoted to an examination of life-span development. Several authors have described the characteristics of the life-span approach and have distinguished it from more traditional forms of psychology. Emphasis has been placed on the multidirectional and multidimensional nature of development and change, as well as

Seltzer, Mildred M.

23

Low-Level Chemiluminescence and Life Span of Drosophila melanogaster  

Microsoft Academic Search

Spontaneous photon emission (chemiluminescence, CL) as a monitor of free radical evolution in Drosophila melanogaster which had been maintained at 25 or 30C for 5 days after emergence was measured. When maintained at 30C the fly CL intensity was stronger than at 25C. Under the condition of the higher temperature, the fly life span was shorter (mean life span =

Tomoko Sato; Teruo Miyazawa; Masaki Kobayashi; Hideyuki Furukawa; Humio Inaba

1992-01-01

24

A Motivational Theory of Life-Span Development  

ERIC Educational Resources Information Center

This article had four goals. First, the authors identified a set of general challenges and questions that a life-span theory of development should address. Second, they presented a comprehensive account of their Motivational Theory of Life-Span Development. They integrated the model of optimization in primary and secondary control and the

Heckhausen, Jutta; Wrosch, Carsten; Schulz, Richard

2010-01-01

25

Partner Preferences Across the Life Span: Online Dating by Older Adults  

Microsoft Academic Search

Stereotypes of older adults as withdrawn or asexual fail to recognize that romantic relationships in later life are increasingly common. The authors analyzed 600 Internet personal ads from 4 age groups: 2034, 4054, 6074, and 75+ years. Predictions from evolutionary theory held true in later life, when reproduction is no longer a concern. Across the life span, men sought physical

Sheyna Sears-Roberts Alterovitz; Gerald A. Mendelsohn

2011-01-01

26

Partner Preferences Across the Life Span: Online Dating by Older Adults  

Microsoft Academic Search

Stereotypes of older adults as withdrawn or asexual fail to recognize that romantic relationships in later life are increasingly common. The authors analyzed 600 Internet personal ads from 4 age groups: 2034, 4054, 6074, and 75+ years. Predictions from evolutionary theory held true in later life, when reproduction is no longer a concern. Across the life span, men sought physical

Sheyna Sears-Roberts Alterovitz; Gerald A. Mendelsohn

2009-01-01

27

Health span approximates life span among many supercentenarians: compression of morbidity at the approximate limit of life span.  

PubMed

We analyze the relationship between age of survival, morbidity, and disability among centenarians (age 100-104 years), semisupercentenarians (age 105-109 years), and supercentenarians (age 110-119 years). One hundred and four supercentenarians, 430 semisupercentenarians, 884 centenarians, 343 nonagenarians, and 436 controls were prospectively followed for an average of 3 years (range 0-13 years). The older the age group, generally, the later the onset of diseases, such as cancer, cardiovascular disease, dementia, and stroke, as well as of cognitive and functional decline. The hazard ratios for these individual diseases became progressively less with older and older age, and the relative period of time spent with disease was lower with increasing age group. We observed a progressive delay in the age of onset of physical and cognitive function impairment, age-related diseases, and overall morbidity with increasing age. As the limit of human life span was effectively approached with supercentenarians, compression of morbidity was generally observed. PMID:22219514

Andersen, Stacy L; Sebastiani, Paola; Dworkis, Daniel A; Feldman, Lori; Perls, Thomas T

2012-04-01

28

Mitochondrial function as a determinant of life span  

Microsoft Academic Search

Average human life expectancy has progressively increased over many decades largely due to improvements in nutrition, vaccination,\\u000a antimicrobial agents, and effective treatment\\/prevention of cardiovascular disease, cancer, etc. Maximal life span, in contrast,\\u000a has changed very little. Caloric restriction (CR) increases maximal life span in many species, in concert with improvements\\u000a in mitochondrial function. These effects have yet to be demonstrated

Ian R. Lanza; K. Sreekumaran Nair

2010-01-01

29

Reducing Calorie Intake as a Method for Prolonging Life Span  

Microsoft Academic Search

Senescence with age may be inevitable, or programmed. However, there seems to be no one single fundamental explanation for why senescence occurs. Strategies for prolonging human life have been a centre of focus for many researchers. One such suggested strategy is reducing calorie intake. Calorie restriction may lead to increased life expectancy, and maximum life span, and a delayed rate

Laura Quittenden

30

Cell resilience in species life spans: a link to inflammation?  

E-print Network

and to local temperature ele- vations. Systemically, acute phase immune reactions cause hypoglycemia shown generally consistent correlations with the species characteristic life spans of birds and mammals during inflammatory responses of innate immunity, particularly, resistance to reactive oxygen spe- cies

de Magalhães, João Pedro

31

A Motivational Theory of Life-Span Development  

PubMed Central

This article had four goals. First, the authors identified a set of general challenges and questions that a life-span theory of development should address. Second, they presented a comprehensive account of their Motivational Theory of Life-Span Development. They integrated the model of optimization in primary and secondary control and the action-phase model of developmental regulation with their original life-span theory of control to present a comprehensive theory of development. Third, they reviewed the relevant empirical literature testing key propositions of the Motivational Theory of Life-Span Development. Finally, because the conceptual reach of their theory goes far beyond the current empirical base, they pointed out areas that deserve further and more focused empirical inquiry. PMID:20063963

Heckhausen, Jutta; Wrosch, Carsten; Schulz, Richard

2010-01-01

32

A life span model of successful aging  

Microsoft Academic Search

To lay the foundation for our model, we first describe ex- isting conceptions of successful aging, underlying as- sumptions of development, and criteria for success. The model presented extends the discourse on this topic in three directions: (a) It frames the discussion of successful aging in the broader context of life course development; (b) it accounts for both normative and

Richard Schulz; Jutta Heckhausen

1996-01-01

33

Leaf life span of floating-leaved plants  

Microsoft Academic Search

Photosynthetic capacity of floating-leaved plants is relatively high comparable with terrestrial herbaceous plants, though floating-leaved plants have a much smaller biomass with a leaf area index seldom exceeding 2m2m-2. Their rather small biomass accumulation is related to higher turnover of leaf biomass or shorter leaf life span. Life span of floating leaves reported in the literature ranged mostly from 13

T. Tsuchiya

1991-01-01

34

Indy gene variation in natural populations confers fitness advantage and life span extension through transposon insertion  

PubMed Central

Natural selection acts to maximize reproductive fitness. However, antagonism between life span and reproductive success frequently poses a dilemma pitting the cost of fecundity against longevity. Here, we show that natural populations of Drosophila melanogaster harbor a Hoppel transposon insertion variant in the longevity gene Indy (I'm not dead yet), which confers both increased reproduction and longevity through metabolic changes. Heterozygosity for this natural long-lived variant has been maintained in isolates despite long-term inbreeding under laboratory conditions and advantageously confers increased fecundity. DNA sequences of variant chromosome isolates show evidence of selective sweep acting on the advantageous allele, suggesting that natural selection acts to maintain this variant. The transposon insertion also regulates Indy expression level, which has experimentally been shown to affect life span and fecundity. Thus, in the wild, evolution reaffirms that the mechanism of heterozygote advantage has acted upon the Indy gene to assure increased reproductive fitness and, coincidentally, longer life span through regulatory transposon mutagenesis. PMID:24519859

Zhu, Chen-Tseh; Chang, Chengyi; Reenan, Robert A.; Helfand, Stephen L.

2014-01-01

35

Understanding Aggressive Behavior Across the Life Span  

PubMed Central

Aggressive behavior is the observable manifestation of aggression and is often associated with developmental transitions and a range of medical and psychiatric diagnoses across the lifespan. As healthcare professionals involved in the medical and psychosocial care of patients from birth through death, nurses frequently encounterand may serve asboth victims and perpetrators of aggressive behavior in the workplace. While the nursing literature has continually reported research on prevention and treatment approaches, less emphasis has been given to understanding the etiology, including contextual precipitants of aggressive behavior. This paper provides a brief review of the biological, social, and environmental risk factors that purportedly give rise to aggressive behavior. Further, many researchers have focused specifically on aggressive behavior in adolescence and adulthood. Less attention has been given to understanding the etiology of such behavior in young children and older adults. This paper emphasizes the unique risk factors for aggressive behavior across the developmental spectrum, including childhood, adolescence, adulthood, and late life. Appreciation of the risk factors of aggressive behavior, and, in particular, how they relate to age-specific manifestations, can aid nurses in better design and implementation of prevention and treatment programs. PMID:22471771

Liu, Jianghong; Lewis, Gary; Evans, Lois

2012-01-01

36

Life span extension in Drosophila melanogaster induced by morphine.  

PubMed

The influence of morphine on the life span of Drosophila melanogaster fruit flies has been investigated. Morphine hydrochloride (MH) at concentrations of 0.01, 0.05 and 0.25 mg/ml was added to a medium starting from day 5 or 54 of imaginal life. Supplementation with MH starting from day 5 of imaginal life has resulted in significant increases in the mean life span of males at all concentrations studied. In females, a significant increase in life span compared with control was obtained only for those treated with 0.25 mg/ml MH. In flies with MH feeding from day 54, residual life span was significantly increased in both males and females after treatment with 0.05 mg/ml MH. The present data, together with those of our earlier study in mice (Dubiley et al. Probl Aging Longvity 9:331332, 2000) suggest that morphine supplementation can result in life extension in both vertebrate and invertebrate animal species. PMID:21061062

Dubiley, Tatyana A; Rushkevich, Yury E; Koshel, Natalya M; Voitenko, Vladimir P; Vaiserman, Alexander M

2011-06-01

37

Dietary Interventions to Extend Life Span and Health Span Based on Calorie Restriction  

PubMed Central

The societal impact of obesity, diabetes, and other metabolic disorders continues to rise despite increasing evidence of their negative long-term consequences on health span, longevity, and aging. Unfortunately, dietary management and exercise frequently fail as remedies, underscoring the need for the development of alternative interventions to successfully treat metabolic disorders and enhance life span and health span. Using calorie restriction (CR)which is well known to improve both health and longevity in controlled studiesas their benchmark, gerontologists are coming closer to identifying dietary and pharmacological therapies that may be applicable to aging humans. This review covers some of the more promising interventions targeted to affect pathways implicated in the aging process as well as variations on classical CR that may be better suited to human adaptation. PMID:20371545

Minor, Robin K.; Allard, Joanne S.; Younts, Caitlin M.; Ward, Theresa M.

2010-01-01

38

Regulatory Role of Proteasome in Determination of Platelet Life Span*  

PubMed Central

Limit of platelet life span (810 days) is determined by the activity of a putative internal clock composed of Bcl-2 family proteins, whereas the role of other molecular players in this process remains obscure. Here, we sought to establish a central role of proteasome in platelet life span regulation. Administration of mice with inhibitors of proteasome peptidase activity induced significant thrombocytopenia. This was associated with enhanced clearance of biotin-labeled platelets from circulation and reduction in average platelet half-life from 66 to 37 h. Cells pretreated in vitro with proteasome inhibitors exhibited augmented annexin V binding and a drop in mitochondrial transmembrane potential indicative of apoptotic cell death and decreased platelet life span. These cells were preferentially phagocytosed by monocyte-derived macrophages, thus linking proteasome activity with platelet survival. The decisive role of proteasome in this process was underscored from enhanced expression of conformationally active Bax in platelets with attenuated proteasome activity, which was consistent with pro-apoptotic phenotype of these cells. The present study establishes a critical role of proteasome in delimiting platelet life span ostensibly through constitutive elimination of the conformationally active Bax. These findings bear potential implications in clinical settings where proteasome peptidase activities are therapeutically targeted. PMID:23329846

Nayak, Manasa K.; Kulkarni, Paresh P.; Dash, Debabrata

2013-01-01

39

Decision-making heuristics and biases across the life span  

PubMed Central

We outline a contextual and motivational model of judgment and decision-making (JDM) biases across the life span. Our model focuses on abilities and skills that correspond to deliberative, experiential, and affective decision-making processes. We review research that addresses links between JDM biases and these processes as represented by individual differences in specific abilities and skills (e.g., fluid and crystallized intelligence, executive functioning, emotion regulation, personality traits). We focus on two JDM biasesthe sunk-cost fallacy (SCF) and the framing effect. We trace the developmental trajectory of each bias from preschool through middle childhood, adolescence, early adulthood, and later adulthood. We conclude that life-span developmental trajectories differ depending on the bias investigated. Existing research suggests relative stability in the framing effect across the life span and decreases in the SCF with age, including in later life. We highlight directions for future research on JDM biases across the life span, emphasizing the need for process-oriented research and research that increases our understanding of JDM biases in peoples everyday lives. PMID:22023568

Strough, JoNell; Karns, Tara E.; Schlosnagle, Leo

2013-01-01

40

Implications of Life-Span Developmental Psychology for Childhood Education.  

ERIC Educational Resources Information Center

This paper outlines the potential contributions and limitations of applying the life-span perspective of developmental psychology to childhood education. The long-range consequences of corrective, preventive, or optimizing endeavors are pointed out. Potential contributions to the establishment of educational goals as well as to the construction of

Montada, Leo; Filipp, Sigrun-Heide

41

Families and Drugs: A Life-Span Research Approach.  

ERIC Educational Resources Information Center

The study of human development and behavior from a life-span perspective is an area of growing interest, and the family is a natural laboratory for this study. Research in the area of drug abuse demonstrates that drug use is not limited to any one population segment or age group, but is pervasive across population subgroups. More and more evidence

Glynn, Thomas J.

42

Exceptional Cognitive Development: A Life Span Developmental Approach.  

ERIC Educational Resources Information Center

The belief that gifted children are more likely to have personality problems than "normal" individuals is not supported by research, but the image of the disturbed gifted child persists. This paper reviews research from a life-span developmental perspective to examine why this image persists. The paper critically examines the research of L.

Flom, Peter

43

Artistic creativity across the adult life span: An alternative approach  

Microsoft Academic Search

Conclusion The foregoing discussion attempts to present a preliminary exploration of the relationship between selected aspects of creative activity and life span developmental processes. It proposes some degree of synchronism between the maturational needs of the creative individual and both the forms of expression available to the artist through his\\/her selected artistic idiom and the predominant art ideology (or ideologies)

Amir Cohen-Shalev

1986-01-01

44

I. Introduction Limited life span and senescence are near-  

E-print Network

- chondrial function prolongs C. elegans life span (Dillin et al., 2002; Lee et al., 2003). Other pathways; Rogina et al., 2000), sensory perception (Apfeld & Kenyon, 1999), serotonin signal- ing (Sze et al., 2000 (Verbeke et al., 2001). Given the plethora of genes for which expression is altered in aging mice (Lee et

Mackay, Trudy F.C.

45

Minocycline Effect on Life and Health Span of Drosophila Melanogaster  

PubMed Central

Up-regulation of kynurenine (KYN) pathway of tryptophan (TRP) was suggested as one of the mechanisms of aging and aging-associated disorders. Genetic and pharmacological impairment of TRP KYN metabolism resulted in prolongation of life span in Drosophila models. Minocycline, an antibiotic with anti-inflammatory, antioxidant and neuroprotective properties independent of its antibacterial activity, inhibited KYN formation from TRP. Since minocycline is the only FDA approved for human use medication with inhibitory effect on TRP KYN metabolism, we were interested to study minocycline effect on life- and health-spans in Drosophila model. Minocycline (0.87mM) prolonged mean, median and maximum life span of wild-type Oregon Drosophila melanogaster of both genders. Minocycline (0.87 mM) stimulated vertical climbing in male flies. Minocycline dose-dependently decreased quantity and survivorship of pupae of filial generation. Minocycline might be a promising candidate drug for anti-aging intervention and treatment of aging-associated medical and psychiatric disorders. The role of TRP KYN metabolism in the mechanisms of minocycline-effect on life- and health-span might be elucidated by the future assessment of minocycline effects in Drosophila mutants naturally or artificially knockout for genes impacting the key enzymes of KYN pathway of TRP metabolism. PMID:23185716

Oxenkrug, Gregory; Navrotskaya, Valeriya; Vorobyova, Lyudmila; Summergrad, Paul

2012-01-01

46

Body image across the adult life span: stability and change  

Microsoft Academic Search

By far, the majority of studies investigating body image in adults have drawn samples from college populations within a very narrow age range. The purpose of the present paper is to review empirical research on the body image of adults older than the typical college student. There are marked changes in appearance across the adult life span, especially for women,

Marika Tiggemann

2004-01-01

47

Age Differences in Five Personality Domains across the Life Span  

ERIC Educational Resources Information Center

The present study addresses the issue of age differences in 5 personality domains across the life span in a cross-sectional study. In contrast to most previous studies, the present study follows a methodologically more rigorous approach to warrant that age-related differences in personality structure and mean level can be meaningfully compared. It

Allemand, Mathias; Zimprich, Daniel; Hendriks, A. A. Jolijn

2008-01-01

48

Women's Spirituality across the Life Span: Implications for Counseling  

ERIC Educational Resources Information Center

Women's spirituality has unique characteristics that are often ignored within the spirituality literature. The authors review the literature on women's spirituality to reveal the major themes women have identified as relevant to their spiritual journeys across the life span. Implications for counseling and ideas for practice are included after

Briggs, Michele Kielty; Dixon, Andrea L.

2013-01-01

49

Neuromodulation of Behavioral and Cognitive Development across the Life Span  

ERIC Educational Resources Information Center

Among other mechanisms, behavioral and cognitive development entail, on the one hand, contextual scaffolding and, on the other hand, neuromodulation of adaptive neurocognitive representations across the life span. Key brain networks underlying cognition, emotion, and motivation are innervated by major transmitter systems (e.g., the catecholamines

Li, Shu-Chen

2012-01-01

50

Suicide Notes of Adolescents: A Life-span Comparison  

Microsoft Academic Search

Utilizing suicide notes as the data source, this study begins to explore some psychological dimensions in adolescent suicide and to identify the differences and similarities of suicide across the life span. The method called for 80 notes, representing four developmental ages (i.e., adolescents, young adults, middle adults, old adults) to be analyzed for specific protocols on eight categories, i.e., unbearable

Antoon A. Leenaars; Erik Jan De Wilde; Susanne Wenckstern; Michael Kral

2001-01-01

51

Life Stress and Transitions in the Life Span  

Microsoft Academic Search

\\u000a The traditional life cycle of human beings include infancy, childhood, adolescence, and adulthood. Transitions exist within\\u000a each of the life cycles and such transitions produce stress. Life has many stressful life events that mark the movement from\\u000a one condition or cycle to another, and they produce substantial challenges in the lives of human beings. The purpose of this\\u000a volume is

Thomas W. Miller

52

Longevity: potential life span and health span enhancement through practice of the basic yoga meditation regimen.  

PubMed

This chapter briefly reviews recent psychological, physiological, molecular biological, and anthropological research which has important implications, both direct and indirect, for the recognition and understanding of the potential life span and health span enhancing effects of the basic yoga meditational regimen. This regimen consists of meditation, yogic breath control practices, physical exercises (of both a postural- and movement-based, including aerobic nature), and dietary practices. While each of these component categories exhibit variations in different schools, lineages, traditions, and cultures, the focus of this chapter is primarily on basic forms of relaxation meditation and breath control, as well as postural and aerobic physical exercises (e.g., yogic prostration regimens, see below), and a standard form of yogic or ascetic diet, all of which constitute a basic form of regimen found in many if not most cultures, though with variations. PMID:19735236

Bushell, William C

2009-08-01

53

Does Dietary Restriction Reduce Life Span in Male Fruit-feeding Butterflies?  

PubMed Central

Male life history and resource allocation is not frequently studied in aging and life span research. Here we verify that males of long-lived fruit-feeding butterfly species have reduced longevity on restricted diets (Beck 2007 Oecologia), in contrast to the common finding of longevity extension in dietary restriction experiments in Drosophila and some other organisms. Males of some of the most long-lived species of fruit-feeding butterflies were collected from Kibale Forest, Uganda, and kept on diets of either sugar or mashed banana. Seven out of eight species had non-significantly longer life spans on mashed banana diets. Data analysis using a time-varying Cox-model with species as covariate showed that males had reduced survival on the sugar diet during the first 35 days of captive life, but the effect was absent or reversed at more advanced ages. These results challenge the generality of dietary restriction as a way to extend life span in animals. We argue that such studies on males are promising tools for better understanding life history evolution and aging because males display a wider variety of tactics for obtaining reproductive success than females. PMID:19580860

Molleman, Freerk; Ding, Jimin; Boggs, Carol L.; Carey, James R.; Arlet, Malgorzata E.

2009-01-01

54

HSF-1-mediated cytoskeletal integrity determines thermotolerance and life span.  

PubMed

The conserved heat shock transcription factor-1 (HSF-1) is essential to cellular stress resistance and life-span determination. The canonical function of HSF-1 is to regulate a network of genes encoding molecular chaperones that protect proteins from damage caused by extrinsic environmental stress or intrinsic age-related deterioration. In Caenorhabditis elegans, we engineered a modified HSF-1 strain that increased stress resistance and longevity without enhanced chaperone induction. This health assurance acted through the regulation of the calcium-binding protein PAT-10. Loss of pat-10 caused a collapse of the actin cytoskeleton, stress resistance, and life span. Furthermore, overexpression of pat-10 increased actin filament stability, thermotolerance, and longevity, indicating that in addition to chaperone regulation, HSF-1 has a prominent role in cytoskeletal integrity, ensuring cellular function during stress and aging. PMID:25324391

Baird, Nathan A; Douglas, Peter M; Simic, Milos S; Grant, Ana R; Moresco, James J; Wolff, Suzanne C; Yates, John R; Manning, Gerard; Dillin, Andrew

2014-10-17

55

Variation of chromatic sensitivity across the life span.  

PubMed

Thresholds were measured along three directions in color space for detecting an equiluminant color change of a set of bars embedded in a larger field of spatio-temporal achromatic noise for observers ranging in age from 3 months to 86 years. Pre-verbal observers were assessed with a forced-choice preferential-looking technique while older observers responded orally or manually. Over the life span, thresholds could be described along each color axis tested by a curve with two trends. Thresholds decreased with each doubling of age by nearly a factor of two until adolescence. Thereafter, thresholds increased by a factor of 1.4-2 with each doubling of age. Sensitivity to chromatic differences varied similarly along all three axes tested, suggesting uniformity in the sensitivity of chromatic mechanisms across the life span. PMID:11163613

Knoblauch, K; Vital-Durand, F; Barbur, J L

2001-01-01

56

Developmental regulation across the life span: toward a new synthesis.  

PubMed

How can individuals regulate their own development to live happy, healthy, and productive lives? Major theories of developmental regulation across the life span have been proposed (e.g., dual-process model of assimilation and accommodation; motivational theory of life-span development; model of selection, optimization, and compensation), but they have rarely been integrated. We provide an integration of key processes and predictions postulated by the 3 theories. Moreover, we present evidence from 2 age-heterogeneous, cross-sectional studies showing that the different processes of developmental regulation proposed by the different theories center around 3 key processes (i.e., goal engagement, goal disengagement, and metaregulation), which are positively associated with age and well-being. We conclude by proposing an agenda for future research. PMID:22822930

Haase, Claudia M; Heckhausen, Jutta; Wrosch, Carsten

2013-05-01

57

Cognitive Impairment in Schizophrenia: A Life Span Perspective  

Microsoft Academic Search

Cognitive impairment is a core Feature oF schizophrenia. The evolution oF cognitive impairment over the liFe span may clariFy whether schizophrenia is best characterized as a neurodevelopmental or neurodegenerative disorder. Children who later develop schizophrenia show delayed language acquisition, intellectual impairment, and poorer academic perFormance than peers. These premorbid intellectual deFicits may worsen beFore illness onset. Although patients show pervasive

Brian F. ODonnell

2007-01-01

58

Rapamycin extends life- and health span because it slows aging  

PubMed Central

Making headlines, a thought-provocative paper by Neff, Ehninger and coworkers claims that rapamycin extends life span but has limited effects on aging. How is that possibly possible? And what is aging if not an increase of the probability of death with age. I discuss that the JCI paper actually shows that rapamycin slows aging and also extends lifespan regardless of its direct anti-cancer activities. Aging is, in part, MTOR-driven: a purposeless continuation of developmental growth. Rapamycin affects the same processes in young and old animals: young animals' traits and phenotypes, which continuations become hyperfunctional, harmful and lethal later in life. PMID:23934728

Blagosklonny, Mikhail V.

2013-01-01

59

Homeless Aging Veterans in Transition: A Life-Span Perspective  

PubMed Central

The need for counseling and career/educational services for homeless veterans has captured political and economic venues for more than 25 years. Veterans are three times more likely to become homeless than the general population if veterans live in poverty or are minority veterans. This mixed methods study emphasized a life-span perspective approach for exploring factors influencing normative aging and life-quality of 39 homeless veterans in Alabama and Florida. Seven descriptive quantitative and qualitative research questions framed the investigation. Study participants completed a quantitative survey reflecting their preferences and needs with a subset of the sample (N = 12) also participating in individual qualitative interview sessions. Thirty-two service providers and stakeholders completed quantitative surveys. Empirical and qualitative data with appropriate triangulation procedures provided interpretive information relative to a life-span development perspective. Study findings provide evidence of the need for future research efforts to address strategies that focus on the health and economic challenges of veterans before they are threatened with the possibility of homelessness. Implications of the study findings provide important information associated with the premise that human development occurs throughout life with specific characteristics influencing the individual's passage. Implications for aging/homelessness research are grounded in late-life transitioning and human development intervention considerations. PMID:24286010

Thompson, Carla J.; Bridier, Nancy L.

2013-01-01

60

Homeless aging veterans in transition: a life-span perspective.  

PubMed

The need for counseling and career/educational services for homeless veterans has captured political and economic venues for more than 25 years. Veterans are three times more likely to become homeless than the general population if veterans live in poverty or are minority veterans. This mixed methods study emphasized a life-span perspective approach for exploring factors influencing normative aging and life-quality of 39 homeless veterans in Alabama and Florida. Seven descriptive quantitative and qualitative research questions framed the investigation. Study participants completed a quantitative survey reflecting their preferences and needs with a subset of the sample (N = 12) also participating in individual qualitative interview sessions. Thirty-two service providers and stakeholders completed quantitative surveys. Empirical and qualitative data with appropriate triangulation procedures provided interpretive information relative to a life-span development perspective. Study findings provide evidence of the need for future research efforts to address strategies that focus on the health and economic challenges of veterans before they are threatened with the possibility of homelessness. Implications of the study findings provide important information associated with the premise that human development occurs throughout life with specific characteristics influencing the individual's passage. Implications for aging/homelessness research are grounded in late-life transitioning and human development intervention considerations. PMID:24286010

Thompson, Carla J; Bridier, Nancy L

2013-01-01

61

Synchronizing Loss with Life Over a Life Span: A Dynamic Perspective  

ERIC Educational Resources Information Center

Synchronizing loss with life is a dynamic journey. This article explores the myths, beliefs, and dynamics of loss and life. The purpose of the article is to help clinicians assist and support their clients with the difficulties of synchronizing loss with life as they progress on their life span journey.

Browning, Frank C.

2008-01-01

62

The Life Cycle and Life Span of Namibian Fairy Circles  

PubMed Central

In Namibia of southwestern Africa, the sparse grasslands that develop on deep sandy soils under rainfall between 50 and 100 mm per annum are punctuated by thousands of quasi-circular bare spots, usually surrounded by a ring of taller grass. The causes of these so-called fairy circles are unknown, although a number of hypotheses have been proposed. This paper provides a more complete description of the variation in size, density and attributes of fairy circles in a range of soil types and situations. Circles are not permanent; their vegetative and physical attributes allow them to be arranged into a life history sequence in which circles appear (birth), develop (mature) and become revegetated (die). Occasionally, they also enlarge. The appearance and disappearance of circles was confirmed from satellite images taken 4 years apart (2004, 2008). The frequency of births and deaths as a fraction of the total population of circles allowed the calculation of an approximate turnover rate, and from this, an estimate of circle lifespan. Lifespan appeared to vary with circle size, with small circles averaging about 24 years, and larger ones 4375 years. Overall lifespan averaged about 41 yr. A second, independent estimate of lifespan was made by revisiting circles 2 to 9 years after their clear status had been confirmed. This resulted in a lifespan estimate of about 60 years. Any causal explanation of fairy circles must include their birth, development and death, their mean lifespan and the variation of their features under different conditions. PMID:22761663

Tschinkel, Walter R.

2012-01-01

63

Absence of Strong Heterosis for Life Span and Other Life History Traits in Caenorhabditis Elegans  

PubMed Central

We have examined crosses between wild-type strains of Caenorhabditis elegans for heterosis effects on life span and other life history traits. Hermaphrodites of all wild strains had similar life expectancies but males of two strains had shorter life spans than hermaphrodites while males of two other strains lived longer than hermaphrodites. F(1) hermaphrodite progeny showed no heterosis while some heterosis for longer life span was detected in F(1) males. F(1) hybrids of crosses between two widely studied wild-type strains, N2 (var. Bristol) and Berg BO (var. Bergerac), were examined for rate of development, hermaphrodite fertility, and behavior; there was no heterosis for these life history traits. Both controlled variation of temperature and uncontrolled environmental variation affected the length of life of all genotypes. Significant G X E effects on life span were observed in comparisons of N2 and Berg BO hermaphrodites, or N2 hermaphrodites and males, or N2 and a Ts mutant strain (DH26). Nevertheless, within an experiment, environmental variation was minimal and life spans were quite replicable. PMID:8325483

Johnson, T. E.; Hutchinson, E. W.

1993-01-01

64

SNEV overexpression extends the life span of human endothelial cells  

SciTech Connect

In a recent screening for genes downregulated in replicatively senescent human umbilical vein endothelial cells (HUVECs), we have isolated the novel protein SNEV. Since then SNEV has proven as a multifaceted protein playing a role in pre-mRNA splicing, DNA repair, and the ubiquitin/proteosome system. Here, we report that SNEV mRNA decreases in various cell types during replicative senescence, and that it is increased in various immortalized cell lines, as well as in breast tumors, where SNEV transcript levels also correlate with the survival of breast cancer patients. Since these mRNA profiles suggested a role of SNEV in the regulation of cell proliferation, the effect of its overexpression was tested. Thereby, a significant extension of the cellular life span was observed, which was not caused by altered telomerase activity or telomere dynamics but rather by enhanced stress resistance. When SNEV overexpressing cells were treated with bleomycin or bleomycin combined with BSO, inducing DNA damage as well as reactive oxygen species, a significantly lower fraction of apoptotic cells was found in comparison to vector control cells. These data suggest that high levels of SNEV might extend the cellular life span by increasing the resistance to stress or by improving the DNA repair capacity of the cells.

Voglauer, Regina [Institute of Applied Microbiology, Department of Biotechnology, University of Natural Resources and Applied Life Sciences Muthgasse 18, A-1190 Vienna (Austria); Chang, Martina Wei-Fen [Institute of Applied Microbiology, Department of Biotechnology, University of Natural Resources and Applied Life Sciences Muthgasse 18, A-1190 Vienna (Austria); Dampier, Brigitta [Department of Obstetrics and Gynecology, Medical University of Vienna, A-1090 Vienna (Austria); Wieser, Matthias [Institute of Applied Microbiology, Department of Biotechnology, University of Natural Resources and Applied Life Sciences Muthgasse 18, A-1190 Vienna (Austria); Baumann, Kristin [Institute of Applied Microbiology, Department of Biotechnology, University of Natural Resources and Applied Life Sciences Muthgasse 18, A-1190 Vienna (Austria); Sterovsky, Thomas [Institute of Applied Microbiology, Department of Biotechnology, University of Natural Resources and Applied Life Sciences Muthgasse 18, A-1190 Vienna (Austria); Schreiber, Martin [Department of Obstetrics and Gynecology, Medical University of Vienna, A-1090 Vienna (Austria); Katinger, Hermann [Institute of Applied Microbiology, Department of Biotechnology, University of Natural Resources and Applied Life Sciences Muthgasse 18, A-1190 Vienna (Austria); Grillari, Johannes [Institute of Applied Microbiology, Department of Biotechnology, University of Natural Resources and Applied Life Sciences Muthgasse 18, A-1190 Vienna (Austria) and BMT Research Vienna (Austria)]. E-mail: j.grillari@iam.boku.ac.at

2006-04-01

65

Partner preferences across the life span: online dating by older adults.  

PubMed

Stereotypes of older adults as withdrawn or asexual fail to recognize that romantic relationships in later life are increasingly common. The authors analyzed 600 Internet personal ads from 4 age groups: 20-34, 40-54, 60-74, and 75+ years. Predictions from evolutionary theory held true in later life, when reproduction is no longer a concern. Across the life span, men sought physical attractiveness and offered status-related information more than women; women were more selective than men and sought status more than men. With age, men desired women increasingly younger than themselves, whereas women desired older men until ages 75 and over, when they sought men younger than themselves. PMID:19485668

Alterovitz, Sheyna Sears-Roberts; Mendelsohn, Gerald A

2009-06-01

66

Amino acid sources in the adult diet do not affect life span and fecundity in the fruit-feeding butterfly Bicyclus anynana  

PubMed Central

1. In tropical forests, the adults of many butterfly species feed on fruits rather than nectar from flowers and have long life spans. Rotting fruit and nectar differ from each other in many respects, including sources of amino acids and microbial life. If amino acids in the adult diet can be used for reproduction, this may have facilitated the evolution of extended life spans in this guild. 2. This issue was addressed by investigating effects of banana, yeast, and amino acids in the adult diet of the fruit-feeding butterfly Bicyclus anynana (Lepidoptera) on longevity and female reproductive output in two experiments. 3. Results showed that in the fruit-feeding butterfly B. anynana: (i) banana juice, but not sliced banana or added amino acids extend life span compared with a sugar solution of similar composition; (ii) compared with this sugar solution, other cohorts (banana juice-amino acid enriched) did not have significantly higher reproductive outputs; (iii) yeast does not represent a valuable source of nutrients; (iv) caloric restriction may cause decreased life span and rate of reproduction; and (v) increased rates of reproduction have a life span cost. PMID:19081752

Molleman, Freerk; Ding, Jimin; Wang, Jane-Ling; Brakefield, Paul M.; Carey, James R.; Zwaan, Bas J.

2008-01-01

67

Integrating the Life Course and Life-Span: Formulating Research Questions with Dual Points of Entry.  

ERIC Educational Resources Information Center

Life-span research typically begins with personal characteristics, life-course research with social context and roles. Using both points of entry will encourage interdisciplinary work as well as the study of person-context interactions. (Contains 30 references.) (SK)

Shanahan, Michael J.; Porfelli, Erik

2002-01-01

68

Aging, life span, and energetics under adult dietary restriction in lepidoptera.  

PubMed

Stressful conditions can affect resource allocation among different life-history traits. The effect of dietary restriction (DR) on longevity and reproduction has been studied in many species, but we know little about its effects on energetics, especially in flying animals that have high energy demand. We assessed the effects of DR on metabolic rate throughout the entire adult life span in two butterfly species, Colias eurytheme and Speyeria mormonia. We cut the food intake of adult females in half and measured resting metabolic rate (RMR) and flight metabolic rate (FMR) together with body mass repeatedly throughout life. In both species, DR reduced body mass, but mass-corrected FMR was not affected, indicating that flight capacity was retained. DR lowered RMR and reduced fecundity but had no effect on life span. FMR declined with age, but the rate of senescence was not affected by DR. In contrast, aging had a strong negative effect on RMR only in control females, whereas food-restricted females had more stable RMR throughout their lives. The results suggest that flight capacity is conserved during nutritional stress but that investment in flight and survival may negatively affect other important physiological processes when resources are limited. PMID:25244380

Niitepld, Kristjan; Perez, Alejandro; Boggs, Carol L

2014-01-01

69

Quantitative and Molecular Genetic Analyses of Mutations Increasing Drosophila Life Span  

PubMed Central

Understanding the genetic and environmental factors that affect variation in life span and senescence is of major interest for human health and evolutionary biology. Multiple mechanisms affect longevity, many of which are conserved across species, but the genetic networks underlying each mechanism and cross-talk between networks are unknown. We report the results of a screen for mutations affecting Drosophila life span. One third of the 1,332 homozygous Pelement insertion lines assessed had quantitative effects on life span; mutations reducing life span were twice as common as mutations increasing life span. We confirmed 58 mutations with increased longevity, only one of which is in a gene previously associated with life span. The effects of the mutations increasing life span were highly sex-specific, with a trend towards opposite effects in males and females. Mutations in the same gene were associated with both increased and decreased life span, depending on the location and orientation of the Pelement insertion, and genetic background. We observed substantialand sex-specificepistasis among a sample of ten mutations with increased life span. All mutations increasing life span had at least one deleterious pleiotropic effect on stress resistance or general health, with different patterns of pleiotropy for males and females. Whole-genome transcript profiles of seven of the mutant lines and the wild type revealed 4,488 differentially expressed transcripts, 553 of which were common to four or more of the mutant lines, which include genes previously associated with life span and novel genes implicated by this study. Therefore longevity has a large mutational target size; genes affecting life span have variable allelic effects; alleles affecting life span exhibit antagonistic pleiotropy and form epistatic networks; and sex-specific mutational effects are ubiquitous. Comparison of transcript profiles of long-lived mutations and the control line reveals a transcriptional signature of increased life span. PMID:20686706

Magwire, Michael M.; Yamamoto, Akihiko; Carbone, Mary Anna; Roshina, Natalia V.; Symonenko, Alexander V.; Pasyukova, Elena G.; Morozova, Tatiana V.; Mackay, Trudy F. C.

2010-01-01

70

Coping strategies: gender differences and development throughout life span.  

PubMed

Development during life-span implies to cope with stressful events, and this coping may be done with several strategies. It could be useful to know if these coping strategies differ as a consequence of personal characteristics. This work uses the Coping with Stress Questionnaire with this aim using a sample of 400 participants. Specifically, the effects of gender and age group (young people, middle age and elderly), as well as its interaction on coping strategies is studied. With regard to age, on one hand, it is hypothesised a decrement in the use of coping strategies centred in problem solving and social support seeking as age increases. On the other hand, the use of emotional coping is hypothesised to increase with age. With respect to gender, it is hypothesised a larger use of emotional coping and social support seeking within women, and a larger use of problem solving within men. A MANOVA found significant effects for the two main effects (gender and age) as well as several interactions. Separate ANOVAs allowed us to test for potential differences in each of the coping strategies measured in the CAE. These results partially supported the hypotheses. Results are discussed in relation to scientific literature on coping, age and gender. PMID:23156917

Melndez, Juan Carlos; Mayordomo, Teresa; Sancho, Patricia; Toms, Jos Manuel

2012-11-01

71

Colour Constancy Across the Life Span: Evidence for Compensatory Mechanisms  

PubMed Central

It is well known that the peripheral visual system declines with age: the yellowing of the lens causes a selective reduction of short-wavelength light and sensitivity losses occur in the cone receptor mechanisms. At the same time, our subjective experience of colour does not change with age. The main purpose of this large-scale study (n?=?185) covering a wide age range of colour-normal observers (1875 years of age) was to assess the extent to which the human visual system is able to compensate for the changes in the optical media and at which level of processing this compensation is likely to occur. We report two main results: (1) Supra-threshold parafoveal colour perception remains largely unaffected by the age-related changes in the optical media (yellowing of the lens) whereas our ability to discriminate between small colour differences is compromised with an increase in age. (2) Significant changes in colour appearance are only found for unique green settings under daylight viewing condition which is consistent with the idea that the yellow-blue mechanism is most affected by an increase in age due to selective attenuation of short-wavelength light. The data on the invariance of hue perception, in conjunction with the age-related decline in chromatic sensitivity, provides evidence for compensatory mechanisms that enable colour-normal human observers a large degree of colour constancy across the life span. These compensatory mechanisms are likely to originate at cortical sites. PMID:23667689

Wuerger, Sophie

2013-01-01

72

Effects of calorie restriction on life span of microorganisms  

PubMed Central

Calorie restriction (CR) in microorganisms such as budding and fission yeasts has a robust and well-documented impact on longevity. In order to efficiently utilize the limited energy during CR, these organisms shift from primarily fermentative metabolism to mitochondrial respiration. Respiration activates certain conserved longevity factors such as sirtuins and is associated with widespread physiological changes that contribute to increased survival. However, the importance of respiration during CR-mediated longevity has remained controversial. The emergence of several novel metabolically distinct microbial models for longevity has enabled CR to be studied from new perspectives. The majority of CR and life span studies have been conducted in the primarily fermentative Crabtree-positive yeasts Saccharomyces cerevisiae and Schizosaccharomyces pombe, but studies in primarily respiratory Crabtree-negative yeast and obligate aerobes can offer complementary insight into the more complex mammalian response to CR. Not only are microorganisms helping characterize a conserved cellular mechanism for CR-mediated longevity, but they can also directly impact mammalian metabolism as part of the natural gut flora. Here, we discuss the contributions of microorganisms to our knowledge of CR and longevity at the level of both the cell and the organism. PMID:20721547

Skinner, Craig

2010-01-01

73

Programmed life span in the context of evolvability.  

PubMed

Population turnover is necessary for progressive evolution. In the context of a niche with fixed carrying capacity, aging contributes to the rate of population turnover. Theoretically, a population in which death is programmed on a fixed schedule can evolve more rapidly than one in which population turnover is left to a random death rate. Could aging evolve on this basis? Quantitative realization of this idea is problematic, since the short-term individual fitness cost is likely to eliminate any hypothetical gene for programmed death before the long-term benefit can be realized. In 2011, one of us proposed the first quantitative model based on this mechanism that robustly evolves a finite, programmed life span. That model was based on a viscous population in a rapidly changing environment. Here, we strip this model to its essence and eliminate the assumption of environmental change. We conclude that there is no obvious way in which this model is unrealistic, and that it may indeed capture an important principle of nature's workings. We suggest aging may be understood within the context of the emerging science of evolvability. PMID:25141139

Mitteldorf, Joshua; Martins, Andr C R

2014-09-01

74

Life-Span Development of Self-Esteem and Its Effects on Important Life Outcomes  

Microsoft Academic Search

We examined the life-span development of self-esteem and tested whether self-esteem influences the development of important life outcomes, including relationship satisfaction, job satisfaction, occupational status, salary, positive and negative affect, depression, and physical health. Data came from the Longitudinal Study of Generations. Analyses were based on 5 assessments across a 12-year period of a sample of 1,824 individuals ages 16

Ulrich Orth; Richard W. Robins; Keith F. Widaman

2012-01-01

75

High-Resolution Mapping of Quantitative Trait Loci Affecting Increased Life Span in Drosophila melanogaster  

Microsoft Academic Search

Limited life span and senescence are near-universal characteristics of eukaryotic organisms, controlled by many interacting quantitative trait loci (QTL) with individually small effects, whose expression is sensitive to the environment. Analyses of mutations in model organisms have shown that genes affecting stress resistance and metabolism affect life span across diverse taxa. However, there is considerable seg- regating variation for life

Rhonda H. Wilson; Theodore J. Morgan; Trudy F. C. Mackay

2006-01-01

76

Increased expression of Drosophila Sir 2 extends life span in a dose-dependent manner  

PubMed Central

Sir2, a member of the sirtuin family of protein acylases, deacetylates lysine residues within many proteins and is associated with lifespan extension in a variety of model organisms. Recent studies have questioned the positive effects of Sir2 on lifespan in Drosophila. Several studies have shown that increased expression of the Drosophila Sir2 homolog (dSir2) extends life span while other studies have reported no effect on life span or suggested that increased dSir2 expression was cytotoxic. To attempt to reconcile the differences in these observed effects of dSir2 on Drosophila life span, we hypothesized that a critical level of dSir2 may be necessary to mediate life span extension. Using approaches that allow us to titrate dSir2 expression, we describe here a strong dose-dependent effect of dSir2 on life span. Using the two transgenic dSir2 lines that were reported not to extend life span, we are able to show significant life span extension when dSir2 expression is induced between 2 and 5-fold. However, higher levels decrease life span and can induce cellular toxicity, manifested by increased expression of the JNK-signaling molecule Puc phosphatase and induction of dnaJ-H. Our results help to resolve the apparently conflicting reports by demonstrating that the effects of increased dSir2 expression on life span in Drosophila are dependent upon dSir2 dosage. PMID:24036492

Whitaker, Rachel; Faulkner, Shakeela; Miyokawa, Reika; Burhenn, Lucas; Henriksen, Mark; Wood, Jason G.; Helfand, Stephen L.

2013-01-01

77

Energy, quiescence and the cellular basis of animal life spans Jeffrey A. Stuart , Melanie F. Brown  

E-print Network

a dormant, or quiescent state. In some animals, such as the nematode Caenorhabditis elegans, quiescence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 9. Animal cell life span in culture

Stuart, Jeffrey A.

78

Life-span development of self-esteem and its effects on important life outcomes.  

PubMed

We examined the life-span development of self-esteem and tested whether self-esteem influences the development of important life outcomes, including relationship satisfaction, job satisfaction, occupational status, salary, positive and negative affect, depression, and physical health. Data came from the Longitudinal Study of Generations. Analyses were based on 5 assessments across a 12-year period of a sample of 1,824 individuals ages 16 to 97 years. First, growth curve analyses indicated that self-esteem increases from adolescence to middle adulthood, reaches a peak at about age 50 years, and then decreases in old age. Second, cross-lagged regression analyses indicated that self-esteem is best modeled as a cause rather than a consequence of life outcomes. Third, growth curve analyses, with self-esteem as a time-varying covariate, suggested that self-esteem has medium-sized effects on life-span trajectories of affect and depression, small to medium-sized effects on trajectories of relationship and job satisfaction, a very small effect on the trajectory of health, and no effect on the trajectory of occupational status. These findings replicated across 4 generations of participants--children, parents, grandparents, and their great-grandparents. Together, the results suggest that self-esteem has a significant prospective impact on real-world life experiences and that high and low self-esteem are not mere epiphenomena of success and failure in important life domains. PMID:21942279

Orth, Ulrich; Robins, Richard W; Widaman, Keith F

2012-06-01

79

The Time of Our Lives: Life Span Development of Timing and Event Tracking  

ERIC Educational Resources Information Center

Life span developmental profiles were constructed for 305 participants (ages 4-95) for a battery of paced and unpaced perceptual-motor timing tasks that included synchronize-continue tapping at a wide range of target event rates. Two life span hypotheses, derived from an entrainment theory of timing and event tracking, were tested. A preferred

McAuley, J. Devin; Jones, Mari Riess; Holub, Shayla; Johnston, Heather M.; Miller, Nathaniel S.

2006-01-01

80

Qualitative Exploration of Acculturation and Life-Span Issues of Elderly Asian Americans  

ERIC Educational Resources Information Center

Awareness of aging issues across diverse populations begins the journey toward counselors becoming culturally competent across client life spans. Understanding the life-span experiences of cultural groups is important for helping professionals. The purpose of this research was to gain insight into the qualitative experiences of Asian American

Lee, Jee Hyang; Heo, Nanseol; Lu, Junfei; Portman, Tarrell Awe Agahe

2013-01-01

81

The Time of Our Lives: Life Span Development of Timing and Event Tracking  

E-print Network

in the range of event rates that produced effective timing across the life span; specifically, ageThe Time of Our Lives: Life Span Development of Timing and Event Tracking J. Devin McAuley Bowling and unpaced perceptual­motor timing tasks that included synchronize­continue tapping at a wide range of target

Liu, Taosheng

82

Exploratory and problem-solving consumer behavior across the life span.  

PubMed

Different cognitive functioning, social, and personality changes appear to occur systematically during the adult life span. This article synthesizes research on life span changes in order to develop age-specific models of shopping behavior. The models are tested within a naturalistic field study of shoppers. PMID:1890293

Lesser, J A; Kunkel, S R

1991-09-01

83

[Life span and longevity in representatives of creative professions].  

PubMed

The article presents data on mean age of death of 49 064 representatives of various creative professions: visual artists (painters, sculptors, architects, n = 8 458), musicians (composers, conductors, singers, pianists, violinists, etc. n = 7 883), writers and poets (n = 11 488), scientists (n = 21 235). The mean age of death among writers and poets was significantly (p < 0.001) less than that in visual artists, musicians and scientists whereas scientists lived longer than representatives of other categories (p < 0.001). Women lived longer than men of any studied categories (p < 0.02). It was shown that the mean age of death gradually but irregularly increased since the 1st century A. C. until the 20th century in any professional cohort. Visual artists-men in 20th century lived longer than in previous historical periods (p < 0.001). Scientists both females and males in 20th century lived longer then these in 19th century (p < 0.001). The first five places of long-livers among men belong to Nobel prize winners (78,8 yrs.), academicians (72,7 yrs.) and corresponding members of the Russian Academy of Sciences (71,7 yrs.), conductors (71,1 yrs.) and scientists (71,0 yrs.). Rock-musicians, author's song singer and poets lived less than other categories (43,6; 53,6 and 61,6 yrs. respectively). Among women leading long-livers were conductors (83,2 yrs.), harp-players (80,9 yrs.), academicians of the RAS (80,3 yrs.), clavesin-players (79,1 yrs.) and violinists (78,2 yrs.). Among women, less lived rock-musicians (37,6 yrs.), author's songs singers (51,4), horns and woodwinds instruments players (59,0 yrs.). Relative number of nonagenarians (90+) was much higher among women as compared to men. The values were as 43.75% of harp-players, 33.33% of conductors, 29.17% of architects, 20% of violinists and viola-players and 18.99% sculptors for women, and 16.67% of Nobel prize winners, 12.12% of conductors, 7.51% of academicians, 7.44% of violinists and 7.0% of scientists survived 90+ years among men. Centenarians were 8.33% of academicians and architects, 6.25% of harp-players and 4.22% of writers-poets among women, and only 0.76% of pianists, 0.45% of scientists and 0.42% of violinists were centenarians among men. Our data are in agreement with the opinion that high intellect and education directly correlate with longer life span and longevity. PMID:24640685

Anisimov, V N; Zharinov, G M

2013-01-01

84

Optimisation by Selection and Compensation: Balancing Primary and Secondary Control in Life Span Development.  

ERIC Educational Resources Information Center

Discusses individuals as producers of their life span developments, and examines individuals' selection of their life paths and their proneness to failure. Considers a model that explains individuals' optimization of their life course management in terms of selection of life paths and compensation for age-related losses such that potential for

Heckhausen, Jutta; Schulz, Richard

1993-01-01

85

Increased expression of Drosophila Sir2 extends life span in a dose-dependent manner.  

PubMed

Sir2, a member of the sirtuin family of protein acylases, deacetylates lysine residues within many proteins and is associated with lifespan extension in a variety of model organisms. Recent studies have questioned the positive effects of Sir2 on lifespan inDrosophila. Several studies have shown that increased expression of the Drosophila Sir2 homolog (dSir2) extends life span while other studies have reported no effect on life span or suggested that increased dSir2 expression was cytotoxic. To attempt to reconcile the differences in these observed effects of dSir2 on Drosophila life span, we hypothesized that a critical level of dSir2 may be necessary to mediate life span extension. Using approaches that allow us to titrate dSir2 expression, we describe here a strong dose-dependent effect of dSir2 on life span. Using the two transgenic dSir2 lines that were reported not to extend life span, we are able to show significant life span extension when dSir2 expression is induced between 2 and 5-fold. However, higher levels decrease life span and can induce cellular toxicity, manifested by increased expression of the JNK-signaling molecule Puc phosphatase and induction of dnaJ-H. Our results help to resolve the apparently conflicting reports by demonstrating that the effects of increased dSir2 expression on life span in Drosophila are dependent upon dSir2 dosage. PMID:24036492

Whitaker, Rachel; Faulkner, Shakeela; Miyokawa, Reika; Burhenn, Lucas; Henriksen, Mark; Wood, Jason G; Helfand, Stephen L

2013-09-01

86

Life history theory and human reproductive behavior  

Microsoft Academic Search

The purpose of this article is to develop a model of life history theory that incorporates environmental influences, contextual\\u000a influences, and heritable variation. I argue that physically or psychologically stressful environments delay maturation and\\u000a the onset of reproductive competence. The social context is also important, and here I concentrate on the opportunity for\\u000a upward social mobility as a contextual influence

Kevin MacDonald; California State

1997-01-01

87

Catatonia in autism: implications across the life span  

Microsoft Academic Search

BackgroundThere is increasing evidence that catatonia is an important source of impairment in adolescents and adults with autism.\\u000a \\u000a \\u000a \\u000a AimReview of the evaluation, diagnosis, differential diagnosis, and treatment of catatonia in autism.\\u000a \\u000a \\u000a \\u000a MethodPresentation and discussion of a case-vignette spanning early childhood to adulthood.\\u000a \\u000a \\u000a \\u000a ResultsAutistic and catatonic symptoms overlap, yet catatonia is diagnosable in about one of seven adolescents and young adults

Angelina Kakooza-Mwesige; Lee E. Wachtel; Dirk M. Dhossche

2008-01-01

88

A new approach for measuring the erythrocyte life span with a nonradioisotope.  

PubMed

The possibility of substituting a nonradioactive isotope of chromium for 51Cr was studied. Blood, from five dogs with varying erythrocyte life spans, was labeled with 50Cr and 51Cr and transfused autologously. Erythrocyte-bound 50Cr was determined by inductively coupled argon plasma mass spectrometry and 51Cr by measuring radioactivity. Erythrocyte life span determination derived from the two isotopes did not differ significantly. Our results suggest that 50Cr can provide a nonradioactive alternative to 51Cr for labeling erythrocytes for life span studies. PMID:2758685

Dever, M; Smith, J E; Hausler, D W

1989-05-31

89

Reproductive Termination in Female Japanese Monkeys: A Comparative Life History Perspective  

E-print Network

Reproductive Termination in Female Japanese Monkeys: A Comparative Life History Perspective MARY S, Canada KEY WORDS menopause; Macaca fuscata; life history; age and reproduction; reproductive senescence; reproductive termination ABSTRACT This study explores the question of reproductive termination (loss

Fedigan, Linda M.

90

Personality and self-esteem development across the life span  

Microsoft Academic Search

Over the past few decades, there has been an explosion of longitudinal research on the consistency of personality and related constructs such as self-esteem. This plethora of studies has provided suKcient evidence to move researchers toward consensus about the degree to which personality characteristics change over the life course. The emerging story, based on an accumulating body of empirical research,

Kali H. Trzesniewski; Richard W. Robins; Brent W. Roberts; Avshalom Caspi

2003-01-01

91

Extension of Life-Span with Superoxide Dismutase\\/Catalase Mimetics  

Microsoft Academic Search

We tested the theory that reactive oxygen species cause aging. We augmented the natural antioxidant systems of Caenorhabditis elegans with small synthetic superoxide dismutase\\/catalase mimetics. Treatment of wild-type worms increased their mean life-span by a mean of 44 percent, and treatment of prematurely aging worms resulted in normalization of their life-span (a 67 percent increase). It appears that oxidative stress

Simon Melov; Joanne Ravenscroft; Sarwatt Malik; Matt S. Gill; David W. Walker; Peter E. Clayton; Douglas C. Wallace; Bernard Malfroy; Susan R. Doctrow; Gordon J. Lithgow

2000-01-01

92

Copper supplementation increases yeast life span under conditions requiring respiratory metabolism  

Microsoft Academic Search

To further exploit yeast as a model for cellular aging we have modified the replicative life span assay to force respiration, by replacing glucose with the non-fermentable carbon source glycerol. The growth rates of several different strains varied greatly, with doubling times ranging from 2.7 to 7h. Life spans of all strains were lower on media containing glycerol than on

Paul A. Kirchman; Gabriela Botta

2007-01-01

93

The Time of Our Lives: Life Span Development of Timing and Event Tracking  

Microsoft Academic Search

Life span developmental profiles were constructed for 305 participants (ages 495) for a battery of paced and unpaced perceptual-motor timing tasks that included synchronize-continue tapping at a wide range of target event rates. Two life span hypotheses, derived from an entrainment theory of timing and event tracking, were tested. A preferred period hypothesis predicted a monotonic slowing of a preferred

J. Devin McAuley; Mari Riess Jones; Shayla Holub; Heather M. Johnston; Nathaniel S. Miller

2006-01-01

94

Copper supplementation increases yeast life span under conditions requiring respiratory metabolism.  

PubMed

To further exploit yeast as a model for cellular aging we have modified the replicative life span assay to force respiration, by replacing glucose with the non-fermentable carbon source glycerol. The growth rates of several different strains varied greatly, with doubling times ranging from 2.7 to 7 h. Life spans of all strains were lower on media containing glycerol than on media containing glucose. However, supplementation of glycerol-containing media with copper resulted in increases in life span of between 17 and 72%; life spans equivalent to or beyond those obtained on glucose media. Addition of copper to glucose medium had no effect on life span. Microarray analysis showed that genes responsible for high affinity import of copper display reduced expression upon addition of copper, while most genes showed no change in expression. No differences in growth rate, oxygen uptake, or the levels of subunit II of the copper-containing cytochrome c oxidase were found between cultures of yeast grown with or without copper supplementation. Copper supplementation greatly extended the life span of sod1 and sod2 strains, suggesting that addition of copper may reduce the generation of superoxide. Forcing yeast to respire places an emphasis on mitochondrial function and may aid in the identification of factors involved in aging in other respiratory-dependent organisms. PMID:17129597

Kirchman, Paul A; Botta, Gabriela

2007-02-01

95

The prolonged life-span of alveolar macrophages.  

PubMed

To further examine the half-life of alveolar macrophages, chimeric CD 45.2 mice were generated through bone marrow transplantation of donor CD 45.1 cells. Before administration of donor cells, recipient mice were divided into two cohorts: the first cohort received total body irradiation; the second cohort also received irradiation-however, the thorax, head, and upper extremities were shielded with lead. Flow cytometric analysis was then performed on blood, peritoneal, and bronchoalveolar lavage cells over time to quantify engraftment. The data generated for the unshielded cohort of mice revealed a macrophage half-life of 30 days. In the shielded cohort, however, we found that by 8 months there was negligible replacement of recipient alveolar macrophages by donor cells, despite reconstitution of the blood and peritoneum by donor bone marrow. Consistent with these findings, the mean fluorescent intensity of alveolar macrophages remained stable over a 4-week period after in vivo PKH26 dye loading. Together, these data show that previous alveolar macrophage half-life studies were confounded by the fact that they did not account for the toxic effects of irradiation conditioning regimens, and demonstrate that the bone marrow does not significantly contribute to the alveolar macrophage compartment during steady-state conditions. PMID:18192503

Murphy, Jaime; Summer, Ross; Wilson, Andrew A; Kotton, Darrell N; Fine, Alan

2008-04-01

96

Changes in completed family size and reproductive span in Anabaptist populations.  

PubMed

The Anabaptist Amish, Hutterite and Mennonite peoples trace their origins to the Reformation. Although they share certain beliefs, such as adult baptism and the separation of church and state, each group is culturally unique. The Hutterite and Amish are highly fertile and their populations exhibit stable rates of growth. These demographic characteristics reflect communal living among the Hutterites and labor intensive farming practices among the Amish. The Mennonites are the most receptive Anabaptist group to outside socioeconomic influences and provide a demographic contrast to the more conservative Amish and Hutterites. Demographic data collected during a study of aging in Mennonite population samples from Goessel and Meridian, Kansas, 1980, and Henderson, Nebraska, 1981, formed the basis of a cohort analysis in order to assess fertility change over time. Completed family size has decreased significantly in all three communities since 1870. Since the early 1900's the mean age of the mother at first birth has fluctuated but the mean age of mother at the birth of the last child is decreasing significantly for the communities of Goessel and Henderson, thus effectively shortening the reproductive span. The pattern is somewhat different for Meridian, the most conservative of the three communities. PMID:2707783

Stevenson, J C; Everson, P M; Crawford, M H

1989-02-01

97

'Willpower' over the life span: decomposing self-regulation  

PubMed Central

In the 1960s, Mischel and colleagues developed a simple marshmallow test to measure preschoolers ability to delay gratification. In numerous follow-up studies over 40?years, this test proved to have surprisingly significant predictive validity for consequential social, cognitive and mental health outcomes over the life course. In this article, we review key findings from the longitudinal work and from earlier delay-of-gratification experiments examining the cognitive appraisal and attention control strategies that underlie this ability. Further, we outline a set of hypotheses that emerge from the intersection of these findings with research on cognitive control mechanisms and their neural bases. We discuss implications of these hypotheses for decomposing the phenomena of willpower and the lifelong individual differences in self-regulatory ability that were identified in the earlier research and that are currently being pursued. PMID:20855294

Ayduk, Ozlem; Berman, Marc G.; Casey, B. J.; Gotlib, Ian H.; Jonides, John; Kross, Ethan; Teslovich, Theresa; Wilson, Nicole L.; Zayas, Vivian

2011-01-01

98

'Willpower' over the life span: decomposing self-regulation.  

PubMed

In the 1960s, Mischel and colleagues developed a simple 'marshmallow test' to measure preschoolers' ability to delay gratification. In numerous follow-up studies over 40?years, this 'test' proved to have surprisingly significant predictive validity for consequential social, cognitive and mental health outcomes over the life course. In this article, we review key findings from the longitudinal work and from earlier delay-of-gratification experiments examining the cognitive appraisal and attention control strategies that underlie this ability. Further, we outline a set of hypotheses that emerge from the intersection of these findings with research on 'cognitive control' mechanisms and their neural bases. We discuss implications of these hypotheses for decomposing the phenomena of 'willpower' and the lifelong individual differences in self-regulatory ability that were identified in the earlier research and that are currently being pursued. PMID:20855294

Mischel, Walter; Ayduk, Ozlem; Berman, Marc G; Casey, B J; Gotlib, Ian H; Jonides, John; Kross, Ethan; Teslovich, Theresa; Wilson, Nicole L; Zayas, Vivian; Shoda, Yuichi

2011-04-01

99

Theoretical Propositions of Life-Span Developmental Psychology: On the Dynamics between Growth and Decline.  

ERIC Educational Resources Information Center

Defines life-span developmental psychology as the study of constancy and change in behavior throughout the life course. Advances metatheoretical view regarding development. Stresses focus on the dynamic and continuous interplay between growth (gain) and decline (loss). Examines structural contextual factors and study of range of plasticity in

Baltes, Paul B.

1987-01-01

100

Quantitative trait loci for life span in Drosophila melanogaster: interactions with genetic background and larval density.  

PubMed Central

The genetic architecture of variation in adult life span was examined for a population of recombinant inbred lines, each of which had been crossed to both inbred parental strains from which the lines were derived, after emergence from both high and low larval density. QTL affecting life span were mapped within each sex and larval density treatment by linkage to highly polymorphic roo-transposable element markers, using a composite interval mapping method. We detected a total of six QTL affecting life span; the additive effects and degrees of dominance for all were highly sex- and larval environment-specific. There were significant epistatic interactions between five of the life span QTL, the effects of which also differed according to genetic background, sex, and larval density. Five additional QTL were identified that contributed to differences among lines in their sensitivity to variation in larval density. Further fine-scale mapping is necessary to determine whether candidate genes within the regions to which the QTL map are actually responsible for the observed variation in life span. PMID:10924473

Leips, J; Mackay, T F

2000-01-01

101

Enhanced Energy Metabolism Contributes to the Extended Life Span of Calorie-restricted Caenorhabditis elegans*  

PubMed Central

Caloric restriction (CR) markedly extends life span and improves the health of a broad number of species. Energy metabolism fundamentally contributes to the beneficial effects of CR, but the underlying mechanisms that are responsible for this effect remain enigmatic. A multidisciplinary approach that involves quantitative proteomics, immunochemistry, metabolic quantification, and life span analysis was used to determine how CR, which occurs in the Caenorhabditis elegans eat-2 mutants, modifies energy metabolism of the worm, and whether the observed modifications contribute to the CR-mediated physiological responses. A switch to fatty acid metabolism as an energy source and an enhanced rate of energy metabolism by eat-2 mutant nematodes were detected. Life span analyses validated the important role of these previously unknown alterations of energy metabolism in the CR-mediated longevity of nematodes. As observed in mice, the overexpression of the gene for the nematode analog of the cytosolic form of phosphoenolpyruvate carboxykinase caused a marked extension of the life span in C. elegans, presumably by enhancing energy metabolism via an altered rate of cataplerosis of tricarboxylic acid cycle anions. We conclude that an increase, not a decrease in fuel consumption, via an accelerated oxidation of fuels in the TCA cycle is involved in life span regulation; this mechanism may be conserved across phylogeny. PMID:22810224

Yuan, Yiyuan; Kadiyala, Chandra S.; Ching, Tsui-Ting; Hakimi, Parvin; Saha, Sudipto; Xu, Hua; Yuan, Chao; Mullangi, Vennela; Wang, Liwen; Fivenson, Elayne; Hanson, Richard W.; Ewing, Rob; Hsu, Ao-Lin; Miyagi, Masaru; Feng, Zhaoyang

2012-01-01

102

High-resolution mapping of quantitative trait loci affecting increased life span in Drosophila melanogaster.  

PubMed

Limited life span and senescence are near-universal characteristics of eukaryotic organisms, controlled by many interacting quantitative trait loci (QTL) with individually small effects, whose expression is sensitive to the environment. Analyses of mutations in model organisms have shown that genes affecting stress resistance and metabolism affect life span across diverse taxa. However, there is considerable segregating variation for life span in nature, and relatively little is known about the genetic basis of this variation. Replicated lines of Drosophila that have evolved increased longevity as a correlated response to selection for postponed senescence are valuable resources for identifying QTL affecting naturally occurring variation in life span. Here, we used deficiency complementation mapping to identify at least 11 QTL on chromosome 3 that affect variation in life span between five old (O) lines selected for postponed senescence and their five base (B) population control lines. Most QTL were sex specific, and all but one affected multiple O lines. The latter observation is consistent with alleles at intermediate frequency in the base population contributing to the response to selection for postponed senescence. The QTL were mapped with high resolution and contained from 12 to 170 positional candidate genes. PMID:16702433

Wilson, Rhonda H; Morgan, Theodore J; Mackay, Trudy F C

2006-07-01

103

How long will my mouse live? Machine learning approaches for prediction of mouse life span.  

PubMed

Prediction of individual life span based on characteristics evaluated at middle-age represents a challenging objective for aging research. In this study, we used machine learning algorithms to construct models that predict life span in a stock of genetically heterogeneous mice. Life-span prediction accuracy of 22 algorithms was evaluated using a cross-validation approach, in which models were trained and tested with distinct subsets of data. Using a combination of body weight and T-cell subset measures evaluated before 2 years of age, we show that the life-span quartile to which an individual mouse belongs can be predicted with an accuracy of 35.3% (+/-0.10%). This result provides a new benchmark for the development of life-span-predictive models, but improvement can be expected through identification of new predictor variables and development of computational approaches. Future work in this direction can provide tools for aging research and will shed light on associations between phenotypic traits and longevity. PMID:18840793

Swindell, William R; Harper, James M; Miller, Richard A

2008-09-01

104

Adolescents' ideas of normative life span development and personal future goals  

Microsoft Academic Search

We investigated how 57 adolescents (23 girls and 34 boys), aged 12 to 15 years, compared their idea of normative life span development to their personal future goals. A two-stage study (questionnaire and follow-up interview) included two open-ended life paths, measures for self-evaluation and self-other comparisons. Overlap of content categories in the life paths supported the relationship between individual goals

Lars-Erik Malmberg; Sonja Norrgard

1999-01-01

105

Increased internal and external bacterial load during Drosophila aging without life-span trade-off.  

PubMed

The role of microbial load during aging of the adult fruit fly Drosophila melanogaster is incompletely understood. Here we show dramatic increases in aerobic and anaerobic bacterial load during aging, both inside the body and on the surface. Scanning electron microscopy and cell staining analyses of the surface of aged flies detected structures resembling abundant small bacteria and bacterial biofilms. Bacteria cultured from laboratory flies included aerobic species Acetobacter aceti, Acetobacter tropicalis, and Acetobacter pasteurianus and anaerobic species Lactobacillus plantarum and Lactobacillus sp. MR-2; Lactobacillus homohiochii, Lactobacillus fructivorans, and Lactobacillus brevis were identified by DNA sequencing. Reducing bacterial load and antimicrobial peptide gene expression by axenic culture or antibiotics had no effect on life span. We conclude that Drosophila can tolerate a significant bacterial load and mount a large innate immune response without a detectable trade-off with life span; furthermore, microbes do not seem to limit life span under optimized laboratory conditions. PMID:17681150

Ren, Chunli; Webster, Paul; Finkel, Steven E; Tower, John

2007-08-01

106

Sir2-Independent Life Span Extension by Calorie Restriction in Yeast  

PubMed Central

Calorie restriction slows aging and increases life span in many organisms. In yeast, a mechanistic explanation has been proposed whereby calorie restriction slows aging by activating Sir2. Here we report the identification of a Sir2-independent pathway responsible for a majority of the longevity benefit associated with calorie restriction. Deletion of FOB1 and overexpression of SIR2 have been previously found to increase life span by reducing the levels of toxic rDNA circles in aged mother cells. We find that combining calorie restriction with either of these genetic interventions dramatically enhances longevity, resulting in the longest-lived yeast strain reported thus far. Further, calorie restriction results in a greater life span extension in cells lacking both Sir2 and Fob1 than in cells where Sir2 is present. These findings indicate that Sir2 and calorie restriction act in parallel pathways to promote longevity in yeast and, perhaps, higher eukaryotes. PMID:15328540

Kaeberlein, Matt; Kirkland, Kathryn T; Fields, Stanley

2004-01-01

107

High sexual signalling rates of young individuals predict extended life span in male Mediterranean fruit flies  

PubMed Central

In a laboratory study, we monitored the lifetime sexual signalling (advertisement) of wild male Mediterranean fruit flies, and we tested the hypothesis that high lifetime intensity of sexual signalling indicates high survival probabilities. Almost all males exhibited signalling and individual signalling rates were highly variable from the beginning of the adults maturity and throughout their life span (average life span 62.3 days). Sexual signalling rates after day 10 (peak maturity) were consistently high until about 1 week before death. There was a positive relationship between daily signalling rates and life span, and an increase in signalling level by one unit over all times was associated with an approximately 50% decrease in mortality rate. Signalling rates early in adult life (day 620) were higher in the longest-lived than in the shortest-lived flies. These results support the hypothesis that intense sexual signalling indicates longer life span. We discuss the importance of age-specific behavioural studies for understanding the evolution of male life histories. PMID:14576929

Katsoyannos, Byron I.; Kouloussis, Nikos A.; Carey, James R.; Muller, Hans-Georg; Zhang, Ying

2008-01-01

108

Polygenic Effects of Common Single-Nucleotide Polymorphisms on Life Span: When Association Meets Causality  

PubMed Central

Abstract Recently we have shown that the human life span is influenced jointly by many common single-nucleotide polymorphisms (SNPs), each with a small individual effect. Here we investigate further the polygenic influence on life span and discuss its possible biological mechanisms. First we identified six sets of prolongevity SNP alleles in the Framingham Heart Study 550K SNPs data, using six different statistical procedures (normal linear, Cox, and logistic regressions; generalized estimation equation; mixed model; gene frequency method). We then estimated joint effects of these SNPs on human survival. We found that alleles in each set show significant additive influence on life span. Twenty-seven SNPs comprised the overlapping set of SNPs that influenced life span, regardless of the statistical procedure. The majority of these SNPs (74%) were within genes, compared to 40% of SNPs in the original 550K set. We then performed a review of current literature on functions of genes closest to these 27 SNPs. The review showed that the respective genes are largely involved in aging, cancer, and brain disorders. We concluded that polygenic effects can explain a substantial portion of genetic influence on life span. Composition of the set of prolongevity alleles depends on the statistical procedure used for the allele selection. At the same time, there is a core set of longevity alleles that are selected with all statistical procedures. Functional relevance of respective genes to aging and major diseases supports causal relationships between the identified SNPs and life span. The fact that genes found in our and other genetic association studies of aging/longevity have similar functions indicates high chances of true positive associations for corresponding genetic variants. PMID:22533364

Wu, Deqing; Arbeev, Konstantin G.

2012-01-01

109

Establishment of life-span extended bovine fibroblast cells carrying the characterization of primary cells.  

PubMed

Although primary bovine embryonic fibroblast (BEF) cells have previously been used as nucleus-donors for nuclear transfer (NT), it has now been proposed to use BEF cells to generate cloned cows that were genetically modified by transgenic or a knock-out system. A major limitation to gene targeting somatic cells, however, is the overall life-span of the cell. In this study, we first examined in vitro life-span of primary BEF cells. Primary BEF cells were found to be replicative senescent at passage 10th-12th, similar to primary murine embryonic fibroblast cells. To overcome this short in vitro life-span, we have optimized culture conditions to extend the life-span and determined growth characteristics of BEF cell lines. Two life-span extended BEF cell lines (designated CGFR -BO-1 and CGFR-BO-2) were shown to grow much faster than their parental primary counterparts. Both cell lines did not display any potential for abnormal growth such as foci formations in either soft-agar or confluent culture condition. In cloning experiments using these cell lines as a nuclear donor, the reconstructed karyoblasts underwent apoptosis, reprogramming and development in the blastocyst stage, at a similar frequency to those observed with parental as well as adult primary fibroblasts. Furthermore, these cell lines targeted with green fluorescence protein (GFP) were successfully transduced, selected and reprogrammed by NT to develop into a blastocyst stage with GFP expression. Our results suggested methods to extend life-span of donor cells with tremendous implications for the genetic engineering of bovine fibroblast cells. PMID:15529005

You, Seungkwon; Heo, Minhee; Moon, Jai-Hee; Kim, Sung-Chan; Kwak, Sungwook; Yoon, Du-Hak; Jin, Dongil; Hong, Ki-Chang; Foster, Douglas N; Choi, Yun-Jaie; Kim, Hyunggee

2004-10-31

110

Effect of different fetal bovine serum concentrations on the replicative life span of cultured chick cells  

Microsoft Academic Search

SummaryThe effect of Eagle's minimal essential medium, containing different fetal bovine serum (FBS) concentrations, on the proliferation\\u000a and replicative life span of cultured chick cells has been studied. Our results showed that the rate of chick cell proliferation\\u000a and the cell density at stationary phase increased as a function of serum concentration between 5 and 30% FBS. The replicative\\u000a life

Jon M. Ryan

1979-01-01

111

Service Learning in Life-Span Developmental Psychology: Higher Exam Scores and Increased Empathy  

ERIC Educational Resources Information Center

This article describes research conducted to evaluate the impact of service learning on exam scores and emotional empathy in a life-span development course. Service learning was 1 of 3 project options offered in the course; others included an interview project and a research paper. With the exception of the first exam, scores were significantly

Lundy, Brenda L.

2007-01-01

112

Theory and Method in Life-Span Development Psychology Implications for Child Development.  

ERIC Educational Resources Information Center

This paper elucidates the implications of life-span developmental psychology for theory and method in the field of child development. Emphasis is given to three theoretical issues: (1) historical-evolutionary versus ontogenetic components of change, (2) the role of chronological age, and (3) continuity versus discontinuity in the description and

Stein, Aletha H.; Baltes, Paul B.

113

Skill Learning as a Concept in Life-Span Developmental Psychology: An Action Theoretic Analysis.  

ERIC Educational Resources Information Center

An action theoretic account of skill learning and skill use is offered as a useful heuristic for life-span developmental psychology. The version presented is one that is particularly prominent in industrial psychology in the German-speaking countries. (Author/RH)

Frese, M.; Stewart, J.

1984-01-01

114

Religious Faith across the Life Span: Implications for Counseling and Research.  

ERIC Educational Resources Information Center

Contends that psychologists can benefit by understanding the religious development of religious clients. Reviews theories of religious development and research on a variety of issues involving religion over the life span. Investigates implications of theory and research on religious involvement in therapy and identifies important questions for

Worthington, Everett L., Jr.

1989-01-01

115

Life span effects of Hypericum perforatum extracts on Caenorhabditis elegans under heat stress  

PubMed Central

Background: The beneficial effects of antioxidants in plants are mainly extrapolated from in vitro studies or short-term dietary supplementation studies. Due to cost and duration, relatively little is known about whether dietary antioxidants are beneficial in whole animals life span or not. Materials and Methods: To address this question, under heat stress (35C), Hypericum perforatum was extracted with petroleum ether and the nematodes Caenorhabditis elegans exposed to three different extract concentrations (1mg/mL, 0.1mg/mL, 0.01mg/mL) of H. perforatum. Results: We report that Hypericum perforatum extracts did not increase life span and slow aging related increase in C. elegans. Moreover, one fraction (1mg/mL) increased declines of C. elegans life span and thermotolerance. Conclusion: Given this mounting evidence for life span role of H. perforatum in the presence of heat stress in vivo, the question whether H. perforatum acts as a prooxidant or an antioxidant in vivo under heat stress arises. PMID:24082638

K?l?cgun, Hasan; Goksen, Gulden

2012-01-01

116

Relationship between heat shock protein 70 expression and life span in Daphnia  

PubMed Central

The longevity of an organism is directly related to its ability to effectively cope with cellular stress. Heat shock response (HSR) protects the cells against accumulation of damaged proteins after exposure to elevated temperatures and also in ageing cells. To understand the role of Hsp70 in regulating life span of Daphnia, we examined the expression of Hsp70 in two ecotypes that exhibit strikingly different life spans. D. pulicaria, the long lived ecotype, showed a robust Hsp70 induction as compared to the shorter lived D. pulex. Interestingly, the short-lived D. pulex isolates showed no induction of Hsp70 at the mid point in their life span. In contrast to this, the long-lived D. pulicaria continued to induce Hsp70 expression at an equivalent age. We further show that the Hsp70 expression was induced at transcriptional level in response to heat shock. The transcription factor responsible for Hsp70 induction, heat shock factor-1 (HSF-1), although present in aged organisms did not exhibit DNA-binding capability. Thus, the decline of Hsp70 induction in old organisms could be attributed to a decline in HSF-1s DNA-binding activity. These results for the first time, present a molecular analysis of the relationship between HSR and life span in Daphnia. PMID:24814302

Schumpert, Charles; Handy, Indhira; Dudycha, Jeffry L.; Patel, Rekha C.

2014-01-01

117

Does Having Children Extend Life Span? A Genealogical Study of Parity and Longevity in the Amish  

Microsoft Academic Search

Background. The relationship between parity and life span is uncertain, with evidence of both positive and negative relationships being reported previously. We evaluated this issue by using genealogical data from an Old Order Amish community in Lancaster, Pennsylvania, a population characterized by large nuclear families, homogeneous lifestyle, and extensive genealogical records. Methods. The analysis was restricted to the set of

Patrick F. McArdle; Toni I. Pollin; Jeffrey R. O'Connell; John D. Sorkin; Richa Agarwala; Alejandro A. Schaffer; Elizabeth A. Streeten; Terri M. King; Alan R. Shuldiner; Braxton D. Mitchell

2006-01-01

118

Changes in Posed Facial Expression of Emotion Across the Adult Life Span  

Microsoft Academic Search

The purpose of this study was to examine changes in the facial expression of emotion across the adult life span. Two positive and two negative emotional expressions were posed by 30 young (21 to 39 years), 30 middle-aged (40 to 59 years), and 30 older (60 to 81 years) healthy, right-handed women. Photographs of the four emotional expressions were rated

Joan C. Borod; Sandra A. Yecker; Adam M. Brickman; Caridad R. Moreno; Martin Sliwinski; Nancy S. Foldi; Murray Alpert; Joan Welkowitz

2004-01-01

119

Human-figure drawing and memory functioning across the adult life span  

Microsoft Academic Search

The main objective was to evaluate changes in the ability to draw the human figure (HFD) across adult life span and to relate these changes to those known to exist in memory function. Healthy adults (1000) from each of 10 five-year cohorts between 35 and 80 years were recruited randomly from a population in northern Sweden. Each participant was administered

Kjerstin Ericsson; Bengt Winblad; Lars-Gran Nilsson

2001-01-01

120

Extension of Cell Life-Span and Telomere Length in Animals Cloned from Senescent Somatic Cells  

Microsoft Academic Search

The potential of cloning depends in part on whether the procedure can reverse cellular aging and restore somatic cells to a phenotypically youthful state. Here, we report the birth of six healthy cloned calves derived from populations of senescent donor somatic cells. Nuclear transfer extended the replicative life-span of senescent cells (zero to four population doublings remaining) to greater than

Robert P. Lanza; Jose B. Cibelli; Catherine Blackwell; Vincent J. Cristofalo; Mary Kay Francis; Gabriela M. Baerlocher; Jennifer Mak; Michael Schertzer; Elizabeth A. Chavez; Nancy Sawyer; Peter M. Lansdorp; Michael D. West

2000-01-01

121

Cancer risk among atomic bomb survivors. The RERF Life Span Study. Radiation Effects Research Foundation  

Microsoft Academic Search

This article summarizes the risk of cancer among the survivors of the atomic bombing of Hiroshima and Nagasaki. We focus primarily on the risk of death from cancer among individuals in the Life Span Study sample of the Radiation Effects Research Foundation from 1950 through 1985 based on recently revised dosimetry procedures. We report the risk of cancer other than

Y. Shimizu; W. J. Schull; H. Kato

1990-01-01

122

Life span and biomass allocation of stunted black spruce clones in the subarctic environment  

Microsoft Academic Search

Summary 1 Slow growth, maintenance of a high leaf:wood ratio and adoption of a clonal growth habit, more than size per se, may increase the life span in trees species. The longevity of black spruce (Picea mariana (Mill.) BSP.) is increased from 200 to 300 years, when it grows as a clonal shrub. 2 We measured the surface area and

Marie-Jose Laberge; Serge Payette; Jean Bousquet

2000-01-01

123

The Use of Digital Technologies across the Adult Life Span in Distance Education  

ERIC Educational Resources Information Center

In June 2010, a survey was carried out to explore access to digital technology, attitudes to digital technology and approaches to studying across the adult life span in students taking courses with the UK Open University. In total, 7000 people were surveyed, of whom more than 4000 responded. Nearly all these students had access to a computer and

Jelfs, Anne; Richardson, John T. E.

2013-01-01

124

Cultural Variation in Verbal Versus Spatial Neuropsychological Function Across the Life Span  

Microsoft Academic Search

Established culture-invariant measures are needed for cross-cultural assessment of verbal and visuospatial speed of processing and working memory across the life span. In this study, 32 younger and 32 older adults from China and from the United States were administered numerically based and spatially based measures of speed of processing and working memory. Chinese superiority on the numerically based tasks

Trey Hedden; Denise C. Park; Richard Nisbett; Li-Jun Ji; Qicheng Jing; Shulan Jiao

2002-01-01

125

Psychopathology in Williams Syndrome: The Effect of Individual Differences across the Life Span  

ERIC Educational Resources Information Center

This research aimed to comprehensively explore psychopathology in Williams syndrome (WS) across the life span and evaluate the relationship between psychopathology and age category (child or adult), gender, and cognitive ability. The parents of 50 participants with WS, ages 6-50 years, were interviewed using the Schedule for Affective Disorders

Dodd, Helen F.; Porter, Melanie A.

2009-01-01

126

Global Self-Esteem Across the Life Span Richard W. Robins, Kali H. Trzesniewski,  

E-print Network

life span. Two decades ago, Wylie (1979) conducted an extensive review of the self-esteem literature Wylie's conclusion (e.g., McCarthy & Hoge, 1982; O'Malley & Bachman, 1983; Rosenberg, 1986), the debates comprehensive reviews of the existing liter- ature were conducted at least a decade ago (e.g., Demo, 1992; Wylie

Pillow, Jonathan

127

Age, growth and size interact with stress to determine life span and mortality  

PubMed Central

Individuals in a large experimental field population, of the short-lived perennial species Plantago lanceolata, were followed to determine the sources of variation that influence mortality and life span. The design included multiple age groups with initially similar genetic structure, which made it possible to separate age effects from period effects and to identify the genetic component to variation in life span. During a period of stress, individuals of all ages showed parallel increases in mortality but different cohorts experienced this period of high mortality at different ages. This then influenced the distribution of life spans across cohorts. Age and size-age interactions influenced mortality during the period of stress. Smaller individuals died but only if they were old. Additionally, growth and age interacted with stress such that older individuals had negative growth and high mortality whereas younger individuals had positive growth and relatively lower mortality during stress. The results of this study show that it is not simply the environment that can have a major impact on demography in natural populations, rather, age, size and growth can interact with the environment to influence mortality and life span when the environment is stressful. PMID:22664575

Roach, Deborah Ann

2012-01-01

128

Extending the Human Life Span: An Exploratory Study of Pro- and Anti-Longevity Attitudes  

ERIC Educational Resources Information Center

Successful efforts by biologists to substantially increase the life span of non-human animals has raised the possibility of extrapolation to humans, which in turn has given rise to bioethical argumentation, pro and con. The present study converts these arguments into pro- and anti-longevity items on a questionnaire and examines the structure and

Kogan, Nathan; Tucker, Jennifer; Porter, Matthew

2011-01-01

129

COMPARISONS OF STRUCTURE AND LIFE SPAN IN ROOTS AND LEAVES AMONG TEMPERATE TREES  

Microsoft Academic Search

Global data sets provide strong evidence of convergence for leaf structure with leaf longevity such that species having thick leaves, low specific leaf area, low mass-based nitrogen concentrations, and low photosynthetic rates typically exhibit long leaf life span. Leaf longevity and corresponding leaf structure have also been widely linked to plant potential growth rate, plant competition, and nutrient cycling. We

Jennifer M. Withington; Peter B. Reich; Jacek Oleksyn; David M. Eissenstat

2006-01-01

130

Effect of habitat preference on frond life span in three Cyathea tree ferns  

NASA Astrophysics Data System (ADS)

It has been reported that plants living in various geographical areas had different physiological forms, as factors of microenvironment have strong impacts on physiological characters. However, the physiological characters of fronds have been scarcely reported in ferns. In this study, we investigated physiological differences in response to the habitat preference in the three tree ferns in northeast Taiwan, Cyathea lepifera, C. spinulosa, and C. podophylla, prefer to open site, edge of forest, and interior forest, respectively. The canopy openness above the individuals of C. lepifera, C. spinulosa and C. podophylla were 29.2 14.10 , 7.0 3.07 and 5.0 2.24 %, respectively. Among three species, C. podophylla had the longest frond life span (13.0 4.12 months) than the two others (C. lepifera (6.8 1.29 months) and C. spinulosa (7.3 1.35 months). Our result supported the general patterns that shade intolerant species have a shorter leaf life span than shade tolerant species. The maximum net CO2 assimilation of C. lepifera, C. spinulosa and C. podophylla were 11.46 1.34, 8.27 0.69, and 6.34 0.54 ?mol CO2 m-2 s-1, respectively. As well, C. lepifera had the highest photosynthetic light saturation point (LSP), while C. podophylla had the lowest LSP among these three tree ferns. These suggested that C. lepifera could be more efficient for capturing and utilizing light resources under the larger canopy openness condition than the other two species. We also found that frond C : N ratio were positively correlated with frond life span among species. C. podophylla, with the longest frond life span, had the highest frond C : N ratio (22.17 1.95), which was followed by C. spinulosa (18.58 1.37) and C. lepifera (18.68 2.63) with shorter frond life span. The results were consistent to the theory that the fronds and leaves of shade intolerant species have high photosynthetic abilities with low C : N ratio. Key words: Canopy openness, frond life span, tree fern, Cyathea, frond C : N ratio

Chiu, Tzu Yun; Wang, Hsiang Hua; Lun Kuo, Yao; Kume, Tomonori

2013-04-01

131

Causes and consequences of variation in conifer leaf life-span  

SciTech Connect

Species with mutually supporting traits, such as high N{sub mass}, SLA, and A{sub mass}, and short leaf life-span, tend to inhabit either generally resource-rich environments or spatial and/or temporal microhabitats that are resource-rich in otherwise more limited habitats (e.g., {open_quotes}precipitation{close_quotes} ephemerals in warm deserts or spring ephemerals in the understory of temperate deciduous forests). In contrast, species with long leaf life-span often support foliage with low SLA, N{sub mass}, and A{sub mass}, and often grow in low-temperature limited, dry, and/or nutrient-poor environments. The contrast between evergreen and deciduous species, and the implications that emerge from such comparisons, can be considered a paradigm of modern ecological theory. However, based on the results of Reich et al. (1992) and Gower et al. (1993), coniferous species with foliage that persists for 9-10 years are likely to assimilate and allocate carbon and nutrients differently than other evergreen conifers that retain foliage for 2-3 years. Thus, attempts to contrast ecophysiological or ecosystem characteristics of evergreen versus deciduous life forms may be misleading, and pronounced differences among evergreen conifers may be ignored. Clearly, the deciduous-evergreen contrast, although useful in several ways, should be viewed from the broader perspective of a gradient in leaf life-span.

Reich, P.B.; Koike, T.; Gower, S.T.; Schoettle, A.W.

1995-07-01

132

Requirement of NAD and SIR2 for Life-Span Extension by Calorie Restriction in Saccharomyces cerevisiae  

Microsoft Academic Search

Calorie restriction extends life-span in a wide variety of organisms. Although it has been suggested that calorie restriction may work by reducing the levels of reactive oxygen species produced during respiration, the mechanism by which this regimen slows aging is uncertain. Here, we mimicked calorie restriction in yeast by physiological or genetic means and showed a substantial extension in life-span.

Su-Ju Lin; Pierre-Antoine Defossez; Leonard Guarente

2000-01-01

133

Muscles of mice deficient in -sarcoglycan maintain large masses and near control force values throughout the life span  

E-print Network

of the pathology and the effects on muscle structure and function throughout the life span are not known. Thus throughout the life span Christina M. Consolino,1,2 Franck Duclos,3 Jane Lee,3 Roger A. Williamson,4 Kevin P Department of Obstetrics and Gynecology, University of Iowa, Iowa City, Iowa Submitted 27 December 2004

Campbell, Kevin P.

134

Dependence of the life span of the honeybee ( Apis mellifica ) upon flight performance and energy consumption  

Microsoft Academic Search

The life span of worker-honeybees is determined by the duration of the hive-period and of the foraging period (Figs. 1,2). The duration of the forgaing period is regulated in the following way: Total flight performance of the individual bee seems to be fixed. Daily flight performance strongly affects total flight duration. High daily flight performance decreases maximal flight duration and

Angelika Neukirch

1982-01-01

135

Body Image Across the Life Span in Adult Women: The Role of Self-Objectification  

Microsoft Academic Search

This study aimed to investigate women's body image across the entire life span from within the theoretical perspective provided by objectification theory (B. L. Fredrickson & T.-A. Roberts, 1997). In a cross-sectional study, a sample of 322 women ranging in age from 20 to 84 years completed a questionnaire measuring body dissatisfaction, self-objectification, and its proposed consequences. Although body dissatisfaction

Marika Tiggemann; Jessica E. Lynch

2001-01-01

136

CD4 memory T cell levels predict life span in genetically heterogeneous mice  

Microsoft Academic Search

Aging leads to changes in the relative proportions of several functionally distinct T cell sub- sets, including increases in the proportions of mem- ory cells in the CD4 and CD8 subsets and in the proportion of T cells expressing the multiple-drug resistance pump P-glycoprotein. To see whether in- dividual differences in T cell subset levels predict life span, we measured

RICHARD A. MILLER; CLARENCE CHRISP; ANDRZEJ GALECKV

137

Cognitive Creative Abilities and Self-Esteem across the Adult Life-Span  

Microsoft Academic Search

The purpose of this study was to explore the relationship between divergent thinking and self-esteem in age groups across the adult life-span. A total of 218 subjects ranging in age from 18 to 84 years responded to a personal data inventory, a self-esteem measure, and a taped auditory free-response exercise in divergent thinking. Scores were obtained for fluency, flexibility, and

Gail A. Jaquish; Richard E. Ripple

1981-01-01

138

[Child and adolescent psychiatry and adult psychiatry: cooperation over the life span].  

PubMed

Child and adolescent psychiatry and adult psychiatry have important common research and working fields, in particular the diagnostics and treatment of disorders with onset in childhood or adolescence and persistence over the life span. Other important aspects in common are the treatment of families (e.g., special wards for children and their parents, children of mentally ill parents), in medical teaching and postgraduate education as well as representative functions in societal and political issues. PMID:20842340

Herpertz-Dahlmann, B; Herpertz, S

2010-11-01

139

Transient Expression of Human Telomerase Extends the Life Span of Normal Human Fibroblasts  

Microsoft Academic Search

We utilized the Cre\\/lox recombination system to transiently express the catalytic subunit of telomerase (hTERT) in normal diploid foreskin fibroblasts (BJ cells). A retroviral construct containing an hTERT cDNA, flanked by loxP-sites was introduced into near senescent BJ cells (population doubling 85). At population doubling (PD) 92, which exceeds the typical life span of these cells, we excised the gene

Susanne Steinert; Jerry W. Shay; Woodring E. Wright

2000-01-01

140

Leaf life span spectrum of tropical woody seedlings: effects of light and ontogeny and consequences for survival  

PubMed Central

Background and Aims Leaf life span is widely recognized as a key life history trait associated with herbivory resistance, but rigorous comparative data are rare for seedlings. The goal of this study was to examine how light environment affects leaf life span, and how ontogenetic development during the first year may influence leaf fracture toughness, lamina density and stem density that are relevant for herbivory resistance, leaf life span and seedling survival. Methods Data from three experiments encompassing 104 neotropical woody species were combined. Leaf life span, lamina and vein fracture toughness, leaf and stem tissue density and seedling survival were quantified for the first-year seedlings at standardized ontogenetic stages in shade houses and common gardens established in gaps and shaded understorey in a moist tropical forest in Panama. Mortality of naturally recruited seedlings till 1 year later was quantified in 800 1-m2 plots from 1994 to 2011. Key Results Median leaf life span ranged widely among species, always greater in shade (ranging from 151 to >1790 d in the understorey and shade houses) than in gaps (115867 d), but with strong correlation between gaps and shade. Leaf and stem tissue density increased with seedling age, whereas leaf fracture toughness showed only a weak increase. All these traits were positively correlated with leaf life span. Leaf life span and stem density were negatively correlated with seedling mortality in shade, while gap mortality showed no correlation with these traits. Conclusions The wide spectrum of leaf life span and associated functional traits reflects variation in shade tolerance of first-year seedlings among coexisting trees, shrubs and lianas in this neotropical forest. High leaf tissue density is important in enhancing leaf toughness, a known physical defence, and leaf life span. Both seedling leaf life span and stem density should be considered as key functional traits that contribute to seedling survival in tropical forest understoreys. PMID:23532047

Kitajima, Kaoru; Cordero, Roberto A.; Wright, S. Joseph

2013-01-01

141

Two-carbon metabolites, polyphenols and vitamins influence yeast chronological life span in winemaking conditions  

PubMed Central

Background Viability in a non dividing state is referred to as chronological life span (CLS). Most grape juice fermentation happens when Saccharomyces cerevisiae yeast cells have stopped dividing; therefore, CLS is an important factor toward winemaking success. Results We have studied both the physical and chemical determinants influencing yeast CLS. Low pH and heat shorten the maximum wine yeast life span, while hyperosmotic shock extends it. Ethanol plays an important negative role in aging under winemaking conditions, but additional metabolites produced by fermentative metabolism, such as acetaldehyde and acetate, have also a strong impact on longevity. Grape polyphenols quercetin and resveratrol have negative impacts on CLS under winemaking conditions, an unexpected behavior for these potential anti-oxidants. We observed that quercetin inhibits alcohol and aldehyde dehydrogenase activities, and that resveratrol performs a pro-oxidant role during grape juice fermentation. Vitamins nicotinic acid and nicotinamide are precursors of NAD+, and their addition reduces mean longevity during fermentation, suggesting a metabolic unbalance negative for CLS. Moreover, vitamin mix supplementation at the end of fermentation shortens CLS and enhances cell lysis, while amino acids increase life span. Conclusions Wine S. cerevisiae strains are able to sense changes in the environmental conditions and adapt their longevity to them. Yeast death is influenced by the conditions present at the end of wine fermentation, particularly by the concentration of two-carbon metabolites produced by the fermentative metabolism, such as ethanol, acetic acid and acetaldehyde, and also by the grape juice composition, particularly its vitamin content. PMID:22873488

2012-01-01

142

Life span and tumor incidence in rats receiving postradiation treatment with ATP-AET-mexamine mixture  

SciTech Connect

Rat females were exposed to a single 4.0-Gy ..gamma..-ray dose and treated postradiation with a mixture of ATP-AET-mexamine at daily doses of 24, 12, and 3 mg/kg body wt, respectively, in drinking water throughout the period of their survival. With the radiation dose used, life shortening appeared primarily attributable to nonstochastic effects. The mixture of chemical protectors failed to show modification of long-term radiation effects with regard to either life span or tumor incidence.

Benova, D.K.; Kiradzhiev, G.D.; Troitskaya, M.N.; Anisimov, V.N.

1985-01-01

143

Life Satisfaction, Self-Esteem, and Subjective Age in Women across the Life Span  

ERIC Educational Resources Information Center

A study of 320 women, ages 21 to 69, explored the relations among relationship status, subjective age, self-esteem, and life satisfaction. Women in married or partnered relationships had higher levels of life satisfaction than did single women. Women in their 30s and 40s had significantly lower levels of life satisfaction than did other age

Borzumato-Gainey, Christine; Kennedy, Alison; McCabe, Beth; Degges-White, Suzanne

2009-01-01

144

Shorter Life Span of Microorganisms and Plants as a Consequence of Shielded Magnetic Environment  

NASA Astrophysics Data System (ADS)

The geomagnetic field is an essential environmental factor for life and health on this planet. In order to survey how magnetic fields affect the life span and the nitrogenase (an iron-sulphur enzyme) activity of Azotobacter chroococcum as well as the life span, the main organic synthesis and the water balance of plants (22 species), the biological tests were incubated under shielded magnetic field and also in normal geo-magnetic environment. The shielding level was about 10-6 of the terrestrial magnetic field.Life cycles of all organisms require the co-ordinated control of a complex set of interlocked physiological processes and metabolic pathways. Such processes are likely to be regulated by a large number of genes. Our researches suggest that the main point in biological structures, which seems to be affected by the low magnetic environment, is the water molecule. Magnetic field induces a molecular alignment. Under shielded conditions, unstructured water molecules with fewer hydrogen bonds, which are producing a more reactive environment, are occurring. As compared to control, the life span of both microorganisms and plants was shorter in shielded environment. A higher nitrogenase affinity for the substrate was recorded in normal geo-magnetic field compared to low magnetic field. The synthesis of carbohydrates, lipids, proteins and enzymes was modified under experimental conditions. The stomatal conductance was higher between 158 and 300% in shielded environment indicating an important water loss from the plant cells.Our results support the idea that the shielded magnetic environment induces different reactions depending on the time of exposure and on the main metabolic pathways of the cells.

Dobrota, C.; Piso, I. M.; Bathory, D.

145

Dead or alive: deformed wing virus and Varroa destructor reduce the life span of winter honeybees.  

PubMed

Elevated winter losses of managed honeybee colonies are a major concern, but the underlying mechanisms remain controversial. Among the suspects are the parasitic mite Varroa destructor, the microsporidian Nosema ceranae, and associated viruses. Here we hypothesize that pathogens reduce the life expectancy of winter bees, thereby constituting a proximate mechanism for colony losses. A monitoring of colonies was performed over 6 months in Switzerland from summer 2007 to winter 2007/2008. Individual dead workers were collected daily and quantitatively analyzed for deformed wing virus (DWV), acute bee paralysis virus (ABPV), N. ceranae, and expression levels of the vitellogenin gene as a biomarker for honeybee longevity. Workers from colonies that failed to survive winter had a reduced life span beginning in late fall, were more likely to be infected with DWV, and had higher DWV loads. Colony levels of infection with the parasitic mite Varroa destructor and individual infections with DWV were also associated with reduced honeybee life expectancy. In sharp contrast, the level of N. ceranae infection was not correlated with longevity. In addition, vitellogenin gene expression was significantly positively correlated with ABPV and N. ceranae loads. The findings strongly suggest that V. destructor and DWV (but neither N. ceranae nor ABPV) reduce the life span of winter bees, thereby constituting a parsimonious possible mechanism for honeybee colony losses. PMID:22179240

Dainat, Benjamin; Evans, Jay D; Chen, Yan Ping; Gauthier, Laurent; Neumann, Peter

2012-02-01

146

Provenance, life span, and phylogeny do not affect grass species' responses to nitrogen and phosphorus.  

PubMed

Successful conservation management requires an understanding of how species respond to intervention. Native and exotic species may respond differently to management interventions due to differences arising directly from their origin (i.e., provenance) or indirectly due to biased representations of different life history types (e.g., annual vs. perennial life span) or phylogenetic lineages among provenance (i.e., native or exotic origin) groups. Thus, selection of a successful management regime requires knowledge of the life history and provenance-bias in the local flora and an understanding of the interplay between species characteristics across existing environmental gradients in the landscape. Here we tested whether provenance, phylogeny, and life span interact to determine species distributions along natural gradients of soil chemistry (e.g., soil nitrogen and phosphorus) in 10 upland prairie sites along a 600-km latitudinal transect running from southern Vancouver Island in British Columbia, Canada, to the Willamette Valley in Oregon, USA. We found that soil nitrate, phosphorus, and pH exerted strong control over community composition. However, species distributions along environmental gradients were unrelated to provenance, life span, or phylogenetic groupings. We then used a greenhouse experiment to more precisely measure the response of common grass species to nitrogen and phosphorus supply. As with the field data, species responses to nutrient additions did not vary as a function of provenance, life span, or phylogeny. Native and exotic species differed strongly in the relationship between greenhouse-measured tolerance of low nutrients and field abundance. Native species with the greatest ability to maintain biomass production at low nutrient supply rates were most abundant in field surveys, as predicted by resource competition theory. In contrast, there was no relationship between exotic-species biomass at low nutrient levels and field abundance. The implications of these findings for management of invasive species are substantial in that they overturn a general belief that reduction of nutrient supplies favors native species. The idiosyncratic nature of species response to nutrients in this study suggests that manipulation of nutrient supplies is unlikely to alter the overall balance between native and exotic species, although it may well be useful to control specific exotic species. PMID:21939049

Seabloom, Eric W; Benfield, Cara D; Borer, Elizabeth T; Stanley, Amanda G; Kaye, Thomas N; Dunwiddie, Peter W

2011-09-01

147

Marital, reproductive, and educational behaviors covary with life expectancy.  

PubMed

Theories of "life history evolution" suggest that individuals might adjust the timing of marriage and reproduction, as well as their propensity to terminate a marriage or pregnancy and invest in skill development, in response to indicators of the locally prevailing level of life expectancy. In particular, such theories generate the hypothesis that foreshortened time horizons lead to hastened reproduction and marriage whereas lengthier time horizons increase the likelihood of reproductive and marital termination and lead to greater investment in education. Here, I show that the scheduling and occurrence of marital and reproductive behavior (including both initiation and termination), as well as levels of educational attainment and investment, covary with life expectancy, even after controlling for the effects of affluence. In analyses of variation in marital, reproductive, and educational behaviors at two jurisdictional levels in Canada, life expectancy was positively correlated with patterns of age-specific fertility, age at first marriage, divorce, abortion, conferral of high school and higher education degrees (with the exception of the trades) and mean number of years of schooling. The large and highly consistent relationships observed between life expectancy and the behaviors under investigation suggest that these associations may be mediated by individual "perceptions" of life expectancy, though more research is needed before conclusions can be firmly reached. PMID:22484517

Krupp, Daniel Brian

2012-12-01

148

RESEARCH ARTICLE Demography, Female Life History, and Reproductive  

E-print Network

RESEARCH ARTICLE Demography, Female Life History, and Reproductive Profiles Among the Chimpanzees%). Fifty percent of Mahale chimpanzees died before weaning. The median ages of female life history the age at immigration to that at first birth. Female fecundity was highest between 20 and 35 yr of age

149

Personality development across the life span: longitudinal analyses with a national sample from Germany.  

PubMed

Longitudinal data from a national sample of Germans (N = 20,434) were used to evaluate stability and change in the Big Five personality traits. Participants completed a brief measure of personality twice, 4 years apart. Structural equation modeling techniques were used to establish measurement invariance over time and across age groups. Substantive questions about differential (or rank-order) and mean-level stability and change were then evaluated. Results showed that differential stability was relatively strong among all age groups but that it increased among young adults, peaked in later life, and then declined among the oldest old. Patterns of mean-level change showed that Extraversion and Openness declined over the life span, whereas Agreeableness increased. Mean levels of Conscientiousness increased among young adults and then decreased among older adults. Trajectories for Neuroticism were relatively flat, with slight increases during middle age and a slight decline in late life. PMID:21707197

Lucas, Richard E; Donnellan, M Brent

2011-10-01

150

Glucocorticoids Act Directly on Osteoclasts to Increase Their Life Span and Reduce Bone Density  

PubMed Central

Glucocorticoid administration to mice results in a rapid loss of bone mineral density due to an imbalance in osteoblast and osteoclast numbers. Whereas excess glucocorticoids reduce both osteoblast and osteoclast precursors, cancellous osteoclast number surprisingly does not decrease as does osteoblast number, presumably due to the ability of glucocorticoids to promote osteoclast life span. Whether glucocorticoids act directly on osteoclasts in vivo to promote their life span and whether this contributes to the rapid loss of bone with glucocorticoid excess remains unknown. To determine the direct effects of glucocorticoids on osteoclasts in vivo, we expressed 11?-hydroxysteroid dehydrogenase type 2, an enzyme that inactivates glucocorticoids, specifically in the osteoclasts of transgenic mice using the tartrate-resistant acid phosphatase promoter. Bone mass, geometry, and histomorphometry were similar in untreated wild-type and transgenic animals. Glucocorticoid administration for 7 d caused equivalent increases in cancellous osteoblast apoptosis, and equivalent decreases in osteoblasts, osteoid, and bone formation, in wild-type and transgenic mice. In contrast, glucocorticoids stimulated expression of the mRNA for calcitonin receptor, an osteoclast product, in wild-type but not transgenic mice. Consistent with the previous finding that glucocorticoids decrease osteoclast precursors and prolong osteoclast life span, glucocorticoids decreased cancellous osteoclast number in the transgenic mice but not wild-type mice. In accord with this decrease in osteoclast number, the loss of bone density observed in wild-type mice was strikingly prevented in trans-genic mice. These results demonstrate for the first time that the early, rapid loss of bone caused by glucocorticoid excess results from direct actions on osteoclasts. PMID:16935844

Jia, D.; O'Brien, C. A.; Stewart, S. A.; Manolagas, S. C.; Weinstein, R. S.

2007-01-01

151

[Effect of epitalon and melatonin on life span and spontaneous carcinogenesis in senescence accelerated mice (SAM)].  

PubMed

Female senescence accelerated mice SAMP-1. (prone) and SAMR-1 (resistant) were exposed 5 times a week monthly to melatonin (with drinking water 20mg/ml during the night hours) or to s.c. injections of epitalon (Ala-Glu-Asp-Gly) at a single dose 1mkg/mouse. Control mice were intact or exposed to injection of 0.1 ml normal saline. The body weight and temperature, food consumption, estrous function were monitored regularly. The life span and tumor incidence were evaluated as well. As age advanced, the weight increased whereas food consumption and body temperature did not change. There was no significant substrain difference in these parameters. Exposure to melatonin or epitalon also failed to influence those indices. As age advanced, the incidence of irregular estrous cycles increased both in SAMP-1 and SAMR-1, whereas the treatment with both melatonin and epitalon prevented such disturbances. SAMP-1 revealed some features of accelerated aging as compared to SAMR-1. The mean life span of the 10% of the last survivors among treated SAMP-1 was shorter than that of SAMR-1, aging rate increased and mortality doubling time decreased. There was a direct correlation between body mass of the two substrains at the age of 3 and 12 months matched by body mass increase and longer life span. Melatonin or epitalon treatment was followed by longer mean and maximum survival in the 10% of the last survivors among SAMP-1. Melatonin involved decreased aging rate and increased mortality doubling time. Malignant lymphomas predominated in SAM without any significant difference in frequency between the substrains. While melatonin failed to influence tumor incidence or term of detection in SAMP-1, neither did epitalon affect frequency. However, it was followed by longer survival in tumor-free animals. No link between melatonin or epitalon treatment, on the one hand, and carcinogenesis, on the other, was reported in SAMR-1. PMID:15909815

Anisimov, V N; Popovich, I G; Zabezhinski?, M A; Rozenfel'd, S V; Khavinson, V Kh; Semenchenko, A V; Iashin, A I

2005-01-01

152

Caffeine extends life span, improves healthspan, and delays age-associated pathology in Caenorhabditis elegans  

PubMed Central

Background The longevity of an organism is influenced by both genetic and environmental factors. With respect to genetic factors, a significant effort is being made to identify pharmacological agents that extend life span by targeting pathways with a defined role in the aging process. On the environmental side, the molecular mechanisms responsible for the positive influence of interventions such as dietary restriction are being explored. The environment experienced by humans in modern societies already contains countless compounds that may influence longevity. Understanding the role played by common compounds that substantially affect the aging process will be critical for predicting and interpreting the outcome of introducing new interventions. Caffeine is the most widely used psychoactive drug worldwide. Prior studies in flies, worms, and mice indicate that caffeine may positively impact age-associated neurodegenerative pathology, such as that observed in Alzheimers disease. Results Here we report that caffeine is capable of extending life span and improving healthspan in Caenorhabditis elegans, a finding that is in agreement with a recently published screen looking for FDA-approved compounds capable of extending worm life span. Life span extension using caffeine displays epistatic interaction with two known longevity interventions: dietary restriction and reduced insulin signaling. Caffeine treatment also delays pathology in a nematode model of polyglutamine disease. Conclusions The identification of caffeine as a relevant factor in aging and healthspan in worms, combined with prior work in both humans and rodents linking caffeine consumption to reduced risk of age-associated disease, suggests that caffeine may target conserved longevity pathways. Further, it may be important to consider caffeine consumption when developing clinical interventions, particularly those designed to mimic dietary restriction or modulate insulin/IGF-1-like signaling. The positive impact of caffeine on a worm model of polyglutamine disease suggests that chronic caffeine consumption may generally enhance resistance to proteotoxic stress and may be relevant to assessing risk and developing treatments for human diseases like Alzheimers and Huntingtons disease. Future work addressing the relevant targets of caffeine in models of aging and healthspan will help to clarify the underlying mechanisms and potentially identify new molecular targets for disease intervention. PMID:24764514

2012-01-01

153

The ProSeal??? Has a Shorter Life-Span than the Classic??? Laryngeal Mask Airway  

Microsoft Academic Search

We tested the hypothesis that the life-span of the ProSeal laryngeal mask airway (LMA) is shorter than the Classic LMA. We also compared residual cuff vol- umesandchangesinelastanceandpermeabilitywithuse. Sixnewsize4ProSealLMAsand6newsize4Classic LMAs were tested. Each LMA underwent a simulated clinicalusecycleuntilitfailedthepre-usechecktests.The simulatedclinicalusecyclecomprised:i)inflatingthecuff tothemaximumrecommendedvolumefor1h;ii)immer- sion in an enzymatic solution for 3 min; iii) washing the external and internal surfaces; iv) automatic washing for 14 min

Sarah Doneley; Joseph Brimacombe; Christian Keller; Achim von Goedecke

2005-01-01

154

What accounts for the wide variation in life span of genetically identical organisms reared in a constant environment?  

E-print Network

mortal- ity, the individuals display very different life spans. Isogenic populations of the nematode, facilitating the production and maintenance of genetically uniform cultures. In addition, C. elegans has laboratory culture procedures provide exceptionally constant environ- ments. It might be expected

Klingenberg, Christian Peter

155

Genetic Deletion of Nrf2 Promotes Immortalization and Decreases Life Span of Murine Embryonic Fibroblasts  

PubMed Central

Nuclear factor E2related factor-2 (Nrf2) transcription factor is one of the main regulators of intracellular redox balance and a sensor of oxidative and electrophilic stress. Low Nrf2 activity is usually associated with carcinogenesis, but Nrf2 is also considered as an oncogene because it increases survival of transformed cells. Because intracellular redox balance alterations are involved in both senescence and tumorigenesis, we investigated the impact of Nrf2 genetic deletion on cellular immortalization and life span of murine embryonic fibroblasts. We report that Nrf2 genetic deletion promotes immortalization due to an early loss of p53-dependent gene expression. However, compared with control cells, immortalized Nrf2?/? murine embryonic fibroblasts exhibited decreased growth, lower cyclin E levels, and impaired expression of NQO1 and cytochrome b5 reductase. Moreover, SirT1 was also significantly reduced in immortalized Nrf2?/? murine embryonic fibroblasts, and these cells exhibited shorter life span. Our results underscore the dual role of Nrf2 in protection against carcinogenesis and in the delay of cellular aging. PMID:20974733

Jodar, Laura; Mercken, Evi M.; Ariza, Julia; Younts, Caitlin; Gonzalez-Reyes, Jose A.; Alcain, Francisco J.; Buron, Isabel; de Cabo, Rafael

2011-01-01

156

Genetic deletion of Nrf2 promotes immortalization and decreases life span of murine embryonic fibroblasts.  

PubMed

Nuclear factor E2-related factor-2 (Nrf2) transcription factor is one of the main regulators of intracellular redox balance and a sensor of oxidative and electrophilic stress. Low Nrf2 activity is usually associated with carcinogenesis, but Nrf2 is also considered as an oncogene because it increases survival of transformed cells. Because intracellular redox balance alterations are involved in both senescence and tumorigenesis, we investigated the impact of Nrf2 genetic deletion on cellular immortalization and life span of murine embryonic fibroblasts. We report that Nrf2 genetic deletion promotes immortalization due to an early loss of p53-dependent gene expression. However, compared with control cells, immortalized Nrf2-/- murine embryonic fibroblasts exhibited decreased growth, lower cyclin E levels, and impaired expression of NQO1 and cytochrome b? reductase. Moreover, SirT1 was also significantly reduced in immortalized Nrf2-/- murine embryonic fibroblasts, and these cells exhibited shorter life span. Our results underscore the dual role of Nrf2 in protection against carcinogenesis and in the delay of cellular aging. PMID:20974733

Jdar, Laura; Mercken, Evi M; Ariza, Julia; Younts, Caitlin; Gonzlez-Reyes, Jos A; Alcan, Francisco J; Burn, Isabel; de Cabo, Rafael; Villalba, Jos M

2011-03-01

157

Caenorhabditis elegans RNA-processing protein TDP-1 regulates protein homeostasis and life span.  

PubMed

Transactive response DNA-binding protein (TARDBP/TDP-43), a heterogeneous nuclear ribonucleoprotein (hnRNP) with diverse activities, is a common denominator in several neurodegenerative disorders, including amyotrophic lateral sclerosis and frontotemporal lobar degeneration. Orthologs of TDP-43 exist in animals ranging from mammals to invertebrates. Here, we systematically studied mutant Caenorhabditis elegans lacking the nematode TDP-43 ortholog, TDP-1. Heterologous expression of human TDP-43 rescued the defects in C. elegans lacking TDP-1, suggesting their functions are conserved. Although the tdp-1 mutants exhibited deficits in fertility, growth, and locomotion, loss of tdp-1 attenuated defects in several C. elegans models of proteotoxicity. Loss of tdp-1 suppressed defects in transgenic C. elegans expressing TDP-43 or CuZn superoxide dismutase, both of which are associated with proteotoxicity in neurodegenerative diseases. Loss of tdp-1 also reduced defects in mutant animals lacking the heat shock factor HSF-1. Transcriptional profiling demonstrated that the loss of TDP-1 altered expression of genes functioning in RNA processing and protein folding. Furthermore, the absence of tdp-1 extended the life span in C. elegans. The life span extension required a FOXO transcriptional factor DAF-16 but not HSF-1. These results suggest that the C. elegans TDP-1 has a role in the regulation of protein homeostasis and aging. PMID:22232551

Zhang, Tao; Hwang, Ho-Yon; Hao, Haiping; Talbot, Conover; Wang, Jiou

2012-03-01

158

Neonatal hyperoxia causes pulmonary vascular disease and shortens life span in aging mice.  

PubMed

Bronchopulmonary dysplasia is a chronic lung disease observed in premature infants requiring oxygen supplementation and ventilation. Although the use of exogenous surfactant and protective ventilation strategies has improved survival, the long-term pulmonary consequences of neonatal hyperoxia are unknown. Here, we investigate whether neonatal hyperoxia alters pulmonary function in aging mice. By 67 weeks of age, mice exposed to 100% oxygen between postnatal days 1 to 4 showed significantly a shortened life span (56.6% survival, n = 53) compared to siblings exposed to room air as neonates (100% survival, n = 47). Survivors had increased lung compliance and decreased elastance. There was also right ventricular hypertrophy and pathological evidence for pulmonary hypertension, defined by reduction of the distal microvasculature and the presence of numerous dilated arterioles expressing von Willebrand factor and ?-smooth muscle actin. Consistent with recent literature implicating bone morphogenetic protein (BMP) signaling in pulmonary vascular disease, BMP receptors and downstream phospho-Smad1/5/8 were reduced in lungs of aging mice exposed to neonatal oxygen. BMP signaling alterations were not observed in 8-week-old mice. These data suggest that loss of BMP signaling in aged mice exposed to neonatal oxygen is associated with a shortened life span, pulmonary vascular disease, and associated cardiac failure. People exposed to hyperoxia as neonates may be at increased risk for pulmonary hypertension. PMID:21550015

Yee, Min; White, R James; Awad, Hani A; Bates, Wendy A; McGrath-Morrow, Sharon A; O'Reilly, Michael A

2011-06-01

159

Stochastic variation in telomere shortening rate causes heterogeneity of human fibroblast replicative life span.  

PubMed

The replicative life span of human fibroblasts is heterogeneous, with a fraction of cells senescing at every population doubling. To find out whether this heterogeneity is due to premature senescence, i.e. driven by a nontelomeric mechanism, fibroblasts with a senescent phenotype were isolated from growing cultures and clones by flow cytometry. These senescent cells had shorter telomeres than their cycling counterparts at all population doubling levels and both in mass cultures and in individual subclones, indicating heterogeneity in the rate of telomere shortening. Ectopic expression of telomerase stabilized telomere length in the majority of cells and rescued them from early senescence, suggesting a causal role of telomere shortening. Under standard cell culture conditions, there was a minor fraction of cells that showed a senescent phenotype and short telomeres despite active telomerase. This fraction increased under chronic mild oxidative stress, which is known to accelerate telomere shortening. It is possible that even high telomerase activity cannot fully compensate for telomere shortening in all cells. The data show that heterogeneity of the human fibroblast replicative life span can be caused by significant stochastic cell-to-cell variation in telomere shortening. PMID:14963037

Martin-Ruiz, Carmen; Saretzki, Gabriele; Petrie, Joanne; Ladhoff, Juliane; Jeyapalan, Jessie; Wei, Wenyi; Sedivy, John; von Zglinicki, Thomas

2004-04-23

160

Yeast endosulfines control entry into quiescence and chronological life span by inhibiting protein phosphatase 2A.  

PubMed

The TORC1 and PKA protein kinases are central elements of signaling networks that regulate eukaryotic cell proliferation in response to growth factors and/or nutrients. In yeast, attenuation of signaling by these kinases following nitrogen and/or carbon limitation activates the protein kinase Rim15, which orchestrates the initiation of a reversible cellular quiescence program to ensure normal chronological life span. The molecular elements linking Rim15 to distal readouts including the expression of Msn2/4- and Gis1-dependent genes involve the endosulfines Igo1/2. Here, we show that Rim15, analogous to the greatwall kinase in Xenopus, phosphorylates endosulfines to directly inhibit the Cdc55-protein phosphatase 2A (PP2A(Cdc55)). Inhibition of PP2A(Cdc55) preserves Gis1 in a phosphorylated state and consequently promotes its recruitment to and activation of transcription from promoters of specific nutrient-regulated genes. These results close a gap in our perception of and delineate a role for PP2A(Cdc55) in TORC1-/PKA-mediated regulation of quiescence and chronological life span. PMID:23273919

Bontron, Sverine; Jaquenoud, Malika; Vaga, Stefania; Talarek, Nicolas; Bodenmiller, Bernd; Aebersold, Ruedi; De Virgilio, Claudio

2013-01-31

161

Correlation Between Deoxyribonucleic Acid Excision-Repair and Life-Span in a Number of Mammalian Species  

PubMed Central

The ability of fibroblasts to perform unscheduled DNA synthesis (a measure of excision-repair) after UV irradiation was measured radioautographically for seven species at several times after several UV fluences. Both the initial rate and the maximum incorporation of [3H]dThd increased with the life-span of the species (shrew, mouse, rat, hamster, cow, elephant, man). Unscheduled DNA synthesis was approximately proportional to the logarithm of life-span. PMID:4526202

Hart, R. W.; Setlow, R. B.

1974-01-01

162

Reproductive and early life stages pathology - Histopathology workshop report  

USGS Publications Warehouse

Pathology occurring during reproduction and larval development represents an important part of the life cycle of fish, and the diseases that affect eggs and larvae often result in significant losses. However, mortality during this period is frequently ignored or poorly researched as the temptation is to replace the losses rather than investigate the causes. A histopathology workshop organised at the newly refurnished laboratory within the Danish Veterinary School was an opportunity to discuss the pathology of selected diseases associated with Reproductive and Early Life Stages Pathology. Several people also kindly provided reference slides.

Bruno, D. W.; Nowak, B.; Elliott, D. G.

2006-01-01

163

Spermatozoid life-span of two brown seaweeds, Saccharina japonica and Undaria pinnatifida, as measured by fertilization efficiency  

NASA Astrophysics Data System (ADS)

During sexual reproduction of seaweeds, spermatozoid (sperm) discharge is triggered by chemical messengers (pheromones) released by the female gametes. The chemotactic ability of the sperm ensures fertilization success. Using unialgal male and female gametophyte material under designated standard gametogenesis testing (SGT) conditions, the potential life-span of the sperm of two seaweeds, Saccharina japonica and Undaria pinnatifida, was assessed by their ability to fertilize eggs. Results show that within 20-30 min after being discharged, sperm of both species could complete fertilization without an apparent decline in fertilization rate. Although fertilization rate 60-120 min after sperm discharge dropped significantly in both species, some sperm were viable enough to fertilize the eggs. In S. japonica, at 12C, some sperm were able to fertilize eggs up to 12 h after discharge. In both species, egg discharge rates (EDR) in the male and female mixed positive controls were significantly higher than those of all the sperm-testing groups. Doubling the seeded male gametophytes of S. japonica in the SGT tests significantly increased the EDR, further confirming the effect of the presence of the male on the female in terms of facilitating egg discharge from oogonia.

Li, Jing; Pang, Shaojun; Liu, Feng; Shan, Tifeng; Gao, Suqin

2013-07-01

164

Social network changes and life events across the life span: a meta-analysis.  

PubMed

For researchers and practitioners interested in social relationships, the question remains as to how large social networks typically are, and how their size and composition change across adulthood. On the basis of predictions of socioemotional selectivity theory and social convoy theory, we conducted a meta-analysis on age-related social network changes and the effects of life events on social networks using 277 studies with 177,635 participants from adolescence to old age. Cross-sectional as well as longitudinal studies consistently showed that (a) the global social network increased up until young adulthood and then decreased steadily, (b) both the personal network and the friendship network decreased throughout adulthood, (c) the family network was stable in size from adolescence to old age, and (d) other networks with coworkers or neighbors were important only in specific age ranges. Studies focusing on life events that occur at specific ages, such as transition to parenthood, job entry, or widowhood, demonstrated network changes similar to such age-related network changes. Moderator analyses detected that the type of network assessment affected the reported size of global, personal, and family networks. Period effects on network sizes occurred for personal and friendship networks, which have decreased in size over the last 35 years. Together the findings are consistent with the view that a portion of normative, age-related social network changes are due to normative, age-related life events. We discuss how these patterns of normative social network development inform research in social, evolutionary, cultural, and personality psychology. PMID:22642230

Wrzus, Cornelia; Hnel, Martha; Wagner, Jenny; Neyer, Franz J

2013-01-01

165

[Psychoneuroimmunology of the life span: impact of childhood stress on immune dysregulation and inflammatory disease in later life].  

PubMed

Studies have shown clearly that childhood mistreatment, abuse and neglect are associated with severe inflammatory disease in adulthood (e.?g. cancer, heart disease, autoimmune disorder) and shortened life span. This review deals with the psychoneuroimmunological pathways of this connection. It shows that chronic stressors interfere very early in life with those protective mechanisms of the biological stress system that normally down-regulate potentially harmful inflammation. In the long term, serious inflammatory diseases, such as allergic asthma, can result. In this review, the pathogenetic connections between allergic asthma and early stress and stress system dysfunction are discussed. As our understanding of the dysfunctional psychophysiological mechanisms of inflammatory disease increases, psychodiagnostic and psychotherapeutic intervention in the treatment of physical disease will become more specific. PMID:24248864

Schubert, Christian

2014-05-01

166

The ProSeal has a shorter life-span than the Classic laryngeal mask airway.  

PubMed

We tested the hypothesis that the life-span of the ProSeal laryngeal mask airway (LMA) is shorter than the Classic LMA. We also compared residual cuff volumes and changes in elastance and permeability with use. Six new size 4 ProSeal LMAs and 6 new size 4 Classic LMAs were tested. Each LMA underwent a simulated clinical use cycle until it failed the pre-use check tests. The simulated clinical use cycle comprised: i) inflating the cuff to the maximum recommended volume for 1 h; ii) immersion in an enzymatic solution for 3 min; iii) washing the external and internal surfaces; iv) automatic washing for 14 min (< or =85 degrees C); v) drying for 30 min (< or =75 degrees C); and vi) autoclaving at 134 degrees C for 4 min at 206 kPa. Before the first cycle and every 10 subsequent cycles, the cuff was inflated with 40 mL air and the intracuff pressure was measured immediately and 3 h later. The initial intracuff pressure was taken to be an inverse measure of the elastance or resistance to deformation, and the intracuff pressure change were taken as a measure of the permeability. The residual cuff volume was determined for 10 Classic and 10 ProSeal size 4 LMAs using a gas dilution technique. The mean +/- sd (range) longevity for the ProSeal LMA and Classic LMA was 82 +/- 23 (45-109) uses and 133 +/- 35 (76-176) uses, respectively. The ProSeal LMA has a shorter life-span than the Classic LMA (P = 0.01). For the ProSeal LMA, there was no change in elastance or permeability with use. For the Classic LMA, there was a decrease in elastance (P < 0.0001) and an increase in permeability (P < 0.0001) with use. The residual cuff volume was higher for the ProSeal LMA (2.6 +/- 1.3 mL versus 1.5 +/- 0.9, P = 0.04). We conclude that the life-span of the ProSeal LMA is shorter than the Classic LMA, but both exceed the manufacturer's recommendations of 40 uses. We recommend that reusable LMA devices be discarded when they fail the pre-use check tests, rather than after a specific number of uses. PMID:15673899

Doneley, Sarah; Brimacombe, Joseph; Keller, Christian; von Goedecke, Achim

2005-02-01

167

Biological impact of auditory expertise across the life span: musicians as a model of auditory learning.  

PubMed

Experience-dependent characteristics of auditory function, especially with regard to speech-evoked auditory neurophysiology, have garnered increasing attention in recent years. This interest stems from both pragmatic and theoretical concerns as it bears implications for the prevention and remediation of language-based learning impairment in addition to providing insight into mechanisms engendering experience-dependent changes in human sensory function. Musicians provide an attractive model for studying the experience-dependency of auditory processing in humans due to their distinctive neural enhancements compared to nonmusicians. We have only recently begun to address whether these enhancements are observable early in life, during the initial years of music training when the auditory system is under rapid development, as well as later in life, after the onset of the aging process. Here we review neural enhancements in musically trained individuals across the life span in the context of cellular mechanisms that underlie learning, identified in animal models. Musicians' subcortical physiologic enhancements are interpreted according to a cognitive framework for auditory learning, providing a model in which to study mechanisms of experience-dependent changes in human auditory function. PMID:23988583

Strait, Dana L; Kraus, Nina

2014-02-01

168

Protection throughout the life span: the psychoneuroimmunologic impact of Indo-Tibetan meditative and yogic practices.  

PubMed

The Indo-Tibetan tradition claims that proficiency in the suggested longevity practices of meditation, diet, and physical exercise (yoga), will result in profound anti-aging, stress-mediating and health enhancing effects. Western biomedical research has begun to demonstrate that the psychobiological states induced and cultivated by cognitive behavioral practices which are emblematic of those contained within the Indo-Tibetan tradition (hypnosis, meditation, visualization, systematic relaxation), indeed do have a profound impact on the body's protective and regulatory systems. Although continued study is necessary, much of the early research illuminating the mechanisms responsible for the life-span extending and health-enhancing effects of these cognitive behavioral practices points to the importance of their anti-inflammatory, anti-stress, and antioxidant effects as well as their impact in enhancing the production of endogenous substances that possess general longevity-enhancing, regenerative properties. PMID:19735248

Olivo, Erin L

2009-08-01

169

Stressors and antistressors: how do they influence life span in HER-2/neu transgenic mice?  

PubMed

The purpose of this study is to investigate possible influences of different stressors (saline injections, light deprivation and constant light regimen) and geroprotectors (Epitalon and melatonin) on survivals of female HER-2/neu transgenic mice. We propose a semi-parametric model of heterogeneous mortality (frailty model) for the analysis of the experimental data. In this model, we assume that treatment influences parameters of both frailty distribution and baseline hazard. The unique design of the experiments makes it possible to compare the effects on survival produced by different treatments in terms of changes in population heterogeneity and underlying hazard. Parameters of the model help to describe the possible influences of various stressors, geroprotectors, and their dosage on the life span of laboratory animals. The proposed model helps to advance our understanding of the effects--such as debilitation, longevity hormesis and incomplete hormesis--which occur in the population as a result of different treatments. PMID:15501020

Semenchenko, Ganna V; Anisimov, Vladimir N; Yashin, Anatoli I

2004-10-01

170

Life spans of a Bellman-Harris branching process with immigration  

SciTech Connect

One considers two schemes of the Bellman-Harris process with immigration when a) the lifetime of the particles is an integral-valued random variable and the immigration is defined by a sequence of independent random variables; b) the distribution of the lifetime of the particles is nonlattice and the immigration is a process with continuous time. One investigates the properties of the life spans of such processes. The results obtained here are a generalization to the case of Bellman-Harris processes of the results of A.M. Zubkov, obtained for Markov branching processes. For the proof one makes use in an essential manner of the known inequalities of Goldstein, estimating the generating function of the Bellman-Harris process in terms of the generating functions of the imbedded Galton-Watson process.

Badalbaev, I.S.; Mashrabbaev, A.

1987-09-10

171

Expectations about Memory Change Across the Life Span Are Impacted By Aging Stereotypes  

PubMed Central

This study examined whether expectations about memory change with age vary for different personality types. Four adjectives from each of Hummerts age-stereotype trait sets were selected to create 11 adjective clusters varying in both valence (positive versus negative) and relevance to memory functioning. Three hundred and seventy three participants in three age groups rated the memory abilities of target adults, defined by the adjective clusters, across the adult life span. Consistent with past studies, participants believed in age-related memory decline. However, participants rated target adults with positive personality traits as having better memory ability and less age-related memory decline than target adults with negative personality traits. This effect was larger when the traits were relevant to memory than when they were not. Finally, older participants were more strongly influenced by both the valence and the relevance of the personality descriptions than younger participants. PMID:19290748

Lineweaver, Tara T.; Berger, Andrea K.; Hertzog, Christopher

2008-01-01

172

Immune defense and reproductive pace of life in Peromyscus mice.  

PubMed

Immune activity is variable within and among vertebrates despite the potentially large fitness costs of pathogens to their hosts. From the perspective of life history theory, immunological variability may be the consequence of counterbalancing investments in immune defense against other expensive physiological processes, namely, reproduction. In the present study, we tested the hypothesis that immune defense among captive-bred, disease-free Peromyscus mice would be influenced by their reproductive life history strategies. Specifically, we expected that small species that reproduce prolifically and mature rapidly (i.e., fast pace of life) would favor inexpensive, nonspecific immune defenses to promote reproductive proclivity. Alternatively, we expected that large species that mature slowly and invest modestly in reproduction over multiple events (i.e., slow pace of life) would favor developmentally expensive, specific immune defenses and avoid cheap, nonspecific ones because such defenses are predisposed to self-damage. We found that species exhibited either strong ability to kill (gram-negative) bacteria, a developmentally inexpensive defense, or strong ability to produce antibodies against a novel protein, a developmentally expensive defense, but not both. Cell-mediated inflammation also varied significantly among species, but in a unique fashion relative to bacteria killing or antibody production; wound healing was comparatively similar among species. These results indicate that Peromyscus species use immune strategies that are constrained to a dominant axis, but this axis is not determined solely by reproductive pace of life. Further comparisons, ideally with broader phylogenetic coverage, could identify what ecological and evolutionary forces produce the pattern we detected. Importantly, our study indicates that species may not be differentially immunocompetent; rather, they use unique defense strategies to prevent infection. PMID:18027755

Martin, Lynn B; Weil, Zachary M; Nelson, Randy J

2007-10-01

173

Virtual navigation strategies from childhood to senescence: evidence for changes across the life span  

PubMed Central

This study sought to investigate navigational strategies across the life span, by testing 8-years old children to 80-years old healthy older adults on the 4 on 8 virtual maze (4/8VM). The 4/8VM was previously developed to assess spontaneous navigational strategies, i.e., hippocampal-dependent spatial strategies (navigation by memorizing relationships between landmarks) versus caudate nucleus-dependent response strategies (memorizing a series of left and right turns from a given starting position). With the 4/8VM, we previously demonstrated greater fMRI activity and gray matter in the hippocampus of spatial learners relative to response learners. A sample of 599 healthy participants was tested in the current study. Results showed that 84.4% of children, 46.3% of young adults, and 39.3% of older adults spontaneously used spatial strategies (p < 0.0001). Our results suggest that while children predominantly use spatial strategies, the proportion of participants using spatial strategies decreases across the life span, in favor of response strategies. Factors promoting response strategies include repetition, reward and stress. Since response strategies can result from successful repetition of a behavioral pattern, we propose that the increase in response strategies is a biological adaptive mechanism that allows for the automatization of behavior such as walking in order to free up hippocampal-dependent resources. However, the down-side of this shift from spatial to response strategies occurs if people stop building novel relationships, which occurs with repetition and routine, and thereby stop stimulating their hippocampus. Reduced fMRI activity and gray matter in the hippocampus were shown to correlate with cognitive deficits in normal aging. Therefore, these results have important implications regarding factors involved in healthy and successful aging. PMID:23162463

Bohbot, Veronique D.; McKenzie, Sam; Konishi, Kyoko; Fouquet, Celine; Kurdi, Vanessa; Schachar, Russel; Boivin, Michel; Robaey, Philippe

2012-01-01

174

Leaf life span, dynamics and construction cost of species from Mediterranean old-fields differing in successional status  

Microsoft Academic Search

Summary Variations in leaf life span (LLS), construction cost (CC) and dynamics patterns (periods of leaf production, t p , and loss, t L , time lag separating the end of leaf pro- duction and the beginning of leaf loss, t) were investigated in species differing in suc- cessional status and life forms. We tested how those traits varied

Marie-Laure Navas; Beatrice Ducout; Catherine Roumet; Jean Richarte; Joel Garnier; Eric Garnier

2003-01-01

175

Expressions of ecological identity across the life span of eight environmental exemplars  

NASA Astrophysics Data System (ADS)

While there is a substantial body of literature looking at various aspects of ecological identity and factors that influence it, there has been less work done on how an individual's ecological identity changes with time. Much of that work is limited to short segments of the life span (e.g. the impact of wilderness experiences). This dissertation attempts to address this perceived gap by investigating how the ecological identity of eight environmental exemplars changed during the course of his or her life. What has emerged from this qualitative grounded theory investigation of the lives and works of Charles Darwin, John Muir, Aldo Leopold, Marjory Stoneman Douglas, Hazel Wolf, Rachel Carson, James Lovelock and E.O. Wilson are five sequential expressions of ecological identity. These 'stages' serve as a framework to explain ecological identity as a developmental process, both fluid and continuous, rather than at) end product. The development of an ecological identity is traced, through the development of five cognitive foundations and their alignment with five emotional foundations that reflect a progression from a sensory interaction and a kinship bond with nature into a deep understanding of the interconnectedness of all aspects of the planet. The findings reveal the evolution of an ecological identity and suggest the importance of looking beyond content knowledge in the nurturing of ecological attitudes, values, and lifestyles.

Seydel, Jennifer

176

Aging Theories for Establishing Safe Life Spans of Airborne Critical Structural Components  

NASA Technical Reports Server (NTRS)

New aging theories have been developed to establish the safe life span of airborne critical structural components such as B-52B aircraft pylon hooks for carrying air-launch drop-test vehicles. The new aging theories use the equivalent-constant-amplitude loading spectrum to represent the actual random loading spectrum with the same damaging effect. The crack growth due to random loading cycling of the first flight is calculated using the half-cycle theory, and then extrapolated to all the crack growths of the subsequent flights. The predictions of the new aging theories (finite difference aging theory and closed-form aging theory) are compared with the classical flight-test life theory and the previously developed Ko first- and Ko second-order aging theories. The new aging theories predict the number of safe flights as considerably lower than that predicted by the classical aging theory, and slightly lower than those predicted by the Ko first- and Ko second-order aging theories due to the inclusion of all the higher order terms.

Ko, William L.

2003-01-01

177

A structural-developmental psychodynamic approach to psychopathology: two polarities of experience across the life span.  

PubMed

Consistent with principles of developmental psychopathology, this paper presents a broad psychodynamic structural developmental perspective that establishes conceptual continuities between processes of normal personality development, personality organization, concepts of psychopathology, and processes of therapeutic change. The major assumption of this approach is that personality development proceeds in a dialectic synergistic interaction between the development of capacities for interpersonal relatedness and the development of self-definition or identity. Extensive research demonstrates that these two dimensions define two broad types of personality organization, each with a particular experiential mode; preferred forms of cognition, defense, and adaptation; unique qualities of interpersonal relatedness and specific types of object and self-representation. Severe disruptions of this normal dialectic developmental process result in various forms of psychopathology organized in two basic configurations in which there is distorted defensive preoccupation, at different developmental levels, with one of these polarities (relatedness or self-definition) at the expense of the development of the other dimension. This paper reviews empirical findings supporting this approach to normal and disrupted personality development throughout the life cycle and considers its relationship to the internalizing-externalizing distinction in childhood and adolescence, attachment theory, and research on the interaction between biological and psychosocial factors in development across the life span. Finally, we discuss the implications of this approach for intervention and prevention. PMID:19583884

Blatt, Sidney J; Luyten, Patrick

2009-01-01

178

Biological Approaches to Mechanistically Understand the Healthy Life Span Extension Achieved by Calorie Restriction and Modulation of Hormones  

PubMed Central

Calorie restriction and reduced somatotropic (growth hormone and insulin-like growth factor-1) signaling have a widespread though not universal ability to extend life. These interventions are considered central tools to understanding the downstream events that lead to the increase in healthy life span. As these approaches have been validated, the animals phenotyped, and the mechanisms proposed, many challenges have emerged. In this article, we give several examples and propose several considerations, opportunities, and approaches that may identify major mechanisms through which these interventions exert their effects, and which may lead to drug therapy to increase health span. PMID:19228789

Bartke, Andrzej

2009-01-01

179

Dietary Intake of Curcuma longa and Emblica officinalis Increases Life Span in Drosophila melanogaster  

PubMed Central

Intake of food and nutrition plays a major role in affecting aging process and longevity. However, the precise mechanisms underlying the ageing process are still unclear. To this respect, diet has been considered to be a determinant of ageing process. In order to better illustrate this, we used Drosophila melanogaster as a model and fed them orally with different concentrations of two commonly used Indian medicinal plant products, Curcuma longa (rhizome) and Emblica officinalis (fruit). The results revealed significant increase in life span of Drosophila flies on exposure to both the plant products, more efficiently by C. Longa than by E. officinalis. In order to understand whether the increase in lifespan was due to high-antioxidant properties of these medicinal plants, we performed enzymatic assays to assess the SOD and catalase activities in case of both treated and control Drosophila flies. Interestingly, the results support the free radical theory of aging as both these plant derivatives show high reactive oxygen species (ROS) scavenging activities. PMID:24967413

Rawal, Shilpa; Singh, Pavneet; Gupta, Ayush; Mohanty, Sujata

2014-01-01

180

Atrx deficiency induces telomere dysfunction, endocrine defects, and reduced life span  

PubMed Central

Human ATRX mutations are associated with cognitive deficits, developmental abnormalities, and cancer. We show that the Atrx-null embryonic mouse brain accumulates replicative damage at telomeres and pericentromeric heterochromatin, which is exacerbated by loss of p53 and linked to ATM activation. ATRX-deficient neuroprogenitors exhibited higher incidence of telomere fusions and increased sensitivity to replication stressinducing drugs. Treatment of Atrx-null neuroprogenitors with the G-quadruplex (G4) ligand telomestatin increased DNA damage, indicating that ATRX likely aids in the replication of telomeric G4-DNA structures. Unexpectedly, mutant mice displayed reduced growth, shortened life span, lordokyphosis, cataracts, heart enlargement, and hypoglycemia, as well as reduction of mineral bone density, trabecular bone content, and subcutaneous fat. We show that a subset of these defects can be attributed to loss of ATRX in the embryonic anterior pituitary that resulted in low circulating levels of thyroxine and IGF-1. Our findings suggest that loss of ATRX increases DNA damage locally in the forebrain and anterior pituitary and causes tissue attrition and other systemic defects similar to those seen in aging. PMID:23563309

Watson, L. Ashley; Solomon, Lauren A.; Li, Jennifer Ruizhe; Jiang, Yan; Edwards, Matthew; Shin-ya, Kazuo; Beier, Frank; Berube, Nathalie G.

2013-01-01

181

?-N-methylamino-L-alanine induces neurological deficits and shortened life span in Drosophila.  

PubMed

The neurotoxic non-protein amino acid, ?-N-methylamino-L-alanine (BMAA), was first associated with the high incidence of Amyotrophic Lateral Sclerosis/Parkinsonism Dementia Complex (ALS/PDC) in Guam. Recently, BMAA has been implicated as a fierce environmental factor that contributes to the etiology of Alzheimer's and Parkinson's diseases, in addition to ALS. However, the toxicity of BMAA in vivo has not been clearly demonstrated. Here we report our investigation of the neurotoxicity of BMAA in Drosophila. We found that dietary intake of BMAA reduced life span, locomotor functions, and learning and memory abilities in flies. The severity of the alterations in phenotype is correlated with the concentration of BMAA detected in flies. Interestingly, developmental exposure to BMAA had limited impact on survival rate, but reduced fertility in females, and caused delayed neurological impairment in aged adults. Our studies indicate that BMAA exposure causes chronic neurotoxicity, and that Drosophila serves as a useful model in dissecting the pathogenesis of ALS/PDC. PMID:22069570

Zhou, Xianchong; Escala, Wilfredo; Papapetropoulos, Spyridon; Zhai, R Grace

2010-11-01

182

Telomerase alone extends the replicative life span of human skeletal muscle cells without compromising genomic stability.  

PubMed

Continuous cycles of muscle fiber necrosis and regeneration are characteristic of the muscular dystrophies, and in some cases this leads to premature replicative senescence of myoblasts in vitro. The molecular mechanism of senescence in human myoblasts is poorly understood but there is evidence to suggest that telomeric attrition may be one of the ways by which this is achieved. We report here, for the first time, the extension of normal human skeletal muscle cell replicative life span by the reconstitution of telomerase activity. The telomerase-expressing cells show no features of transformation in vitro and have stable genomes with diploid karyotypes, do not express exceptionally high levels of c-myc and have wild-type, unmethylated CDKN2A genes. In vivo, they regenerate to repair muscle injury in immunosuppressed RAG-1 mice. This work suggests that telomerase expression to repair short telomeres may aid the expansion of diploid human muscle cells and consequently attempts at gene therapy for muscle diseases. PMID:14577927

Wootton, Martha; Steeghs, Karen; Watt, Diana; Munro, June; Gordon, Katrina; Ireland, Hazel; Morrison, Vivienne; Behan, Wilhelmina; Parkinson, E Kenneth

2003-10-10

183

?-N-Methylamino-L-alanine Induces Neurological Deficits and Shortened Life Span in Drosophila  

PubMed Central

The neurotoxic non-protein amino acid, ?-N-methylamino-L-alanine (BMAA), was first associated with the high incidence of Amyotrophic Lateral Sclerosis/Parkinsonism Dementia Complex (ALS/PDC) in Guam. Recently, BMAA has been implicated as a fierce environmental factor that contributes to the etiology of Alzheimers and Parkinsons diseases, in addition to ALS. However, the toxicity of BMAA in vivo has not been clearly demonstrated. Here we report our investigation of the neurotoxicity of BMAA in Drosophila. We found that dietary intake of BMAA reduced life span, locomotor functions, and learning and memory abilities in flies. The severity of the alterations in phenotype is correlated with the concentration of BMAA detected in flies. Interestingly, developmental exposure to BMAA had limited impact on survival rate, but reduced fertility in females, and caused delayed neurological impairment in aged adults. Our studies indicate that BMAA exposure causes chronic neurotoxicity, and that Drosophila serves as a useful model in dissecting the pathogenesis of ALS/PDC. PMID:22069570

Zhou, Xianchong; Escala, Wilfredo; Papapetropoulos, Spyridon; Zhai, R. Grace

2010-01-01

184

[Genetic passport--basic contribution to active longevity and maximal life-span duration].  

PubMed

The review was made on gene pass conception as individual DNA data bank reflecting unique genetic peculiarities of each human, its major potential contribution in achievements of active longevity and creation most favorable conditions for maximal duration of individual life-span. Participation of major age-regulated genes such as biological clock genes and the weak chain genes in aging processes of humans is briefly outlined. The significance of genetic testing of allelic polymorphisms and marker-genes implicated in common multifactorial disorders is stressed. The problems evoked by genetic results interpretation are mentioned. Special attention is paid to Genome Wide Association Studies (GWAS) technology implemented for analysis of genetic profiles and candidate genes associated with common diseases. Scientific problems and social interests in creation of individually oriented DNA-data banks (Gene Passes) amenable for the pregnant women, children, sportsmen, etc. are discussed. The relationship of Gene Pass idea to the current international genetic program "Personificated Genome" is highlighted. Feasible perspectives for genetic testing and basic contribution of Gene Pass into gerontology practical medical service are reviewed. PMID:19827679

Baranov, V S; Baranova, E V

2009-01-01

185

A fasting-responsive signaling pathway that extends life span in C. elegans.  

PubMed

Intermittent fasting is one of the most effective dietary restriction regimens that extend life span in C. elegans and mammals. Fasting-stimulus responses are key to the longevity response; however, the mechanisms that sense and transduce the fasting stimulus remain largely unknown. Through a comprehensive transcriptome analysis in C. elegans, we find that along with the FOXO transcription factor DAF-16, AP-1 (JUN-1/FOS-1) plays a central role in fasting-induced transcriptional changes. KGB-1, one of the C. elegans JNKs, acts as an activator of AP-1 and is activated in response to fasting. KGB-1 and AP-1 are involved in intermittent fasting-induced longevity. Fasting-induced upregulation of the components of the SCF E3 ubiquitin ligase complex via AP-1 and DAF-16 enhances protein ubiquitination and reduces protein carbonylation. Our results thus identify a fasting-responsive KGB-1/AP-1 signaling pathway, which, together with DAF-16, causes transcriptional changes that mediate longevity, partly through regulating proteostasis. PMID:23352664

Uno, Masaharu; Honjoh, Sakiko; Matsuda, Mitsuhiro; Hoshikawa, Haruka; Kishimoto, Saya; Yamamoto, Tomohito; Ebisuya, Miki; Yamamoto, Takuya; Matsumoto, Kunihiro; Nishida, Eisuke

2013-01-31

186

Improvement/Maintenance and Reorientation as Central Features of Coping with Major Life Change and Loss: Contributions of Three Life-Span Theories  

ERIC Educational Resources Information Center

This article focuses on the common and unique contributions of three major life-span theories in addressing improvement/maintenance and reorientation, which represent central processes of coping with major life change and loss. For this purpose, we review and compare the dual-process model of assimilative and accommodative coping, the model of

Boerner, Kathrin; Jopp, Daniela

2007-01-01

187

Life history costs and consequences of rapid reproductive maturation in female rhesus macaques  

Microsoft Academic Search

Life history theory suggests that reproduction at one point in time involves costs in terms of energy, reduced survival, or probability of reproduction at a future point in time. ln long-lived iteroparous organisms, initiating reproduction at a relatively young age may exact a cost in terms of reduced survivorship, but an early age of first reproduction could be beneficial if

Fred B. Bercovitch; John D. Berard

1993-01-01

188

Comparing plant life histories using elasticity analysis: the importance of life span and the number of life-cycle stages  

Microsoft Academic Search

Recent studies have used transition matrix elasticity analysis to investigate the relative role of survival (L), growth (G) and fecundity (F) in determining the estimated rate of population increase for perennial plants. The relative importance of these three variables has then been used as a framework for comparing patterns of plant life history in a triangular parameter space. Here we

N. J. Enright; M. Franco; J. Silvertown

1995-01-01

189

Telling and Retelling Ones Self-Narrative: A Contextual Approach to Life-Span Development  

Microsoft Academic Search

In the context of a contextual or narrative metamodel of life-span development, a method of self-investigation is described. The method enables a person to tell his or her life story to a psychologist in a way that results in an overview of valuations, including moral valuations, referring to the persons past, present, and future. This process reveals the affective and

Hubert J. M. Hermans

1992-01-01

190

HIV1 dynamics in vivo: Virion clearance rate, infected cell life-span, and viral generation time  

Microsoft Academic Search

A new mathematical model was used to analyze a detailed set of human immunodeficiency virus-type 1 (HIV-1) viral load data collected from five infected individuals after the administration of a potent inhibitor of HIV-1 protease. Productively infected cells were estimated to have, on average, a life-span of 2.2 days (half-life t = 1.6 days), and plasma virions were estimated to

A. S. Perelson; A. U. Neumann; M. Markowitz; D. D. Ho; J. M. Leonard

1996-01-01

191

Living the Dream? A Qualitative Retrospective Study Exploring the Role of Adolescent Aspirations across the Life Span  

ERIC Educational Resources Information Center

There is a lack of longitudinal research linking adolescent career aspirations to adult outcomes other than career and income attainment. Drawing on Nurmi's (2004) and Salmela-Aro, Aunola, and Nurmi's (2007) life-span model of motivation and using quantitative survey data at ages 16, 23, 33, 42, and 50 years, combined with retrospective interview

Ashby, Julie S.; Schoon, Ingrid

2012-01-01

192

Modeling Life-Span Growth Curves of Cognition Using Longitudinal Data with Multiple Samples and Changing Scales of Measurement  

ERIC Educational Resources Information Center

The authors use multiple-sample longitudinal data from different test batteries to examine propositions about changes in constructs over the life span. The data come from 3 classic studies on intellectual abilities in which, in combination, 441 persons were repeatedly measured as many as 16 times over 70 years. They measured cognitive constructs

McArdle, John J.; Grimm, Kevin J.; Hamagami, Fumiaki; Bowles, Ryan P.; Meredith, William

2009-01-01

193

The living, the dead, and the expected dead: variation in life span yields little bias of proportional abundances in bivalve  

E-print Network

The living, the dead, and the expected dead: variation in life span yields little bias sets on the living and dead abundances of marine bivalves in local habitats is combined with a global assemblages relative to their standing abundance in the living community, but the magnitude of the distortion

Boyce, C. Kevin

194

Oxidative stress tolerance, adenylate cyclase, and autophagy are key players in the chronological life span of Saccharomyces cerevisiae during winemaking.  

PubMed

Most grape juice fermentation takes place when yeast cells are in a nondividing state called the stationary phase. Under such circumstances, we aimed to identify the genetic determinants controlling longevity, known as the chronological life span. We identified commercial strains with both short (EC1118) and long (CSM) life spans in laboratory growth medium and compared them under diverse conditions. Strain CSM shows better tolerance to stresses, including oxidative stress, in the stationary phase. This is reflected during winemaking, when this strain has an increased maximum life span. Compared to EC1118, CSM overexpresses a mitochondrial rhodanese gene-like gene, RDL2, whose deletion leads to increased reactive oxygen species production at the end of fermentation and a correlative loss of viability at this point. EC1118 shows faster growth and higher expression of glycolytic genes, and this is related to greater PKA activity due to the upregulation of the adenylate cyclase gene. This phenotype has been linked to the presence of a ? element in its promoter, whose removal increases the life span. Finally, EC1118 exhibits a higher level of protein degradation by autophagy, which might help achieve fast growth at the expense of cellular structures and may be relevant for long-term survival under winemaking conditions. PMID:22327582

Orozco, Helena; Matallana, Emilia; Aranda, Agustn

2012-04-01

195

Oxidative Stress Tolerance, Adenylate Cyclase, and Autophagy Are Key Players in the Chronological Life Span of Saccharomyces cerevisiae during Winemaking  

PubMed Central

Most grape juice fermentation takes place when yeast cells are in a nondividing state called the stationary phase. Under such circumstances, we aimed to identify the genetic determinants controlling longevity, known as the chronological life span. We identified commercial strains with both short (EC1118) and long (CSM) life spans in laboratory growth medium and compared them under diverse conditions. Strain CSM shows better tolerance to stresses, including oxidative stress, in the stationary phase. This is reflected during winemaking, when this strain has an increased maximum life span. Compared to EC1118, CSM overexpresses a mitochondrial rhodanese gene-like gene, RDL2, whose deletion leads to increased reactive oxygen species production at the end of fermentation and a correlative loss of viability at this point. EC1118 shows faster growth and higher expression of glycolytic genes, and this is related to greater PKA activity due to the upregulation of the adenylate cyclase gene. This phenotype has been linked to the presence of a ? element in its promoter, whose removal increases the life span. Finally, EC1118 exhibits a higher level of protein degradation by autophagy, which might help achieve fast growth at the expense of cellular structures and may be relevant for long-term survival under winemaking conditions. PMID:22327582

Orozco, Helena; Matallana, Emilia

2012-01-01

196

Due to hardware limitations dur-ing the first 20-year-span of life of the  

E-print Network

NEXRAD Now Due to hardware limitations dur- ing the first 20-year-span of life of the WSR-88D- ticular periodic update cycle that did not change, regardless of current meteorological conditions the Storm Page 11 ROC Stars Page 12 PRF Modification Now Available for SZ-2 VCPs Table 1: Best case AVSET

197

Although the maximum human life span of 122 years is well established, the genetic and biochemical changes  

E-print Network

and biochemical changes that influence the ability to reach old age in good physical and mental health been shown to be activated by caloric restriction or oxidative stress, resulting in increased life span-of-function approaches have provided clear evidence that FoxO is important in the Hydra stem cell system [8

198

Royal Jelly prolongs the life span of C3H/HeJ mice: correlation with reduced DNA damage.  

PubMed

In this study, we investigate the effect of dietary Royal Jelly (RJ) on tissue DNA oxidative damage and on the life span of C3H/HeJ mice. In C3H/HeJ mice that were fed a dietary supplement of RJ for 16 weeks, the levels of 8-hydroxy-2-deoxyguanosine (8-OHdG), a marker of oxidative stress, were significantly reduced in kidney DNA and serum. Secondly, we determined the effect of dietary RJ on the life span in C3H/HeJ mice. The 50% mice survivals of intermediate- (about 6 mg/kg weight) and high-dose groups (about 60 mg/kg weight) were reached at significantly longer times than that of the control group according to the generalized Wilcoxon test (p<0.05). The average survival times were 88 weeks for the control group vs. 79 weeks for the low-dose group (about 0.6 mg/kg weight), 112 weeks for the intermediate-dose group and 110 weeks for the high-dose group, respectively, showing that RJ extended the average survival time by about 25% compared to the control group. However, RJ did not extend the total life span. These results indicated that dietary RJ increased the average life span of C3H/HeJ mice, possibly through the mechanism of reduced oxidative damage. PMID:12954483

Inoue, Shin-ichiro; Koya-Miyata, Satomi; Ushio, Shimpei; Iwaki, Kanso; Ikeda, Masao; Kurimoto, Masashi

2003-09-01

199

Metabolism, Body Size and Life Span: A Case Study in Evolutionarily Divergent Populations of the Garter Snake (Thamnophis elegans)  

E-print Network

on an apparent negative relationship between mass-specific metabolic rate and lifespan in endotherms lineages of endotherms--birds and mammals, but there is still much to be discovered of the causative links endothermic species, that relate life span to physiology have long been a fruitful research area

Bronikowski, Anne

200

The Structure of Working Memory Abilities Across the Adult Life Span  

Microsoft Academic Search

The present study addresses three questions regarding age differences in working memory: (1) whether performance on complex span tasks decreases as a function of age at a faster rate than performance on simple span tasks; (2) whether spatial working memory decreases at a faster rate than verbal working memory; and (3) whether the structure of working memory abilities is different

Sandra Hale; Nathan S. Rose; Joel Myerson; Michael J. Strube; Mitchell Sommers; Nancy Tye-Murray; Brent Spehar

2011-01-01

201

Cinnamomum cassia Bark in Two Herbal Formulas Increases Life Span in Caenorhabditis elegans via Insulin Signaling and Stress Response Pathways  

PubMed Central

Background Proving the efficacy and corresponding mode of action of herbal supplements is a difficult challenge for evidence-based herbal therapy. A major hurdle is the complexity of herbal preparations, many of which combine multiple herbs, particularly when the combination is assumed to be vitally important to the effectiveness of the herbal therapy. This issue may be addressed through the use of contemporary methodology and validated animal models. Methods and Principal Findings In this study, two commonly used traditional herbal formulas, Shi Quan Da Bu Tang (SQDB) and Huo Luo Xiao Ling Dan (HLXL) were evaluated using a survival assay and oxidative stress biomarkers in a well-established C. elegans model of aging. HLXL is an eleven herb formula modified from a top-selling traditional herbal formula for the treatment of arthritic joint pain. SQDB consists of ten herbs often used for fatigue and energy, particularly in the aged. We demonstrate here that SQDB significantly extend life span in a C. elegans model of aging. Among all individual herbs tested, two herbs Cinnamomum cassia bark (Chinese pharmaceutical name: Cinnamomi Cortex, CIN) and Panax ginseng root (Chinese pharmaceutical name: Ginseng Radix, GS) significantly extended life span in C. elegans. CIN in both SQDB and HLXL formula extended life span via modulation of multiple longevity assurance genes, including genes involved in insulin signaling and stress response pathways. All the life-span-extending herbs (SQDB, CIN and GS) also attenuated levels of H2O2 and enhanced small heat shock protein expression. Furthermore, the life span-extending herbs significantly delayed human amyloid beta (A?)-induced toxicity in transgenic C. elegans expressing human A?. Conclusion/Significance These results validate an invertebrate model for rapid, systematic evaluation of commonly used Chinese herbal formulations and may provide insight for designing future evidence-based herbal therapy(s). PMID:20179756

Yu, Young-Beob; Dosanjh, Laura; Lao, Lixing; Tan, Ming; Shim, Bum Sang; Luo, Yuan

2010-01-01

202

Families Enriched for Exceptional Longevity also have Increased Health-Span: Findings from the Long Life Family Study  

PubMed Central

Hypothesizing that members of families enriched for longevity delay morbidity compared to population controls and approximate the health-span of centenarians, we compared the health-spans of older generation subjects of the Long Life Family Study (LLFS) to controls without family history of longevity and to centenarians of the New England Centenarian Study (NECS) using Bayesian parametric survival analysis. We estimated hazard ratios, the ages at which specific percentiles of subjects had onsets of diseases, and the gain of years of disease-free survival in the different cohorts compared to referent controls. Compared to controls, LLFS subjects had lower hazards for cancer, cardiovascular disease, severe dementia, diabetes, hypertension, osteoporosis, and stroke. The age at which 20% of the LLFS siblings and probands had one or more age-related diseases was approximately 10?years later than NECS controls. While female NECS controls generally delayed the onset of age-related diseases compared with males controls, these gender differences became much less in the older generation of the LLFS and disappeared amongst the centenarians of the NECS. The analyses demonstrate extended health-span in the older subjects of the LLFS and suggest that this aging cohort provides an important resource to discover genetic and environmental factors that promote prolonged health-span in addition to longer life-span. PMID:24350207

Sebastiani, Paola; Sun, Fangui X.; Andersen, Stacy L.; Lee, Joseph H.; Wojczynski, Mary K.; Sanders, Jason L.; Yashin, Anatoli; Newman, Anne B.; Perls, Thomas T.

2013-01-01

203

Families Enriched for Exceptional Longevity also have Increased Health-Span: Findings from the Long Life Family Study.  

PubMed

Hypothesizing that members of families enriched for longevity delay morbidity compared to population controls and approximate the health-span of centenarians, we compared the health-spans of older generation subjects of the Long Life Family Study (LLFS) to controls without family history of longevity and to centenarians of the New England Centenarian Study (NECS) using Bayesian parametric survival analysis. We estimated hazard ratios, the ages at which specific percentiles of subjects had onsets of diseases, and the gain of years of disease-free survival in the different cohorts compared to referent controls. Compared to controls, LLFS subjects had lower hazards for cancer, cardiovascular disease, severe dementia, diabetes, hypertension, osteoporosis, and stroke. The age at which 20% of the LLFS siblings and probands had one or more age-related diseases was approximately 10?years later than NECS controls. While female NECS controls generally delayed the onset of age-related diseases compared with males controls, these gender differences became much less in the older generation of the LLFS and disappeared amongst the centenarians of the NECS. The analyses demonstrate extended health-span in the older subjects of the LLFS and suggest that this aging cohort provides an important resource to discover genetic and environmental factors that promote prolonged health-span in addition to longer life-span. PMID:24350207

Sebastiani, Paola; Sun, Fangui X; Andersen, Stacy L; Lee, Joseph H; Wojczynski, Mary K; Sanders, Jason L; Yashin, Anatoli; Newman, Anne B; Perls, Thomas T

2013-01-01

204

TGF- Sma\\/Mab Signaling Mutations Uncouple Reproductive Aging from Somatic Aging  

Microsoft Academic Search

Female reproductive cessation is one of the earliest age-related declines humans experience, occurring in mid-adulthood. Similarly, Caenorhabditis elegans' reproductive span is short relative to its total life span, with reproduction ceasing about a third into its 15-20 day adulthood. All of the known mutations and treatments that extend C. elegans' reproductive period also regulate longevity, suggesting that reproductive span is

Shijing Luo; Wendy M. Shaw; Jasmine Ashraf; Coleen T. Murphy

2009-01-01

205

Life-span changes to adults' language: Effects of memory and genre  

E-print Network

; and a written statement recounting the most significant event in their lives. In addition, the WAIS vocabulary and digit-span tests were administered to the adults. Age-related changes in the length, clause structure, and fluency of the adults' oral.... Correlations be tween the length, clause, and fluency measures from the language samples and the education, health, and WAIS vocabulary and digit-span tests revealed that better-educated adults scored higher on the WAIS vocabulary test, produced longer...

Kemper, Susan; Kynette, Donna; Rash, Shannon; O'Brien, Kevin

1989-01-01

206

Association between life span extension by caloric restriction and thiol redox state in two different strains of mice  

PubMed Central

The hypothesis that the life-extending effect of caloric restriction (CR) is associated with an attenuation of the age-related pro-oxidant shift in the thiol redox state was tested employing a novel experimental design. Amounts of GSH, GSSG and protein mixed disulfides (Pr-SSG) in the skeletal muscle and liver were compared between two strains of mice, which have similar life spans when fed ad libitum (AL), however, under the standard CR regimen, life span of only one strain, C57BL/6, is extended, whereas it remains unaffected in the other strain, DBA/2. Mice were fed AL or 40% less food starting at 4 months and compared at 6 and 24 months of age. The amounts of GSSG and Pr-SSG increased and the GSH:GSSG ratios decreased with age in both strains of AL-fed mice. CR prevented these age-related changes in the C57BL/6, whose life span is extended by CR, but not in the DBA/2 mice, in which it remains unaffected. CR enhanced the activity of glutamate cysteine ligase in the C57BL/6, but not in the DBA/2 mice. Results suggest that longevity extension by CR may be associated with the attenuation of age-related pro-oxidizing shifts in the thiol redox state. PMID:21530646

Rebrin, Igor; Forster, Michael J.; Sohal, Rajindar S.

2011-01-01

207

Personal Theories about the Life-Span Development of Ones Self in Autobiographical Self-Presentations of Adults  

Microsoft Academic Search

Comprehensive autobiographies of middle-aged and older individuals are probed for self-presentations of both the authors subjective sense of continuity and change of self and their views about the course of development of the self. Compared with nomothetic data on these two major components of personal theories about the life-span development of self, the autobiographical data provide an especially rich source

Amos Handel

1987-01-01

208

Dietary Restriction in Mice Beginning at 1 Year of Age: Effect on Life-Span and Spontaneous Cancer Incidence  

Microsoft Academic Search

Lifelong dietary restriction beginning at 3 to 6 weeks of age in rodents is known to decelerate the rate of aging, increase mean and maximum life-spans, and inhibit the occurrence of many spontaneous cancers. Little is known about the effects of dietary restriction started in middle age. In the experiments now reported the food intake of 12- to 13-month-old mice

Richard Weindruch; Roy L. Walford

1982-01-01

209

Royal Jelly prolongs the life span of C3H\\/HeJ mice: correlation with reduced DNA damage  

Microsoft Academic Search

In this study, we investigate the effect of dietary Royal Jelly (RJ) on tissue DNA oxidative damage and on the life span of C3H\\/HeJ mice. In C3H\\/HeJ mice that were fed a dietary supplement of RJ for 16 weeks, the levels of 8-hydroxy-2-deoxyguanosine (8-OHdG), a marker of oxidative stress, were significantly reduced in kidney DNA and serum. Secondly, we determined

Shin-ichiro Inoue; Satomi Koya-Miyata; Shimpei Ushio; Kanso Iwaki; Masao Ikeda; Masashi Kurimoto

2003-01-01

210

Effects of shortened host life span on the evolution of parasite life history and virulence in a microbial host-parasite system  

Microsoft Academic Search

BACKGROUND: Ecological factors play an important role in the evolution of parasite exploitation strategies. A common prediction is that, as shorter host life span reduces future opportunities of transmission, parasites compensate with an evolutionary shift towards earlier transmission. They may grow more rapidly within the host, have a shorter latency time and, consequently, be more virulent. Thus, increased extrinsic (i.e.,

Thibault Nidelet; Jacob C Koella; Oliver Kaltz

2009-01-01

211

Effect of Epitalon on biomarkers of aging, life span and spontaneous tumor incidence in female Swiss-derived SHR mice.  

PubMed

From the age of 3 months until their natural deaths, female outbred Swiss-derived SHR mice were subcutaneously injected on 5 consecutive days every month with 0.1 ml of normal saline (control) or with 1.0 microg/mouse (approximately 30-40 microg/kg) of tetrapeptide Epitalon (Ala-Glu-Asp-Gly) dissolved in 0.1 ml saline. There were 54 mice in each group. The results of this study show that treatment with Epitalon did not influence food consumption, body weight or mean life span of mice. However, it slowed down the age-related switching-off of estrous function and decreased the frequency of chromosome aberrations in bone marrow cells (by 17.1%, P<0.05). It also increased by 13.3% the life span of the last 10% of the survivors (P<0.01) and by 12.3% the maximum life span in comparison with the control group. We also found that treatment with Epitalon did not influence total spontaneous tumor incidence, but inhibited the development of leukemia (6.0-fold), as compared with the control group. The data obtained suggest a geroprotector activity of Epitalon and the safety of its long-term administration in mice. PMID:14501183

Anisimov, Vladimir N; Khavinson, Vladimir Kh; Popovich, Irina G; Zabezhinski, Mark A; Alimova, Irina N; Rosenfeld, Svetlana V; Zavarzina, Natalia Yu; Semenchenko, Anna V; Yashin, Anatoli I

2003-01-01

212

elf-reproduction is central to biological life for long-term sustainability and  

E-print Network

S elf-reproduction is central to biological life for long-term sustainability and evolutionary- reproduction have not been exploited in machine design1 . Here we create simple machines that act as autonomous modular robots and are capable of physical self- reproduction using a set of cubes. A physical system

Napp, Nils

213

Delayed accumulation of intestinal coliform bacteria enhances life span and stress resistance in Caenorhabditis elegans fed respiratory deficient E. coli  

PubMed Central

Background Studies with the nematode model Caenorhabditis elegans have identified conserved biochemical pathways that act to modulate life span. Life span can also be influenced by the composition of the intestinal microbiome, and C. elegans life span can be dramatically influenced by its diet of Escherichia coli. Although C. elegans is typically fed the standard OP50 strain of E. coli, nematodes fed E. coli strains rendered respiratory deficient, either due to a lack coenzyme Q or the absence of ATP synthase, show significant life span extension. Here we explore the mechanisms accounting for the enhanced nematode life span in response to these diets. Results The intestinal load of E. coli was monitored by determination of worm-associated colony forming units (cfu/worm or coliform counts) as a function of age. The presence of GFP-expressing E. coli in the worm intestine was also monitored by fluorescence microscopy. Worms fed the standard OP50 E. coli strain have high cfu and GFP-labeled bacteria in their guts at the L4 larval stage, and show saturated coliform counts by day five of adulthood. In contrast, nematodes fed diets of respiratory deficient E. coli lacking coenzyme Q lived significantly longer and failed to accumulate bacteria within the lumen at early ages. Animals fed bacteria deficient in complex V showed intermediate coliform numbers and were not quite as long-lived. The results indicate that respiratory deficient Q-less E. coli are effectively degraded in the early adult worm, either at the pharynx or within the intestine, and do not accumulate in the intestinal tract until day ten of adulthood. Conclusions The findings of this study suggest that the nematodes fed the respiratory deficient E. coli diet live longer because the delay in bacterial colonization of the gut subjects the worms to less stress compared to worms fed the OP50 E. coli diet. This work suggests that bacterial respiration can act as a virulence factor, influencing the ability of bacteria to colonize and subsequently harm the animal host. Respiratory deficient bacteria may pose a useful model for probing probiotic relationships within the gut microbiome in higher organisms. PMID:23256533

2012-01-01

214

The relationship between P3 and neuropsychological function in an adult life span sample  

Microsoft Academic Search

The relationship of P3 to age and neuropsychological performance was investigated in a sample of 71 well-functioning adults ranging in age from 21.8 to 94.7 years. ERPs were recorded while the participants performed an auditory two-stimuli oddball task in which the rare tones were to be counted. The Wechsler Abbreviated Scale of Intelligence (WASI) and the digit span subtest from

Kristine B Walhovd; Anders M Fjell

2003-01-01

215

Language Decline Across the Life Span: Findings From the Nun Study  

Microsoft Academic Search

The present study examines language samples from the Nun Study. Measures of grammatical complexity and idea density were obtained from autobiographies written over a 60-year span. Participants who had met criteria for dementia were contrasted with those who did not. Grammatical complexity initially averaged 4.78 ( on a 0-to-7-point scale) for participants who did not meet criteria for dementia and

Susan Kemper; Lydia H. Greiner; Janet G. Marquis; Katherine Prenovost; Tracy L. Mitzner

2001-01-01

216

Qualitative Age Differences in Memory for Text: A Life-Span Developmental Perspective  

Microsoft Academic Search

Qualitative differences in memory for text among 4 age groups (mean ages = 14.14, 17.55, 48.35, and 67.12 years) were examined in this study. Participants produced written recall and summary responses after presentation of a story and an essay. The response protocols were scored for their reproductive, elaborative, and metaphoric content. Age-group differences were observed in the quality of the

Cynthia Adams

1991-01-01

217

Extension of Life Span by Impaired Glucose Metabolism in Caenorhabditis elegans Is Accompanied by Structural Rearrangements of the Transcriptomic Network  

PubMed Central

Glucose restriction mimicked by feeding the roundworm Caenorhabditis elegans with 2-deoxy-D-glucose (DOG) - a glucose molecule that lacks the ability to undergo glycolysis - has been found to increase the life span of the nematodes considerably. To facilitate understanding of the molecular mechanisms behind this life extension, we analyzed transcriptomes of DOG-treated and untreated roundworms obtained by RNA-seq at different ages. We found that, depending on age, DOG changes the magnitude of the expression values of about 2 to 24 percent of the genes significantly, although our results reveal that the gross changes introduced by DOG are small compared to the age-induced changes. We found that 27 genes are constantly either up- or down-regulated by DOG over the whole life span, among them several members of the cytochrome P450 family. The monotonic change with age of the temporal expression patterns of the genes was investigated, leading to the result that 21 genes reverse their monotonic behaviour under impaired glycolysis. Put simply, the DOG-treatment reduces the gross transcriptional activity but increases the interconnectedness of gene expression. However, a detailed analysis of network parameters discloses that the introduced changes differ remarkably between individual signalling pathways. We found a reorganization of the hubs of the mTOR pathway when standard diet is replaced by DOG feeding. By constructing correlation based difference networks, we identified those signalling pathways that are most vigorously changed by impaired glycolysis. Taken together, we have found a number of genes and pathways that are potentially involved in the DOG-driven extension of life span of C. elegans. Furthermore, our results demonstrate how the network structure of ageing-relevant signalling pathways is reorganised under impaired glycolysis. PMID:24204961

Priebe, Steffen; Menzel, Uwe; Zarse, Kim; Groth, Marco; Platzer, Matthias; Ristow, Michael; Guthke, Reinhard

2013-01-01

218

Female temperament, tumor development and life span: Relation to glucocorticoid and tumor necrosis factor ? levels in rats  

PubMed Central

Behavioral characteristics closely associated with specific physiological profiles present an important area of research in understanding health disparities. In particular, glucocorticoid overproduction may be an important factor moderating disease progression; natural variance in production of this steroid has been proposed as one mechanism underlying individual differences in health and disease. In the current paper, we examined immune parameters in female rats of two different behavioral types previously shown to have differential glucocorticoid production and life spans. We categorized young female rats according to their behavioral response to novelty (high- or low-locomotion), and compared their glucocorticoid production, adrenal size, thymus size, tumor necrosis factor-? (TNF-?) production, tumor development and life span. As expected, high-locomotion females produced more glucocorticoids and had larger adrenal glands during young adulthood than did low-locomotion females. High-locomotion females had significantly smaller thymuses and reduced TNF-? levels compared to low-locomotion, suggesting altered immune function in young adulthood. Finally, high-locomotion females had shorter life spans than did low-locomotion females, and this was particularly true in females that developed pituitary tumors, but not in those that developed mammary tumors. These results, along with other published findings, suggest that high-locomotion rodent females experience life-long elevations in glucocorticoid responses to novelty, and that these elevated levels may be comparable to chronic stress. This naturally-occurring endocrine profile may influence immune responses which in turn could affect disease susceptibility. Variance in immune function across personality types may be partially moderated by natural variance in glucocorticoid production. PMID:18155400

Cavigelli, Sonia A.; Bennett, Jeanette M.; Michael, Kerry C.; Klein, Laura Cousino

2008-01-01

219

Isoforms and half-life of FSH from sheep with different reproductive states  

Microsoft Academic Search

The glycoprotein hormone FSH comes in many different isoforms. In humans and rats the charges of the FSH isoforms vary with reproductive state and these affect the half-life of FSH in plasma. In this study we examined the charge heterogeneity of FSH in pituitary extracts from sheep with different reproductive states. Also the half-life of clearance of pituitary FSH from

L G Moore; W Ng Chie; N L Hudson; K P McNatty

2000-01-01

220

Marine collagen peptides prepared from chum salmon (Oncorhynchus keta) skin extend the life span and inhibit spontaneous tumor incidence in Sprague-Dawley Rats.  

PubMed

To observe the effects of marine collagen peptides (MCPs) prepared from chum salmon (Oncorhynchus keta) skin on life span and spontaneous tumor incidence, Sprague-Dawley rats were fed diets supplemented with MCP at concentrations of 0%, 2.25%, 4.5%, and 9% (wt/wt) from the age of 4 weeks until natural death. There were 40 rats in each group (male:female ratio = 1:1). The results showed that the MCP did not significantly influence body weight or food consumption of rats of either sex throughout the life span; it did dose-dependently inhibit the age-related decrease in the activities of antioxidant enzymes and the age-related increase in the levels of lipid peroxidation product in both sexes. MCP notably increased the mean life span, the life span of the last 30% of the survivors, and the maximal life span; it decreased overall spontaneous tumor incidence of both sexes with significance in the 4.5% and 9% MCP-treated male groups and 9% MCP-treated female group. Compared to the control group, the incidence of death from tumors was decreased in MCP groups in comparison with the control group of both sexes. Therefore, we concluded that MCPs dose-dependently increase life span and decrease spontaneous tumor incidence in Sprague-Dawley rats. Moreover, the antioxidative property of MCPs may be responsible for the increased life span and protection against tumor development. PMID:20553190

Liang, Jiang; Pei, Xin-Rong; Wang, Nan; Zhang, Zhao-Feng; Wang, Jun-Bo; Li, Yong

2010-08-01

221

The relationship between P3 and neuropsychological function in an adult life span sample.  

PubMed

The relationship of P3 to age and neuropsychological performance was investigated in a sample of 71 well-functioning adults ranging in age from 21.8 to 94.7 years. ERPs were recorded while the participants performed an auditory two-stimuli oddball task in which the rare tones were to be counted. The Wechsler Abbreviated Scale of Intelligence (WASI) and the digit span subtest from the Wechsler Adult Intelligence Scale-R (WAIS-R) were administered. Regression analyses showed significant, linear effects of age on P3 latency and amplitude. Significant relationships between P3 and neuropsychological measures were found, in that P3 latency correlated moderately in predictable ways with scores on matrices, block design, and digit span. Overall, these relationships are best characterized by a linear function, but a non-linear component is involved in the relationship between P3 latency and fluid tests. Finally, a linear relationship between ERP components and age was found, while a curvilinear relationship was found between age and block design and matrices, respectively. There appears to be either partially different functions or structures underlying performance on these tests, the P3 component and performance on neuropsychological tests, or one must assume some variant of a multiplicative, as opposed to an additive, model of cognition. PMID:12505768

Walhovd, Kristine B; Fjell, Anders M

2003-01-01

222

Genetic manipulation of longevity-related genes as a tool to regulate yeast life span and metabolite production during winemaking  

PubMed Central

Background Yeast viability and vitality are essential for different industrial processes where the yeast Saccharomyces cerevisiae is used as a biotechnological tool. Therefore, the decline of yeast biological functions during aging may compromise their successful biotechnological use. Life span is controlled by a variety of molecular mechanisms, many of which are connected to stress tolerance and genomic stability, although the metabolic status of a cell has proven a main factor affecting its longevity. Acetic acid and ethanol accumulation shorten chronological life span (CLS), while glycerol extends it. Results Different age-related gene classes have been modified by deletion or overexpression to test their role in longevity and metabolism. Overexpression of histone deacetylase SIR2 extends CLS and reduces acetate production, while overexpression of SIR2 homolog HST3 shortens CLS, increases the ethanol level, and reduces acetic acid production. HST3 overexpression also enhances ethanol tolerance. Increasing tolerance to oxidative stress by superoxide dismutase SOD2 overexpression has only a moderate positive effect on CLS. CLS during grape juice fermentation has also been studied for mutants on several mRNA binding proteins that are regulators of gene expression at the posttranscriptional level; we found that NGR1 and UTH4 deletions decrease CLS, while PUF3 and PUB1 deletions increase it. Besides, the pub1? mutation increases glycerol production and blocks stress granule formation during grape juice fermentation. Surprisingly, factors relating to apoptosis, such as caspase Yca1 or apoptosis-inducing factor Aif1, play a positive role in yeast longevity during winemaking as their deletions shorten CLS. Conclusions Manipulation of regulators of gene expression at both transcriptional (i.e., sirtuins) and posttranscriptional (i.e., mRNA binding protein Pub1) levels allows to modulate yeast life span during its biotechnological use. Due to links between aging and metabolism, it also influences the production profile of metabolites of industrial relevance. PMID:23282100

2013-01-01

223

Comparison of Building Energy Efficiency and Life Span for Different Envelopes  

E-print Network

Unsuitable building energy saving technology will result in plenty building trash and waste buildings. In China, the life of many buildings is less than 50 years because of improper building heat preservation envelopes. It is found that irrational...

Li, Z.; Li, D.; Li, L.; Zhang, G.; Liu, J.

2006-01-01

224

Influence of early-life nutrition on mortality and reproductive success during a subsequent famine  

E-print Network

-life conditions, no study on humans has demonstrated the predicted fitness benefit under low later-life nutrition of metabolic diseases. developmental plasticity | silver spoon | human life-history | DoHAD Nutrition duringInfluence of early-life nutrition on mortality and reproductive success during a subsequent famine

Lummaa, Virpi

225

DNA damage leads to progressive replicative decline but extends the life span of long-lived mutant animals  

PubMed Central

Human-nucleotide-excision repair (NER) deficiency leads to different developmental and segmental progeroid symptoms of which the pathogenesis is only partially understood. To understand the biological impact of accumulating spontaneous DNA damage, we studied the phenotypic consequences of DNA-repair deficiency in Caenorhabditis elegans. We find that DNA damage accumulation does not decrease the adult life span of post-mitotic tissue. Surprisingly, loss of functional ERCC-1/XPF even further extends the life span of long-lived daf-2 mutants, likely through an adaptive activation of stress signaling. Contrariwise, NER deficiency leads to a striking transgenerational decline in replicative capacity and viability of proliferating cells. DNA damage accumulation induces severe, stochastic impairment of development and growth, which is most pronounced in NER mutants that are also impaired in their response to ionizing radiation and inter-strand crosslinks. These results suggest that multiple DNA-repair pathways can protect against replicative decline and indicate that there might be a direct link between the severity of symptoms and the level of DNA-repair deficiency in patients. PMID:24013725

Lans, H; Lindvall, J M; Thijssen, K; Karambelas, A E; Cupac, D; Fensgard, ?; Jansen, G; Hoeijmakers, J H J; Nilsen, H; Vermeulen, W

2013-01-01

226

Telomerase-mediated life-span extension of human primary fibroblasts by human artificial chromosome (HAC) vector  

SciTech Connect

Telomerase-mediated life-span extension enables the expansion of normal cells without malignant transformation, and thus has been thought to be useful in cell therapies. Currently, integrating vectors including the retrovirus are used for human telomerase reverse transcriptase (hTERT)-mediated expansion of normal cells; however, the use of these vectors potentially causes unexpected insertional mutagenesis and/or activation of oncogenes. Here, we established normal human fibroblast (hPF) clones retaining non-integrating human artificial chromosome (HAC) vectors harboring the hTERT expression cassette. In hTERT-HAC/hPF clones, we observed the telomerase activity and the suppression of senescent-associated SA-{beta}-galactosidase activity. Furthermore, the hTERT-HAC/hPF clones continued growing beyond 120 days after cloning, whereas the hPF clones retaining the silent hTERT-HAC senesced within 70 days. Thus, hTERT-HAC-mediated episomal expression of hTERT allows the extension of the life-span of human primary cells, implying that gene delivery by non-integrating HAC vectors can be used to control cellular proliferative capacity of primary cultured cells.

Shitara, Shingo [Department of Biomedical Science, Institute of Regenerative Medicine and Biofunction, Graduate School of Medical Sciences, Tottori University, 86 Nishimachi, Yonago, Tottori 683-8503 (Japan); Kakeda, Minoru; Nagata, Keiko [Discovery Research Laboratories, Kirin Pharma Co., Ltd., 3 Miyahara-cho, Takasaki-shi, Gunma 370-1295 (Japan); Hiratsuka, Masaharu [Department of Biomedical Science, Institute of Regenerative Medicine and Biofunction, Graduate School of Medical Sciences, Tottori University, 86 Nishimachi, Yonago, Tottori 683-8503 (Japan); Sano, Akiko; Osawa, Kanako; Okazaki, Akiyo [Discovery Research Laboratories, Kirin Pharma Co., Ltd., 3 Miyahara-cho, Takasaki-shi, Gunma 370-1295 (Japan); Katoh, Motonobu; Kazuki, Yasuhiro; Oshimura, Mitsuo [Department of Biomedical Science, Institute of Regenerative Medicine and Biofunction, Graduate School of Medical Sciences, Tottori University, 86 Nishimachi, Yonago, Tottori 683-8503 (Japan); Tomizuka, Kazuma [Department of Biomedical Science, Institute of Regenerative Medicine and Biofunction, Graduate School of Medical Sciences, Tottori University, 86 Nishimachi, Yonago, Tottori 683-8503 (Japan); Discovery Research Laboratories, Kirin Pharma Co., Ltd., 3 Miyahara-cho, Takasaki-shi, Gunma 370-1295 (Japan)], E-mail: ktomizuka@kirin.co.jp

2008-05-09

227

Sex differences in the effects of cocaine abuse across the life span  

Microsoft Academic Search

Cocaine alters brain function from the early days of development throughout the entire life of an individual. Since the first preclinical research on cocaine sensitization was published, sex differences in response to the drug in adult rats have been noted. With the appearance of reports on crack babies during the 1980s, sex differences in response to prenatal (developmental) exposure have

Diana Dow-Edwards

2010-01-01

228

Empowerment: An Approach to Maintaining Dignity and Self-Esteem throughout the Life Span.  

ERIC Educational Resources Information Center

Notes that all individuals experience the aging process and that many associate aging with negative changes and decline. Contends that counselors must develop interventions that have a positive impact on the aging experience. Examines transitions of midlife and late life and proposes empowerment as a counseling strategy to help individuals meet

Schwiebert, Valerie L.; Giordano, Francesca G.

1994-01-01

229

Life Span as the Measure of Performance and Learning in a Business Gaming Simulation  

ERIC Educational Resources Information Center

This study applies the learning curve method of measuring learning to participants of a computer-assisted business gaming simulation that includes a multiple-life-cycle feature. The study involved 249 participants. It verified the workability of the feature and estimated the participants' rate of learning at 17.4% for every doubling of experience.

Thavikulwat, Precha

2012-01-01

230

Control across the life span: A model for understanding self-direction  

Microsoft Academic Search

A comprehensive four-factor interactive model on physical, psychological, and environmental processes related to the sense of control is presented for adult development with an emphasis on later life. The four experienced components are (1) control from within oneself, (2) control over oneself, (3) control over the environment, and (4) control from the environment. Control over oneself and over the environment

Donald W. Tiffany; Phyllis G. Tiffany

1996-01-01

231

Ethical Concerns in the Community About Technologies to Extend Human Life Span  

Microsoft Academic Search

Debates about the ethical and social implications of research that aims to extend human longevity by intervening in the ageing process have paid little attention to the attitudes of members of the general public. In the absence of empirical evidence, conflicting assumptions have been made about likely public attitudes towards life-extension. In light of recent calls for greater public involvement

Brad Partridge; Mair Underwood; Jayne Lucke; Helen Bartlett; Wayne Hall

2009-01-01

232

How single events change travel mode choice - a life span perspective  

Microsoft Academic Search

This paper reports the results of an explorative study with 91 German participants which was conducted in late 2003 as online-research with people between 19 and 62 years of age. Aim of the study was to test which events in life influence travel mode choice, how they influence it and if the psychology of predicting travel behaviour should focus more

C. A. Klckner

233

The Development of Memory Efficiency and Value-Directed Remembering Across the Life Span: A Cross-Sectional Study of Memory and Selectivity  

Microsoft Academic Search

Although attentional control and memory change considerably across the life span, no research has examined how the ability to strategically remember important information (i.e., value-directed remembering) changes from childhood to old age. The present study examined this in different age groups across the life span (N = 320, 596 years old). A selectivity task was used in which participants were

Alan D. Castel; Kathryn L. Humphreys; Steve S. Lee; Adriana Galvn; David A. Balota; David P. McCabe

2011-01-01

234

Life-long spontaneous exercise does not prolong lifespan but improves health span in mice  

PubMed Central

Background Life expectancy at birth in the first world has increased from 35 years at the beginning of the 20th century to more than 80 years now. The increase in life expectancy has resulted in an increase in age-related diseases and larger numbers of frail and dependent people. The aim of our study was to determine whether life-long spontaneous aerobic exercise affects lifespan and healthspan in mice. Results Male C57Bl/6J mice, individually caged, were randomly assigned to one of two groups: sedentary (n = 72) or spontaneous wheel-runners (n = 72). We evaluated longevity and several health parameters including grip strength, motor coordination, exercise capacity (VO2max) and skeletal muscle mitochondrial biogenesis. We also measured the cortical levels of the brain-derived neurotrophic factor (BDNF), a neurotrophin associated with brain plasticity. In addition, we measured systemic oxidative stress (malondialdehyde and protein carbonyl plasma levels) and the expression and activity of two genes involved in antioxidant defense in the liver (that is, glutathione peroxidase (GPx) and manganese superoxide dismutase (Mn-SOD)). Genes that encode antioxidant enzymes are considered longevity genes because their over-expression may modulate lifespan. Aging was associated with an increase in oxidative stress biomarkers and in the activity of the antioxidant enzymes, GPx and Mn-SOD, in the liver in mice. Life-long spontaneous exercise did not prolong longevity but prevented several signs of frailty (that is, decrease in strength, endurance and motor coordination). This improvement was accompanied by a significant increase in the mitochondrial biogenesis in skeletal muscle and in the cortical BDNF levels. Conclusion Life-long spontaneous exercise does not prolong lifespan but improves healthspan in mice. Exercise is an intervention that delays age-associated frailty, enhances function and can be translated into the clinic. PMID:24472376

2013-01-01

235

The frequency of voluntary and involuntary autobiographical memories across the life span  

Microsoft Academic Search

In the present study, ratings of the memory of an important event from the previous week on the frequency of voluntary and\\u000a involuntary retrieval, belief in its accuracy, visual imagery, auditory imagery, setting, emotional intensity, valence, narrative\\u000a coherence, and centrality to the life story were obtained from 988 adults whose ages ranged from 15 to over 90. Another 992\\u000a adults

David C. Rubin; Dorthe Berntsen

2009-01-01

236

The serotonin transporter gene and functional and pathological adaptation to environmental variation across the life span.  

PubMed

In analogy with the accepted view that behaviour is shaped by geneenvironment (GE) interactions, GE studies are exponentially increasing in the field of psychiatry. Whereas research was primarily driven by the premature view that negative environmental stimuli can trigger psychopathology in those subjects that are genetically predisposed, a closer look at the available data shows that GE interactions are much more complex than initially thought. Here, we discuss GE studies focussing on serotonin transporter (5-HTT, SERT, SLC6A4) gene variation in humans, monkeys, and rodents. Recent studies, across species, confirm the theorized 'for-better-and-for-worse' effect of low activity serotonin transporter genotypes. In addition, while 5-HTTE interactions were thought to take place in early life, recent evidence illustrates that these interactions are also manifested in adulthood. Therefore, we discuss data based on 5-HTTE interactions, and propose a model in which predictive adaptive responses (PARs), as shaped by early life 5-HTTE interactions, shape responses to environmental challenges in later life, i.e. reflecting 5-HTTEE interactions. PMID:22954594

Homberg, Judith R; van den Hove, Daniel L A

2012-11-01

237

Visualizing Life Zone Boundary Sensitivities Across Climate Models and Temporal Spans  

SciTech Connect

Life zones are a convenient and quantifiable method for delineating areas with similar plant and animal communities based on bioclimatic conditions. Such ecoregionalization techniques have proved useful for defining habitats and for studying how these habitats may shift due to environmental change. The ecological impacts of climate change are of particular interest. Here we show that visualizations of the geographic projection of life zones may be applied to the investigation of potential ecological impacts of climate change using the results of global climate model simulations. Using a multi-factor classification scheme, we show how life zones change over time based on quantitative model results into the next century. Using two straightforward metrics, we identify regions of high sensitivity to climate changes from two global climate simulations under two different greenhouse gas emissions scenarios. Finally, we identify how preferred human habitats may shift under these scenarios. We apply visualization methods developed for the purpose of displaying multivariate relationships within data, especially for situations that involve a large number of concurrent relationships. Our method is based on the concept of multivariate classification, and is implemented directly in VisIt, a production quality visualization package.

Sisneros, Roberto R [ORNL] [ORNL; Huang, Jian [University of Tennessee, Knoxville (UTK)] [University of Tennessee, Knoxville (UTK); Ostrouchov, George [ORNL] [ORNL; Hoffman, Forrest M [ORNL] [ORNL

2011-01-01

238

Evaluation of resveratrol, green tea extract, curcumin, oxaloacetic acid, and medium-chain triglyceride oil on life span of genetically heterogeneous mice.  

PubMed

The National Institute on Aging Interventions Testing Program (ITP) was established to evaluate agents that are hypothesized to increase life span and/or health span in genetically heterogeneous mice. Each compound is tested in parallel at three test sites. It is the goal of the ITP to publish all results, negative or positive. We report here on the results of lifelong treatment of mice, beginning at 4 months of age, with each of five agents, that is, green tea extract (GTE), curcumin, oxaloacetic acid, medium-chain triglyceride oil, and resveratrol, on the life span of genetically heterogeneous mice. Each agent was administered beginning at 4 months of age. None of these five agents had a statistically significant effect on life span of male or female mice, by log-rank test, at the concentrations tested, although a secondary analysis suggested that GTE might diminish the risk of midlife deaths in females only. PMID:22451473

Strong, Randy; Miller, Richard A; Astle, Clinton M; Baur, Joseph A; de Cabo, Rafael; Fernandez, Elizabeth; Guo, Wen; Javors, Martin; Kirkland, James L; Nelson, James F; Sinclair, David A; Teter, Bruce; Williams, David; Zaveri, Nurulain; Nadon, Nancy L; Harrison, David E

2013-01-01

239

Life History and Reproductive Biology of the Endangered Trillium reliquum  

Microsoft Academic Search

Knowledge of ecological characteristics of rare species is important in assessing their threat status. Trillium reliquum is one of four globally vulnerable North American Trillium species. Yet little is known about the ecology and reproductive biology of T. reliquum. Here we present the first description of the natural history and reproductive biology of T. reliquum. We observed the timing of

Christopher D. Heckel; Lissa M. Leege

2007-01-01

240

A transdisciplinary perspective of chronic stress in relation to psychopathology throughout life span development.  

PubMed

The allostatic load (AL) model represents an interdisciplinary approach to comprehensively conceptualize and quantify chronic stress in relation to pathologies throughout the life cycle. This article first reviews the AL model, followed by interactions among early adversity, genetics, environmental toxins, as well as distinctions among sex, gender, and sex hormones as integral antecedents of AL. We next explore perspectives on severe mental illness, dementia, and caregiving as unique human models of AL that merit future investigations in the field of developmental psychopathology. A complimenting transdisciplinary perspective is applied throughout, whereby we argue that the AL model goes beyond traditional stress-disease theories toward the advancement of person-centered research and practice that promote not only physical health but also mental health. PMID:21756430

Juster, Robert-Paul; Bizik, Gustav; Picard, Martin; Arsenault-Lapierre, Genevieve; Sindi, Shireen; Trepanier, Lyane; Marin, Marie-France; Wan, Nathalie; Sekerovic, Zoran; Lord, Catherine; Fiocco, Alexandra J; Plusquellec, Pierrich; McEwen, Bruce S; Lupien, Sonia J

2011-08-01

241

Diet-derived advanced glycation end products or lipofuscin disrupts proteostasis and reduces life span in Drosophila melanogaster.  

PubMed

Advanced glycation end product (AGE)-modified proteins are formed by the nonenzymatic glycation of free amino groups of proteins and, along with lipofuscin (a highly oxidized aggregate of covalently cross-linked proteins, sugars, and lipids), have been found to accumulate during aging and in several age-related diseases. As the in vivo effects of diet-derived AGEs or lipofuscin remain elusive, we sought to study the impact of oral administration of glucose-, fructose-, or ribose-modified albumin or of artificial lipofuscin in a genetically tractable model organism. We report herein that continuous feeding of young Drosophila flies with culture medium enriched in AGEs or in lipofuscin resulted in reduced locomotor performance and in accelerated rates of AGE-modified proteins and carbonylated proteins accumulation in the somatic tissues and hemolymph of flies, as well as in a significant reduction of flies health span and life span. These phenotypic effects were accompanied by reduced proteasome peptidase activities in both the hemolymph and the somatic tissues of flies and higher levels of oxidative stress; furthermore, oral administration of AGEs or lipofuscin in flies triggered an upregulation of the lysosomal cathepsin B, L activities. Finally, RNAi-mediated cathepsin D knockdown reduced flies longevity and significantly augmented the deleterious effects of AGEs and lipofuscin, indicating that lysosomal cathepsins reduce the toxicity of diet-derived AGEs or lipofuscin. Our in vivo studies demonstrate that chronic ingestion of AGEs or lipofuscin disrupts proteostasis and accelerates the functional decline that occurs with normal aging. PMID:23999505

Tsakiri, Eleni N; Iliaki, Kalliopi K; Hhn, Annika; Grimm, Stefanie; Papassideri, Issidora S; Grune, Tilman; Trougakos, Ioannis P

2013-12-01

242

Male personality, life-history strategies and reproductive success in a promiscuous mammal.  

PubMed

Recent theoretical work suggests that personality is a component of life history, but links between personality and either age-dependent reproductive success or life-history strategy are yet to be established. Using quantitative genetic analyses on a long-term pedigree we estimated indices of boldness and docility for 105 bighorn sheep rams (Ovis canadensis), born between 1983 and 1999, and compared these indices to their reproductive history from 2 years of age until death. Docility and boldness were highly heritable and negatively genetically correlated. Docile and bold rams survived longer than indocile and shy rams. Docility and boldness had a weak negative effect on reproductive success early in life, but a strong positive effect on older rams. Our findings highlight an important role of personality on reproductive success and suggest that personality could be an important component of life-history strategy. PMID:19555442

Rale, D; Martin, J; Coltman, D W; Poissant, J; Festa-Bianchet, M

2009-08-01

243

COPEPOD REPRODUCTIVE STRATEGIES: LIFE-HISTORY THEORY, PHYLOGENETIC PATTERN AND INVASION OF INLAND WATERS. (R824771)  

EPA Science Inventory

Abstract Life-history theory predicts that different reproductive strategies should evolve in environments that differ in resource availability, mortality, seasonality, and in spatial or temporal variation. Within a population, the predicted optimal strategy is driven ...

244

Aspects of the life history and reproductive biology of the worm Paraprionospio pinnata  

E-print Network

ASPECTS OF THE LIFE HISTORY AND REPRODUCTIVE BIOLOGY OF THE WORM PARAPRIONOSPIO PINNATA A Thesis by STEPHEN MANVILLE MAYFIELD Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements... for the degree MASTER OF SCIENCE December 1988 Major Subject: Zoolcgy ASPECTS OF THE LIFE HISTORY AND REPRODUCTIVE BIOLOGY OF THE WORM PARAPRIONOSPIO PINNATA A Thesis by STEPHEN MANVILLE MAYFIELD Approved as to style and content by: Donald E . Harper...

Mayfield, Stephen Manville

2012-06-07

245

Aging in the cerebellum and hippocampus and associated behaviors over the adult life span of CB6F1 mice  

PubMed Central

In the present study we examined the effects of normal aging in the hippocampus and cerebellum, as well as behaviors associated with these substrates. A total of 67 CB6F1 hybrid mice were tested at one of five ages (4, 8, 12, 18 or 25 months) on the context pre-exposure facilitation effect modification of fear conditioning (CPFE), rotorod, Barnes maze, acoustic startle, Morris water maze (MWM) and 500 ms trace eyeblink classical conditioning (EBCC). Behavioral tasks were chosen to increase the ability to detect age-related changes in learning, as trace EBCC is considered a more difficult paradigm (compared to delay EBCC) and the CPFE has been found to be more sensitive to hippocampus insults than standard contextual fear conditioning. To assess the effects of age on the brain, hippocampus volume was calculated and unbiased stereology was used to estimate the number of Purkinje neurons in the cerebellar cortex. A significant, age-related loss of Purkinje neurons was foundbeginning at 12 months of ageand hippocampus volume remained stable over the adult life span. Age-related impairment was found, beginning at 1218 months in the rotorod, and mice with fewer Purkinje neurons showed greater impairment in this task. CB6F1 mice retained auditory acuity across the life span and mice aged 25 months showed significant age-related impairment in the EBCC task; however, deficits were not associated with the loss of Purkinje neurons. Although the CPFE task is considered more sensitive to hippocampus insult, no age-related impairment was found. Spatial memory retention was impaired in the Barnes maze at 25 months, but no significant deficits were seen in the MWM. These results support the finding of differential aging in the hippocampus and cerebellum. PMID:23764510

Kennard, John A.; Brown, Kevin L.; Woodruff-Pak, Diana S.

2013-01-01

246

Metabolism, body size and life span: a case study in evolutionarily divergent populations of the garter snake (Thamnophis elegans).  

PubMed

We present a case study of metabolism, life history and aging in the western terrestrial garter snake (Thamnophis elegans). Early research in the field supported the rate-of-living hypothesis as an explanation of aging, which was based on an apparent negative relationship between mass-specific metabolic rate and lifespan in endotherms. This hypothesis in its original form has not withstood additional tests and comparisons between the two main lineages of endotherms-birds and mammals, but there is still much to be discovered of the causative links among rate of oxygen consumption, physiology and life history, particularly in ectothermic reptiles. We present data that show adult short-lived snakes, from naturally occurring ecotypes of garter snakes, have higher mass-specific resting metabolic rates at any given body mass (metabolic intensity) across a series of normal activity temperatures (15-32C). The short-lived ecotype in this geographic region reaches a larger body size, and has life-history traits that place it at the fast end of a pace-of-life continuum (fast growth, early maturation, high reproductive output) relative to individuals of the small-bodied long-lived ecotype. The difference between ecotypes in metabolic intensity, even after acclimation to identical conditions, may reflect evolutionary divergence and genetic differences between ecotypes. The difference in metabolic intensity is not, however, present at birth, so an alternative is that developmental environment may permanently influence metabolic rate and life history. Such developmental canalization could lead to altered gene expression via environmental influences on the epigenome and result in altered metabolic trajectories in the snakes' natural habitats. PMID:21558247

Bronikowski, Anne; Vleck, David

2010-11-01

247

ATM-dependent phosphorylation of SNEVhPrp19/hPso4 is involved in extending cellular life span and suppression of apoptosis  

PubMed Central

Defective DNA repair is widely acknowledged to negatively impact on healthy aging, since mutations in DNA repair factors lead to accelerated and premature aging. However, the opposite, namely if improved DNA repair will also increase the life or health span is less clear, and only few studies have tested if overexpression of DNA repair factors modulates life and health span in cells or organisms. Recently, we identified and characterized SNEVhPrp19/hPso4, a protein that plays a role in DNA repair and pre-mRNA splicing, and observed a doubling of the replicative life span upon ectopic overexpression, accompanied by lower basal DNA damage and apoptosis levels as well as an increased resistance to oxidative stress. Here we find that SNEVhPrp19/hPso4 is phosphorylated at S149 in an ataxia telangiectasia mutated protein (ATM)-dependent manner in response to oxidative stress and DNA double strand break inducing agents. By overexpressing wild-type SNEVhPrp19/hPso4 and a phosphorylation-deficient point-mutant, we found that S149 phosphorylation is necessary for mediating the resistance to apoptosis upon oxidative stress and is partially necessary for elongating the cellular life span. Therefore, ATM dependent phosphorylation of SNEVhPrp19/hPso4 upon DNA damage or oxidative stress might represent a novel axis capable of modulating cellular life span. PMID:22529335

Dellago, Hanna; Khan, Abdulhameed; Nussbacher, Monika; Gstraunthaler, Anna; Lammermann, Ingo; Schosserer, Markus; Muck, Christoph; Anrather, Dorothea; Scheffold, Annika; Ammerer, Gustav; Jansen-Durr, Pidder; Rudolph, Karl Lenhard; Voglauer-Grillari, Regina; Grillari, Johannes

2012-01-01

248

Effect of Ala-Glu-Asp-Gly peptide on life span and development of spontaneous tumors in female rats exposed to different illumination regimes.  

PubMed

The effects of Ala-Glu-Asp-Gly peptide (Epithalon) on the life span and development of spontaneous tumors were studied in female rats exposed to standard, natural for North-Western Russia, and constant illumination. The mean life span of animals exposed to constant or natural illumination decreased by 13.5 and 25.5%, the maximum by 9 and 7 months, respectively, and spontaneous tumors developed much more rapidly than in animals living under conditions of the standard light regimen. Epithalon (0.1 microg daily 5 times a week from the age of 4 months) did not change the life span of rats living under conditions of standard day/night regimen, while in rats exposed to the natural and constant light it promoted prolongation of the maximum life span by 95 and 24 days, respectively. Epithalon prolonged the mean life span of the last 10% of rats exposed to natural and constant illumination, treated with Epithalon, by 137 and 43 days, respectively. This peptide exhibited virtually no effect on the development of spontaneous tumors in rats exposed to standard and constant illumination, but significantly inhibited their development in rats exposed to natural light. PMID:18856211

Vinogradova, I A; Bukalev, A V; Zabezhinski, M A; Semenchenko, A V; Khavinson, V Kh; Anisimov, V N

2007-12-01

249

Implications of Extreme Life Span in Clonal Organisms: Millenary Clones in Meadows of the Threatened Seagrass Posidonia oceanica  

PubMed Central

The maximum size and age that clonal organisms can reach remains poorly known, although we do know that the largest natural clones can extend over hundreds or thousands of metres and potentially live for centuries. We made a review of findings to date, which reveal that the maximum clone age and size estimates reported in the literature are typically limited by the scale of sampling, and may grossly underestimate the maximum age and size of clonal organisms. A case study presented here shows the occurrence of clones of slow-growing marine angiosperm Posidonia oceanica at spatial scales ranging from metres to hundreds of kilometres, using microsatellites on 1544 sampling units from a total of 40 locations across the Mediterranean Sea. This analysis revealed the presence, with a prevalence of 3.5 to 8.9%, of very large clones spreading over one to several (up to 15) kilometres at the different locations. Using estimates from field studies and models of the clonal growth of P. oceanica, we estimated these large clones to be hundreds to thousands of years old, suggesting the evolution of general purpose genotypes with large phenotypic plasticity in this species. These results, obtained combining genetics, demography and model-based calculations, question present knowledge and understanding of the spreading capacity and life span of plant clones. These findings call for further research on these life history traits associated with clonality, considering their possible ecological and evolutionary implications. PMID:22312426

Arnaud-Haond, Sophie; Duarte, Carlos M.; Diaz-Almela, Elena; Marb, Nria; Sintes, Tomas; Serro, Ester A.

2012-01-01

250

Life Beyond the Eating Disorder: Education, Relationships, and Reproduction  

PubMed Central

Objective We investigated sociodemographic characteristics in women with and without lifetime eating disorders. Method Participants were from a multi-site international study of eating disorders (N = 2096). Education level, relationship status, and reproductive status were examined across eating disorder subtypes and compared with a healthy control group. Results Overall, women with eating disorders were less educated than controls, and duration of illness and age of onset were associated with educational attainment. Menstrual status was associated with both relationship and reproductive status, but eating disorder subtypes did not differ significantly from each other or from healthy controls on these dimensions. Conclusion Differences in educational attainment, relationships, and reproduction do exist in individuals with eating disorders and are differentially associated with various eating disorder symptoms and characteristics. These data could assist with educating patients and family members about long-term consequences of eating disorders. PMID:20143323

Maxwell, Millie; Thornton, Laura M.; Root, Tammy L.; Pinheiro, Andrea Poyastro; Strober, Michael; Brandt, Harry; Crawford, Steve; Crow, Scott; Fichter, Manfred M.; Halmi, Katherine A.; Johnson, Craig; Kaplan, Allan S.; Keel, Pamela; Klump, Kelly L.; LaVia, Maria; Mitchell, James E.; Plotnicov, Kathy; Rotondo, Alessandro; Woodside, D. Blake; Berrettini, Wade H.; Kaye, Walter H.; Bulik, Cynthia M.

2010-01-01

251

Human evolution, life history theory, and the end of biological reproduction.  

PubMed

Throughout primate history there have been three major life history transitions towards increasingly delayed sexual maturation and biological reproduction, as well as towards extended life expectancy. Monkeys reproduce later and live longer than do prosimians, apes reproduce later and live longer than do monkeys, and humans reproduce later and live longer than do apes. These life history transitions are connected to increased encephalization. During the last life history transition from apes to humans, increased encephalization co-evolved with increased dependence on cultural knowledge for energy acquisition. This led to a dramatic pressure for more energy investment in growth over current biological reproduction. Since the industrial revolution socioeconomic development has led to even more energy being devoted to growth over current biological reproduction. I propose that this is the beginning of an ongoing fourth major primate life history transition towards completely delayed biological reproduction and an extension of the evolved human life expectancy. I argue that the only fundamental difference between this primate life history transition and previous life history transitions is that this transition is being driven solely by cultural evolution, which may suggest some deeper evolutionary transition away from biological evolution is already in the process of occurring. PMID:24852016

Last, Cadell

2014-01-01

252

How Much Should We Weigh for a Long and Healthy Life Span? The Need to Reconcile Caloric Restriction versus Longevity with Body Mass Index versus Mortality Data  

PubMed Central

Total caloric restriction (CR) without malnutrition is a well-established experimental approach to extend life span in laboratory animals. Although CR in humans is capable of shifting several endocrinological parameters, it is not clear where the minimum inflection point of the U-shaped curve linking body mass index (BMI) with all-cause mortality lies. The exact trend of this curve, when used for planning preventive strategies for public health is of extreme importance. Normal BMI ranges from 18.5 to 24.9; many epidemiological studies show an inverse relationship between mortality and BMI inside the normal BMI range. Other studies show that the lowest mortality in the entire range of BMI is obtained in the overweight range (2529.9). Reconciling the extension of life span in laboratory animals by experimental CR with the BMImortality curve of human epidemiology is not trivial. In fact, one interpretation is that the CR data are identifying a known: excess fat is deleterious for health; although a second interpretation may be that: additional leanness from a normal body weight may add health and life span delaying the process of aging. This short review hope to start a discussion aimed at finding the widest consensus on which weight range should be considered the healthiest for our species, contributing in this way to the picture of what is the correct life style for a long and healthy life span. PMID:25126085

Lorenzini, Antonello

2014-01-01

253

Deterioration, death and the evolution of reproductive restraint in late life  

PubMed Central

Explaining why organisms schedule reproduction over their lifetimes in the various ways that they do is an enduring challenge in biology. An influential theoretical prediction states that organisms should increasingly invest in reproduction as they approach the end of their life. An apparent mismatch of empirical data with this prediction has been attributed to age-related constraints on the ability to reproduce. Here we present a general framework for the evolution of age-related reproductive trajectories. Instead of characterizing an organism by its age, we characterize it by its physiological condition. We develop a common currency that if maximized at each time guarantees the whole life history is optimal. This currency integrates reproduction, mortality and changes in condition. We predict that under broad conditions it will be optimal for organisms to invest less in reproduction as they age, thus challenging traditional interpretations of age-related traits and renewing debate about the extent to which observed life histories are shaped by constraint versus adaptation. Our analysis gives a striking illustration of the differences between an age-based and a condition-based approach to life-history theory. It also provides a unified account of not only standard life-history models but of related models involving the allocation of limited resources. PMID:19726476

McNamara, John M.; Houston, Alasdair I.; Barta, Zoltan; Scheuerlein, Alexander; Fromhage, Lutz

2009-01-01

254

Sodium Intake of Special Populations in the Healthy Aging in Neighborhoods of Diversity Across the Life Span (HANDLS) Study  

PubMed Central

Objective The sodium intake of participants of the Healthy Aging in Neighborhoods of Diversity across the Life Span study who were in three of the special population groups identified by the Dietary Guidelines for Americans, 2010 (those with hypertension, African Americans, and those ?51 years) was analyzed to determine if they met sodium recommendations. Methods The sample included 2152 African American and White subjects, aged 30-64 years. Major dietary sources of sodium for each group were determined from two 24-hour dietary recalls, and dietary intakes were compared with sodium recommendations. Dietary potassium was also evaluated. Results The intakes of the groups studied exceeded 1500 mg sodium while their potassium intakes were lower than the Adequate Intake of 4700 mg. The major contributors of sodium included cold cuts, sausage, and franks, protein foods, and yeast breads. Conclusions Excessive sodium intake characterized the diet of an urban, socioeconomically diverse population who are hypertensive or at risk for having hypertension. These findings have implications for health professionals and the food industry. PMID:23769900

Cotugna, Nancy; Fanelli-Kuczmarksi, Marie; Clymer, Julie; Hotchkiss, Lawrence; Zonderman, Alan B.; Evans, Michele K.

2013-01-01

255

A review of methionine dependency and the role of methionine restriction in cancer growth control and life-span extension.  

PubMed

Methionine is an essential amino acid with many key roles in mammalian metabolism such as protein synthesis, methylation of DNA and polyamine synthesis. Restriction of methionine may be an important strategy in cancer growth control particularly in cancers that exhibit dependence on methionine for survival and proliferation. Methionine dependence in cancer may be due to one or a combination of deletions, polymorphisms or alterations in expression of genes in the methionine de novo and salvage pathways. Cancer cells with these defects are unable to regenerate methionine via these pathways. Defects in the metabolism of folate may also contribute to the methionine dependence phenotype in cancer. Selective killing of methionine dependent cancer cells in co-culture with normal cells has been demonstrated using culture media deficient in methionine. Several animal studies utilizing a methionine restricted diet have reported inhibition of cancer growth and extension of a healthy life-span. In humans, vegan diets, which can be low in methionine, may prove to be a useful nutritional strategy in cancer growth control. The development of methioninase which depletes circulating levels of methionine may be another useful strategy in limiting cancer growth. The application of nutritional methionine restriction and methioninase in combination with chemotherapeutic regimens is the current focus of clinical studies. PMID:22342103

Cavuoto, Paul; Fenech, Michael F

2012-10-01

256

The ALS-associated proteins FUS and TDP-43 function together to affect Drosophila locomotion and life span.  

PubMed

The fatal adult motor neuron disease amyotrophic lateral sclerosis (ALS) shares some clinical and pathological overlap with frontotemporal dementia (FTD), an early-onset neurodegenerative disorder. The RNA/DNA-binding proteins fused in sarcoma (FUS; also known as TLS) and TAR DNA binding protein-43 (TDP-43) have recently been shown to be genetically and pathologically associated with familial forms of ALS and FTD. It is currently unknown whether perturbation of these proteins results in disease through mechanisms that are independent of normal protein function or via the pathophysiological disruption of molecular processes in which they are both critical. Here, we report that Drosophila mutants in which the homolog of FUS is disrupted exhibit decreased adult viability, diminished locomotor speed, and reduced life span compared with controls. These phenotypes were fully rescued by wild-type human FUS, but not ALS-associated mutant FUS proteins. A mutant of the Drosophila homolog of TDP-43 had similar, but more severe, deficits. Through cross-rescue analysis, we demonstrated that FUS acted together with and downstream of TDP-43 in a common genetic pathway in neurons. Furthermore, we found that these proteins associated with each other in an RNA-dependent complex. Our results establish that FUS and TDP-43 function together in vivo and suggest that molecular pathways requiring the combined activities of both of these proteins may be disrupted in ALS and FTD. PMID:21881207

Wang, Ji-Wu; Brent, Jonathan R; Tomlinson, Andrew; Shneider, Neil A; McCabe, Brian D

2011-10-01

257

[The role of clinical suicidology in the system of measures directed towards lowering early mortality and increasing population life span].  

PubMed

The level of early mortality has increased substantially in Russia within the last fifteen years, having exceeded the same parameter in developed countries and in the entire post-Soviet area. The second frequent reason for early mortality is a group of factors that includes accidents, suicides, murders, and other external causes. The proportion of suicides in this group is 45 to 50%. As a result, in the recent years the suicide rate in Russia has filled the second place in the world. The authors of this article analyze the suicide rate in different Russian regions, distinguishing between regions with the highest and lowest rate, and characterizing population risk factors of suicidal danger, a special place among which is filled by socioeconomic condition of the regions and the ethnic composition of their population. Increase of the effectiveness of suicide prevention depends on creation of adequate scientific basis, which clinical suicidology can become. The authors substantiate the necessity to distinguish suicidology as a separate field of clinical medicine, and formulate its definition, goals and objectives. Basing on the obtained results, the authors come to a conclusion on the medico-social importance of the development of clinical suicidology in lowering early mortality and increasing the country's population life span. PMID:17002021

Dmitrieva, T B; Polozhi?, B S

2006-01-01

258

Effect of rosmarinic acid in motor dysfunction and life span in a mouse model of familial amyotrophic lateral sclerosis.  

PubMed

Amyotrophic lateral sclerosis (ALS) is a late-onset progressive neurodegenerative disease affecting motor neurons. About 2% of patients with the disease are associated with mutations in the gene encoding Cu/Zn superoxide dismutase (SOD1). The purpose of this study is to assess the effect of rosemary extract and its major constituents, rosmarinic acid (RA) and carnosic acid (CA), in human SOD1 G93A transgenic mice, which are well-established mouse models for ALS. The present study demonstrates that intraperitoneal administration of rosemary extract or RA from the presymptomatic stage significantly delayed motor dysfunction in paw grip endurance tests, attenuated the degeneration of motor neurons, and extended the life span of ALS model mice. In addition, RA administration significantly improved the clinical score and suppressed body weight loss compared with a vehicle-treated group. In conclusion, this study provides the first report that rosemary extract and, especially, RA have preventive effects in the mouse model of ALS. PMID:19798750

Shimojo, Yosuke; Kosaka, Kunio; Noda, Yoshihiro; Shimizu, Takahiko; Shirasawa, Takuji

2010-03-01

259

Physical Attractiveness and Self-Esteem in Middle Childhood: Do Recent Life-Span Developmental Texts Perpetuate or Challenge Gender Stereotypes?  

ERIC Educational Resources Information Center

This document reports on an investigation focusing on how the content of introductory college psychology texts' content related to physical attractiveness and self-esteem. The primary objective of this study was to review how recently published life-span developmental texts present physical development in middle childhood as related to traditional

Hensley, Beth H.

260

Two regions of simian virus 40 large T-antigen independently extend the life span of primary C57BL/6 mouse embryo fibroblasts and cooperate in immortalization.  

PubMed

Expression of the SV40 large T-antigen allows primary cells to escape senescence and thereby become immortalized. Immortalization occurs in two steps, extension of life span and acquisition of unlimited cell division potential. By following the increase in expression of a senescence-associated marker with increased cell passage, we show that C57Bl/6 mouse embryo fibroblast (B6MEF) cultures senesce by passage 4. Thus, the development of colonies from cultures transfected with T-antigen expressing constructs indicates extension of life span. Two T-antigen regions independently extended the life span of B6MEF. Expression of either a T-antigen consisting of amino acids 1-147 (T1-147) or a T-antigen consisting of amino acids 251-708 (T251-708) resulted in colony development. However, the colonies expressing these truncated T-antigens could not be expanded into cell lines efficiently. In contrast, coexpression of T1-147 and T251-708 produced colonies that could be expanded into cell lines as efficiently as could colonies expressing full-length T-antigen. Thus, the two regions of T-antigen contain analogous activities that are sufficient to extend cell life span; they cooperate to immortalize primary B6MEF; and they act in trans, indicating that the functions involved are independent. PMID:9568030

Tevethia, M J; Lacko, H A; Conn, A

1998-04-10

261

Size of Family, Life Chances, and Reproductive Behavior.  

ERIC Educational Resources Information Center

Size of family of origin is more strongly related to wife's than husband's life chances. The mediating effect of allocation preferences on the number of siblings/life chances relationship carries through to the number of siblings/number of live-births relationship. (Author)

Zimmer, Basil G.; Fulton, John

1980-01-01

262

Life span extensions associated with upregulation of gene expression of antioxidant enzymes in Caenorhabditis elegans ; studies of mutation in the age-1 , PI3 kinase homologue and short-term exposure to hyperoxia  

Microsoft Academic Search

Life span could be modified by genetic or environmental perturbations in Caenorhabditis elegans. Here we show that two extensions of life span are associated with oxidative stress resistance and upregulation of the gene\\u000a expression of antioxidant enzymes. First, mutations in age-1 gene (PI3 kinase homologue)that confer life span extension, display oxidative stress resistance and increase in the gene\\u000a expression of

2002-01-01

263

A cost-benefit analysis of acclimation to low irradiance in tropical rainforest tree seedlings: leaf life span and payback time for leaf deployment  

PubMed Central

The maintenance in the long run of a positive carbon balance under very low irradiance is a prerequisite for survival of tree seedlings below the canopy or in small gaps in a tropical rainforest. To provide a quantitative basis for this assumption, experiments were carried out to determine whether construction cost (CC) and payback time for leaves and support structures, as well as leaf life span (i) differ among species and (ii) display an irradiance-elicited plasticity. Experiments were also conducted to determine whether leaf life span correlates to CC and payback time and is close to the optimal longevity derived from an optimization model. Saplings from 13 tropical tree species were grown under three levels of irradiance. Specific-CC was computed, as well as CC scaled to leaf area at the metamer level. Photosynthesis was recorded over the leaf life span. Payback time was derived from CC and a simple photosynthesis model. Specific-CC displayed only little interspecific variability and irradiance-elicited plasticity, in contrast to CC scaled to leaf area. Leaf life span ranged from 4 months to >26 months among species, and was longest in seedlings grown under lowest irradiance. It was always much longer than payback time, even under the lowest irradiance. Leaves were shed when their photosynthesis had reached very low values, in contrast to what was predicted by an optimality model. The species ranking for the different traits was stable across irradiance treatments. The two pioneer species always displayed the smallest CC, leaf life span, and payback time. All species displayed a similar large irradiance-elicited plasticity. PMID:21511904

Coste, Sabrina; Roggy, Jean-Christophe; Schimann, Heidy; Epron, Daniel; Dreyer, Erwin

2011-01-01

264

Malignant transformation of an infinite life span human fibroblast cell strain by transfection with v-Ki-ras.  

PubMed

To determine if human fibroblasts can be transformed into malignant cells by transfection of a K-ras oncogene, we transfected the provirus of Kirsten murine sarcoma virus (v-Ki-ras) into an infinite life span human cell strain, MSU-1.1, which has a normal morphology, is not anchorage independent, and has a stable, near-diploid karyotype. The transfected populations gave rise to distinct foci composed of morphologically-altered cells. The cells from several independent foci were isolated, propagated, and assayed for anchorage independence and/or tumorigenicity. They formed large-sized colonies in soft agar at a high frequency. Cell strains derived from colonies isolated from agar as well as focus-derived cell strains were injected subcutaneously into athymic mice to test for tumorigenicity. One cell strain yielded myxoid fibromas, the rest produced well-differentiated, progressively-growing, invasive, myxoid or spindle cell sarcomas. The karyotype of each of the cell strains tested, including cell strains derived from tumors, was identical to that of non-transfected MSU-1.1 cells. Two focus-derived strains, and two cell strains derived from sarcomas produced from them, were tested and shown by DNA and RNA hybridization to contain and express the v-Ki-ras oncogene. Radioimmunoprecipitation analysis showed that these strains expressed ras-specific p21 products not found in non-transfected MSU.1.1 cells. When injected intraperitoneally, a cell strain derived from a myxoid tumor gave rise to invasive myxoid tumors at various sites in the body. The same cell strain gave rise to invasive spindle cell sarcomas when injected into the tail vein of the animals. PMID:2216465

Fry, D G; Milam, L D; Dillberger, J E; Maher, V M; McCormick, J J

1990-09-01

265

Deletion of Brca2 exon 27 causes hypersensitivity to DNA crosslinks, chromosomal instability, and reduced life span in mice  

NASA Technical Reports Server (NTRS)

The Brca2 tumor-suppressor gene contributes to genomic stability, at least in part by a role in homologous recombinational repair. BRCA2 protein is presumed to function in homologous recombination through interactions with RAD51. Both exons 11 and 27 of Brca2 code for domains that interact with RAD51; exon 11 encodes eight BRC motifs, whereas exon 27 encodes a single, distinct interaction domain. Deletion of all RAD51-interacting domains causes embryonic lethality in mice. A less severe phenotype is seen with BRAC2 truncations that preserve some, but not all, of the BRC motifs. These mice can survive beyond weaning, but are runted and infertile, and die very young from cancer. Cells from such mice show hypersensitivity to some genotoxic agents and chromosomal instability. Here, we have analyzed mice and cells with a deletion of only the RAD51-interacting region encoded by exon 27. Mice homozygous for this mutation (called brca2(lex1)) have a shorter life span than that of control littermates, possibly because of early onsets of cancer and sepsis. No other phenotype was observed in these animals; therefore, the brca2(lex1) mutation is less severe than truncations that delete some BRC motifs. However, at the cellular level, the brca2(lex1) mutation causes reduced viability, hypersensitivity to the DNA interstrand crosslinking agent mitomycin C, and gross chromosomal instability, much like more severe truncations. Thus, the extreme carboxy-terminal region encoded by exon 27 is important for BRCA2 function, probably because it is required for a fully functional interaction between BRCA2 and RAD51. Copyright 2003 Wiley-Liss, Inc.

Donoho, Greg; Brenneman, Mark A.; Cui, Tracy X.; Donoviel, Dorit; Vogel, Hannes; Goodwin, Edwin H.; Chen, David J.; Hasty, Paul

2003-01-01

266

Evaluation of platelet thromboxane radioimmunoassay method to measure platelet life-span: Comparison with /sup 111/indium-platelet method  

SciTech Connect

The platelet activation during radiolabeling in vitro with Cr-51 and In-111 may affect the platelet life-span (PLS) in vivo. A new RIA method to measure PLS is being evaluated. Aspirin inhibits platelet thromboxane (TxA/sub 2/) by acetylating cyclooxygenase. The time required for the TxA/sub 2/ levels to return towards control values depends on the rate of new platelets entering circulation and is a measure of PLS. A single dose of aspirin (150mg) was given to 5 normal human subjects. Blood samples were collected for 2 days before aspirin and daily for 10 days. TxA/sub 2/ production in response to endogenous thrombin was studied by allowing 1 ml blood sample to clot at 37/sup 0/C for 90 min. Serum TxB/sub 2/ (stable breakdown product of Tx-A/sub 2/) levels determined by RIA technique. The plot of TxB/sub 2/ levels (% control) against time showed a gradual increase. The PLS calculated by linear regression analysis assuming a 2-day lag period before cyclooxygenase recovery is 9.7 +- 2.37. In the same 5 subjects, platelets from a 50ml blood sample were labeled with /sup 111/In-tropolone in 2 ml autologous plasma. Starting at 1 hr after injection of labeled platelets, 10 blood samples were obtained over a 8 day period. The PLS calculated based on a linear regression analysis is 10.2 +. 1.4. The PLS measured from the rate of platelet disappearance from circulation and the rate of platelet regeneration into circulation are quite comparable in normal subjects. TxA/sub 2/ regeneration RIA may provide a method to measure PLS without administering radioactivity to patient.

Vallabhajosula, S.; Machac, J.; Badimon, L.; Lipszyc, H.; Goldsmith, S.J.; Fuster, V.

1985-05-01

267

Changes in behaviors of male C57BL/6J mice across adult life span and effects of dietary restriction.  

PubMed

Behavioral analysis is a high-end read-out of aging impact on an organism, and here, we have analyzed behaviors in 4-, 22-, and 28-month-old male C57BL/6J with a broad range of tests. For comparison, a group of 28-month-old males maintained on dietary restriction (DR) was included. The most conspicuous alteration was the decline in exploration activity with advancing age. Aging also affected other behaviors such as motor skill acquisition and grip strength, in contrast to latency to thermal stimuli and visual placement which were unchanged. Object recognition tests revealed intact working memory at 28 months while memory recollection was impaired already at 22 months. Comparison with female C57BL/6J (Fahlstrm et al., Neurobiol Aging 32:1868-1880, 2011) revealed that alterations in aged males and females are similar and that several of the behavioral indices correlate with age in both sexes. Moreover, we examined if behavioral indices in 22-month-old males could predict remaining life span as suggested in the study by Ingram and Reynolds (Exp Aging Res 12(3):155-162, 1986) and found that exploratory activity and motor skills accounted for up to 65% of the variance. Consistent with that a high level of exploratory activity and preserved motor capacity indicated a long post-test survival, 28-month-old males maintained on DR were more successful in such tests than ad libitum fed age-matched males. In summary, aged C57BL/6J males are marked by a reduced exploratory activity, an alteration that DR impedes. In light of recently published data, we discuss if a diminishing drive to explore may associate with aging-related impairment of central aminergic pathways. PMID:21989972

Fahlstrm, Andreas; Zeberg, Hugo; Ulfhake, Brun

2012-12-01

268

Radiation exposure and the risk of mortality from noncancer respiratory diseases in the life span study, 1950-2005.  

PubMed

An apparent association between radiation exposure and noncancer respiratory diseases (NCRD) in the Life Span Study (LSS) of atomic bomb survivors has been reported, but the biological validity of that observation is uncertain. This study investigated the possibility of radiation causation of noncancer respiratory diseases in detail by examining subtypes of noncancer respiratory diseases, temporal associations, and the potential for misdiagnosis and other confounding factors. A total of 5,515 NCRD diagnoses listed as the underlying cause of death on the death certificate were observed among the 86,611 LSS subjects with estimated weighted absorbed lung doses. Radiation dose-response analyses were conducted using Cox proportional hazard regression for pneumonia/influenza, other acute respiratory infections, chronic obstructive pulmonary disease and asthma. The linear excess relative risks (ERR) per gray (Gy) were 0.17 (95% CI 0.08, 0.27) for all NCRD and 0.20 (CI 0.09, 0.34) for pneumonia/influenza, which accounted for 63% of noncancer respiratory disease deaths. Adjustments for lifestyle and sociodemographic variations had almost no impact on the risk estimates. However, adjustments for indications of cancer and/or cardiovascular disease decreased the risk estimates, with ERR for total noncancer respiratory diseases declined by 35% from 0.17 to 0.11. Although it was impossible to fully adjust for the misdiagnosis of other diseases as noncancer respiratory diseases deaths in this study because of limitations of available data, nevertheless, the associations were reduced or eliminated by the adjustment that could be made. This helps demonstrates that the association between noncancer respiratory diseases and radiation exposure in previous reports could be in part be attributed to coincident cancer and/or cardiovascular diseases. PMID:24148011

Pham, Truong-Minh; Sakata, Ritsu; Grant, Eric J; Shimizu, Yukiko; Furukawa, Kyoji; Takahashi, Ikuno; Sugiyama, Hiromi; Kasagi, Fumiyoshi; Soda, Midori; Suyama, Akihiko; Shore, Roy E; Ozasa, Kotaro

2013-11-01

269

Reproduction and early life history of northern squawfish, Ptychocheilus oregonensis , in Idaho's St. Joe River  

Microsoft Academic Search

Synopsis Reproduction and early life history of northern squawfish,Ptychocheilus oregonensis, was investigated in Idaho's St. Joe River from 19801981. Spawning occurs in large aggregations which mill near the substrate to broadcast eggs and milt. Males greatly outnumber females in the aggregations. Males mature at smaller sizes and younger ages, and exhibit slower growth and greater mortality than females, although females

Raymond C. Beamesderfer

1992-01-01

270

Positive Regulation of DNA Double Strand Break Repair Activity during Differentiation of Long Life Span Cells: The Example of Adipogenesis  

PubMed Central

Little information is available on the ability of terminally differentiated cells to efficiently repair DNA double strand breaks (DSBs), and one might reasonably speculate that efficient DNA repair of these threatening DNA lesions, is needed in cells of long life span with no or limited regeneration from precursor. Few tissues are available besides neurons that allow the study of DNA DSBs repair activity in very long-lived cells. Adipocytes represent a suitable model since it is generally admitted that there is a very slow turnover of adipocytes in adult. Using both Pulse Field Gel Electrophoresis (PFGE) and the disappearance of the phosphorylated form of the histone variant H2AX, we demonstrated that the ability to repair DSBs is increased during adipocyte differentiation using the murine pre-adipocyte cell line, 3T3F442A. In mammalian cells, DSBs are mainly repaired by the non-homologous end-joining pathway (NHEJ) that relies on the DNA dependent protein kinase (DNA-PK) activity. During the first 24 h following the commitment into adipogenesis, we show an increase in the expression and activity of the catalytic sub-unit of the DNA-PK complex, DNA-PKcs. The increased in DNA DSBs repair activity observed in adipocytes was due to the increase in DNA-PK activity as shown by the use of DNA-PK inhibitor or sub-clones of 3T3F442A deficient in DNA-PKcs using long term RNA interference. Interestingly, the up-regulation of DNA-PK does not regulate the differentiation program itself. Finally, similar positive regulation of DNA-PKcs expression and activity was observed during differentiation of primary culture of pre-adipocytes isolated from human sub-cutaneous adipose tissue. Our results show that DNA DSBs repair activity is up regulated during the early commitment into adipogenesis due to an up-regulation of DNA-PK expression and activity. In opposition to the general view that DNA DSBs repair is decreased during differentiation, our results demonstrate that an up-regulation of this process might be observed in post-mitotic long-lived cells. PMID:18846213

Meulle, Aline; Salles, Bernard; Daviaud, Daniele; Valet, Philippe; Muller, Catherine

2008-01-01

271

The role of early life nutrition in programming of reproductive function.  

PubMed

Accumulating evidence suggest that the concept of programming can also be applied to reproductive development and function, representing an ever expanding research area. Recently issues such as peri- or even preconceptional nutrition, transgenerational effects and underlying mechanisms have received considerable attention. The present chapter presents the existed evidence and reviews the available data from numerous animal and human studies on the effects of early life nutritional environment on adult reproductive function. Specific outcomes depend on the severity, duration and stage of development when nutritional perturbations are imposed, while sex-specific effects are also manifested. Apart from undernutrition, effects of relative overnutrition as well as the complex interactions between pre- and postnatal nutrition is of high importance, especially in the context of our days obesity epidemic. Mechanisms underlying reproductive programming are yet unclear, but may include a role for epigenetic modifications. Epigenetic modulation of critical genes involved in the control of reproductive function and potential intergenerational effects represent an exciting area of interdisciplinary research toward the development of new nutritional approaches during pre- and postnatal periods to ensure reproductive health in later life. PMID:24847686

Chadio, S; Kotsampasi, B

2014-02-01

272

Influence of Individualism-Collectivism on Learning Barriers and Self-Efficacy of Performance Ratings in an Introductory Life-Span Development Course  

Microsoft Academic Search

The influence of individualism-collectivism on perceived learning barriers and self- efficacy of course performance was examined. Subjects included 103 students enrolled in an Introduction to Life-span Development course. Participants were administered a survey at the end of the fourth week of the semester that contained demographic measures, an index of individualism-collectivism, as well as items assessing learning barriers and self-efficacy.

Dean D. VonDras

273

Differential longitudinal changes in cortical thickness, surface area and volume across the adult life span: regions of accelerating and decelerating change.  

PubMed

Human cortical thickness and surface area are genetically independent, emerge through different neurobiological events during development, and are sensitive to different clinical conditions. However, the relationship between changes in the two over time is unknown. Additionally, longitudinal studies have almost invariably been restricted to older adults, precluding the delineation of adult life span trajectories of change in cortical structure. In this longitudinal study, we investigated changes in cortical thickness, surface area, and volume after an average interval of 3.6 years in 207 well screened healthy adults aged 23-87 years. We hypothesized that the relationships among metrics are dynamic across the life span, that the primary contributor to cortical volume reductions in aging is cortical thinning, and that magnitude of change varies with age and region. Changes over time were seen in cortical area (mean annual percentage change [APC], -0.19), thickness (APC, -0.35), and volume (APC, -0.51) in most regions. Volume changes were primarily explained by changes in thickness rather than area. A negative relationship between change in thickness and surface area was found across several regions, where more thinning was associated with less decrease in area, and vice versa. Accelerating changes with increasing age was seen in temporal and occipital cortices. In contrast, decelerating changes were seen in prefrontal and anterior cingulate cortices. In conclusion, a dynamic relationship between cortical thickness and surface area changes exists throughout the adult life span. The mixture of accelerating and decelerating changes further demonstrates the importance of studying these metrics across the entire adult life span. PMID:24948804

Storsve, Andreas B; Fjell, Anders M; Tamnes, Christian K; Westlye, Lars T; Overbye, Knut; Aasland, Hilde W; Walhovd, Kristine B

2014-06-18

274

Genetic Modifiers of the Drosophila Blue Cheese Gene Link Defects in Lysosomal Transport With Decreased Life Span and Altered Ubiquitinated-Protein Profiles  

Microsoft Academic Search

Defects in lysosomal trafficking pathways lead to decreased cell viability and are associated with progressive disorders in humans. Previously we have found that loss-of-function (LOF) mutations in the Drosophila gene blue cheese (bchs) lead to reduced adult life span, increased neuronal death, and widespread CNS degeneration that is associated with the formation of ubiquitinated-protein aggregates. To identify potential genes that

Anne Simonsen; Robert C. Cumming; Karine Lindmo; Vanessa Galaviz; Susan Cheng; Tor Erik Rusten; Kim D. Finley

2007-01-01

275

Global Self-Esteem Across the Life Span: A Cross-Sectional Comparison Between Representative and Self-Selected Internet Samples  

Microsoft Academic Search

The cross-sectional trajectory of global self-esteem across the life span was examined administering the Rosenberg and Single-Item Self-Esteem scales to Estonians (N=29,463) who were either randomly selected from the National Census to represent the population or self-recruited through the Internet. The results (a) challenge the recent conclusion of a universal age trajectory of self-esteem, (b) demonstrate that self-recruited Internet data

Helle Pullmann; Jri Allik; Anu Realo

2009-01-01

276

Differential reproductive responses to stress reveal the role of life-history strategies within a species  

PubMed Central

Life-history strategies describe that slow- in contrast to fast-living species allocate resources cautiously towards reproduction to enhance survival. Recent evidence suggests that variation in strategies exists not only among species but also among populations of the same species. Here, we examined the effect of experimentally induced stress on resource allocation of breeding seabirds in two populations with contrasting life-history strategies: slow-living Pacific and fast-living Atlantic black-legged kittiwakes. We tested the hypothesis that reproductive responses in kittiwakes under stress reflect their life-history strategies. We predicted that in response to stress, Pacific kittiwakes reduce investment in reproduction compared with Atlantic kittiwakes. We exposed chick-rearing kittiwakes to a short-term (3-day) period of increased exogenous corticosterone (CORT), a hormone that is released during food shortages. We examined changes in baseline CORT levels, parental care and effects on offspring. We found that kittiwakes from the two populations invested differently in offspring when facing stress. In response to elevated CORT, Pacific kittiwakes reduced nest attendance and deserted offspring more readily than Atlantic kittiwakes. We observed lower chick growth, a higher stress response in offspring and lower reproductive success in response to CORT implantation in Pacific kittiwakes, whereas the opposite occurred in the Atlantic. Our findings support the hypothesis that life-history strategies predict short-term responses of individuals to stress within a species. We conclude that behaviour and physiology under stress are consistent with trade-off priorities as predicted by life-history theory. We encourage future studies to consider the pivotal role of life-history strategies when interpreting inter-population differences of animal responses to stressful environmental events. PMID:24089339

Schultner, J.; Kitaysky, A. S.; Gabrielsen, G. W.; Hatch, S. A.; Bech, C.

2013-01-01

277

Seven Questions about the WAIS-III Regarding Differences in Abilities across the 16 to 89 Year Life Span.  

ERIC Educational Resources Information Center

Data from the Wechsler Adult Intelligence Scale-Third Edition (WAIS-III) manual and data provided by the test publisher were analyzed to address seven questions about differences in human cognitive abilities as they are measured by the WAIS-III across the 16-89 year age span. All seven questions were of a practical, clinical nature. (Author/MKA)

Kaufman, Alan S.

2000-01-01

278

Care and the self: biotechnology, reproduction, and the good life  

PubMed Central

This paper explores a novel philosophy of ethical care in the face of burgeoning biomedical technologies. I respond to a serious challenge facing traditional bioethics with its roots in analytic philosophy. The hallmarks of these traditional approaches are reason and autonomy, founded on a belief in the liberal humanist subject. In recent years, however, there have been mounting challenges to this view of human subjectivity, emerging from poststructuralist critiques, such as Michel Foucault's, but increasingly also as a result of advances in biotechnology itself. In the face of these developments, I argue that the theoretical relevance and practical application of mainstream bioethics is increasingly under strain. Traditionalists will undoubtedly resist. Together, professional philosopher-bioethicists, public health policymakers, and the global commercial healthcare industry tend to respond conservatively by shoring up the liberal humanist subject as the foundation for medical ethics and consumer decision-making, appealing to the familiar tropes of reason, autonomy, and freedom. I argue for a different approach to bioethics, and work towards a new way to conceive of ethical relations in healthcare one that does not presume a sovereign subject as the basis of dignity, personhood or democracy. Instead, I am critical of the narrow instantiations of reason, autonomy, and freedom, which, more recently, have been co-opted by a troubling neo-liberal politics of the self. Thus, I am critical of current trends in medical ethics, often running in tandem with corporate-governmental models of efficiency, accountability, and so-called evidence-based best practices. As an example of such market-driven conceptions of subjectivity, I discuss the paradigm of "self-care." Self-care shores up the traditional view of the self as a free agent. In this sense, self-care is looked upon favourably by mainstream bioethics in its focus on autonomy, while healthcare policy endorses this model for ideological and economic reasons. To contrast this, I propose a different model of care together with a different model of selfhood. Here I develop and apply Foucault's late work on the "care of the self." In this understanding of "care," I suggest that we might work towards an ethical self that is more commensurable both with recent theoretical views on subjectivity and more pressingly with the challenges of emergent biotechnologies. I end this paper with a discussion on ethical parenthood, which offers a practical reading of the "care of the self" in relation to new reproductive technologies (NRTs). PMID:17480234

Murray, Stuart J

2007-01-01

279

Environmental contingency in life history strategies: the influence of mortality and socioeconomic status on reproductive timing.  

PubMed

Why do some people have children early, whereas others delay reproduction? By considering the trade-offs between using one's resources for reproduction versus other tasks, the evolutionary framework of life history theory predicts that reproductive timing should be influenced by mortality and resource scarcity. A series of experiments examined how mortality cues influenced the desire to have children sooner rather than later. The effects of mortality depended critically on whether people grew up in a relatively resource-scarce or resource-plentiful environment. For individuals growing up relatively poor, mortality cues produced a desire to reproduce sooner--to want children now, even at the cost of furthering one's education or career. Conversely, for individuals growing up relatively wealthy, mortality cues produced a desire to delay reproduction--to further one's education or career before starting a family. Overall, mortality cues appear to shift individuals into different life history strategies as a function of childhood socioeconomic status, suggesting important implications for how environmental factors can influence fertility and family size. PMID:20873933

Griskevicius, Vladas; Delton, Andrew W; Robertson, Theresa E; Tybur, Joshua M

2011-02-01

280

Systematic review of gamma-aminobutyric-acid inhibitory deficits across the reproductive life cycle.  

PubMed

Deficiencies in the inhibitory functioning of gamma-aminobutyric acid (GABA) have been implicated in the pathophysiology of depressive disorders. Reproductive life cycle events, including menstruation, pregnancy, and menopause, are consistently associated with increased psychopathology, in particular mood disorders. Given that GABA-inhibitory activity may be modulated directly or indirectly by estrogen, progesterone, and their metabolites receptors, it has been hypothesized that GABA deficits may be evident during these reproductive periods. We aimed to compare GABA function among women during these "high-risk" reproductive periods to GABA function among women at other time periods. We conducted a systematic review of studies comparing women during reproductive life stages associated with depressive disorder risk (luteal phase of the menstrual cycle, perinatal period, and menopausal transition) to women at other time periods. The study outcome was GABA function. The review included 11 studies, 9 focused on the menstrual cycle, and 2 focused on the perinatal period. GABA-inhibitory function fluctuated across the menstrual cycle, with differing patterns in women with and without depressive disorders. GABA-inhibitory function was reduced in pregnancy and early postpartum compared to the nonpregnant state. Key limitations were the absence of studies evaluating the menopausal transition, and the heterogeneity of GABA outcome measures. GABA-inhibitory function fluctuates across the menstrual cycle and is reduced perinatally. This has potential implications for a role of GABAergically mediated interventions in the prevention and treatment of menstrual cycle-related and perinatal depressive disorders. PMID:24420415

Vigod, Simone N; Strasburg, Kate; Daskalakis, Zafiris J; Blumberger, Daniel M

2014-04-01

281

Environmental Contingency in Life History Strategies: The Influence of Mortality and Socioeconomic Status on Reproductive Timing  

PubMed Central

Why do some people have children early, whereas others delay reproduction? By considering the trade-offs between using ones resources for reproduction versus other tasks, the evolutionary framework of life history theory predicts that reproductive timing should be influenced by mortality and resource scarcity. A series of experiments examined how mortality cues influenced the desire to have children sooner rather than later. The effects of mortality depended critically on whether people grew up in a relatively resource-scarce or resource-plentiful environment. For individuals growing up relatively poor, mortality cues produced a desire to reproduce soonerto want children now, even at the cost of furthering ones education or career. Conversely, for individuals growing up relatively wealthy, mortality cues produced a desire to delay reproductionto further ones education or career before starting a family. Overall, mortality cues appear to shift individuals into different life history strategies as a function of childhood socioeconomic status, suggesting important implications for how environmental factors can influence fertility and family size. PMID:20873933

Griskevicius, Vladas; Delton, Andrew W.; Robertson, Theresa E.; Tybur, Joshua M.

2013-01-01

282

The reproductive cycle and life history of the Arctic copepod Calanus glacialis in the White Sea  

Microsoft Academic Search

Seasonal variations in the gonad development and sex ratio of copepodite stage V (CV) and adults were examined from February\\u000a to November in order to understand the reproductive cycle and the life history of Calanus glacialis in the White Sea. Gonad maturation, sexual differentiation and moulting to adults take place during the 2nd year of development.\\u000a Energy accumulation takes place

K. N. Kosobokova

1999-01-01

283

Variation in Male Reproductive Longevity across Traditional Societies  

PubMed Central

Most accounts of human life history propose that women have short reproductive spans relative to their adult lifespans, while men not only remain fertile but carry on reproducing until late life. Here we argue that studies have overlooked evidence for variation in male reproductive ageing across human populations. We apply a Bayesian approach to census data from Agta hunter-gatherers and Gambian farmers to show that long post-reproductive lifespans characterise not only women but also males in some traditional human populations. We calculate three indices of reproductive ageing in men (oldest age at reproduction, male late-life reproduction, and post-reproductive representation) and identify a continuum of male reproductive longevity across eight traditional societies ranging from !Kung, Hadza and Agta hunter-gatherers exhibiting low levels of polygyny, early age at last reproduction and long post-reproductive lifespans, to male Gambian agriculturalists and Turkana pastoralists showing higher levels of polygyny, late-life reproduction and shorter post-reproductive lifespans. We conclude that the uniquely human detachment between rates of somatic senescence and reproductive decline, and the existence of post-reproductive lifespans, are features of both male and female life histories, and therefore not exclusive consequences of menopause. PMID:25405763

Vinicius, Lucio; Mace, Ruth; Migliano, Andrea

2014-01-01

284

Life Table Evaluation of Survival and Reproduction of the Aphid, Sitobion avenae, Exposed to Cadmium  

PubMed Central

The effects of cadmium (Cd) on the development, fecundity, and reproduction of the grain aphid, Sitobion avenae Fabricius (Hemiptera: Aphididae) were estimated by constructing a life table of S. avenae exposed to Cd. The concentrations of Cd in the soil were as follows: 0, 10, 20, 40, 80, and 160 mg/kg. The correlation analysis of the Cd concentration in soil and wheat revealed that the amount in the wheat increased with the increase of Cd concentrations in soil. The results indicated that, the latter part of the reproduction period was significantly affected by Cd, according to the curve of the total survival rate (lx). The net reproductive rate (R 0), innate capacity of increase (r), and finite rate of increase (?) of S. avenae all decreased under the stress of Cd, and were lowest at a Cd concentration of 20 mg/kg. Cd also negatively affected fecundity and mx (the number of offspring produced by an individual female). At 20 mg/kg, the decline of them was most obvious. In conclusion, survival and reproduction of S. avenae were inhibited under the treatment of the heavy metal Cd. Sitobion avenae was more sensitive to Cd at concentration of 20 mg/kg compared to the other concentrations. This concentration can be used to examine the mechanisms behind population genetics and biological mutation of S. avenae when exposed to heavy metal. PMID:22958415

Gao, Huan-Huan; Zhao, Hui-Yan; Du, Chao; Deng, Ming-Ming; Du, Er-Xia; Hu, Zu-Qing; Hu, Xiang-Shun

2012-01-01

285

Older Motherhood and the Changing Life Course in the Era of Assisted Reproductive Technologies  

PubMed Central

Midlife, once a focus of particular interest to gerontologists because of its implications for later life, has recently received little attention. But as new reproductive technologies have expanded in the United States, motherhood is occurring at older ages. While older motherhood is not a new social practice, what is unique is that an increasing number of women are becoming pregnant through technological means, often for the first time, at the end of their reproductive cycle. These women can be understood as part of a new middle age, engaging in new life course possibilities that respond to changing social, cultural, physical, and economic realities, and potentially extending much later in the life course. Drawing on interviews with 79 couples, we utilize symbolic interactionist conceptualizations of identity and stigma to consider how women negotiate the shifting social identities associated with older motherhood. We conclude that older motherhood will be one phenomenon contributing to an enduring change in views of what constitutes old age, and that it will be seen as occurring much later in the life course. PMID:18443646

Friese, Carrie; Becker, Gay; Nachtigall, Robert D.

2008-01-01

286

[Influence of ischemic heart disease mortality on the average life span in Bulgaria and economic results of this disease].  

PubMed

The paper provides a socio-economic evaluation of mortality from ischemic heart disease (IHD) in Bulgaria during 1983-1985. The influence of IHD on mean life expectancy at birth was determined by using concise methods. IHD shortens the mean life expectancy in urban areas by 2.4 years in boys and by 1.7 years in girls, in rural areas by 2.5 years in boys and by 1.2 in girls. Economic losses due to mortality from this disease were estimated. PMID:2057826

Nikolov, I N

1991-01-01

287

SHC-1/p52Shc targets the insulin/IGF-1 and JNK signaling pathways to modulate life span and stress response in C. elegans  

PubMed Central

Correlative evidence links stress, accumulation of oxidative cellular damage, and aging in several species. Genetic studies in species ranging from yeast to mammals revealed several pathways regulating stress response and life span, including caloric intake, mitochondrial respiration, insulin/IGF-1 (IIS), and JNK (c-Jun N-terminal kinase) signaling. How IIS and JNK signaling cross-talk to defend against diverse stressors contributing to aging is of critical importance but, so far, only poorly understood. In this study, we demonstrate that the adaptor protein SHC-1, the Caenorhabditis elegans homolog of human p52Shc, coordinates mechanisms of stress response and aging. Using genetic and biochemical approaches, we discover that SHC-1 not only opposes IIS but also activates JNK signaling. Loss of shc-1 function results in accelerated aging and enhanced sensitivity to heat, oxidative stress, and heavy metals, whereas expression of human p52Shc rescues the shc-1 mutant phenotype. SHC-1 acts upstream of the insulin/IGF receptor DAF-2 and the PI3 kinase AGE-1 and directly interacts with DAF-2. Moreover, SHC-1 activates JNK signaling by binding to MEK-1 kinase. Both aspects converge on controlling the nuclear translocation and activation of the FOXO transcription factor DAF-16. Our findings establish C. elegans SHC-1 as a critical scaffold that directly cross-connects the two parallel JNK and IIS pathways and help to explain how these signaling cascades cooperate to ascertain normal stress response and life span in C. elegans. PMID:18832074

Neumann-Haefelin, Elke; Qi, Wenjing; Finkbeiner, Elisabeth; Walz, Gerd; Baumeister, Ralf; Hertweck, Maren

2008-01-01

288

Extracts of Cistanche deserticola Can Antagonize Immunosenescence and Extend Life Span in Senescence-Accelerated Mouse Prone 8 (SAM-P8) Mice.  

PubMed

The senescence accelerated mouse prone 8 substrain (SAM-P8), widely accepted as an animal model for studying aging and antiaging drugs, was used to examine the effects of dietary supplementation with extracts of Cistanche deserticola (ECD) which has been used extensively in traditional Chinese medicine because of its perceived ability to promote immune function in the elderly. Eight-month-old male SAM-P8 mice were treated with ECD by daily oral administrations for 4 weeks. The results showed that dietary supplementation of 150?mg/kg and 450?mg/kg of ECD could extend the life span measured by Kaplan-Meier survival analysis in dose-dependent manner. Dietary supplementation of SAM-P8 mice for 4 weeks with 100, 500, and 2500?mg/kg of ECD was shown to result in significant increases in both naive T and natural killer cells in blood and spleen cell populations. In contrast, peripheral memory T cells and proinflammatory cytokine, IL-6 in serum, were substantially decreased in the mice that ingested 100 and 500?mg/kg of ECD daily. Additionally, Sca-1 positive cells, the recognized progenitors of peripheral naive T cells, were restored in parallel. Our results provide clear experimental support for long standing clinical observational studies showing that Cistanche deserticola possesses significant effects in extending life span and suggest this is achieved by antagonizing immunosenescence. PMID:24523825

Zhang, Ke; Ma, Xu; He, Wenjun; Li, Haixia; Han, Shuyan; Jiang, Yong; Wu, Hounan; Han, Li; Ohno, Tomohiro; Uotsu, Nobuo; Yamaguchi, Kohji; Ma, Zhizhong; Tu, Pengfei

2014-01-01

289

Budding Yeast SSD1-V Regulates Transcript Levels of Many Longevity Genes and Extends Chronological Life Span in Purified Quiescent Cells  

PubMed Central

Ssd1 is an RNA-binding protein that affects literally hundreds of different processes and is polymorphic in both wild and lab yeast strains. We have used transcript microarrays to compare mRNA levels in an isogenic pair of mutant (ssd1-d) and wild-type (SSD1-V) cells across the cell cycle. We find that 15% of transcripts are differentially expressed, but there is no correlation with those mRNAs bound by Ssd1. About 20% of cell cycle regulated transcripts are affected, and most show sharper amplitudes of oscillation in SSD1-V cells. Many transcripts whose gene products influence longevity are also affected, the largest class of which is involved in translation. Ribosomal protein mRNAs are globally down-regulated by SSD1-V. SSD1-V has been shown to increase replicative life span and we show that SSD1-V also dramatically increases chronological life span (CLS). Using a new assay of CLS in pure populations of quiescent prototrophs, we find that the CLS for SSD1-V cells is twice that of ssd1-d cells. PMID:19570907

Li, Lihong; Lu, Yong; Qin, Li-Xuan; Bar-Joseph, Ziv; Werner-Washburne, Margaret

2009-01-01

290

Extracts of Cistanche deserticola Can Antagonize Immunosenescence and Extend Life Span in Senescence-Accelerated Mouse Prone 8 (SAM-P8) Mice  

PubMed Central

The senescence accelerated mouse prone 8 substrain (SAM-P8), widely accepted as an animal model for studying aging and antiaging drugs, was used to examine the effects of dietary supplementation with extracts of Cistanche deserticola (ECD) which has been used extensively in traditional Chinese medicine because of its perceived ability to promote immune function in the elderly. Eight-month-old male SAM-P8 mice were treated with ECD by daily oral administrations for 4 weeks. The results showed that dietary supplementation of 150?mg/kg and 450?mg/kg of ECD could extend the life span measured by Kaplan-Meier survival analysis in dose-dependent manner. Dietary supplementation of SAM-P8 mice for 4 weeks with 100, 500, and 2500?mg/kg of ECD was shown to result in significant increases in both naive T and natural killer cells in blood and spleen cell populations. In contrast, peripheral memory T cells and proinflammatory cytokine, IL-6 in serum, were substantially decreased in the mice that ingested 100 and 500?mg/kg of ECD daily. Additionally, Sca-1 positive cells, the recognized progenitors of peripheral naive T cells, were restored in parallel. Our results provide clear experimental support for long standing clinical observational studies showing that Cistanche deserticola possesses significant effects in extending life span and suggest this is achieved by antagonizing immunosenescence. PMID:24523825

Zhang, Ke; Ma, Xu; He, Wenjun; Li, Haixia; Han, Shuyan; Jiang, Yong; Wu, Hounan; Han, Li; Uotsu, Nobuo; Yamaguchi, Kohji; Ma, Zhizhong; Tu, Pengfei

2014-01-01

291

Genetic modifiers of the Drosophila blue cheese gene link defects in lysosomal transport with decreased life span and altered ubiquitinated-protein profiles.  

PubMed

Defects in lysosomal trafficking pathways lead to decreased cell viability and are associated with progressive disorders in humans. Previously we have found that loss-of-function (LOF) mutations in the Drosophila gene blue cheese (bchs) lead to reduced adult life span, increased neuronal death, and widespread CNS degeneration that is associated with the formation of ubiquitinated-protein aggregates. To identify potential genes that participate in the bchs functional pathway, we conducted a genetic modifier screen based on alterations of an eye phenotype that arises from high-level overexpression of Bchs. We found that mutations in select autophagic and endocytic trafficking genes, defects in cytoskeletal and motor proteins, as well as mutations in the SUMO and ubiquitin signaling pathways behave as modifiers of the Bchs gain-of-function (GOF) eye phenotype. Individual mutant alleles that produced viable adults were further examined for bchs-like phenotypes. Mutations in several lysosomal trafficking genes resulted in significantly decreased adult life spans and several mutants showed changes in ubiquitinated protein profiles as young adults. This work represents a novel approach to examine the role that lysosomal transport and function have on adult viability. The genes characterized in this study have direct human homologs, suggesting that similar defects in lysosomal transport may play a role in human health and age-related processes. PMID:17435236

Simonsen, Anne; Cumming, Robert C; Lindmo, Karine; Galaviz, Vanessa; Cheng, Susan; Rusten, Tor Erik; Finley, Kim D

2007-06-01

292

Dmp53, basket and drICE gene knockdown and polyphenol gallic acid increase life span and locomotor activity in a Drosophila Parkinson's disease model.  

PubMed

Understanding the mechanism(s) by which dopaminergic (DAergic) neurons are eroded in Parkinson's disease (PD) is critical for effective therapeutic strategies. By using the binary tyrosine hydroxylase (TH)-Gal4/UAS-X RNAi Drosophila melanogaster system, we report that Dmp53, basket and drICE gene knockdown in dopaminergic neurons prolong life span (p < 0.05; log-rank test) and locomotor activity (p < 0.05; ?(2) test) in D. melanogaster lines chronically exposed to (1 mM) paraquat (PQ, oxidative stress (OS) generator) compared to untreated transgenic fly lines. Likewise, knockdown flies displayed higher climbing performance than control flies. Amazingly, gallic acid (GA) significantly protected DAergic neurons, ameliorated life span, and climbing abilities in knockdown fly lines treated with PQ compared to flies treated with PQ only. Therefore, silencing specific gene(s) involved in neuronal death might constitute an excellent tool to study the response of DAergic neurons to OS stimuli. We propose that a therapy with antioxidants and selectively "switching off" death genes in DAergic neurons could provide a means for pre-clinical PD individuals to significantly ameliorate their disease condition. PMID:24385865

Ortega-Arellano, Hector Flavio; Jimenez-Del-Rio, Marlene; Velez-Pardo, Carlos

2013-12-01

293

Copyright 2000 by the Genetics Society of America Quantitative Trait Loci for Life Span in Drosophila melanogaster  

E-print Network

of recombinant inbred lines, each of which had been crossed to both inbred parental strains from which the lines mapped within each sex and larval density treatment by linkage to highly polymorphic roo-transposable element markers, using a composite interval mapping method. We detected a total of six QTL affecting life

Mackay, Trudy F.C.

294

Reproductive health and quality of life of young Burmese refugees in Thailand  

PubMed Central

Background Of the 140 000 Burmese* refugees living in camps in Thailand, 30% are youths aged 15-24. Health services in these camps do not specifically target young people and their problems and needs are poorly understood. This study aimed to assess their reproductive health issues and quality of life, and identifies appropriate service needs. Methods We used a stratified two-stage random sample questionnaire survey of 397 young people 15-24 years from 5,183 households, and 19 semi-structured qualitative interviews to assess and explore health and quality of life issues. Results The young people in the camps had very limited knowledge of reproductive health issues; only about one in five correctly answered at least one question on reproductive health. They were clear that they wanted more reproductive health education and services, to be provided by health workers rather than parents or teachers who were not able to give them the information they needed. Marital status was associated with sexual health knowledge; having relevant knowledge of reproductive health was up to six times higher in married compared to unmarried youth, after adjusting for socio-economic and demographic factors. Although condom use was considered important, in practice a large proportion of respondents felt too embarrassed to use them. There was a contradiction between moral views and actual behaviour; more than half believed they should remain virgins until marriage, while over half of the youth experienced sex before marriage. Two thirds of women were married before the age of 18, but two third felt they did not marry at the right age. Forced sex was considered acceptable by one in three youth. The youth considered their quality of life to be poor and limited due to confinement in the camps, the limited work opportunities, the aid dependency, the unclear future and the boredom and unhappiness they face. Conclusions The long conflict in Myanmar and the resultant long stay in refugee camps over decades affect the wellbeing of these young people. Lack of sexual health education and relevant services, and their concerns for their future are particular problems, which need to be addressed. Issues of education, vocational training and job possibilities also need to be considered. *Burmese is used for all ethnic groups PMID:20338037

2010-01-01

295

Life span extensions associated with upregulation of gene expression of antioxidant enzymes in Caenorhabdms elegans; studies of mutation in the AGE-1, PI3 kinase homologue and short-term exposure to hyperoxia.  

PubMed

Life span could be modified by genetic or environmental perturbations in Caenorhabditis elegans. Here we show that two extensions of life span are associated with oxidative stress resistance and upregulation of the gene expression of antioxidant enzymes. First, mutations in age-1 gene (PI3 kinase homologue) that confer life span extension, display oxidative stress resistance and increase in the gene expression of sod-3, one of two Mn-superoxide dismutases (SOD) and ctl-1, cytosolic catalase. In this study, these traits appear to be regulated by the following genetic pathway: daf-2 (insulin receptor family)-> daf-18 (PTEN homologue)-> age-1-> daf-16 (Fork head transcription factor family), similar to the genetic pathway for the life span extension. Second, we show that short-term exposure to hyperoxia extends life span slightly but significantly. This treatment increases oxidative stress resistance and the gene expression of three types of SOD isoforms. These results suggest that both of these two life span extensions are closely related with increase in the antioxidant defense function. PMID:23604883

Honda, Y; Honda, S

2001-10-01

296

Life span extensions associated with upregulation of gene expression of antioxidant enzymes in Caenorhabditis elegans; studies of mutation in the age-1, PI3 kinase homologue and short-term exposure to hyperoxia.  

PubMed

Life span could be modified by genetic or environmental perturbations in Caenorhabditis elegans. Here we show that two extensions of life span are associated with oxidative stress resistance and upregulation of the gene expression of antioxidant enzymes. First, mutations in age-1 gene (PI3 kinase homologue)that confer life span extension, display oxidative stress resistance and increase in the gene expression of sod-3, one of two Mn-superoxide dismutases (SOD) and ctl-1, cytosolic catalase. In this study, these traits appear to be regulated by the following genetic pathway: daf-2 (insulin receptor family)-> daf-18 (PTEN homologue)-> age-1-> daf-16 (Fork head transcription factor family), similar to the genetic pathway for the life span extension. Second, we show that short-term exposure to hyperoxia extends life span slightly but significantly. This treatment increases oxidative stress resistance and the gene expression of three types of SOD isoforms. These results suggest that both of these two life span extensions are closely related with increase in the antioxidant defense function. PMID:23604887

Honda, Y; Honda, S

2002-01-01

297

Outcome of Assisted Reproductive Technology (ART) and Subsequent Self-Reported Life Satisfaction  

PubMed Central

Objective To compare life satisfaction between women with successful or unsuccessful outcome after assisted reproductive treatment (ART) by taking into account the time since the last ART. Design Cohort study. Setting Tertiary hospital. Patients A total of 987 consecutive women who had undergone ART during 19962007 were invited and altogether 505 women participated in the study. Interventions A postal enquiry with a life satisfaction scale. Main Outcome Measure Self-reported life satisfaction in respect to the time since the last ART. Results In general, women who achieved a live birth after ART had a significantly higher life satisfaction than those who had unsuccessful ART, especially when compared in the first three years. The difference disappeared in the time period of 69 years after ART. The unsuccessfully treated women who had a child by some other means before or after the unsuccessful ART had comparable life satisfaction with successfully treated women even earlier. Conclusions Even if unsuccessful ART outcome is associated with subsequent lower level of life satisfaction, it does not seem to threaten the long-term wellbeing. PMID:25393846

Kuivasaari-Pirinen, Paula; Koivumaa-Honkanen, Heli; Hippelinen, Maritta; Raatikainen, Kaisa; Heinonen, Seppo

2014-01-01

298

[Life-span of rats as affected by a combination of external (137Cs) and internal (237Np) radiation].  

PubMed

A study was made of a change in the mean life of rats exposed to external gamma-radiation (51.6 mC/kg) and 237Np (a polymeric nitrate form) administered intratracheally (0.2-188.0 kBq/kg) delivered separately and in a combination. It was established that the effects of gamma- and alpha-radiation were summated. PMID:6739742

Buldakov, L A; Karpova, V N

1984-01-01

299

Reproduction and Early Life History of Ruffe ( Gymnocephalus cernuus) in the St. Louis River, a Lake Superior Tributary  

Microsoft Academic Search

Reproduction and early life history of ruffe (Gymnocephalus ceriums) was investigated during April to July in 1993 and 1994 in the St. Louis River, a western Lake Superior tributary. This study was conducted to assist fishery managers in determining possible interactions among the early life stages of ruffe and other North American percids, and in obtaining information useful in developing

William P. Brown; James H. Selgeby; Hollie L. Collins

1998-01-01

300

Personality, Self-Rated Health and Subjective Age in a Life-Span Sample: The Moderating Role of Chronological Age  

PubMed Central

The present study tested whether chronological age moderates the association between subjective age and self-rated health and personality in a community-dwelling lifespan sample (N=1,016; age-range: 1891). Self-rated health, extraversion, and openness to experience were associated with a younger subjective age at older ages. Conscientious individuals felt more mature early in life. Conscientiousness, neuroticism, and agreeableness were not related to subjective age at older ages. These findings suggest that with aging self-rated health and personality traits are increasingly important for subjective age. PMID:22582885

Stephan, Yannick; Demulier, Virginie; Terracciano, Antonio

2012-01-01

301

The Study of Life Review. An Approach to the Investigation of Intellectual Development across the Life Span. Studien und Berichte 47.  

ERIC Educational Resources Information Center

A study looked for age differences in the quality of responses to the Life Review Task (LRT), studied the LRT itself as a tool for exploring wisdom and intellectual functioning in adulthood, and considered personality characteristics and life experience as alternative predictors of response quality. Sixty-three West German women of different ages

Staudinger, Ursula M.

302

Elevational Variation in Reproductive and Life History Traits of Sauter's Frog Rana sauteri Boulenger, 1909 in Taiwan  

Microsoft Academic Search

Su-Ju Lai, Yeong-Choy Kam and Yao-Sung Lin (2003) Elevational variation in reproductive and life history traits of Sauter's frog Rana sauteri Boulenger, 1909 in Taiwan. Zoological Studies 42(1): 193-202. Sauter's frog, Rana sauteri Boulenger, 1909 in the west-central part of the Central Mountain Range of Taiwan at eleva- tions of 300 to 2360 m showed obvious elevational clines in reproductive

Su-Ju Lai; Yeong-Choy Kam; Yao-Sung Lin

2003-01-01

303

Biodemography of a long-lived tephritid: Reproduction and longevity in a large cohort of female Mexican fruit flies, Anastrepha ludens  

E-print Network

U N C O R R EC TED PR O O F Biodemography of a long-lived tephritid: Reproduction and longevity reproductive rates, and life span were recorded in a laboratory cohort of Mexican fruit flies consisting of egg laying at early ages and both subsequent reproduction and remaining longevity. Discussion includes

Sentürk, Damla

304

Character strengths and well-being across the life span: data from a representative sample of German-speaking adults living in Switzerland  

PubMed Central

Character strengths are positive, morally valued traits of personality. This study aims at assessing the relationship between character strengths and subjective well-being (i.e., life satisfaction, positive and negative affect) in a representative sample of German-speaking adults living in Switzerland (N = 945). We further test whether this relationship is consistent at different stages in life. Results showed that hope, zest, love, social intelligence and perseverance yielded the highest positive correlations with life satisfaction. Hope, zest, humor, gratitude and love presented the highest positive correlations with positive affect. Hope, humor, zest, honesty, and open-mindedness had the highest negative correlations with negative affect. When examining the relationship between strengths and well-being across age groups, in general, hope, zest and humor consistently yielded the highest correlations with well-being. Additionally, in the 2736 years group, strengths that promote commitment and affiliation (i.e., kindness and honesty) were among the first five positions in the ranking of the relationship between strengths and well-being. In the 3746 years group, in addition to hope, zest and humor, strengths that promote the maintenance of areas such as family and work (i.e., love, leadership) were among the first five positions in the ranking. Finally, in the 4757 years group, in addition to hope, zest and humor, strengths that facilitate integration and a vital involvement with the environment (i.e., gratitude, love of learning) were among the first five positions in the ranking. This study partially supports previous findings with less representative samples on the association between character strengths and well-being, and sheds light on the relative importance of some strengths over others for well-being across the life span. PMID:25408678

Martnez-Mart, Mara L.; Ruch, Willibald

2014-01-01

305

Immortalization of Human Fetal Cells: The Life Span of Umbilical Cord Blood-derived Cells Can Be Prolonged without Manipulating p16INK4a/RB Braking PathwayD?  

PubMed Central

Human umbilical cord blood-derived mesenchymal stem cells (UCBMSCs) are expected to serve as an excellent alternative to bone marrow-derived human mesenchymal stem cells. However, it is difficult to study them because of their limited life span. To overcome this problem, we attempted to produce a strain of UCBMSCs with a long life span and to investigate whether the strain could maintain phenotypes in vitro. UCBMSCs were infected with retrovirus carrying the human telomerase reverse transcriptase (hTERT) to prolong their life span. The UCBMSCs underwent 30 population doublings (PDs) and stopped dividing at PD 37. The UCBMSCs newly established with hTERT (UCBTERTs) proliferated for >120 PDs. The p16INK4a/RB braking pathway leading to senescence can be inhibited by introduction of Bmi-1, a polycomb-group gene, and human papillomavirus type 16 E7, but the extension of the life span of the UCBMSCs with hTERT did not require inhibition of the p16INK4a/RB pathway. The characteristics of the UCBTERTs remained unchanged during the prolongation of life span. UCBTERTs provide a powerful model for further study of cellular senescence and for future application to cell-based therapy by using umbilical cord blood cells. PMID:15647378

Terai, Masanori; Uyama, Taro; Sugiki, Tadashi; Li, Xiao-Kang; Umezawa, Akihiro; Kiyono, Tohru

2005-01-01

306

Deletion of the cardiolipin-specific phospholipase Cld1 rescues growth and life span defects in the tafazzin mutant: implications for Barth syndrome.  

PubMed

Cardiolipin (CL) that is synthesized de novo is deacylated to monolysocardiolipin (MLCL), which is reacylated by tafazzin. Remodeled CL contains mostly unsaturated fatty acids. In eukaryotes, loss of tafazzin leads to growth and respiration defects, and in humans, this results in the life-threatening disorder Barth syndrome. Tafazzin deficiency causes a decrease in the CL/MLCL ratio and decreased unsaturated CL species. Which of these biochemical outcomes contributes to the physiological defects is not known. Yeast cells have a single CL-specific phospholipase, Cld1, that can be exploited to distinguish between these outcomes. The cld1? mutant has decreased unsaturated CL, but the CL/MLCL ratio is similar to that of wild type cells. We show that cld1? rescues growth, life span, and respiratory defects of the taz1? mutant. This suggests that defective growth and respiration in tafazzin-deficient cells are caused by the decreased CL/MLCL ratio and not by a deficiency in unsaturated CL. CLD1 expression is increased during respiratory growth and regulated by the heme activator protein transcriptional activation complex. Overexpression of CLD1 leads to decreased mitochondrial respiration and growth and instability of mitochondrial DNA. However, ATP concentrations are maintained by increasing glycolysis. We conclude that transcriptional regulation of Cld1-mediated deacylation of CL influences energy metabolism by modulating the relative contribution of glycolysis and respiration. PMID:24318983

Ye, Cunqi; Lou, Wenjia; Li, Yiran; Chatzispyrou, Iliana A; Httemann, Maik; Lee, Icksoo; Houtkooper, Riekelt H; Vaz, Frdric M; Chen, Shuliang; Greenberg, Miriam L

2014-02-01

307

Increased production of mitochondrial reactive oxygen species and reduced adult life span in an insecticide-resistant strain of Anopheles gambiae.  

PubMed

Control of the malaria vector An. gambiae is still largely obtained through chemical intervention using pyrethroids, such as permethrin. However, strains of An. gambiae that are resistant to the toxic effects of pyrethroids have become widespread in several endemic areas over the last decade. The objective of this study was to assess differences in five life-history traits (larval developmental time and the body weight, fecundity, hatch rate, and longevity of adult females) and energy metabolism between a strain of An. gambiae that is resistant to permethrin (RSP), due to knockdown resistance and enhanced metabolic detoxification, and a permethrin susceptible strain reared under laboratory conditions. We also quantified the expression levels of five antioxidant enzyme genes: GSTe3, CAT, GPXH1, SOD1, and SOD2. We found that the RSP strain had a longer developmental time than the susceptible strain. Additionally, RSP adult females had higher wet body weight and increased water and glycogen levels. Compared to permethrin susceptible females, RSP females displayed reduced metabolic rate and mitochondrial coupling efficiency and higher mitochondrial ROS production. Furthermore, despite higher levels of GSTe3 and CAT transcripts, RSP females had a shorter adult life span than susceptible females. Collectively, these results suggest that permethrin resistance alleles might affect energy metabolism, oxidative stress, and adult survival of An. gambiae. However, because the strains used in this study differ in their genetic backgrounds, the results need to be interpreted with caution and replicated in other strains to have significant implications for malaria transmission and vector control. PMID:24555527

Otali, D; Novak, R J; Wan, W; Bu, S; Moellering, D R; De Luca, M

2014-06-01

308

Cardiovascular determinants of life span  

Microsoft Academic Search

The prevalence of cardiovascular diseases rises with aging and is one of the main causes of mortality in western countries.\\u000a In view of the progressively aging population, there is an urge for a better understanding of age-associated cardiovascular\\u000a diseases and its underlying molecular mechanisms. The risk factors for cardiovascular diseases include unhealthy diet, diabetes,\\u000a obesity, smoking, alcohol consumption, physical inactivity,

Yi Shi; Giovanni G. Camici; Thomas F. Lscher

2010-01-01

309

Male alternative reproductive behaviours in a Mediterranean wrasse, Symphodus ocellatus: Evidence from otoliths for multiple life-history pathways  

Microsoft Academic Search

Although alternative reproductive behaviours have been studied extensively, it has only been possible in a few cases to document the underlying life-history pathways and factors that determine their expression. In Symphodus ocellatus, a Mediterranean wrasse, males adopt a variety of behaviours. Within a season, they may invest in territory defence, nest building and broodcare (nesting males); join nesting males in

Suzanne H. Alonzo; Michael Taborsky; Peter Wirtz

310

LIFE HISTORY AND REPRODUCTIVE BIOLOGY OF THE GILGIE, CHERAX QUINQUECARINATUS, A FRESHWATER CRAYFISH ENDEMIC TO SOUTHWESTERN AUSTRALIA  

Microsoft Academic Search

The gilgie, Cherax quinquecarinatus, a freshwater crayfish endemic to southwestern Western Australia, occupies a wide range of permanent and temporary aquatic environments. Reproductive and population biology parameters were determined in Bull Creek, southwestern Western Australia. Crayfish were collected monthly from May 2002 to April 2003. The seasonal von Bertalanffy growth curve, fitted for the first 14 months of life for

Stephen J. Beatty; David L. Morgan; Howard S. Gill

2005-01-01

311

Stereotypes of Women in Different Stages of Their Reproductive Life: Data From Mexico and the United States  

Microsoft Academic Search

College students from Mexico and the United States (n = 349) were surveyed to explore stereotypes regarding women in different menstrual cycle phases and other stages of reproductive life. Participants from both countries defined a premenstrual or menstrual woman as irritable and moody and a menopausal woman as old and irritable. A woman with a hysterectomy was defined as sad,

Ma. Luisa Marvn; Martha Islas; Laura Vela; Joan C. Chrisler; Elyse A. Warren

2008-01-01

312

Rho Kinase Inhibitor Y-27632 Prolongs the Life Span of Adult Human Keratinocytes, Enhances Skin Equivalent Development, and Facilitates Lentiviral Transduction  

PubMed Central

The use of tissue-engineered human skin equivalents (HSE) for fundamental research and industrial application requires the expansion of keratinocytes from a limited number of skin biopsies donated by adult healthy volunteers or patients. A pharmacological inhibitor of Rho-associated protein kinases, Y-27632, was recently reported to immortalize neonatal human foreskin keratinocytes. Here, we investigated the potential use of Y-27632 to expand human adult keratinocytes and evaluated its effects on HSE development and in vitro gene delivery assays. Y-27632 was found to significantly increase the life span of human adult keratinocytes (up to five to eight passages). The epidermal morphology of HSEs generated from high-passage, Y-27632-treated keratinocytes resembled the native epidermis and was improved by supplementing Y-27632 during the submerged phase of HSE development. In addition, Y-27632-treated keratinocytes responded normally to inflammatory stimuli, and could be used to generate HSEs with a psoriatic phenotype, upon stimulation with relevant cytokines. Furthermore, Y-27632 significantly enhanced both lentiviral transduction efficiency of primary adult keratinocytes and epidermal morphology of HSEs generated thereof. Our study indicates that Y-27632 is a potentially powerful tool that is used for a variety of applications of adult human keratinocytes. PMID:22519508

Rodijk-Olthuis, Diana; Jansen, Patrick A.M.; van Vlijmen-Willems, Ivonne M.J.J.; van Erp, Piet E.; Joosten, Irma; Zeeuwen, Patrick L.J.M.

2012-01-01

313

Tackling Vision-Related Disability in Old Age: An Application of the Life-Span Theory of Control to Narrative Data  

PubMed Central

This study used the life-span theory of control (Heckhausen, J., & Schulz, R.) to examine adaptation to disability in old age. A narrative approach to data collection was used to assess the strategies employed by 364 older adults with macular degeneration to deal with daily challenges. Findings revealed a rich array of strategies. Compensatory Primary Control was reported by nearly all respondents, Compensatory Secondary Control by a majority, and Selective Primary Control by half of the participants. Selective Secondary Control was the least reported. Differences in strategy use depending on level of vision impairment were the most pronounced within the category of Compensatory Primary Control for strategies that involved using help from others and alternative means. Within the category of Selective Secondary Control, effort to maintain a positive outlook was associated with higher impairment levels, whereas within the category of Compensatory Secondary Control, attempts not to dwell on problems related to vision were associated with lower impairment levels. Implications for conceptual development and future research are discussed. PMID:19965902

Brennan, Mark; Horowitz, Amy; Reinhardt, Joann P.

2010-01-01

314

Assessing the burden of sexual and reproductive ill-health: questions regarding the use of disability-adjusted life years.  

PubMed Central

The use of the disability-adjusted life year (DALY) as the unit in which to calculate the burden of disease associated with reproductive ill-health has given rise to considerable debate. Criticisms include the failure to address the problem of missing and inadequate epidemiological data, inability to deal adequately with co-morbidities, and lack of transparency in the process of ascribing disability weights to sexual and reproductive health conditions. Many of these criticisms could be addressed within the current DALY framework and a number of suggestions to do so are made. These suggestions include: (1) developing an international research strategy to determine the incidence and prevalence of reproductive ill-health and diseases, including the risk of long-term complications; (2) undertaking a research strategy using case studies, population-based surveillance data and longitudinal studies to identify, evaluate and utilize more of the existing national data sources on sexual and reproductive health; (3) comprehensively mapping the natural history of sexual and reproductive health conditions--in males and in females--and their sequelae, whether physical or psychological; (4) developing valuation instruments that are adaptable for both chronic and acute health states, that reflect a range of severity for each health state and can be modified to reflect prognosis; (5) undertaking a full review of the DALY methodology to determine what changes may be made to reduce sources of methodological and gender bias. Despite the many criticisms of the DALY as a measurement unit, it represents a major conceptual advance since it permits the combination of life expectancy and levels of dysfunction into a single measure. Measuring reproductive ill-health by counting deaths alone is inadequate for a proper understanding of the dimensions of the problem because of the young age of many of the deaths associated with reproductive ill-health and the large component of years lived with disability from many of the associated conditions. PMID:10859859

AbouZahr, C.; Vaughan, J. P.

2000-01-01

315

Life-cycle exposure to the estrogenic mycotoxin zearalenone affects zebrafish (Danio rerio) development and reproduction.  

PubMed

Zearalenone (ZON) is one of the worldwide most common mycotoxin and exhibits estrogenic activity in the range of natural steroid estrogens. The occurrence of ZON has been reported in soil, drainage water, wastewater effluents, and rivers, but its ecotoxicological effects on fish have hardly been investigated. The consequences of continuous long-term ZON exposure, including a subsequent depuration period, as well as transgenerational effects of F0 short-term exposure on F1 generation were investigated. Effects on growth, reproduction activity, physiology, and morphology of zebrafish (Danio rerio) were examined in a 182 day live-cycle experiment. Life-long exposure to ZON for 140 days increased wet weight, body length, and condition factor of female fish at 1000 ng/L, and sex ratio was shifted toward female from 320 ng/L ZON. Only females at 1000 ng/L ZON revealed a 1.5-fold induction of plasma vitellogenin (VTG). Relative fecundity at 1000 ng/L recovered significantly during the depuration period. An increased condition factor in adult female F1 fish implies that exposure of F0 generation to 1000 ng/L ZON affected growth of F1 generation. A negative correlation between relative fecundity in the F1 generation (all groups exposed to 320 ng/L ZON) and the nominal ZON concentrations of the F0 exposure might indicate an influence of F0 exposure on reproductive performance of F1 generation. No exposure scenario affected fertility, hatch, embryo survival, and gonad morphology of zebrafish. Evaluating the environmental relevance of this data, the risk for fish to be harmed by exposure to ZON solely seems rather marginal, but ZON might contribute to the overall estrogenicity in the environment. 2011 Wiley Periodicals, Inc. Environ Toxicol 2013. PMID:21695757

Schwartz, Patrick; Bucheli, Thomas D; Wettstein, Felix E; Burkhardt-Holm, Patricia

2013-05-01

316

Reproductive Effort and Reproductive Values in Periodic Environments.  

PubMed

Life-history theory concerns the optimal spread of reproduction over an organism's life span. In variable environments, there may be extrinsic differences between breeding periods within an organism's life, affecting both offspring and parent and giving rise to intergenerational trade-offs. Such trade-offs are often discussed in terms of reproductive value for parent and offspring. Here, we consider parental life-history optimization in response to varying offspring values of a population regulated by territoriality, where the quality of the environment varies periodically. Periods are interpreted as either within-year (seasonality) or between-years variation (cyclicity). The evolutionarily stable strategy in a general model with two-phased periodicity in the environment can generate either higher or lower effort in the more favorable of the two phases; hence knowing survival prospects of offspring does not suffice for predicting reproductive effort-the future of all descendants and the parent must be tracked. We also apply our method to data on the Ural owl Strix uralensis, a species preying on cyclically fluctuating voles. The observed dynamics are best predicted by assuming delayed reproductive costs and Type II functional response. Accounting for varying offspring values can lead to cases where both reproductive effort and recruitment of offspring are higher in the phase when voles are not maximally abundant, a pattern supported by our data. PMID:10753074

Brommer; Kokko; Pietiinen

2000-04-01

317

Relating Life-Span Research to the Development of Gifted and Talented Children. Abstracts of Selected Papers [from] The Annual Esther Katz Rosen Symposium on the Psychological Development of Gifted Children (3rd, Lawrence, Kansas, February 19-20, 1993).  

ERIC Educational Resources Information Center

This monograph presents abstracts of 29 papers that relate life-span research to the development of gifted and talented children. Sample topics include: attitudes about rural schools and programs for the gifted; social competence, self-esteem, and parent-child time and interaction in an advantaged subculture; helping families of gifted children

Kansas Univ., Lawrence.

318

Combination of hTERT and bmi-1, E6, or E7 Induces Prolongation of the Life Span of Bone Marrow Stromal Cells from an Elderly Donor without Affecting Their Neurogenic Potential  

PubMed Central

Murine bone marrow stromal cells differentiate not only into mesodermal derivatives, such as osteocytes, chondrocytes, adipocytes, skeletal myocytes, and cardiomyocytes, but also into neuroectodermal cells in vitro. Human bone marrow stromal cells are easy to isolate but difficult to study because of their limited life span. To overcome this problem, we attempted to prolong the life span of bone marrow stromal cells and investigated whether bone marrow stromal cells modified with bmi-1, hTERT, E6, and E7 retained their differentiated capability, or multipotency. In this study, we demonstrated that the life span of bone marrow stromal cells derived from a 91-year-old donor could be extended and that the stromal cells with an extended life span differentiated into neuronal cells in vitro. We examined the neuronally differentiated cells morphologically, physiologically, and biologically and compared the gene profiles of undifferentiated and differentiated cells. The neuronally differentiated cells exhibited characteristics similar to those of midbrain neuronal progenitors. Thus, the results of this study support the possible use of autologous-cell graft systems to treat central nervous system diseases in geriatric patients. PMID:15923633

Mori, Taisuke; Kiyono, Tohru; Imabayashi, Hideaki; Takeda, Yukiji; Tsuchiya, Kohei; Miyoshi, Shunichirou; Makino, Hatsune; Matsumoto, Kenji; Saito, Hirohisa; Ogawa, Satoshi; Sakamoto, Michiie; Hata, Jun-Ichi; Umezawa, Akihiro

2005-01-01

319

Disability-Adjusted Life Years for Breast and Reproductive System Cancers in Cuban Women of Child bearing Age.  

PubMed

INTRODUCTION Disability-adjusted life years is a composite measure that integrates the components of mortality and morbidity. It is a useful indicator of overall disease burden and is particularly useful for evaluating health intervention outcomes. In the cases of breast and reproductive system cancers, these can also negatively affect childbearing opportunities for young women. OBJECTIVE Determine disability-adjusted life years for breast and reproductive system cancers in Cuban women aged 15-44 years during the period 1990-2006. METHODS A national epidemiological study was conducted using Cuba's disease and vital statistics registry data for 1990, 1995, 2000 and 2006. Disability-adjusted life years in women aged 15-44 years were calculated for breast cancer and three female reproductive system cancers (cervical, endometrial and ovarian), by summing years of life lost due to premature mortality and years lived with disability. Years of life lost due to premature mortality were determined based on age-specific estimates of life expectancy. Years lived with disability were calculated as the product of severities (provided by the 1990 Global Burden of Disease study) and incidence and average duration, both obtained via the DISMOD II program. Data entered in the program include national statistics on incidence, prevalence, and mortality. RESULTS Breast cancer and cervical cancer proved to have the highest rates of potential years of life lost due to premature mortality, with the sharpest increases in the period (from 139 to 206.5 and 114.7 to 215.2 per 100,000, respectively). Endometrial and ovarian neoplasms crept up more slowly. An increase in years lived with disability was seen in three of these four types of cancer; only cervical cancer saw a decline (from 12.7 to 9 per 100,000). Breast cancer and cervical cancer presented the highest levels of disability-adjusted life years for all four years studied, rising from 146.9 to 227.8 and 127.4 to 224.2 per 100,000, respectively between 1990 and 2006. CONCLUSIONS An unfavorable trend in disability-adjusted life years was seen for breast and cervical cancer between 1990 and 2006 in Cuban women of childbearing age. KEYWORDS Disability-adjusted life years, years of life lost due to premature mortality, years lived with disability, cancer, breast, female reproductive system, fertility, Cuba. PMID:25208113

Domnguez, Emma; Santana, Felipe; Seuc, Armando H

2014-01-01

320

A Widespread Chromosomal Inversion Polymorphism Contributes to a Major Life-History Transition, Local Adaptation, and Reproductive Isolation  

PubMed Central

The role of chromosomal inversions in adaptation and speciation is controversial. Historically, inversions were thought to contribute to these processes either by directly causing hybrid sterility or by facilitating the maintenance of co-adapted gene complexes. Because inversions suppress recombination when heterozygous, a recently proposed local adaptation mechanism predicts that they will spread if they capture alleles at multiple loci involved in divergent adaptation to contrasting environments. Many empirical studies have found inversion polymorphisms linked to putatively adaptive phenotypes or distributed along environmental clines. However, direct involvement of an inversion in local adaptation and consequent ecological reproductive isolation has not to our knowledge been demonstrated in nature. In this study, we discovered that a chromosomal inversion polymorphism is geographically widespread, and we test the extent to which it contributes to adaptation and reproductive isolation under natural field conditions. Replicated crosses between the prezygotically reproductively isolated annual and perennial ecotypes of the yellow monkeyflower, Mimulus guttatus, revealed that alternative chromosomal inversion arrangements are associated with life-history divergence over thousands of kilometers across North America. The inversion polymorphism affected adaptive flowering time divergence and other morphological traits in all replicated crosses between four pairs of annual and perennial populations. To determine if the inversion contributes to adaptation and reproductive isolation in natural populations, we conducted a novel reciprocal transplant experiment involving outbred lines, where alternative arrangements of the inversion were reciprocally introgressed into the genetic backgrounds of each ecotype. Our results demonstrate for the first time in nature the contribution of an inversion to adaptation, an annual/perennial life-history shift, and multiple reproductive isolating barriers. These results are consistent with the local adaptation mechanism being responsible for the distribution of the two inversion arrangements across the geographic range of M. guttatus and that locally adaptive inversion effects contribute directly to reproductive isolation. Such a mechanism may be partially responsible for the observation that closely related species often differ by multiple chromosomal rearrangements. PMID:20927411

Lowry, David B.; Willis, John H.

2010-01-01

321

Measurement invariance of big-five factors over the life span: ESEM tests of gender, age, plasticity, maturity, and la dolce vita effects.  

PubMed

This substantive-methodological synergy applies evolving approaches to factor analysis to substantively important developmental issues of how five-factor-approach (FFA) personality measures vary with gender, age, and their interaction. Confirmatory factor analyses (CFAs) conducted at the item level often do not support a priori FFA structures, due in part to the overly restrictive assumptions of CFA models. Here we demonstrate that exploratory structural equation modeling (ESEM), an integration of CFA and exploratory factor analysis, overcomes these problems with the 15-item Big Five Inventory administered as part of the nationally representative British Household Panel Study (N = 14,021; age: 15-99 years, Mage = 47.1). ESEM fitted the data substantially better and resulted in much more differentiated (less correlated) factors than did CFA. Methodologically, we extended ESEM (introducing ESEM-within-CFA models and a hybrid of multiple groups and multiple indicators multiple causes models), evaluating full measurement invariance and latent mean differences over age, gender, and their interaction. Substantively the results showed that women had higher latent scores for all Big Five factors except for Openness and that these gender differences were consistent over the entire life span. Substantial nonlinear age effects led to the rejection of the plaster hypothesis and the maturity principle but did support a newly proposed la dolce vita effect in old age. In later years, individuals become happier (more agreeable and less neurotic), more self-content and self-centered (less extroverted and open), more laid back and satisfied with what they have (less conscientious, open, outgoing and extroverted), and less preoccupied with productivity. PMID:22250996

Marsh, Herbert W; Nagengast, Benjamin; Morin, Alexandre J S

2013-06-01

322

Correlations of life-span variation parameters in 128 successive generations of Drosophila melanogaster with changes in atmospheric pressure and geomagnetic activity  

NASA Astrophysics Data System (ADS)

Correlations between the parameters of life-span (LS) distribution of Drosophila melanogaster, including mean LS (MLS) and the time of 10 and 90% population mortality, and some geophysical parameters that are usually beyond the control of researchers dealing with laboratory cultures, including atmospheric pressure, solar activity indices (Wolfs sunspot numbers and 2,800-MHz radio flux), and geomagnetic activity (planetary index, Kp), were studied. Geophysical data were obtained from free-access official web sites of the National Oceanic & Atmospheric Administration of the US Department of Commerce and the Institute of Terrestrial Magnetism and Radiowave Propagation of the Russian Academy of Sciences. The geophysical parameters were calculated only for the period corresponding to 10 days of preimaginal development of the flies from egg to imago. Canonical correlation analysis, calculation of the non-parametric Spearman rank-order correlation coefficients, and graphical data analysis were used. Highly significant correlations between parameters of LS distribution in males and females and environmental factors, such as the atmospheric pressure on the 4th and 5th day of development and geomagnetic activity indices (Kp) on the 6th and 10th day of development were found, with correlation coefficients varying from 0.31 to 0.37 (P<0.02). Assuming a causal relationship between geophysical factors and LS, it may be hypothesized that energetically weak environmental factors determine the formation of LS oscillatory dynamics in laboratory populations. The possible mechanisms underlying the contribution of these environmental factors to the LS variation in successive generations are discussed.

Izmaylov, D. M.; Obukhova, L. K.; Konradov, A. A.

2005-05-01

323

Recruitment and Retention Strategies for Minority or Poor Clinical Research Participants: Lessons From the Healthy Aging in Neighborhoods of Diversity Across the Life Span Study  

PubMed Central

Purpose of the study:?Investigating health disparities requires studies designed to recruit and retain racially and socioeconomically diverse cohorts. It is critical to address the barriers that disproportionately affect participation in clinical research by minorities and the socioeconomically disadvantaged. This study sought to identify and rectify these barriers to recruit and retain a biracial (African American and non-Hispanic White) and socioeconomically diverse cohort for a longitudinal study.?Design and Method:?The Healthy Aging in Neighborhoods of Diversity across the Life Span study is a 20-year longitudinal examination of how race and socioeconomic status influence the development of age-related health disparities. One goal was to create a multifactorial recruitment and retention strategy. The recruitment paradigm targeted known barriers and identified those unique to the study's urban environment. The retention paradigm mirrored the recruitment plan but was based on specifically developed approaches.?Results:?This cohort recruitment required attention to developing community partnerships, designing the research study to meet the study hypotheses and to provide benefit to participants, providing a safe community-based site for the research and creating didactics to develop staff cultural proficiency. These efforts facilitated study implementation and enhanced recruitment resulting in accrual of a biracial and socioeconomically diverse cohort of 3,722 participants.?Implications:?Recruiting and retaining minority or poor research participants is challenging but possible. The essential facets include clear communication of the research hypothesis, focus on providing a direct benefit for participants, and selection of a hypothesis that is directly relevant to the community studied PMID:21565817

Ejiogu, Ngozi; Norbeck, Jennifer H.; Mason, Marc A.; Cromwell, Bridget C.; Zonderman, Alan B.; Evans, Michele K.

2011-01-01

324

Marker-assisted determination of the relationship between body size and reproductive success and consequences for evaluation of adaptive life histories.  

PubMed

We tested for differences in the predicted optimal ages at first maturity in brook charr (Salvelinus fontinalis) in Freshwater River, Newfoundland, when life-history data were collated based on the marker-assisted estimation of the relationship between body size and reproductive success rather than using fecundity as a surrogate for reproductive success. Jointly with capture-recapture data to estimate the growth and survival costs of reproduction, we found that weak relationships between body size and reproductive success generate selection against delayed maturation. This finding would not have held for females if the relationship between body size and fecundity had been used as a surrogate for the relationship between body size and reproductive success. This shows that predictions of optimal life histories can be qualitatively changed when using molecular markers to directly evaluate age- and/or size-specific effects of body size on reproductive success. PMID:19765223

Morrissey, Michael B; Ferguson, Moira M

2009-10-01

325

Reproductive adaptation in Drosophila exposed to oxygen-enriched atmospheres  

NASA Technical Reports Server (NTRS)

Ten successive generations of a Drosophila melanogaster population were exposed to an atmospheric mix of 50% oxygen/50% nitrogen at standard pressure. This atmospheric mix has been shown to be toxic to this species and causes significantly shortened life span. By the fifth generation, survivorship and life span for the first 25-30 days were identical to control populations and total life span was shorter by only a few days. Egg-laying rates were stable in the experimental populations but below those of the controls. Hatching success was identical between experimental and control populations. Even though the egg-laying rates were lower in 50% oxygen, it was concluded that the population had adapted and could maintain a stable population in these conditions. The near-normal life spans, normal hatching rates, and overall population stability, exhibited following five generations of adaptation, were considered sufficient to allow continued reproduction in spite of a reduced egg-laying rate.

Kloek, G.; Winkle, L.

1979-01-01

326

Early Life Exposure to Endocrine-Disrupting Chemicals Causes Lifelong Molecular Reprogramming of the Hypothalamus and Premature Reproductive Aging  

PubMed Central

Gestational exposure to the estrogenic endocrine disruptor methoxychlor (MXC) disrupts the female reproductive system at the molecular, physiological, and behavioral levels in adulthood. The current study addressed whether perinatal exposure to endocrine disruptors reprograms expression of a suite of genes expressed in the hypothalamus that control reproductive function and related these molecular changes to premature reproductive aging. Fischer rats were exposed daily for 12 consecutive days to vehicle (dimethylsulfoxide), estradiol benzoate (EB) (1 mg/kg), and MXC (low dose, 20 ?g/kg or high dose, 100 mg/kg), beginning on embryonic d 19 through postnatal d 7. The perinatally exposed females were aged to 1617 months and monitored for reproductive senescence. After euthanasia, hypothalamic regions [preoptic area (POA) and medial basal hypothalamus] were dissected for real-time PCR of gene expression or pyrosequencing to assess DNA methylation of the Esr1 gene. Using a 48-gene PCR platform, two genes (Kiss1 and Esr1) were significantly different in the POA of endocrine-disrupting chemical-exposed rats compared with vehicle-exposed rats after Bonferroni correction. Fifteen POA genes were up-regulated by at least 50% in EB or high-dose MXC compared with vehicle. To understand the epigenetic basis of the increased Esr1 gene expression, we performed bisulfite conversion and pyrosequencing of the Esr1 promoter. EB-treated rats had significantly higher percentage of methylation at three CpG sites in the Esr1 promoter compared with control rats. Together with these molecular effects, perinatal MXC and EB altered estrous cyclicity and advanced reproductive senescence. Thus, early life exposure to endocrine disruptors has lifelong effects on neuroendocrine gene expression and DNA methylation, together with causing the advancement of reproductive senescence. PMID:22016562

Walker, Deena M.; Zama, Aparna M.; Armenti, AnnMarie E.; Uzumcu, Mehmet

2011-01-01

327

INFLUENCE OF THE ORGANOPHOSPHATE INSECTICIDE FENTHION ON 'MYSIDOPSIS BAHIA' EXPOSED DURING A COMPLETE LIFE CYCLE: 1. SURVIVAL, REPRODUCTION, AND AGE-SPECIFIC GROWTH  

EPA Science Inventory

Survival, growth, and various measures of reproductive performance were examined for an estuarine mysid, Mysidopsis bahia, throughout its life cycle during exposure to the organophosphate insecticide, fenthion. Both individual fecundity of females and total population production ...

328

Life history plasticity after attaining a dietary threshold for reproduction is associated with protein storage in flesh flies  

PubMed Central

Summary Body condition affects the timing and magnitude of life history transitions. Therefore, identifying proximate mechanisms involved in assessing condition is critical to understanding how these mechanisms affect the expression of life history plasticity. Nutrient storage is an important body condition parameter, likely playing roles in both attaining minimum body-condition thresholds for life history transitions and expression of life history traits. We manipulated protein availability for females of the flesh fly Sarcophaga crassipalpis to determine whether reproductive timing and output would remain plastic or become fixed. Liver was provided for 0, 2, 4, or 6 days of adult pre-reproductive development. Significantly, liver was removed after the feeding threshold had been attained and females had committed to producing a clutch. We also identified the major storage proteins and monitored their abundances, because protein stores may serve as an index of body condition and therefore may play an important role in life history transitions and plasticity. Flesh flies showed clear post-threshold plasticity in reproductive timing. Females fed protein for 2 days took ~30% longer to provision their clutch than those fed for 4 or 6 days. Observations of oogenesis showed the 2-day group expressed a different developmental program including slower egg provisioning. Protein availability also affected reproductive output. Females fed protein for 2 days produced ~20% fewer eggs than females fed 4 or 6 days. Six-day treated females provisioned larger eggs than 4-day treated females, followed by 2-day treated females with the smallest eggs. Two storage proteins were identified, LSP-1 and LSP-2. LSP-2 accumulation differed across feeding treatments. The 2- and 4-day treatment groups accumulated LSP-2 stores but depleted them during provisioning of the first clutch, whereas the 6-day group accumulated the greatest quantity of LSP-2 and had substantial LSP-2 stores remaining at the end of the clutch. This pattern of accumulation and depletion suggests that LSP-2 could play roles in both provisioning the current clutch and future clutches, making it a good candidate molecule for affecting reproductive timing and allotment. LSP-1 was not associated with post-threshold plasticity; it was carried over from larval feeding into adulthood and depleted uniformly across all feeding groups. PMID:19789714

Hahn, Daniel A.; James, Laura N.; Milne, Kathy R.; Hatle, John D.

2009-01-01

329

Latitudinal variation in life-cycle characteristics of Potamogeton pectinatus L.: vegetative growth and asexual reproduction  

Microsoft Academic Search

Across latitudinal gradients, environmental conditions that influenceplant growth and reproduction largely change. Here we study clonal variation inlife-cycle characteristics of the cosmopolitan water plantPotamogetonpectinatus L. across a broad latitudinal range.Two consecutive experiments were performed under standardised laboratoryconditions (photoperiod, irradiance and temperature). In the first experimentweinvestigated asexual reproduction among fifteen clones, obtained from latitudesranging from 24 to 68 N. After 90

Jrn Pilon; Luis Santamara; Michiel Hootsmans; Wim van Vierssen

2003-01-01

330

Potential Gains in Reproductive-Aged Life Expectancy by Eliminating Maternal Mortality: A Demographic Bonus of Achieving MDG 5  

PubMed Central

Objective We assessed the change over time in the contribution of maternal mortality to a life expectancy calculated between ages 15 and 49, or Reproductive-Aged Life Expectancy (RALE). Our goal was to estimate the increase in RALE in developed countries over the twentieth century and the hypothetical gains in African countries today by eliminating maternal mortality. Methods Analogous to life expectancy, RALE is calculated from a life table of ages 15 to 49. Specifically, RALE is the average number of years that women at age 15 would be expected to live between 15 and 49 with current mortality rates. Associated single decrement life tables of causes of death other than maternal mortality are explored to assess the possible gains in RALE by reducing or eliminating maternal mortality. We used population-based data from the Human Mortality Database and the Demographic and Health Surveys. Findings In developed countries, five years in RALE were gained over the twentieth century, of which approximately 10%, or half a year, was attributable to reductions in maternal mortality. In sub-Saharan African countries, the possible achievable gains fluctuate between 0.24 and 1.47 years, or 6% and 44% of potential gains in RALE. Conclusions Maternal mortality is a rare event, yet it is still a very important component of RALE. Averting the burden of maternal deaths could return a significant increase in the most productive ages of human life. PMID:24551040

Canudas-Romo, Vladimir; Liu, Li; Zimmerman, Linnea; Ahmed, Saifuddin; Tsui, Amy

2014-01-01

331

Life History and the Costs of Reproduction in Northern Great Plains Paddlefish (Polyodon spathula) as a Potential Framework for Other Acipenseriform Fishes  

Microsoft Academic Search

A 14-year investigation of a North American Acipenseriform fish, the paddlefish Polyodon spathula in the Yellowstone River, Montana, and North Dakota, USA has provided a detailed empirical framework of the life history in relation to the costs of reproduction for that species and potentially for closely related sturgeons. Nearly all aspects of life histories of males and females differed from

Dennis L. Scarnecchia; L. Fred Ryckman; Youngtaik Lim; Greg J. Power; Brad J. Schmitz; Jon A. Firehammer

2007-01-01

332

Influence of breastfeeding and other reproductive factors on bone mass later in life  

Microsoft Academic Search

The influence of reproductive factors on bone mass at six skeletal sites was assessed in an age-stratified random sample of white women residing in Rochester, Minnesota. After age-adjustment, whether or not women had ever breastfed, total duration of breastfeeding and duration of breastfeeding per child were not associated with reduced bone mineral, but breastfeeding for more than 8 months was

L. J. Melton; S. C. Bryant; H. W. Wahner; W. M. O'Fallon; G. D. Malkasian; H. L. Judd; B. L. Riggs

1993-01-01

333

Seasonal trends in Ceratitis capitata reproductive potential derived from live-caught females in Greece.  

PubMed

Reproductive data of individual insects are extremely hard to collect under natural conditions, thus the study of research questions related to oviposition has not advanced. Patterns of oviposition are often inferred only indirectly, through monitoring of host infestation, whereas the influence of age structure and several other factors on oviposition remains unknown. Using a new approach, in this article, we live-trapped wild Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) females on the Greek island of Chios during two field seasons. For their remaining lifetime, these females were placed individually in small cages and their daily oviposition was monitored. Reproduction rates between cohorts from different collection dates were then compared. The results showed that in the different captive cohorts the average remaining lifetime and reproduction were highly variable within and between seasons. Multivariate regression analysis showed that the month of capture had a significant effect on captive life span, average daily reproduction, and patterns of egg laying. The effect of year was significant on reproduction, but not on captive life span. These differences between sampling periods probably reflect differences in the availability of hosts and other factors that vary during the season and affect age structure and reproduction. Using a non-parametric generalized additive model, we found a statistically significant correlation between the captive life span and the average daily reproduction. These findings and the experimental approach have several important implications. PMID:22791908

Kouloussis, Nikos A; Papadopoulos, Nikos T; Katsoyannos, Byron I; Mller, Hans-Georg; Wang, Jane-Ling; Su, Yu-Ru; Molleman, Freerk; Carey, James R

2011-09-01

334

Influence of early-life nutrition on mortality and reproductive success during a subsequent famine in a preindustrial population.  

PubMed

Individuals with insufficient nutrition during development often experience poorer later-life health and evolutionary fitness. The Predictive Adaptive Response (PAR) hypothesis proposes that poor early-life nutrition induces physiological changes that maximize fitness in similar environments in adulthood and that metabolic diseases result when individuals experiencing poor nutrition during development subsequently encounter good nutrition in adulthood. However, although cohort studies have shown that famine exposure in utero reduces health in favorable later-life conditions, no study on humans has demonstrated the predicted fitness benefit under low later-life nutrition, leaving the evolutionary origins of such plasticity unexplored. Taking advantage of a well-documented famine and unique datasets of individual life histories and crop yields from two preindustrial Finnish populations, we provide a test of key predictions of the PAR hypothesis. Known individuals from fifty cohorts were followed from birth until the famine, where we analyzed their survival and reproductive success in relation to the crop yields around birth. We were also able to test whether the long-term effects of early-life nutrition differed between individuals of varying socioeconomic status. We found that, contrary to predictions of the PAR hypothesis, individuals experiencing low early-life crop yields showed lower survival and fertility during the famine than individuals experiencing high early-life crop yields. These effects were more pronounced among young individuals and those of low socioeconomic status. Our results do not support the hypothesis that PARs should have been favored by natural selection and suggest that alternative models may need to be invoked to explain the epidemiology of metabolic diseases. PMID:23918366

Hayward, Adam D; Rickard, Ian J; Lummaa, Virpi

2013-08-20

335

SPAN: Astronomy and astrophysics  

NASA Technical Reports Server (NTRS)

The Space Physics Analysis Network (SPAN) is a multi-mission, correlative data comparison network which links science research and data analysis computers in the U.S., Canada, and Europe. The purpose of this document is to provide Astronomy and Astrophysics scientists, currently reachable on SPAN, with basic information and contacts for access to correlative data bases, star catalogs, and other astrophysic facilities accessible over SPAN.

Thomas, Valerie L.; Green, James L.; Warren, Wayne H., Jr.; Lopez-Swafford, Brian

1987-01-01

336

An FXPRLamide Neuropeptide Induces Seasonal Reproductive Polyphenism Underlying a Life-History Tradeoff in the Tussock Moth  

PubMed Central

The white spotted tussock moth, Orgyia thyellina, is a typical insect that exhibits seasonal polyphenisms in morphological, physiological, and behavioral traits, including a life-history tradeoff known as oogenesis-flight syndrome. However, the developmental processes and molecular mechanisms that mediate developmental plasticity, including life-history tradeoff, remain largely unknown. To analyze the molecular mechanisms involved in reproductive polyphenism, including the diapause induction, we first cloned and characterized the diapause hormone-pheromone biosynthesis activating neuropeptide (DH-PBAN) cDNA encoding the five Phe-X-Pro-Arg-Leu-NH2 (FXPRLa) neuropeptides: DH, PBAN, and ?-, ?-, and ?-SGNPs (subesophageal ganglion neuropeptides). This gene is expressed in neurosecretory cells within the subesophageal ganglion whose axonal projections reach the neurohemal organ, the corpus cardiacum, suggesting that the DH neuroendocrine system is conserved in Lepidoptera. By injection of chemically synthetic DH and anti-FXPRLa antibody into female pupae, we revealed that not only does the Orgyia DH induce embryonic diapause, but also that this neuropeptide induces seasonal polyphenism, participating in the hypertrophy of follicles and ovaries. In addition, the other four FXPRLa also induced embryonic diapause in O. thyellina, but not in Bombyx mori. This is the first study showing that a neuropeptide has a pleiotropic effect in seasonal reproductive polyphenism to accomplish seasonal adaptation. We also show that a novel factor (i.e., the DH neuropeptide) acts as an important inducer of seasonal polyphenism underlying a life-history tradeoff. Furthermore, we speculate that there must be evolutionary conservation and diversification in the neuroendocrine systems of two lepidopteran genera, Orgyia and Bombyx, in order to facilitate the evolution of coregulated life-history traits and tradeoffs. PMID:21887383

Uehara, Hiroshi; Senoh, Yukiko; Yoneda, Kyohei; Kato, Yoshiomi; Shiomi, Kunihiro

2011-01-01

337

An FXPRLamide neuropeptide induces seasonal reproductive polyphenism underlying a life-history tradeoff in the tussock moth.  

PubMed

The white spotted tussock moth, Orgyia thyellina, is a typical insect that exhibits seasonal polyphenisms in morphological, physiological, and behavioral traits, including a life-history tradeoff known as oogenesis-flight syndrome. However, the developmental processes and molecular mechanisms that mediate developmental plasticity, including life-history tradeoff, remain largely unknown. To analyze the molecular mechanisms involved in reproductive polyphenism, including the diapause induction, we first cloned and characterized the diapause hormone-pheromone biosynthesis activating neuropeptide (DH-PBAN) cDNA encoding the five Phe-X-Pro-Arg-Leu-NH(2) (FXPRLa) neuropeptides: DH, PBAN, and ?-, ?-, and ?-SGNPs (subesophageal ganglion neuropeptides). This gene is expressed in neurosecretory cells within the subesophageal ganglion whose axonal projections reach the neurohemal organ, the corpus cardiacum, suggesting that the DH neuroendocrine system is conserved in Lepidoptera. By injection of chemically synthetic DH and anti-FXPRLa antibody into female pupae, we revealed that not only does the Orgyia DH induce embryonic diapause, but also that this neuropeptide induces seasonal polyphenism, participating in the hypertrophy of follicles and ovaries. In addition, the other four FXPRLa also induced embryonic diapause in O. thyellina, but not in Bombyx mori. This is the first study showing that a neuropeptide has a pleiotropic effect in seasonal reproductive polyphenism to accomplish seasonal adaptation. We also show that a novel factor (i.e., the DH neuropeptide) acts as an important inducer of seasonal polyphenism underlying a life-history tradeoff. Furthermore, we speculate that there must be evolutionary conservation and diversification in the neuroendocrine systems of two lepidopteran genera, Orgyia and Bombyx, in order to facilitate the evolution of coregulated life-history traits and tradeoffs. PMID:21887383

Uehara, Hiroshi; Senoh, Yukiko; Yoneda, Kyohei; Kato, Yoshiomi; Shiomi, Kunihiro

2011-01-01

338

Pre-treatment fertility counseling and fertility preservation improve quality of life in reproductive age women with cancer  

PubMed Central

Background The post-treatment quality of life (QOL) impacts of receiving pre-cancer-treatment infertility counseling and of pursuing fertility preservation have not been described in large-scale studies of reproductive age women with cancer. Methods 1041 women diagnosed between the ages of 18 and 40 responded to a retrospective survey and reported whether they received infertility counseling before cancer treatment and whether they took action to preserve fertility. Five cancer types were included: leukemia, Hodgkins disease, non-Hodgkin lymphoma, breast cancer, and gastrointestinal cancer. Validated QOL scales were used: Decision Regret Score (DRS), Satisfaction with Life Scale (SWLS), and World Health Organization QOL BREF (WHOQOL-BREF). Results 560 women (61%) whose treatment could affect fertility were counseled by the oncology team, 45 (5%) were counseled by fertility specialists, 36 (4%) took action to preserve fertility. Pre-treatment infertility counseling by a fertility specialist and an oncologist resulted in lower regret than counseling by an oncologist alone (8.4 vs. 11.0, P<0.0001). The addition of fertility preservation (6.6 vs. 11.0, P<0.0001) was also associated with even lower regret scores than counseling by an oncologist alone.. Further improvements were similarly seen in SWLS with the addition of fertility specialist counseling (23.0 vs. 19.8, P=0.09) or preserving fertility (24.0 vs. 19.0, P=0.05). Conclusions Receiving specialized counseling about reproductive loss and pursuing fertility preservation is associated with less regret and greater QOL for survivors, yet few patients are exposed to this potential benefit. Reproductive aged women should have expert counseling and be given the opportunity to make active decisions about preserving fertility. PMID:21887678

Letourneau, Joseph M; Ebbel, Erin E; Katz, Patricia P; Katz, Audra; Ai, Wei Z; Chien, A Jo; Melisko, Michelle E; Cedars, Marcelle I; Rosen, Mitchell P

2011-01-01

339

6. DETAIL OF VERTICAL LIFT SPAN AND FIXED SPAN IMMEDIATELY ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

6. DETAIL OF VERTICAL LIFT SPAN AND FIXED SPAN IMMEDIATELY NORTH OF VERTICAL LIFT SPAN, LOOKING SOUTHEAST. - Shippingsport Bridge, Spanning Illinois River at State Route 51, La Salle, La Salle County, IL

340

Phytoseiid mites in protected crops: the effect of humidity and food availability on egg hatch and adult life span of Iphiseius degenerans, Neoseiulus cucumeris, N. californicus and Phytoseiulus persimilis (Acari: Phytoseiidae).  

PubMed

The effect of relative humidity on egg hatch success for Iphiseius degenerans, Neoseiulus californicus and N. cucumeris was described by a binomial model with a parallel slope. The shape of the response differed for Phytoseiulus persimilis and a model with separate parameters gave a significantly better fit. Fitted response curves showed that I. degenerans, N. cucumeris, N. californicus and P. persimilis were ranked by decreasing tolerance to low humidity, with egg mortalities of < 0.5, 3, 12 and 16% respectively at 75-80% RH at 20 degrees C. Egg stage duration for I. degenerans and N. cucumeris was unaffected over the range 60-82% RH. For N. californicus and P. persimilis egg duration was significantly longer at 60 and 70% than for either 82 or 90% RH. No effect of relative humidity was found on the mean life span of adult females when food was available continuously to the mites. N. californicus lived significantly longer (58 days after the first egg was laid) than the other species. No significant difference was observed in mean life span between adult females of I. degenerans and N. cucumeris (25 and 28 days respectively). The mean life span of adult female P. persimilis (19 days) was significantly shorter than the other species. In the absence of both food and water, the survival of adult female mites was reduced to 2-4 days. Survival time was at least doubled when free water was available in the absence of food. Mean survival of adult female mites with water but without food was 10 days for N. cucumeris, 18 days for N. californicus, 6 days for P. persimilis and 4 days for I. degenerans. Survival of adult female N. cucumeris and N. californicus was increased significantly, to 20 and 22 days respectively, when fungal hyphae were present along with water but in the absence of other food. PMID:15139268

De Courcy Williams, Michael E; Kravar-Garde, Lidija; Fenlon, John S; Sunderland, Keith D

2004-01-01

341

Variability in Reproductive Success Viewed From a Life-History Perspective in Baboons  

E-print Network

ALTMANN1,3,4 * AND SUSAN C. ALBERTS2,3 1 Department of Ecology and Evolutionary Biology, Princeton humans, mature slowly and have low fertility during a relatively long life. As data have accumulated into the evolution of this slow life-history style of primates. However, in order to understand selection pressures

Alberts, Susan C

342

PLASTICITY AND CANALIZATION OF INSECT REPRODUCTION: TESTING ALTERNATIVE MODELS OF LIFE HISTORY TRANSITIONS  

Microsoft Academic Search

Life histories may show phases of both plasticity and canalization in response to feeding rate. Models for life history canalization and plasticity postulate a threshold for initiation of canalized developmental events. Some models postulate adaptive plasticity, whereas others postulate nonadaptive plasticity that results from environmental modulation of fixed development. These models have been tested by changing feeding rate at various

Steven A. Juliano; Jennifer R. Olson; Ebony G. Murrell; John D. Hatle

2004-01-01

343

Insulin-like growth factor-I extends in vitro replicative life span of skeletal muscle satellite cells by enhancing G1/S cell cycle progression via the activation of phosphatidylinositol 3'-kinase/Akt signaling pathway  

NASA Technical Reports Server (NTRS)

Interest is growing in methods to extend replicative life span of non-immortalized stem cells. Using the insulin-like growth factor I (IGF-I) transgenic mouse in which the IGF-I transgene is expressed during skeletal muscle development and maturation prior to isolation and during culture of satellite cells (the myogenic stem cells of mature skeletal muscle fibers) as a model system, we elucidated the underlying molecular mechanisms of IGF-I-mediated enhancement of proliferative potential of these cells. Satellite cells from IGF-I transgenic muscles achieved at least five additional population doublings above the maximum that was attained by wild type satellite cells. This IGF-I-induced increase in proliferative potential was mediated via activation of the phosphatidylinositol 3'-kinase/Akt pathway, independent of mitogen-activated protein kinase activity, facilitating G(1)/S cell cycle progression via a down-regulation of p27(Kip1). Adenovirally mediated ectopic overexpression of p27(Kip1) in exponentially growing IGF-I transgenic satellite cells reversed the increase in cyclin E-cdk2 kinase activity, pRb phosphorylation, and cyclin A protein abundance, thereby implicating an important role for p27(Kip1) in promoting satellite cell senescence. These observations provide a more complete dissection of molecular events by which increased local expression of a growth factor in mature skeletal muscle fibers extends replicative life span of primary stem cells than previously known.

Chakravarthy, M. V.; Abraha, T. W.; Schwartz, R. J.; Fiorotto, M. L.; Booth, F. W.

2000-01-01

344

Reproductive success in presenescent common gulls (Larus canus): the importance of the last year of life.  

PubMed

Survival selection against individuals of inferior quality (measured as breeding success) has been proposed to account for the increase in average reproductive success with advancing age in presenescent birds. This so-called selection hypothesis relies on quality-dependent survival. In the present breeding performance study of common gulls, Larus canus, this assumption was not verified. In particular, omitting the last breeding year from the analysis resulted in the disappearance of the correlation between breeding success and survival. A positive correlation in the full dataset was thus solely based on the poor breeding success of ultimate breeders. Indeed, presenescent individuals were shown to have a specifically low breeding success in their terminal breeding event. The poor success of ultimate breeders thus reflects an abruptly declined condition rather than the birds' overall quality. A comparison of the survival of poor and good performers, involving last-time breeders, thus needs not to be a proper test of the selection hypothesis. Longitudinal analysis revealed a steady increase of individual breeding success until the tenth breeding year. The results suggest that an increase of breeding success with age often found in cross-sectional analyses is primarily a result of age-related improvements of competence and/or increased reproductive effort. PMID:15451696

Rattiste, Kalev

2004-10-01

345

Reproductive success in presenescent common gulls (Larus canus): the importance of the last year of life.  

PubMed Central

Survival selection against individuals of inferior quality (measured as breeding success) has been proposed to account for the increase in average reproductive success with advancing age in presenescent birds. This so-called selection hypothesis relies on quality-dependent survival. In the present breeding performance study of common gulls, Larus canus, this assumption was not verified. In particular, omitting the last breeding year from the analysis resulted in the disappearance of the correlation between breeding success and survival. A positive correlation in the full dataset was thus solely based on the poor breeding success of ultimate breeders. Indeed, presenescent individuals were shown to have a specifically low breeding success in their terminal breeding event. The poor success of ultimate breeders thus reflects an abruptly declined condition rather than the birds' overall quality. A comparison of the survival of poor and good performers, involving last-time breeders, thus needs not to be a proper test of the selection hypothesis. Longitudinal analysis revealed a steady increase of individual breeding success until the tenth breeding year. The results suggest that an increase of breeding success with age often found in cross-sectional analyses is primarily a result of age-related improvements of competence and/or increased reproductive effort. PMID:15451696

Rattiste, Kalev

2004-01-01

346

Communicating Employability Enhancement throughout the Life-Span: A National Intervention Program Aimed at Combating Age-Related Stereotypes at the Workplace  

ERIC Educational Resources Information Center

The stimulation of lifelong employability of employees is one of today's challenges in all sectors of the Dutch society. In this article, we will outline the historical context of the life-long employability issue in the Netherlands, and provide an overview of current business responses to the issue. We will discuss key obstacles for improving

van Selm, Martine; Van der Heijden, Beatrice I. J. M.

2013-01-01

347

The structure of a thermophilic archaeal virus shows a dsDNA viral capsid type that spans all domains of life  

SciTech Connect

Of the three domains of life (Eukarya, Bacteria, and Archaea), the least understood is Archaea and its associated viruses. Many Archaea are extremophiles, with species that are capable of growth at some of the highest temperatures and extremes of pH of all known organisms. Phylogenetic rRNA-encoding DNA analysis places many of the hyperthermophilic Archaea (species with an optimum growth >80C) at the base of the universal tree of life, suggesting that thermophiles were among the first forms of life on earth. Very few viruses have been identified from Archaea as compared to Bacteria and Eukarya. We report here the structure of a hyperthermophilic virus isolated from an archaeal host found in hot springs in Yellowstone National Park. The sequence of the circular double-stranded DNA viral genome shows that it shares little similarity to other known genes in viruses or other organisms. By comparing the tertiary and quaternary structures of the coat protein of this virus with those of a bacterial and an animal virus, we find conformational relationships among all three, suggesting that some viruses may have a common ancestor that precedes the division into three domains of life >3 billion years ago.

G. Rice; L. Tang; K. Stedman; F. Roberto; J. Spuhler; E. Gillitzer; J. E. Johnson; T. Douglas; M. Young

2004-05-01

348

Designing prospective cohort studies for assessing reproductive and developmental toxicity during sensitive windows of human reproduction and development--the LIFE Study.  

PubMed

The relationship between the environment and human fecundity and fertility remains virtually unstudied from a couple-based perspective in which longitudinal exposure data and biospecimens are captured across sensitive windows. In response, we completed the LIFE Study with methodology that intended to empirically evaluate a priori purported methodological challenges: implementation of population-based sampling frameworks suitable for recruiting couples planning pregnancy; obtaining environmental data across sensitive windows of reproduction and development; home-based biospecimen collection; and development of a data management system for hierarchical exposome data. We used two sampling frameworks (i.e., fish/wildlife licence registry and a direct marketing database) for 16 targeted counties with presumed environmental exposures to persistent organochlorine chemicals to recruit 501 couples planning pregnancies for prospective longitudinal follow-up while trying to conceive and throughout pregnancy. Enrolment rates varied from <1% of the targeted population (n =?424,423) to 42% of eligible couples who were successfully screened; 84% of the targeted population could not be reached, while 36% refused screening. Among enrolled couples, ? 85% completed daily journals while trying; 82% of pregnant women completed daily early pregnancy journals, and 80% completed monthly pregnancy journals. All couples provided baseline blood/urine samples; 94% of men provided one or more semen samples and 98% of women provided one or more saliva samples. Women successfully used urinary fertility monitors for identifying ovulation and home pregnancy test kits. Couples can be recruited for preconception cohorts and will comply with intensive data collection across sensitive windows. However, appropriately sized sampling frameworks are critical, given the small percentage of couples contacted found eligible and reportedly planning pregnancy at any point in time. PMID:21819423

Buck Louis, Germaine M; Schisterman, Enrique F; Sweeney, Anne M; Wilcosky, Timothy C; Gore-Langton, Robert E; Lynch, Courtney D; Boyd Barr, Dana; Schrader, Steven M; Kim, Sungduk; Chen, Zhen; Sundaram, Rajeshwari

2011-09-01

349

Population dynamics of noncytoplasmic incompatibility-inducing Wolbachia in Nilaparvata lugens and its effects on host adult life span and female fitness.  

PubMed

Wolbachia are bacteria that live intracellularly in a wide variety of arthropods. They are maternally inherited and can affect both reproduction and fitness of its host. When infected males mate with uninfected females or females infected by a different Wolbachia strain, there is often a failure of karyogamy, which is usually attributed to cytoplasmic incompatibility (CI). We measured the strength of CI induced by Wolbachia and the fitness effects in three Chinese populations of the brown planthopper Nilaparvata lugens from Hainan, Yunnan, and Guangxi provinces, respectively. No evidence for CI was found in any of the populations, whereas an enhanced fecundity and shortened longevity were observed only in the Hainan population. The infection density was significantly higher in the Hainan population than in the Guangxi population. The Wolbachia strain infecting the three populations appeared to be the same based on the nucleotide sequence of the wsp gene. Therefore, the variable effects of Wolbachia on host fitness seem to be the result of differences in the host genetic background and Wolbachia infection density. The ability of the non-CI-inducing Wolbachia to maintain themselves in their hosts may be attributed to their positive effects on host fecundity and efficient maternal transmission. PMID:22182545

Zhang, Hui; Zhang, Kai-Jun; Hong, Xiao-Yue

2010-12-01

350

Fungal plant endosymbionts alter life history and reproductive success of aphid predators.  

PubMed

Endosymbionts occur in most plant species and may affect interactions among herbivores and their predators through the production of toxic alkaloids. Here, we ask whether effects of mycotoxins produced by the symbiosis of the fungal endophyte Neotyphodium lolii and the grass Lolium perenne are transmitted to the aphidophagous ladybird Coccinella septempunctata when feeding on cereal aphids Rhopalosiphum padi on infected plants. The larval development of coccinellids was extended, while their survival was reduced when feeding exclusively on aphids from infected plants. Ladybirds developing on aphids from infected plants showed reduced fecundity and impaired reproductive performance. Body size and symmetries of ladybird adults were not affected by the endophytes. Consistently strong, negative effects of endophytes on the lifetime performance of ladybirds indicates that mycotoxins are transmitted along food chains, causing significant damage for top predators. Such cascading effects will influence the population dynamics of aphid predators in the long term and could feedback to the primary plant producers. PMID:16720406

de Sassi, Claudio; Mller, Christine B; Krauss, Jochen

2006-05-22

351

Bioscience-bioethics and life factors affecting reproduction with special reference to the Indigenous Australian population.  

PubMed

The demand for equality of recognition or respect is the dominant passion of modernity. The 20th century experienced a giant leap in technological inventiveness and ruthless use of technological power. In the 21st century, human welfare and environmental wellbeing demand fundamental political appraisal. We have the means, if we choose, to eradicate poverty and to responsibly protect the global environment. However, economic, political and cultural systems act to differentially allocate the benefits and risks for growth between socioeconomic groups. For example, it is a matter of pride that the neonatal mortality rate in affluent societies has dropped substantially since the late 1970s. However, the level of infant mortality (three times the national average) and low birthweight (13%) among the Indigenous Australian population is the highest in the country. With hindsight we now know that is the inevitable legacy of Australia's colonial history. Chronic physical and psychological stress is recognized as an important etiological factor in many lifestyle diseases of the cardiovascular, immune and reproductive systems. Diseases of adaptation are further advanced by non-adaptive lifestyle choices, depression, alcoholism and other drug dependencies. This review describes the principles of bioscience ethics and targets equity issues as they affect human reproduction across generations with particular reference to the Indigenous population of Australia. The review also considers ways we may advance global and cultural maturity from the Indigenous Australian perspective and proposes an ecologically based model of preventative care. If we are to embrace fundamental social change and protect future children without threatening parents' basic freedoms, then new beliefs and priorities--based on a compassionate understanding of biological systems--must evolve from the general public. Belief in human rights arising from a sense of human dignity is a collective outcome originating from individual commitment. The golden rule; that is, Nature's principle of reciprocity, is fundamental in bridging the gap between knowledge and effective action. PMID:15798014

Pollard, Irina

2005-04-01

352

Toxicity of copper-spiked sediments to Tubifex tubifex (Oligochaeta, Tubificidae): Comparison of the 28-day reproductive bioassay with an early-life-stage bioassay  

Microsoft Academic Search

Two sediment bioassay methods using Tubifex tubifex (Mueller, 1774) as the test species were compared. The first was an adult reproduction test, the second an early-life-stage survival test. The duration of both bioassays is 28 d and the amount of work required was similar; they may be useful alternatives to each other in different circumstances (e.g., the early life stage

Martina Vecchi; A. Pasteris; G. Bonomi; T. B. Reynoldson

1999-01-01

353

Male personality, life-history strategies and reproductive success in a promiscuous mammal  

E-print Network

L O G Y 1599 Keywords: bighorn sheep; boldness; docility; heritability; longevity; Ovis canadensis-term pedigree we estimated indices of boldness and docility for 105 bighorn sheep rams (Ovis canadensis), born personality traits and life-history strategies. Here we use a long-term study of bighorn sheep (Ovis

Festa-Bianchet, Marco

354

Multiple paternity, male reproductive success, hormonal regulation of fertility, and the evolution of life-histories  

Microsoft Academic Search

The life-history strategy that an individual exhibits is shaped by trade-offs between maximizing the number of viable offspring it produces and retaining enough resources to ensure its own survival. The balance between these two aspects is strongly influenced by the environmental conditions the individual experiences in its lifetime and can be affected by the effort an individual puts into each

Megan Brianne Manes

2011-01-01

355

Japan turns pro-life: recent change in reproductive health policy and challenges by new technologies  

PubMed Central

Japan, known as a pro-choice country in terms of abortion, is currently facing the increase of selective abortions thanks to new prenatal screening. Efforts to restrict proliferation of new technology has not been successful and it is likely that Japan will turn pro-life by strictly enforcing the Maternity Protection Act (MPA), which prohibits abortions due to fetal cause. PMID:24639978

Okamoto, Etsuji

2014-01-01

356

Minimal spanning forests  

E-print Network

Minimal spanning forests on infinite graphs are weak limits of minimal spanning trees from finite subgraphs. These limits can be taken with free or wired boundary conditions and are denoted FMSF (free minimal spanning forest) and WMSF (wired minimal spanning forest), respectively. The WMSF is also the union of the trees that arise from invasion percolation started at all vertices. We show that on any Cayley graph where critical percolation has no infinite clusters, all the component trees in the WMSF have one end a.s. In $\\mathbb{Z}^d$ this was proved by Alexander [Ann. Probab. 23 (1995) 87--104], but a different method is needed for the nonamenable case. We also prove that the WMSF components are ``thin'' in a different sense, namely, on any graph, each component tree in the WMSF has $p_{\\mathrm{c}}=1$ a.s., where $p_{\\mathrm{c}}$ denotes the critical probability for having an infinite cluster in Bernoulli percolation. On the other hand, the FMSF is shown to be ``thick'': on any connected graph, the union of the FMSF and independent Bernoulli percolation (with arbitrarily small parameter) is a.s. connected. In conjunction with a recent result of Gaboriau, this implies that in any Cayley graph, the expected degree of the FMSF is at least the expected degree of the FSF (the weak limit of uniform spanning trees). We also show that the number of infinite clusters for Bernoulli($p_{\\mathrm{u}}$) percolation is at most the number of components of the FMSF, where $p_{\\mathrm{u}}$ denotes the critical probability for having a unique infinite cluster. Finally, an example is given to show that the minimal spanning tree measure does not have negative associations.

Russell Lyons; Yuval Peres; Oded Schramm

2004-12-13

357

Geographical variation in reproductive ageing patterns and life-history strategy of a short-lived passerine bird.  

PubMed

We investigated differences in ageing patterns in three measures of breeding performance in populations of barn swallows Hirundo rustica L. from Spain and Denmark differing in breeding latitude and hence migration distance and duration of the breeding season. We found differences in ageing patterns between populations. Generally, young (i.e. yearling) and old females (i.e. ?5years of age) laid their first eggs later and produced smaller clutches than middle-aged females (i.e. 2-4years of age) in both populations. The southernmost population (i.e. Spanish) showing the shorter migratory distance experienced a greater within-individual increase in timing of breeding and clutch size in early life and a greater within-individual decrease in laying date but not in clutch size during senescence compared with the northernmost population (i.e. Danish). We also found that the number of fledglings produced annually was related to the age of the two members of the breeding pairs with pairs composed of young and old females performing less well than breeding pairs composed of middle-aged females. We did not find reproductive senescence for the age of the male while controlling for the age of the female on the number of fledglings produced annually by the breeding pair. Differential survival between individuals did not explain age effects on laying date or annual clutch size in neither population. However, the increase in the number of fledglings produced annually with age was partly explained by the disappearance of poor-quality members of the pairs, mainly poor-quality males. Age-related breeding success (i.e. number of fledglings) was similar for barn swallows from Spain and Denmark. Therefore, the study of ageing patterns and life-history strategies in free-ranging animals from more than a single population can throw new light on life-history theory, population dynamics and evolutionary studies of senescence. PMID:22994532

Balbontn, Javier; Mller, A P; Hermosell, I G; Marzal, A; Reviriego, M; de Lope, F

2012-11-01

358

C-SPAN Classroom  

NSDL National Science Digital Library

Over the past several decades, C-SPAN has brought many hours of fascinating programming to the generally curious. Many teachers have used their programming to edify their students about various aspects of US government, and now C-SPAN has created this very nice site to complement those informal activities. The formal mission of the C-SPAN Classroom site is "to enhance the teaching of Civics & U.S. Government through C-SPAN's primary source programming." Visitors can start their journey by viewing the "Clip of the Week", and then looking through the other thematic sections on the site, which include "Principles of Government", "Legislative Branch", and "Political Participation". Along with each clip, users can also view a short clip description, and take advantage of the discussion questions as well. Visitors will need to complete a short free registration form to access all of the clips, and this only takes a few minutes. This site is quite a delight, and for anyone who teaches civics and related fields, it will most likely become an essential online resource.

359

New prospects for a prolonged functional life-span of artificial hip joints by using the material combination polyethylene/aluminium oxide ceramin/metal.  

PubMed

Investigations over the years have shown that the mirror-finished Al2O3 ceramic is a much more suitable frictional counterpart to ultrahigh molecular weight (UHMW) polyethylene than metal. Despite the extremely gread hardness difference between polyethylene and Al2O3 ceramic, a considerable lower wear rate is obtained for the polyethylene socked with this new low-friction material combination. The unexpectedly favorable tribological behavior of this ceramic material in contact with polyethylene may be attributed to the following factors: better values for corrosion resistance characteristics, wettability with liquids, surfact gloss, hardness, and scratch resistance of the ceramic material in comparison with those of the hitherto used metallic implant materials (AISI-316L steel or cast Co-Cr-Mo alloy). It appears that, by using this new combination of materials for the socket and the ball, it will be possible to prolong the service life of artificial hip joints considerably without having effecy any fundamental changes in the present design and implantation principle retaining the hitherto used anchorage shaft made of wrought Co-Ni-Cr-Mo-Ti alloy Protasul-10 of extremely high corrosion fatigue strength. PMID:559675

Semlitsch, M; Lehmann, M; Weber, H; Doerre, E; Willert, H G

1977-07-01

360

Evolution of monogamy, paternal investment, and female life history in Peromyscus.  

PubMed

The timing of reproductive development and associated trade-offs in quantity versus quality of offspring produced across the life span are well documented in a wide range of species. The relation of these aspects of maternal life history to monogamy and paternal investment in offspring is not well studied in mammals, due in part to the rarity of the latter. By using five large, captive-bred populations of Peromyscus species that range from promiscuous mating with little paternal investment (P. maniculatus bairdii) to social and genetic monogamy with substantial paternal investment (P. californicus insignis), we modeled the interaction between monogamy and female life history. Monogamy and high paternal investment were associated with smaller litter size, delayed maternal reproduction that extended over a longer reproductive life span, and larger, higher quality offspring. The results suggest monogamy and paternal investment can alter the evolution of female life-history trajectories in mammals. PMID:22545763

Jaarevi?, Eldin; Bailey, Drew H; Crossland, Janet P; Dawson, Wallace D; Szalai, Gabor; Ellersieck, Mark R; Rosenfeld, Cheryl S; Geary, David C

2013-02-01

361

C-SPAN Classroom  

NSDL National Science Digital Library

The C-SPAN in the classroom website is geared toward teachers of political science - or specifically U.S. Government. The site is split into six segments: Principles of Government, the Constitution, Political Participation and each of the three branches of government. Each of these sections features video clips, and questions for class discussion. Free site membership is available, but not required to use the site. Some additional content and services are available with membership.

2006-11-25

362

What Deficits in Sexual and Reproductive Health Knowledge Exist among Women with Cystic Fibrosis? A Systematic Review  

ERIC Educational Resources Information Center

The life span of patients with cystic fibrosis (CF) continues to extend due to advances in treatments and care. The rate of pregnancy for female patients with CF has also continued to rise. The purpose of this study was to systematically review the available literature on female patients with CF and their knowledge of sexual and reproductive

Gage, L. Ashley

2012-01-01

363

Effects of trilostane and fipronil on the reproductive axis in an early life stage of the Japanese medaka (Oryzias latipes).  

PubMed

Given the critical role of the hypothalamic-pituitary-gonadal (HPG) axis, it is conceivable that perturbations at any point along this axis can potentially affect reproduction in fish and other vertebrates. We investigated the effects of a 3?-hydroxysteroid dehydrogenase (3?-HSD) inhibitor, trilostane (TRI), and a gamma-aminobutyric acid (GABA)-receptor antagonist, fipronil (FIP), on the HPG axis using an early life stage of the Japanese medaka. The newly hatched larvae were exposed to TRI (100, 300 and 1000 ?g/L) and FIP (3, 10 and 30 ?g/L), respectively, until 28 days post-hatching. Exposure to TRI decreased the body length in males, whereas FIP inhibited growth in both sexes. The induction of steroidogenesis-regulating genes (including 3?-hsd) in males exposed to TRI, accompanied by increased vtg and er transcription, indicating a compensatory response to the presumed 3?-HSD inhibition. These compensatory responses were not observed in TRI-treated females. Regarding FIP exposure, the GABA blocker resulted in the down-regulation of fshr and lhr. A compensatory up-regulation of steroidogenesis-regulating genes partially explained the elevated transcripts of vtg genes in both males and females after FIP exposure. These results suggest that both the inhibition of 3?-HSD and the antagonism of GABA receptors are relevant modes of endocrine disruption that could impact the normal regulation of the HPG axis. PMID:24777665

Sun, Liwei; Jin, Rong; Peng, Zuhua; Zhou, Qiwei; Qian, Haifeng; Fu, Zhengwei

2014-08-01

364

Terminal Investment: Individual Reproduction of Ant Queens Increases with Age  

PubMed Central

The pattern of age-specific fecundity is a key component of the life history of organisms and shapes their ecology and evolution. In numerous animals, including humans, reproductive performance decreases with age. Here, we demonstrate that some social insect queens exhibit the opposite pattern. Egg laying rates of Cardiocondyla obscurior ant queens increased with age until death, even when the number of workers caring for them was kept constant. Cardiocondyla, and probably also other ants, therefore resemble the few select organisms with similar age-specific reproductive investment, such as corals, sturgeons, or box turtles (e.g., [1]), but they differ in being more short-lived and lacking individual, though not social, indeterminate growth. Furthermore, in contrast to most other organisms, in which average life span declines with increasing reproductive effort, queens with high egg laying rates survived as long as less fecund queens. PMID:22509399

Heinze, Jurgen; Schrempf, Alexandra

2012-01-01

365

Life-span effects of ionizing radiation in the beagle dog: A summary account of four decades of research funded by the US Department of Energy and its predecessor agencies  

SciTech Connect

Nearly 40 years ago, the US Atomic Energy Commission made a far- reaching commitment to the support of life-span radiation-effects studies in a relatively long-lived animal, the beagle dog. Something in the range of 200 million dollars has already been spent on a group of closely related experiments, many of which are only now coming to fruition. Responsible fiscal management of these studies, directed toward securing an optimum return from past investments, and toward creative planning of future directions, requires a comprehensive view of this total effort. This report is designed to provide that comprehensive view. This is primarily intended as a research management document. Evaluation and interpretation are tasks for those directly involved in conducting these experiments. The limited objective of the present document is to describe what has been done, to give some of the background for why it was done, to describe results already realized and applications that have been made of these results -- all in a manner designed to display the total effort rather than piecemeal details. While proposing no specific answers to the questions ''Where do we go from here.''it is hoped that the document will provide a basis for approaching that question in an informed manner. The maintenance of a continuity of scientific understanding and direction in these experiments, which often continue beyond the initiating investigators' working life, is no small part of the problem involved in conducting these experiments.

Thompson, R.C.

1989-01-01

366

Reproduction, survival, and life table parameters of the predatory mite Cheyletus malaccensis (Acari: Cheyletidae) at various constant temperatures.  

PubMed

Reproduction, survival, and life table parameters of the predatory mite Cheyletus malaccensis Oudemans were evaluated at six constant temperatures: 17.5, 20, 25, 30, 32.5 and 35C, feeding on Tyrophagus putrescentiae (Schrank). Preoviposition period of fertilized and virgin females varied with temperature from ca. 9 days at 17.5C to ca. 1.5 day at 32.5C and then increased to ca. 3 days at 35C. Virgin female oviposition period was significantly shorter than for fertilized females at the temperatures examined with the exception of 17.5C. The mean total number of eggs per fertilized (169.7 6.6) and virgin female (60.7 4.3) was highest at the temperature of 30C. The data indicated a significant positive and nearly doubling effect of fertilization on female fecundity at the temperatures examined with the exception of 17.5C. Age-specific fecundity was described by a temperature dependent model from which the maximum daily fecundity rate was estimated for fertilized and virgin females at 10.3 (at 30C) and 6.8 (at 32.5C) eggs/female, respectively. Virgin female longevity was significantly shorter than for fertilized females at 20, 30 and 32.5C, and decreased from ca. 57 days at 17.5C to ca. 17 days at 35C. The Weibull function that was used to describe the age specific survival of fertilized and virgin females produced excellent fits to the survival data. Estimates of intrinsic rate of increase, net reproductive rate, mean generation time, doubling time and finite rate of increase, were obtained. The r(m) value increased with temperature from 0.03 (day(-1)) at 17.5C to 0.21 (day(-1)) at 32.5C, after which it decreased to 0.15 (day(-1)) at 35C. These data indicate that C. malaccensis can reproduce at temperatures between 17.5 and 35C and can be used for biological control of astigmatid mites within the temperature range where the pest occurs. PMID:21287248

Palyvos, Nickolas E; Emmanouel, Nickolas G

2011-06-01

367

Evolution of trade-offs between sexual and asexual phases and the role of reproductive plasticity in the genetic architecture of aphid life histories.  

PubMed

Life-history theory postulates that evolution is constrained by trade-offs (i.e., negative genetic correlations) among traits that contribute to fitness. However, in organisms with complex life cycles, trade-offs may drastically differ between phases, putatively leading to different evolutionary trajectories. Here, we tested this possibility by examining changes in life-history traits in an aphid species that alternates asexual and sexual reproduction in its life cycle. The quantitative genetics of reproductive and dispersal traits was studied in 23 lineages (genotypes) of the bird cherry-oat aphid Rhopalosiphum padi, during both the sexual and asexual phases, which were induced experimentally under specific environmental conditions. We found large and significant heritabilities (broad-sense) for all traits and several negative genetic correlations between traits (trade-offs), which are related to reproduction (i.e., numbers of the various sexual or asexual morphs) or dispersal (i.e., numbers of winged or wingless morphs). These results suggest that R. padi exhibits lineage specialization both in reproductive and dispersal strategies. In addition, we found important differences in the structure of genetic variance-covariance matrices (G) between phases. These differences were due to two large, negative genetic correlations detected during the asexual phase only: (1) between fecundity and age at maturity and (2) between the production of wingless and winged parthenogenetic females. We propose that this differential expression in genetic architecture results from a reallocation scheme during the asexual phase, when sexual morphs are not produced. We also found significant G x E interaction and nonsignificant genetic correlations across phases, indicating that genotypes could respond independently to selection in each phase. Our results reveal a rather unique situation in which the same population and even the same genotypes express different genetic (co)variation under different environmental conditions, driven by optimal resource allocation criteria. PMID:19473379

Nespolo, Roberto F; Halkett, Fabien; Figueroa, Christian C; Plantegenest, Manuel; Simon, Jean-Christophe

2009-09-01

368

Reproductive Rights and Chinese Women  

E-print Network

Reproductive Rights and Chinese Women Kelly Vogel "If the family planning program posed a conflict in fertility and life expectancy = global problem (40s and 50s) #12;Defining "Reproductive Rights" As defined by the UNFPA... Reproductive and sexual health as a component of overall health Reproductive decision making

New Hampshire, University of

369

Self-Discrepancy Across the Life Span  

Microsoft Academic Search

This study examined the developmental trajectory of self-discrepancies in adulthood and the role of self-discrepancies in the maintenance of psychological well-being. One hundred fourteen adults completed mailed surveys that assessed physical health, actual self and ideal self, depression, anxiety, self-esteem, and self-discrepancy. Examination of age differences in actual self and ideal self assessments showed that ideal self ratings converged with

Susan M. Heidrich

1999-01-01

370

Getting Serious Play: Life Span Career Education  

ERIC Educational Resources Information Center

Canada's $76.5 billion annual investment in education is paying dividends. A recent international survey ranked Canadian students "second" in reading literacy, "fifth" in mathematics and "fifth" in science. For nations and individuals alike, such mastery is intrinsic to success in the new knowledge economy. Yet, mastering these academic skills in

Jarvis, Phil; Esbin, Howard

2006-01-01

371

Autobiographical Memory from a Life Span Perspective  

ERIC Educational Resources Information Center

This comparative study (i.e., three age groups, three measures) explores the distribution of retrospective and prospective autobiographical memory data across the lifespan, in particular the bump pattern of disproportionally higher recall of memories from the ages 10 to 30, as generally observed in older age groups, in conjunction with the

Schroots, Johannes J. F.; van Dijkum, Cor; Assink, Marian H. J.

2004-01-01

372

Touch Therapies across the Life Span  

Microsoft Academic Search

The Ayur-Veda, the earliest known medical text from India (around 1800 b.c.), lists touch therapy (massage therapy), diet, and exercise as primary healing practices of that time. As Jules Older notes,\\u000a even the English word shampoo comes from the word champna, which is an ancient Indian word meaning to press (Older, 1982). From early times, massage has been effectively used

Tiffany M. Field

373

Life-span distributions of supermarket products  

NASA Astrophysics Data System (ADS)

We have analyzed the lifetime distributions of more than 0.7 million products sold across approximately 400 Japanese supermarkets. The distributions are well approximated by an exponential function for products with lifetimes longer than 1000 days, implying that the manufacturers' decisions about whether to continue production are purely random. However, the distributions tend to deviate from an exponential distribution for products with lifetimes shorter than 1000 days. Specifically, the distributions for food products exhibit a quicker decay in a short time scale, suggesting the existence of competing products during the initial stages of the product lifecycle. On the other hand, the distributions for toiletry products exhibit a slower decay in a short time scale.

Ueno, Hiromichi; Watanabe, Tsutomu; Takayasu, Misako

2010-04-01

374

Learning To Learn across the Life Span.  

ERIC Educational Resources Information Center

Ways to help learners of all ages to independently search out and use existing knowledge and new information to solve problems and acquire new skills is examined through 15 papers by leading experts in learning-to-learn theory and application. Papers have the following titles and authors: "The Promise of Learning to Learn" (Robert M. Smith); "How

Smith, Robert M.; And Others

375

The life span of the biosphere revisited.  

PubMed

A decade ago, Lovelock and Whitfield raised the question of how much longer the biosphere can survive on Earth. They pointed out that, despite the current fossil-fuel induced increase in the atmospheric CO2 concentration, the long-term trend should be in the opposite direction: as increased solar luminosity warms the Earth, silicate rocks should weather more readily, causing atmospheric CO2 to decrease. In their model, atmospheric CO2 falls below the critical level for C3 photosynthesis, 150 parts per million (p.p.m.), in only 100 Myr, and this is assumed to mark the demise of the biosphere as a whole. Here, we re-examine this problem using a more elaborate model that includes a more accurate treatment of the greenhouse effect of CO2, a biologically mediated weathering parameterization, and the realization that C4 photosynthesis can persist to much lower concentrations of atmospheric CO2(<10 p.p.m.). We find that a C4-plant-based biosphere could survive for at least another 0.9 Gyr to 1.5 Gyr after the present time, depending respectively on whether CO2 or temperature is the limiting factor. Within an additional 1 Gyr, Earth may lose its water to space, thereby following the path of its sister planet, Venus. PMID:11536510

Caldeira, K; Kasting, J F

376

The life span of the biosphere revisited  

NASA Astrophysics Data System (ADS)

A DECADE ago, Lovelock and Whitfield1 raised the question of how much longer the biosphere can survive on Earth. They pointed out that, despite the current fossil-fuel induced increase in the atmospheric CO2 concentration, the long-term trend should be in the opposite direction: as increased solar luminosity warms the Earth, silicate rocks should weather more readily, causing atmospheric CO2 to decrease. In their model1, atmospheric CO2 falls below the critical level for C3 photosynthesis, 150 parts per million (p.p.m.), in only 100 Myr, and this is assumed to mark the demise of the biosphere as a whole. Here, we re-examine this problem using a more elaborate model that includes a more accurate treatment of the greenhouse effect of CO2 (refs 2-4), a biologically mediated weathering parameterization, and the realization that C4 photosynthesis can persist to much lower concentrations of atmospheric CO2(<10 p.p.m.)5,6. We find that a C4-plant-based biosphere could survive for at least another 0.9 Gyr to 1.5 Gyr after the present time, depending respectively on whether CO2 or temperature is the limiting factor. Within an additional 1 Gyr, Earth may lose its water to space, thereby following the path of its sister planet, Venus.

Caldeira, Ken; Kasting, James F.

1992-12-01

377

Conflict and Cooperation across the Life Span  

E-print Network

) identified five major conflict management styles: competing, collaborating (or problem solving), avoiding, compromising, and accommodating (? Interpersonal Conflict). These five styles have been applied, adapted and validated in slightly different ways... the nature of conflict, conflict styles, intergenerational conflict management, and how younger and older adults differ in their perceptions and attributions of conflict and conflict management styles. Conceptualizing Intergenerational Conflict...

Zhang, Yan Bing

2008-01-01

378

Exceptional longevity is associated with decreased reproduction  

PubMed Central

A number of leading theories of aging, namely The Antagonistic Pleiotropy Theory (Williams, 1957), The Disposable Soma Theory (Kirkwood, 1977) and most recently The Reproductive-Cell Cycle Theory (Bowen and Atwood, 2004, 2010) suggest a tradeoff between longevity and reproduction. While there has been an abundance of data linking longevity with reduced fertility in lower life forms, human data have been conflicting. We assessed this tradeoff in a cohort of genetically and socially homogenous Ashkenazi Jewish centenarians (average age ~100 years). As compared with an Ashkenazi cohort without exceptional longevity, our centenarians had fewer children (2.01 vs 2.53, p < 0.0001), were older at first childbirth (28.0 vs 25.6, p < 0.0001), and at last childbirth (32.4 vs 30.3, p < 0.0001). The smaller number of children was observed for male and female centenarians alike. The lower number of children in both genders together with the pattern of delayed reproductive maturity is suggestive of constitutional factors that might enhance human life span at the expense of reduced reproductive ability. PMID:22199025

Tabatabaie, Vafa; Atzmon, Gil; Rajpathak, Swapnil N.; Freeman, Ruth; Barzilai, Nir; Crandall, Jill

2011-01-01

379

"Life is still going on": reproductive intentions among HIV-positive women and men in South Africa.  

PubMed

This article reports on qualitative research investigating HIV positive individuals' reproductive intentions and their influencing factors in Cape Town, South Africa. In-depth interviews were held with 61 HIV positive women and men; at the time of interview, half had been receiving antiretroviral treatment (ART) for over 6 months and half were not receiving ART. Being HIV positive modified but did not remove reproductive desires, and diversity existed in reproductive intentions. Some HIV positive individuals wished to avoid pregnancy. Fears of partner and infant infection and having a previously infected baby were important factors deterring some individuals from considering having children. There was also strongly perceived community disapproval associated with HIV and reproduction. Strong desires to experience parenthood, mediated by prevailing social and cultural norms that encouraged childbearing in society more broadly, were reported by others. Motherhood was an important component of married women's identity and important for women's social status. Family, husbands' and societal expectations for childbearing were important influences on women's reproductive intentions, for some counterbalancing HIV as a factor discouraging reproduction. There was evidence that prevention of perinatal transmission programs in combination with ART may alter women and men's attitudes in favour of childbearing. Most HIV positive women had not discussed their reproductive desires and intentions with health care providers in HIV care or general health services because of anticipated negative reactions. The few who had done so perceived the counselling environment to be mostly unsupportive of open discussion on these issues. The findings highlight the need for explicit policies recognizing reproductive rights and choice. They support the need for health counselling and service interventions that advance safer and healthier reproductive options for HIV positive individuals in this region of the world which is experiencing a generalised and advanced HIV/AIDS pandemic. PMID:17451852

Cooper, Diane; Harries, Jane; Myer, Landon; Orner, Phyllis; Bracken, Hillary; Zweigenthal, Virginia

2007-07-01

380

Characteristics of an infinite life span diploid human fibroblast cell strain and a near-diploid strain arising from a clone of cells expressing a transfected v-myc oncogene  

SciTech Connect

Diploid human fibroblasts were transfected with a plasmid carrying a v-myc oncogene linked to the neo gene or with a vector control carrying a neo gene. Drug-resistant clones were isolated and subcultured as needed. All populations went into crisis and eventually senesced. But while they were senescing, viable-appearing clones were noted among the progeny of a transfected population that expressed the v-myc oncogene. After several months, these cells began replicating more rapidly. Karyotype analysis indicated that they were clonally derived since all of them had 45 chromosomes, including 2 marker chromosomes. This cell strain was designated MSU-1.1. Similar analysis showed that cells from an earlier passage were diploid. These cells were designated MSU-1.0. The expression of v-myc is probably required for acquisition of an infinite life span, since this phenotype did not develop in populations not expressing this oncogene. However, expression of v-myc is clearly not sufficient, since all of the progeny of the clone that gave rise to the MSU-1.0 cells expressed this oncogene, but the vast majority of them senesced.

Morgan, T.L.; Dajun Yang; Fry, D.G.; Hurlin, P.J.; Kohler, S.K.; Maher, V.M.; McCormick, J.J. (Michigan State Univ., East Lansing (United States))

1991-11-01

381

An evaluation of fish early life stage tests for predicting reproductive and longer-term toxicity from plant protection product active substances.  

PubMed

The chronic toxicity of chemicals to fish is routinely assessed by using fish early life stage (ELS) test results. Fish full life cycle (FLC) tests are generally required only when toxicity, bioaccumulation, and persistence triggers are met or when there is a suspicion of potential endocrine-disrupting properties. This regulatory approach is based on a relationship between the results of fish ELS and FLC studies first established more than 35 yrs ago. Recently, this relationship has been challenged by some regulatory authorities, and it has been recommended that more substances should undergo FLC testing. In addition, a project proposal has been submitted to the Organisation for Economic Cooperation and Development (OECD) to develop a fish partial life cycle (PLC) test including a reproductive assessment. Both FLC and PLC tests are animal- and resource-intensive and technically challenging and should therefore be undertaken only if there is clear evidence that they are necessary for coming to a regulatory decision. The present study reports on an analysis of a database of paired fish ELS and FLC endpoints for plant protection product active substances from European Union draft assessment reports and the US Environmental Protection Agency Office of Pesticide Programs Pesticide Ecotoxicity Database. Analysis of this database shows a clear relationship between ELS and FLC responses, with similar median sensitivity across substances when no-observed-effect concentrations (NOECs) are compared. There was also no indication that classification of a substance as a mammalian reproductive toxicant leads to more sensitive effects in fish FLC tests than in ELS tests. Indeed, the response of the ELS tests was generally more sensitive than the most sensitive reproduction NOEC from a FLC test. This analysis indicates that current testing strategies and guidelines are fit for purpose and that there is no need for fish full or partial life cycle tests for most plant protection product active substances. PMID:24799351

Wheeler, James R; Maynard, Samuel K; Crane, Mark

2014-08-01

382

Toxicity of copper-spiked sediments to Tubifex tubifex (Oligochaeta, Tubificidae): Comparison of the 28-day reproductive bioassay with an early-life-stage bioassay  

SciTech Connect

Two sediment bioassay methods using Tubifex tubifex (Mueller, 1774) as the test species were compared. The first was an adult reproduction test, the second an early-life-stage survival test. The duration of both bioassays is 28 d and the amount of work required was similar; they may be useful alternatives to each other in different circumstances (e.g., the early life stage bioassay could be carried out with smaller volumes of sediment). The two bioassays were performed simultaneously on copper-spiked sediments. Sediments from two freshwater and two terrestrial sites were used; five separate, nonsimultaneous experiments were performed, one for each sediment or soil and a further experiment with soil with a good supplement. In the adult bioassay, there were large differences in the production of cocoons, eggs, and young among the control treatments of the five experiments. There were also major differences in the NOEC and LOEC for copper between the tested substrates. The early life stage bioassay appears to be less sensitive to copper toxicity than the adult reproductive bioassay since NOECs and LOECs are higher for early survival than for the most sensitive endpoints of the adult bioassay in three experiments out of five.

Vecchi, M.; Pasteris, A.; Bonomi, G. (Univ. degli Studi di Bologna (Italy). Dipt. di Biologia Evoluzionistica Sperimentale); Reynoldson, T.B. (Environment Canada, Burlington, Ontario (Canada). National Water Research Inst.)

1999-06-01

383

Eight Nucleotide Substitutions Inhibit Splicing to HPV-16 3?-Splice Site SA3358 and Reduce the Efficiency by which HPV-16 Increases the Life Span of Primary Human Keratinocytes  

PubMed Central

The most commonly used 3?-splice site on the human papillomavirus type 16 (HPV-16) genome named SA3358 is used to produce HPV-16 early mRNAs encoding E4, E5, E6 and E7, and late mRNAs encoding L1 and L2. We have previously shown that SA3358 is suboptimal and is totally dependent on a downstream splicing enhancer containingmultiple potential ASF/SF2 binding sites. Here weshow that only one of the predicted ASF/SF2 sites accounts for the majority of the enhancer activity. We demonstrate that single nucleotide substitutions in this predicted ASF/SF2 site impair enhancer function and that this correlates with less efficient binding to ASF/SF2 in vitro. We provide evidence that HPV-16 mRNAs that arespliced to SA3358 interact with ASF/SF2 in living cells. In addition,mutational inactivation of the ASF/SF2 site weakened the enhancer at SA3358 in episomal forms of the HPV-16 genome, indicating that the enhancer is active in the context of the full HPV-16 genome.This resulted in induction of HPV-16 late gene expression as a result of competition from late splice site SA5639. Furthermore, inactivation of the ASF/SF2 site of the SA3358 splicing enhancer reduced the ability of E6- and E7-encoding HPV-16 plasmids to increase the life span of primary keratinocytes in vitro, demonstrating arequirement for an intact splicing enhancer of SA3358 forefficient production of the E6 and E7 mRNAs. These results link the strength of the HPV-16 SA3358 splicing enhancer to expression of E6 and E7 and to the pathogenic properties of HPV-16. PMID:24039800

Li, Xiaoze; Johansson, Cecilia; Cardoso Palacios, Carlos; Mossberg, Anki; Dhanjal, Soniya; Bergvall, Monika; Schwartz, Stefan

2013-01-01

384

89. Reproduction from glass plate negative (Modjeski and Masters office, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

89. Reproduction from glass plate negative (Modjeski and Masters office, Modjeski Collection, No. 6, not dated) DRAW SPAN - Burlington Northern Railroad Bridge, Spanning Willamette River at River Mile 6.9, Portland, Multnomah County, OR

385

95. Reproduction from glass plate negative (Modjeski and Masters office, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

95. Reproduction from glass plate negative (Modjeski and Masters office, Modjeski Collection, No. 150, January 18, 1908) SPANS 4 AND 5 - Burlington Northern Railroad Bridge, Spanning Willamette River at River Mile 6.9, Portland, Multnomah County, OR

386

98. Reproduction from glass plate negative (Modjeski and Masters office, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

98. Reproduction from glass plate negative (Modjeski and Masters office, Modjeski Collection, No. 181, May 5, 1908) STEEL ERECTION AT DRAW SPAN - Burlington Northern Railroad Bridge, Spanning Willamette River at River Mile 6.9, Portland, Multnomah County, OR

387

100. Reproduction from glass plate negative (Modjeski and Masters office, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

100. Reproduction from glass plate negative (Modjeski and Masters office, Modjeski Collection, No. 198, July 25, 1908) VIEW OF DRAW SPAN - Burlington Northern Railroad Bridge, Spanning Willamette River at River Mile 6.9, Portland, Multnomah County, OR

388

A woman's journey through the reproductive, transitional and postmenopausal periods of life: impact on cardiovascular and musculo-skeletal risk and the role of estrogen replacement.  

PubMed

Sex hormones are fundamental for female development and they are important physiologically to maintain the health and normal functioning of several organs such as the brain, heart and bone. It is now clear that the hormonal changes that occur during a woman's life, particularly her estrogen status, can modulate disease activity. This is especially true for cardiovascular and musculo-skeletal diseases, which are two leading causes of morbidity and mortality in women. With the general aging of the population they represent a serious and growing public health concern. Estrogen synthesis and blood levels fluctuate during a woman's life and in this review three broad periods will be considered: reproductive phase, transition and postmenopausal phase. Generally speaking, women in the reproductive phase of their life are at low risk of cardiovascular and musculo-skeletal disorders. However, the onset of menopause and the loss of ovarian function is associated with a significant increase in the prevalence of diseases such as coronary heart disease, osteoarthritis and osteoporosis. The prevalence of these debilitating diseases continues to increase through the postmenopausal period. Estrogen replacement is an obvious treatment approach to counter the problems associated with the loss of ovarian function and subsequent estrogen deficiency. Overall, oral and transdermal estrogen replacement are similarly effective in relieving menopausal symptoms and disorders that manifest during this period of a woman's life. Transdermal estrogen may be preferable in older women because of its lower thrombogenic potential. In this journey through a woman's life current best evidence relating to cardiovascular and musculo-skeletal risk will be reviewed in line with well documented management strategies. PMID:21788109

Stevenson, John C

2011-10-01

389

Community attitude towards the reproductive rights and sexual life of people living with HIV/AIDS in Olorunda Local Government Area, Osogbo, Nigeria  

PubMed Central

Background Globally, the Human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) epidemic remains a major public health problem. In most countries in sub-Saharan Africa, HIV/AIDS has already reversed the post-independence developmental gains. Purpose This study assessed community attitudes regarding the reproductive rights and sexual life of people living with HIV/AIDS (PLWHA) in Olorunda Local Government Area of Osun State, Southwestern Nigeria. Design and methods In a community-based descriptive cross-sectional study, the sample size calculation was based on the assumption that 67% of the target population has a negative attitude regarding the reproductive rights of PLWHA; a confidence interval (CI) of 95% was used. A minimum sample size of 340 was obtained using the formula n = Z2pq/d2. An anticipated 10% nonresponse rate was added to obtain a sample size of 374; a multistage sampling technique was utilized to select a total of 450 respondents. Data collected through a semistructured standardized and pretested questionnaire were analyzed using Statistical Package for Social Sciences software, version 15. Results The study revealed that 283 (66.6%) and 142 (33.4%) of respondents were urban and rural dwellers, respectively. Mean age of respondents was 28.7 years 2.2 years. Four hundred and two (94.6%) respondents were aware of HIV/AIDS, and 88.7% had knowledge of at least six different modes of HIV/AIDS transmission. About 30.7% of respondents had discriminatory and stigmatizing attitudes towards PLWHA, and 50.9% and 44.8% had negative attitudes towards their sexual and reproductive rights, respectively. There were significant associations between gender, marital status, educational status, occupation, and residential area of respondents and their attitude towards the reproductive and sexual right of PLWHA (P < 0.05). Conclusion and recommendation Discriminatory and stigmatizing attitudes to PLWHA found among respondents translated into a negative attitude regarding the reproductive and sexual rights of PLWHA. There is an urgent need to institute programs for raising community awareness about the rights of PLWHA, especially in rural areas, and to strengthen legislative provisions for protecting and preserving the reproductive rights of PLWHA. PMID:23807862

Asekun-Olarinmoye, EO; Asekun-Olarinmoye, IO; Adebimpe, WO; Olugbenga-Bello, AI

2013-01-01

390

An empirical test of evolutionary theories for reproductive senescence and reproductive effort  

E-print Network

An empirical test of evolutionary theories for reproductive senescence and reproductive effort that differential reproductive effort and rate of reproductive senescence will evolve under different rates of external mortality. We examine the evolutionary divergence of age-specific reproduction in two life

Bronikowski, Anne

391

An emerging interface between life science and nanotechnology: present status and prospects of reproductive healthcare aided by nano-biotechnology  

PubMed Central

Among the various applications of nano-biotechnology, healthcare is considered one of the most significant domains. For that possibility to synthesize various kind of nanoparticles (NPs) and the ever-increasing ability to control their size as well as structure, to improve surface characteristics and binding NPs with other desired curing agents has played an important role. In this paper, a brief sketch of various kinds of nanomaterials and their biomedical applications is given. Despite claims of bio-nanotechnology about to touch all areas of medical science, information pertaining to the role of nanotechnology for the betterment of reproductive healthcare is indeed limited. Therefore, the various achievements of nano-biotechnology for healthcare in general have been illustrated while giving special insight into the role of nano-biotechnology for the future of reproductive healthcare betterment as well as current achievements of nanoscience and nanotechnology in this arena. PMID:24600516

Jha, Rakhi K.; Jha, Pradeep K.; Chaudhury, Koel; Rana, Suresh V.S.; Guha, Sujoy K.

2014-01-01

392

Life is still going on: Reproductive intentions among HIV-positive women and men in South Africa  

Microsoft Academic Search

This article reports on qualitative research investigating HIV positive individuals reproductive intentions and their influencing factors in Cape Town, South Africa.In-depth interviews were held with 61 HIV positive women and men; at the time of interview, half had been receiving antiretroviral treatment (ART) for over 6 months and half were not receiving ART.Being HIV positive modified but did not remove

Diane Cooper; Jane Harries; Landon Myer; Phyllis Orner; Hillary Bracken

2007-01-01

393

An empirical test of evolutionary theories for reproductive senescence and reproductive effort in the garter snake Thamnophis elegans  

Microsoft Academic Search

Evolutionary theory predicts that differential reproductive effort and rate of reproductive senescence will evolve under different rates of external mortality. We examine the evolutionary divergence of age-specific reproduction in two life-history ecotypes of the western terrestrial garter snake, Thamnophis elegans. We test for the signature of reproductive senescence (decreasing fecundity with age) and increasing reproductive effort with age (increasing reproductive

Amanda M. Sparkman; Stevan J. Arnold; Anne M. Bronikowski

2007-01-01

394

Changes in reproductive life-history strategies in response to nest density in a shell-brooding cichlid, Telmatochromis vittatus  

NASA Astrophysics Data System (ADS)

To determine whether the appearance of a reproductively parasitic tactic varies, and how this variation affects territorial males of the Lake Tanganyika cichlid fish Telmatochromis vittatus, we examined the reproductive ecology of territorial males in Mtondwe and compared it with that of a neighboring Wonzye population, where nest density differs from that at Mtondwe. In Wonzye, with high nest density, male tactics change with their body size from a territorial to a non-territorial parasitic tactic called piracy in which they conquer several nests defended by territorial males and take over the nests while females are spawning. These "pirate" males could decrease the costs incurred by travelling among nests by exclusively targeting aggregations of nests in close proximity while avoiding separate nests. Territorial males in Wonzye sacrifice the potential higher attractiveness offered by large nests and instead compete for nests farther from neighbors on which pirates less frequently intrude. In contrast, the Mtondwe population had lower nest density and piracy was absent. Given that the success of piracy depends on the close proximity of nests, nest density is likely responsible for the observed variation in the occurrence of piracy between the two populations. Furthermore, in Mtondwe, territorial males competed for larger nests and were smaller than the territorial males in Wonzye. Thus, this lower nest density may free territorial males from the selection pressures for increased size caused by both defense against nest piracy and the need to develop into pirates as they grow.

Ota, Kazutaka; Hori, Michio; Kohda, Masanori

2012-01-01

395

Changes in reproductive life-history strategies in response to nest density in a shell-brooding cichlid, Telmatochromis vittatus.  

PubMed

To determine whether the appearance of a reproductively parasitic tactic varies, and how this variation affects territorial males of the Lake Tanganyika cichlid fish Telmatochromis vittatus, we examined the reproductive ecology of territorial males in Mtondwe and compared it with that of a neighboring Wonzye population, where nest density differs from that at Mtondwe. In Wonzye, with high nest density, male tactics change with their body size from a territorial to a non-territorial parasitic tactic called piracy in which they conquer several nests defended by territorial males and take over the nests while females are spawning. These "pirate" males could decrease the costs incurred by travelling among nests by exclusively targeting aggregations of nests in close proximity while avoiding separate nests. Territorial males in Wonzye sacrifice the potential higher attractiveness offered by large nests and instead compete for nests farther from neighbors on which pirates less frequently intrude. In contrast, the Mtondwe population had lower nest density and piracy was absent. Given that the success of piracy depends on the close proximity of nests, nest density is likely responsible for the observed variation in the occurrence of piracy between the two populations. Furthermore, in Mtondwe, territorial males competed for larger nests and were smaller than the territorial males in Wonzye. Thus, this lower nest density may free territorial males from the selection pressures for increased size caused by both defense against nest piracy and the need to develop into pirates as they grow. PMID:22089034

Ota, Kazutaka; Hori, Michio; Kohda, Masanori

2012-01-01

396

Sentencing Juveniles to Life in Prison: The Reproduction of Juvenile Justice for Young Adolescents Charged with Murder  

ERIC Educational Resources Information Center

In "Roper v. Simmons," the U.S. Supreme Court determined that the sentencing of juveniles to death violated the constitutional amendment against cruel and unusual punishment. Similarly, the Court most recently decided that life without parole for non-homicide offenses is also unconstitutional ("Graham v. Florida," 2010). Part of the reason for the

Singer, Simon I.

2011-01-01

397

Sentencing Juveniles to Life in Prison: The Reproduction of Juvenile Justice for Young Adolescents Charged With Murder  

Microsoft Academic Search

In Roper v. Simmons, the U.S. Supreme Court determined that the sentencing of juveniles to death violated the constitutional amendment against cruel and unusual punishment. Similarly, the Court most recently decided that life without parole for nonhomicide offenses is also unconstitutional (Graham v. Florida, 2010). Part of the reason for the Courts decisions is the lack of consensus as to

Simon I. Singer

2011-01-01

398

Life cycle of the multiarmed sea star Coscinasterias acutispina (Stimpson, 1862) in laboratory culture: sexual and asexual reproductive pathways.  

PubMed

The multiarmed sea star Coscinasterias acutispina generally has 7-10 arms and 2-5 madreporites. It is known to be able to reproduce by asexual fission, and we have previously observed that this species also has the ability to reproduce sexually; however, there has been no report until now of spawning in this species. We succeeded in establishing a long-term culture of juveniles produced by artificial fertilization. Twelve months after the completion of metamorphosis, three individuals had six arms of the same length and a madreporite. At this time, fission occurred in two of these individuals, while the remaining individual underwent fission four months later. Each sea star divided into two halves, provided with three arms each. Thereafter, four or five new arms and two or four madreporites were formed anew in each of the six daughter sea-stars, so that by 30 days after the first fission the number of arms and madreporites in each was similar to that in adults. A second fission occurred in four of these six individuals, four or five months after the first fission, and in three of them the plane of division was the same as that of the first fission. The original three individuals eventually proliferated to 12 by undergoing fission. All individuals had fully developed gonads by 1-3 months after the second fission. Some of them eventually spawned under laboratory culture, and the resulting larvae metamorphosed into juveniles. Our observations demonstrate that individuals of C. acutispina possess the potential for both sexual and asexual reproduction. PMID:21557653

Shibata, Daisuke; Hirano, Yoshiaki; Komatsu, Miko

2011-05-01

399

Allometric constraints and variables of reproductive effort in brachyuran crabs  

Microsoft Academic Search

Allometric relationships of reproductive output were compared in 20 species from 7 families of brachyuran crabs from the east and west coasts of North America, using regression analysis of log reproductive parameters versus log body weight. Comparisons of crabs spanning 4 orders of magnitude in body weight indicated that female body size was the principal determinant of reproductive output: 95%

A. H. Hines; Chesapeake Bay

1982-01-01

400

The politics of reproduction.  

PubMed

The topic of human reproduction encompasses events throughout the human and especially female life-cycle as well as ideas and practices surrounding fertility, birth, and child care. Most of the scholarship on the subject, up through the 1960s, was based on cross-cultural surveys focused on the beliefs, norms, and values surrounding reproductive behaviors. Multiple methodologies and subspecialties, and fields like social history, human biology, and demography were utilized for the analysis. The concept of the politics of reproduction synthesizes local and global perspectives. The themes investigated include: the concept of reproduction, population control, and the internationalization of state and market interests (new reproductive technologies); social movements and contested domains; medicalization and its discontents; fertility and its control; adolescence and teen pregnancy; birth; birth attendants; the construction of infancy and the politics of child survival; rethinking the demographic transition; networks of nurturance; and meanings of menopause. The medicalization of reproduction is a central issue of studies of birth, midwifery, infertility, and reproductive technologies. Scholars have also analyzed different parts of the female life-cycle as medical problems. Other issues worth analysis include the internationalization of adoption and child care workers; the crisis of infertility of low-income and minority women who are not candidates for expensive reproductive technologies; the concerns of women at high risk for HIV whose cultural status depends on their fertility; questions of reproduction concerning, lesbians and gay men (artificial insemination and discrimination in child rearing); the study of menopause; and fatherhood. New discourse analysis is used to analyze state eugenic policies; conflicts over Western neocolonial influences in which women's status as childbearers represent nationalist interests; fundamentalist attacks on abortion rights; and the AIDS crisis. PMID:12288961

Ginsburg, F; Rapp, R

1991-01-01

401

Exploring the Dimensionality of Digit Span  

ERIC Educational Resources Information Center

The Digit Span subtest from the Wechsler Scales is used to measure Freedom from Distractibility or Working Memory. Some published research suggests that Digit Span forward should be interpreted differently from Digit Span backward. The present study explored the dimensionality of the Wechsler Memory Scale-III Digit Span (forward and backward)

Bowden, Stephen C.; Petrauskas, Vilija M.; Bardenhagen, Fiona J.; Meade, Catherine E.; Simpson, Leonie C.

2013-01-01

402

Reproductive Hazards  

MedlinePLUS

... and female reproductive systems play a role in pregnancy. Problems with these systems can affect fertility and ... a reproductive hazard can cause different effects during pregnancy, depending on when she is exposed. During the ...

403

Animal Reproduction  

NSDL National Science Digital Library

From Dr. Michael Gregory of Clinton Community College, this site is a concise overview of animal reproduction. The site addresses important aspects of sexual and asexual reproduction, the male and female reproductive systems, fertilization, and the importance of hormones. Visitors to the site will find diagrams outlining biological processes especially helpful.

Gregory, Michael

2007-12-14

404

Genetics of host plant use and life history in the comma butterfly across Europe: varying modes of inheritance as a potential reproductive barrier.  

PubMed

Comma butterflies (Nymphalidae: Polygonia c-album L.) from one Belgian site and three Spanish sites were crossed with butterflies from a Swedish population in order to investigate inheritance of female host plant choice, egg mass and larval growth rate. We found three different modes of inheritance for the three investigated traits. In line with earlier results from crosses between Swedish and English populations, the results regarding female oviposition preference (choice between Urtica dioica and Salix caprea) showed X-linked inheritance to be of importance for the variation between Sweden and the other sites. Egg mass and growth rate did not show any sex-linked inheritance. Egg mass differences between populations seem to be controlled mainly by additive autosomal genes, as hybrids showed intermediate values. The growth rates of both hybrid types following reciprocal crossings were similar to each other but consistently higher than for the two source populations, suggesting a nonadditive mode of inheritance which is not sex-linked. The different modes of inheritance for host plant preference vs. important life history traits are likely to result in hybrids with unfit combinations of traits. This type of potential reproductive barrier based on multiple ecologically important traits deserves more attention, as it should be a common situation for instance in the early stages of population divergence in host plant usage, facilitating ecological speciation. PMID:17040385

Nygren, G H; Nylin, S; Stefanescu, C

2006-11-01

405

2.MD Hand Span Measures  

NSDL National Science Digital Library

This is a task from the Illustrative Mathematics website that is one part of a complete illustration of the standard to which it is aligned. Each task has at least one solution and some commentary that addresses important asects of the task and its potential use. Here are the first few lines of the commentary for this task: Hand span is a measure of distance from the tip of the thumb to the tip of the little finger with the hand fully extended. Each student places his or h...

406

Mammalian reproductive strategies : genes, photoperiod and latitude  

E-print Network

Mammalian reproductive strategies : genes, photoperiod and latitude F. H. BRONSON Institute of Reproductive Bio%gy Zoo%gy Department, University of Texas, Austin, Texas 78712 USA. Summary. This paper's reproduction. The factors most important in making this decision would seem to be the following : life

Paris-Sud XI, Université de

407

Date of eclosion modulates longevity: insights across dietary-restriction gradients and female reproduction in the mexfly Anastrepha ludens  

PubMed Central

We use unique experimental data on daily reproduction and survival of individual fruit flies from eight cohorts eclosed at different dates in 2004 and 2005 who were treated with varying proportions of sugar and yeast and subject to different caloric restrictions (CR). We investigate the relationship between eclosion date and longevity across diets and reproduction in Anastrepha ludens. We show that eclosion date can be associated with uncontrolled external or internal factor(s) which can modulate longevity of males and females independently of diet and reproduction to the extent similar to the effect of diet on longevity. The effect of diet manipulation on longevity is sensitive to date of eclosion with the role of CR in life extension ranging from beneficial to harmful. Interaction of date of eclosion with compositional changes of sugar and yeast but not with CR is responsible for life extension. Highly protein-enriched diets reliably maximize reproduction but not life span. Decreased longevity of flies treated with high-protein diets may be associated with harmful consequences of protein ingestion but is unlikely a result of high reproduction rates. We present evidence for the presence of two frailty-sensitive weakly interacting mechanisms of longevity in female flies associated with differences in predisposed fitness. PMID:19716408

Kulminski, Alexander M.; Molleman, Freerk; Culminskaya, Irina V.; Arbeev, Konstantin G.; Ukraintseva, Svetlana V.; Carey, James R.; Yashin, Anatoli I.

2009-01-01

408

Octave-spanning semiconductor laser  

E-print Network

We present here a semiconductor injection laser operating in continuous wave with an emission covering more than one octave in frequency, and displaying homogeneous power distribution among the lasing modes. The gain medium is based on a heterogeneous quantum cascade structure operating in the THz range. Laser emission in continuous wave takes place from 1.64 THz to 3.35 THz with optical powers in the mW range and more than 80 modes above threshold. Free-running beatnote investigations on narrow waveguides with linewidths of 980 Hz limited by jitter indicate frequency comb operation on a spectral bandwidth as wide as 624 GHz, making such devices ideal candidates for octave-spanning semiconductor-laser-based THz frequency combs.

Rsch, Markus; Beck, Mattias; Faist, Jrme

2014-01-01

409

C-SPAN: The Communicators  

NSDL National Science Digital Library

C-SPAN has given viewers programs like the celebrated "BookTV" and "Booknotes" and now they have come out with "The Communicators". This program features a half-hour interview with "the people who shape our digital future." Interviews include the acting chairman of the Federal Communications Commission (FCC), Fred Humphries of Microsoft Corporation's Federal Affairs division, and legislators concerned with such matters. At the top of the site's homepage, visitors will find the latest interview in the series, complete with additional relevant web resources. Further down the homepage, visitors will find a link to their podcasts, along with a complete listing of "Recent Events". The site is rounded out by a detailed set of "Web Resources" related to the federal government, which can be found on the right-hand side of the page.

410

Unisexual reproduction.  

PubMed

Sexual reproduction is ubiquitous throughout the eukaryotic kingdom, but the capacity of pathogenic fungi to undergo sexual reproduction has been a matter of intense debate. Pathogenic fungi maintained a complement of conserved meiotic genes but the populations appeared to be clonally derived. This debate was resolved first with the discovery of an extant sexual cycle and then unisexual reproduction. Unisexual reproduction is a distinct form of homothallism that dispenses with the requirement for an opposite mating type. Pathogenic and nonpathogenic fungi previously thought to be asexual are able to undergo robust unisexual reproduction. We review here recent advances in our understanding of the genetic and molecular basis of unisexual reproduction throughout fungi and the impact of unisex on the ecology and genomic evolution of fungal species. PMID:24880737

Roach, Kevin C; Feretzaki, Marianna; Sun, Sheng; Heitman, Joseph

2014-01-01

411

C-SPAN Networks: Professors' Guide.  

ERIC Educational Resources Information Center

The intention of this guide is to serve as a forum for college faculty members to share ideas and articles about using C-SPAN programming in college classrooms and in academic research. The first article, "C-SPAN as a 'Lecture Launcher'" (Stephen Frantzich) illustrates how well-chosen segments of C-SPAN programming can be used to stimulate

C-SPAN in the Classroom, 1993

1993-01-01

412

Life  

NSDL National Science Digital Library

Run the classic game of life, learning about probabilities, chaos and simulation. This activity allows the user to run a randomly generated world or test out various patterns. This is a very powerful activity with a wide range of options. It runs in a separate window.

413

Temporal variability in the life history and reproductive biology of female dugongs in Torres Strait: The likely role of sea grass dieback  

NASA Astrophysics Data System (ADS)

The extensive sea grass meadows in Torres Strait enable it to be a globally important habitat for the dugong, Dugong dugon, a marine mammal of cultural and dietary significance to Torres Strait Islanders and the basis for the substantial island-based fishery in the Torres Strait Protected Zone. Torres Strait sea grass communities are subjected to episodic diebacks which are now believed to be largely natural events. Information on dugong life history was obtained from specimens obtained from female dugongs as they were butchered for food by Indigenous hunters at two major dugong hunting communities in Torres Strait: Daru (9.04S, 143.21E) in 1978-1982 (a time of sea grass dieback and recovery) and Mabuiag Island (9.95S, 142.15E) in 1997-1999 (when sea grasses were abundant). Dugongs sampled in 1997-1999 had their first calf at younger ages (minimum of 6 cf. 10 years), and more frequently (interbirth interval based on all possible pregnancies 2.60.4 (S.E.) yr cf. 5.81.0 yr) than the dugongs sampled in 1978-1982. Pregnancy rates increased monotonically during 1978-1982, coincident with sea grass recovery. The age distribution of the female dugongs collected in 1997-1999 also suggested a low birth rate between 1973 and 1983 and/or or a high level of mortality for animals born during this period. These results add to the evidence from other regions that the life history and reproductive rate of female dugongs are adversely affected by sea grass loss, the effect of which cannot be separated from a possible density-dependent response to changes in dugong population size. Many green turtles in Torres Strait were also in poor body condition coincident with the 1970s sea grass dieback. The impacts of future sea grass diebacks need to be anticipated when management options for the traditional Torres Strait fisheries for dugongs and green turtles are evaluated.

Marsh, Helene; Kwan, Donna

2008-09-01

414

Effects of reproduction on immuno-suppression and oxidative damage, and hence support or otherwise for their roles as mechanisms underpinning life history trade-offs, are tissue and assay dependent.  

PubMed

Life history parameters appear to be traded off against each other, but the physiological mechanisms involved remain unclear. One hypothesis is that potentially energetically costly processes such as immune function and protection from oxidative stress may be compromised during reproductive attempts because of selective resource allocation. Lower temperatures also impose energy costs, and hence allocation decisions might be more pronounced when animals are forced to reproduce in the cold. Here, we experimentally tested whether reproduction at different ambient temperatures was associated with elevated oxidative stress and suppressed immune function in Mongolian gerbils (Meriones unguiculatus). Using a variety of different markers for both immune function and oxidative stress, we found that some measures of immune function (serum bactericidal capacity and size of the thymus) were significantly suppressed, while some measures of oxidative protection [serum superoxide dismutase (SOD) activity and glutathione peroxidase (GPx) activity] were also reduced, and a marker of oxidative damage (protein carbonyls in serum) was increased in lactating compared with non-reproductive gerbils. These changes were in line with the selective resource allocation predictions. However, the phytohaemagglutinin response and serum total immunoglobulin (IgG) were not suppressed, and other markers of oxidative damage [malondialdehyde (MDA) (TBARS) and protein carbonyls in the liver] were actually lower in lactating compared with non-reproductive gerbils, consistent with increased levels of SOD activity and total antioxidant capacity in the liver. These latter changes were opposite of the expectations based on resource allocation. Furthermore, other measures of protection (GPx levels in the liver and protein thiols in both serum and liver) and damage [MDA (TBARS) in serum] were unrelated to reproductive status. Ambient temperature differences did not impact on these patterns. Collectively, our results indicated that the inferred effects of reproduction on immunosuppression and oxidative damage, and hence support or otherwise for particular physiological mechanisms that underpin life history trade-offs, are critically dependent on the exact markers and tissues used. This may be because during reproduction individuals selectively allocate protection to some key tissues, but sacrifice protection of others. PMID:23997195

Yang, Deng-Bao; Xu, Yan-Chao; Wang, De-Hua; Speakman, John R

2013-11-15

415

Social Rank, Stress, Fitness, and Life Expectancy in Wild Rabbits  

NASA Astrophysics Data System (ADS)

Wild rabbits of the two sexes have separate linear rank orders, which are established and maintained by intensive fights. The social rank of individuals strongly influence their fitness: males and females that gain a high social rank, at least at the outset of their second breeding season, have a much higher lifetime fitness than subordinate individuals. This is because of two separate factors: a much higher fecundity and annual reproductive success and a 50% longer reproductive life span. These results are in contrast to the view in evolutionary biology that current reproduction can be increased only at the expense of future survival and/or fecundity. These concepts entail higher physiological costs in high-ranking mammals, which is not supported by our data: In wild rabbits the physiological costs of social positions are caused predominantly by differential psychosocial stress responses that are much lower in high-ranking than in low-ranking individuals.

von Holst, Dietrich; Hutzelmeyer, Hans; Kaetzke, Paul; Khaschei, Martin; Schnheiter, Ronald

416

CDC - Immunization Works April 201span>4 - News - Vaccines  

Science.gov Websites

4-5, 201span>4, Sacramento, CA 201span>4 National Adult and Influenza Immunization Summit, May 12-15, 201span>4, Atlanta, GA 201span>4 Massachusetts Adult Immunization Conference, May 20, 201span>4,...

417

Variation in the reproductive rate of bats  

Microsoft Academic Search

In many respects, bats have relatively slow life histories. However, the reproductive rate of bats (i.e., the proportion of females that reproduce in any breeding season) has not been critically examined. We compiled data on the reproductive rates of bats to test predictions based on life-history theory. Among 257 samples from 103 species, re - productive rate varied considerably and

Robert M. R. Barclay; Joel Ulmer; Cameron J. A. MacKenzie; Megan S. Thompson; Leif Olson; Julianne McCool; Elvie Cropley; Graeme Poll

2004-01-01

418

Life table of Paederus fuscipes (Coleoptera: Staphylinidae).  

PubMed

The life history characteristics of the rove beetle Paederus fuscipes Curtis were studied under laboratory conditions using three field strains from Malaysia: Desa Wawasan (DW), Sri Pinang (SP), and Ampang Jajar (AJ). The total development time of immature stages differed significantly among the three strains, especially between DW (17.43 +/- 0.16 d), SP (18.60 +/- 0.19 d), and AJ (18.68 +/- 0.22 d). Adult females and males from DW also exhibited a shorter life span, although the difference among strains was not significant. In terms of fecundity, the numbers of eggs laid per female for DW, SP, and AJ were 121.28 +/- 15.98, 127.30 +/- 18.01, and 147.45 +/- 17.12, respectively. Additionally, because of the shorter life span in DW strain, two apparent peaks in age-stage specific fecundity were detected. The beetles compensated for their shorter life span by increasing their reproductive activity to sustain the progeny in the population. The intrinsic rates of increase (r) of P. fuscipes from DW, SP, and AJ were 0.0773 +/- 0.0046 d(-1), 0.0788 +/- 0.0051 d(-1), and 0.0873 +/- 0.0054 d(-1), respectively; and the net reproduction rates (R0) were 40.09 +/- 7.39 offspring, 45.29 +/- 8.74 offspring, and 42.34 +/- 8.25 offspring, respectively. The mean generation time of P. fuscipes from AJ was 43.08 +/- 1.07 d, which was significantly higher than that from DW (47.95 +/- 1.36 d) and SP (48.57 +/- 1.43 d). The total immature development time of P. fuscipes in this study was shorter than values reported in previous studies. PMID:22679850

Bong, Lee-Jin; Neoh, Kok-Boon; Jaal, Zairi; Lee, Chow-Yang

2012-05-01

419

Extended attention span training system  

NASA Technical Reports Server (NTRS)

Attention Deficit Disorder (ADD) is a behavioral disorder characterized by the inability to sustain attention long enough to perform activities such as schoolwork or organized play. Treatments for this disorder include medication and brainwave biofeedback training. Brainwave biofeedback training systems feed back information to the trainee showing him how well he is producing the brainwave pattern that indicates attention. The Extended Attention Span Training (EAST) system takes the concept a step further by making a video game more difficult as the player's brainwaves indicate that attention is waning. The trainee can succeed at the game only by maintaining an adequate level of attention. The EAST system is a modification of a biocybernetic system that is currently being used to assess the extent to which automated flight management systems maintain pilot engagement. This biocybernetic system is a product of a program aimed at developing methods to evaluate automated flight deck designs for compatibility with human capabilities. The EAST technology can make a contribution in the fields of medical neuropsychology and neurology, where the emphasis is on cautious, conservative treatment of youngsters with attention disorders.

Pope, Alan T.; Bogart, Edward H.

1991-01-01

420

92. Reproduction from glass plate negative (Modjeski and Masters office, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

92. Reproduction from glass plate negative (Modjeski and Masters office, Modjeski Collection No. 70, December 24, 1906) CAISSON No. 2 - Burlington Northern Railroad Bridge, Spanning Willamette River at River Mile 6.9, Portland, Multnomah County, OR

421

96. Reproduction from glass plate negative (Modjeski and Masters office, ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

96. Reproduction from glass plate negative (Modjeski and Masters office, Modjeski Collection, No. 161, March 2, 1908) DERRICK AT PIER 2 - Burlington Northern Railroad Bridge, Spanning Willamette River at River Mile 6.9, Portland, Multnomah County, OR