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Sample records for activity declined sharply

  1. Reproduction and microhabitat selection in a sharply declining Northern Bobwhite population

    USGS Publications Warehouse

    Collins, B.M.; Williams, C.K.; Castelli, Paul M.

    2009-01-01

    Northern Bobwhite (Colinus virginianus) populations have been declining throughout their range, but some of the sharpest declines have been documented in the Mid-Atlantic states. We conducted a 2 year (2006-2007) breeding season (1 May-30 Sep) telemetry study in southern New Jersey to collect baseline data on Northern Bobwhite reproductive rates, and nest and brood microhabitat selection. We located 23 Northern Bobwhite nests, of which 21 were usable for survival analyses. Incubation-period nest survival rate was 0.454 ?? 0.010 (95 CI =0.2800.727). Mean clutch size was 14.2 ?? 0.58 (range 10-19, n = 20) and hatching success was 96.1 ?? 2.0 (range 86-100%, n = 10). The estimated probability that an individual that entered the breeding season would initiate incubation of ???1 nest was 0.687 for females and 0.202 for males. Nest microhabitat selection was positively related to visual obstruction and percentage of litter. Brood microhabitat selection was positively related to visual obstruction, vegetation height, and percentage of forbs but negatively related to percentage of cool season grass and litter. Fecundity metrics for Northern Bobwhites in southern New Jersey appear similar to those reported elsewhere in the species' range. Conservation efforts to increase Northern Bobwhite reproductive success in southern New Jersey should focus on increasing the quantity of available breeding habitat. ?? 2009 by the Wilson Ornithological Society.

  2. [Effect of the sharply strengthened motor activity on heart pumping ability of rats and mechanisms of its regulation].

    PubMed

    Nikitin, A S; Abzalov, R A; Abzalov, N I; Vafina, E Z

    2013-08-01

    The indicators of heart pumping ability of rats at a muscular loading of the maximum power and also in the conditions of transition from sharply strengthened motor activity regime on a strengthened motor activity regime at adrenergic influence stimulation and blockade were investigated. At rats of 100-daily age at the strengthened motor activity heart rate is less, and blood stroke volume is more, than in the rats, subject to muscular loading of the maximum power. The adrenergic influence on the heart's pumping ability of sharply strengthened motor activity rats is much more, than of unlimited motor activity rats. At the α1-adrenoreceptors blockade at 100-daily rats the decreasing in intensity of muscular loading causes increased in adrenergic influence on heart pumping ability.

  3. Cost leveling continues; planned activity drops sharply in US gas pipeline cnstruction

    SciTech Connect

    Morgan, J.M.

    1986-02-01

    Natural gas pipeline construction costs, as measured by the OGJ-Morgan Pipeline cost index for US gas-pipeline construction, barely crept up in the second quarter 1985. Construction activity for lines and compressor stations was down.

  4. Effect of sharply lowered muscular activity on the thyroid gland of the white rat

    NASA Technical Reports Server (NTRS)

    Bekishev, K.

    1980-01-01

    The effect of hypokinesia on the thyroid gland of 200 white rats was studied. The rats were kept in 16x6x6 cm cages for 90 days. The functional activity of the thyroids increased after 24 hrs of partial immobilization and peaked after 15 days. After 30 days of immobilization, the functional activity returned to normal in one third of the test animals and after 60 days in all animals. After 15 days of immobilization, the test animals began to lose weight (in comparison to the controls) and remained underweight for the rest of the test period (up to 90 days). When returned to normal conditions, they caught up with and even overtook in weight the control animals after about 1 month. All changes produced by hypokinesia were reversible after 1 month.

  5. A mitochondria-targeting artemisinin derivative with sharply increased antitumor but depressed anti-yeast and anti-malaria activities

    PubMed Central

    Sun, Chen; Cao, Yu; Zhu, Pan; Zhou, Bing

    2017-01-01

    The potent anti-malarial drug artemisinins are additionally anti-tumorigenic and inhibitory to yeast growth. The action mechanism of artemisinins, however, is not well understood. Heme and mitochondrial membrane are both suggested to be involved in the action of artemisinins. Because heme is also synthesized in the mitochondrion, mitochondria appear to be a critical organelle for artemisinins’ activities. In this study, we synthesized a mitochondria-targeting artemisinin derivative by conjugating triphenylphosphonium (TPP) to artelinic acid (ARTa). ARTa-TPP displays far more potent anti-tumorigenic activity than its parent compound. In contrast, ARTa-TPP is much less active against yeast respiration growth and malarial parasites. Notably, ARTa-TPP is also associated with increased toxicity to other kinds of control mammalian cells. These results suggest divergent action modes for artemisinins against cancer cells and malaria or yeast cells. We conclude that mitochondrial targeting could substantially elevate the anticancer potency of artemisinins, but the accompanied increased toxicity to normal cells raises an alert. The mechanism regarding the opposing effects of TPP conjugation to ARTa on its anticancer and anti-malarial/anti-yeast potencies is discussed based on our current understandings of artemisinins’ action. PMID:28368011

  6. A mitochondria-targeting artemisinin derivative with sharply increased antitumor but depressed anti-yeast and anti-malaria activities.

    PubMed

    Sun, Chen; Cao, Yu; Zhu, Pan; Zhou, Bing

    2017-04-03

    The potent anti-malarial drug artemisinins are additionally anti-tumorigenic and inhibitory to yeast growth. The action mechanism of artemisinins, however, is not well understood. Heme and mitochondrial membrane are both suggested to be involved in the action of artemisinins. Because heme is also synthesized in the mitochondrion, mitochondria appear to be a critical organelle for artemisinins' activities. In this study, we synthesized a mitochondria-targeting artemisinin derivative by conjugating triphenylphosphonium (TPP) to artelinic acid (ARTa). ARTa-TPP displays far more potent anti-tumorigenic activity than its parent compound. In contrast, ARTa-TPP is much less active against yeast respiration growth and malarial parasites. Notably, ARTa-TPP is also associated with increased toxicity to other kinds of control mammalian cells. These results suggest divergent action modes for artemisinins against cancer cells and malaria or yeast cells. We conclude that mitochondrial targeting could substantially elevate the anticancer potency of artemisinins, but the accompanied increased toxicity to normal cells raises an alert. The mechanism regarding the opposing effects of TPP conjugation to ARTa on its anticancer and anti-malarial/anti-yeast potencies is discussed based on our current understandings of artemisinins' action.

  7. U. S. plastics demand drops sharply

    SciTech Connect

    Not Available

    1980-07-28

    According to the Society of the Plastics Industry, plastics demand dropped sharply in the U.S. during second-quarter 1980. U.S. exports of themoplastics are down slightly from year-ago levels, and PVC and low-density polyethylene (LDPE) exports are increasing strongly, but strong exports can not offset a weak domestic market. The weakness in domestic PVC sales is due mostly to large drops in contruction pipe (-49%) and automotive uses, its leading markets, in the last year. LDPE sales have dropped 3% over the year, and 8% in film, LPDE's largest market. Polypropylene's two largest U.S. markets, molding and fibers, have also dropped sharply. Epoxy resin showed a May 1979 to May 1980 gain of 28% in exports, but three other thermosets, polyesters, urea-melamine, and phenolics, have dropped sharply since May 1979.

  8. The argon-induced decline in nitrogenase activity commences before the beginning of a decline in nodule oxygen uptake.

    PubMed

    Fischinger, Stephanie A; Schulze, Joachim

    2010-09-01

    Replacement of N(2) by argon in the air around nodules directs nitrogenase electron flow in its total onto H(+) resulting in increased nodule H(2) evolution (total nitrogenase activity (TNA)). However, argon application induces a so-called argon-induced decline in nitrogenase activity (Ar-ID) connected with decreased nodule oxygen permeability. Consequently, TNA measurements tend to underestimate total nitrogenase activity. It is unclear whether the decline in oxygen diffusion into nodules induces the Ar-ID, or whether a decline in nitrogenase activity is followed by lower nodule O(2) uptake. The objective of the present work was to examine the time sequence of the decline in nodule H(2) evolution and O(2) uptake after argon application. In addition, the reliability of TNA values, taken as quickly as possible after the switch to Ar/O(2), was tested through comparative measurement of (15)N(2) uptake of the same plants. Short-term TNA measurements in an optimized gas exchange measurement system yielded reliable results, verified by parallel determination of (15)N(2) uptake. A five min application of Ar/O(2) was without effect on the subsequent H(2) evolution in ambient air. A parallel experiment on control plants revealed that a decrease in nodule oxygen uptake began several minutes after the onset of the decline in H(2) evolution. We conclude that the primary effect of the replacement of N(2) by argon differs from oxygen diffusion control. A gas exchange system allowing an immediate taking of TNA yields reliable results and does not disturb nodule activity. Gas exchange measurements provide a powerful tool for studying nodule physiology and should be combined with material from molecular studies.

  9. Changes in physical activity and cognitive decline in older adults living in the community.

    PubMed

    Lee, Yunhwan; Kim, Jinhee; Han, Eun Sook; Chae, Songi; Ryu, Mikyung; Ahn, Kwang Ho; Park, Eun Ju

    2015-01-01

    Accumulating evidence suggests that physical activity may be beneficial in preserving cognition in late life. This study examined the association between baseline and changes in physical activity and cognitive decline in community-dwelling older people. Data were from the Korean Longitudinal Study of Aging, with 2605 aged 65 years and older subjects interviewed in 2006 and followed up for 2 years. Cognitive decline was defined by calculating the Reliable Change Index using the Mini-Mental State Examination. Physical activity levels were categorized as sedentary, low, or high. Changes in physical activity were classified as inactive, decreaser, increaser, or active. Logistic regression analysis of baseline and changes in physical activity with cognitive decline was performed. Compared with the sedentary group at baseline, both the low and high activity groups were less likely to experience cognitive decline. The active (odds ratio [OR] = 0.40, 95 % confidence interval [CI] 0.23-0.68) and increaser (OR = 0.45, 95 % CI 0.27-0.74) group, compared with the inactive counterpart, demonstrated a significantly lower likelihood of cognitive decline. Older adults who remained active or increased activity over time had a reduced risk of cognitive decline. Engagement in physical activity in late life may have cognitive health benefits.

  10. 26. Sharply angled view looking N at E wall of ...

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

    26. Sharply angled view looking N at E wall of N room of mill. - Hacienda Azurarera Santa Elena, Sugar Mill Ruins, 1.44 miles North of PR Route 2 Bridge Over Rio De La Plata, Toa Baja, Toa Baja Municipio, PR

  11. Hippocampal activation is associated with longitudinal amyloid accumulation and cognitive decline.

    PubMed

    Leal, Stephanie L; Landau, Susan M; Bell, Rachel K; Jagust, William J

    2017-02-08

    The amyloid hypothesis suggests that beta-amyloid (Aβ) deposition leads to alterations in neural function and ultimately to cognitive decline in Alzheimer's disease. However, factors that underlie Aβ deposition are incompletely understood. One proposed model suggests that synaptic activity leads to increased Aβ deposition. More specifically, hyperactivity in the hippocampus may be detrimental and could be one factor that drives Aβ deposition. To test this model, we examined the relationship between hippocampal activity during a memory task using fMRI and subsequent longitudinal change in Aβ using PIB-PET imaging in cognitively normal older adults. We found that greater hippocampal activation at baseline was associated with increased Aβ accumulation. Furthermore, increasing Aβ accumulation mediated the influence of hippocampal activation on declining memory performance, demonstrating a crucial role of Aβ in linking hippocampal activation and memory. These findings support a model linking increased hippocampal activation to subsequent Aβ deposition and cognitive decline.

  12. Trajectory of Declines in Physical Activity in Community-Dwelling Older Women: Social Cognitive Influences

    PubMed Central

    Hall, Katherine S.; Motl, Robert W.; White, Siobhan M.; Wójcicki, Thomas R.; Hu, Liang; Doerksen, Shawna E.

    2009-01-01

    Studies examining physical activity behavior suggest that activity levels decline with age. Such declines are particularly problematic among older adults in light of the research suggesting a protective effect of physical activity on numerous physical health outcomes associated with independent living. Despite a growing recognition of the importance of a physically active lifestyle, little is known about the role of demographic and psychosocial variables on this trajectory of change. In this study, the roles played by outcome expectations, self-efficacy, and functional limitations on changes in physical activity levels over a 2-year period in older women were assessed using latent growth curve modeling. Data were obtained from 249 community-dwelling older women (M age = 68.12, n = 81 Black, and n = 168 White). Demographic, health status, and psychosocial data were collected via self-report upon entry into the study. Self-reported physical activity was assessed at baseline and again at 12 and 24 months. As expected, physical activity declined over the 2-year period. Self-efficacy demonstrated an indirect association with the trajectory of decline in physical activity through functional limitations. Importantly, the pattern of relationships appears independent of demographic factors and chronic health conditions. PMID:19528360

  13. Trajectory of declines in physical activity in community-dwelling older women: social cognitive influences.

    PubMed

    McAuley, Edward; Hall, Katherine S; Motl, Robert W; White, Siobhan M; Wójcicki, Thomas R; Hu, Liang; Doerksen, Shawna E

    2009-09-01

    Studies examining physical activity behavior suggest that activity levels decline with age. Such declines are particularly problematic among older adults in light of the research suggesting a protective effect of physical activity on numerous physical health outcomes associated with independent living. Despite a growing recognition of the importance of a physically active lifestyle, little is known about the role of demographic and psychosocial variables on this trajectory of change. In this study, the roles played by outcome expectations, self-efficacy, and functional limitations on changes in physical activity levels over a 2-year period in older women were assessed using latent growth curve modeling. Data were obtained from 249 community-dwelling older women (M age = 68.12, n = 81 Black, and n = 168 White). Demographic, health status, and psychosocial data were collected via self-report upon entry into the study. Self-reported physical activity was assessed at baseline and again at 12 and 24 months. As expected, physical activity declined over the 2-year period. Self-efficacy demonstrated an indirect association with the trajectory of decline in physical activity through functional limitations. Importantly, the pattern of relationships appears independent of demographic factors and chronic health conditions.

  14. Coronal Dynamic Activities in the Declining Phase of a Solar Cycle

    NASA Astrophysics Data System (ADS)

    Jang, Minhwan; Woods, T. N.; Hong, Sunhak; Choe, G. S.

    2016-12-01

    It has been known that some solar activity indicators show a double-peak feature in their evolution through a solar cycle, which is not conspicuous in sunspot number. In this Letter, we investigate the high solar dynamic activity in the declining phase of the sunspot cycle by examining the evolution of polar and low-latitude coronal hole (CH) areas, splitting and merging events of CHs, and coronal mass ejections (CMEs) detected by SOHO/LASCO C3 in solar cycle 23. Although the total CH area is at its maximum near the sunspot minimum, in which polar CHs prevail, it shows a comparable second maximum in the declining phase of the cycle, in which low-latitude CHs are dominant. The events of CH splitting or merging, which are attributed to surface motions of magnetic fluxes, are also mostly populated in the declining phase of the cycle. The far-reaching C3 CMEs are also overpopulated in the declining phase of the cycle. From these results we suggest that solar dynamic activities due to the horizontal surface motions of magnetic fluxes extend far in the declining phase of the sunspot cycle.

  15. Age-Related Decline in Cardiorespiratory Fitness among Career Firefighters: Modification by Physical Activity and Adiposity.

    PubMed

    Baur, Dorothee M; Christophi, Costas A; Cook, E Francis; Kales, Stefanos N

    2012-01-01

    Firefighting is a very hazardous occupation, and strenuous fire duties require high levels of physical fitness. In the general adult population, cardiorespiratory fitness (CRF) declines with aging. We sought to investigate the effect of increasing age on CRF in male career firefighters as well as the modifying effects of physical activity and adiposity. We cross-sectionally examined 804 male career firefighters from two Midwestern states. CRF was determined from symptom-limited maximal treadmill exercise testing in metabolic equivalents (METS) following the Bruce protocol. Physical activity self-reports were extracted from responses to a health and lifestyle questionnaire. We found as expected that CRF declines with advancing age; however, the decline is greatly attenuated among leaner firefighters who report more physical activity. Furthermore, in a linear regression model including age, BMI, and variables describing physical activity behaviors, we could predict CRF (R(2) = 0.6286). The total weekly duration of aerobic exercise as well as the duration of weight lifting sessions both had significant impacts on age-related decline. We conclude that firefighters are more likely to maintain the high levels of CRF needed to safely perform their duties if they engage in frequent exercise and maintain healthy weights.

  16. Hippocampal activation is associated with longitudinal amyloid accumulation and cognitive decline

    PubMed Central

    Leal, Stephanie L; Landau, Susan M; Bell, Rachel K; Jagust, William J

    2017-01-01

    The amyloid hypothesis suggests that beta-amyloid (Aβ) deposition leads to alterations in neural function and ultimately to cognitive decline in Alzheimer’s disease. However, factors that underlie Aβ deposition are incompletely understood. One proposed model suggests that synaptic activity leads to increased Aβ deposition. More specifically, hyperactivity in the hippocampus may be detrimental and could be one factor that drives Aβ deposition. To test this model, we examined the relationship between hippocampal activity during a memory task using fMRI and subsequent longitudinal change in Aβ using PIB-PET imaging in cognitively normal older adults. We found that greater hippocampal activation at baseline was associated with increased Aβ accumulation. Furthermore, increasing Aβ accumulation mediated the influence of hippocampal activation on declining memory performance, demonstrating a crucial role of Aβ in linking hippocampal activation and memory. These findings support a model linking increased hippocampal activation to subsequent Aβ deposition and cognitive decline. DOI: http://dx.doi.org/10.7554/eLife.22978.001 PMID:28177283

  17. Telmisartan prevented cognitive decline partly due to PPAR-{gamma} activation

    SciTech Connect

    Mogi, Masaki; Li Jianmei; Tsukuda, Kana; Iwanami, Jun; Min, Li-Juan; Sakata, Akiko; Fujita, Teppei; Iwai, Masaru; Horiuchi, Masatsugu

    2008-10-24

    Telmisartan is a unique angiotensin receptor blocker (ARB) and partial agonist of peroxisome proliferator-activated receptor (PPAR)-{gamma}. Here, we investigated the preventive effect of telmisartan on cognitive decline in Alzheimer disease. In ddY mice, intracerebroventricular injection of A{beta} 1-40 significantly attenuated their cognitive function evaluated by shuttle avoidance test. Pretreatment with a non-hypotensive dose of telmisartan significantly inhibited such cognitive decline. Interestingly, co-treatment with GW9662, a PPAR-{gamma} antagonist, partially inhibited this improvement of cognitive decline. Another ARB, losartan, which has less PPAR-{gamma} agonistic effect, also inhibited A{beta}-injection-induced cognitive decline; however the effect was smaller than that of telmisartan and was not affected by GW9662. Immunohistochemical staining for A{beta} showed the reduced A{beta} deposition in telmisartan-treated mice. However, this reduction was not observed in mice co-administered GW9662. These findings suggest that ARB has a preventive effect on cognitive impairment in Alzheimer disease, and telmisartan, with PPAR-{gamma} activation, could exert a stronger effect.

  18. House Hearing on Climate Change Presents Sharply Different Views

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    2010-11-01

    With Republicans about to assume the majority and take over leadership positions in the U.S. House of Representatives when the next Congress convenes in January 2011, the House Committee on Science and Technology organized what may be the Democrats' last congressional hearing on climate change this session. Billed as “A Rational Discussion of Climate Change: The Science, the Evidence, the Response,” the 17 November hearing featured three panels of scientists focusing on the basic science of climate change and impacts of carbon dioxide (CO2) on temperature and ocean acidity. In addition to the scientific information presented by witnesses, there was much back and forth debate, sometimes testy, among panelists with sharply different perspectives. Comments from the House members ranged across the board, from trying to set a tone of objectivity to impassioned remarks.

  19. Risk of decline in functional activities in dementia with Lewy bodies and Alzheimer disease.

    PubMed

    Gill, Dawn P; Koepsell, Thomas D; Hubbard, Rebecca A; Kukull, Walter A

    2011-01-01

    We examined the risk of 1-year decline in 4 everyday activities in patients with dementia with Lewy bodies (DLB), relative to patients with Alzheimer disease (AD). Data were from the National Alzheimer's Coordinating Center, gathered from 32 Alzheimer's Disease Centers. Participants (n=1880) were: aged 60+ years, demented with a primary clinical diagnosis of probable AD or DLB, and had a global Clinical Dementia Rating of 0.5 to 2. The activities were measured with the Functional Activities Questionnaire. In modified Poisson regression models adjusted for demographics, baseline activity, years from symptom onset, cognitive impairment, and comorbidities; DLB participants aged 67 to 81 years had 1.5 to 2 times increased risk of decline in performing basic kitchen tasks, engaging in games/hobbies, and paying attention/understanding, relative to AD participants of the same age (P<0.05). There was no significant difference between AD and DLB participants beyond this age range. For decline in ability to go shopping alone, there was also no significant difference between AD and DLB participants. In summary, the functional course of DLB, relative to AD, may depend on the age of the patient. These findings may provide anticipatory guidance to families and healthcare providers, which may be useful in the planning of care strategies.

  20. Does a physically active lifestyle attenuate decline in all cognitive functions in old age?

    PubMed

    Ballesteros, Soledad; Mayas, Julia; Reales, Jose Manuel

    2013-07-01

    In this study, the performance of a group of 20 physically active older adults was compared with that of a group of 20 sedentary healthy older adults while performing a series of cognitive tasks. These tasks were designed to assess processes that deteriorate most with age, namely executive control (assessed with the Wisconsin Card Sorting Task) and processing speed (simple and choice reaction time tasks). A repetition priming task that does not decline with age, involving attended and unattended picture outlines at encoding, was also included as a control task. The results show that a physically active lifestyle has a positive influence on executive control, processing speed, and controlled processing. As expected, a physically active lifestyle did not enhance repetition priming for attended stimuli, nor did it produce priming for unattended stimuli at encoding. Both groups exhibited robust priming for attended stimuli and no priming for unattended ones. Executive control functions are of vital importance for independent living in old age. These results have practical implications for enhancing the cognitive processes that decline most in old age. Promoting a physically active lifestyle throughout adulthood could significantly reduce the decline of effortful executive control functions in old age.

  1. Role of physical activity in reducing cognitive decline in older Mexican-American adults.

    PubMed

    Ottenbacher, Allison J; Snih, Soham Al; Bindawas, Saad M; Markides, Kyriakos S; Graham, James E; Samper-Ternent, Rafael; Raji, Mukaila; Ottenbacher, Kenneth J

    2014-09-01

    The effect of physical activity on cognitive function in older adults from minority and disadvantaged populations is not well understood. This study examined the longitudinal association between physical activity and cognition in older Mexican Americans. The study methodology included a prospective cohort with longitudinal analysis of data from the Hispanic Established Populations for the Epidemiologic Study of the Elderly. General linear mixed models were used to assess the associations and interactions between physical activity and cognitive function over 14 years. Community-based assessments were performed in participants' homes. Physical activity was recorded for 1,669 older Mexican Americans using the Physical Activity Scale for the Elderly. Cognition was measured using the Mini-Mental State Examination (MMSE) and separated into memory and nonmemory components. A statistically significant positive association was observed between levels of physical activity and cognitive function after adjusting for age, sex, marital status, education, and comorbid health conditions. There was a statistically significant difference in MMSE scores over time between participants in the third (β = 0.11, standard error (SE) = 0.05) and fourth (β = 0.10, SE = 0.2) quartiles of physical activity and those in the first. The protective effect of physical activity on cognitive decline was evident for the memory component of the MMSE but not the nonmemory component after adjusting for covariates. Greater physical activity at baseline was associated with less cognitive decline over 14 years in older Mexican Americans. The reduction in cognitive decline appeared to be related to the memory components of cognitive function.

  2. NK cell activating receptor ligand expression in lymphangioleiomyomatosis is associated with lung function decline

    PubMed Central

    Osterburg, Andrew R.; Nelson, Rebecca L.; Yaniv, Benyamin Z.; Foot, Rachel; Donica, Walter R.F.; Nashu, Madison A.; Liu, Huan; Wikenheiser-Brokamp, Kathryn A.; Moss, Joel; McCormack, Francis X.; Borchers, Michael T.

    2016-01-01

    Lymphangioleiomyomatosis (LAM) is a rare lung disease of women that leads to progressive cyst formation and accelerated loss of pulmonary function. Neoplastic smooth muscle cells from an unknown source metastasize to the lung and drive destructive remodeling. Given the role of NK cells in immune surveillance, we postulated that NK cell activating receptors and their cognate ligands are involved in LAM pathogenesis. We found that ligands for the NKG2D activating receptor UL-16 binding protein 2 (ULBP2) and ULBP3 are localized in cystic LAM lesions and pulmonary nodules. We found elevated soluble serum ULBP2 (mean = 575 pg/ml ± 142) in 50 of 100 subjects and ULBP3 in 30 of 100 (mean = 8,300 pg/ml ± 1,515) subjects. LAM patients had fewer circulating NKG2D+ NK cells and decreased NKG2D surface expression. Lung function decline was associated with soluble NKG2D ligand (sNKG2DL) detection. The greatest rate of decline forced expiratory volume in 1 second (FEV1, –124 ± 30 ml/year) in the 48 months after enrollment (NHLBI LAM Registry) occurred in patients expressing both ULBP2 and ULBP3, whereas patients with undetectable sNKG2DL levels had the lowest rate of FEV1 decline (–32.7 ± 10 ml/year). These data suggest a role for NK cells, sNKG2DL, and the innate immune system in LAM pathogenesis. PMID:27734028

  3. Parenchyma cell respiration and survival in secondary xylem: does metabolic activity decline with cell age?

    PubMed

    Spicer, R; Holbrook, N M

    2007-08-01

    Sapwood respiration often declines towards the sapwood/heartwood boundary, but it is not known if parenchyma metabolic activity declines with cell age. We measured sapwood respiration in five temperate species (sapwood age range of 5-64 years) and expressed respiration on a live cell basis by quantifying living parenchyma. We found no effect of parenchyma age on respiration in two conifers (Pinus strobus, Tsuga canadensis), both of which had significant amounts of dead parenchyma in the sapwood. In angiosperms (Acer rubrum, Fraxinus americana, Quercus rubra), both bulk tissue and live cell respiration were reduced by about one-half in the oldest relative to the youngest sapwood, and all sapwood parenchyma remained alive. Conifers and angiosperms had similar bulk tissue respiration despite a smaller proportion of parenchyma in conifers (5% versus 15-25% in angiosperms), such that conifer parenchyma respired at rates about three times those of angiosperms. The fact that 5-year-old parenchyma cells respired at the same rate as 25-year-old cells in conifers suggests that there is no inherent or intrinsic decline in respiration as a result of cellular ageing. In contrast, it is not known whether differences observed in cellular respiration rates of angiosperms are a function of age per se, or whether active regulation of metabolic rate or positional effects (e.g. proximity to resources and/or hormones) could be the cause of reduced respiration in older sapwood.

  4. Declining physical capacity but maintained aerobic activity in early Alzheimer's disease.

    PubMed

    Cedervall, Ylva; Kilander, Lena; Aberg, Anna Cristina

    2012-05-01

    The longitudinal influences on physical capacity and habitual aerobic activity level in the early stages of Alzheimer's disease (AD) are unclear. Therefore, changes in physical capacity and aerobic activity level were evaluated. Twenty-five individuals with AD were assessed annually for 2 years, by 10-m walk test, 6-minute walk test, and timed up-and-go (TUG) single/dual tasks. Habitual aerobic activity was assessed by diary registrations. The AD group showed a lower physical capacity than controls at baseline but comparable levels of aerobic activity. During the follow-up period, physical capacity declined in the AD group, but the aerobic activity levels changed only marginally. Our results show that in the early stages of AD, people are capable of maintaining health-promoting aerobic activity levels, despite a decline in their physical capacity. Additionally, it appears that cognitive dysfunction contributes to an impaired physical capacity. The TUG tasks might, therefore, be useful for detecting early signs of cognitive impairment.

  5. Summer declines in activity and body temperature offer polar bears limited energy savings

    USGS Publications Warehouse

    Whiteman, J.P.; Harlow, H.J.; Durner, George M.; Anderson-Sprecher, R.; Albeke, Shannon E.; Regehr, Eric V.; Amstrup, Steven C.; Ben-David, M.

    2015-01-01

    Polar bears (Ursus maritimus) summer on the sea ice or, where it melts, on shore. Although the physiology of “ice” bears in summer is unknown, “shore” bears purportedly minimize energy losses by entering a hibernation-like state when deprived of food. Such a strategy could partially compensate for the loss of on-ice foraging opportunities caused by climate change. However, here we report gradual, moderate declines in activity and body temperature of both shore and ice bears in summer, resembling energy expenditures typical of fasting, nonhibernating mammals. Also, we found that to avoid unsustainable heat loss while swimming, bears employed unusual heterothermy of the body core. Thus, although well adapted to seasonal ice melt, polar bears appear susceptible to deleterious declines in body condition during the lengthening period of summer food deprivation.

  6. Animal physiology. Summer declines in activity and body temperature offer polar bears limited energy savings.

    PubMed

    Whiteman, J P; Harlow, H J; Durner, G M; Anderson-Sprecher, R; Albeke, S E; Regehr, E V; Amstrup, S C; Ben-David, M

    2015-07-17

    Polar bears (Ursus maritimus) summer on the sea ice or, where it melts, on shore. Although the physiology of "ice" bears in summer is unknown, "shore" bears purportedly minimize energy losses by entering a hibernation-like state when deprived of food. Such a strategy could partially compensate for the loss of on-ice foraging opportunities caused by climate change. However, here we report gradual, moderate declines in activity and body temperature of both shore and ice bears in summer, resembling energy expenditures typical of fasting, nonhibernating mammals. Also, we found that to avoid unsustainable heat loss while swimming, bears employed unusual heterothermy of the body core. Thus, although well adapted to seasonal ice melt, polar bears appear susceptible to deleterious declines in body condition during the lengthening period of summer food deprivation.

  7. Age-related decline in cardiac autonomic function is not attenuated with increased physical activity

    PubMed Central

    Njemanze, Hugo; Warren, Charlotte; Eggett, Christopher; MacGowan, Guy A.; Bates, Matthew G D; Siervo, Mario; Ivkovic, Srdjan; Trenell, Michael I.; Jakovljevic, Djordje G.

    2016-01-01

    Age and physical inactivity are important risk factors for cardiovascular mortality. Heart rate response to exercise (HRRE) and heart rate recovery (HRR), measures of cardiac autonomic function, are strong predictors of mortality. The present study defined the effect of age and physical activity on HRRE and HRR. Healthy women (N=72) grouped according to age (young, 20-30 years; middle, 40-50 years; and older, 65-81 years) and daily physical activity (low active <7500, high active >12,500 steps/day) performed a maximal cardiopulmonary exercise test. The HRRE was defined as an increase in heart rate from rest to 1, 3 and 5 minutes of exercise and at 1/3 of total exercise time, and HRR as the difference in heart rate between peak exercise and 1, 2, and 3 minutes later. Age was associated with a significant decline in HRRE at 1 min and 1/3 of exercise time (r= − 0.27, p=0.04, and r=−0.39, p=0.02) and HRR at 2 min and 3 min (r=−0.35, p=0.01, and r=−0.31, p=0.02). There was no significant difference in HRRE and HRR between high and low-active middle-age and older women (p>0.05). Increased level of habitual physical activity level appears to have a limited effect on age-related decline in cardiac autonomic function in women. PMID:27705949

  8. Light-Intensity Activity Attenuates Functional Decline in Older Cancer Survivors

    PubMed Central

    Blair, Cindy K.; Morey, Miriam C.; Desmond, Renee A.; Cohen, Harvey Jay; Sloane, Richard; Snyder, Denise C.; Demark-Wahnefried, Wendy

    2014-01-01

    While moderate-vigorous intensity physical activities (MVPA) confer the greatest health benefits, evidence suggests that light-intensity activities are also beneficial, particularly for older adults and individuals with moderate-severe comorbidities. Purpose To examine cross-sectional and longitudinal associations between light-intensity activity and physical function in older cancer survivors at increased risk for age- and treatment-related comorbidities, including accelerated functional decline. Methods The analysis included data from 641 breast, prostate, and colorectal cancer survivors (54% female) aged 65 and older who participated in a 1-year, home-based diet and exercise intervention designed to reduce the rate of physical function decline. ANCOVA was used to compare means of physical function across levels of PA intensity (low-light (LLPA): 1.5-2.0 METs; high-light (HLPA): 2.1-2.9 METs; MVPA: ≥3.0 METs). Results In cross-sectional analyses, increasing tertiles of light-intensity activity were associated with higher scores for all 3 measures of physical function (all p-values <0.005), after adjustment for age, sex, BMI, comorbidity, symptoms, and MVPA. Associations were stronger for HLPA than for LLPA. Compared with survivors who decreased or remained stable in MVPA and HLPA at the post-intervention follow-up, those who increased in HLPA, but decreased or remained stable in MVPA, reported higher physical function scores (LSMeans (95% CI): SF-36 physical function subscale: -5.58 (-7.96, -3.20) vs. -2.54 (-5.83, 0.75), p=0.14; basic lower extremity function: -2.00 (-3.45, -0.55) vs. 0.28 (-1.72, 2.28), p=0.07; advanced lower extremity function: -2.58 (-4.00, -1.15) vs. 0.44 (-1.52, 2.40), p=0.01). Conclusion Our findings suggest that increasing light-intensity activities, especially HLPA, may be a viable approach to reducing the rate of physical function decline in individuals who are unable or reluctant to initiate or maintain adequate levels of moderate

  9. The declining prevalence of overweight among Russian children: Income, diet, and physical activity behavior changes

    PubMed Central

    Jahns, Lisa; Adair, Linda; Mroz, Thomas; Popkin, Barry M.

    2011-01-01

    The aim of this study is to examine the relationships among income, diet, physical activity behaviors and overweight among Russian children during a period of economic upheaval. Subjects include 2151 schoolchildren aged 7-13 derived from cross-sectional waves of the Russia Longitudinal Monitoring Surveys in 1995 and in 2002. Diet was assessed by 24-h recall and physical activity (hrs/week) and household income by parental questionnaire. Hours spent in vigorous activities were low (1.0-1.5 hrs/week), and time spent in sedentary behaviors increased from 31 to 37 hrs/week between 1995 and 2002. In 1995 there was a direct relationship of income to energy and fat intake, and time spent in vigorous activity, and an inverse relationship of income to hrs/wk spent in moderate activities (such as walking to school). The effect of having low income parents was less in 2002 than in 1995. Overweight prevalence did not differ significantly by income in either year, but there was a significant decline in overweight among high income children. Only hours spent in moderate physical activity was moderately protective against overweight. Income disparities do not explain trends in overweight among Russian children. PMID:21840274

  10. The influence of declining sea ice on shipping activity in the Canadian Arctic

    NASA Astrophysics Data System (ADS)

    Pizzolato, Larissa; Howell, Stephen E. L.; Dawson, Jackie; Laliberté, Frédéric; Copland, Luke

    2016-12-01

    Significant attention has focused on the potential for increased shipping activity driven by recently observed declines in Arctic sea ice cover. In this study, we describe the first coupled spatial analysis between shipping activity and sea ice using observations in the Canadian Arctic over the 1990-2015 period. Shipping activity is measured by using known ship locations enhanced with a least cost path algorithm to generate ship tracks and quantified by computing total distance traveled in kilometers. Statistically significant increases in shipping activity are observed in the Hudson Strait (150-500 km traveled yr-1), the Beaufort Sea (40-450 km traveled yr-1), Baffin Bay (50-350 km traveled yr-1), and regions in the southern route of the Northwest Passage (50-250 km traveled yr-1). Increases in shipping activity are significantly correlated with reductions in sea ice concentration (Kendall's tau up to -0.6) in regions of the Beaufort Sea, Western Parry Channel, Western Baffin Bay, and Foxe Basin. Changes in multiyear ice-dominant regions in the Canadian Arctic were found to be more influential on changes to shipping activity compared to seasonal sea ice regions.

  11. Normal Weight with Central Obesity, Physical Activity, and Functional Decline: Data from the Osteoarthritis Initiative

    PubMed Central

    Batsis, John A.; Zbehlik, Alicia J.; Scherer, Emily A.; Barre, Laura K.; Bartels, Stephen J.

    2015-01-01

    OBJECTIVES To identify the risks of the combination of normal body mass index (BMI) and central obesity (normal weight and central obesity (NWCO)) on physical activity and function. DESIGN Longitudinal Osteoarthritis Initiative Study. SETTING Community based. PARTICIPANTS Adults aged 60 and older at risk of osteoarthritis (N= 2,210; mean age 68, range 67.1–69.0) were grouped according to BMI (normal 18.5–24.9 kg/m2, overweight 25.0–29.9 kg/m2, obese ≥30.0 kg/m2). High waist circumference (WC) was defined as greater than 88 cm for women and greater than 102 cm for men. Subjects were subcategorized according to WC (five categories). Subjects with normal BMI and a large WC were considered to have NWCO (n=280, 12.7%). MEASUREMENTS Six-year changes in the Physical Component Summary of the Medical Outcomes Study 12-item Short Form Survey (PCS), Physical Activity Scale for the Elderly (PASE), and Late-Life Function and Disability Index (LL-FDI) were examined. The association between BMI and WC over 6 years was assessed (reference normal BMI, normal WC). Stratified analyses were performed according to age (60–69; ≥70). RESULTS Physical component scores, PASE, and LL-FDI declined with time. Mean PASE scores at 6 years differed between the NWCO group and the group with normal BMI and WC (117.7 vs 141.5), but rate of change from baseline to 6 years was not significantly different (p=.35). In adjusted models, those with NWCO had greater decline in PCS over time, particularly those aged 70 and older than those with normal BMI and WC (time interaction β=–0.37, 95% confidence interval=–0.68 to –0.06). CONCLUSION NWCO in older adults at risk of osteoarthritis may be a risk factor for declining function and physical activity, particularly in those aged 70 and older, suggesting the value of targeting those with NWCO who would otherwise be labeled as low risk. PMID:26173812

  12. Comparison of semantic and episodic memory BOLD fMRI activation in predicting cognitive decline in older adults

    PubMed Central

    Hantke, Nathan; Nielson, Kristy A.; Woodard, John L.; Guidotti Breting, Leslie M.; Butts, Alissa; Seidenberg, Michael; Smith, J. Carson; Durgerian, Sally; Lancaster, Melissa; Matthews, Monica; Sugarman, Michael A.; Rao, Stephen M.

    2013-01-01

    Previous studies suggest that task-activated fMRI can predict future cognitive decline among healthy older adults. The present fMRI study examined the relative sensitivity of semantic memory (SM) versus episodic memory (EM) activation tasks for predicting cognitive decline. Seventy-eight cognitively intact elders underwent neuropsychological testing at entry and after an 18-month interval, with participants classified as cognitively “Stable” or “Declining” based on ≥1.0 SD decline in performance. Baseline fMRI scanning involved SM (famous name discrimination) and EM (name recognition) tasks. SM and EM fMRI activation, along with APOE ε4 status, served as predictors of cognitive outcome using a logistic regression analysis. Twenty-seven (34.6%) participants were classified as Declining and 51 (65.4%) as Stable. APOE ε4 status alone significantly predicted cognitive decline (R2 = .106; C index = .642). Addition of SM activation significantly improved prediction accuracy (R2 = .285; C index = .787), whereas the addition of EM did not (R2 = .212; C index = .711). In combination with APOE status, SM task activation predicts future cognitive decline better than EM activation. These results have implications for use of fMRI in prevention clinical trials involving the identification of persons at-risk for age-associated memory loss and Alzheimer’s disease. PMID:23199565

  13. Functional aging in the nervous system contributes to age-dependent motor activity decline in C. elegans.

    PubMed

    Liu, Jie; Zhang, Bi; Lei, Haoyun; Feng, Zhaoyang; Liu, Jianfeng; Hsu, Ao-Lin; Xu, X Z Shawn

    2013-09-03

    Aging is characterized by a progressive decline in multiple physiological functions (i.e., functional aging). As animals age, they exhibit a gradual loss in motor activity, but the underlying mechanisms remain unclear. Here we approach this question in C. elegans by functionally characterizing its aging nervous system and muscles. We find that motor neurons exhibit a progressive functional decline, beginning in early life. Surprisingly, body-wall muscles, which were previously thought to undergo functional aging, do not manifest such a decline until mid-late life. Notably, motor neurons first develop a deficit in synaptic vesicle fusion followed by that in quantal size and vesicle docking/priming, revealing specific functional deteriorations in synaptic transmission. Pharmacological stimulation of synaptic transmission can improve motor activity in aged animals. These results uncover a critical role for the nervous system in age-dependent motor activity decline in C. elegans and provide insights into how functional aging occurs in this organism.

  14. Mid-Holocene Hemlock Decline in Eastern North America Linked with Phytophagous Insect Activity

    NASA Astrophysics Data System (ADS)

    Bhiry, Najat; Filion, Louise

    1996-05-01

    Macrofossil evidence indicates that the mid-Holocene hemlock [ Tsuga canadensisL. (Carr.)] decline that occurred over a wide area in eastern North America was associated with phytophagous insect activity. In situhemlock macrofossils and insect remains found in a paludified dunefield at the northern limit of hemlock testify that two defoliation events occurred at 4910 ± 90 and 4200 ± 100 yr B.P., respectively. The sharp coincidence of remains from hemlock needles with chewing damage typical of hemlock looper feeding, head capsules from the hemlock looper ( Lambdina fiscellaria) and the spruce budworm ( Choristoneura fumiferana), absence of hemlock fruiting remains, and tree-ring anomalies in fossil hemlocks that died prematurely (<165 yr) suggest that defoliation affected hemlock reproductive capacity and pollen productivity, or more likely caused mass mortality. Our findings indicate that defoliation can affect ecosystems for centuries, especially when long-lived tree species are involved.

  15. Stress-Induced Declines in Soybean N2 Fixation Are Related to Nodule Sucrose Synthase Activity.

    PubMed Central

    Gordon, A. J.; Minchin, F. R.; Skot, L.; James, C. L.

    1997-01-01

    Soybean (Glycine max L.) plants were subjected to a number of treatments (drought, 10 mM nitrate, 150 mM NaCl, shoot meristem removal, and removal of approximately 50% of the nodules) to test the hypothesis that metabolic responses contribute to the regulation of N2 fixation. Nitrogenase activity was correlated with the activity of nodule sucrose synthase (SS), but not with that of glutamine oxoglutarate amino transferase. Leghemoglobin levels and other enzyme activities were not significantly or consistently affected by the treatments. SS mRNA was greatly reduced in nodules of drought-, salt-, and nitrate-treated plants; however, this was not correlated with changes in soluble carbohydrate, starch, amino acids, or ureides. Leghemoglobin mRNA was only slightly affected by the treatments. The time course of drought stress showed a decline in the SS transcript level by 1 d, but levels of leghemoglobin, glutamine synthetase, and ascorbate peroxidase mRNA were not markedly affected by 4 d. SS activity at 4 d was reduced by 46%. We propose that N2 fixation in soybean nodules is mediated by both the oxygen-diffusion barrier and the potential to metabolize sucrose via SS. The response to environmental perturbation may involve down-regulation of the nodule SS gene. PMID:12223754

  16. Impact of decline-board squat exercises and knee joint angles on the muscle activity of the lower limbs.

    PubMed

    Lee, Daehee; Lee, Sangyong; Park, Jungseo

    2015-08-01

    [Purpose] This study aims to investigate how squat exercises on a decline board and how the knee joint angles affect the muscle activity of the lower limbs. [Subjects] The subjects were 26 normal adults. [Methods] A Tumble Forms wedge device was used as the decline board, and the knee joint angles were measured with a goniometer. To examine the muscle activity of the biceps femoris, rectus femoris, gastrocnemius lateralis, and tibialis anterior of the lower limbs, a comparison analysis with electromyography was conducted. [Results] The muscle activity of the biceps femoris, rectus femoris, gastrocnemius lateralis, and tibialis anterior increased with increased knee joint angles, both for squat exercises on the decline board and on a flat floor. When the knee joint angle was 45°, 60°, and 90°, the muscle activity of the rectus femoris was significantly higher and that of the tibialis anterior was significantly lower during squat exercises on the decline board than on the flat floor. When the knee joint angle was 90°, the muscle activity of the gastrocnemius lateralis was significantly lower. [Conclusion] Squat exercises on a decline board are an effective intervention to increase the muscle activity of the rectus femoris with increased knee joint angles.

  17. Triclosan causes spontaneous abortion accompanied by decline of estrogen sulfotransferase activity in humans and mice

    PubMed Central

    Wang, Xiaoli; Chen, Xiaojiao; Feng, Xuejiao; Chang, Fei; Chen, Minjian; Xia, Yankai; Chen, Ling

    2015-01-01

    Triclosan (TCS), an antibacterial agent, is identified in serum and urine of humans. Here, we show that the level of urinary TCS in 28.3% patients who had spontaneous abortion in mid-gestation were increased by 11.3-fold (high-TCS) compared with normal pregnancies. Oral administration of TCS (10 mg/kg/day) in mice (TCS mice) caused an equivalent urinary TCS level as those in the high-TCS abortion patients. The TCS-exposure from gestation day (GD) 5.5 caused dose-dependently fetal death during GD12.5–16.5 with decline of live fetal weight. GD15.5 TCS mice appeared placental thrombus and tissue necrosis with enhancement of platelet aggregation. The levels of placenta and plasma estrogen sulfotransferase (EST) mRNA and protein in TCS mice or high-TCS abortion patients were not altered, but their EST activities were significantly reduced compared to controls. Although the levels of serum estrogen (E2) in TCS mice and high-TCS abortion patients had no difference from controls, their ratio of sulfo-conjugated E2 and unconjugated E2 was reduced. The estrogen receptor antagonist ICI-182,780 prevented the enhanced platelet aggregation and placental thrombosis and attenuated the fetal death in TCS mice. The findings indicate that TCS-exposure might cause spontaneous abortion probably through inhibition of EST activity to produce placental thrombosis. PMID:26666354

  18. Resting spontaneous activity in the default mode network predicts performance decline during prolonged attention workload.

    PubMed

    Gui, Danyang; Xu, Sihua; Zhu, Senhua; Fang, Zhuo; Spaeth, Andrea M; Xin, Yuanyuan; Feng, Tingyong; Rao, Hengyi

    2015-10-15

    After continuous and prolonged cognitive workload, people typically show reduced behavioral performance and increased feelings of fatigue, which are known as "time-on-task (TOT) effects". Although TOT effects are pervasive in modern life, their underlying neural mechanisms remain elusive. In this study, we induced TOT effects by administering a 20-min continuous psychomotor vigilance test (PVT) to a group of 16 healthy adults and used resting-state blood oxygen level-dependent (BOLD) functional magnetic resonance imaging (fMRI) to examine spontaneous brain activity changes associated with fatigue and performance. Behaviorally, subjects displayed robust TOT effects, as reflected by increasingly slower reaction times as the test progressed and higher self-reported mental fatigue ratings after the 20-min PVT. Compared to pre-test measurements, subjects exhibited reduced amplitudes of low-frequency fluctuation (ALFF) in the default mode network (DMN) and increased ALFF in the thalamus after the test. Subjects also exhibited reduced anti-correlations between the posterior cingulate cortex (PCC) and right middle prefrontal cortex after the test. Moreover, pre-test resting ALFF in the PCC and medial prefrontal cortex (MePFC) predicted subjects' subsequent performance decline; individuals with higher ALFF in these regions exhibited more stable reaction times throughout the 20-min PVT. These results support the important role of both task-positive and task-negative networks in mediating TOT effects and suggest that spontaneous activity measured by resting-state BOLD fMRI may be a marker of mental fatigue.

  19. Cool temperatures reduce antifungal activity of symbiotic bacteria of threatened amphibians--implications for disease management and patterns of decline.

    PubMed

    Daskin, Joshua H; Bell, Sara C; Schwarzkopf, Lin; Alford, Ross A

    2014-01-01

    Chytridiomycosis, caused by the fungus Batrachochytrium dendrobatidis (Bd), is a widespread disease of amphibians responsible for population declines and extinctions. Some bacteria from amphibians' skins produce antimicrobial substances active against Bd. Supplementing populations of these cutaneous antifungal bacteria might help manage chytridiomycosis in wild amphibians. However, the activity of protective bacteria may depend upon environmental conditions. Biocontrol of Bd in nature thus requires knowledge of how environmental conditions affect their anti-Bd activity. For example, Bd-driven amphibian declines have often occurred at temperatures below Bd's optimum range. It is possible these declines occurred due to reduced anti-Bd activity of bacterial symbionts at cool temperatures. Better understanding of the effects of temperature on chytridiomycosis development could also improve risk evaluation for amphibian populations yet to encounter Bd. We characterized, at a range of temperatures approximating natural seasonal variation, the anti-Bd activity of bacterial symbionts from the skins of three species of rainforest tree frogs (Litoria nannotis, Litoria rheocola, and Litoria serrata). All three species declined during chytridiomycosis outbreaks in the late 1980s and early 1990s and have subsequently recovered to differing extents. We collected anti-Bd bacterial symbionts from frogs and cultured the bacteria at constant temperatures from 8 °C to 33 °C. Using a spectrophotometric assay, we monitored Bd growth in cell-free supernatants (CFSs) from each temperature treatment. CFSs from 11 of 24 bacteria showed reduced anti-Bd activity in vitro when they were produced at cool temperatures similar to those encountered by the host species during population declines. Reduced anti-Bd activity of metabolites produced at low temperatures may, therefore, partially explain the association between Bd-driven declines and cool temperatures. We show that to avoid

  20. Self-Efficacy Moderates the Relation Between Declines in Physical Activity and Perceived Social Support in High School Girls

    PubMed Central

    Saunders, Ruth P.; Motl, Robert W.; Dowda, Marsha; Pate, Russell R.

    2009-01-01

    Objective To test whether self-efficacy for overcoming barriers to physical activity has direct, indirect (i.e., mediated), or moderating relations with naturally occurring change in perceived social support and declines in physical activity during high school. Methods Latent growth modeling was used with measures completed in the 8th, 9th, and 12th grades by a cohort of 195 Black and White girls. Results Self-efficacy was stable and moderated the relation between changes in physical activity and perceived social support. Girls who maintained a perception of strong social support had less of a decline in physical activity if they also had high self-efficacy. However, girls having high self-efficacy had a greater decline in physical activity if they perceived declines in social support. Conclusions Randomized controlled trials of physical activity interventions based on social cognitive theory should consider that the influence of girls’ perceptions of social support on their physical activity may differ according to their efficacy beliefs about barriers to physical activity. PMID:18812410

  1. Leg strength declines with advancing age despite habitual endurance exercise in active older adults.

    PubMed

    Marcell, Taylor J; Hawkins, Steven A; Wiswell, Robert A

    2014-02-01

    Age-associated loss of muscle mass (sarcopenia) and strength (dynapenia) is associated with a loss of independence that contributes to falls, fractures, and nursing home admissions, whereas regular physical activity has been suggested to offset these losses. The purpose of this study was to evaluate the effect of habitual endurance exercise on muscle mass and strength in active older adults. A longitudinal analysis of muscle strength (≈4.8 years apart) was performed on 59 men (age at start of study: 58.6 ± 7.3 years) and 35 women (56.9 ± 8.2 years) who used endurance running as their primary mode of exercise. There were no changes in fat-free mass although body fat increased minimally (1.0-1.5%). Training volume (km·wk, d·wk) decreased in both the men and women. There was a significant loss of both isometric knee extension (≈5% per year) and knee flexion (≈3.6% per year) strength in both the men and women. However, there was no significant change in either isokinetic concentric or eccentric torque of the knee extensors. Our data demonstrated a significant decline in isometric knee extensor and knee flexor strength although there were no changes in body mass in this group of very active older men and women. Our data support newer exercise guidelines for older Americans suggesting resistance training be an integral component of a fitness program and that running alone was not sufficient to prevent the loss in muscle strength (dynapenia) with aging.

  2. Activity patterns and time budgets of the declining sea otter population at Amchitka Island, Alaska

    USGS Publications Warehouse

    Gelatt, Thomas S.; Siniff, Donald B.; Estes, James A.

    2002-01-01

    Time budgets of predators may reflect population status if time spent foraging varies with local prey abun- dance. We assumed that the sea otter (Enhydra lutris) population at Amchitka Island, Alaska, USA, had been at equilibrium since the early 1960s and collected time budgets of otters to be used to represent future conditions of currently expanding sea otter populations. We used radiotelemetry to monitor activity-time budgets of otters from August 1992 to March 1994. Sea otter activity was directly linked to sex, age, weather condition, season, and time of day. Sea otters differed in percent time foraging among cohorts but not within cohorts. Percent time foraging ranged from 21% for females with very young (≤ 3weeks of age) dependent pups to 52% for females with old (≥10 weeks of age) pups. Otters foraged more and hauled out more as local sea conditions worsened. Adult males spent less time foraging during winter and spring, consistent with seasonal changes in prey selection. Time spent for- aging was similar to that reported for otters in California and an established population in Prince William Sound, Alaska, but greater than that of otters in recently established populations in Oregon and Alaska. Despite current evidence indicating that the population was in decline during our study, we were unable to recognize this change using time budgets. Our results illustrate the importance of stratifying analyses of activity patterns by age and sex cohorts and the complexity inherent in comparisons of behavioral data between different populations relying on distinct prey bases.

  3. Dollar's Steep Decline Seen Limiting Overseas Activities by U.S. Academics.

    ERIC Educational Resources Information Center

    Jacobson, Robert L.

    1987-01-01

    Declining involvement of American students and scholars overseas because of unstable currency exchange rates is causing concern at a time when American sophistication in international affairs is becoming more important to the nation's future. (MSE)

  4. Running out of time: the decline of channel activity and nucleotide activation in adenosine triphosphate-sensitive K-channels

    PubMed Central

    Proks, Peter; Puljung, Michael C.; Vedovato, Natascia; Sachse, Gregor; Mulvaney, Rachel; Ashcroft, Frances M.

    2016-01-01

    KATP channels act as key regulators of electrical excitability by coupling metabolic cues—mainly intracellular adenine nucleotide concentrations—to cellular potassium ion efflux. However, their study has been hindered by their rapid loss of activity in excised membrane patches (rundown), and by a second phenomenon, the decline of activation by Mg-nucleotides (DAMN). Degradation of PI(4,5)P2 and other phosphoinositides is the strongest candidate for the molecular cause of rundown. Broad evidence indicates that most other determinants of rundown (e.g. phosphorylation, intracellular calcium, channel mutations that affect rundown) also act by influencing KATP channel regulation by phosphoinositides. Unfortunately, experimental conditions that reproducibly prevent rundown have remained elusive, necessitating post hoc data compensation. Rundown is clearly distinct from DAMN. While the former is associated with pore-forming Kir6.2 subunits, DAMN is generally a slower process involving the regulatory sulfonylurea receptor (SUR) subunits. We speculate that it arises when SUR subunits enter non-physiological conformational states associated with the loss of SUR nucleotide-binding domain dimerization following prolonged exposure to nucleotide-free conditions. This review presents new information on both rundown and DAMN, summarizes our current understanding of these processes and considers their physiological roles. This article is part of the themed issue ‘Evolution brings Ca2+ and ATP together to control life and death’. PMID:27377720

  5. Intellectual Decline.

    ERIC Educational Resources Information Center

    Guilford, J.P.

    In investigations of decline of intellectual status with age, cross-sectional and longitudinal studies give divergent results--the former show almost universal declines in test performances among older groups while the latter often show gains. Although few structure-of-intellect (SI) factors have been explored in relation to adult ages, two kinds…

  6. How is post-industrial decline associated with the geography of physical activity? Evidence from the Health Survey for England

    PubMed Central

    Rind, Esther; Jones, Andy; Southall, Humphrey

    2014-01-01

    In recent decades, the prevalence of physical activity has declined considerably in many developed countries, which has been related to rising levels of obesity and several weight-related medical conditions, such as coronary heart disease. There is evidence that areas exhibiting particularly low levels of physical activity have undergone a strong transition away from employment in physically demanding occupations. It is proposed that such processes of deindustrialisation may be causally linked to unexplained geographical disparities in physical activity. This study investigates how geographical variations in deindustrialisation are associated with current levels of physical activity across different activity domains and relevant macro-economic time periods in England. The analysis includes data on 27,414 adults from the Health Survey for England 2006 and 2008 who reported total, occupational, domestic, recreational and walking activity. Based on employment change in industries associated with heavy manual work, a local measurement of industrial decline was developed, covering the period 1841–2001. We applied a multilevel modelling approach to study associations between industrial decline and physical activity. Results indicate that the process of deindustrialisation appears to be associated with patterns of physical activity and that this is independent of household income. The effects observed were generally similar for men and women. However, the nature of the association differed across areas, time periods and employment types; in particular, residents of districts characterised by a history of manufacturing and mining employment had increased odds of reporting low activity levels. We conclude that post-industrial change may be a factor in explaining present-day variations in physical activity, emphasising the plausible impact of inherited cultures and regional identities on health related behaviours. PMID:24581066

  7. Inhibition of Phosphatase Activity Follows Decline in Sulfatase Activity and Leads to Transcriptional Effects through Sustained Phosphorylation of Transcription Factor MITF

    PubMed Central

    Bhattacharyya, Sumit; Feferman, Leo; Tobacman, Joanne K.

    2016-01-01

    Arylsulfatase B (B-acetylgalactosamine 4-sulfatase; ARSB) is the enzyme that removes 4-sulfate groups from the non-reducing end of the glycosaminoglycans chondroitin 4-sulfate and dermatan sulfate. Decline in ARSB has been shown in malignant prostate, colonic, and mammary cells and tissues, and decline in ARSB leads to transcriptional events mediated by galectin-3 with AP-1 and Sp1. Increased mRNA expression of GPNMB (transmembrane glycoprotein NMB) in HepG2 cells and in hepatic tissue from ARSB-deficient mice followed decline in expression of ARSB and was mediated by the microphthalmia-associated transcription factor (MITF), but was unaffected by silencing galectin-3. Since GPNMB is increased in multiple malignancies, studies were performed to determine how decline in ARSB increased GPNMB expression. The mechanism by which decline in ARSB increased nuclear phospho-MITF was due to reduced activity of SHP2, a protein tyrosine phosphatase with Src homology (SH2) domains that regulates multiple cellular processes. SHP2 activity declined due to increased binding with chondroitin 4-sulfate when ARSB was reduced. When SHP2 activity was inhibited, phosphorylations of p38 mitogen-associated phosphokinase (MAPK) and of MITF increased, leading to GPNMB promoter activation. A dominant negative SHP2 construct, the SHP2 inhibitor PHSP1, and silencing of ARSB increased phospho-p38, nuclear MITF, and GPNMB. In contrast, constitutively active SHP2 and overexpression of ARSB inhibited GPNMB expression. The interaction between chondroitin 4-sulfate and SHP2 is a novel intersection between sulfation and phosphorylation, by which decline in ARSB and increased chondroitin 4-sulfation can inhibit SHP2, thereby regulating downstream tyrosine phosphorylations by sustained phosphorylations with associated activation of signaling and transcriptional events. PMID:27078017

  8. Impact of Physical Activity on Cognitive Decline, Dementia, and Its Subtypes: Meta-Analysis of Prospective Studies

    PubMed Central

    Ibrahim, Noor A.; Adam, Mohd B.; Said, Salmiah Md

    2017-01-01

    The association of physical activity with dementia and its subtypes has remained controversial in the literature and has continued to be a subject of debate among researchers. A systematic review and meta-analysis of longitudinal studies on the relationship between physical activity and the risk of cognitive decline, all-cause dementia, Alzheimer's disease, and vascular dementia among nondemented subjects are considered. A comprehensive literature search in all available databases was conducted up until April 2016. Well-defined inclusion and exclusion criteria were developed with focus on prospective studies ≥ 12 months. The overall sample from all studies is 117410 with the highest follow-up of 28 years. The analyses are performed with both Bayesian parametric and nonparametric models. Our analysis reveals a protective effect for high physical activity on all-cause dementia, odds ratio of 0.79, 95% CI (0.69, 0.88), a higher and better protective effect for Alzheimer's disease, odds ratio of 0.62, 95% CI (0.49, 0.75), cognitive decline odds ratio of 0.67, 95% CI (0.55, 0.78), and a nonprotective effect for vascular dementia of 0.92, 95% CI (0.62, 1.30). Our findings suggest that physical activity is more protective against Alzheimer's disease than it is for all-cause dementia, vascular dementia, and cognitive decline. PMID:28271072

  9. Sharply Tuned pH Response of Genetic Competence Regulation in Streptococcus mutans: a Microfluidic Study of the Environmental Sensitivity of comX

    PubMed Central

    Son, Minjun; Ghoreishi, Delaram; Ahn, Sang-Joon; Burne, Robert A.

    2015-01-01

    Genetic competence in Streptococcus mutans is a transient state that is regulated in response to multiple environmental inputs. These include extracellular pH and the concentrations of two secreted peptides, designated CSP (competence-stimulating peptide) and XIP (comX-inducing peptide). The role of environmental cues in regulating competence can be difficult to disentangle from the effects of the organism's physiological state and its chemical modification of its environment. We used microfluidics to control the extracellular environment and study the activation of the key competence gene comX. We find that the comX promoter (PcomX) responds to XIP or CSP only when the extracellular pH lies within a narrow window, about 1 pH unit wide, near pH 7. Within this pH range, CSP elicits a strong PcomX response from a subpopulation of cells, whereas outside this range the proportion of cells expressing comX declines sharply. Likewise, PcomX is most sensitive to XIP only within a narrow pH window. While previous work suggested that comX may become refractory to CSP or XIP stimulus as cells exit early exponential phase, our microfluidic data show that extracellular pH dominates in determining sensitivity to XIP and CSP. The data are most consistent with an effect of pH on the ComR/ComS system, which has direct control over transcription of comX in S. mutans. PMID:26070670

  10. Decline in microbial activity does not necessarily indicate an end to biodegradation in MSW-biowaste: a case study.

    PubMed

    Macleod, I; Savage, A L; Pahl, O; Baird, J

    2008-12-01

    The aim of this study was to examine whether a decline in microbial activity (i.e., CO(2) output) during the biodegradation of municipal solid waste (MSW) indicated an end to biodegradation and the appearance of a stable, final product. As the organic fraction of MSW was biodegraded in an 8 clamp Cambridge Batch System composter, CO(2) output declined by 50% and moisture content at the end of the process was <20%. Levels of biodegradable material remaining in the product were determined by the dynamic respiration index (DRI) method but despite 151 days in the composting system biodegradable material was still present at levels (24130mgO(2)/kgdry matter (DM)) which exceeded draft EU biowaste directive (2001) guidelines (10,000mgO(2)/kgDM). Further laboratory based incubations demonstrated that microbial activity and hence biodegradation of organic material could be restarted if moisture levels were adjusted suggesting that dehydration limited microbial activity. Low levels of microbial activity alone did not therefore indicate and end to biodegradation, biodegradable material was not exhausted and the final product was not stable which has serious implications for its end-use.

  11. Use it or lose it! Cognitive activity as a protec-tive factor for cognitive decline associated with Alzheimer's disease.

    PubMed

    Mistridis, Panagiota; Mata, Jutta; Neuner-Jehle, Stefan; Annoni, Jean-Marie; Biedermann, Andreas; Bopp-Kistler, Irene; Brand, Dominique; Brioschi Guevara, Andrea; Decrey-Wick, Hedi; Démonet, Jean-François; Hemmeter, Ulrich; Kressig, Reto W; Martin, Brian; Rampa, Luca; Savaskan, Egemen; Stuck, Andreas; Tschopp, Philipp; Zekry, Dina; Monsch, Andreas

    2017-03-21

    Because of the worldwide aging of populations, Alzheimer's disease and other dementias constitute a devastating experience for patients and families as well as a major social and economic burden for both healthcare systems and society. Multiple potentially modifiable cardiovascular and lifestyle risk factors have been associated with this disease. Thus, modifying these risk factors and identifying protective factors represent important strategies to prevent and delay disease onset and to decrease the social burden. Based on the cognitive reserve hypothesis, evidence from epidemiological studies shows that low education and cognitive inactivity constitute major risk factors for dementia. This indicates that a cognitively active lifestyle may protect against cognitive decline or delay the onset of dementia. We describe a newly developed preventive programme, based on this evidence, to stimulate and increase cognitive activity in older adults at risk for cognitive decline. This programme, called "BrainCoach", includes the technique of "motivational interviewing" to foster behaviour change. If the planned feasibility study is successful, we propose to add BrainCoach as a module to the already existing "Health Coaching" programme, a Swiss preventive programme to address multiple risk factors in primary care.

  12. Report: Decline In EPA Particulate Matter Methods Development Activities May Hamper Timely Achievement of Program Goals

    EPA Pesticide Factsheets

    Report #2003-P-00016, September 30, 2003. EPA has not supported PM2.5 methods development activities to the extent necessary to fully achieve the short- and long-range goals of the PM2.5 program in a timely manner.

  13. The Decline of Play and the Rise of Psychopathology in Children and Adolescents

    ERIC Educational Resources Information Center

    Gray, Peter

    2011-01-01

    Over the past half century, in the United States and other developed nations, children's free play with other children has declined sharply. Over the same period, anxiety, depression, suicide, feelings of helplessness, and narcissism have increased sharply in children, adolescents, and young adults. This article documents these historical changes…

  14. Using runoff slope-break to determine dominate factors of runoff decline in Hutuo River Basin, North China.

    PubMed

    Tian, Fei; Yang, Yonghui; Han, Shumin

    2009-01-01

    Water resources in North China have declined sharply in recent years. Low runoff (especially in the mountain areas) has been identified as the main factor. Hutuo River Basin (HRB), a typical up-stream basin in North China with two subcatchments (Ye and Hutuo River Catchments), was investigated in this study. Mann-Kendall test was used to determine the general trend of precipitation and runoff for 1960-1999. Then Sequential Mann-Kendall test was used to establish runoff slope-break from which the beginning point of sharp decline in runoff was determined. Finally, regression analysis was done to illustrate runoff decline via comparison of precipitation-runoff correlation for the period prior to and after sharp runoff decline. This was further verified by analysis of rainy season peak runoff flows. The results are as follows: (1) annual runoff decline in the basin is significant while that of precipitation is insignificant at alpha=0.05 confidence level; (2) sharp decline in runoff in Ye River Catchment (YRC) occurred in 1968 while that in Hutuo River Catchment (HRC) occurred in 1978; (3) based on the regression analysis, human activity has the highest impact on runoff decline in the basin. As runoff slope-breaks in both Catchments strongly coincided with increase in agricultural activity, agricultural water use is considered the dominate factor of runoff decline in the study area.

  15. Loss of SYNJ1 dual phosphatase activity leads to early onset refractory seizures and progressive neurological decline.

    PubMed

    Hardies, Katia; Cai, Yiying; Jardel, Claude; Jansen, Anna C; Cao, Mian; May, Patrick; Djémié, Tania; Hachon Le Camus, Caroline; Keymolen, Kathelijn; Deconinck, Tine; Bhambhani, Vikas; Long, Catherine; Sajan, Samin A; Helbig, Katherine L; Suls, Arvid; Balling, Rudi; Helbig, Ingo; De Jonghe, Peter; Depienne, Christel; De Camilli, Pietro; Weckhuysen, Sarah

    2016-09-01

    SYNJ1 encodes a polyphosphoinositide phosphatase, synaptojanin 1, which contains two consecutive phosphatase domains and plays a prominent role in synaptic vesicle dynamics. Autosomal recessive inherited variants in SYNJ1 have previously been associated with two different neurological diseases: a recurrent homozygous missense variant (p.Arg258Gln) that abolishes Sac1 phosphatase activity was identified in three independent families with early onset parkinsonism, whereas a homozygous nonsense variant (p.Arg136*) causing a severe decrease of mRNA transcript was found in a single patient with intractable epilepsy and tau pathology. We performed whole exome or genome sequencing in three independent sib pairs with early onset refractory seizures and progressive neurological decline, and identified novel segregating recessive SYNJ1 defects. A homozygous missense variant resulting in an amino acid substitution (p.Tyr888Cys) was found to impair, but not abolish, the dual phosphatase activity of SYNJ1, whereas three premature stop variants (homozygote p.Trp843* and compound heterozygote p.Gln647Argfs*6/p.Ser1122Thrfs*3) almost completely abolished mRNA transcript production. A genetic follow-up screening in a large cohort of 543 patients with a wide phenotypical range of epilepsies and intellectual disability revealed no additional pathogenic variants, showing that SYNJ1 deficiency is rare and probably linked to a specific phenotype. While variants leading to early onset parkinsonism selectively abolish Sac1 function, our results provide evidence that a critical reduction of the dual phosphatase activity of SYNJ1 underlies a severe disorder with neonatal refractory epilepsy and a neurodegenerative disease course. These findings further expand the clinical spectrum of synaptic dysregulation in patients with severe epilepsy, and emphasize the importance of this biological pathway in seizure pathophysiology.

  16. A High-Concentrate Diet Induced Milk Fat Decline via Glucagon-Mediated Activation of AMP-Activated Protein Kinase in Dairy Cows

    PubMed Central

    Li, Lin; Cao, Yang; Xie, Zhenglu; Zhang, Yuanshu

    2017-01-01

    Dairy cows are often fed a high-concentrate (HC) diet to meet lactation demands; however, long-term concentrate feeding is unhealthy and decreases milk fat. Therefore, we investigated the effects of liver lipid metabolism on milk fat synthesis. Ten lactating Holstein cows were assigned randomly into HC and LC (low-concentrate) diet groups. After 20 weeks of feeding, milk fat declined, and lipopolysaccharide levels in the jugular, portal, and hepatic veins increased in the HC group. Liver consumption and release of nonesterified fatty acid (NEFA) into the bloodstream also decreased. AMP-activated protein kinase alpha (AMPKα) was up-regulated significantly in the livers of the HC-fed cows. The HC diet also up-regulated the expression of the transcription factor peroxisome proliferator-activated receptor α (PPARα) and its downstream targets involved in fatty acid oxidation, including carnitine palmitoyltransferase-1,2 (CPT-1, CPT-2), liver-fatty acid-binding protein (L-FABP), and acyl-CoA oxidase (ACO). The HC diet increased blood glucagon (GC) levels, and liver glucagon receptor (GCGR) expression was elevated. Cumulatively, a long-term HC diet decreased plasma concentrations of NEFA via the GC/GCGR-AMPK-PPARα signalling pathway and reduced their synthesis in the liver. The decreased NEFA concentration in the blood during HC feeding may explain the decline in the milk fat of lactating cows. PMID:28287130

  17. Implementing Change to Arrest the Decline in Moderate to Vigorous Physical Activity (MVPA) for Adolescent Girls in Two Rural and Regional High Schools: A Case Study Approach

    ERIC Educational Resources Information Center

    Miller, Judith; Puglisi, Lauren; Perry, Janine

    2012-01-01

    Inactivity has been linked to a range of lifestyle conditions such as hypertension, type II diabetes and cardiovascular disease (World Health Organisation, 2009). Engagement in physical activity and in sport has been consistently reported to decline as the general population ages (Telama et al., 2005). In particular, the age of adolescence has…

  18. Does Increasing Reliance on Student Debt Explain Declines in Entrepreneurial Activity? Posing the Question, Gathering Evidence, Considering Policy Options. Research Report

    ERIC Educational Resources Information Center

    Baum, Sandy

    2015-01-01

    In recent years, concerns have emerged both about declines in entrepreneurial activity, and about increases in the amount students borrow to finance postsecondary education--in the aggregate as well as on average. Because the financial obligations associated with student debt could limit access to credit for individuals seeking to start…

  19. Calculation of the Relative Density and the Crossing Time Through the Fitness Barrier in AN Asymmetric Sharply-Peaked Landscape

    NASA Astrophysics Data System (ADS)

    Lee, Kwang Sung; Gill, Wonpyong

    We have calculated the relative density and crossing time through the fitness barrier by switching on an asymmetric sharply-peaked landscape, from the initial state which is the quasispecies in a sharply-peaked landscape. It is found that the increment of the relative density with the reversal sequence is a linearly increasing function of time unless a new stationary state in an asymmetric sharply-peaked landscape is reached. It is also found that the relative density with the reversal sequence at the new stationary state X*L is in inverse proportion to the asymmetric parameter when the asymmetric parameter is greater than the saturation asymmetric parameter. We have derived the approximate formulae for the relaxation time, the saturation asymmetric parameter, and the relative density with the reversal sequence X*L, which nicely fit computer simulation results. It is found that the crossing time diverges at the critical fitness parameter in the asymmetric sharply-peaked landscape, in contrast with the symmetric sharply-peaked landscape where the crossing time scales as a power law in the fitness parameter. It is also found that the critical fitness parameter decreases as the asymmetric parameter and sequence length increase.

  20. Decline of Activity and Quantity of Ribulose Bisphosphate Carboxylase/Oxygenase and Net Photosynthesis in Ozone-Treated Potato Foliage 1

    PubMed Central

    Dann, Michael S.; Pell, Eva J.

    1989-01-01

    The effect of ozone (O3) on ribulose bisphosphate carboxylase/oxygenase (Rubisco) activity and quantity and net photosynthesis in greenhouse-grown Solanum tuberosum L. cv `Norland' foliage was studied in relation to oxidant-induced premature senescence. Plants, 26 days old, were exposed to 0.06 to 0.08 microliters per liter O3 from 1000 to 1600 hours for 4 days in a controlled environment chamber. On day 5, plants were exposed to a 6-hour simulated inversion in which O3 peaked at 0.12 microliters per liter. Net photosynthesis declined in response to O3 but recovered to near control levels 3 days after the exposure ended. Rubisco activity and quantity in control potato foliage increased and then decreased during the 12-day interval of the study. In some experiments foliage studied was physiologically mature and Rubisco activity had peaked when O3 exposure commenced. In those cases, O3 accelerated the decline in Rubisco activity. When less mature foliage was treated with O3, the leaves never achieved the maximal level of Rubisco activity observed in control foliage and also exhibited more rapid decline in initial and total activity. Percent activation of Rubisco (initial/total activity) was not affected significantly by treatment. Quantity of Rubisco decreased in concert with activity. The decrease in activities is most likely due to a decrease in available protein rather than a decrease in the percentage of Rubisco activated in vivo. The reduction in the quantity of Rubisco, an important foliar storage protein, could contribute to premature senescence associated with toxicity of this air pollutant. PMID:16667037

  1. Brief light stimulation during the mouse nocturnal activity phase simultaneously induces a decline in core temperature and locomotor activity followed by EEG-determined sleep.

    PubMed

    Studholme, Keith M; Gompf, Heinrich S; Morin, Lawrence P

    2013-03-15

    Light exerts a variety of effects on mammals. Unexpectedly, one of these effects is the cessation of nocturnal locomotion and the induction of behavioral sleep (photosomnolence). Here, we extend the initial observations in several ways, including the fundamental demonstration that core body temperature (T(c)) drops substantially (about 1.5°C) in response to the light stimulation at CT15 or CT18 in a manner suggesting that the change is a direct response to light rather than simply a result of the locomotor suppression. The results show that 1) the decline of locomotion and T(c) begin soon after nocturnal light stimulation; 2) the variability in the magnitude and onset of light-induced locomotor suppression is very large, whereas the variability in T(c) is very small; 3) T(c) recovers from the light-induced decline in advance of the recovery of locomotion; 4) under entrained and freerunning conditions, the daily late afternoon T(c) increase occurs in advance of the corresponding increase in wheel running; and 5) toward the end of the subjective night, the nocturnally elevated T(c) persists longer than does locomotor activity. Finally, EEG measurements confirm light-induced sleep and, when T(c) or locomotion was measured, show their temporal association with sleep onset. Both EEG- and immobility-based sleep detection methods confirm rapid induction of light-induced sleep. The similarities between light-induced loss of locomotion and drop in T(c) suggest a common cause for parallel responses. The photosomnolence response may be contingent upon both the absence of locomotion and a simultaneous low T(c).

  2. Brief light stimulation during the mouse nocturnal activity phase simultaneously induces a decline in core temperature and locomotor activity followed by EEG-determined sleep

    PubMed Central

    Studholme, Keith M.; Gompf, Heinrich S.

    2013-01-01

    Light exerts a variety of effects on mammals. Unexpectedly, one of these effects is the cessation of nocturnal locomotion and the induction of behavioral sleep (photosomnolence). Here, we extend the initial observations in several ways, including the fundamental demonstration that core body temperature (Tc) drops substantially (about 1.5°C) in response to the light stimulation at CT15 or CT18 in a manner suggesting that the change is a direct response to light rather than simply a result of the locomotor suppression. The results show that 1) the decline of locomotion and Tc begin soon after nocturnal light stimulation; 2) the variability in the magnitude and onset of light-induced locomotor suppression is very large, whereas the variability in Tc is very small; 3) Tc recovers from the light-induced decline in advance of the recovery of locomotion; 4) under entrained and freerunning conditions, the daily late afternoon Tc increase occurs in advance of the corresponding increase in wheel running; and 5) toward the end of the subjective night, the nocturnally elevated Tc persists longer than does locomotor activity. Finally, EEG measurements confirm light-induced sleep and, when Tc or locomotion was measured, show their temporal association with sleep onset. Both EEG- and immobility-based sleep detection methods confirm rapid induction of light-induced sleep. The similarities between light-induced loss of locomotion and drop in Tc suggest a common cause for parallel responses. The photosomnolence response may be contingent upon both the absence of locomotion and a simultaneous low Tc. PMID:23364525

  3. Sharply increased mass loss from glaciers and ice caps in the Canadian Arctic Archipelago.

    PubMed

    Gardner, Alex S; Moholdt, Geir; Wouters, Bert; Wolken, Gabriel J; Burgess, David O; Sharp, Martin J; Cogley, J Graham; Braun, Carsten; Labine, Claude

    2011-05-19

    Mountain glaciers and ice caps are contributing significantly to present rates of sea level rise and will continue to do so over the next century and beyond. The Canadian Arctic Archipelago, located off the northwestern shore of Greenland, contains one-third of the global volume of land ice outside the ice sheets, but its contribution to sea-level change remains largely unknown. Here we show that the Canadian Arctic Archipelago has recently lost 61 ± 7 gigatonnes per year (Gt yr(-1)) of ice, contributing 0.17 ± 0.02 mm yr(-1) to sea-level rise. Our estimates are of regional mass changes for the ice caps and glaciers of the Canadian Arctic Archipelago referring to the years 2004 to 2009 and are based on three independent approaches: surface mass-budget modelling plus an estimate of ice discharge (SMB+D), repeat satellite laser altimetry (ICESat) and repeat satellite gravimetry (GRACE). All three approaches show consistent and large mass-loss estimates. Between the periods 2004-2006 and 2007-2009, the rate of mass loss sharply increased from 31 ± 8 Gt yr(-1) to 92 ± 12 Gt yr(-1) in direct response to warmer summer temperatures, to which rates of ice loss are highly sensitive (64 ± 14 Gt yr(-1) per 1 K increase). The duration of the study is too short to establish a long-term trend, but for 2007-2009, the increase in the rate of mass loss makes the Canadian Arctic Archipelago the single largest contributor to eustatic sea-level rise outside Greenland and Antarctica.

  4. Decline in cytochrome c oxidase activity in rat-brain mitochondria with aging. Role of peroxidized cardiolipin and beneficial effect of melatonin.

    PubMed

    Petrosillo, Giuseppe; De Benedictis, Valentina; Ruggiero, Francesca M; Paradies, Giuseppe

    2013-10-01

    Reactive oxygen species (ROS) are considered a key factor in mitochondrial dysfunction associated with brain aging process. Mitochondrial respiration is an important source of ROS and hence a potential contributor to brain functional changes with aging. In this study, we examined the effect of aging on cytochrome c oxidase activity and other bioenergetic processes such as oxygen consumption, membrane potential and ROS production in rat brain mitochondria. We found a significant age-dependent decline in the cytochrome c oxidase activity which was associated with parallel changes in state 3 respiration, membrane potential and with an increase in H2O2 generation. The cytochrome aa3 content was practically unchanged in mitochondria from young and aged animals. The age-dependent decline of cytochrome c oxidase activity could be restored, in situ, to the level of young animals, by exogenously added cardiolipin. In addition, exposure of brain mitochondria to peroxidized cardiolipin resulted in an inactivation of this enzyme complex. It is suggested that oxidation/depletion of cardiolipin could be responsible, at least in part, for the decline of cytochrome c oxidase and mitochondrial dysfunction in brain aging. Melatonin treatment of old animals largely prevented the age-associated alterations of mitochondrial bioenergetic parameters. These results may prove useful in elucidating the molecular mechanisms underlying mitochondrial dysfunction associated with brain aging process, and may have implications in etiopathology of age-associated neurodegenerative disorders and in the development of potential treatment strategies.

  5. A Multiscale Method (``Sparse Bayes Blocks'') for Revealing Sharply-Peaked High Energy Pulsars

    NASA Astrophysics Data System (ADS)

    Connors, A.; Carramiñana, A.

    2002-12-01

    Multiscale models are the best basis for elucidating both very fine and broad faint structures, even for X-ray and γ --ray Poison count data, esp. in 2D imaging (Starck, J. L., Pantin, E., Murtagh, F., 2002, PASP, 114,1051). But one sees at once they are also well-suited to describe 1D structures such as pulsar light-curves, with their extreme sharp peaks and occasional broad bridges between them (Thompson 2001/astro-ph/0101039). Hence, we have derived a statistic for detecting pulsars at X- or gamma-ray energies with the `spikiness' explictly built in. The best current methods, being Fourier-transform based, may not be optimal for detecting this class of `spiky' light-curve (Zn2; e.g. de Jager et al./astro-ph/0010179 and references therein). Instead, we use one or a very few `Bayes Blocks' (Scargle/astro-ph/9711233) of arbitrary height and width to represent the light-curve; then derive an optimum statistic (likelihood ratio) for testing against flatness via Bayesian Inference. Preliminary Monte Carlo tests show that it works as well or better than a standard Z62 statistic for a range of standard sharply peaked light-curves, especially at low signal-to-noise (Connors and Carramiñana, 2002, SCMAIII Proceedings). Here, we demonstrate it on known pulsars using CGRO/EGRET and COMPTEL data. Many of the bright unidentified sources in the gamma-ray sky may also turn out to be relatively nearby (Gould-belt: Gehrels et al2000, Nature, 404, 363) radio-quiet, gamma-ray loud pulsars, such as Geminga (Halpern and Holt 1992, Nature, 357, 222; Bertsch et al 1992, Nature, 357, 306). Can a new high-resolution algorithm help illuminate the identities of some of these? Funded in part by AISR ``AS-DATA'', with J. Scargle and V. Kashyap; and AISR ``Astrostatistics Recipes in Python'', with T. Loredo and T. Oliphant. AC thanks the hospitaltiy of Wellesley College, and the Harvard Astrostatistics Working Group.

  6. Cellular NAD depletion and decline of SIRT1 activity play critical roles in PARP-1-mediated acute epileptic neuronal death in vitro.

    PubMed

    Wang, Shengjun; Yang, Xue; Lin, Youting; Qiu, Xiaoxue; Li, Hui; Zhao, Xiuhe; Cao, Lili; Liu, Xuewu; Pang, Yuejiu; Wang, Xuping; Chi, Zhaofu

    2013-10-16

    Intense poly(ADP-ribose) polymerase-1 (PARP-1) activation was implicated as a major cause of caspase-independent cell death in the hippocampal neuronal culture (HNC) model of acute acquired epilepsy (AE). The molecular mechanisms are quite complicated. The linkage among neuronal death, cellular nicotinamide adenine dinucleotide (NAD) levels, apoptosis-inducing factor (AIF) translocation, SIRT1 expression and activity were investigated here. The results showed that PARP-1 over-activation caused by Mg²⁺-free stimuli led to cellular NAD depletion which could block AIF translocation from mitochondria to nucleus and attenuate neuronal death. Also, SIRT1 deacetylase activity was reduced by Mg²⁺-free treatment, accompanied by elevated ratio of neuronal death, which could be rescued by NAD repletion. These data demonstrated that cellular NAD depletion and decline of SIRT1 activity play critical roles in PARP-1-mediated epileptic neuronal death in the HNC model of acute AE.

  7. Age-related loss of muscle mass and bone strength in mice is associated with a decline in physical activity and serum leptin.

    PubMed

    Hamrick, Mark W; Ding, Ke-Hong; Pennington, Catherine; Chao, Yuh J; Wu, Yii-Der; Howard, Boyd; Immel, David; Borlongan, Cesario; McNeil, Paul L; Bollag, Wendy B; Curl, Walton W; Yu, Jack; Isales, Carlos M

    2006-10-01

    The mechanisms underlying age-related loss of muscle and bone tissue are poorly understood but are thought to involve changes in sex hormone status, physical activity, and circulating levels of inflammatory cytokines. This study attempts to develop an animal model useful for evaluating these mechanisms in vivo. Male C57BL/6 mice were included for study at 3, 6, 12, 18, 24, and 29 months of age. Endocortical mineralizing surface, serum leptin, body weight, and percentage of body fat all increased between 6 and 12 months of age as activity level declined. Serum levels of the inflammatory marker IL-6 increased significantly after 12 months of age, following the observed increase in body weight and percent body fat. Hindlimb muscle mass declined significantly between 18 and 24 months of age, both absolutely and relative to total body mass, with a further decline ( approximately 15%) between 24 and 29 months. Loss of muscle mass after 18 months of age was accompanied by a significant increase in bone resorption, as indicated by serum pyridinoline cross-links, and a significant decrease in fat mass, serum leptin, bone strength, bone mineral density, and vertical cage activity. No significant changes in serum testosterone with aging were detected in the mice, as levels were essentially constant between 6 and 29 months. Our data show that mice lose a significant amount of muscle and bone tissue with age, and this loss of musculoskeletal tissue is accompanied by a drop in serum leptin and preceded by a significant decrease in physical activity.

  8. Uptake of poly-dispersed single-walled carbon nanotubes and decline of functions in mouse NK cells undergoing activation.

    PubMed

    Alam, Anwar; Puri, Niti; Saxena, Rajiv K

    2016-09-01

    The interaction of poly-dispersed acid-functionalized single-walled carbon nanotubes (AF-SWCNT) with NK cells undergoing activation was examined. Exposure to AF-SWCNT during NK activation in vitro by interleukin (IL)-2, and in vivo by Poly(I:C) significantly lowered cytotoxic activity generated against YAC-1 tumor cells. Recoveries of spleen NK1.1(+) cells as well as the activated subset of NK cells (NK1.1(+)CD69(+) cells) were significantly reduced by the AF-SWCNT exposure. The proportion of apoptotic NK cells (NK1.1(+) phosphatidylserine(+)) in the spleen cell preparations activated in vitro was also significantly elevated. Expression levels of CD107a [for assessing NK cell degranulation] as well as of FasL marker [mediating non-secretory pathway of NK cell killing] were significantly lower in cells exposed to AF-SWCNT during the activation phase. Intracellular levels of interferon (IFN)-γ and tumor necrosis factor (TNF)-α in the cells were also significantly reduced. Fluorescent AF-SWCNT (FAF-SWCNT) were internalized by the NK cells and uptake was significantly greater in activated cells. Confocal microscopy indicated the internalized FAF-SWCNT were localized to the cytoplasm of the NK cells. These results indicated that AF-SWCNT were internalized by NK cells and caused a general down-regulation of a variety of parameters associated with NK cell cytotoxicity and other cellular functions.

  9. Postnatal growth hormone deficiency in growing rats causes marked decline in the activity of spinal cord acetylcholinesterase but not butyrylcholinesterase.

    PubMed

    Koohestani, Faezeh; Brown, Chester M; Meisami, Esmail

    2012-11-01

    The effects of growth hormone (GH) deficiency on the developmental changes in the abundance and activity of cholinesterase enzymes were studied in the developing spinal cord (SC) of postnatal rats by measuring the specific activity of acetylcholinesterase (AChE), a marker for cholinergic neurons and their synaptic compartments, and butyrylcholinesterase (BuChE), a marker for glial cells and neurovascular cells. Specific activities of these two enzymes were measured in SC tissue of 21- and 90 day-old (P21, weaning age; P90, young adulthood) GH deficient spontaneous dwarf (SpDwf) mutant rats which lack anterior pituitary and circulating plasma GH, and were compared with SC tissue of normal age-matched control animals. Assays were carried out for AChE and BuChE activity in the presence of their specific chemical inhibitors, BW284C51 and iso-OMPA, respectively. Results revealed that mean AChE activity was markedly and significantly reduced [28% at P21, 49% at P90, (p<0.01)] in the SC of GH deficient rats compared to age-matched controls. GH deficiency had a higher and more significant effect on AChE activity of the older (P90) rats than the younger ones (P21) ones. In contrast, BuChE activity in SC showed no significant changes in GH deficient rats at either of the two ages studied. Results imply that, in the absence of pituitary GH, the postnatal proliferation of cholinergic synapses in the rat SC, a CNS structure, where AChE activity is abundant, is markedly reduced during both the pre- and postweaning periods; more so in the postweaning than preweaning ages. In contrast, the absence of any effects on BuChE activity implies that GH does not affect the development of non-neuronal elements, e.g., glia, as much as the neuronal and synaptic compartments of the developing rat SC.

  10. The Dilemma of Decline.

    ERIC Educational Resources Information Center

    Abramowitz, Susan

    This paper, one of two related documents, examines the impact of declining enrollments on educational expenditures. It highlights population and social changes that have contributed to the decline and discusses the general financing of schools. Finally, the paper discusses strategies state policymakers can use to manage decline, including…

  11. Age-Related Declines in General Cognitive Abilities of Balb/C Mice and General Activity Are Associated with Disparities in Working Memory, Body Weight, and General Activity

    ERIC Educational Resources Information Center

    Matzel, Louis D.; Grossman, Henya; Light, Kenneth; Townsend, David; Kolata, Stefan

    2008-01-01

    A defining characteristic of age-related cognitive decline is a deficit in general cognitive performance. Here we use a testing and analysis regimen that allows us to characterize the general learning abilities of young (3-5 mo old) and aged (19-21 mo old) male and female Balb/C mice. Animals' performance was assessed on a battery of seven diverse…

  12. Is there a role for physical activity in preventing cognitive decline in people with mild cognitive impairment?

    PubMed

    Barber, Sally E; Clegg, Andrew P; Young, John B

    2012-01-01

    Mild cognitive impairment (MCI) is a common clinical syndrome that identifies people at high risk of developing dementia. Although treatments for MCI are currently unavailable, preliminary evidence has identified potential neuro-protective effects of physical activity, which may lead to improved outcomes. However, there is uncertainty regarding the effectiveness, feasibility and acceptability of this treatment strategy. These uncertainties require further investigation before physical activity interventions can be recommended for routine care.

  13. [Decline of Activity and Shifts in the Methanotrophic Community Structure of an Ombrotrophic Peat Bog after Wildfire].

    PubMed

    Danilova, O V; Belova, S E; Kulichevskaya, I S; Dedysh, S N

    2015-01-01

    This study examined potential disturbances of methanotrophic communities playing a key role in reducing methane emissions from the peat bog Tasin Borskoye, Vladimir oblast, Russia as a result of the 2007 wildfire. The potential activity of the methane-oxidizing filter in the burned peatland site and the abundance of indigenous methanotrophic bacteria were significantly reduced in comparison to the undisturbed site. Molecular analysis of methanotrophic community structure by means of PCR amplification and cloning of the pmoAgene encoding particulate methane monooxygenase revealed the replacement of typical peat-inhabiting, acidophilic type II methanotrophic bacteria with type I methanotrophs, which are less active in acidic environments. In summary, both the structure and the activity of the methane-oxidizing filter in burned peatland sites underwent significant changes, which were clearly pronounced even after 7 years of the natural ecosystem recovery. These results point to the long-term character of the disturbances caused by wildfire in peatlands.

  14. Decline in the Recovery from Synaptic Depression in Heavier Aplysia Results from Decreased Serotonin-Induced Novel PKC Activation.

    PubMed

    Dunn, Tyler William; Sossin, Wayne S

    2015-01-01

    The defensive withdrawal reflexes of Aplysia are important behaviors for protecting the animal from predation. Habituation and dishabituation allow for experience-dependent tuning of these reflexes and the mechanisms underlying these forms of behavioral plasticity involve changes in transmitter release from the sensory to motor neuron synapses through homosynaptic depression and the serotonin-mediated recovery from depression, respectively. Interestingly, dishabituation is reduced in older animals with no corresponding change in habituation. Here we show that the cultured sensory neurons of heavier animals (greater than 120 g) that form synaptic connections with motor neurons have both reduced recovery from depression and reduced novel PKC Apl II activation with 5HT. The decrease in the recovery from depression correlated better with the size of the animal than the age of the animal. Much of this change in PKC activation and synaptic facilitation following depression can be rescued by direct activation of PKC Apl II with phorbol dibutyrate, suggesting a change in the signal transduction pathway upstream of PKC Apl II activation in the sensory neurons of larger animals.

  15. Slowing of Hippocampal Activity Correlates with Cognitive Decline in Early Onset Alzheimer's Disease. An MEG Study with Virtual Electrodes.

    PubMed

    Engels, Marjolein M A; Hillebrand, Arjan; van der Flier, Wiesje M; Stam, Cornelis J; Scheltens, Philip; van Straaten, Elisabeth C W

    2016-01-01

    Pathology in Alzheimer's disease (AD) starts in the entorhinal cortex and hippocampus. Because of their deep location, activity from these areas is difficult to record with conventional electro- or magnetoencephalography (EEG/MEG). The purpose of this study was to explore hippocampal activity in AD patients and healthy controls using "virtual MEG electrodes". We used resting-state MEG recordings from 27 early onset AD patients [age 60.6 ± 5.4, 12 females, mini-mental state examination (MMSE) range: 19-28] and 26 cognitively healthy age- and gender-matched controls (age 61.8 ± 5.5, 14 females). Activity was reconstructed using beamformer-based virtual electrodes for 78 cortical regions and 6 hippocampal regions. Group differences in peak frequency and relative power in six frequency bands were identified using permutation testing. For the patients, spearman correlations between the MMSE scores and peak frequency or relative power were calculated. Moreover, receiver operator characteristic curves were plotted to estimate the diagnostic accuracy. We found a lower hippocampal peak frequency in AD compared to controls, which, in the patients, correlated positively with MMSE [r(25) = 0.61; p < 0.01] whereas hippocampal relative theta power correlated negatively with MMSE [r(25) = -0.54; p < 0.01]. Cortical peak frequency was also lower in AD in association areas. Furthermore, cortical peak frequency correlated positively with MMSE [r(25) = 0.43; p < 0.05]. In line with this finding, relative theta power was higher in AD across the cortex, and relative alpha and beta power was lower in more circumscribed areas. The average cortical relative theta power was the best discriminator between AD and controls (sensitivity 82%; specificity 81%). Using beamformer-based virtual electrodes, we were able to detect hippocampal activity in AD. In AD, this hippocampal activity is slowed, and correlates better with cognition than the (slowed) activity in cortical areas. On the other

  16. Declining densities and reproductive activities of the queen conch Strombus gigas (Mesogastropoda: Strombidae) in Banco Chinchorro, eastern Caribbean, Mexico.

    PubMed

    De Jesús-Navarrete, Alberto; Valencia-Hernández, Adriana

    2013-12-01

    Queen conch is a gastropod inhabiting the Caribbean Sea, it represents the second largest fishery after the spiny lobster, but it has been extensively captured in the area. In order to know its population status in Chinchorro Bank, we determined conch density changes and its effects on reproductive activities, between July and November 2009. For this, data on conch density, morphology and reproductive activities were obtained from 15 sites within three fishing zones, and compared with previously collected data (1990, 1992, 1994, and 1997). Data showed that adult density decreased with time, from 10,700 ind./ha in 1990, to 198 ind./h in 2009. Neither egg masses nor spawns were found and mating was only observed once in July 2009. In July, adult (lip>4 mm) density in the Southern zone was 23 ind./ha whereas in the Northern zone and Central zone densities were 15 and 9ind./ha respectively. In November, density was somewhat higher: Southern zone 96 ind./ha; Central zone 39 ind./ha and Northern zone had 38ind./ha. In July, mean shell length was 170.80 +/- 46.28 mm, with a higher median abundance at 180-189 mm. In November, higher frequency was 187.63 +/- 45.14 mm, maximumat 210-219 mm interval. For the last 10 years period, mean adult conch densities have diminished in each zone, which might be the main cause of decreased reproductive activities of the conch at Banco Chinchorro. It is therefore an immediate need to analyse the management plan for this species in this Reserve and perhaps to promote a re-population of queen conch and culture activities.

  17. Culturable bacterial flora associated with the dinoflagellate green Noctiluca miliaris during active and declining bloom phases in the Northern Arabian Sea.

    PubMed

    Basu, Subhajit; Deobagkar, Deepti D; Matondkar, S G Prabhu; Furtado, Irene

    2013-05-01

    A massive algal bloom of the dinoflagellate Noctiluca miliaris (green) was located in the Northern Arabian Sea by IRS-P4-2 (OCM-II) for microbiological studies, during two consecutive cruises of February-March 2009. Culturable bacterial load during bloom were ≈ 2-3-fold higher in comparison to non-bloom waters and ranged from 3.20 × 10(5) to 6.84 × 10(5) cfu ml(-1). An analysis of the dominant heterotrophs associated with Noctiluca bloom resulted in phylogenetic and a detailed metabolic characterization of 70 bacterial isolates from an overlapping active and declining bloom phase location near north-central Arabian Sea. The active phase flora was dominated by Gram-positive forms (70.59 %), a majority of which belonged to Bacillus (35.29 %) of Firmicutes. As the bloom declined, Gram-negative forms (61.11 %) emerged dominant, and these belonged to a diverse γ-proteobacterial population consisting of Shewanella (16.67 %) and equal fractions of a Cobetia-Pseudomonas-Psychrobacter-Halomonas population (36.11 %). A Unifrac-based principal coordinate analysis of partial 16S rDNA sequences showed significant differences among the active and declining phase flora and also with reported endocytic flora of Noctiluca (red). A nonparametric multidimensional scaling (NMDS) of antibiogram helped differentiation among closely related strains. The organic matter synthesized by N. miliaris appears to be quickly utilized and remineralized as seen from the high efficiency of isolates to metabolize various complex and simple C/N substrates such as carbohydrates, proteins/amino acids, lipids, sulfide production from organic matter, and solubilize phosphates. The ability of a large fraction of these strains (50-41.67 %) to further aerobically denitrify indicates their potential for nitrogen removal from these high-organic microniches of the Noctiluca bloom in the Arabian Sea, also known for high denitrification activity. The results indicate that culturable euphotic bacterial

  18. 30 CFR 203.54 - How does my relief arrangement for an oil and gas lease operate if prices rise sharply?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false How does my relief arrangement for an oil and gas lease operate if prices rise sharply? 203.54 Section 203.54 Mineral Resources BUREAU OF SAFETY AND... operate if prices rise sharply? In those months when your current reference price rises by at least...

  19. 30 CFR 203.54 - How does my relief arrangement for an oil and gas lease operate if prices rise sharply?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... gas lease operate if prices rise sharply? 203.54 Section 203.54 Mineral Resources MINERALS MANAGEMENT... arrangement for an oil and gas lease operate if prices rise sharply? In those months when your current reference price rises by at least 25 percent above your base reference price, you must pay the...

  20. 30 CFR 203.54 - How does my relief arrangement for an oil and gas lease operate if prices rise sharply?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... gas lease operate if prices rise sharply? 203.54 Section 203.54 Mineral Resources BUREAU OF OCEAN... Leases § 203.54 How does my relief arrangement for an oil and gas lease operate if prices rise sharply? In those months when your current reference price rises by at least 25 percent above your...

  1. 30 CFR 203.54 - How does my relief arrangement for an oil and gas lease operate if prices rise sharply?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 2 2013-07-01 2013-07-01 false How does my relief arrangement for an oil and gas lease operate if prices rise sharply? 203.54 Section 203.54 Mineral Resources BUREAU OF SAFETY AND... operate if prices rise sharply? In those months when your current reference price rises by at least...

  2. 30 CFR 203.54 - How does my relief arrangement for an oil and gas lease operate if prices rise sharply?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 2 2014-07-01 2014-07-01 false How does my relief arrangement for an oil and gas lease operate if prices rise sharply? 203.54 Section 203.54 Mineral Resources BUREAU OF SAFETY AND... operate if prices rise sharply? In those months when your current reference price rises by at least...

  3. In Obesity, HPA Axis Activity Does Not Increase with BMI, but Declines with Aging: A Meta-Analysis of Clinical Studies

    PubMed Central

    Tenk, Judit; Mátrai, Péter; Hegyi, Péter; Rostás, Ildikó; Garami, András; Szabó, Imre; Solymár, Margit; Pétervári, Erika; Czimmer, József; Márta, Katalin; Mikó, Alexandra; Füredi, Nóra; Párniczky, Andrea; Zsiborás, Csaba; Balaskó, Márta

    2016-01-01

    Background Obesity is one of the major public health challenges worldwide. It involves numerous endocrine disorders as etiological factors or as complications. Previous studies strongly suggested the involvement of the hypothalamic-pituitary-adrenal (HPA) axis activity in obesity, however, to date, no consistent trend in obesity-associated alterations of the HPA axis has been identified. Aging has been demonstrated to aggravate obesity and to induce abnormalities of the HPA axis. Thus, the question arises whether obesity is correlated with peripheral indicators of HPA function in adult populations. Objectives We aimed to meta-analyze literature data on peripheral cortisol levels as indicators of HPA activity in obesity during aging, in order to identify possible explanations for previous contradictory findings and to suggest new approaches for future clinical studies. Data Sources 3,596 records were identified through searching of PubMed, Embase and Cochrane Library Database. Altogether 26 articles were suitable for analyses. Study Eligibility Criteria Empirical research papers were eligible provided that they reported data of healthy adult individuals, included body mass index (BMI) and measured at least one relevant peripheral cortisol parameter (i.e., either morning blood cortisol or 24-h urinary free cortisol). Statistical Methods We used random effect models in each of the meta-analyses calculating with the DerSimonian and Laird weighting methods. I-squared indicator and Q test were performed to assess heterogeneity. Meta-regression was applied to explore the effect of BMI and age on morning blood and urinary free cortisol levels. To assess publication bias Egger’s test was used. Results Obesity did not show any correlation with the studied peripheral cortisol values. On the other hand, peripheral cortisol levels declined with aging within the obese, but not in the non-obese groups. Conclusions Our analysis demonstrated that obesity or healthy aging does not

  4. Fun, Flow, and Fitness: Opinions for Making More Effective Active Videogames.

    PubMed

    Maloney, Ann E; Mellecker, Robin; Buday, Richard; Gao, Zan; Hinkley, Trina; Esparza, Laura; Alexander, Shirley

    2015-02-01

    Despite active videogames' popularity and ability to increase a player's energy expenditure, research indicates their use sharply declines over time, which limits their utility in promoting physical activity. A frequent criticism is that a player's interest is quickly exhausted. At the preconference of the International Society of Behavioral Nutrition and Physical Activity 2014, a group of investigators and videogame developers gathered to share lessons learned from using serious videogames in health behavior change and offer insight to guide future efforts.

  5. Fun, Flow, and Fitness: Opinions for Making More Effective Active Videogames

    PubMed Central

    Mellecker, Robin; Buday, Richard; Gao, Zan; Hinkley, Trina; Esparza, Laura; Alexander, Shirley

    2015-01-01

    Abstract Despite active videogames' popularity and ability to increase a player's energy expenditure, research indicates their use sharply declines over time, which limits their utility in promoting physical activity. A frequent criticism is that a player's interest is quickly exhausted. At the preconference of the International Society of Behavioral Nutrition and Physical Activity 2014, a group of investigators and videogame developers gathered to share lessons learned from using serious videogames in health behavior change and offer insight to guide future efforts. PMID:26181681

  6. Neurocognitive decline in HIV patients is associated with ongoing T-cell activation in the cerebrospinal fluid

    PubMed Central

    Grauer, Oliver M; Reichelt, Doris; Grüneberg, Ute; Lohmann, Hubertus; Schneider-Hohendorf, Tilman; Schulte-Mecklenbeck, Andreas; Gross, Catharina C; Meuth, Sven G; Wiendl, Heinz; Husstedt, Ingo W

    2015-01-01

    Objective HIV-associated neurocognitive disorders (HAND) remain a challenge despite combination antiretroviral therapy (cART). Immune cell activation has been implicated to play a major role in the development of HAND. Methods In this study, we used multicolor flow cytometry on peripheral blood (PB) and cerebrospinal fluid (CSF) samples to determine the expression of HLA-DR and programmed death-1 (PD-1) on CD4+ and CD8+ T cells in patients with chronic HIV infection. Expression levels were correlated with HI virus load in PB and CSF, classification of HAND and severity of magnetic resonance imaging (MRI) signal abnormalities. Results In a cohort of 86 HIV patients we found that the grade of neurocognitive impairment and the severity of MRI signal abnormalities correlated with decreasing CD4/CD8-ratios and increased frequencies of HLA-DR expressing CD4+ and CD8+ T cells reaching the highest values in the CSF samples. Importantly, HLA-DR upregulation was still detectable in virologically suppressed HIV patients. Further, T-cell subpopulation analysis of 40 HIV patients showed a significant shift from naïve to effector memory (EM) T cells that was negatively correlated with the grade of neurocognitive impairment in the PB samples. Moreover, PD-1 was significantly increased on CD4+ memory T cells with highest levels on EM T cells in HIV patients with mild or severe neurocognitive alterations. Interpretation The CD4/CD8 ratio, the proportion of EM to naïve T cells and the immune activation profile of CD4+ and CD8+ T cells in PB and CSF might be useful parameters to monitor the efficacy of cART and to identify HIV patients at risk of further neurocognitive deterioration. PMID:26401512

  7. Ionospheric response to CIR-induced recurrent geomagnetic activity during the declining phase of solar cycle 23

    NASA Astrophysics Data System (ADS)

    Chen, Yanhong; Wang, Wenbin; Burns, Alan G.; Liu, Siqing; Gong, Jiancun; Yue, Xinan; Jiang, Guoying; Coster, Anthea

    2015-02-01

    This paper presents an epoch analysis of global ionosphere responses to recurrent geomagnetic activity during 79 corotating interaction region (CIR) events from 2004 to 2009. The data used were GPS total electron content (TEC) data from the Madrigal Database at the Massachusetts Institute of Technology Haystack Observatory and the electron density (Ne) data obtained from CHAllenging Minisatellite Payload (CHAMP) observations. The results show that global ionosphere responses to CIR events have some common features. In high and middle latitudes, the total electron content (TEC) showed a significant positive response (increased electron densities) in the first epoch day. A negative TEC response occurred at high latitudes of the American sector following the positive response. The CHAMP Ne showed a daytime positive response in all latitudes and a nighttime negative response in the subauroral region. These negative TEC and Ne responses were found to be related to thermospheric composition (O/N2) changes during the storms. At all latitudes, the maximum of the TEC positive effect always occurred at 2-6 h after the CIR starting during local daytime and 10-18 h later for the CIR onset during local nighttime. Case studies indicate that the TEC and Ne positive response had a strong dependence on the southward component (Bz) of the interplanetary magnetic field and solar wind speed. This suggests that penetration electric fields that were associated with changes in solar winds might play a significant role in the positive ionospheric response to storms. During the recovery time of the CIR-produced geomagnetic activity, the TEC positive disturbance at low latitudes sometimes could last for 2-4 days, whereas at middle to high latitudes the disturbance lasted only for 1 day in most cases. A comparison of the ionospheric responses between the American, European and Asian sectors shows that the ionosphere response in the North American sector was stronger than that in the other

  8. Age-related decline of autocrine pituitary adenylate cyclase-activating polypeptide impairs angiogenic capacity of rat cerebromicrovascular endothelial cells.

    PubMed

    Banki, Eszter; Sosnowska, Danuta; Tucsek, Zsuzsanna; Gautam, Tripti; Toth, Peter; Tarantini, Stefano; Tamas, Andrea; Helyes, Zsuzsanna; Reglodi, Dora; Sonntag, William E; Csiszar, Anna; Ungvari, Zoltan

    2015-06-01

    Aging impairs angiogenic capacity of cerebromicrovascular endothelial cells (CMVECs) promoting microvascular rarefaction, but the underlying mechanisms remain elusive. PACAP is an evolutionarily conserved neuropeptide secreted by endothelial cells and neurons, which confers important antiaging effects. To test the hypothesis that age-related changes in autocrine PACAP signaling contributes to dysregulation of endothelial angiogenic capacity, primary CMVECs were isolated from 3-month-old (young) and 24-month-old (aged) Fischer 344 x Brown Norway rats. In aged CMVECs, expression of PACAP was decreased, which was associated with impaired capacity to form capillary-like structures, impaired adhesiveness to collagen (assessed using electric cell-substrate impedance sensing [ECIS] technology), and increased apoptosis (caspase3 activity) when compared with young cells. Overexpression of PACAP in aged CMVECs resulted in increased formation of capillary-like structures, whereas it did not affect cell adhesion. Treatment with recombinant PACAP also significantly increased endothelial tube formation and inhibited apoptosis in aged CMVECs. In young CMVECs shRNA knockdown of autocrine PACAP expression significantly impaired tube formation capacity, mimicking the aging phenotype. Cellular and mitochondrial reactive oxygen species production (dihydroethidium and MitoSox fluorescence, respectively) were increased in aged CMVECs and were unaffected by PACAP. Collectively, PACAP exerts proangiogenic effects and age-related dysregulation of autocrine PACAP signaling may contribute to impaired angiogenic capacity of CMVECs in aging.

  9. Age-Related Decline of Autocrine Pituitary Adenylate Cyclase-Activating Polypeptide Impairs Angiogenic Capacity of Rat Cerebromicrovascular Endothelial Cells

    PubMed Central

    Banki, Eszter; Sosnowska, Danuta; Tucsek, Zsuzsanna; Gautam, Tripti; Toth, Peter; Tarantini, Stefano; Tamas, Andrea; Helyes, Zsuzsanna; Reglodi, Dora; Sonntag, William E.; Csiszar, Anna

    2015-01-01

    Aging impairs angiogenic capacity of cerebromicrovascular endothelial cells (CMVECs) promoting microvascular rarefaction, but the underlying mechanisms remain elusive. PACAP is an evolutionarily conserved neuropeptide secreted by endothelial cells and neurons, which confers important antiaging effects. To test the hypothesis that age-related changes in autocrine PACAP signaling contributes to dysregulation of endothelial angiogenic capacity, primary CMVECs were isolated from 3-month-old (young) and 24-month-old (aged) Fischer 344 x Brown Norway rats. In aged CMVECs, expression of PACAP was decreased, which was associated with impaired capacity to form capillary-like structures, impaired adhesiveness to collagen (assessed using electric cell-substrate impedance sensing [ECIS] technology), and increased apoptosis (caspase3 activity) when compared with young cells. Overexpression of PACAP in aged CMVECs resulted in increased formation of capillary-like structures, whereas it did not affect cell adhesion. Treatment with recombinant PACAP also significantly increased endothelial tube formation and inhibited apoptosis in aged CMVECs. In young CMVECs shRNA knockdown of autocrine PACAP expression significantly impaired tube formation capacity, mimicking the aging phenotype. Cellular and mitochondrial reactive oxygen species production (dihydroethidium and MitoSox fluorescence, respectively) were increased in aged CMVECs and were unaffected by PACAP. Collectively, PACAP exerts proangiogenic effects and age-related dysregulation of autocrine PACAP signaling may contribute to impaired angiogenic capacity of CMVECs in aging. PMID:25136000

  10. South Korean Students, Hit Hard by Currency Decline, Opt to Stay Home

    ERIC Educational Resources Information Center

    McNeill, David

    2009-01-01

    It is too early to predict enrollment numbers for international students in the United States this fall, but universities in Asia are already seeing big declines among South Koreans studying abroad. The value of South Korea's currency has dropped sharply in recent months, almost doubling the cost of living abroad for South Korean students and…

  11. Age-related neurogenesis decline in the subventricular zone is associated with specific cell cycle regulation changes in activated neural stem cells

    PubMed Central

    Daynac, Mathieu; Morizur, Lise; Chicheportiche, Alexandra; Mouthon, Marc-André; Boussin, François D.

    2016-01-01

    Although neural stem cells (NSCs) sustain continuous neurogenesis throughout the adult lifespan of mammals, they progressively exhibit proliferation defects that contribute to a sharp reduction in subventricular neurogenesis during aging. However, little is known regarding the early age-related events in neurogenic niches. Using a fluorescence-activated cell sorting technique that allows for the prospective purification of the main neurogenic populations from the subventricular zone (SVZ), we demonstrated an early decline in adult neurogenesis with a dramatic loss of progenitor cells in 4 month-old young adult mice. Whereas the activated and quiescent NSC pools remained stable up to 12 months, the proliferative status of activated NSCs was already altered by 6 months, with an overall extension of the cell cycle resulting from a specific lengthening of G1. Whole genome analysis of activated NSCs from 2- and 6-month-old mice further revealed distinct transcriptomic and molecular signatures, as well as a modulation of the TGFβ signalling pathway. Our microarray study constitutes a cogent identification of new molecular players and signalling pathways regulating adult neurogenesis and its early modifications. PMID:26893147

  12. Computer Simulation for the Crossing Time in a Diploid, Asymmetric, Sharply-Peaked Landscape in the Infinite Population Limit

    NASA Astrophysics Data System (ADS)

    Gill, Wonpyong

    2013-12-01

    This study calculated the crossing time in the diploid mutation-selection model in an infinite population limit for various dominance parameters, h, and selective advantages, by switching on a diploid, asymmetric, sharply-peaked landscape, from an initial state which is the steady state in a diploid, sharply-peaked landscape. The crossing time for h < 1 was found to diverge at the critical fitness parameter, which increased with increasing selective advantage and decreased with increasing sequence length. When the sequence length was increased with a fixed extension parameter, there was no crossing time for h < 1 when the sequence length was longer than the critical sequence length, which increased with increasing selective advantage. The crossing time for h ≤ 1 was found to be an exponentially increasing function of the sequence length, and the crossing time for h > 1 became saturated at a long sequence length. The crossing time decreased with increasing selective advantage, mainly because the larger selective advantage caused the increase in relative density of the reversal allele to grow exponentially at an earlier time.

  13. Diagnosing School Decline

    ERIC Educational Resources Information Center

    Duke, Daniel L.

    2008-01-01

    One of the most important strategies for stopping school decline is recognizing its signs early on and promptly applying appropriate interventions. In this article, the author identifies 11 indicators of school decline that are associated with inadequate and inappropriate responses to the challenges of budget cuts, state and federal mandates, loss…

  14. Declining Enrollment. Research Report.

    ERIC Educational Resources Information Center

    National School Boards Association, Washington, DC.

    Population growth in the United States has declined since the early 1970s. As a result of the lower birth rate and changing migration patterns, approximately one-third of the school districts in the country have experienced some drop in enrollment. Smaller districts are the hardest hit by enrollment decline, since they are less able to absorb the…

  15. Compensatory responses to age-related decline in odor quality acuity: cholinergic neuromodulation and olfactory enrichment.

    PubMed

    Mandairon, Nathalie; Peace, Shane T; Boudadi, Karim; Boxhorn, Christine E; Narla, Venkata Anupama; Suffis, Sara D; Cleland, Thomas A

    2011-12-01

    The perceptual differentiation of odors can be measured behaviorally using generalization gradients. The steepness of these gradients defines a form of olfactory acuity for odor quality that depends on neural circuitry within the olfactory bulb and is regulated by cholinergic activity therein as well as by associative learning. Using this system as a reduced model for age-related cognitive decline, we show that aged mice, while maintaining almost the same baseline behavioral performance as younger mice, are insensitive to the effects of acutely elevated acetylcholine, which sharpens generalization gradients in young adult mice. Moreover, older mice exhibit evidence of chronically elevated acetylcholine levels in the olfactory bulb, suggesting that their insensitivity to further elevated levels of acetylcholine may arise because the maximum capacity of the system to respond to acetylcholine has already been reached. We propose a model in which an underlying, age-related, progressive deficit is mitigated by a compensatory cholinergic feedback loop that acts to retard the behavioral effects of what would otherwise be a substantial age-related decline in olfactory plasticity. We also treated mice with 10-day regimens of olfactory environmental enrichment and/or repeated systemic injections of the acetylcholinesterase inhibitor physostigmine. Each treatment alone sharpened odor quality acuity, but administering both treatments together had no greater effect than either alone. Age was not a significant main effect in this study, suggesting that some capacity for acetylcholine-dependent plasticity is still present in aged mice despite their sharply reduced ability to respond to acute increases in acetylcholine levels. These results suggest a dynamical framework for understanding age-related decline in neural circuit processing in which the direct effects of aging can be mitigated, at least temporarily, by systemic compensatory responses. In particular, a decline in

  16. Continuous Aerobic Training in Individualized Intensity Avoids Spontaneous Physical Activity Decline and Improves MCT1 Expression in Oxidative Muscle of Swimming Rats

    PubMed Central

    Scariot, Pedro P. M.; Manchado-Gobatto, Fúlvia de Barros; Torsoni, Adriana S.; dos Reis, Ivan G. M.; Beck, Wladimir R.; Gobatto, Claudio A.

    2016-01-01

    Although aerobic training has been shown to affect the lactate transport of skeletal muscle, there is no information concerning the effect of continuous aerobic training on spontaneous physical activity (SPA). Because every movement in daily life (i.e., SPA) is generated by skeletal muscle, we think that it is possible that an improvement of SPA could affect the physiological properties of muscle with regard to lactate transport. The aim of this study was to evaluate the effect of 12 weeks of continuous aerobic training in individualized intensity on SPA of rats and their gene expressions of monocarboxylate transporters (MCT) 1 and 4 in soleus (oxidative) and white gastrocnemius (glycolytic) muscles. We also analyzed the effect of continuous aerobic training on aerobic and anaerobic parameters using the lactate minimum test (LMT). Sixty-day-old rats were randomly divided into three groups: a baseline group in which rats were evaluated prior to initiation of the study; a control group (Co) in which rats were kept without any treatment during 12 weeks; and a chronic exercise group (Tr) in which rats swam for 40 min/day, 5 days/week at 80% of anaerobic threshold during 12 weeks. After the experimental period, SPA of rats was measured using a gravimetric method. Rats had their expression of MCTs determined by RT-PCR analysis. In essence, aerobic training is effective in maintaining SPA, but did not prevent the decline of aerobic capacity and anaerobic performance, leading us to propose that the decline of SPA is not fully attributed to a deterioration of physical properties. Changes in SPA were concomitant with changes in MCT1 expression in the soleus muscle of trained rats, suggestive of an additional adaptive response toward increased lactate clearance. This result is in line with our observation showing a better equilibrium on lactate production-remotion during the continuous exercise (LMT). We propose an approach to combat the decline of SPA of rats in their home

  17. Decline of tactile acuity in aging: a study of body site, blood flow, and lifetime habits of smoking and physical activity.

    PubMed

    Stevens, Joseph C; Alvarez-Reeves, Marty; Dipietro, Loretta; Mack, Gary W; Green, Barry G

    2003-01-01

    Tactile acuity of 60 older subjects (> or = 65 years) and 19 younger subjects (18-28 years) was assessed by two-point gap thresholds at the upper and lower surfaces of the forefinger, at the upper and lower surfaces of the feet, and at the volar surface of the forearm. The older subjects were assigned to one of four groups of 15 subjects each, depending on reported lifetime habits of physical activity and smoking: (1) active smokers, (2) active nonsmokers, (3) inactive smokers, and (4) inactive nonsmokers. Peripheral blood flow was assessed at the forefinger, foot, and forearm by means of laser-Doppler imaging and skin temperature recordings, under resting conditions and during and after a 5-min exposure to mild cooling (28 degrees C). Consistent with previous studies, tactile acuity thresholds in the foot and finger averaged about 80% higher in the older subjects than in the younger subjects, but only about 22% higher in the forearm. Although the upper surface of the fingertip was more sensitive than the lower surface in both younger and older subjects, the age-related decline in tactile acuity was nearly identical on both sides of the finger and foot. The latter finding refutes the hypothesis that the larger effect of aging in the extremities results from greater physical wear and tear on the contact surfaces of the hands and feet. Self-reported lifetime histories of physical activity and smoking were not significantly associated with measures of cutaneous blood flow or tactile thresholds. Possible reasons for this lack of association are discussed, including the inherent limitations of testing only healthy older subjects, and the concept of "successful aging".

  18. N-acetylcysteine attenuates the decline in muscle Na+,K+-pump activity and delays fatigue during prolonged exercise in humans

    PubMed Central

    McKenna, Michael J; Medved, Ivan; Goodman, Craig A; Brown, Malcolm J; Bjorksten, Andrew R; Murphy, Kate T; Petersen, Aaron C; Sostaric, Simon; Gong, Xiaofei

    2006-01-01

    Reactive oxygen species (ROS) have been linked with both depressed Na+,K+-pump activity and skeletal muscle fatigue. This study investigated N-acetylcysteine (NAC) effects on muscle Na+,K+-pump activity and potassium (K+) regulation during prolonged, submaximal endurance exercise. Eight well-trained subjects participated in a double-blind, randomised, crossover design, receiving either NAC or saline (CON) intravenous infusion at 125 mg kg−1 h−1 for 15 min, then 25 mg kg−1 h−1 for 20 min prior to and throughout exercise. Subjects cycled for 45 min at 71% V˙O2peak, then continued at 92% V˙O2peak until fatigue. Vastus lateralis muscle biopsies were taken before exercise, at 45 min and fatigue and analysed for maximal in vitro Na+,K+-pump activity (K+-stimulated 3-O-methyfluorescein phosphatase; 3-O-MFPase). Arterialized venous blood was sampled throughout exercise and analysed for plasma K+ and other electrolytes. Time to fatigue at 92% V˙O2peak was reproducible in preliminary trials (c.v. 5.6 ± 0.6%) and was prolonged with NAC by 23.8 ± 8.3% (NAC 6.3 ± 0.5 versus CON 5.2 ± 0.6 min, P < 0.05). Maximal 3-O-MFPase activity decreased from rest by 21.6 ± 2.8% at 45 min and by 23.9 ± 2.3% at fatigue (P < 0.05). NAC attenuated the percentage decline in maximal 3-O-MFPase activity (%Δactivity) at 45 min (P < 0.05) but not at fatigue. When expressed relative to work done, the %Δactivity-to-work ratio was attenuated by NAC at 45 min and fatigue (P < 0.005). The rise in plasma [K+] during exercise and the Δ[K+]-to-work ratio at fatigue were attenuated by NAC (P < 0.05). These results confirm that the antioxidant NAC attenuates muscle fatigue, in part via improved K+ regulation, and point to a role for ROS in muscle fatigue. PMID:16840514

  19. Age-related changes in the bimanual advantage and in brain oscillatory activity during tapping movements suggest a decline in processing sensory reafference.

    PubMed

    Sallard, Etienne; Spierer, Lucas; Ludwig, Catherine; Deiber, Marie-Pierre; Barral, Jérôme

    2014-02-01

    Deficits in the processing of sensory reafferences have been suggested as accounting for age-related decline in motor coordination. Whether sensory reafferences are accurately processed can be assessed based on the bimanual advantage in tapping: because of tapping with an additional hand increases kinesthetic reafferences, bimanual tapping is characterized by a reduced inter-tap interval variability than unimanual tapping. A suppression of the bimanual advantage would thus indicate a deficit in sensory reafference. We tested whether elderly indeed show a reduced bimanual advantage by measuring unimanual (UM) and bimanual (BM) self-paced tapping performance in groups of young (n = 29) and old (n = 27) healthy adults. Electroencephalogram was recorded to assess the underlying patterns of oscillatory activity, a neurophysiological mechanism advanced to support the integration of sensory reafferences. Behaviorally, there was a significant interaction between the factors tapping condition and age group at the level of the inter-tap interval variability, driven by a lower variability in BM than UM tapping in the young, but not in the elderly group. This result indicates that in self-paced tapping, the bimanual advantage is absent in elderly. Electrophysiological results revealed an interaction between tapping condition and age group on low beta band (14-20 Hz) activity. Beta activity varied depending on the tapping condition in the elderly but not in the young group. Source estimations localized this effect within left superior parietal and left occipital areas. We interpret our results in terms of engagement of different mechanisms in the elderly depending on the tapping mode: a 'kinesthetic' mechanism for UM and a 'visual imagery' mechanism for BM tapping movement.

  20. Forest decline from air pollution

    SciTech Connect

    Hileman, B.

    1984-01-01

    Scientists in West Germany and the USA are involved in intensive efforts to ascertain the cause or causes of the declines in their forests. Ongoing research was discussed at an October 1983 symposium on air pollution and forest productivity, held in Washington, D.C., and sponsored by the Izaak Walton League of America and Pennsylvania State University. The dieback of spruce in the Northeast is relatively well-known. It was revealed at the symposium, however, that forests in other areas of the U.S. may be showing signs of stress and damage and that species other than spruce are affected. Samuel B. McLaughlin of Oak Ridge National Laboratory (ORNL) pointed out that red spruce, shortleaf pine, hickory, yellow birch, pitch pine, hemlock, and Fraser fir are declining in East Tennessee. He noted that these decline together with those in New England suggest that decreased productivity in several tree species has been occurring over a broad scale during the past two decades. One commonly held view is that acid deposition is causing the decline of forests in both Europe and the U.S. At the symposium, a number of different opinions about possible causes were expressed, ranging from drought to ozone to combinations of pollutants, including acid deposition, ozone and trace metals. Possible causes that were not subjects of active inquiry were disease and insects. Most researchers in the field believe there is little evidence that one of these is the primary damaging agent.

  1. Potential output and the recent productivity decline

    SciTech Connect

    Tatom, J.A.

    1982-01-01

    Recent revisions in the measures of the nation's output and capital stock, as well as minor changes in procedures, have altered the Federal Reserve Bank of St. Louis' measures of potential output. The major conclusions of earlier Bank studies, however, have been unaffected by these changes. In particular, the growth of potential output has been sharply reduced by the 1973 to 1974 and 1979 to 1980 energy shocks and subsequent adjustments in the desired capital intensity of production. These effects have been confirmed by the re-estimation of earlier production function coefficients, and, more important, the confirmation of the prior empirical estimates in the latest round of energy price increases. The decline in the growth of potential output since 1973 has, in recent years, been acknowledged by the Council of Economic Advisers, (CEA), but through a trend reduction rather than through sharp temporary declines in 1974 to 1975 and 1979 to 1980 as implied here. Nonetheless, the level of potential output estimated by the CEA in recent years is little different from this Bank's estimate. The slowing in potential output masks a sharper reduction in the growth of productivity in recent years. A detailed analysis of productivity developments shows a marked deterioration in growth relative to past trends. In the measurement of potential output, this deterioration has been partially offset by a more rapid growth of both potential and actual employment. 17 references, 5 figures, 6 tables.

  2. Declining fertility in Nepal.

    PubMed

    Das Dangol, B; Retherford, R D; Thapa, S

    1997-03-01

    This article relies on data from the 1991 Nepal Fertility, Family Planning, and Health Survey (NFFPHS) and the 1996 Nepal Living Standards Survey (NLSS) to assess trends in fertility in Nepal. The NFFPHS shows heaping at ages 5, 8, 10, and 12 years and a larger proportion of infants. The NLSS shows a different pattern of misreporting of youth and a stronger but similar pattern of age heaping as the NFFPHS for adults. Children ever born by maternal age indicates a degree of completeness and the deletion by older women of deceased children and married children living outside the household. Findings suggest less complete reporting in the NLSS. Age-specific fertility rates are calculated based on birth histories (BH) and the own-children (OC) method based on life tables. Findings indicate that BH and OC estimates of the cumulative fertility rate (CFR) derived from the NLSS and the NFFPHS were comparable for estimating trends in the total fertility rate (TFR). The trends from the two data sets overlapped fairly well during 1983-89. Fertility trends by single years of age showed considerably annual fluctuations due to age misreporting. The CFR and TFR for aggregated time periods showed little or no decline for the earlier 5-year period, a steeper decline in the second period, and variations in trends by data set for the third period from 1983 to 1989. One curve showed no decline and the other showed fertility decline. Fitting a straight line to the trend for 1977-91 shows that CFR declined by 1.61 children from 5.29 children in 1977 to 3.68 children in 1991. TFR declined by 1.90 children from 6.68 children in 1977 to 4.78 children in 1991. The author cautions that the point of fertility decline was not determined exactly, but data suggest that decline occurred around 1980, and the rate was fast thereafter. TFR declined by 2.70 children in urban areas and 1.83 children in rural areas.

  3. SENESCENCE-ASSOCIATED DECLINE IN HEPATIC PEROXISOMAL ENZYME ACTIVITIES CORRESPONDS WITH DIMINISHED LEVELS OF RETINOID X RECEPTOR ALPHA, BUT NOT PEROXISOME PROLIFERATOR-ACTIVATED RECEPTOR ALPHA1

    EPA Science Inventory

    Abstract

    Aging is associated with alterations in hepatic peroxisomal metabolism and susceptibility to hepatocarcinogenecity produced by agonists of peroxisome proliferator-activated receptor alpha (PPARa). Mechanisms involved in these effects are not well understood. Howev...

  4. Longitudinal decline of lower extremity muscle power in healthy and mobility-limited older adults: influence of muscle mass, strength, composition, neuromuscular activation and single fiber contractile properties

    PubMed Central

    Reid, Kieran F.; Pasha, Evan; Doros, Gheorghe; Clark, David J.; Patten, Carolynn; Phillips, Edward M.; Frontera, Walter R.; Fielding, Roger A.

    2013-01-01

    Purpose This longitudinal study examined the major physiological mechanisms that determine the age-related loss of lower extremity muscle power in two distinct groups of older humans. We hypothesized that after ~ 3 years of follow-up, mobility-limited older adults (mean age: 77.2 ± 4, n = 22, 12 females) would have significantly greater reductions in leg extensor muscle power compared to healthy older adults (74.1 ± 4, n = 26, 12 females). Methods Mid-thigh muscle size and composition were assessed using computed tomography. Neuromuscular activation was quantified using surface electromyography and vastus lateralis single muscle fibers were studied to evaluate intrinsic muscle contractile properties. Results At follow-up, the overall magnitude of muscle power loss was similar between groups: mobility-limited: −8.5% vs. healthy older: −8.8%, P > 0.8. Mobility-limited elders had significant reductions in muscle size (−3.8%, P< 0.01) and strength (−5.9%, P< 0.02), however, these parameters were preserved in healthy older (P ≥ 0.7). Neuromuscular activation declined significantly within healthy older but not in mobility-limited participants. Within both groups, the cross sectional areas of type I and type IIA muscle fibers were preserved while substantial increases in single fiber peak force ( > 30%), peak power (> 200%) and unloaded shortening velocity (>50%) were elicited at follow-up. Conclusion Different physiological mechanisms contribute to the loss of lower extremity muscle power in healthy older and mobility-limited older adults. Neuromuscular changes may be the critical early determinant of muscle power deficits with aging. In response to major whole muscle decrements, major compensatory mechanisms occur within the contractile properties of surviving single muscle fibers in an attempt to restore overall muscle power and function with advancing age. PMID:24122149

  5. ROS-mediated decline in maximum Ca2+-activated force in rat skeletal muscle fibers following in vitro and in vivo stimulation.

    PubMed

    Dutka, Travis L; Verburg, Esther; Larkins, Noni; Hortemo, Kristin H; Lunde, Per K; Sejersted, Ole M; Lamb, Graham D

    2012-01-01

    We hypothesised that normal skeletal muscle stimulated intensely either in vitro or in situ would exhibit reactive oxygen species (ROS)-mediated contractile apparatus changes common to many pathophysiological conditions. Isolated soleus (SOL) and extensor digitorum longus (EDL) muscles of the rat were bubbled with 95% O(2) and stimulated in vitro at 31°C to give isometric tetani (50 Hz for 0.5 s every 2 s) until maximum force declined to ≤30%. Skinned superficial slow-twitch fibers from the SOL muscles displayed a large reduction (∼41%) in maximum Ca(2+)-activated specific force (F(max)), with Ca(2+)-sensitivity unchanged. Fibers from EDL muscles were less affected. The decrease in F(max) in SOL fibers was evidently due to oxidation effects on cysteine residues because it was reversed if the reducing agent DTT was applied prior to activating the fiber. The GSH:GSSG ratio was ∼3-fold lower in the cytoplasm of superficial fibers from stimulated muscle compared to control, confirming increased oxidant levels. The presence of Tempol and L-NAME during in vitro stimulation prevented reduction in F(max). Skinned fibers from SOL muscles stimulated in vivo at 37°C with intact blood supply also displayed reduction in F(max), though to a much smaller extent (∼12%). Thus, fibers from muscles stimulated even with putatively adequate O(2) supply display a reversible oxidation-induced decrease in F(max) without change in Ca(2+)-sensitivity, consistent with action of peroxynitrite (or possibly superoxide) on cysteine residues of the contractile apparatus. Significantly, the changes closely resemble the contractile deficits observed in a range of pathophysiological conditions. These findings highlight how readily muscle experiences ROS-related deficits, and also point to potential difficulties when defining muscle performance and fatigue.

  6. Urban Decline and Durable Housing.

    ERIC Educational Resources Information Center

    Glaeser, Edward L.; Gyourko, Joseph

    2005-01-01

    Urban decline is not the mirror image of growth, and durable housing is the primary reason the nature of decline is so different. This paper presents a model of urban decline with durable housing and verifies these implications of the model: (1) city growth rates are skewed so that cities grow more quickly than they decline; (2) urban decline is…

  7. ‘Physical Activity 4 Everyone’ school-based intervention to prevent decline in adolescent physical activity levels: 12 month (mid-intervention) report on a cluster randomised trial

    PubMed Central

    Sutherland, Rachel; Campbell, Elizabeth; Lubans, David R; Morgan, Philip J; Okely, Anthony D; Nathan, Nicole; Wolfenden, Luke; Wiese, Jarrod; Gillham, Karen; Hollis, Jenna; Wiggers, John

    2016-01-01

    Background Adolescence is a recognised period of physical activity decline, particularly among low-income communities. We report the 12-month (midpoint) effects of a 2-year multicomponent physical activity intervention implemented in disadvantaged secondary schools. Methods A cluster randomised trial was undertaken in 10 secondary schools located in disadvantaged areas in New South Wales, Australia. Students in Grade 7 were recruited, with follow-up in Grade 8. The intervention was guided by socioecological theory and included seven physical activity strategies, and six implementation adoption strategies. The primary outcome was mean minutes of moderate-to-vigorous physical activity (MVPA) per day assessed using Actigraph GT3X accelerometers. Outcome data were analysed using repeated measures linear mixed models. Results At baseline, 1150 (93%) students participated in the data collection (mean age 12 years, 48% boys) and 1050 (79%) students participated at 12-month follow-up. By the 12-month follow-up, the six implementation adoption strategies had been used to support schools to deliver four of the seven physical activity elements. There was a significant group-by-time interaction for mean minutes of MVPA per day in favour of the intervention group (adjusted difference between groups at follow-up=3.85 min, 95% CI (0.79 to 6.91), p≤0.01), including significantly more vigorous physical activity (2.45 min, p≤0.01), equating to 27 min more MVPA per week. Summary At 12-month follow-up, the intervention had reduced the decline in physical activity among adolescents from disadvantaged schools. The intervention may assist students to meet physical activity guidelines. PMID:26359346

  8. Declining Resources, Targeted Strategies

    ERIC Educational Resources Information Center

    Levenson, Nathan

    2011-01-01

    As resources shrink, the need to do more with less becomes critical. As a business CEO turned superintendent, this author has seen firsthand that many options exist, but none are fun, easy, or politically rewarding. He contends that the challenge of managing declining resources is not the choice between doing less for children or discovering new…

  9. Declining Black Employment.

    ERIC Educational Resources Information Center

    Vedder, Richard; Gallaway, Lowell

    1993-01-01

    Explores income inequality during declining African-American employment, examines current welfare systems, and suggests ways to improve the economic disadvantages of minority groups. Letting markets work can improve the economic status of African Americans. The present dual African-American economy, a market economy and an entitlement economy, is…

  10. Declining School Enrollments.

    ERIC Educational Resources Information Center

    Fowler, Delbert H.

    Declining enrollment means that school districts must engage in thoughtful, thorough planning to cope with this trend, according to the author. His paper outlines a process for school closing, including ways to involve the community in the decision-making process, thereby reducing the likelihood of community conflict and preserving the school…

  11. [Fertility decline in Spain].

    PubMed

    Arango, J

    1987-01-01

    The historical processes of secular fertility decline in Spain and Portugal are not well understood. Very few microdemographic studies of small geographic regions or particular social strata have been done. A contribution by David Reher to the First Spanish-Portuguese-Italian Historical Demography Conference on the fertility decline in the interior province of Cuenca, Spain, uses the own-children method to analyze changes in marital fertility in the 19th and 20th centuries. Reher discovered a slight fertility decline of perhaps 15% which occurred between the end of the 18th century and 1860-75. The fertility decline did not resume until after the Spanish Civil War, and then it was a very gradual and continuous process. When instead of the total female population, women aged 35-39 were studied, unequivocal signs of fertility control appeared. Conscious fertility control thus appears to have begun among older women limiting rather than spacing births. Reher's analysis by social groups demonstrates that fertility declined first and more rapidly in the nonagricultural and urban populations and among the higher income groups. The fertility decline in Cuenca was certainly not identical to that in most of Spain, but may have been fairly typical of a large part of the interior. Another contribution to the Historical Demography Conference, by Anna Cabre and Isabel Pujadas, analyzes fertility trends and cyclical fluctuations in 20th century Cataluna, arguing that they must be placed in historical perspective if recent changes are to be understood and plausible projections made. Their work demonstrates the value of selecting a relatively homogeneous geographic unit for analysis. The contribution of Margarita Delgado to the conference analyzed interregional fertility differences in contemporary Spain. The high legitimate fertility of the south of Spain is accentuated by high nuptiality rates. In central Spain, the combination of high legitimate fertility rates and low

  12. [Functional decline in older people].

    PubMed

    Wada, Taizo

    2013-10-01

    World Health Organization(WHO) proposed to be used as an index of the health of elderly independence of functioning. Basic activities of daily living (BADL), such as bathing, dressing, toileting, transferring, continence, and feeding are well known as the functioning of the elderly. However, not only BADL, there are a variety of levels, such as the ability to play a social role, intellectual activities and instrumental activities of daily living (IADL), which are components of the Tokyo Metropolitan Institute of Gerontology Index of Competence(TMIG-IC). Functional decline in older people is associated with age, gender, depression, up and go test and manual dexterity. Smoking, body-mass index, and exercise patterns in midlife and late adulthood are predictors of subsequent disability.

  13. A Decline in Solar Cycle Strength

    NASA Astrophysics Data System (ADS)

    Chapman, G. A.; de Toma, G.; Cookson, A.

    2013-12-01

    The strength of solar activity appears to be in decline over the past three solar cycles. The decline is seen in sunspot area, facular/network area and the sunspot number. In addition, cycle 24 has been unusual in that many, if not most, of the bipolar sunspot groups have had only a leader spot with no follower spot. This research was partially supported by grants from NSF and NASA. Corrected spot area from CFDT1 at the San Fernando Observatory

  14. Declines in Teenage Birth Rates, 1991-97: National and State Patterns.

    ERIC Educational Resources Information Center

    Ventura, Stephanie J.; Mathews, T. J.; Curtin, Sally C.

    1998-01-01

    This report presents data on the numbers of teenage births and teenage birth rates for the United States for the period 1950-97 and state-specific birth rates for teenagers for 1991-96. After increasing sharply in the late 1980s, birth rates declined for American teenagers from 1991 through 1997. Rates fell overall by 16% for teenagers aged 15-17…

  15. Trends in the golden state: small-group premiums rise sharply while actuarial values for individual coverage plummet.

    PubMed

    Gabel, Jon; Pickreign, Jeremy; McDevitt, Roland; Whitmore, Heidi; Gandolfo, Laura; Lore, Ryan; Wilson, Katy

    2007-01-01

    Using multiple databases, this paper examines recent trends in the affordability and comprehensiveness of small-group and individual health insurance markets in California. Both became less affordable over the study period. In 2006, a single person age 32-52 earning the median income who purchased individual insurance spent on average 16 percent of income on premiums and out-of-pocket medical expenses. For individual insurance, the share of medical expenses paid by insurance as opposed to patients declined from 2002 to 2006. In the small-group market, premiums rose more than 50 percent from 2003 to 2006, but the proportion of claims paid by insurers for a standardized population remained constant.

  16. Physical fitness is predictive for a decline in the ability to perform instrumental activities of daily living in older adults with intellectual disabilities: Results of the HA-ID study.

    PubMed

    Oppewal, Alyt; Hilgenkamp, Thessa I M; van Wijck, Ruud; Schoufour, Josje D; Evenhuis, Heleen M

    2015-01-01

    The ability to perform instrumental activities of daily living (IADL) is important for one's level of independence. A high incidence of limitations in IADL is seen in older adults with intellectual disabilities (ID), which is an important determinant for the amount of support one needs. The aim of this study was to assess the predictive value of physical fitness for the ability to perform IADL, over a 3-year follow-up period, in 601 older adults with ID. At baseline, an extensive physical fitness assessment was performed. In addition, professional caregivers completed the Lawton IADL scale, both at baseline and at follow-up. The average ability to perform IADL declined significantly over the 3-year follow-up period. A decline in the ability to perform IADL was seen in 44.3% of the participants. The percentage of participants being completely independent in IADL declined from 2.7% to 1.3%. Manual dexterity, balance, comfortable and fast gait speed, muscular endurance, and cardiorespiratory fitness were significant predictors for a decline in IADL after correcting for baseline IADL and personal characteristics (age, gender, level of ID, and Down syndrome). This can be interpreted as representing the predictive validity of the physical tests for a decline in IADL. This study shows that even though older adults with ID experience dependency on others due to cognitive limitations, physical fitness also is an important aspect for IADL, which stresses the importance of using physical fitness tests and physical fitness enhancing programs in the care for older adults with ID.

  17. Problems Associated with Declining National Oil Production

    NASA Astrophysics Data System (ADS)

    Jackson, J. S.

    2009-12-01

    Forecasts of peak oil production have focussed on the global impacts of declining production. Meanwhile, national oil production has declined in 20 countries, leading to local problems that receive little comment outside of the effected regions. Two problems deserve wider recognition: declining state revenues and fuel substitution. Most oil producing countries with large reserves adopted licensing practices that provide significant revenues to the host governments such that oil revenues generate from 40 to 80 percent of total government funds. Typically these governments allocate a fraction of this revenue to their state oil companies, utilizing the remainder for other activities. As oil revenues decline with falling production, host governments face a dilemma: either to increase state oil company budgets in order to stem the decline, or to starve the state oil company while maintaining other government programs. The declining oil revenues in these states can significantly reduce the government's ability to address important national issues. Mexico, Indonesia, and Yemen illustrate this situation in its early phases. Fuel substitution occurs whenever one fuel proves less expensive than another. The substitution of coal for wood in the eighteenth century and oil for coal in the twentieth century are classic examples. China and India appear to be at peak oil production, while their economies generate increasing demand for energy. Both countries are substituting coal and natural gas for oil with attendant environmental impacts. Coal-to-liquids projects are proposed in in both China, which will require significant water resources if they are executed. These examples suggest that forecasting the impact of peak oil at a regional level requires more than an assessment of proven-probable-possible reserves and a forecast of supply-demand scenarios. A range of government responses to declining oil income scenarios must also be considered, together with scenarios describing

  18. Three decades of recurrent declines and recoveries in corals belie ongoing change in fish assemblages

    NASA Astrophysics Data System (ADS)

    Lamy, T.; Galzin, R.; Kulbicki, M.; Lison de Loma, T.; Claudet, J.

    2016-03-01

    Coral reefs are increasingly being altered by a myriad of anthropogenic activities and natural disturbances. Long-term studies offer unique opportunities to understand how multiple and recurrent disturbances can influence coral reef resilience and long-term dynamics. While the long-term dynamics of coral assemblages have been extensively documented, the long-term dynamics of coral reef fish assemblages have received less attention. Here, we describe the changes in fish assemblages on Tiahura reef, Moorea, from 1979 to 2011. During this 33-yr period, Tiahura was exposed to multiple disturbances (crown-of-thorns seastar outbreaks and cyclones) that caused recurrent declines and recoveries of coral cover and changes in the dominant coral genera. These shifts in coral composition were associated with long-term cascading effects on fish assemblages. The composition and trophic structure of fish assemblages continuously shifted without returning to their initial composition, whereas fish species richness remained stable, albeit with a small increase over time. We detected nonlinear responses of fish density when corals were most degraded. When coral cover dropped below 10 % following a severe crown-of-thorns sea star outbreak, the density of most fish trophic groups sharply decreased. Our study shows that historical contingency may potentially be an important but largely underestimated factor explaining the contemporary structure of reef fish assemblages and suggests that temporal stability in their structure and function should not necessarily be the target of management strategies that aim at increasing or maintaining coral reef resilience.

  19. Increasing metabolic rate despite declining body weight in an adult parasitoid wasp.

    PubMed

    Casas, Jérôme; Body, Mélanie; Gutzwiller, Florence; Giron, David; Lazzari, Claudio R; Pincebourde, Sylvain; Richard, Romain; Llandres, Ana L

    2015-08-01

    Metabolic rate is a positive function of body weight, a rule valid for most organisms and the basis of several theories of metabolic ecology. For adult insects, however, the diversity of relationships between body mass and respiration remains unexplained. The aim of this study is to relate the respiratory metabolism of a parasitoid with body weight and foraging activity. We compared the metabolic rate of groups of starving and host-fed females of the parasitoid Eupelmus vuilleti recorded with respirometry for 7days, corresponding to the mean lifetime of starving females and over half of the lifetime of foraging females. The dynamics of carbohydrate, lipid and protein in the body of foraging females were quantified with biochemical techniques. Body mass and all body nutrients declined sharply from the first day onwards. By contrast, the CO2 produced and the O2 consumed increased steadily. Starving females showed the opposite trend, identifying foraging as the reason for the respiration increase of feeding females. Two complementary physiological processes explain the unexpected relationship between increasing metabolic rate and declining body weight. First, host hemolymph is a highly unbalanced food, and the excess nutrients (protein and carbohydrate) need to be voided, partially through excretion and partially through respiration. Second, a foraging young female produces eggs at an increasing rate during the first half of its lifetime, a process that also increases respiration. We posit that the time-varying metabolic rate contributions of the feeding and reproductive processes supplements the contribution of the structural mass and lead to the observed trend. We extend our explanations to other insect groups and discuss the potential for unification using Dynamic Energy Budget theory.

  20. IUSSP activities. Committee on Anthropological Demography. Report: Seminar on Fertility and the Male Life Cycle in the Era of Fertility Decline, Zacatecas, Mexico, 13-16 November 1995.

    PubMed

    Infesta Dominquez, G

    1996-05-01

    This article gives an overview of a conference on Fertility and the Male Life Cycle held in Mexico on November 13-16, 1995. The seminars, organized by anthropological demographers, were based on the view that differences in men's life course events affect how many children are produced, when children are produced, and the kind of support given to children. Little research has focused on male fertility. Two overview papers addressed the issues of men's changing sexual and reproductive intentions as a response to economic changes (Jane Guyer) and theories of male fertility trends in industrialized countries (David Coleman). Other papers were presented on the following topics: changes in male fertility, sexuality and the male life cycle, polygyny and fertility, men's notions of sexuality and reproductive health, masculinity and reproduction, and future research directions. Laurent Toulemon and Evelyne Lapierre-Adamcyk and Katarina Pohl presented papers on gender differences in fertility. Philip Setel presented an analysis of the social construction of parenthood among Coastal Boiken in Papua New Guinea. Paul Miret discussed men's role in the sharp decline in Spanish fertility. Nosa Orobaton contrasted African men's changing roles over the life course. Differences in fertility among polygynous populations in Africa and in China were analyzed by Ann Blanc and Anastasia Gage, and James Lee and Wang Feng. Other papers were prepared by Juan Gillermo Figueroa Perea, John Anarfi and Clara Korkor, Frances L. Goldscheider et al., Benno de Keijzer, and Mario Humberto Ruz, Ondina Fachel Leal and Jandyra M.G. Fachel, and Kamran Asdar Ali. Seminar papers were expected to be published in several collections.

  1. Mobility decline in old age.

    PubMed

    Rantakokko, Merja; Mänty, Minna; Rantanen, Taina

    2013-01-01

    Mobility is important for community independence. With increasing age, underlying pathologies, genetic vulnerabilities, physiological and sensory impairments, and environmental barriers increase the risk for mobility decline. Understanding how mobility declines is paramount to finding ways to promote mobility in old age.

  2. Which older people decline participation in a primary care trial of physical activity and why: insights from a mixed methods approach

    PubMed Central

    2014-01-01

    Background Physical activity is of vital importance to older peoples’ health. Physical activity intervention studies with older people often have low recruitment, yet little is known about non-participants. Methods Patients aged 60–74 years from three UK general practices were invited to participate in a nurse-supported pedometer-based walking intervention. Demographic characteristics of 298 participants and 690 non-participants were compared. Health status and physical activity of 298 participants and 183 non-participants who completed a survey were compared using age, sex adjusted odds ratios (OR) (95% confidence intervals). 15 non-participants were interviewed to explore perceived barriers to participation. Results Recruitment was 30% (298/988). Participants were more likely than non-participants to be female (54% v 47%; p = 0.04) and to live in affluent postcodes (73% v 62% in top quintile; p < 0.001). Participants were more likely than non-participants who completed the survey to have an occupational pension OR 2.06 (1.35-3.13), a limiting longstanding illness OR 1.72 (1.05-2.79) and less likely to report being active OR 0.55 (0.33-0.93) or walking fast OR 0.56 (0.37-0.84). Interviewees supported general practice-based physical activity studies, particularly walking, but barriers to participation included: already sufficiently active, reluctance to walk alone or at night, physical symptoms, depression, time constraints, trial equipment and duration. Conclusion Gender and deprivation differences suggest some selection bias. However, trial participants reported more health problems and lower activity than non-participants who completed the survey, suggesting appropriate trial selection in a general practice population. Non-participant interviewees indicated that shorter interventions, addressing physical symptoms and promoting confidence in pursuing physical activity, might increase trial recruitment and uptake of practice-based physical activity

  3. Only signaling modules that discriminate sharply between stimulatory and nonstimulatory inputs require basal signaling for fast cellular responses

    NASA Astrophysics Data System (ADS)

    Artomov, Mykyta; Kardar, Mehran; Chakraborty, Arup K.

    2010-09-01

    In many types of cells, binding of molecules to their receptors enables cascades of intracellular chemical reactions to take place (signaling). However, a low level of signaling also occurs in most unstimulated cells. Such basal signaling in resting cells can have many functions, one of which is that it is thought to be required for fast cellular responses to external stimuli. A mechanistic understanding of why this is true and which features of cellular signaling networks make basal signaling necessary for fast responses is unknown. We address this issue by obtaining the time required for activation of common types of cell signaling modules with and without basal signaling. Our results show that the absence of basal signaling does not have any dramatic effects on the response time for signaling modules that exhibit a graded response to increasing stimulus levels. In sharp contrast, signaling modules that exhibit sharp dose-response curves which discriminate sensitively between stimuli to which the cell needs to respond and low-grade inputs (or stochastic noise) require basal signaling for fast cellular responses. In such cases, we find that an optimal level of basal signaling balances the requirements for fast cellular responses while minimizing spurious activation without appropriate stimulation.

  4. Growth behavior of additional offspring with a beneficial reversal allele in the asymmetric sharply-peaked landscape in the coupled discrete-time mutation-selection model

    NASA Astrophysics Data System (ADS)

    Gill, Wonpyong

    2013-01-01

    The probability of additional offspring with a beneficial reversal allele for growing to a size NC for a range of population sizes N, sequence lengths L, selective advantages s, and measuring parameters C was calculated for a haploid, asexual population in the coupled discrete-time mutation-selection model in an asymmetric sharply-peaked landscape with a positive selective advantage of the reversal allele over the optimal allele. The growing probability in the stochastic region was inversely proportional to the measuring parameter when C < 1 /Ns, bent when C ≈ 1/ Ns and saturated when C > 1/ Ns. The crossing time and the time dependence of the increase in relative density of the reversal allele in the coupled discrete-time mutation-selection model was approximated using the Wright-Fisher two-allele model with the same selective advantage and corresponding effective mutation rate. The growth behavior of additional offspring with the reversal allele in the asymmetric sharply-peaked landscape in the coupled discrete-time mutation-selection model was controlled by the selective advantage of the reversal allele compared to the optimal allele and could be described by using the Wright-Fisher two-allele model, in spite of there being many other alleles with lower fitness, and in spite of there being two alleles, the optimal and reversal allele, separated by a low-fitness valley with a tunable depth and width.

  5. Slowing of Hippocampal Activity Correlates with Cognitive Decline in Early Onset Alzheimer’s Disease. An MEG Study with Virtual Electrodes

    PubMed Central

    Engels, Marjolein M. A.; Hillebrand, Arjan; van der Flier, Wiesje M.; Stam, Cornelis J.; Scheltens, Philip; van Straaten, Elisabeth C. W.

    2016-01-01

    Pathology in Alzheimer’s disease (AD) starts in the entorhinal cortex and hippocampus. Because of their deep location, activity from these areas is difficult to record with conventional electro- or magnetoencephalography (EEG/MEG). The purpose of this study was to explore hippocampal activity in AD patients and healthy controls using “virtual MEG electrodes”. We used resting-state MEG recordings from 27 early onset AD patients [age 60.6 ± 5.4, 12 females, mini-mental state examination (MMSE) range: 19–28] and 26 cognitively healthy age- and gender-matched controls (age 61.8 ± 5.5, 14 females). Activity was reconstructed using beamformer-based virtual electrodes for 78 cortical regions and 6 hippocampal regions. Group differences in peak frequency and relative power in six frequency bands were identified using permutation testing. For the patients, spearman correlations between the MMSE scores and peak frequency or relative power were calculated. Moreover, receiver operator characteristic curves were plotted to estimate the diagnostic accuracy. We found a lower hippocampal peak frequency in AD compared to controls, which, in the patients, correlated positively with MMSE [r(25) = 0.61; p < 0.01] whereas hippocampal relative theta power correlated negatively with MMSE [r(25) = -0.54; p < 0.01]. Cortical peak frequency was also lower in AD in association areas. Furthermore, cortical peak frequency correlated positively with MMSE [r(25) = 0.43; p < 0.05]. In line with this finding, relative theta power was higher in AD across the cortex, and relative alpha and beta power was lower in more circumscribed areas. The average cortical relative theta power was the best discriminator between AD and controls (sensitivity 82%; specificity 81%). Using beamformer-based virtual electrodes, we were able to detect hippocampal activity in AD. In AD, this hippocampal activity is slowed, and correlates better with cognition than the (slowed) activity in cortical areas. On the

  6. Rate of decline in progressive supranuclear palsy.

    PubMed

    Litvan, Irene; Kong, Maiying

    2014-04-01

    The rate of patients' decline is critical to properly design trials of disease-modifying agents. We prospectively quantified the progression of 27 progressive supranuclear palsy (PSP) patients for at least 1 year to determine the rate of decline of motor, ocular-motor, neuropsychological, and neuropsychiatric features. PSP patients meeting the National Institute of Neurological Disorders and the Society for Progressive Supranuclear Palsy criteria were assessed using the PSP Rating Scale (PSP-RS) and modified UPDRS. The Mini-Mental State Examination (MMSE) and Frontal Assessment Battery assessed cognitive decline, the Neuropsychiatric Inventory assessed behavior, and the modified Schwab and England scale and UPDRS ADL assessed activities of daily living (ADL). The rate of change of each score was calculated as 1-year worsening score. Power and sample sizes were estimated. PSP patients showed a significant yearly decline in total and subtotal scores of the PSP-RS and UPDRS, as well as in MMSE, and UPDRS and Schwab and England ADL scores. In addition, they had significant deterioration of individual item scores reflecting major aspects of the disease (i.e., ocular-motor). The rate of decline reflected in the UPDRS mirrored that of the PSP-RS. The worsening of the ADL score was positively correlated with the PSP-RS progression of falls and ocular-motor subitem scores and with executive dysfunction. PSP patients showed a significant yearly decline in motor, ocular-motor, and ADL functions. Our findings suggest that using more-advanced technology to measure ocular-motor, postural instability, and ADL will be helpful in planning future therapeutic trials.

  7. Evolution of broadly cross-reactive HIV-1-neutralizing activity: therapy-associated decline, positive association with detectable viremia, and partial restoration of B-cell subpopulations.

    PubMed

    Ferreira, Carolina B; Merino-Mansilla, Alberto; Llano, Anuska; Pérez, Ignacio; Crespo, Isabel; Llinas, Laia; Garcia, Felipe; Gatell, Jose M; Yuste, Eloisa; Sanchez-Merino, Victor

    2013-11-01

    Little is known about the stability of HIV-1 cross-neutralizing responses. Taking into account the fact that neutralization breadth has been positively associated with plasma viral load, there is no explanation for the presence of broadly neutralizing responses in a group of patients on treatment with undetectable viremia. In addition, the B-cell profile responsible for broadly cross-neutralizing responses is unknown. Here we studied the evolution of neutralizing responses and the B-cell subpopulation distribution in a group of patients with broadly cross-reactive HIV-1-neutralizing activity. We studied neutralization breadth evolution in a group of six previously identified broadly cross-neutralizing patients and six control patients during a 6-year period with a previously described minipanel of recombinant viruses from five different subtypes. B-cell subpopulation distribution during the study was also determined by multiparametric flow cytometry. Broadly cross-neutralizing activity was transient in four broad cross-neutralizers and stable, up to 4.6 years, in the other two. In four out of five broad cross-neutralizers who initiated treatment, a neutralization breadth loss occurred after viremia had been suppressed for as much as 20 months. B-cell subpopulation analyses revealed a significant increase in the frequency of naive B cells in broadly cross-reactive samples, compared with samples with less neutralization breadth (increased from 44% to 62%). We also observed a significant decrease in tissue-like and activated memory B cells (decreased from 19% to 12% and from 17% to 9%, respectively). Our data suggest that HIV-1 broadly cross-neutralizing activity is variable over time and associated with detectable viremia and partial B-cell restoration.

  8. Growth declines in red spruce

    SciTech Connect

    Zedaker, S.M.; Hyink, D.M.; Smith, D.W.

    1987-01-01

    Over the past two decades second-growth red spruce stands in the Northeast have demonstrated declines in radial increment. Some observers are implicating air pollution as a primary cause of the declines, based on recently acquired increment cores from dominant trees. Various forms of air pollution (O/sub 3/, NO/sub x/, SO/sub 2/, and trace metals) are known to reduce growth and development of tree species, but few studies have provided concrete evidence of regional pollution-caused declines in forest ecosystems. Recently published evidence of a synchronous, consistent, and unprecedented regional decline in red spruce should be weighed against the realization that radial increment in red spruce declines naturally as stands age. Separating anthropogenic stress-caused growth patterns from natural stand dynamics requires an in-depth knowledge of forest growth and yield, tree silvics, and forest ecosystem processes. Detailed analyses of growth by stand characteristics - site index, density, elevation, stand history - will be necessary to implicate air pollution as a primary cause of red spruce decline.

  9. Age-dependent changes of the antioxidant system in rat livers are accompanied by altered MAPK activation and a decline in motor signaling

    PubMed Central

    Yang, Wei; Burkhardt, Britta; Fischer, Luise; Beirow, Maja; Bork, Nadja; Wönne, Eva C.; Wagner, Cornelia; Husen, Bettina; Zeilinger, Katrin; Liu, Liegang; Nussler, Andreas K.

    2015-01-01

    Aging is characterized by a progressive decrease of cellular functions, because cells gradually lose their capacity to respond to injury. Increased oxidative stress is considered to be one of the major contributors to age-related changes in all organs including the liver. Our study has focused on elucidating whether important antioxidative enzymes, the mTOR pathway, and MAPKs exhibit age-dependent changes in the liver of rats during aging. We found an age-dependent increase of GSH in the cytosol and mitochondria. The aged liver showed an increased SOD enzyme activity, while the CAT enzyme activity decreased. HO-1 and NOS-2 gene expression was lower in adult rats, but up-regulated in aged rats. Western blot analysis revealed that SOD1, SOD2, GPx, GR, γ-GCL, and GSS were age-dependent up-regulated, while CAT remained constant. We also demonstrated that the phosphorylation of Akt, JNK, p38, and TSC2Ser1254 decreased while ERK1/2 and TSC2Thr1462 increased age-dependently. Furthermore, our data show that the mTOR pathway seems to be activated in livers of aged rats, and hence stimulating cell proliferation/regeneration, as confirmed by an age-dependent increase of PCNA and p-eIF4ESer209 protein expression. Our data may help to explain the fact that liver cells only proliferate in cases of necessity, like injury and damage. In summary, we have demonstrated that, age-dependent changes of the antioxidant system and stress-related signaling pathways occur in the livers of rats, which may help to better understand organ aging. PMID:27004051

  10. Rapid Functional Decline of Activated and Memory Graft-vs-Host-Reactive T Cells Encountering Host Antigens in the Absence of Inflammation

    PubMed Central

    Li, Hao Wei; Andreola, Giovanna; Carlson, Alicia; Shao, Steven; Lin, Charles; Zhao, Guiling; Sykes, Megan

    2015-01-01

    Inflammation in the priming host environment has critical effects on the graft-vs-host (GVH) responses mediated by naïve donor T cells. However, it is unclear how a quiescent or inflammatory environment impacts the activity of GVH-reactive primed T and memory cells. We show here that GVH-reactive primed donor T cells generated in irradiated recipients had diminished ability compared to naïve T cells to increase donor chimerism when transferred to quiescent mixed allogeneic chimeras. GVH-reactive primed T cells showed marked loss of cytotoxic function and activation and delayed but not decreased proliferation or accumulation in lymphoid tissues when transferred to quiescent mixed chimeras compared to freshly irradiated secondary recipients. Primed CD4 and CD8 T cells provided mutual help to sustain these functions in both subsets. CD8 help for CD4 cells was largely IFN-γ-dependent. Toll-like receptor (TLR) stimulation following transfer of GVH-reactive primed T cells to mixed chimeras restored their cytotoxic effector function and permitted the generation of more effective T cell memory in association with reduced PD-1 expression on CD4 memory cells. Our data indicate that an inflammatory host environment is required for the maintenance of GVH-reactive primed T cell functions and the generation of memory T cells that can rapidly acquire effector functions. These findings have important implications for GVHD and T cell-mediated immunotherapies. PMID:26085679

  11. Rapid Functional Decline of Activated and Memory Graft-versus-Host-Reactive T Cells Encountering Host Antigens in the Absence of Inflammation.

    PubMed

    Li, Hao Wei; Andreola, Giovanna; Carlson, Alicia L; Shao, Steven; Lin, Charles P; Zhao, Guiling; Sykes, Megan

    2015-08-01

    Inflammation in the priming host environment has critical effects on the graft-versus-host (GVH) responses mediated by naive donor T cells. However, it is unclear how a quiescent or inflammatory environment impacts the activity of GVH-reactive primed T and memory cells. We show in this article that GVH-reactive primed donor T cells generated in irradiated recipients had diminished ability compared with naive T cells to increase donor chimerism when transferred to quiescent mixed allogeneic chimeras. GVH-reactive primed T cells showed marked loss of cytotoxic function and activation, and delayed but not decreased proliferation or accumulation in lymphoid tissues when transferred to quiescent mixed chimeras compared with freshly irradiated secondary recipients. Primed CD4 and CD8 T cells provided mutual help to sustain these functions in both subsets. CD8 help for CD4 cells was largely IFN-γ dependent. TLR stimulation after transfer of GVH-reactive primed T cells to mixed chimeras restored their cytotoxic effector function and permitted the generation of more effective T cell memory in association with reduced PD-1 expression on CD4 memory cells. Our data indicate that an inflammatory host environment is required for the maintenance of GVH-reactive primed T cell functions and the generation of memory T cells that can rapidly acquire effector functions. These findings have important implications for graft-versus-host disease and T cell-mediated immunotherapies.

  12. Activation of mTOR signaling leads to orthopedic surgery-induced cognitive decline in mice through β-amyloid accumulation and tau phosphorylation.

    PubMed

    Shen, Wenzhen; Lu, Keliang; Wang, Jiawan; Wu, Anshi; Yue, Yun

    2016-10-01

    Postoperative cognitive dysfunction (POCD) is a serious complication following surgery, however, the mechanism of POCD remains to be elucidated. Previous evidence has revealed that POCD may be associated with the pathogenesis of neurodegenerative processes. The mammalian target of rapamycin (mTOR) signaling pathway has been reported to be crucial in the pathophysiology of neurodegenerative diseases. However, the implications of mTOR in POCD remains to be fully elucidated. In the present study, western blotting and enzyme‑linked immunosorbent assay were used to determine the expression of mTOR and any associated downstream targets; contextual fear conditioning was used to estimate the learning and memory ability of mice. Using an animal model of orthopedic surgery, it was found that surgical injury impaired hippocampal‑dependent memory and enhanced the levels of phosphorylated mTOR at Serine‑2448, phosphorylated 70‑kDa ribosomal protein S6 kinase (p70S6K) at Threonine‑389 with accumulation of β‑amyloid (Aβ) and hyperphosphorylated tau at Serine-396, compared with the control group. Pretreatment with rapamycin, an mTOR inhibitor, restored the abnormal mTOR/p70S6K signaling induced by surgery, attenuated the accumulation of Aβ and reduced the phosphorylation of tau protein. Rapamycin also reversed the surgery‑induced cognitive dysfunction. The results of the present study suggested that the surgical stimulus activated mTOR/p70S6K signaling excessively, and that the inhibition of mTOR signaling with rapamycin may prevent postoperative cognitive deficits, partly through attenuating the accumulation of Aβ and hyperphosphorylation of tau protein.

  13. Catalase and superoxide dismutase activities after heat injury of listeria monocytogenes

    SciTech Connect

    Dallmier, A.W.; Martin, S.E.

    1988-02-01

    Four strains of Listeria monocytogenes were examined for catalase (CA) and superoxide dismutase (SOD) activities. The two strains having the highest CA activities (LCDC and Scott A) also possessed the highest SOD activities. The CA activity of heated cell extracts of all four strains examined decreased sharply between 55 and 60/sup 0/C. SOD was more heat labile than CA. Two L. monocytogenes strains demonstrated a decline in SOD activity after heat treatment at 45/sup 0/C, whereas the other two strains demonstrated a decline at 50/sup 0/C. Sublethal heating of the cells at 55/sup 0/C resulted in increased sensitivity to 5.5% NaCl. Exogenous hydrogen peroxide was added to suspensions of L. monocytogenes; strains producing the highest CA levels showed the greatest H/sub 2/O/sub 2/ resistance.

  14. Growth declines in red spruce

    SciTech Connect

    McLaughlin, S.B. ); Adams, H.S. )

    1987-10-01

    In this letter, the authors take issue with Zedaker, Hyink, and Smith who have indicated that observed red spruce growth declines can be expected based on growth trends for even-aged stands of red spruce as documented in Meyer (1929). Recently, an examination was made of stand stocking levels at 750 sites where red spruce were cored and neither the rate of growth decline nor the extent of mortality were found to be related to stand stocking levels or previous disturbance history. The authors conclude that the Meyer data do not represent an appropriate model for stand dynamics of old-growth, high-elevation stands and no not adequately explain the growth declines observed at many of those sites.

  15. Acetyl-L-carnitine supplementation reverses the age-related decline in carnitine palmitoyltransferase 1 (CPT1) activity in interfibrillar mitochondria without changing the L-carnitine content in the rat heart.

    PubMed

    Gómez, Luis A; Heath, Shi-Hua D; Hagen, Tory M

    2012-01-01

    The aging heart displays a loss of bioenergetic reserve capacity partially mediated through lower fatty acid utilization. We investigated whether the age-related impairment of cardiac fatty acid catabolism occurs, at least partially, through diminished levels of L-carnitine, which would adversely affect carnitine palmitoyltransferase 1 (CPT1), the rate-limiting enzyme for fatty acyl-CoA uptake into mitochondria for β-oxidation. Old (24-28 mos) Fischer 344 rats were fed±acetyl-L-carnitine (ALCAR; 1.5% [w/v]) for up to four weeks prior to sacrifice and isolation of cardiac interfibrillar (IFM) and subsarcolemmal (SSM) mitochondria. IFM displayed a 28% (p<0.05) age-related loss of CPT1 activity, which correlated with a decline (41%, p<0.05) in palmitoyl-CoA-driven state 3 respiration. Interestingly, SSM had preserved enzyme function and efficiently utilized palmitate. Analysis of IFM CPT1 kinetics showed both diminished V(max) and K(m) (60% and 49% respectively, p<0.05) when palmitoyl-CoA was the substrate. However, no age-related changes in enzyme kinetics were evident with respect to L-carnitine. ALCAR supplementation restored CPT1 activity in heart IFM, but not apparently through remediation of L-carnitine levels. Rather, ALCAR influenced enzyme activity over time, potentially by modulating conditions in the aging heart that ultimately affect palmitoyl-CoA binding and CPT1 kinetics.

  16. Functional decline in old age

    PubMed Central

    Hébert, R

    1997-01-01

    Functional decline is a common condition, occurring each year in nearly 12% of Canadians 75 years of age and older. The model of functional health proposed by the World Health Organization (WHO) represents a useful theoretical framework and is the basis for the SMAF (Système de measure de l'autonomie fonctionelle or Functional Autonomy Measurement System), an instrument that measures functional autonomy. The functional decline syndrome, in which functional autonomy is diminished or lost, may present as an acute condition, i.e., a medical emergency for which the patient must be admitted to a geriatric assessment unit. The subacute form is a more insidious condition in which the patient requires comprehensive assessment and a rehabilitation program. A preventive approach based on screening of those at risk and early intervention should prevent or delay the appearance of functional decline or diminish its consequences. Effective strategies for the prevention of or rehabilitation from functional decline will help reduce the incidence of disabilities and the period of dependence near the end of life. These strategies are absolute prerequisites for controlling sociohealth expenses and, most importantly, for allowing people to live independently in old age. PMID:9347774

  17. Impact of Declining Rural Infrastructure.

    ERIC Educational Resources Information Center

    McKenzie, Fiona Haslem

    A study investigated the impact of declining rural community infrastructure on social, environmental, and economic well-being in Western Australia's central wheatbelt. Questionnaires were completed by 398 residents of the central wheatbelt, on-farm interviews were conducted with 68 respondents, and 4 focus groups were held in area towns.…

  18. The rise (and decline?) of biotechnology.

    PubMed

    Kinch, Michael S

    2014-11-01

    Since the 1970s, biotechnology has been a key innovator in drug development. An analysis of FDA-approved therapeutics demonstrates pharmaceutical companies outpace biotechs in terms of new approvals but biotechnology companies are now responsible for earlier-stage activities (patents, INDs or clinical development). The number of biotechnology organizations that contributed to an FDA approval began declining in the 2000s and is at a level not seen since the 1980s. Whereas early biotechnology companies had a decade from first approval until acquisition, the average acquisition of a biotechnology company now occurs months before their first FDA approval. The number of hybrid organizations that arise when pharmaceutical companies acquire biotechnology is likewise declining, raising questions about the sustainability of biotechnology.

  19. Predicting Succession under Conditions of Enrollment Decline.

    ERIC Educational Resources Information Center

    Berger, Michael A.

    1984-01-01

    Using 56 school districts that experienced enrollment declines, this study describes the variables in superintendent succession amidst declining enrollments and locates the strongest predictors of succession. (JW)

  20. Decline of the oil cartel

    SciTech Connect

    Fieleke, N.S.

    1986-07-01

    A review of the development that led to the current decline in oil prices concludes that sharp relative price changes have been a major source of world economic instability for the past 13 years. The results for oil-importing countries have been cycles of inflation and contraction followed by inflation and rapid growth. Some see the recent price decline as an effort by OPEC to regain enough power to bring about an eventual price rise. Although past price and production relationships indicate that OPEC has operated as a cartel, the author sees current efforts to persuade non-OPEC producers to lower their production as an indication of weakness. The Strategic Petroleum Reserve could help the US cope with any future supply disruption. 7 figures, 3 tables.

  1. Cognitive decline in Parkinson disease.

    PubMed

    Aarsland, Dag; Creese, Byron; Politis, Marios; Chaudhuri, K Ray; Ffytche, Dominic H; Weintraub, Daniel; Ballard, Clive

    2017-04-01

    Dementia is a frequent problem encountered in advanced stages of Parkinson disease (PD). In recent years, research has focused on the pre-dementia stages of cognitive impairment in PD, including mild cognitive impairment (MCI). Several longitudinal studies have shown that MCI is a harbinger of dementia in PD, although the course is variable, and stabilization of cognition - or even reversal to normal cognition - is not uncommon. In addition to limbic and cortical spread of Lewy pathology, several other mechanisms are likely to contribute to cognitive decline in PD, and a variety of biomarker studies, some using novel structural and functional imaging techniques, have documented in vivo brain changes associated with cognitive impairment. The evidence consistently suggests that low cerebrospinal fluid levels of amyloid-β42, a marker of comorbid Alzheimer disease (AD), predict future cognitive decline and dementia in PD. Emerging genetic evidence indicates that in addition to the APOE*ε4 allele (an established risk factor for AD), GBA mutations and SCNA mutations and triplications are associated with cognitive decline in PD, whereas the findings are mixed for MAPT polymorphisms. Cognitive enhancing medications have some effect in PD dementia, but no convincing evidence that progression from MCI to dementia can be delayed or prevented is available, although cognitive training has shown promising results.

  2. Sharply curved turn around duct flow predictions using spectral partitioning of the turbulent kinetic energy and a pressure modified wall law

    NASA Technical Reports Server (NTRS)

    Santi, L. Michael

    1986-01-01

    Computational predictions of turbulent flow in sharply curved 180 degree turn around ducts are presented. The CNS2D computer code is used to solve the equations of motion for two-dimensional incompressible flows transformed to a nonorthogonal body-fitted coordinate system. This procedure incorporates the pressure velocity correction algorithm SIMPLE-C to iteratively solve a discretized form of the transformed equations. A multiple scale turbulence model based on simplified spectral partitioning is employed to obtain closure. Flow field predictions utilizing the multiple scale model are compared to features predicted by the traditional single scale k-epsilon model. Tuning parameter sensitivities of the multiple scale model applied to turn around duct flows are also determined. In addition, a wall function approach based on a wall law suitable for incompressible turbulent boundary layers under strong adverse pressure gradients is tested. Turn around duct flow characteristics utilizing this modified wall law are presented and compared to results based on a standard wall treatment.

  3. Decline of birds in a human modified coastal dune forest landscape in South Africa.

    PubMed

    Trimble, Morgan J; van Aarde, Rudi J

    2011-01-13

    Previous studies demonstrate that old-growth forest remnants and vegetation regenerating after anthropogenic disturbance provide habitat for birds in a human modified coastal dune forest landscape in northern KwaZulu-Natal, South Africa. However, occurrence does not ensure persistence. Based on a 13-year monitoring database we calculated population trends for 37 bird species and general trends in overall bird density in different vegetation types. We evaluated species' characteristics as covariates of population trend and assessed changes in rainfall and proportional area and survey coverage per vegetation type. 76% of species assessed have declined, 57% significantly so at an average rate of 13.9% per year. Overall, bird density has fallen at 12.2% per year across old-growth forest and woody regenerating vegetation types. Changes in proportional area and coverage per vegetation type may partly explain trends for a few species but are unlikely to account for most. Below average rainfall may have contributed to bird declines. However, other possibilities warrant further investigation. Species with larger range extents tended to decline more sharply than did others, and these species may be responding to environmental changes on a broader geographical scale. Our results cast doubt on the future persistence of birds in this human modified landscape. More research is needed to elucidate the mechanisms driving population decline in the study area and to investigate whether the declines identified here are more widespread across the region and perhaps the continent.

  4. The fertility decline in Kenya.

    PubMed

    Robinson, W C; Harbison, S F

    1995-01-01

    In Sub-Saharan Africa Kenya is a prime example of a country experiencing a rapid decline in fertility and greater contraceptive prevalence. These changes have occurred since 1980 when fertility was high at 8.0 children per woman. In 1993 the total fertility rate (TFR) was 5.4, and the growth rate declined to about 2.0%. This transition is swifter than any country in contemporary Asia or historical Europe. The likely projection for Kenya is attainment of replacement level fertility during the 2020s and a leveling of population at about 100 million persons. Fertility has declined the most in urban areas and central and eastern regions. Bongaarts' proximate determinants (TFR, total marital fertility rate, total natural marital fertility rate, and total fecundity) are reduced to the proportion of currently married women using contraception, the proportion in lactational nonfecund status, and the proportion currently married. Actual fertility change is accounted for by total fertility change of 3.0 children. Lactational infecundability accounts for 0.5 potential births, and changes in marital fertility account for 1.0 reduced births per woman. About 70% of fertility reduction is accounted for by contraception and abortion. During 1977-78 80% of fertility control was due to lactational nonfecundity, 10% to nonmarriage, and 10% to contraception. In 1993 lactational nonfecundity accounted for 50% of the reduction, nonmarriage for 20%, and abortion about 30%. Future fertility is expected to be dependent on contraceptive prevalence. Kenya has experienced the Coale paradigm of preconditions necessary for demographic transition (willing, ready, and able). High fertility in Africa is not intractable. Creating the change in attitudes that leads to readiness is linked to education, health, and exposure to modernizing media and urban lifestyles. The public sector family planning program in Kenya has created the opportunity for access and availability of contraception. The key

  5. Climate change and pollution speed declines in zebrafish populations

    PubMed Central

    Owen, Stewart F.; Peters, James; Zhang, Yong; Soffker, Marta; Paull, Gregory C.; Hosken, David J.; Wahab, M. Abdul; Tyler, Charles R.

    2015-01-01

    Endocrine disrupting chemicals (EDCs) are potent environmental contaminants, and their effects on wildlife populations could be exacerbated by climate change, especially in species with environmental sex determination. Endangered species may be particularly at risk because inbreeding depression and stochastic fluctuations in male and female numbers are often observed in the small populations that typify these taxa. Here, we assessed the interactive effects of water temperature and EDC exposure on sexual development and population viability of inbred and outbred zebrafish (Danio rerio). Water temperatures adopted were 28 °C (current ambient mean spawning temperature) and 33 °C (projected for the year 2100). The EDC selected was clotrimazole (at 2 μg/L and 10 μg/L), a widely used antifungal chemical that inhibits a key steroidogenic enzyme [cytochrome P450(CYP19) aromatase] required for estrogen synthesis in vertebrates. Elevated water temperature and clotrimazole exposure independently induced male-skewed sex ratios, and the effects of clotrimazole were greater at the higher temperature. Male sex ratio skews also occurred for the lower clotrimazole exposure concentration at the higher water temperature in inbred fish but not in outbred fish. Population viability analysis showed that population growth rates declined sharply in response to male skews and declines for inbred populations occurred at lower male skews than for outbred populations. These results indicate that elevated temperature associated with climate change can amplify the effects of EDCs and these effects are likely to be most acute in small, inbred populations exhibiting environmental sex determination and/or differentiation. PMID:25733876

  6. Dietary Factors and Cognitive Decline

    PubMed Central

    Smith, P.J.; Blumenthal, J.A.

    2015-01-01

    Cognitive decline is an increasingly important public health problem, with more than 100 million adults worldwide projected to develop dementia by 2050. Accordingly, there has been an increased interest in preventive strategies that diminish this risk. It has been recognized that lifestyle factors including dietary patterns, may be important in the prevention of cognitive decline and dementia in later life. Several dietary components have been examined, including antioxidants, fatty acids, and B vitamins. In addition, whole dietary eating plans, including the Mediterranean diet (MeDi), and the Dietary Approaches to Stop Hypertension (DASH) diet, with and without weight loss, have become areas of increasing interest. Although prospective epidemiological studies have observed that antioxidants, fatty acids, and B vitamins are associated with better cognitive functioning, randomized clinical trials have generally failed to confirm the value of any specific dietary component in improving neurocognition. Several randomized trials have examined the impact of changing ‘whole’ diets on cognitive outcomes. The MeDi and DASH diets offer promising preliminary results, but data are limited and more research in this area is needed. PMID:26900574

  7. Dietary Factors and Cognitive Decline.

    PubMed

    Smith, P J; Blumenthal, J A

    2016-03-01

    Cognitive decline is an increasingly important public health problem, with more than 100 million adults worldwide projected to develop dementia by 2050. Accordingly, there has been an increased interest in preventive strategies that diminish this risk. It has been recognized that lifestyle factors including dietary patterns, may be important in the prevention of cognitive decline and dementia in later life. Several dietary components have been examined, including antioxidants, fatty acids, and B vitamins. In addition, whole dietary eating plans, including the Mediterranean diet (MeDi), and the Dietary Approaches to Stop Hypertension (DASH) diet, with and without weight loss, have become areas of increasing interest. Although prospective epidemiological studies have observed that antioxidants, fatty acids, and B vitamins are associated with better cognitive functioning, randomized clinical trials have generally failed to confirm the value of any specific dietary component in improving neurocognition. Several randomized trials have examined the impact of changing 'whole' diets on cognitive outcomes. The MeDi and DASH diets offer promising preliminary results, but data are limited and more research in this area is needed.

  8. Intraguild Predation and Native Lady Beetle Decline

    PubMed Central

    Gardiner, Mary M.; O'Neal, Matthew E.; Landis, Douglas A.

    2011-01-01

    Coccinellid communities across North America have experienced significant changes in recent decades, with declines in several native species reported. One potential mechanism for these declines is interference competition via intraguild predation; specifically, increased predation of native coccinellid eggs and larvae following the introduction of exotic coccinellids. Our previous studies have shown that agricultural fields in Michigan support a higher diversity and abundance of exotic coccinellids than similar fields in Iowa, and that the landscape surrounding agricultural fields across the north central U.S. influences the abundance and activity of coccinellid species. The goal of this study was to quantify the amount of egg predation experienced by a native coccinellid within Michigan and Iowa soybean fields and explore the influence of local and large-scale landscape structure. Using the native lady beetle Coleomegilla maculata as a model, we found that sentinel egg masses were subject to intense predation within both Michigan and Iowa soybean fields, with 60.7% of egg masses attacked and 43.0% of available eggs consumed within 48 h. In Michigan, the exotic coccinellids Coccinella septempunctata and Harmonia axyridis were the most abundant predators found in soybean fields whereas in Iowa, native species including C. maculata, Hippodamia parenthesis and the soft-winged flower beetle Collops nigriceps dominated the predator community. Predator abundance was greater in soybean fields within diverse landscapes, yet variation in predator numbers did not influence the intensity of egg predation observed. In contrast, the strongest predictor of native coccinellid egg predation was the composition of edge habitats bordering specific fields. Field sites surrounded by semi-natural habitats including forests, restored prairies, old fields, and pasturelands experienced greater egg predation than fields surrounded by other croplands. This study shows that intraguild

  9. Short-term muscle disuse atrophy is not associated with increased intramuscular lipid deposition or a decline in the maximal activity of key mitochondrial enzymes in young and older males.

    PubMed

    Wall, Benjamin T; Dirks, Marlou L; Snijders, Tim; Stephens, Francis B; Senden, Joan M G; Verscheijden, Marie-Louise; van Loon, Luc J C

    2015-01-01

    Aging is generally accompanied by a progressive loss of skeletal muscle mass and impairments in metabolic function. Even a few days of muscle disuse (such as that occurring during injury or illness) leads to considerable loss of muscle mass and strength. It has been speculated that short, successive periods of muscle disuse throughout the lifespan may be largely responsible for the age-related loss of muscle mass. However, it remains unknown whether such short periods of disuse also induce impairments in metabolic function within skeletal muscle. Here, we investigated the effects of a five day period of muscle disuse on intramyocellular triacylglycerol (IMTG) content, muscle oxidative capacity, and the expression of key genes that regulate oxidative metabolism in healthy young and elderly men. Muscle biopsies were collected from healthy, young (n=12; 23±1y) and elderly (n=12; 70±1y) men prior to and immediately after a five day period of one-legged knee immobilization by way of a full leg cast. At baseline, elderly men had a greater IMTG content when compared with the young (56.2±5.1 and 34.8±7.3μmol·g(-1), respectively; P<0.05) with no changes in either group following immobilization (53.4±5.0 and 35.7±5.0μmol·g(-1), respectively; P>0.05). In line, five days of disuse did not lower citrate synthase, β-HAD or cytochrome C oxidase activity in skeletal muscle tissue. Pyruvate dehydrogenase activity increased following immobilization in the older subjects only, from 0.39±0.06 to 0.55 0.05μmol·g(-1)·min(-1) (71±33%; P<0.01). The skeletal muscle mRNA expression of PGC1α and citrate synthase both declined following immobilization in both the young and elderly subjects. We conclude that five days of muscle disuse does not increase intramuscular lipid deposition or reduce the maximal activity of key mitochondrial enzymes within the skeletal muscle of young or older men.

  10. Adult attachment and declining birthrates.

    PubMed

    Draper, Thomas W; Holman, Thomas B; White, Whitney; Grandy, Shannon

    2007-02-01

    Attachment scores for 658 young adults living in the U.S.A. were obtained using the Experiences in Close Relationships scale. The participants came from a subsample of the RELATE data set, who had also filled out the adult attachment measure. Those young adults living in Utah County, Utah, an area of the country with a higher than normal birthrate (88% members of the Church of Jesus Christ of Latter-day Saints), also had higher than average adult attachment scores. While the methodology was not sufficient to assess causal direction nor eliminate the possibility of unidentified influences, an undiscussed psychological factor, adult attachment, may play a role in the numerical declines observed among nonimmigrant communities in the USA and Europe.

  11. Declining Sunshine for Phoenix Lander

    NASA Technical Reports Server (NTRS)

    2008-01-01

    The yellow line on this graphic indicates the number of hours of sunlight each sol, or Martian day, at the Phoenix landing site's far-northern latitude, beginning with the entire Martian day (about 24 hours and 40 minutes) for the first 90 sols, then declining to no sunlight by about sol 300. The blue tick mark indicates that on Sol 124 (Sept. 29, 2008), the sun is above the horizon for about 20 hours.

    The brown vertical bar represents the period from Nov. 18 to Dec. 24, 2008, around the 'solar conjunction,' when the sun is close to the line between Mars and Earth, affecting communications.

    The green vertical rectangle represents the period from February to November 2009 when the Phoenix lander is expected to be encased in carbon-dioxide ice.

  12. Ways of Dealing with Enrollment Decline

    ERIC Educational Resources Information Center

    Phi Delta Kappan, 1978

    1978-01-01

    Two consultants and superintendents from Livonia (Michigan), New Orleans, Salt Lake City, and Seattle discuss the impact of declining enrollments on the schools and some of the actions school districts are taking to cope with the decline. (IRT)

  13. Arctic sea-ice decline archived by multicentury annual-resolution record from crustose coralline algal proxy.

    PubMed

    Halfar, Jochen; Adey, Walter H; Kronz, Andreas; Hetzinger, Steffen; Edinger, Evan; Fitzhugh, William W

    2013-12-03

    Northern Hemisphere sea ice has been declining sharply over the past decades and 2012 exhibited the lowest Arctic summer sea-ice cover in historic times. Whereas ongoing changes are closely monitored through satellite observations, we have only limited data of past Arctic sea-ice cover derived from short historical records, indirect terrestrial proxies, and low-resolution marine sediment cores. A multicentury time series from extremely long-lived annual increment-forming crustose coralline algal buildups now provides the first high-resolution in situ marine proxy for sea-ice cover. Growth and Mg/Ca ratios of these Arctic-wide occurring calcified algae are sensitive to changes in both temperature and solar radiation. Growth sharply declines with increasing sea-ice blockage of light from the benthic algal habitat. The 646-y multisite record from the Canadian Arctic indicates that during the Little Ice Age, sea ice was extensive but highly variable on subdecadal time scales and coincided with an expansion of ice-dependent Thule/Labrador Inuit sea mammal hunters in the region. The past 150 y instead have been characterized by sea ice exhibiting multidecadal variability with a long-term decline distinctly steeper than at any time since the 14th century.

  14. Arctic sea-ice decline archived by multicentury annual-resolution record from crustose coralline algal proxy

    PubMed Central

    Halfar, Jochen

    2013-01-01

    Northern Hemisphere sea ice has been declining sharply over the past decades and 2012 exhibited the lowest Arctic summer sea-ice cover in historic times. Whereas ongoing changes are closely monitored through satellite observations, we have only limited data of past Arctic sea-ice cover derived from short historical records, indirect terrestrial proxies, and low-resolution marine sediment cores. A multicentury time series from extremely long-lived annual increment-forming crustose coralline algal buildups now provides the first high-resolution in situ marine proxy for sea-ice cover. Growth and Mg/Ca ratios of these Arctic-wide occurring calcified algae are sensitive to changes in both temperature and solar radiation. Growth sharply declines with increasing sea-ice blockage of light from the benthic algal habitat. The 646-y multisite record from the Canadian Arctic indicates that during the Little Ice Age, sea ice was extensive but highly variable on subdecadal time scales and coincided with an expansion of ice-dependent Thule/Labrador Inuit sea mammal hunters in the region. The past 150 y instead have been characterized by sea ice exhibiting multidecadal variability with a long-term decline distinctly steeper than at any time since the 14th century. PMID:24248344

  15. Mortality rates decline in Malaysia.

    PubMed

    1991-11-01

    Experiencing remarkable decreases in mortality rates over the past 3 decades, Malaysia currently has one of the lowest mortality rates among developing countries, a rate that compares favorably with those of developed countries. Between 1957 and 1989, the crude death rate dropped from 12.4/1000 population to 4.6. Over the same period, Malaysia recorded even greater decreases in the infant mortality rate, from 75.5/1000 births to 15.2. The Maternal mortality rate also declined from 1.48 in 1970 to 0.24 in 1988. The data indicates that mortality rates vary from state to state, and that rural areas have a higher mortality than urban areas. According to a study by the National Population and Family Development Board, the use of maternal and child health services has played an important role in reducing neonatal, perinatal, infant, child, and maternal mortality rates. Nearly all women in Malaysia receive antenatal services. While the country has achieved great gains on mortality rates, programs focusing on specific age and socioeconomic groups could lead to even greater reductions. The Minister for National Unity and Social Development, Dato Napsiah Omar, has called for the development of programs designed to improve the population's quality of life.

  16. Measurement of decline of functioning in persons with amyotrophic lateral sclerosis: responsiveness and possible applications of the Functional Independence Measure, Barthel Index, Rehabilitation Activities Profile and Frenchay Activities Index.

    PubMed

    De Groot, Imelda J M; Post, Marcel W M; Van Heuveln, Tineke; Van Den Berg, Leonard H; Lindeman, Eline

    2006-09-01

    It is important not only to monitor the functional change during the course of ALS, but also to determine whether or not the available help is sufficient. This study was performed to determine which generic assessment instrument is most appropriate. A multicentre cohort of patients with ALS was followed for one year. At baseline, six months, and 1 year four instruments were used: Functional Independence Measure (FIM), Rehabilitation Activities Profile (RAP), Barthel Index (BI), and Frenchay Activities Index (FAI). The responsiveness of the measures was examined using effect sizes and standardized response mean statistics. Seventy-three patients at baseline, 63 after six months and 43 after one year were assessed. If calculated on the group that completed all three assessments, the FIM, BI, and RAP showed moderate effect sizes and standardized response means over a period of six months and large effect sizes over 12 months. Based on their responsiveness FIM, BI, and RAP can be used to evaluate limitations in activities and care needs of persons with ALS and to evaluate treatment results in trials. The FIM was the most responsive instrument, although the BI might be easier to use in clinical practice.

  17. Minimal models of growth and decline of microbial populations.

    PubMed

    Juška, Alfonsas

    2011-01-21

    Dynamics of growth and decline of microbial populations were analysed and respective models were developed in this investigation. Analysis of the dynamics was based on general considerations concerning the main properties of microorganisms and their interactions with the environment which was supposed to be affected by the activity of the population. Those considerations were expressed mathematically by differential equations or systems of the equations containing minimal sets of parameters characterizing those properties. It has been found that: (1) the factors leading to the decline of the population have to be considered separately, namely, accumulation of metabolites (toxins) in the medium and the exhaustion of resources; the latter have to be separated again into renewable ('building materials') and non-renewable (sources of energy); (2) decline of the population is caused by the exhaustion of sources of energy but no decline is predicted by the model because of the exhaustion of renewable resources; (3) the model determined by the accumulation of metabolites (toxins) in the medium does not suggest the existence of a separate 'stationary phase'; (4) in the model determined by the exhaustion of energy resources the 'stationary' and 'decline' phases are quite discernible; and (5) there is no symmetry in microbial population dynamics, the decline being slower than the rise. Mathematical models are expected to be useful in getting insight into the process of control of the dynamics of microbial populations. The models are in agreement with the experimental data.

  18. A decomposition analysis of recent fertility decline in Fiji.

    PubMed

    Gubhaju, B; Shahidullah, M

    1990-12-01

    Over the period 1966-86, both the Fijian and Indian populations of Fiji demonstrated declines in fertility. Differentials in the decline were, however, noted with the total fertility rate (TFR) of the Fijian population declining by 26% over the period compared to a 50% decline in the Indian TFR. Moreover, rate declines were not smooth and consistent over the period. Faster fertility decline was experienced in the 1st decade for both groups, slowing in the 2nd decade for Indian women, and stabilizing among the Fijians. This paper decomposes these differential changes in fertility rate into marital structure and marital fertility. The study was conducted using data from the censuses of 1966, 1976, and 1986. For the period 1966-76, declines in marital fertility contributed most to overall TFR decline for both ethnic groups. Marital structure had a reducing effect upon TFR among Indian women in the 1st decaed, but not during the 2nd. Fijian women experienced an overall negative impact from marital structure. Contraception plays an important role in limiting fertility in these 2 populations. Accordingly, differentials in acceptance were noticed, the family planning acceptance rate for Indians being almost twice that of Fijians; 35.6% and 18.7%, respectively in 1986. Compared to Indian women, Fijian women were more literate, more economically active, had higher life expectancies, and experience lower infant mortality rates. Nonetheless, they are not motivated to use family planning. Motivational, cultural, religious, and behavioral factors are suggested as causal factors determining acceptance and use of modern contraceptive methods.

  19. [Concentration or decline in Puebla?].

    PubMed

    Cabrera Becerra, V

    1993-04-01

    Some doubts have been expressed over whether the slowing pace of urbanization suggested by the 1990 census of Mexico was an accurate reflection of changing conditions, or whether it resulted from some intentional or unintended bias. Comparison of data from succeeding censuses indicates that the growth rate of the city of Puebla declined from 6.32% in 1980 to 2.63% in 1990. This work argues that, in Puebla, a trend to deconcentration of the population within the city of Puebla during the 1980s was accompanied by rapid growth in smaller and medium sized nearby cities, resulting in increased overall concentration in Puebla's metropolitan area. The absolute population of the city of Puebla increased from 772,908 in 1980 to 1,007,170 in 1990. The central area of the state of Puebla, which surrounds the city, increased its share of the state population from 51.67% in 1980 to 52.21% in 1990. The number of places with over 5000 inhabitants in the area surrounding the city of Puebla increased from 27 in 1980 to 39 in 1990. Construction of the Puebla-Atlixco highway will undoubtedly attract growth to the area southwest of Puebla. Small cities to the east of Puebla have shown significant growth although their region remains strongly rural. The same process of deconcentration of population in Puebla and concentration in its surrounding metropolitan regions can probably also be detected in patterns of investment of public funds. The trend is likely to continue through the 1990s.

  20. Cognitive Decline and the Default American Lifestyle

    PubMed Central

    2011-01-01

    Objectives. Upward trends in IQ, education, and mental work suggest that cognitive function among seniors should be rising strongly across cohorts. There is little sign of such improvement in recent decades, and some analyses find poorer function in the newer cohorts. This essay explores possible explanations of the anomaly. Methods. Major long-term trends that might increase cognitive impairment are reviewed, and their implications are considered. Results. Physical activity is declining, food is increasingly manufactured, body fat is increasing, diabetes and metabolic syndrome are on the rise, the number of prescription drugs per person is increasing, and the proportion of the population either old or obese is growing. Discussion. Technological and economic development may lower the cognitive function needed for survival. They also lower physical activity in daily life. Sedentary work, transportation, and leisure undermine the aerobic and metabolic fitness required for the brain to perform well. Some prescription drugs impair cognitive function, and others do so when taken for many years or in combination with others. The growing fraction of the population that is either old or obese may further lower physical activity norms and requirements and substitute medical intervention for health, accelerating a trend toward cognitive impairment. PMID:21743052

  1. Rock mass response to the decline in underground coal mining

    SciTech Connect

    Holub, K.

    2006-01-15

    Geomechanical problems of mining in the Ostrava-Karvina Coal Basin were studied on the basis of longterm experience gained from seismological observations. They could serve as reasonable models of rock-mass response to temporary reduction and gradual decline in mining activities and mine closure.

  2. A Longitudinal Examination of Performance Decline in Champion Golfers

    ERIC Educational Resources Information Center

    Baker, J.; Horton, S.; Pearce, W.; Deakin, J. M.

    2005-01-01

    The maintenance of skilled performance is of increasing interest and importance in our aging society. Bortz and Bortz (1996) suggested that cognitive and physical abilities decline at a rate of 0.5% per year from peak performance. However, examinations of expert performance in cognitive-motor activities suggest that performance in these areas can…

  3. Reversing Africa's Decline. Worldwatch Paper 65.

    ERIC Educational Resources Information Center

    Brown, Lester R.; Wolf, Edward C.

    This paper highlights some of the themes that any successful strategy to reverse the decline of Africa must embrace. Africa is a continent experiencing a breakdown in the relationship between people and their natural support systems. Famine and the threat of famine are among the manifestations of this breakdown. This decline can be reversed. To do…

  4. Is University Research on the Decline?

    ERIC Educational Resources Information Center

    Ferne, Georges

    1980-01-01

    Decline in research emphasis in universities is tied to a number of factors: defensive apathy in the university scientific community; weakening links between teaching and research; declining enrollments; problems in interdisciplinary work; employment stability and aging faculty, obsolete equipment, support staff reduction, and growing bureaucracy.…

  5. Aging, Terminal Decline, and Terminal Drop

    ERIC Educational Resources Information Center

    Palmore, Erdman; Cleveland, William

    1976-01-01

    Data from a 20-year longitudinal study of persons over 60 were analyzed by step-wise multiple regression to test for declines in function with age, for terminal decline (linear relationship to time before death), and for terminal drop (curvilinear relationship to time before death). There were no substantial terminal drop effects. (Author)

  6. An Evidence-Based Construction of the Models of Decline of Functioning. Part 1: Two Major Models of Decline of Functioning

    ERIC Educational Resources Information Center

    Okawa, Yayoi; Nakamura, Shigemi; Kudo, Minako; Ueda, Satoshi

    2009-01-01

    The purpose of this study is to confirm the working hypothesis on two major models of functioning decline and two corresponding models of rehabilitation program in an older population through detailed interviews with the persons who have functioning declines and on-the-spot observations of key activities on home visits. A total of 542…

  7. Potential causes for amphibian declines in Puerto Rico

    USGS Publications Warehouse

    Burrowes, P.A.; Joglar, R.L.; Green, David E.

    2004-01-01

    We monitored 11 populations of eight species of Eleutherodactylus in Puerto Rico from 1989 through 2001. We determined relative abundance of active frogs along transects established in the Caribbean National Forest (El Yunque), Carite Forest, San Lorenzo, and in the vicinity of San Juan. Three species (Eleutherodactylus karlschmidti, E. jasperi, and E. eneidae) are presumed to be extinct and eight populations of six different species of endemic Eleutherodactylus are significantly declining at elevations above 400 m. Of the many suspected causes of amphibian declines around the world, we focused on climate change and disease. Temperature and precipitation data from 1970a??2000 were analyzed to determine the general pattern of oscillations and deviations that could be correlated with amphibian declines. We examined a total of 106 tissues taken from museum specimens collected from 1961a??1978 and from live frogs in 2000. We found chytrid fungi in two species collected at El Yunque as early as 1976, this is the first report of chytrid fungus in the Caribbean. Analysis of weather data indicates a significant warming trend and an association between years with extended periods of drought and the decline of amphibians in Puerto Rico. The 1970's and 1990's, which represent the periods of amphibian extirpations and declines, were significantly drier than average. We suggest a possible synergistic interaction between drought and the pathological effect of the chytrid fungus on amphibian populations.

  8. Examining differences between recovered and declining endangered species

    USGS Publications Warehouse

    Abbitt, R.J.F.; Michael, Scott J.

    2001-01-01

    Between 1973 and 1999, 43 species in the United States were reclassified from endangered to threatened or removed entirely from the Endangered Species List. Of these, 23 were identified as recovered. In 1999 the U.S. Fish and Wildlife Service (USFWS) published a list of 33 additional species for possible reclassification and/or delisting. We initiated this study to examine why some endangered species recover but others continue to decline and to identify differences in management activities between these two groups. We defined recovered/recovering species as previously recovered species and the additional recovered/recovering species listed by the USFWS. We defined declining species as those identified as declining in the most recent USFWS Report to Congress. Information on recovered/recovering and declining species was gathered from relevant literature, recovery plans, U.S. Federal Register documents, and individuals responsible for the recovery management of each species. We used this information to examine (1) the percentage of current and historic range covered by management activities; (2) threats affecting the species; (3) population sizes at the time of listing; (4) current versus historic range size; and (5) percentage of recovery management objectives completed. Although few statistical analyses provided significant results, those that did suggest the following differences between recovered/recovering and declining species: (1) recovered/recovering species face threats that are easier to address; (2) recovered/recovering species occupy a greater percentage of their historic range; and (3) recovered/recovering species have a greater percentage of their recovery management objectives completed. Those species with threats easier to address and that occupy a greater percentage of their historic range are recovered/recovering. In contrast, declining species face threats more difficult to address and occupy significantly less of their historic range. If this

  9. Theoretical Analysis of Maximum Flow Declination Rate versus Maximum Area Declination Rate in Phonation

    ERIC Educational Resources Information Center

    Titze, Ingo R.

    2006-01-01

    Purpose: Maximum flow declination rate (MFDR) in the glottis is known to correlate strongly with vocal intensity in voicing. This declination, or negative slope on the glottal airflow waveform, is in part attributable to the maximum area declination rate (MADR) and in part to the overall inertia of the air column of the vocal tract (lungs to…

  10. Asymmetric disassembly and robustness in declining networks

    PubMed Central

    Saavedra, Serguei; Reed-Tsochas, Felix; Uzzi, Brian

    2008-01-01

    Mechanisms that enable declining networks to avert structural collapse and performance degradation are not well understood. This knowledge gap reflects a shortage of data on declining networks and an emphasis on models of network growth. Analyzing >700,000 transactions between firms in the New York garment industry over 19 years, we tracked this network's decline and measured how its topology and global performance evolved. We find that favoring asymmetric (disassortative) links is key to preserving the topology and functionality of the declining network. Based on our findings, we tested a model of network decline that combines an asymmetric disassembly process for contraction with a preferential attachment process for regrowth. Our simulation results indicate that the model can explain robustness under decline even if the total population of nodes contracts by more than an order of magnitude, in line with our observations for the empirical network. These findings suggest that disassembly mechanisms are not simply assembly mechanisms in reverse and that our model is relevant to understanding the process of decline and collapse in a broad range of biological, technological, and financial networks. PMID:18936489

  11. Can exercise prevent cognitive decline?

    PubMed

    Behrman, Sophie; Ebmeier, Klaus P

    2014-01-01

    As the tolerability of pharmacological agents decreases with age, exercise may be particularly helpful as a possible treatment or stabiliser of mood and cognitive function in older age. Exercise has been most commonly evaluated for the treatment of depression. Exercise interventions designed primarily for treatment of physical conditions in the elderly do appear to confer psychological benefits as well, with reduction in depressive symptoms over the course of treatment. The effects of exercise on reducing depressive symptoms are not dissimilar to the effects of antidepressant drugs and cognitive behaviour therapy. Exercise may be a useful low-tech intervention for people with mild to moderate depression. In particular, exercise may be helpful in the elderly and in patients who have had insufficient response to, or are intolerant of, pharmacotherapy. Mastery of a new skill and positive feedback from others may increase feelings of self-esteem and improve mood. Exercise may distract participants from persistent negative thoughts. Exercise has been shown to improve executive function acutely in adults of all ages. It is possible that dance routines or other exercise regimens requiring some cognitive input may confer additional benefit to cognitive function. Exercise has a moderate effect on the ability of people with dementia to perform activities of daily living and may improve cognitive function. Midlife exercise may also have an impact on later cognitive function.

  12. Species decline: Contaminants and other contributing factors

    USGS Publications Warehouse

    Pattee, O.H.; Rattner, B.A.; Eisler, R.

    1998-01-01

    Members of over 1,200 taxa have been listed as Threatened or Endangered, and over 4,000 additional organisms have been identified as Candidate Species or Species of Concern. Identification of critical limiting factors may result in management actions that stabilize vulnerable populations and insure their perpetuation. Both naturally-occurring and anthropogenic activities (e.g., environmental contaminants and pollution) have been demonstrated to be a significant factor in depressing populations or catalyzing the final crash of some species. The objective of this project is to develop a synthesis document and database that lists and ranks the presumed causes of decline, with special emphasis on contaminants and pollutant-related situations. This will be accomplished by synoptic review of all recovery plans (n=479) with listing packages (n=1134) serving as a secondary source of information, followed by itemization, cross-referencing, enumeration, and ranking of contributing and limiting factors. To date we have analyzed all of the recovery plans for reptiles (n=26) and amphibians (n=6). 188 causes are defined, falling into 6 major categories: habitat alteration/availability (47.8%); exploitation/harvest (19.7%); introduction of exotic species (10.1%); contaminants (9.0%); miscellaneous others (6.9%); pollution (6.4%). The applicability of these data are extensive, including facilitating reviews of Section 7 consultations and Environmental Impact Statements, reviewing permit applications, conducting environmental contaminant risk assessments, identifying specific data gaps and research needs, selecting potential management actions, and establishing priorities for broad-based research on limiting factors applicable to groups of species rather than the current species-by-species approach. However. caution must be exercised in the use of this data because of the speculative nature of the causes; most of the causes (69.7%) are based on poorly documented expert opinion and

  13. Decline and conservation of bumble bees.

    PubMed

    Goulson, D; Lye, G C; Darvill, B

    2008-01-01

    Declines in bumble bee species in the past 60 years are well documented in Europe, where they are driven primarily by habitat loss and declines in floral abundance and diversity resulting from agricultural intensification. Impacts of habitat degradation and fragmentation are likely to be compounded by the social nature of bumble bees and their largely monogamous breeding system, which renders their effective population size low. Hence, populations are susceptible to stochastic extinction events and inbreeding. In North America, catastrophic declines of some bumble bee species since the 1990s are probably attributable to the accidental introduction of a nonnative parasite from Europe, a result of global trade in domesticated bumble bee colonies used for pollination of greenhouse crops. Given the importance of bumble bees as pollinators of crops and wildflowers, steps must be taken to prevent further declines. Suggested measures include tight regulation of commercial bumble bee use and targeted use of environmentally comparable schemes to enhance floristic diversity in agricultural landscapes.

  14. Understanding Amphibian Declines Through Geographic Approaches

    USGS Publications Warehouse

    Gallant, Alisa

    2006-01-01

    Growing concern over worldwide amphibian declines warrants serious examination. Amphibians are important to the proper functioning of ecosystems and provide many direct benefits to humans in the form of pest and disease control, pharmaceutical compounds, and even food. Amphibians have permeable skin and rely on both aquatic and terrestrial ecosystems during different seasons and stages of their lives. Their association with these ecosystems renders them likely to serve as sensitive indicators of environmental change. While much research on amphibian declines has centered on mysterious causes, or on causes that directly affect humans (global warming, chemical pollution, ultraviolet-B radiation), most declines are the result of habitat loss and habitat alteration. Improving our ability to characterize, model, and monitor the interactions between environmental variables and amphibian habitats is key to addressing amphibian conservation. In 2000, the U.S. Geological Survey (USGS) initiated the Amphibian Research and Monitoring Initiative (ARMI) to address issues surrounding amphibian declines.

  15. Why did maternal mortality decline in Matlab?

    PubMed

    Maine, D; Akalin, M Z; Chakraborty, J; de Francisco, A; Strong, M

    1996-01-01

    In 1991, an article on the Maternity Care Program in Matlab, Bangladesh, reported a substantial decline in direct obstetric deaths in the intervention area, but not in the control area. The decline was attributed primarily to the posting of midwives at the village level. In this article, data are presented from the same period and area on a variety of intermediate events. They indicate that the decline in deaths was probably due to the combined efforts of community midwives and the physicians at the Matlab maternity clinic. Their ability to refer patients to higher levels of care was important. The data further indicate that the decline in deaths depended upon the functioning of the government hospital in Chandpur, where cesarean sections and blood transfusions were available. Midwives might also have made a special contribution by providing early termination of pregnancy, which is legal in Bangladesh.

  16. Atrial Fibrillation, Cognitive Decline And Dementia

    PubMed Central

    Alonso, Alvaro; Arenas de Larriva, Antonio P.

    2016-01-01

    Atrial fibrillation (AF) is a common cardiac arrhythmia. Growing evidence supports a role for AF as a risk factor for cognitive decline and dementia. In this review, we summarize epidemiologic observations linking AF with cognitive outcomes, describe potential mechanisms, and explore the impact of AF treatments on cognitive decline and dementia. Community-based, observational studies show a consistent higher rate of cognitive decline and risk of dementia in persons with AF. These associations are partly due to the increased risk of clinical stroke in AF, but other mechanisms, including incidence of silent cerebral infarcts, microbleeds, and cerebral hypoperfusion, are likely additional contributors. Adequate oral anticoagulation and improved management of the overall cardiovascular risk profile in persons with AF offer the promise of reducing the impact of AF on cognitive decline and dementia. PMID:27547248

  17. Evaluation of invasions and declines of submersed aquatic macrophytes

    USGS Publications Warehouse

    Chambers, P.A.; Barko, J.W.; Smith, C.S.

    1993-01-01

    During the past 60 yr, sightings of aquatic macrophyte species in geographic regions where they had previously not been found have occurred with increasing frequency, apparently due to both greater dispersal of the plants as a result of human activities as well as better documentation of plant distribution. Intercontinental invasions, such as Myriophyllum spicatum and Hydrilla into North America, Elodea canadensis into Europe and Elodea nuttallii, Egeria densa and Cabomba caroliniana into Japan, have generally been well documented. However, the spread of an exotic species across a continent after its initial introduction (e.g., Potamogeton crispus in North America) or the expansion of a species native to a continent into hitherto unexploited territory (e.g.,the expansion of the North American native Myriophyllum heterophyllum into New England) have received little attention. Natural declines in aquatic macrophyte communities have also received little scientific study although there are many accounts of macrophyte declines. The best-documented example comes from the marine literature where extensive declines of eelgrass (Zostera) occurred in the 1930s along the Atlantic coast due to a pathogenic marine slime mold (''wasting disease''). The aim of this workshop was to identify examples of invasions or natural declines of aquatic macrophyte species throughout the world and assess the importance of environmental factors in their control. Forty-five scientists and aquatic plant managers from ten countries participated in the workshop. Eleven of the participants contributed written evaluations of species invasions and declines in their geo-graphic region. These were distributed to registered participants prior to the meeting and served as the starting-point of workshop discussions. To address the topics raised in the working papers, the participants divided into four working groups to evaluate: 1. Environmental controls of species invasions. 2. Biotic controls of species

  18. Sharply notch cylindrical tension specimen for screening plane-strain fracture toughness. I - Influence of fundamental testing variables on notch strength. II Applications in aluminum alloy quality assurance of fracture toughness

    NASA Technical Reports Server (NTRS)

    Jones, M. H.; Bubsey, R. T.; Brown, W. F., Jr.; Bucci, R. J.; Collis, S. F.; Kohm, R. F.; Kaufman, J. G.

    1977-01-01

    A description is presented of studies which have been conducted to establish an improved technology base for a use of the sharply notched cylindrical specimen in quality assurance tests of aluminum alloy products. The results are presented of an investigation of fundamental variables associated with specimen preparation and testing, taking into account the influence of the notch root radius, the eccentricity of loading, the specimen diameter, and the notch depth on the sharp notch strength. Attention is given to the statistical procedures which are necessary to establish correlations between the sharp notch strength and the plane-strain fracture toughness for high-strength aluminum alloys.

  19. Decline in Cardiorespiratory Fitness and Odds of Incident Sleep Complaints

    PubMed Central

    Dishman, Rodney K.; Sui, Xuemei; Church, Timothy S.; Kline, Christopher E.; Youngstedt, Shawn D.; Blair, Steven N.

    2014-01-01

    Purpose To examine longitudinal change in cardiorespiratory fitness and odds of incident sleep problems. Methods A cohort of 7368 men and 1155 women, aged 20–85 years, from the Aerobics Center Longitudinal Study. The cohort did not complain of sleep problems, depression, or anxiety at their first clinic visit. Cardiorespiratory fitness assessed at 4 clinic visits between 1971–2006, each separated by an average of 2–3 years, was used as a proxy measure of cumulative physical activity exposure. Sleep complaints were made to a physician during follow-up. Results Across visits, there were 784 incident cases of sleep complaints in men and 207 cases in women. After adjustment for age, time between visits, body mass index, smoking, alcohol use, chronic medical conditions, complaints of depression or anxiety at each visit, and fitness at Visit 1, each minute decline in treadmill endurance (i.e., a decline in cardiorespiratory fitness of approximately one-half MET) between ages 51 to 56 increased the odds of incident sleep complaints by 1.7% (1.0–2.4%) in men and 1.3% (0.0–2.8%) in women. Odds were ~8% higher per minute decline in people with sleep complaints at 2 or 3 visits. Conclusion The results indicate that maintenance of cardiorespiratory fitness during middle-age, when decline in fitness typically accelerates and risk of sleep problems is elevated, helps protect against the onset of sleep complaints made to a physician. PMID:25207930

  20. Pesticides and amphibian population declines in California, USA

    USGS Publications Warehouse

    Sparling, Donald W.; Fellers, Gary M.; McConnell, Laura L.

    2001-01-01

    Several species of anuran amphibians have undergone drastic population declines in the western United States over the last 10 to 15 years. In California, the most severe declines are in the Sierra Mountains east of the Central Valley and downwind of the intensely agricultural San Joaquin Valley. In contrast, coastal and more northern populations across from the less agrarian Sacramento Valley are stable or declining less precipitously. In this article, we provide evidence that pesticides are instrumental in declines of these species. Using Hyla regilla as a sentinel species, we found that cholinesterase (ChE) activity in tadpoles was depressed in mountainous areas east of the Central Valley compared with sites along the coast or north of the Valley. Cholinesterase was also lower in areas where ranid population status was poor or moderate compared with areas with good ranid status. Up to 50% of the sampled population in areas with reduced ChE had detectable organophosphorus residues, with concentrations as high as 190 ppb wet weight. In addition, up to 86% of some populations had measurable endosulfan concentrations and 40% had detectable 4,4'- dichlorodiphenyldichloroethylene, 4,4'-DDT, and 2,4'-DDT residues.

  1. Which factors predict cognitive decline in Parkinson's disease?

    PubMed Central

    Caparros-Lefebvre, D; Pécheux, N; Petit, V; Duhamel, A; Petit, H

    1995-01-01

    The study assessed cognitive decline in non-demented, non-depressed patients with well defined Parkinson's disease and determined the predictive value for cognitive decline of different motor symptoms. Motor disability was measured with the Unified Parkinson's disease rating scale, impairment in activities of daily living, levodopa test, and long term clinical follow up. Neuropsychological evaluations included modified mini mental state, fluency, Wechsler logical memory, Wisconsin card sorting test, and the Montgomery and Asberg depression rating scale. Fifty three patients fulfilling clinical criteria for idiopathic Parkinson's disease were studied. Cognitive performance on initial testing was significantly correlated with education and disease duration but not with age at disease onset. Cognitive performance on retesting after three years of follow up was significantly reduced. This reduction was significantly greater in the late onset group, in patients with isolated dystonic dyskinesiae, and in patients with a lower percentage of motor improvement on levodopa. Cognitive decline in idiopathic Parkinson's disease may depend on both the prevalence of non-dopaminergic lesions and the topography of dopaminergic denervation. Predictive factors for cognitive decline, especially in executive tasks, relate more to non-dopaminergic than to dopaminergic lesions. PMID:7823067

  2. Ethanol and Isopropanol in Concentrations Present in Hand Sanitizers Sharply Reduce Excystation of Giardia and Entamoeba and Eliminate Oral Infectivity of Giardia Cysts in Gerbils

    PubMed Central

    Chatterjee, Aparajita; Bandini, Giulia; Motari, Edwin

    2015-01-01

    Enteric protozoan parasites, which are spread by the fecal-oral route, are important causes of diarrhea (Giardia duodenalis) and amebic dysentery (Entamoeba histolytica). Cyst walls of Giardia and Entamoeba have a single layer composed of fibrils of β-1,3-linked GalNAc and β-1,4-linked GlcNAc (chitin), respectively. The goal here was to determine whether hand sanitizers that contain ethanol or isopropanol as the active microbicide might reduce transmission of these parasites. We found that treatment with these alcohols with or without drying in a rotary evaporator (to model rapid evaporation of sanitizers on hands) kills 85 to 100% of cysts of G. duodenalis and 90 to 100% of cysts of Entamoeba invadens (a nonpathogenic model for E. histolytica), as shown by nuclear labeling with propidium iodide and failure to excyst in vitro. Alcohols with or without drying collapsed the cyst walls of Giardia but did not collapse the cyst walls of Entamoeba. To validate the in vitro results, we showed that treatment with alcohols eliminated oral infection of gerbils by 1,000 G. duodenalis cysts, while a commercial hand sanitizer (Purell) killed E. invadens cysts that were directly applied to the hands. These results suggest that expanded use of alcohol-based hand sanitizers might reduce the transmission of Giardia and Entamoeba. PMID:26282413

  3. Ethanol and isopropanol in concentrations present in hand sanitizers sharply reduce excystation of Giardia and Entamoeba and eliminate oral infectivity of Giardia cysts in gerbils.

    PubMed

    Chatterjee, Aparajita; Bandini, Giulia; Motari, Edwin; Samuelson, John

    2015-11-01

    Enteric protozoan parasites, which are spread by the fecal-oral route, are important causes of diarrhea (Giardia duodenalis) and amebic dysentery (Entamoeba histolytica). Cyst walls of Giardia and Entamoeba have a single layer composed of fibrils of β-1,3-linked GalNAc and β-1,4-linked GlcNAc (chitin), respectively. The goal here was to determine whether hand sanitizers that contain ethanol or isopropanol as the active microbicide might reduce transmission of these parasites. We found that treatment with these alcohols with or without drying in a rotary evaporator (to model rapid evaporation of sanitizers on hands) kills 85 to 100% of cysts of G. duodenalis and 90 to 100% of cysts of Entamoeba invadens (a nonpathogenic model for E. histolytica), as shown by nuclear labeling with propidium iodide and failure to excyst in vitro. Alcohols with or without drying collapsed the cyst walls of Giardia but did not collapse the cyst walls of Entamoeba. To validate the in vitro results, we showed that treatment with alcohols eliminated oral infection of gerbils by 1,000 G. duodenalis cysts, while a commercial hand sanitizer (Purell) killed E. invadens cysts that were directly applied to the hands. These results suggest that expanded use of alcohol-based hand sanitizers might reduce the transmission of Giardia and Entamoeba.

  4. Trematode infection causes malformations and population effects in a declining New Zealand fish.

    PubMed

    Kelly, David W; Thomas, Harriet; Thieltges, David W; Poulin, Robert; Tompkins, Daniel M

    2010-03-01

    1. Animal malformations engender wide public and scientific concern because of associated environmental health risks. This is highlighted by increased incidence of limb malformations in amphibians associated with trematode infections and disturbance. Malformations may signal new emerging disease threats, but whether the phenomenon is broadly applicable across taxa, or has population-scale impacts, is unknown. 2. Malformations are widely reported in fish and, until now, have been attributed mainly to contaminants. We tested whether the trematode Telogaster opisthorchis caused severe malformations, leading to population effects, in Galaxias anomalus, a threatened New Zealand freshwater fish. 3. Experimental infection of larval fish caused increasing spinal malformation and mortality with infection intensity that closely matched field patterns. Field malformation frequency peaked in January (65%), before declining sharply in February (25%) and remaining low thereafter. 4. The peak occurred during a 'critical window' of larval development, with the decline coincident with a population crash, indicating that malformation was causing mortality in the field. 5. The occurrence of such critical developmental windows may explain why this mechanism of population impact has been overlooked. With global environmental stressors predicted to enhance trematode infections, our results show that parasite-induced malformation, and its population-scale impacts, could be more widespread than previously considered.

  5. Predicting how populations decline to extinction

    PubMed Central

    Collen, Ben; McRae, Louise; Deinet, Stefanie; De Palma, Adriana; Carranza, Tharsila; Cooper, Natalie; Loh, Jonathan; Baillie, Jonathan E. M.

    2011-01-01

    Global species extinction typically represents the endpoint in a long sequence of population declines and local extinctions. In comparative studies of extinction risk of contemporary mammalian species, there appear to be some universal traits that may predispose taxa to an elevated risk of extinction. In local population-level studies, there are limited insights into the process of population decline and extinction. Moreover, there is still little appreciation of how local processes scale up to global patterns. Advancing the understanding of factors which predispose populations to rapid declines will benefit proactive conservation and may allow us to target at-risk populations as well as at-risk species. Here, we take mammalian population trend data from the largest repository of population abundance trends, and combine it with the PanTHERIA database on mammal traits to answer the question: what factors can be used to predict decline in mammalian abundance? We find in general that environmental variables are better determinants of cross-species population-level decline than intrinsic biological traits. For effective conservation, we must not only describe which species are at risk and why, but also prescribe ways to counteract this. PMID:21807738

  6. Periodontitis and Cognitive Decline in Alzheimer's Disease.

    PubMed

    Ide, Mark; Harris, Marina; Stevens, Annette; Sussams, Rebecca; Hopkins, Viv; Culliford, David; Fuller, James; Ibbett, Paul; Raybould, Rachel; Thomas, Rhodri; Puenter, Ursula; Teeling, Jessica; Perry, V Hugh; Holmes, Clive

    2016-01-01

    Periodontitis is common in the elderly and may become more common in Alzheimer's disease because of a reduced ability to take care of oral hygiene as the disease progresses. Elevated antibodies to periodontal bacteria are associated with an increased systemic pro-inflammatory state. Elsewhere raised serum pro-inflammatory cytokines have been associated with an increased rate of cognitive decline in Alzheimer's disease. We hypothesized that periodontitis would be associated with increased dementia severity and a more rapid cognitive decline in Alzheimer's disease. We aimed to determine if periodontitis in Alzheimer's disease is associated with both increased dementia severity and cognitive decline, and an increased systemic pro inflammatory state. In a six month observational cohort study 60 community dwelling participants with mild to moderate Alzheimer's Disease were cognitively assessed and a blood sample taken for systemic inflammatory markers. Dental health was assessed by a dental hygienist, blind to cognitive outcomes. All assessments were repeated at six months. The presence of periodontitis at baseline was not related to baseline cognitive state but was associated with a six fold increase in the rate of cognitive decline as assessed by the ADAS-cog over a six month follow up period. Periodontitis at baseline was associated with a relative increase in the pro-inflammatory state over the six month follow up period. Our data showed that periodontitis is associated with an increase in cognitive decline in Alzheimer's Disease, independent to baseline cognitive state, which may be mediated through effects on systemic inflammation.

  7. Global phytoplankton decline over the past century.

    PubMed

    Boyce, Daniel G; Lewis, Marlon R; Worm, Boris

    2010-07-29

    In the oceans, ubiquitous microscopic phototrophs (phytoplankton) account for approximately half the production of organic matter on Earth. Analyses of satellite-derived phytoplankton concentration (available since 1979) have suggested decadal-scale fluctuations linked to climate forcing, but the length of this record is insufficient to resolve longer-term trends. Here we combine available ocean transparency measurements and in situ chlorophyll observations to estimate the time dependence of phytoplankton biomass at local, regional and global scales since 1899. We observe declines in eight out of ten ocean regions, and estimate a global rate of decline of approximately 1% of the global median per year. Our analyses further reveal interannual to decadal phytoplankton fluctuations superimposed on long-term trends. These fluctuations are strongly correlated with basin-scale climate indices, whereas long-term declining trends are related to increasing sea surface temperatures. We conclude that global phytoplankton concentration has declined over the past century; this decline will need to be considered in future studies of marine ecosystems, geochemical cycling, ocean circulation and fisheries.

  8. Update: Exertional hyponatremia, active component, U.S. Armed Forces, 1999-2013.

    PubMed

    2014-03-01

    From 1999 through 2013, there were 1,406 incident diagnoses of exertional hyponatremia among active component members of the U.S. Armed Forces. Annual incidence rates rose sharply from 2008 to 2010 but decreased by 59 percent from 2010 to 2013. In 2013, there were fewer incident cases (n=73) than in any of the previous 9 years. The recent decrease in overall rates reflects sharply declining rates in the Marine Corps and slight decreases in the other Services. Relative to their respective counterparts, crude incidence rates of exertional hyponatremia for the entire 15-year surveillance period were higher among females, those in the youngest age group, Marines, recruit trainees, and "other" military occupations. Service members (particularly recruit trainees) and their supervisors must be vigilant for early signs of heat-related illnesses and must be knowledgeable of the dangers of excessive water consumption and the prescribed limits for water intake during prolonged physical activity (e.g., field training exercises, personal fitness training, recreational activities) in hot, humid weather.

  9. Biomarkers of cognitive decline in Parkinson's disease.

    PubMed

    Lin, Chin-Hsien; Wu, Ruey-Meei

    2015-05-01

    Cognitive impairment is a frequent and devastating non-motor symptom of Parkinson's disease (PD). Impaired cognition has a major impact on either quality of life or mortality in patients with PD. Notably, the rate of cognitive decline and pattern of early cognitive deficits in PD are highly variable between individuals. Given that the underlying mechanisms of cognitive decline or dementia associated with PD remain unclear, there is currently no mechanism-based treatment available. Identification of biological markers, including neuroimaging, biofluids and common genetic variants, that account for the heterogeneity of PD related cognitive decline could provide important insights into the pathological processes that underlie cognitive impairment in PD. These combined biomarker approaches will enable early diagnosis and provide indicators of cognitive progression in PD patients. This review summarizes recent advances in the development of biomarkers for cognitive impairments in PD.

  10. THE HEALTH EFFECTS OF ECONOMIC DECLINE

    PubMed Central

    Catalano, Ralph; Goldman-Mellor, Sidra; Saxton, Katherine; Margerison-Zilko, Claire; Subbaraman, Meenakshi; LeWinn, Kaja; Anderson, Elizabeth

    2013-01-01

    The recent recession and lingering high unemployment will likely lead to a burst of research studying the health effects of economic decline. We aim to inform that work by summarizing empirical research concerned with those effects. We separate the studies into groups defined by questions asked, mechanisms invoked, and outcomes studied. We conclude that although much research shows that undesirable job and financial experiences increase the risk of psychological and behavioral disorder, many other suspected associations remain poorly studied or unsupported. The intuition that mortality increases when the economy declines, for example, appears wrong. We note that the research informs public health programming by identifying risk factors, such as job loss, made more frequent by economic decline. The promise that the research would identify health costs and benefits of economic policy choices, however, remains unfulfilled and will likely remain so without stronger theory and greater methodological agreement. PMID:21054175

  11. Flowering plants under global pollinator decline.

    PubMed

    Thomann, Michel; Imbert, Eric; Devaux, Céline; Cheptou, Pierre-Olivier

    2013-07-01

    There is now compelling evidence of a reduction of pollinator richness and density at a global scale. In this opinion article, we argue that such pollinator decline intensifies pollen limitation and reduces plant reproductive success, threatening natural populations of extinction. We use genetic architecture and selection experiments on floral traits and evaluate the potential for plant reproductive strategies to adapt rapidly to new pollination environments. We propose that plant reproductive strategies could adapt to the current pollinator decline by decreasing or increasing their reliance to pollinators, for example, increasing autonomous selfing or reinforcing interactions with pollinators. We further discuss if and how adaptation of plant reproductive strategies can buffer the demographic consequences of pollinator decline, and possibly rescue plant populations from extinction.

  12. Nutrition, the brain and cognitive decline: insights from epigenetics.

    PubMed

    Dauncey, M J

    2014-11-01

    Nutrition affects the brain throughout life, with profound implications for cognitive decline and dementia. These effects are mediated by changes in expression of multiple genes, and responses to nutrition are in turn affected by individual genetic variability. An important layer of regulation is provided by the epigenome: nutrition is one of the many epigenetic regulators that modify gene expression without changes in DNA sequence. Epigenetic mechanisms are central to brain development, structure and function, and include DNA methylation, histone modifications and non-protein-coding RNAs. They enable cell-specific and age-related gene expression. Although epigenetic events can be highly stable, they can also be reversible, highlighting a critical role for nutrition in prevention and treatment of disease. Moreover, they suggest key mechanisms by which nutrition is involved in the pathogenesis of age-related cognitive decline: many nutrients, foods and diets have both immediate and long-term effects on the epigenome, including energy status, that is, energy intake, physical activity, energy metabolism and related changes in body composition, and micronutrients involved in DNA methylation, for example, folate, vitamins B6 and B12, choline, methionine. Optimal brain function results from highly complex interactions between numerous genetic and environmental factors, including food intake, physical activity, age and stress. Future studies linking nutrition with advances in neuroscience, genomics and epigenomics should provide novel approaches to the prevention of cognitive decline, and treatment of dementia and Alzheimer's disease.

  13. The Dynamics of Neighborhood Change and Decline.

    ERIC Educational Resources Information Center

    Grigsby, William; And Others

    The economic and physical decline of urban neighborhoods has become a widespread and widely misunderstood phenomenon in post-war America. It has not been restricted to aging central cities: most growing cities and many suburbs possess areas of decay as well. After decades of changing occupancy, dwellings have fallen into disrepair, and the quality…

  14. The Decline of Direct Newspaper Competition.

    ERIC Educational Resources Information Center

    Rosse, James N.

    1980-01-01

    Describes the decline of direct newspaper competition in terms of the loss of effective newspaper market segmentation. Examines the following influences on market segmentation: shift in advertising demand, advertiser preferences for differentiated audiences, shift in subscriber demand, growth of alternative media, increasing production costs, and…

  15. Growth and Decline Processes in Organizations

    ERIC Educational Resources Information Center

    Freeman, John; Hannan, Michael T.

    1975-01-01

    Formulates and tests a model that distinguishes effects of growth and decline among organizational components. Analysis of changes in sizes of personnel categories in 805 California school districts supports the model. (Available from Executive Office, American Sociological Association, 1722 N Street, N.W., Washington, D.C. 20036, $15.00 per year…

  16. Must Declining Enrollment Mean Closing Schools?

    ERIC Educational Resources Information Center

    Fredrickson, John H.

    Effective long-range planning by school districts is an imperative in dealing with declining enrollments. School districts should (1) evaluate present programs in light of current statutory regulations and educational trends and innovations; (2) appraise the structural qualities of existing school facilities; (3) conduct communitywide surveys to…

  17. Predicting Succession under Conditions of Enrollment Decline.

    ERIC Educational Resources Information Center

    Berger, Michael A.

    Three possible explanations for superintendent succession focus on poor administrative performance, district response strategies, and the politics of the chief executive's relationship with the school board. To analyze succession in the context of declining enrollment, a case study survey was conducted of 56 school districts whose peak enrollment…

  18. Disease management strategy for macadamia quick decline

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Trees infected with Macadamia Quick Decline (MQD) exhibit excessive sap bleeding from the trunk, frass from ambrosia beetle feeding, orange fruiting bodies of the fungus Nectria rugulosa and yellowing and browning of the leaves within the tree canopy. MQD threatens commercial and residential product...

  19. Managing Decline and Staffing Standards for Quality.

    ERIC Educational Resources Information Center

    Costanzo, Matthew W.

    School boards, administrators, and representatives of the community should develop long-range plans that not only consider the present state of schools but attempt to project 10 years hence. Demographic changes in communities indicate that managing decline will require a willingness to pare expenditures and an attempt to win back citizens'…

  20. Cholesterol and late-life cognitive decline.

    PubMed

    van Vliet, Peter

    2012-01-01

    High cholesterol levels are a major risk factor for cardiovascular disease, but their role in dementia and cognitive decline is less clear. This review highlights current knowledge on the role of cholesterol in late-life cognitive function, cognitive decline, and dementia. When measured in midlife, high cholesterol levels associate with an increased risk of late-life dementia and cognitive decline. However, when measured in late-life, high cholesterol levels show no association with cognitive function, or even show an inverse relation. Although statin treatment has been shown to associate with a lower risk of dementia and cognitive decline in observational studies, randomized controlled trials show no beneficial effect of statin treatment on late-life cognitive function. Lowering cholesterol levels may impair brain function, since cholesterol is essential for synapse formation and maturation and plays an important role in the regulation of signal transduction through its function as a component of the cell membrane. However, membrane cholesterol also plays a role in the formation and aggregation of amyloid-β. Factors that influence cholesterol metabolism, such as dietary intake, are shown to play a role in late-life cognitive function and the risk of dementia. In conclusion, cholesterol associates with late-life cognitive function, but the association is strongly age-dependent. There is no evidence that treatment with statins in late-life has a beneficial effect on cognitive function.

  1. Careerism and the Decline of Regional Geography.

    ERIC Educational Resources Information Center

    Fairweather, Malcolm; Rumney, Thomas

    The aim of this paper is to offer possible explanations for the declining interest in regional geography. One of the major contributing factors is employment potential. Employment is perceived as being relatively limited for persons defining their interests as "regional" within geography. Students, therefore, do not enroll in regional geography…

  2. The "Decline" of Private Higher Education

    ERIC Educational Resources Information Center

    Levy, Daniel C.

    2013-01-01

    No topic in private higher education study has attracted as great attention globally as has growth. This is appropriate as private growth has soared to nearly a third of the world's total higher education enrolment. But while private growth continues to be the dominant trend, important declines in private shares have emerged. These must be…

  3. Complexity versus certainty in understanding species’ declines

    USGS Publications Warehouse

    Sundstrom, Shana M.; Allen, Craig R.

    2014-01-01

    Traditional approaches to predict species declines (e.g. government processes or IUCN Red Lists), may be too simplistic and may therefore misguide management and conservation. Using complex systems approaches that account for scale-specific patterns and processes have the potential to overcome these limitations.

  4. Black Rural Land Decline in the South

    ERIC Educational Resources Information Center

    McGee, Leo; Boone, Robert

    1977-01-01

    Notes that it is widely accepted that millions of blacks who migrated from the South contributed significantly to the decline of black rural land ownership. However, the less than altruistic behavior patterns of land officials has also contributed to the loss of rural land by blacks. (Author/AM)

  5. Prevalence of Hunger Declines in Rural Households.

    ERIC Educational Resources Information Center

    Nord, Mark; Winicki, F. Joshua

    2000-01-01

    The prevalence of hunger in rural households declined slightly from 1995 to 1998, and food insecurity rates stayed constant. Food insecurity was almost three times as prevalent among rural Blacks as among rural Whites. For rural Hispanics, the rate was about twice that of Whites. Food insecurity was higher in single-parent families than in any…

  6. Exploring the Global Decline of Music Education

    ERIC Educational Resources Information Center

    Aróstegui, José Luis

    2016-01-01

    This article seeks to explain the disjuncture between the decline of music education in schools and the importance music has in popular youth culture and in creativity within the new knowledge economy. The data discussed in this article have been derived from analyses of major documents on curriculum reform as well as e-mail responses from music…

  7. Management of Programs with Declining Enrollments.

    ERIC Educational Resources Information Center

    1980

    The time to begin caring about declining enrollments in community college programs is before the program is started. Program planning should take into account why industry is demanding a given program "right now," avoid developing crash programs, and obtain and utilize all of the information possible including survey data, Labor Department…

  8. Declining Enrollments: Staffing for the Eighties.

    ERIC Educational Resources Information Center

    Fowler, Delbert H.

    School districts that survive declining enrollments will be the ones who recognize that the problem exists and build their programs and plans to meet the problem. It is necessary to know community demography and develop farsighted, actuarily sound projections of the effects. As money is basic to the problem, it is necessary to know the fiscal…

  9. The Decline of Literature: A Public Perspective

    ERIC Educational Resources Information Center

    Albalawi, Mohammed

    2015-01-01

    After centuries of dominance, literature has not been in a robust health for the last few decades. Several scholars have addressed the decline of literature in a number of books and articles attributing it to institutional and economic reasons. However, a major factor has not been taken into account. It is the larger audience who receives and…

  10. Microglia mediate postoperative hippocampal inflammation and cognitive decline in mice

    PubMed Central

    Feng, Xiaomei; Valdearcos, Martin; Uchida, Yosuke; Lutrin, David; Maze, Mervyn; Koliwad, Suneil K.

    2017-01-01

    Surgery can induce cognitive decline, a risk that increases with advancing age. In rodents, postoperative cognitive decline (POCD) is associated with the inflammatory activation of hippocampal microglia. To examine the role of microglia in POCD, we inhibited the colony-stimulating factor 1 receptor (CSF1R) in adult mice, effectively depleting CNS microglia. Surgical trauma (tibial fracture) reduced the ability of mice to remember a conditioned response learned preoperatively, a deficit more pronounced and persistent in mice with diet-induced obesity (DIO). Whereas microglial depletion by itself did not affect learning or memory, perioperative microglial depletion remarkably protected mice, including those with DIO, from POCD. This protection was associated with reduced hippocampal levels of inflammatory mediators, abrogation of hippocampal recruitment of CCR2+ leukocytes, and higher levels of circulating inflammation-resolving factors. Targeting microglia may thus be a viable strategy to mitigate the development of POCD, particularly in those with increased vulnerability.

  11. Hiring of Science Graduates Up Sharply

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1977

    1977-01-01

    A survey conducted by the College Placement Council indicates that employment for chemical professionals has made solid gains in the Spring of 1977, especially in the hiring of new graduates by industry, schools, and government. The largest hiring increases occurred in the aerospace, electronics, petroleum, and glass/paper packaging categories.…

  12. UN projections assume fertility decline, mortality increase.

    PubMed

    Haub, C

    1998-12-01

    This article summarizes the latest findings from the UN Population Division's 1998 review of World Population Estimates and Projections. The revisions reflect lower future population size and faster rates of fertility and mortality decline. The medium variant of population projection for 2050 indicates 8.9 billion, which is 458 million lower than projected in 1996 and 924 million lower than projected in 1994. The changes are due to changes in developing countries. Africa's changes accounted for over 50% of the change. The UN medium projection assumes that the desire for fewer children and effective contraceptive practice will continue and that the availability of family planning services will increase. The revisions are also attributed to the widespread prevalence of AIDS in sub-Saharan Africa and greater chances for lower fertility in developing countries. AIDS mortality may decrease average life expectancy in 29 African countries by 7 years. The UN medium projection assumes a decline in fertility from 2.7 children/woman during 1995-2000 to 2.0 children/woman by 2050. The UN high variant is 10.7 billion by 2050; the low variant is 7.3 billion. It is concluded that efforts of national governments and international agencies have contributed to increased access to reproductive health services and subsequent fertility decline. Future declines will depend on accessibility issues. Despite declines, world population is still growing by 78 million annually. Even countries such as Botswana, with 25% of the population infected with HIV/AIDS, will double in size by 2050.

  13. Climate change, multiple stressors, and the decline of ectotherms.

    PubMed

    Rohr, Jason R; Palmer, Brent D

    2013-08-01

    Climate change is believed to be causing declines of ectothermic vertebrates, but there is little evidence that climatic conditions associated with declines have exceeded critical (i.e., acutely lethal) maxima or minima, and most relevant studies are correlative, anecdotal, or short-term (hours). We conducted an 11-week factorial experiment to examine the effects of temperature (22 °C or 27 °C), moisture (wet or dry), and atrazine (an herbicide; 0, 4, 40, 400 μg/L exposure as embryos and larvae) on the survival, growth, behavior, and foraging rates of postmetamorphic streamside salamanders (Ambystoma barbouri), a species of conservation concern. The tested climatic conditions were between the critical maxima and minima of streamside salamanders; thus, this experiment quantified the long-term effects of climate change within the noncritical range of this species. Despite a suite of behavioral adaptations to warm and dry conditions (e.g., burrowing, refuge use, huddling with conspecifics, and a reduction in activity), streamside salamanders exhibited significant loss of mass and significant mortality in all but the cool and moist conditions, which were closest to the climatic conditions in which they are most active in nature. A temperature of 27 °C represented a greater mortality risk than dry conditions; death occurred rapidly at this temperature and more gradually under cool and dry conditions. Foraging decreased under dry conditions, which suggests there were opportunity costs to water conservation. Exposure to the herbicide atrazine additively decreased water-conserving behaviors, foraging efficiency, mass, and time to death. Hence, the hypothesis that moderate climate change can cause population declines is even more plausible under scenarios with multiple stressors. These results suggest that climate change within the noncritical range of species and pollution may reduce individual performance by altering metabolic demands, hydration, and foraging effort

  14. Decline in Cardiorespiratory Fitness and Odds of Incident Depression

    PubMed Central

    Dishman, Rodney K.; Sui, Xuemei; Church, Timothy S.; Hand, Gregory A.; Trivedi, Madhukar H.; Blair, Steven N.

    2012-01-01

    Background Studies of physical activity and incidence of physician-diagnosed depression have been limited to a single estimate of self-reported physical activity exposure, despite follow-up periods lasting many years. Purpose To examine longitudinal change in cardiorespiratory fitness, an objective marker of habitual physical activity, and incident depression complaints made to a physician. Methods Cardiorespiratory fitness assessed at four clinic visits between 1971 and 2006, each separated by an average of 2–3 years, was used to objectively measure cumulative physical activity exposure in cohorts of 7936 men and 1261 women, aged 20–85 years, from the Aerobics Center Longitudinal Study who did not complain of depression at their first clinic visit in 1971–2003. Data were analyzed in August 2010. Results Across subsequent visits, there were 446 incident cases in men and 153 cases in women. After adjustment for age, time between visits, BMI at each visit, and fitness at Visit 1, each 1-minute decline in treadmill endurance (i.e., a decline in cardiorespiratory fitness of approximately 1 half-MET) between ages 51 and 55 years in men and ages 53 and 56 years in women, increased the odds of incident depression complaints by approximately 2% and 9.5%, respectively. The increased odds remained significant but were attenuated to 1.3% and 5.4% after further adjustment at each visit for smoking, alcohol use, chronic medical conditions, anxiety, and sleep problems. Conclusions Maintenance of cardiorespiratory fitness during late middle-age, when decline in fitness typically accelerates, helps protect against the onset of depression complaints made to a physician. PMID:22992353

  15. Analysis of production decline in geothermal reservoirs

    SciTech Connect

    Zais, Elliot J.; Bodvarsson, Gunnar

    1980-09-01

    The major objectives of the Decline Curve project were to: (1) test the decline analysis methods used in the petroleum industry on geothermal production data; (2) examine and/or develop new analysis methods; and (3) develop a standard operating procedure for analyzing geothermal production data. Various analysis methods have long been available but they have not been tested on geothermal data because of the lack of publicly available data. The recent release to publication of substantial data sets from Wairakei, New Zealand, Cerro Prieto, Mexico and The Geysers, USA has made this study possible. Geothermal reservoirs are quite different from petroleum reservoirs in many ways so the analysis methods must be tested using geothermal data.

  16. The decline of North American freshwater fishes

    USGS Publications Warehouse

    Walsh, Stephen J.; Jelks, Howard L.; Burkhead, Noel M.

    2009-01-01

    North America has a broad array of freshwater ecosystems because of the continent's complex geography and geological history. Within a multitude of habitats—that include streams, large rivers, natural lakes, springs, and wetlands—rich assemblages of fishes reside, representing diverse taxonomic groups with unique ecological requirements. They face an unprecedented conservation crisis.1 In the last few decades, the proportion of inland fishes of North America, which are considered imperiled or extinct, increased from 20 to 40%.2 Although extinctions have occurred, many species and populations are declining in range size and abundance. The fish biota of the continent as a whole remains diverse; however, we can take action to stem any further declines.

  17. Is Canada's sex ratio in decline?

    PubMed Central

    Dodds, L; Armson, B A

    1997-01-01

    In this issue (see pages 37 to 41) Dr. Bruce B. Allan and associates report a small but statistically significant decrease--of about 0.2%--in the proportion of male live births in Canada over the period 1970-90. In this editorial, factors that have been reported in the literature to influence sex ratio are examined within a Canadian context. The authors suggest that although the reasons for the apparent decline in the sex ratio in Canada are unclear, the increasing use of ovulation induction may be a contributing factor. Data from the Nova Scotia Atlee Perinatal Database are discussed with a view to explaining the trend observed in Atlantic Canada, but no obvious explanation emerges. The authors argue that when the period of observation is extended no overall change in the sex ratio is apparent. This would suggest a tendency toward stabilization rather than decline. PMID:9006564

  18. Decline of the lunar core dynamo

    NASA Astrophysics Data System (ADS)

    Tikoo, Sonia M.; Weiss, Benjamin P.; Cassata, William S.; Shuster, David L.; Gattacceca, Jérôme; Lima, Eduardo A.; Suavet, Clément; Nimmo, Francis; Fuller, Michael D.

    2014-10-01

    Recent analyses of Apollo samples have demonstrated that a core dynamo existed on the Moon between at least 4.25 and 3.56 billion years ago (Ga) with surface field intensities reaching ˜70 μT. However, it is unknown when the Moon's magnetic field declined. Determining the temporal evolution of the dynamo is important because it constrains secular changes in power at the lunar core-mantle boundary and, by implication, the Moon's thermal and orbital evolution and the field generation mechanism. Here we present paleomagnetic data from several younger mare basalts which demonstrate that the surface magnetic field had declined precipitously to <˜4 μT by 3.19 Ga. It is currently unclear whether such a rapid decrease in field strength reflects either the cessation of the dynamo during this period or its persistence beyond 3.19 Ga in a drastically weakened state.

  19. Social differences in the decline of marital reproduction in rural Navarre (Spain).

    PubMed

    Sanchez, J J

    1998-09-01

    The continued decline of marital fertility in Navarre, Spain, during the first few decades of the 20th century was associated with an increase in life expectancy and greater survival to adulthood. While the decline affected all social strata and geographical regions, it was not homogeneous, with some sectors of Navarrese society beginning the fertility transition earlier than others. Using data drawn from the nominal lists of the 1940 Spanish Census on married women aged 45-49 years, the author investigated the influence of differences in geographical origin, level of urbanization, father's occupation, level of religious devotion, and political factors upon the observed decline in marital fertility. The data support the originators of demographic transition theory, that the more urban populations, and therefore those with a higher percentage of the active population working in nonprimary sectors, led the fertility decline. The degree of a society's secularization also influenced the beginning of the decline of fertility and the levels reached.

  20. Emerging infectious diseases and amphibian population declines.

    PubMed Central

    Daszak, P.; Berger, L.; Cunningham, A. A.; Hyatt, A. D.; Green, D. E.; Speare, R.

    1999-01-01

    We review recent research on the pathology, ecology, and biogeography of two emerging infectious wildlife diseases, chytridiomycosis and ranaviral disease, in the context of host-parasite population biology. We examine the role of these diseases in the global decline of amphibian populations and propose hypotheses for the origins and impact of these panzootics. Finally, we discuss emerging infectious diseases as a global threat to wildlife populations. PMID:10603206

  1. What we know and don't know about amphibian declines in the West

    USGS Publications Warehouse

    Corn, Paul Stephen

    1994-01-01

    The problem of declining amphibian species is thought to be particularly acute in western North America, but there are many gaps in our knowledge. Although several declines have been well-documented, other declines are anecdotal or hypothesized. Most documented declines are of ranid frogs or toads (Bufo). Species from montane habitats and those occurring in California have been best studied. Status of many desert species is unknown. Habitat destruction and introduced predators are the most common threats to amphibian populations. Some declines may represent natural variation in population size. Causes have not been determined for several cases where common species have declined over large areas. There are important considerations for ecosystem management, whether changes in amphibian populations are natural or caused by human activities. Causes for declines must be known so that management can be prescribed (or proscribed) to eliminate or minimize these causes. The natural variability of amphibian population numbers and the complexity of metapopulation structure emphasize the necessity of considering multiple temporal and spatial scales in ecosystem management. The decline of amphibian species throughout the world has received considerable recent attention (e.g., Blaustein and Wake 1990, Griffiths and Beebee 1992, Yoffe 1992). Much of this attention derives from a workshop held in February, 1990 on declining amphibians sponsored by the National Research Council Board (NRC) on Biology in Irvine, California (Barinaga 1990, Borchelt 1990). Because of media attention in the aftermath of this conference, it is a popular perception that amphibian declines are a new phenomenon that herpetologists have been slow to recognize (Griffiths and Beebee 1992, Quammen 1993). However, concern about amphibian populations in the United States dates back over 20 years. Beginning in the 1960s, a large, well-documented decline of northern leopard frogs (Rana pipiens) occurred in the

  2. Detection and Prevention of Cognitive Decline.

    PubMed

    Small, Gary W

    2016-12-01

    Current diagnostic and treatment strategies for cognitive decline can help patients maintain cognitive ability and higher levels of function longer. Despite advances in detection and early treatment strategies, many patients do not receive proper assessments and available therapies. A systematic assessment strategy will increase the likelihood of an accurate diagnosis, which can facilitate pharmacologic and non-pharmacologic treatment plans that can have a meaningful impact on prognosis. Available data support the integration of healthy lifestyle strategies in the treatment plan to help to stabilize symptoms and potentially delay future cognitive decline. While investigators continue to pursue more effective detection, treatment, and prevention strategies, the scientific data support the use of symptomatic drug treatments and recommendations for healthy lifestyle behaviors to improve quality of life and potentially stave off future cognitive decline. Success of such healthy lifestyle programs involves educating participants on the connection between lifestyle and disease prevention, offering enjoyable exercises that target the patient's skill level, and providing feedback that motivates participants to continue their healthy behaviors so they become habits.

  3. Family planning programs and fertility decline.

    PubMed

    Cuca, R

    1980-01-01

    A recently completed World Bank statistical study of family planning in 63 developing countries indicated that countries which experienced a large decline in birth rates between 1960-1977 were more likely to have a family planning program, an official population policy aimed at decreasing the birth rate, and a relatively high level of development than countries which experienced smaller or no decline in birth rates. The 65 countries represented 95% of the population of the developing world. Birth rate declines of 10% or more between 1960-1977 were experienced by: 1) 10 of the 26 countries which had a family planning program and a policy aimed at reducing the birth rate; 2) 6 of the 19 countries which had a family planning program but lacked clearly defined population objectives; and 3) 2 of the 18 countries without any population policy or program. Furthermore, the implementation of a family planning program and the adoption of a population policy were directly related to the development level of the country. This finding suggested that countries need to reach a certain level of development before they have the capacity to develop population programs and policies. When a country is sufficiently advanced to collect population data, awareness of population problems increases and they are more likely to adopt a population policy. In addition, government efficiency increases as development proceeds and governments must have a certain level of efficiency before they can implement effective programs.

  4. Reversal of cognitive decline in Alzheimer's disease

    PubMed Central

    Bredesen, Dale E.; Amos, Edwin C.; Canick, Jonathan; Ackerley, Mary; Raji, Cyrus; Fiala, Milan; Ahdidan, Jamila

    2016-01-01

    Alzheimer's disease is one of the most significant healthcare problems nationally and globally. Recently, the first description of the reversal of cognitive decline in patients with early Alzheimer's disease or its precursors, MCI (mild cognitive impairment) and SCI (subjective cognitive impairment), was published [1]. The therapeutic approach used was programmatic and personalized rather than monotherapeutic and invariant, and was dubbed metabolic enhancement for neurodegeneration (MEND). Patients who had had to discontinue work were able to return to work, and those struggling at work were able to improve their performance. The patients, their spouses, and their co-workers all reported clear improvements. Here we report the results from quantitative MRI and neuropsychological testing in ten patients with cognitive decline, nine ApoE4+ (five homozygous and four heterozygous) and one ApoE4−, who were treated with the MEND protocol for 5-24 months. The magnitude of the improvement is unprecedented, providing additional objective evidence that this programmatic approach to cognitive decline is highly effective. These results have far-reaching implications for the treatment of Alzheimer's disease, MCI, and SCI; for personalized programs that may enhance pharmaceutical efficacy; and for personal identification of ApoE genotype. PMID:27294343

  5. Ulysses orbit determination at high declinations

    NASA Technical Reports Server (NTRS)

    Mcelrath, Timothy P.; Lewis, George D.

    1995-01-01

    The trajectory of the Ulysses spacecraft caused its geocentric declination to exceed 60 deg South for over two months during the Fall of 1994, permitting continuous tracking from a single site. During this time, spacecraft operations constraints allowed only Doppler tracking data to be collected, and imposed a high radial acceleration uncertainty on the orbit determination process. The unusual aspects of this situation have motivated a re-examination of the Hamilton-Melbourne results, which have been used before to estimate the information content of Doppler tracking for trajectories closer to the ecliptic. The addition of an acceleration term to this equation is found to significantly increase the declination uncertainty for symmetric passes. In addition, a simple means is described to transform the symmetric results when the tracking pass is non-symmetric. The analytical results are then compared against numerical studies of this tracking geometry and found to be in good agreement for the angular uncertainties. The results of this analysis are applicable to the Near Earth Asteroid Rendezvous (NEAR) mission and to any other missions with high declination trajectories, as well as to missions using short tracking passes and/or one-way Doppler data.

  6. 26 CFR 1.167(b)-2 - Declining balance method.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 2 2010-04-01 2010-04-01 false Declining balance method. 1.167(b)-2 Section 1... Declining balance method. (a) Application of method. Under the declining balance method a uniform rate is... declining balance rate may be determined without resort to formula. Such rate determined under section...

  7. 26 CFR 1.167(b)-2 - Declining balance method.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 2 2014-04-01 2014-04-01 false Declining balance method. 1.167(b)-2 Section 1... Declining balance method. (a) Application of method. Under the declining balance method a uniform rate is... declining balance rate may be determined without resort to formula. Such rate determined under section...

  8. 26 CFR 1.167(b)-2 - Declining balance method.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 2 2011-04-01 2011-04-01 false Declining balance method. 1.167(b)-2 Section 1... Declining balance method. (a) Application of method. Under the declining balance method a uniform rate is... declining balance rate may be determined without resort to formula. Such rate determined under section...

  9. 26 CFR 1.167(b)-2 - Declining balance method.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 2 2013-04-01 2013-04-01 false Declining balance method. 1.167(b)-2 Section 1... Declining balance method. (a) Application of method. Under the declining balance method a uniform rate is... declining balance rate may be determined without resort to formula. Such rate determined under section...

  10. 26 CFR 1.167(b)-2 - Declining balance method.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 2 2012-04-01 2012-04-01 false Declining balance method. 1.167(b)-2 Section 1... Declining balance method. (a) Application of method. Under the declining balance method a uniform rate is... declining balance rate may be determined without resort to formula. Such rate determined under section...

  11. Antihypertensive treatments, cognitive decline, and dementia.

    PubMed

    Duron, Emmanuelle; Hanon, Olivier

    2010-01-01

    Chronic hypertension is associated with an increased risk of both vascular dementia and Alzheimer's disease (AD). In this context, the role of anti-hypertensive therapy for the prevention and delay of cognitive decline and dementia is of central importance. Most longitudinal studies have shown a significant inverse association between anti-hypertensive therapies and dementia incidence and for some of these, particularly in AD. Seven randomized, double blind placebo-controlled trials have evaluated the benefit of antihypertensive treatments on cognition. Three of them found positive results in term of prevention of dementia (SYST-EUR) or cognitive decline (PROGRESS, HOPE). Others disclosed non-significant results (MRC, SHEP, SCOPE, HYVET-COG). This discrepancy emphasizes the difficulty to perform such trials: the follow-up has to be long enough to disclose a benefit, a large number of patients is needed for these studies, and because of ethical reasons some anti-hypertensive treatments are often prescribed in the placebo group. Results of the two more recent meta-analyses are inconsistent, possibly due to methodological issues. Antihypertensive treatments could be beneficial to cognitive function by lowering blood pressure and/or by specific neuroprotective effect. Three main antihypertensive subclasses have been associated with a beneficial effect on cognitive function beyond blood pressure reduction (calcium channel blockers, angiotensin converting enzyme inhibitor, angiotensin-AT1-receptor-blockers). Further long-term randomized trials, designed especially to assess a link between antihypertensive therapy and cognitive decline or dementia are therefore needed with cognition as the primary outcome. A low blood pressure threshold that could be deleterious for cognitive function should also be determined.

  12. Multispectral sensing of citrus young tree decline

    NASA Technical Reports Server (NTRS)

    Edwards, G. J.; Ducharme, E. P.; Schehl, T.

    1975-01-01

    Computer processing of MSS data to identify and map citrus trees affected by young tree decline is analyzed. The data were obtained at 1500-feet altitude in six discrete spectral bands covering regions from 0.53 to 1.3 millimicrons as well as from instrumental ground truths of tree crowns. Measurable spectral reflectance intensity differences are observed in the leaves of healthy and diseased trees, especially at wavelengths of 500 to 600 nm and 700 to 800 nm. The overall accuracy of the method is found to be 89%.

  13. Ecological consequences of sea-ice decline.

    PubMed

    Post, Eric; Bhatt, Uma S; Bitz, Cecilia M; Brodie, Jedediah F; Fulton, Tara L; Hebblewhite, Mark; Kerby, Jeffrey; Kutz, Susan J; Stirling, Ian; Walker, Donald A

    2013-08-02

    After a decade with nine of the lowest arctic sea-ice minima on record, including the historically low minimum in 2012, we synthesize recent developments in the study of ecological responses to sea-ice decline. Sea-ice loss emerges as an important driver of marine and terrestrial ecological dynamics, influencing productivity, species interactions, population mixing, gene flow, and pathogen and disease transmission. Major challenges in the near future include assigning clearer attribution to sea ice as a primary driver of such dynamics, especially in terrestrial systems, and addressing pressures arising from human use of arctic coastal and near-shore areas as sea ice diminishes.

  14. Exercise training in obese older adults prevents increase in bone turnover and attenuates decrease in hip bone mineral density induced by weight loss despite decline in bone-active hormones.

    PubMed

    Shah, Krupa; Armamento-Villareal, Reina; Parimi, Nehu; Chode, Suresh; Sinacore, David R; Hilton, Tiffany N; Napoli, Nicola; Qualls, Clifford; Villareal, Dennis T

    2011-12-01

    0.05). In conclusion, the addition of ET to weight loss therapy among obese older adults prevents weight loss-induced increase in bone turnover and attenuates weight loss-induced reduction in hip BMD despite weight loss-induced decrease in bone-active hormones.

  15. Cognitive decline and dementia in the oldest-old.

    PubMed

    Kravitz, Efrat; Schmeidler, James; Beeri, Michal Schnaider

    2012-10-01

    The oldest-old are the fastest growing segment of the Western population. Over half of the oldest-old will have dementia, but the etiology is yet unknown. Age is the only risk factor consistently associated with dementia in the oldest-old. Many of the risk and protective factors for dementia in the young elderly, such as ApoE genotype, physical activity, and healthy lifestyle, are not relevant for the oldest-old. Neuropathology is abundant in the oldest-old brains, but specific pathologies of Alzheimer's disease (AD) or vascular dementia are not necessarily correlated with cognition, as in younger persons. It has been suggested that accumulation of both AD-like and vascular pathologies, loss of synaptic proteins, and neuronal loss contribute to the cognitive decline observed in the oldest-old. Several characteristics of the oldest-old may confound the diagnosis of dementia in this age group. A gradual age-related cognitive decline, particularly in executive function and mental speed, is evident even in non-demented oldest-old. Hearing and vision losses, which are also prevalent in the oldest-old and found in some cases to precede/predict cognitive decline, may mechanically interfere in neuropsychological evaluations. Difficulties in carrying out everyday activities, observed in the majority of the oldest-old, may be the result of motor or physical dysfunction and of neurodegenerative processes. The oldest-old appear to be a select population, who escapes major illnesses or delays their onset and duration toward the end of life. Dementia in the oldest-old may be manifested when a substantial amount of pathology is accumulated, or with a composition of a variety of pathologies. Investigating the clinical and pathological features of dementia in the oldest-old is of great importance in order to develop therapeutic strategies and to provide the most elderly of our population with good quality of life.

  16. Species decline--but why? Explanations of carabid beetle (Coleoptera, Carabidae) declines in Europe.

    PubMed

    Kotze, D Johan; O'Hara, Robert B

    2003-03-01

    We investigated some of the causes of ground beetle decline using atlas data from Belgium, Denmark and the Netherlands, countries in which natural environments have all but disappeared. We used ordinal regression to identify characteristics that are significantly correlated with the decline of carabid beetle species over the last 50-100 years, using a stepwise selection procedure to select the optimal model according to the Akaike Information Criterion. The results showed that large-bodied carabid populations have declined more than smaller ones, possibly because of their lower reproductive output and lower powers of dispersal. Habitat specialist populations (i.e. species with small niche breadths) have also decreased more than habitat generalist populations. Species with both long- and short-winged individuals have been less prone to decline than those that are exclusively either short-winged or long-winged. Dimorphic species may survive better in highly altered environments because long-winged individuals are good at dispersing between suitable habitats and short-winged individuals are good at surviving and reproducing in these newly colonised habitats. Finally, populations of large carabids associated with coastal, woodland or riparian habitat types were less prone to decline than populations of large carabids associated with various, open or grassland habitat types. The pattern is reversed for carabid species smaller than 8 mm in size. These results are explained in the context of habitat restoration and destruction in these highly modified western European countries.

  17. Catastrophic ape decline in western equatorial Africa.

    PubMed

    Walsh, Peter D; Abernethy, Kate A; Bermejo, Magdalena; Beyers, Rene; De Wachter, Pauwel; Akou, Marc Ella; Huijbregts, Bas; Mambounga, Daniel Idiata; Toham, Andre Kamdem; Kilbourn, Annelisa M; Lahm, Sally A; Latour, Stefanie; Maisels, Fiona; Mbina, Christian; Mihindou, Yves; Obiang, Sosthène Ndong; Effa, Ernestine Ntsame; Starkey, Malcolm P; Telfer, Paul; Thibault, Marc; Tutin, Caroline E G; White, Lee J T; Wilkie, David S

    2003-04-10

    Because rapidly expanding human populations have devastated gorilla (Gorilla gorilla) and common chimpanzee (Pan troglodytes) habitats in East and West Africa, the relatively intact forests of western equatorial Africa have been viewed as the last stronghold of African apes. Gabon and the Republic of Congo alone are thought to hold roughly 80% of the world's gorillas and most of the common chimpanzees. Here we present survey results conservatively indicating that ape populations in Gabon declined by more than half between 1983 and 2000. The primary cause of the decline in ape numbers during this period was commercial hunting, facilitated by the rapid expansion of mechanized logging. Furthermore, Ebola haemorrhagic fever is currently spreading through ape populations in Gabon and Congo and now rivals hunting as a threat to apes. Gorillas and common chimpanzees should be elevated immediately to 'critically endangered' status. Without aggressive investments in law enforcement, protected area management and Ebola prevention, the next decade will see our closest relatives pushed to the brink of extinction.

  18. Nutritional factors, cognitive decline, and dementia.

    PubMed

    Del Parigi, Angelo; Panza, Francesco; Capurso, Cristiano; Solfrizzi, Vincenzo

    2006-03-15

    Nutritional factors and nutritional deficiencies have been repeatedly associated with cognitive impairment. Most of the evidence is based on cross-sectional studies, which cannot prove whether a nutritional deficit is the cause or the consequence of an impaired cognitive status. In fact, cognitive impairment, in turn, can determine changes in dietary habits and consequent nutritional deficiencies. We reviewed clinical and epidemiological studies from January 1983 to June 2004. Several cross-sectional and fewer prospective studies reported an association between dietary or supplemental intake of antioxidants and protection from cognitive decline and dementia. There are negative reports as well and some methodological biases might have affected the consistencies across studies. Deficiencies of several B vitamins have been associated with cognitive dysfunction in many observational studies. More recently, deficiencies of folate (B9) and cobalamine (B12) have been studied in relation to hyperhomocysteinemia as potential determinants of cognitive impairment, dementia, and Alzheimer's disease (AD). A small number of studies assessed the association between intake of macronutrients and cognitive function or dementia. Among the others, the intake of fatty acids and cholesterol has received particular attention. Although the results are not always consistent, most studies have reported a protective role of dietary intakes of poly- and mono-unsaturated fatty acids against cognitive decline and AD. We point out that well designed intervention studies are warranted in order to establish specific levels of micro- and macronutrient deficiencies and to set general recommendations for the population.

  19. The impact of freedom on fertility decline.

    PubMed

    Campbell, Martha M; Prata, Ndola; Potts, Malcolm

    2013-01-01

    Although fertility decline often correlates with improvements in socioeconomic conditions, many demographers have found flaws in demographic transition theories that depend on changes in distal factors such as increased wealth or education. Human beings worldwide engage in sexual intercourse much more frequently than is needed to conceive the number of children they want, and for women who do not have access to the information and means they need to separate sex from childbearing, the default position is a large family. In many societies, male patriarchal drives to control female reproduction give rise to unnecessary medical rules constraining family planning (including safe abortion) or justifying child marriage. Widespread misinformation about contraception makes women afraid to adopt modern family planning. The barriers to family planning can be so deeply infused that for many women the idea of managing their fertility is not considered an option. Conversely, there is evidence that once family planning is introduced into a society, then it is normal consumer behaviour for individuals to welcome a new technology they had not wanted until it became realistically available. We contend that in societies free from child marriage, wherever women have access to a range of contraceptive methods, along with correct information and backed up by safe abortion, family size will always fall. Education and wealth can make the adoption of family planning easier, but they are not prerequisites for fertility decline. By contrast, access to family planning itself can accelerate economic development and the spread of education.

  20. The cultural evolution of fertility decline

    PubMed Central

    Colleran, Heidi

    2016-01-01

    Cultural evolutionists have long been interested in the problem of why fertility declines as populations develop. By outlining plausible mechanistic links between individual decision-making, information flow in populations and competition between groups, models of cultural evolution offer a novel and powerful approach for integrating multiple levels of explanation of fertility transitions. However, only a modest number of models have been published. Their assumptions often differ from those in other evolutionary approaches to social behaviour, but their empirical predictions are often similar. Here I offer the first overview of cultural evolutionary research on demographic transition, critically compare it with approaches taken by other evolutionary researchers, identify gaps and overlaps, and highlight parallel debates in demography. I suggest that researchers divide their labour between three distinct phases of fertility decline—the origin, spread and maintenance of low fertility—each of which may be driven by different causal processes, at different scales, requiring different theoretical and empirical tools. A comparative, multi-level and mechanistic framework is essential for elucidating both the evolved aspects of our psychology that govern reproductive decision-making, and the social, ecological and cultural contingencies that precipitate and sustain fertility decline. PMID:27022079

  1. Declining suburbs in Europe and Latin America.

    PubMed

    Audirac, Ivonne; Cunningham-Sabot, Emmanuèle; Fol, Sylvie; Moraes, Sergio Torres

    2012-01-01

    Suburban shrinkage, understood as a degenerative urban process stemming from the demise of the Fordist mode of urbanism, is generally manifested in a decline in population, industry and employment. It is also intimately linked to the global restructuring of industrial organization associated with the rise of the post-Fordist mode of urbanism and, more recently, the thrust of Asian industrialization. Framed in the discourse of industrial urbanism, this article examines the first ring of industrial suburbs that developed around large cities in their most rapid Fordist urbanization phase. These industrial suburbs, although they were formed at different times, are today experiencing specific mutations and undergoing profound restructuring on account of their particular spatial position between the central area and the expanding peripheries of the post-Fordist metropolis. This article describes and compares suburban decline in two European cities (Glasgow and Paris) and two Latin American Cities (São Paulo, Brazil and Guadalajara, Mexico), as different instances of places asymmetrically and fragmentarily integrated into the geography of globalization.

  2. Trajectory of Cognitive Decline after Incident Stroke

    PubMed Central

    Levine, Deborah A.; Galecki, Andrzej T.; Langa, Kenneth M.; Unverzagt, Frederick W.; Kabeto, Mohammed U.; Giordani, Bruno; Wadley, Virginia G.

    2015-01-01

    Importance Cognitive decline is a major cause of disability in stroke survivors. The magnitude of survivors’ cognitive changes after stroke is uncertain. Objective To measure changes in cognitive function among survivors of incident stroke, controlling for their prestroke cognitive trajectories. Design, Setting, and Participants Prospective study of 23,572 participants aged ≥45 years without baseline cognitive impairment from the Reasons for Geographic and Racial Differences in Stroke (REGARDS) cohort, residing in the continental United States, enrolled 2003–2007 and followed through March 31, 2013. Over a median follow-up of 6.1 years (25th–75th percentile: 5.0–7.1 years), 515 participants survived expert-adjudicated incident stroke and 23,057 remained stroke-free. Exposure Time-dependent incident stroke. Outcome Measures The primary outcome was change in global cognition (Six-Item Screener, SIS; range 0–6). Secondary outcomes were change in new learning (Consortium to Establish a Registry for Alzheimer’s Disease Word List Learning; range 0–30), verbal memory (Word List Delayed Recall; range 0–10), and executive function (Animal Fluency Test; range ≥0), and cognitive impairment (SIS<5/impaired vs. ≥5/unimpaired). For all tests, higher scores indicate better performance. Results Stroke was associated with acute decline in global cognition (0.10 points; 95% CI, 0.04–0.17), new learning (1.80 points; 95% CI, 0.73–2.86), and verbal memory (0.60 points; 95% CI, 0.13–1.07). Participants with stroke, compared to those without stroke, demonstrated faster declines in global cognition (0.06 points per year faster; 95% CI, 0.03–0.08) and executive function (0.63 points per year faster; 95% CI, 0.12–1.15), but not in new learning and verbal memory, compared to prestroke slopes. Among survivors, the difference in risk of cognitive impairment acutely after stroke was not statistically significant (odds ratio, 1.32; 95% CI, 0.95–1.83; P=0

  3. Shifting base-lines, declining coral cover, and the erosion of reef resilience: comment on Sweatman et al. (2011)

    NASA Astrophysics Data System (ADS)

    Hughes, T. P.; Bellwood, D. R.; Baird, A. H.; Brodie, J.; Bruno, J. F.; Pandolfi, J. M.

    2011-09-01

    Formal monitoring of the Great Barrier Reef was initiated in 1986 in response to the clear scientific evidence (and growing public concern) over the loss of corals caused by two protracted outbreaks of crown-of thorns starfish, which began in 1962 and 1979. Using monitoring data from manta tows along and across the Great Barrier Reef, Sweatman et al. (Coral Reefs 30:521-531, 2011) show that coral cover after these outbreaks declined further from 28 to 22% between 1986 and 2004. Pointing to the current levels of protection of the Great Barrier Reef, they state that earlier estimates of losses of coral cover since the early 1960s have been exaggerated. However, the loss of close to one-quarter of the coral cover over the past two decades represents an average loss of 0.34% cover per year across the whole GBR after 1986, which is very similar to previously reported rates of annual loss measured over a longer timeframe. The heaviest recent losses have occurred on inshore and mid-shelf reefs, which Sweatman et al. (Coral Reefs 30:521-531, 2011) attribute to a natural cycle of disturbance and recovery. But there has been very limited recovery. While coral cover has increased for short periods on some individual reefs, it has declined sharply on many more to produce the observed system-wide trend of declining cover. Close to 40% of coral cover on inner reefs has been lost since 1986. Of particular significance is the new evidence that coral cover has remained unchanged or declined further from a low 1986 baseline in 28 out of 29 sub-regions of the Great Barrier Reef, indicating a gradual erosion of resilience that is impeding the capacity of this huge reef system to return towards its earlier condition. This result, and other clear evidence of widespread incremental degradation from overfishing, pollution, and climate change, calls for action rather than complacency or denial.

  4. [Unhealthy lifestyles during the life course: association with physical decline in late life].

    PubMed

    Pluijm, S M F; Visser, M; Puts, M T E; Dik, M G; Schalk, B W M; van Schoor, N M; Schaap, L A; Bosscher, R J; Deeg, D J H

    2006-12-01

    This study aimed to examine the association between unhealthy lifestyle in young age, midlife and/or old age and physical decline in old age, and to examine the association between chronic exposure to an unhealthy lifestyle throughout life and physical decline in old age. The study sample included 1297 respondents of the Longitudinal Aging Study Amsterdam (LASA). Lifestyle in old age (55-85 y) was assessed at baseline, while lifestyle in young age (around 25 y) and midlife (around 40 y) were assessed retrospectively. Lifestyle factors included physical activity, body mass index (BMI), number of alcohol drinks per week and smoking. Physical decline was calculated as change in physical performance score between baseline and six-year follow-up. Of the lifestyle factors present in old age, a BMI of 25-29 vs. BMI <25 kg/m2 (odds ratio (OR) 1.6; 95% confidence interval (CI) 1.1-2.2) and a BMI of > or =30 vs. BMI <25 kg/m2 (OR 1.8; 95% CI 1.2-2.7) were associated with physical decline in old age. Being physically inactive in old age was not significantly associated with an increased risk of physical decline, however, being physically inactive both in midlife and in old age increased the odds of physical decline in old age to 1.6 (95% CI 1.1-2.4) as compared to respondents who were physically inactive in midlife and physically active in old age. Being overweight in both age periods was associated with an OR of 1.5 (95% CI 1.1-2.2). These data suggest that overweight in old age, and chronic exposure to physical inactivity or overweight throughout life increases the risk of physical decline in old age. Therefore, physical activity and prevention of overweight at all ages should be stimulated to prevent physical decline in old age.

  5. Solar Variability and the Decline of the Bubonic Plague

    NASA Astrophysics Data System (ADS)

    2001-10-01

    The bubonic plague was responsible for the deaths of a very large percentage of the population of Europe in ancient times. Leaders of state made promises to “kill off” the plague, were all unsuccessful. It wasn’t the grand promise of a politician, or some new medicinal invention that was responsible for the final decline of the plague. It appears that a chain of events that began 93,000,000 miles away from Earth exerted an impact that lead to the end of the plague’s activity. Some simple changes in solar activity that began in the early 1300’s started the final to break the stranglehold that the plague had on most of Europe. This chain of events will be presented and discussed in this paper.

  6. Widespread decline of Congo rainforest greenness in the past decade.

    PubMed

    Zhou, Liming; Tian, Yuhong; Myneni, Ranga B; Ciais, Philippe; Saatchi, Sassan; Liu, Yi Y; Piao, Shilong; Chen, Haishan; Vermote, Eric F; Song, Conghe; Hwang, Taehee

    2014-05-01

    Tropical forests are global epicentres of biodiversity and important modulators of climate change, and are mainly constrained by rainfall patterns. The severe short-term droughts that occurred recently in Amazonia have drawn attention to the vulnerability of tropical forests to climatic disturbances. The central African rainforests, the second-largest on Earth, have experienced a long-term drying trend whose impacts on vegetation dynamics remain mostly unknown because in situ observations are very limited. The Congolese forest, with its drier conditions and higher percentage of semi-evergreen trees, may be more tolerant to short-term rainfall reduction than are wetter tropical forests, but for a long-term drought there may be critical thresholds of water availability below which higher-biomass, closed-canopy forests transition to more open, lower-biomass forests. Here we present observational evidence for a widespread decline in forest greenness over the past decade based on analyses of satellite data (optical, thermal, microwave and gravity) from several independent sensors over the Congo basin. This decline in vegetation greenness, particularly in the northern Congolese forest, is generally consistent with decreases in rainfall, terrestrial water storage, water content in aboveground woody and leaf biomass, and the canopy backscatter anomaly caused by changes in structure and moisture in upper forest layers. It is also consistent with increases in photosynthetically active radiation and land surface temperature. These multiple lines of evidence indicate that this large-scale vegetation browning, or loss of photosynthetic capacity, may be partially attributable to the long-term drying trend. Our results suggest that a continued gradual decline of photosynthetic capacity and moisture content driven by the persistent drying trend could alter the composition and structure of the Congolese forest to favour the spread of drought-tolerant species.

  7. Widespread decline of Congo rainforest greenness in the past decade

    NASA Astrophysics Data System (ADS)

    Zhou, Liming; Tian, Yuhong; Myneni, Ranga B.; Ciais, Philippe; Saatchi, Sassan; Liu, Yi Y.; Piao, Shilong; Chen, Haishan; Vermote, Eric F.; Song, Conghe; Hwang, Taehee

    2014-05-01

    Tropical forests are global epicentres of biodiversity and important modulators of climate change, and are mainly constrained by rainfall patterns. The severe short-term droughts that occurred recently in Amazonia have drawn attention to the vulnerability of tropical forests to climatic disturbances. The central African rainforests, the second-largest on Earth, have experienced a long-term drying trend whose impacts on vegetation dynamics remain mostly unknown because in situ observations are very limited. The Congolese forest, with its drier conditions and higher percentage of semi-evergreen trees, may be more tolerant to short-term rainfall reduction than are wetter tropical forests, but for a long-term drought there may be critical thresholds of water availability below which higher-biomass, closed-canopy forests transition to more open, lower-biomass forests. Here we present observational evidence for a widespread decline in forest greenness over the past decade based on analyses of satellite data (optical, thermal, microwave and gravity) from several independent sensors over the Congo basin. This decline in vegetation greenness, particularly in the northern Congolese forest, is generally consistent with decreases in rainfall, terrestrial water storage, water content in aboveground woody and leaf biomass, and the canopy backscatter anomaly caused by changes in structure and moisture in upper forest layers. It is also consistent with increases in photosynthetically active radiation and land surface temperature. These multiple lines of evidence indicate that this large-scale vegetation browning, or loss of photosynthetic capacity, may be partially attributable to the long-term drying trend. Our results suggest that a continued gradual decline of photosynthetic capacity and moisture content driven by the persistent drying trend could alter the composition and structure of the Congolese forest to favour the spread of drought-tolerant species.

  8. Decline of radionuclides in Columbia River biota

    SciTech Connect

    Cushing, C.E.; Watson, D.G.; Scott, A.J.; Gurtisen, J.M.

    1980-03-01

    In January 1971, the last of nine plutonium production reactors using direct discharge of once-through cooling waters into the Columbia River was closed. Sampling was initiated at three stations on the Columbia River to document the decline of the radionuclide body burdens in the biota of the Columbia River ecosystem. The data show that in a river-reservoir complex, the measurable body burden of fission-produced radionuclides decreased to essentially undetectable levels within 18 to 24 mo after cessation of discharge of once-through cooling water into the river. On the basis of data from the free-flowing station, we believe that this decrease would be even more rapid in an unimpounded river.

  9. Global biodiversity: indicators of recent declines

    USGS Publications Warehouse

    Butchart, Stuart H.M.; Walpole, Matt; Collen, Ben; Van Strien, Arco; Scharlemann, Jorn P.W.; Almond, Rosamunde E.A.; Baillie, Jonathan E.M.; Bomhard, Bastian; Brown, Claire; Bruno, John; Carpenter, Kent E.; Carr, Genevieve M.; Chanson, Janice; Chenery, Anna M.; Csirke, Jorge; Davidson, Nick C.; Dentener, Frank; Foster, Matt; Galli, Alessandro; Galloway, James N.; Genovesi, Piero; Gregory, Richard D.; Hockings, Marc; Kapos, Valerie; Lamarque, Jean-Francois; Leverington, Fiona; Loh, Jonathan; McGeoch, Melodie A.; McRae, Louise; Minasyan, Anahit; Morcillo, Monica Hernandez; Oldfield, Thomasina E.E.; Pauly, Daniel; Quader, Suhel; Revenga, Carmen; Sauer, John R.; Skolnik, Benjamin; Spear, Dian; Stanwell-Smith, Damon; Stuart, Simon N.; Symes, Andy; Tierney, Megan; Tyrrell, Tristan D.; Vie, Jean-Christophe; Watson, Reg

    2011-01-01

    In 2002, world leaders committed, through the Convention on Biological Diversity, to achieve a significant reduction in the rate of biodiversity loss by 2010. We compiled 31 indicators to report on progress toward this target. Most indicators of the state of biodiversity (covering species' population trends, extinction risk, habitat extent and condition, and community composition) showed declines, with no significant recent reductions in rate, whereas indicators of pressures on biodiversity (including resource consumption, invasive alien species, nitrogen pollution, overexploitation, and climate change impacts) showed increases. Despite some local successes and increasing responses (including extent and biodiversity coverage of protected areas, sustainable forest management, policy responses to invasive alien species, and biodiversity-related aid), the rate of biodiversity loss does not appear to be slowing.

  10. Emergence and Decline of Scientific Paradigms

    NASA Astrophysics Data System (ADS)

    Bornholdt, S.; Jensen, M. H.; Sneppen, K.

    2011-02-01

    Scientific paradigms have a tendency to rise fast and decline slowly. This asymmetry reflects the difficulty in developing a truly original idea, compared to the ease at which a concept can be eroded by numerous modifications. Here we formulate a model for the emergence and spread of ideas which deals with this asymmetry by constraining the ability of agents to return to already abandoned concepts. The model exhibits a fairly regular pattern of global paradigm shifts, where older paradigms are eroded and subsequently replaced by new ones. The model sets the theme for a new class of pattern formation models, where local dynamics breaks the detailed balance in a way that prevents old states from defending themselves against new nucleating or invading states. The model allows for frozen events in terms of the coexistence of multiple metastable states.

  11. The decline in child mortality: a reappraisal.

    PubMed Central

    Ahmad, O. B.; Lopez, A. D.; Inoue, M.

    2000-01-01

    The present paper examines, describes and documents country-specific trends in under-five mortality rates (i.e., mortality among children under five years of age) in the 1990s. Our analysis updates previous studies by UNICEF, the World Bank and the United Nations. It identifies countries and WHO regions where sustained improvement has occurred and those where setbacks are evident. A consistent series of estimates of under-five mortality rate is provided and an indication is given of historical trends during the period 1950-2000 for both developed and developing countries. It is estimated that 10.5 million children aged 0-4 years died in 1999, about 2.2 million or 17.5% fewer than a decade earlier. On average about 15% of newborn children in Africa are expected to die before reaching their fifth birthday. The corresponding figures for many other parts of the developing world are in the range 3-8% and that for Europe is under 2%. During the 1990s the decline in child mortality decelerated in all the WHO regions except the Western Pacific but there is no widespread evidence of rising child mortality rates. At the country level there are exceptions in southern Africa where the prevalence of HIV is extremely high and in Asia where a few countries are beset by economic difficulties. The slowdown in the rate of decline is of particular concern in Africa and South-East Asia because it is occurring at relatively high levels of mortality, and in countries experiencing severe economic dislocation. As the HIV/AIDS epidemic continues in Africa, particularly southern Africa, and in parts of Asia, further reductions in child mortality become increasingly unlikely until substantial progress in controlling the spread of HIV is achieved. PMID:11100613

  12. Depressed Mood Mediates Decline in Cognitive Processing Speed in Caregivers

    ERIC Educational Resources Information Center

    Vitaliano, Peter P.; Zhang, Jianping; Young, Heather M.; Caswell, Lisa W.; Scanlan, James M.; Echeverria, Diana

    2009-01-01

    Purpose: Very few studies have examined cognitive decline in caregivers versus noncaregivers, and only 1 study has examined mediators of such decline. We evaluated the relationship between caregiver status and decline on the digit symbol test (DST; a measure of processing speed, attention, cognitive-motor translation, and visual scanning) and…

  13. The role of contaminants and pollution in species decline

    USGS Publications Warehouse

    Pattee, O.H.; Rattner, B.A.; Eisler, R.; Wegner, V.L.; Bounds, D.L.

    1999-01-01

    Members of over 1,200 taxa have been listed as Threatened or Endangered, and over 4,000 additional organisms have been identified as Candidate Species or Species of Concern. Both naturally-occurring and anthropogenic activities (e.g., environmental contaminants and pollution) have been demonstrated to be a significant factor in depressing populations or catalyzing the final crash of some species. The objective of this project is to develop a synthesis document and database that lists and ranks the presumed causes of decline, with special emphasis on contaminants and pollutant-related situations. This will be accomplished by a synoptic review of all recovery plans (n=517) with listing packages (n= 1180) serving as a secondary source of information, followed by itemization, cross-referencing, enumeration, and ranking of contributing and limiting factors. To date we have analyzed most of the available recovery plans for freshwater mussels (n=39), reptiles (n=26). and amphibians (n=6). We categorized 116 reasons fur the decline in freshwater mussels, subsuming them into 6 classes: habitat alteration/availability (44.4%);.contaminants (24.1%); pollution (18.0%); exploitation/harvest (1.7%); introduction of exotic species (2.7%); miscellaneous others (9.2%). The 171 causes of decline for reptiles can be subsumed into the same categories: habitat alteration/availability (32.7%); contaminants (6.4%); pollution (9.9%); exploitation/harvest (28.7%); introduction of exotic species (11.1%); miscellaneous others (11.1%). The 34 causes for amphibian decline fall into 5 classes: habitat alteration/availability (50.0%); contaminants (5.9%); pollution (5.9%); exploitation/harvest (5.9%); miscellaneous others (32.3%). The contaminant and pollution related causes for the decline in mussels can be attributed to four classes of alterations: water quality (47.2%); effluents/ spills (46.7%); biocides (3.3%); other toxic compounds (2.8%). For reptiles, the contamination and pollution

  14. Agriculture intensifies soil moisture decline in Northern China

    SciTech Connect

    Liu, Yaling; Pan, Zhihua; Zhuang, Qianlai; Miralles, Diego; Teuling, Adriann; Zhang, Tonglin; An, Pingli; Dong, Zhiqiang; Zhang, Jingting; He, Di; Wang, Liwei; Pan, Xuebiao; Bai, Wei; Niyogi, Dev

    2015-07-09

    Northern China is one of the most densely populated regions in the world. Agricultural activities have intensified since the 1980s to provide food security to the country. However, this intensification has likely contributed to an increasing scarcity in water resources, which may in turn be endangering food security. Based on in-situ measurements of soil moisture collected in agricultural plots during 1983–2012, we find that topsoil (0–50 cm) volumetric water content during the growing season has declined significantly (p<0.01), with a trend of -0.011 to -0.015 m3 m-3 per decade. Observed discharge declines for the three large river basins are consistent with the effects of agricultural intensification, although other factors (e.g. dam constructions) likely have contributed to these trends. Practices like fertilizer application have favoured biomass growth and increased transpiration rates, thus reducing available soil water. In addition, the rapid proliferation of water-expensive crops (e.g., maize) and the expansion of the area dedicated to food production have also contributed to soil drying. Adoption of alternative agricultural practices that can meet the immediate food demand without compromising future water resources seem critical for the sustainability of the food production system.

  15. Agriculture intensifies soil moisture decline in Northern China.

    PubMed

    Liu, Yaling; Pan, Zhihua; Zhuang, Qianlai; Miralles, Diego G; Teuling, Adriaan J; Zhang, Tonglin; An, Pingli; Dong, Zhiqiang; Zhang, Jingting; He, Di; Wang, Liwei; Pan, Xuebiao; Bai, Wei; Niyogi, Dev

    2015-07-09

    Northern China is one of the most densely populated regions in the world. Agricultural activities have intensified since the 1980s to provide food security to the country. However, this intensification has likely contributed to an increasing scarcity in water resources, which may in turn be endangering food security. Based on in-situ measurements of soil moisture collected in agricultural plots during 1983-2012, we find that topsoil (0-50 cm) volumetric water content during the growing season has declined significantly (p < 0.01), with a trend of -0.011 to -0.015 m(3) m(-3) per decade. Observed discharge declines for the three large river basins are consistent with the effects of agricultural intensification, although other factors (e.g. dam constructions) likely have contributed to these trends. Practices like fertilizer application have favoured biomass growth and increased transpiration rates, thus reducing available soil water. In addition, the rapid proliferation of water-expensive crops (e.g., maize) and the expansion of the area dedicated to food production have also contributed to soil drying. Adoption of alternative agricultural practices that can meet the immediate food demand without compromising future water resources seem critical for the sustainability of the food production system.

  16. Agriculture intensifies soil moisture decline in Northern China

    NASA Astrophysics Data System (ADS)

    Liu, Yaling; Pan, Zhihua; Zhuang, Qianlai; Miralles, Diego G.; Teuling, Adriaan J.; Zhang, Tonglin; An, Pingli; Dong, Zhiqiang; Zhang, Jingting; He, Di; Wang, Liwei; Pan, Xuebiao; Bai, Wei; Niyogi, Dev

    2015-07-01

    Northern China is one of the most densely populated regions in the world. Agricultural activities have intensified since the 1980s to provide food security to the country. However, this intensification has likely contributed to an increasing scarcity in water resources, which may in turn be endangering food security. Based on in-situ measurements of soil moisture collected in agricultural plots during 1983-2012, we find that topsoil (0-50 cm) volumetric water content during the growing season has declined significantly (p < 0.01), with a trend of -0.011 to -0.015 m3 m-3 per decade. Observed discharge declines for the three large river basins are consistent with the effects of agricultural intensification, although other factors (e.g. dam constructions) likely have contributed to these trends. Practices like fertilizer application have favoured biomass growth and increased transpiration rates, thus reducing available soil water. In addition, the rapid proliferation of water-expensive crops (e.g., maize) and the expansion of the area dedicated to food production have also contributed to soil drying. Adoption of alternative agricultural practices that can meet the immediate food demand without compromising future water resources seem critical for the sustainability of the food production system.

  17. Asparagus decline: Autotoxicity and autotoxic compounds in asparagus rhizomes.

    PubMed

    Kato-Noguchi, Hisashi; Nakamura, Keisuke; Ohno, Osamu; Suenaga, Kiyotake; Okuda, Nobuyuki

    2017-03-01

    Asparagus (Asparagus officinalis L.) is a perennial vegetable, but its crop productivity and quality decrease gradually. One possible reason for "asparagus decline" is thought to be the autotoxicity of asparagus. However, the autotoxic property of asparagus rhizomes remains unknown. The objective of this study was to determine the potential role of rhizomes in the autotoxicity of asparagus. An aqueous methanol extract of asparagus rhizomes inhibited the growth of asparagus seedlings and six other test plants in a concentration-dependent manners: garden cress (Lepidum sativum L.), lettuce (Lactuca sativa L.), alfalfa (Medicago sativa L.), ryegrass (Lolium multiflorum Lam.), timothy (Phleum pratense L.) and barnyardgrass (Echinochloa crus-galli (L.) Beauv.). These results suggest that asparagus rhizomes contain autotoxic compounds. The extract was purified through several chromatographic steps with monitoring the autotoxic activity, and p-coumaric acid and iso-agatharesinol were isolated. These compounds inhibited the shoot and root growth of asparagus and two other test plants, garden cress and ryegrass, at concentrations higher than 0.1mM. The concentrations required for 50% inhibition of the root and shoot growth of these test plants ranged from 0.36 to 0.85mM and 0.41-1.22mM for p-coumaric acid and iso-agatharesinol, respectively. Therefore, these compounds may contribute to the autotoxicity caused by asparagus rhizomes and may be involved in "asparagus decline".

  18. Cardiorespiratory Fitness and Accelerated Cognitive Decline With Aging

    PubMed Central

    2014-01-01

    Background. Growing evidence suggests that self-reported physical activity accounts for variability in cognitive function among older adults, and aerobic intervention may improve cognitive function in this population. However, much less is known about the longitudinal association between direct measures of cardiorespiratory fitness and cognitive function across the life span. The present study examined the prospective association between symptom-limited maximal oxygen consumption (VO2max) and longitudinal performance on a comprehensive neuropsychological battery. Methods. Up to 1,400 participants aged 19–94 years underwent initial VO2max assessment and completed subsequent tests of memory, attention, perceptuomotor speed, language, and executive function, in addition to cognitive screening measures, on up to six occasions (mean, M = 2; standard deviation, SD = 1) for up to 18 years (M = 7, SD = 3). Mixed-effects regression models were adjusted for demographic, biomedical, and behavioral confounders. Results. Analyses revealed significant longitudinal associations between baseline VO2max and trajectory of performance on multiple measures of verbal and visual memory, as well as on a cognitive screening test (all ps < .05). Individuals with lower VO2max demonstrated accelerated trajectories of cognitive decline over time. Conclusions. Baseline cardiorespiratory fitness is related to longitudinal neuropsychological performance, and memory appears to be a particularly vulnerable domain. Evidence that aerobic fitness is associated with accelerated cognitive decline emphasizes the possible importance of behavioral interventions to optimize cognitive aging over time. PMID:24192540

  19. Decline curve analysis of vapor-dominated reservoirs

    SciTech Connect

    Faulder, D.D.

    1997-05-01

    Geothermal Program activities at the INEEL include a review of the transient and pseudosteady state behavior of production wells in vapor-dominated systems with a focus on The Geysers field. The complicated history of development, infill drilling, injection, and declining turbine inlet pressures makes this field an ideal study area to test new techniques. The production response of a well can be divided into two distinct periods: transient flow followed by pseudo-steady state (depletion). The transient period can be analyzed using analytic equations, while the pseudo-steady state period is analyzed using empirical relationships. Yet by reviewing both periods, a great deal of insight can be gained about the well and reservoir. An example is presented where this approach is used to determine the permeability thickness product, kh, injection and production interference, and estimate the empirical Arps decline parameter b. When the production data is reinitialized (as may be required by interference effects), the kh determined from the new transient period is repeatable. This information can be used for well diagnostics, quantification of injection benefits, and the empirical estimation of remaining steam reserves.

  20. Agriculture intensifies soil moisture decline in Northern China

    DOE PAGES

    Liu, Yaling; Pan, Zhihua; Zhuang, Qianlai; ...

    2015-07-09

    Northern China is one of the most densely populated regions in the world. Agricultural activities have intensified since the 1980s to provide food security to the country. However, this intensification has likely contributed to an increasing scarcity in water resources, which may in turn be endangering food security. Based on in-situ measurements of soil moisture collected in agricultural plots during 1983–2012, we find that topsoil (0–50 cm) volumetric water content during the growing season has declined significantly (p<0.01), with a trend of -0.011 to -0.015 m3 m-3 per decade. Observed discharge declines for the three large river basins are consistentmore » with the effects of agricultural intensification, although other factors (e.g. dam constructions) likely have contributed to these trends. Practices like fertilizer application have favoured biomass growth and increased transpiration rates, thus reducing available soil water. In addition, the rapid proliferation of water-expensive crops (e.g., maize) and the expansion of the area dedicated to food production have also contributed to soil drying. Adoption of alternative agricultural practices that can meet the immediate food demand without compromising future water resources seem critical for the sustainability of the food production system.« less

  1. Agriculture intensifies soil moisture decline in Northern China

    PubMed Central

    Liu, Yaling; Pan, Zhihua; Zhuang, Qianlai; Miralles, Diego G.; Teuling, Adriaan J.; Zhang, Tonglin; An, Pingli; Dong, Zhiqiang; Zhang, Jingting; He, Di; Wang, Liwei; Pan, Xuebiao; Bai, Wei; Niyogi, Dev

    2015-01-01

    Northern China is one of the most densely populated regions in the world. Agricultural activities have intensified since the 1980s to provide food security to the country. However, this intensification has likely contributed to an increasing scarcity in water resources, which may in turn be endangering food security. Based on in-situ measurements of soil moisture collected in agricultural plots during 1983–2012, we find that topsoil (0–50 cm) volumetric water content during the growing season has declined significantly (p < 0.01), with a trend of −0.011 to −0.015 m3 m−3 per decade. Observed discharge declines for the three large river basins are consistent with the effects of agricultural intensification, although other factors (e.g. dam constructions) likely have contributed to these trends. Practices like fertilizer application have favoured biomass growth and increased transpiration rates, thus reducing available soil water. In addition, the rapid proliferation of water-expensive crops (e.g., maize) and the expansion of the area dedicated to food production have also contributed to soil drying. Adoption of alternative agricultural practices that can meet the immediate food demand without compromising future water resources seem critical for the sustainability of the food production system. PMID:26158774

  2. Declining ecosystem health and the dilution effect

    PubMed Central

    Khalil, Hussein; Ecke, Frauke; Evander, Magnus; Magnusson, Magnus; Hörnfeldt, Birger

    2016-01-01

    The “dilution effect” implies that where species vary in susceptibility to infection by a pathogen, higher diversity often leads to lower infection prevalence in hosts. For directly transmitted pathogens, non-host species may “dilute” infection directly (1) and indirectly (2). Competitors and predators may (1) alter host behavior to reduce pathogen transmission or (2) reduce host density. In a well-studied system, we tested the dilution of the zoonotic Puumala hantavirus (PUUV) in bank voles (Myodes glareolus) by two competitors and a predator. Our study was based on long-term PUUV infection data (2003–2013) in northern Sweden. The field vole (Microtus agrestis) and the common shrew (Sorex araneus) are bank vole competitors and Tengmalm’s owl (Aegolius funereus) is a main predator of bank voles. Infection probability in bank voles decreased when common shrew density increased, suggesting that common shrews reduced PUUV transmission. Field voles suppressed bank vole density in meadows and clear-cuts and indirectly diluted PUUV infection. Further, Tengmalm’s owl decline in 1980–2013 may have contributed to higher PUUV infection rates in bank voles in 2003–2013 compared to 1979–1986. Our study provides further evidence for dilution effect and suggests that owls may have an important role in reducing disease risk. PMID:27499001

  3. Update: routine screening for antibodies to human immunodeficiency virus, civilian applicants for U.S. military service and U.S. Armed Forces, active and reserve components, January 2008-June 2013.

    PubMed

    2013-08-01

    This report contains an update through June 2013 on the results of screening for HIV infection among civilian applicants for military service and among members of the active and reserve components of the Armed Forces. Among civilian applicants, annual rates of prevalence of HIV infection showed a continuing downward trend. Rates among black, non-Hispanic applicants were higher than other racial/ethnic groups but have declined sharply since 2008. Among service members, annual rates have varied by service and component, with higher rates in the Army and Navy and lower rates in the Marine Corps and Air Force. Members of the Army and Air Force Reserves have had consistently higher rates than members of their respective active components. For both civilian applicants and service members, rates among men are notably higher than among women. The possible roles of unprotected sex and pre-deployment behaviors and the associated challenges to prevention of HIV infection are discussed.

  4. Handgrip strength predicts functional decline at discharge in hospitalized male elderly: a hospital cohort study.

    PubMed

    García-Peña, Carmen; García-Fabela, Luis C; Gutiérrez-Robledo, Luis M; García-González, Jose J; Arango-Lopera, Victoria E; Pérez-Zepeda, Mario U

    2013-01-01

    Functional decline after hospitalization is a common adverse outcome in elderly. An easy to use, reproducible and accurate tool to identify those at risk would aid focusing interventions in those at higher risk. Handgrip strength has been shown to predict adverse outcomes in other settings. The aim of this study was to determine if handgrip strength measured upon admission to an acute care facility would predict functional decline (either incident or worsening of preexisting) at discharge among older Mexican, stratified by gender. In addition, cutoff points as a function of specificity would be determined. A cohort study was conducted in two hospitals in Mexico City. The primary endpoint was functional decline on discharge, defined as a 30-point reduction in the Barthel Index score from that of the baseline score. Handgrip strength along with other variables was measured at initial assessment, including: instrumental activities of daily living, cognition, depressive symptoms, delirium, hospitalization length and quality of life. All analyses were stratified by gender. Logistic regression to test independent association between handgrip strength and functional decline was performed, along with estimation of handgrip strength test values (specificity, sensitivity, area under the curve, etc.). A total of 223 patients admitted to an acute care facility between 2007 and 2009 were recruited. A total of 55 patients (24.7%) had functional decline, 23.46% in male and 25.6% in women. Multivariate analysis showed that only males with low handgrip strength had an increased risk of functional decline at discharge (OR 0.88, 95% CI 0.79-0.98, p = 0.01), with a specificity of 91.3% and a cutoff point of 20.65 kg for handgrip strength. Females had not a significant association between handgrip strength and functional decline. Measurement of handgrip strength on admission to acute care facilities may identify male elderly patients at risk of having functional decline, and intervene

  5. Handgrip Strength Predicts Functional Decline at Discharge in Hospitalized Male Elderly: A Hospital Cohort Study

    PubMed Central

    García-Peña, Carmen; García-Fabela, Luis C.; Gutiérrez-Robledo, Luis M.; García-González, Jose J.; Arango-Lopera, Victoria E.; Pérez-Zepeda, Mario U.

    2013-01-01

    Functional decline after hospitalization is a common adverse outcome in elderly. An easy to use, reproducible and accurate tool to identify those at risk would aid focusing interventions in those at higher risk. Handgrip strength has been shown to predict adverse outcomes in other settings. The aim of this study was to determine if handgrip strength measured upon admission to an acute care facility would predict functional decline (either incident or worsening of preexisting) at discharge among older Mexican, stratified by gender. In addition, cutoff points as a function of specificity would be determined. A cohort study was conducted in two hospitals in Mexico City. The primary endpoint was functional decline on discharge, defined as a 30-point reduction in the Barthel Index score from that of the baseline score. Handgrip strength along with other variables was measured at initial assessment, including: instrumental activities of daily living, cognition, depressive symptoms, delirium, hospitalization length and quality of life. All analyses were stratified by gender. Logistic regression to test independent association between handgrip strength and functional decline was performed, along with estimation of handgrip strength test values (specificity, sensitivity, area under the curve, etc.). A total of 223 patients admitted to an acute care facility between 2007 and 2009 were recruited. A total of 55 patients (24.7%) had functional decline, 23.46% in male and 25.6% in women. Multivariate analysis showed that only males with low handgrip strength had an increased risk of functional decline at discharge (OR 0.88, 95% CI 0.79–0.98, p = 0.01), with a specificity of 91.3% and a cutoff point of 20.65 kg for handgrip strength. Females had not a significant association between handgrip strength and functional decline. Measurement of handgrip strength on admission to acute care facilities may identify male elderly patients at risk of having functional decline, and

  6. Relationship Between Quality of Care and Functional Decline in Hospitalized Vulnerable Elders

    PubMed Central

    Arora, Vineet M.; Plein, Colleen; Chen, Stuart; Siddique, Juned; Sachs, Greg A.; Meltzer, David O.

    2009-01-01

    Background While process of care is a valuable dimension of quality, process-of-care-based quality indicators (POC-QIs) are ideally associated with meaningful patient outcomes. The relationship between POC-QIs for hospitalized older patients and functional decline, a relevant outcome for older patients, is unknown. Objective To assess the relationship between POC-QIs for hospitalized elders and functional decline Research Design Observational cohort study. Subjects Hospitalized vulnerable elder patients age 65 or older admitted to a general medicine inpatient service from 1 June 2004 to 1 June 2007. Measures POC-QIs received by hospitalized patients (measured by ACOVE QIs) and functional decline (increased Activities of Daily Living impairments post discharge). Results For 898 vulnerable elder patients, mean adherence to six universally applied quality indicators was 57.8%. After adjustment for factors likely associated with functional decline (comorbidity, vulnerability, baseline functional limitation, number of POC-QIs triggered, length of stay, code status, and interaction between frailty and QI adherence), there was no association between higher quality of care (using the composite score) and increased risk of functional decline. Patients who received a mobility plan were 1.48 (95% CI 1.07-2.05; p=0.017) times more likely to suffer functional decline after discharge. Patients who received an assessment of nutritional status had a lower odds of suffering functional decline after discharge (OR 0.37 (95% CI 0.21-0.64; p<0.001). Conclusions Hospitalized vulnerable elders who receive higher quality of care, as measured by ACOVE QIs, are not less likely to suffer decline after discharge. PMID:19597372

  7. How family members manage risk around functional decline: The autonomy management process in households facing dementia

    PubMed Central

    Berry, Brandon; Apesoa-Varano, Ester Carolina; Gomez, Yarin

    2015-01-01

    Most dementia research investigates the social context of declining ability through studies of decision-making around medical treatment and end-of-life care. This study seeks to fill an important gap in research about how family members manage the risks of functional decline at home. Drawing on three waves of retrospective interviewing in 2012–2014, it investigates how family members in US households manage decline in an affected individual’s natural range of daily activities over time. The findings show that early on in the study period affected individuals were perceived to have awareness of their decline and routinely drew on family members for support. Support transformed when family members detected that the individual’s deficit awareness had diminished, creating a corresponding increase in risk of self-harm around everyday activities. With a loss of confidence in the individual’s ability to regulate his or her own activities to avoid these risks, family members employed unilateral practices to manage the individual’s autonomy around his or her activity involvements. These practices typically involved various deceits and ruses to discourage elders from engaging in activities perceived as potentially dangerous. The study concludes by discussing the implications that the social context of interpretive work around awareness and risk plays an important role in how families perceive an elder’s functional ability and manage his or her activity involvements. PMID:25697634

  8. Prediction of Cognitive Decline in Healthy Older Adults using fMRI

    PubMed Central

    Woodard, John L.; Seidenberg, Michael; Nielson, Kristy A.; Smith, J. Carson; Antuono, Piero; Durgerian, Sally; Guidotti, Leslie; Zhang, Qi; Butts, Alissa; Hantke, Nathan; Lancaster, Melissa; Rao, Stephen M.

    2010-01-01

    Few studies have examined the extent to which structural and functional MRI, alone and in combination with genetic biomarkers, can predict future cognitive decline in asymptomatic elders. This prospective study evaluated individual and combined contributions of demographic information, genetic risk, hippocampal volume, and fMRI activation for predicting cognitive decline after an 18-month retest interval. Standardized neuropsychological testing, an fMRI scans semantic memory task (famous name discrimination), and structural MRI (sMRI) were performed on 78 healthy elders (73% female; mean age = 73 years, range = 65 to 88 years). Positive family history of dementia and presence of one or both apolipoprotein E (APOE) ε4 alleles occurred in 51.3% and 33.3% of the sample, respectively. Hippocampal volumes were traced from sMRI scans. At follow-up, all participants underwent a repeat neuropsychological examination. At 18 months, 27 participants (34.6%) declined by at least 1 SD on one of three neuropsychological measures. Using logistic regression, demographic variables (age, years of education, gender) and family history of dementia did not predict future cognitive decline. Greater fMRI activity, absence of an APOE ε4 allele, and larger hippocampal volume were associated with reduced likelihood of cognitive decline. The most effective combination of predictors involved fMRI brain activity and APOE ε4 status. Brain activity measured from task-activated fMRI, in combination with APOE ε4 status, was successful in identifying cognitively intact individuals at greatest risk for developing cognitive decline over a relatively brief time period. These results have implications for enriching prevention clinical trials designed to slow AD progression. PMID:20634590

  9. Conifer Decline and Mortality in Siberia

    NASA Astrophysics Data System (ADS)

    Kharuk, V.; Im, S.; Ranson, K.

    2015-12-01

    "Dark needle conifer" (DNC: Abies sibirica, Pinus sibirica and Picea obovata) decline and mortality increase were documented in Russia during recent decades. Here we analyzed causes and scale of Siberian pine and fir mortality in Altai-Sayan and Baikal Lake Regions and West Siberian Plane based on in situdata and remote sensing (QuickBird, Landsat, GRACE). Geographically, mortality began on the margins of the DNC range (i.e., within the forest-steppe and conifer-broadleaf ecotones) and on terrain features with maximal water stress risk (narrow-shaped hilltops, convex steep south facing slopes, shallow well-drained soils). Within ridges, mortality occurred mainly along mountain passes, where stands faced drying winds. Regularly mortality was observed to decrease with elevation increase with the exception of Baikal Lake Mountains, where it was minimal near the lake shore and increased with elevation (up to about 1000 m a.s.l.). Siberian pine and fir mortality followed a drying trend with consecutive droughts since the 1980s. Dendrochronology analysis showed that mortality was correlated with vapor pressure deficit increase, drought index, soil moisture decrease and occurrence of late frosts. In Baikal region Siberian pine mortality correlated with Baikal watershed meteorological variables. An impact of previous year climate conditions on the current growth was found (r2 = 0.6). Thus, water-stressed trees became sensitive to bark beetles and fungi impact (including Polygraphus proximus and Heterobasidion annosum). At present, an increase in mortality is observed within the majority of DNC range. Results obtained also showed a primary role of water stress in that phenomenon with a secondary role of bark beetles and fungi attacks. In future climate with increased drought severity and frequency Siberian pine and fir will partly disappear from its current range, and will be substituted by drought-tolerant species (e.g., Pinus silvestris, Larix sibirica).

  10. The lognormal handwriter: learning, performing, and declining

    PubMed Central

    Plamondon, Réjean; O'Reilly, Christian; Rémi, Céline; Duval, Thérésa

    2013-01-01

    The generation of handwriting is a complex neuromotor skill requiring the interaction of many cognitive processes. It aims at producing a message to be imprinted as an ink trace left on a writing medium. The generated trajectory of the pen tip is made up of strokes superimposed over time. The Kinematic Theory of rapid human movements and its family of lognormal models provide analytical representations of these strokes, often considered as the basic unit of handwriting. This paradigm has not only been experimentally confirmed in numerous predictive and physiologically significant tests but it has also been shown to be the ideal mathematical description for the impulse response of a neuromuscular system. This latter demonstration suggests that the lognormality of the velocity patterns can be interpreted as reflecting the behavior of subjects who are in perfect control of their movements. To illustrate this interpretation, we present a short overview of the main concepts behind the Kinematic Theory and briefly describe how its models can be exploited, using various software tools, to investigate these ideal lognormal behaviors. We emphasize that the parameters extracted during various tasks can be used to analyze some underlying processes associated with their realization. To investigate the operational convergence hypothesis, we report on two original studies. First, we focus on the early steps of the motor learning process as seen as a converging behavior toward the production of more precise lognormal patterns as young children practicing handwriting start to become more fluent writers. Second, we illustrate how aging affects handwriting by pointing out the increasing departure from the ideal lognormal behavior as the control of the fine motricity begins to decline. Overall, the paper highlights this developmental process of merging toward a lognormal behavior with learning, mastering this behavior to succeed in performing a given task, and then gradually

  11. Do plasma melatonin concentrations decline with age?

    NASA Technical Reports Server (NTRS)

    Zeitzer, J. M.; Daniels, J. E.; Duffy, J. F.; Klerman, E. B.; Shanahan, T. L.; Dijk, D. J.; Czeisler, C. A.

    1999-01-01

    PURPOSE: Numerous reports that secretion of the putative sleep-promoting hormone melatonin declines with age have led to suggestions that melatonin replacement therapy be used to treat sleep problems in older patients. We sought to reassess whether the endogenous circadian rhythm of plasma melatonin concentration changes with age in healthy drug-free adults. METHODS: We analyzed the amplitude of plasma melatonin profiles during a constant routine in 34 healthy drug-free older subjects (20 women and 14 men, aged 65 to 81 years) and compared them with 98 healthy drug-free young men (aged 18 to 30 years). RESULTS: We could detect no significant difference between a healthy and drug-free group of older men and women as compared to one of young men in the endogenous circadian amplitude of the plasma melatonin rhythm, as described by mean 24-hour average melatonin concentration (70 pmol/liter vs 73 pmol/liter, P = 0.97), or the duration (9.3 hours vs 9.1 hours, P = 0.43), mean (162 pmol/liter vs 161 pmol/liter, P = 0.63), or integrated area (85,800 pmol x min/liter vs 86,700 pmol x min/liter, P = 0.66) of the nocturnal peak of plasma melatonin. CONCLUSION: These results do not support the hypothesis that reduction of plasma melatonin concentration is a general characteristic of healthy aging. Should melatonin replacement therapy or melatonin supplementation prove to be clinically useful, we recommend that an assessment of endogenous melatonin be carried out before such treatment is used in older patients.

  12. Devil declines and catastrophic cascades: is mesopredator release of feral cats inhibiting recovery of the eastern quoll?

    PubMed

    Fancourt, Bronwyn A; Hawkins, Clare E; Cameron, Elissa Z; Jones, Menna E; Nicol, Stewart C

    2015-01-01

    The eastern quoll (Dasyurus viverrinus) is a medium-sized Australian marsupial carnivore that has recently undergone a rapid and severe population decline over the 10 years to 2009, with no sign of recovery. This decline has been linked to a period of unfavourable weather, but subsequent improved weather conditions have not been matched by quoll recovery. A recent study suggested another mechanism: that declines in Tasmanian devil (Sarcophilus harrisii) populations, due to the spread of the fatal Devil Facial Tumour Disease, have released feral cats (Felis catus) from competitive suppression, with eastern quoll declines linked to a subsequent increase in cat sightings. Yet current evidence of intraguild suppression among devils, cats and quolls is scant and equivocal. We therefore assessed the influences of top-down effects on abundance and activity patterns among devils, feral cats and eastern quolls. Between 2011 and 2013, we monitored four carnivore populations using longitudinal trapping and camera surveys, and performed camera surveys at 12 additional sites throughout the eastern quoll's range. We did not find evidence of a negative relationship between devil and cat abundance, nor of higher cat abundance in areas where devil populations had declined the longest. Cats did not appear to avoid devils spatially; however, there was evidence of temporal separation of cat and devil activity, with reduced separation and increasing nocturnal activity observed in areas where devils had declined the longest. Cats and quolls used the same areas, and there was no evidence that cat and quoll abundances were negatively related. Temporal overlap in observed cat and quoll activity was higher in summer than in winter, but this seasonal difference was unrelated to devil declines. We suggest that cats did not cause the recent quoll decline, but that predation of juvenile quolls by cats could be inhibiting low density quoll populations from recovering their former abundance

  13. Enigmatic declines in bird numbers in lowland forest of eastern Ecuador may be a consequence of climate change.

    PubMed

    Blake, John G; Loiselle, Bette A

    2015-01-01

    Bird populations have declined in many parts of the world but most of those declines can be attributed to effects of human activities (e.g., habitat fragmentation); declines in areas unaffected by human activities are not common. We have been sampling bird populations at an undisturbed site in lowland forest of eastern Ecuador annually since 2001 using a combination of mist nets and direct observations on two 100-ha plots. Bird numbers fluctuated on both plots during the first 8 years but did not show a consistent pattern of change. Since about 2008, numbers of birds on both plots have declined; capture rates in 2014 were ∼40% less than at the start of the study and observation rates were ∼50% less. Both understory and canopy species declined in abundance. Overall, insectivores showed the most pronounced declines but declines varied among trophic groups. The period from 2008 onward also was a period of stronger La Niña events which, at this study site, are associated with increased rainfall. The mechanism for the declines is not known but likely reflects a combination of reduced reproductive success coupled with reduced survival associated with changing climate.

  14. Enigmatic declines in bird numbers in lowland forest of eastern Ecuador may be a consequence of climate change

    PubMed Central

    Loiselle, Bette A.

    2015-01-01

    Bird populations have declined in many parts of the world but most of those declines can be attributed to effects of human activities (e.g., habitat fragmentation); declines in areas unaffected by human activities are not common. We have been sampling bird populations at an undisturbed site in lowland forest of eastern Ecuador annually since 2001 using a combination of mist nets and direct observations on two 100-ha plots. Bird numbers fluctuated on both plots during the first 8 years but did not show a consistent pattern of change. Since about 2008, numbers of birds on both plots have declined; capture rates in 2014 were ∼40% less than at the start of the study and observation rates were ∼50% less. Both understory and canopy species declined in abundance. Overall, insectivores showed the most pronounced declines but declines varied among trophic groups. The period from 2008 onward also was a period of stronger La Niña events which, at this study site, are associated with increased rainfall. The mechanism for the declines is not known but likely reflects a combination of reduced reproductive success coupled with reduced survival associated with changing climate. PMID:26339554

  15. A review of the role of contaminants in amphibian declines

    USGS Publications Warehouse

    Sparling, D.W.; Hoffman, David J.; Rattner, Barnett A.; Burton, G. Allen; Cairns, John=

    2003-01-01

    CONCLUSIONS--Although there are no published studies that demonstrate beyond all doubt that contaminants are involved in long term population declines of amphibians, there is ample evidence and reason to encourage active research and concern about effects. Many contaminants are lethal to amphibians at environmentally realistic concentrations. Acute mortality from these compounds may be difficult to detect because investigators would have to be present shortly after exposures. Chronic mortality may be masked by metapopulation phenomena so that areas that serve as population sinks may be repeatedly recolonized and difficult to identify. Metapopulation dynamics also make it more difficult to define discrete populations. Contaminants also have many sublethal effects on behavior, energetics, malformations, and diverse effects on physiological pathways which, by themselves might not lead to overt death but could alter reproduction or interact with other factors to result in gradual declines in populations. Scientific understanding of these interactions, and of the ecotoxicology of amphibians in general is far behind what is known about birds, fish, and mammals, and research is desperately needed in this area. Some specific suggestions for critically needed research include: (1) Determination of lethal concentrations of common contaminants - pesticides, PAHs, metals--under environmentally realistic conditions of light, temperature, and water chemistry. (2) Better understanding of the effects of long term (weeks, months), low- concentration exposure of persistent pesticides and stable contaminants on amphibians. (3) Development and refinement of bioindicators in amphibians to use in monitoring and screening for potential effects of contaminants in declining amphibian populations. (4) Further studies on the interaction between contaminants and disease agents including immunosuppression in amphibians. (5) Additional research on the interaction between ultraviolet radiation

  16. Pterostilbene ameliorates intracerebroventricular streptozotocin induced memory decline in rats.

    PubMed

    Naik, Bhagyashree; Nirwane, Abhijit; Majumdar, Anuradha

    2017-02-01

    There is strong evidence that mitochondrial dysfunction mediated oxidative stress results in aging and energy metabolism deficits thus playing a prime role in pathogenesis of Alzheimer's disease, neuronal death and cognitive dysfunction. Evidences accrued in empirical studies suggest the antioxidant, anticancer and anti-inflammatory activities of the phytochemical pterostilbene (PTS). PTS also exhibits favourable pharmacokinetic attributes compared to other stilbenes. Hence, in the present study, we explored the neuroprotective role of PTS in ameliorating the intracerebroventricular administered streptozotocin (STZ) induced memory decline in rats. PTS at doses of 10, 30 and 50 mg/kg, was administered orally to STZ administered Sprague-Dawley (SD) rats. The learning and memory tests, Morris water maze test and novel object recognition test were performed which revealed improved cognition on PTS treatment. Further, there was an overall improvement in brain antioxidant parameters like elevated catalase and superoxide dismutase activities, GSH levels, lowered levels of nitrites, lipid peroxides and carbonylated proteins. There was improved cholinergic transmission as evident by decreased acetylcholinesterase activities. The action of ATPases (Na(+) K(+), Ca(2+) and Mg(2+)) indicating the maintenance of cell membrane potential was also augmented. mRNA expression of battery of genes involved in cellular mitochondrial biogenesis and inflammation showed variations which extrapolate to hike in mitochondrial biogenesis and abated inflammation. The histological findings corroborated the effective role of PTS in countering STZ induced structural aberrations in brain.

  17. Oxidative stress and aberrant signaling in aging and cognitive decline

    PubMed Central

    Dröge, Wulf; Schipper, Hyman M

    2007-01-01

    Brain aging is associated with a progressive imbalance between antioxidant defenses and intracellular concentrations of reactive oxygen species (ROS) as exemplified by increases in products of lipid peroxidation, protein oxidation, and DNA oxidation. Oxidative conditions cause not only structural damage but also changes in the set points of redox-sensitive signaling processes including the insulin receptor signaling pathway. In the absence of insulin, the otherwise low insulin receptor signaling is strongly enhanced by oxidative conditions. Autophagic proteolysis and sirtuin activity, in turn, are downregulated by the insulin signaling pathway, and impaired autophagic activity has been associated with neurodegeneration. In genetic studies, impairment of insulin receptor signaling causes spectacular lifespan extension in nematodes, fruit flies, and mice. The predicted effects of age-related oxidative stress on sirtuins and autophagic activity and the corresponding effects of antioxidants remain to be tested experimentally. However, several correlates of aging have been shown to be ameliorated by antioxidants. Oxidative damage to mitochondrial DNA and the electron transport chain, perturbations in brain iron and calcium homeostasis, and changes in plasma cysteine homeostasis may altogether represent causes and consequences of increased oxidative stress. Aging and cognitive decline thus appear to involve changes at multiple nodes within a complex regulatory network. PMID:17517043

  18. Mitochondrial Aging and Physical Decline: Insights From Three Generations of Women

    PubMed Central

    Hebert, Sadie L.; Marquet-de Rougé, Perrine; Lanza, Ian R.; McCrady-Spitzer, Shelly K.; Levine, James A.; Middha, Sumit; Carter, Rickey E.; Klaus, Katherine A.; Therneau, Terry M.; Highsmith, Edward W.

    2015-01-01

    Decline in mitochondrial DNA (mtDNA) copy number, function, and accumulation of mutations and deletions have been proposed to contribute to age-related physical decline, based on cross sectional studies in genetically unrelated individuals. There is wide variability of mtDNA and functional measurements in many population studies and therefore we assessed mitochondrial function and physical function in 18 families of grandmothers, mothers, and daughters who share the same maternally inherited mtDNA sequence. A significant age-related decline in mtDNA copy number, mitochondrial protein expression, citrate synthase activity, cytochrome c oxidase content, and VO2 peak were observed. Also, a lower abundance of SIRT3, accompanied by an increase in acetylated skeletal muscle proteins, was observed in grandmothers. Muscle tissue–based full sequencing of mtDNA showed greater than 5% change in minor allele frequency over a lifetime in two locations, position 189 and 408 in the noncoding D-loop region but no changes were noted in blood cells mtDNA. The decline in oxidative capacity and muscle function with age in three generations of women who share the same mtDNA sequence are associated with a decline in muscle mtDNA copy number and reduced protein deacetylase activity of SIRT3. PMID:26297939

  19. Anthropogenically-Mediated Density Dependence in a Declining Farmland Bird

    PubMed Central

    Dunn, Jenny C.; Hamer, Keith C.; Benton, Tim G.

    2015-01-01

    Land management intrinsically influences the distribution of animals and can consequently alter the potential for density-dependent processes to act within populations. For declining species, high densities of breeding territories are typically considered to represent productive populations. However, as density-dependent effects of food limitation or predator pressure may occur (especially when species are dependent upon separate nesting and foraging habitats), high territory density may limit per-capita productivity. Here, we use a declining but widespread European farmland bird, the yellowhammer Emberiza citrinella L., as a model system to test whether higher territory densities result in lower fledging success, parental provisioning rates or nestling growth rates compared to lower densities. Organic landscapes held higher territory densities, but nests on organic farms fledged fewer nestlings, translating to a 5 times higher rate of population shrinkage on organic farms compared to conventional. In addition, when parental provisioning behaviour was not restricted by predation risk (i.e., at times of low corvid activity), nestling provisioning rates were higher at lower territory densities, resulting in a much greater increase in nestling mass in low density areas, suggesting that food limitation occurred at high densities. These findings in turn suggest an ecological trap, whereby preferred nesting habitat does not provide sufficient food for rearing nestlings at high population density, creating a population sink. Habitat management for farmland birds should focus not simply on creating a high nesting density, but also on ensuring heterogeneous habitats to provide food resources in close proximity to nesting birds, even if this occurs through potentially restricting overall nest density but increasing population-level breeding success. PMID:26431173

  20. Decline and depletion rates of oil production: a comprehensive investigation.

    PubMed

    Höök, Mikael; Davidsson, Simon; Johansson, Sheshti; Tang, Xu

    2014-01-13

    Two of the most fundamental concepts in the current debate about future oil supply are oilfield decline rates and depletion rates. These concepts are related, but not identical. This paper clarifies the definitions of these concepts, summarizes the underlying theory and empirically estimates decline and depletion rates for different categories of oilfield. A database of 880 post-peak fields is analysed to determine typical depletion levels, depletion rates and decline rates. This demonstrates that the size of oilfields has a significant influence on decline and depletion rates, with generally high values for small fields and comparatively low values for larger fields. These empirical findings have important implications for oil supply forecasting.

  1. Declinations in the Almagest: accuracy, epoch, and observers

    NASA Astrophysics Data System (ADS)

    Brandt, John C.; Zimmer, Peter; Jones, Patricia B.

    2014-11-01

    Almagest declinations attributed to Timocharis, Aristyllos, Hipparchus, and Ptolemy are investigated through comparisons of the reported declinations with the declinations computed from modern positions translated to the earlier epochs. Consistent results indicate an observational accuracy of ≈ 0.1° and epochs of: Timocharis, c. 298 BC; Aristyllos, c. 256 BC, and Hipparchus, c. 128 BC.The ≈ 42-year difference between Aristyllos and Timocharis is confirmed to be statistically significant. The declinations attributed to Ptolemy were likely two distinct groups—observations taken c. AD 57 and observations taken c. AD 128. The later observations could have been taken by Ptolemy himself.

  2. What's behind the Good News: The Decline in Teen Pregnancy Rates during the 1990s.

    ERIC Educational Resources Information Center

    Flanigan, Christine

    Noting that rates of teen pregnancies and births have declined over the past decade, this analysis examined how much of the progress is due to fewer teens having sex and how much to lower rates of pregnancy among sexually active teens. The analysis drew on data from the federal government's National Survey of Family Growth (NSFG), a large,…

  3. Explaining the Decline in Teen Labor Force Participation. Chicago Fed Letter. Number 234

    ERIC Educational Resources Information Center

    Aaronson, Daniel; Park, Kyung-Hong; Sullivan, Daniel

    2007-01-01

    Fewer teenagers are participating in the labor force today than at any point since WWII. At just under 44 percent teen labor force participation is 15 percentage points below its peak in the late 1970s. The authors investigate the long-run decline in the work activity of young adults, and the acceleration of this trend during the last five years.…

  4. MDS-Based State Medicaid Reimbursement and the ADL-Decline Quality Indicator

    ERIC Educational Resources Information Center

    Bellows, Nicole M.; Halpin, Helen A.

    2008-01-01

    Purpose: We examined the relationship between the quality indicator for decline in activities of daily living (ADL) and the use of the Minimum Data Set (MDS) for determining Medicaid skilled nursing facility reimbursement. Design and Methods: We conducted a cross-sectional analysis using the 2004 National MDS Facility Quality Indicator reports as…

  5. Declining Use of Wild Resources by Indigenous Peoples of the Ecuadorian Amazon

    PubMed Central

    Gray, Clark L.; Bozigar, Matthew; Bilsborrow, Richard E.

    2015-01-01

    Wild product harvesting by forest-dwelling peoples, including hunting, fishing, forest product collection and timber harvesting, is believed to be a major threat to the biodiversity of tropical forests worldwide. Despite this threat, few studies have attempted to quantify these activities across time or across large spatial scales. We use a unique longitudinal household survey (n = 480) to describe changes in these activities over time in 32 indigenous communities from five ethnicities in the northern Ecuadorian Amazon. To provide insight into the drivers of these changes, we also estimate multilevel statistical models of these activities as a function of household and community characteristics. These analyses reveal that participation in hunting, fishing, and forest product collection is high but declining across time and across ethnicities, with no evidence for a parallel decline in resource quality. However, participation in timber harvesting did not significantly decline and there is evidence of a decline in resource quality. Multilevel statistical models additionally reveal that household and community characteristics such as ethnicity, demographic characteristics, wealth, livelihood diversification, access to forest, participation in conservation programs and exposure to external markets are significant predictors of wild product harvesting. These characteristics have changed over time but cannot account for declining participation in resource harvesting. This finding suggests that participation is declining due to changes in the regional-scale social and economic context, including urbanization and the expansion of government infrastructure and services. The lesson for conservationists is that macro-scale social and economic conditions can drive reductions in wild product harvesting even in the absence of successful conservation interventions. PMID:25620805

  6. Leading an Entrepreneurial Workforce: Development or Decline?

    ERIC Educational Resources Information Center

    Clargo, Paul; Tunstall, Richard

    2011-01-01

    Purpose: This paper analyses entrepreneurial activity within existing organisations. Research tends to limit entrepreneurial behaviour to owner-managers, corporate senior and middle managers and frequently presents intrapreneurship as a positive phenomenon. This paper seeks to broaden the focus of studies of intrapreneurship and corporate…

  7. CEREBRAL ATROPHY, APOLIPOPROTEIN E ε4, AND RATE OF DECLINE IN EVERYDAY FUNCTION AMONG PATIENTS WITH AMNESTIC MILD COGNITIVE IMPAIRMENT

    PubMed Central

    Okonkwo, Ozioma C.; Alosco, Michael L.; Jerskey, Beth A.; Sweet, Lawrence H.; Ott, Brian R.; Tremont, Geoffrey

    2010-01-01

    BACKGROUND Patients with amnestic mild cognitive impairment (MCI) demonstrate decline in everyday function. In this study, we investigated whether whole brain atrophy and apolipoprotein E (APOE) genotype are associated with the rate of functional decline in MCI. METHODS Participants were 164 healthy controls, 258 MCI patients, and 103 patients with mild Alzheimer’s disease (AD), enrolled in the Alzheimer’s Disease Neuroimaging Initiative (ADNI). They underwent brain MRI scans, APOE genotyping, and completed up to 6 biannual Functional Activities Questionnaire (FAQ) assessments. Random effects regressions were used to examine trajectories of decline in FAQ across diagnostic groups, and to test the effects of ventricle-to-brain ratio (VBR) and APOE genotype on FAQ decline among MCI patients. RESULTS Rate of decline in FAQ among MCI patients was intermediate between that of controls and mild AD patients. Patients with MCI who converted to mild AD declined faster than those who remained stable. Among MCI patients, increased VBR and possession of any APOE ε4 allele were associated with faster rate of decline in FAQ. In addition, there was a significant VBR by APOE ε4 interaction such that patients who were APOE ε4 positive and had increased atrophy experienced the fastest decline in FAQ. CONCLUSIONS Functional decline occurs in MCI, particularly among patients who progress to mild AD. Brain atrophy and APOE ε4 positivity are associated with such declines, and patients who have elevated brain atrophy and are APOE ε4 positive are at greatest risk of functional degradation. These findings highlight the value of genetic and volumetric MRI information as predictors of functional decline, and thus disease progression, in MCI. PMID:20813341

  8. Does Child Labor Decline with Improving Economic Status?

    ERIC Educational Resources Information Center

    Edmonds, Eric V.

    2005-01-01

    The rapid economic growth of Vietnam provides an interesting insight into the sharp decline in child labor. A study of the rising economic status of the population across Vietnam shows that children returned to school or stopped working as their family incomes grew. The decline in child labor is steep in poor households as they emerged from…

  9. AMPHIBIAN DECLINE, ULTRAVIOLET RADIATION AND LOCAL POPULATION ADAPTATION

    EPA Science Inventory

    Amphibian population declines have been noted on both local and global scales. Causes for these declines are unknown although many hypotheses have been offered. In areas adjacent to human development, loss of habitat is a fairly well accepted cause. However in isolated, seemingl...

  10. Management of anthurium decline caused by Radopholus similis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Anthurium decline is a chronic problem in anthurium production in Hawaii. Anthurium decline has worsened with the removal of fenamiphos from the market. Growers need environmentally sound post-plant treatments to augment preplant management tactics. Avermectin (Avid, monthly), thiophanate-methyl (Cl...

  11. The Decline of the Adult School Movement between the Wars

    ERIC Educational Resources Information Center

    Freeman, Mark

    2010-01-01

    This article considers the decline of the adult school movement, one of the largest voluntary movements in the history of adult education, and critically examines some of the reasons that have been used to explain it. It explores various features of the decline, using records of selected adult schools, and discussing variations by region and…

  12. Did the Decline in Social Connections Depress Americans' Happiness?

    ERIC Educational Resources Information Center

    Bartolini, Stefano; Bilancini, Ennio; Pugno, Maurizio

    2013-01-01

    During the last 30 years US citizens experienced, on average, a decline in reported happiness, social connections, and confidence in institutions. We show that a remarkable portion of the decrease in happiness is predicted by the decline in social connections and confidence in institutions. We carry out our investigation in three steps. First, we…

  13. 34 CFR 303.405 - Parent right to decline service.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 34 Education 2 2011-07-01 2010-07-01 true Parent right to decline service. 303.405 Section 303.405... TODDLERS WITH DISABILITIES Procedural Safeguards General § 303.405 Parent right to decline service. The parents of a child eligible under this part may determine whether they, their child, or other...

  14. 34 CFR 303.405 - Parent right to decline service.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 34 Education 2 2010-07-01 2010-07-01 false Parent right to decline service. 303.405 Section 303... TODDLERS WITH DISABILITIES Procedural Safeguards General § 303.405 Parent right to decline service. The parents of a child eligible under this part may determine whether they, their child, or other...

  15. Declining Coral Calcification on the Great Barrier Reef

    NASA Astrophysics Data System (ADS)

    De'ath, Glenn; Lough, Janice M.; Fabricius, Katharina E.

    2009-01-01

    Reef-building corals are under increasing physiological stress from a changing climate and ocean absorption of increasing atmospheric carbon dioxide. We investigated 328 colonies of massive Porites corals from 69 reefs of the Great Barrier Reef (GBR) in Australia. Their skeletal records show that throughout the GBR, calcification has declined by 14.2% since 1990, predominantly because extension (linear growth) has declined by 13.3%. The data suggest that such a severe and sudden decline in calcification is unprecedented in at least the past 400 years. Calcification increases linearly with increasing large-scale sea surface temperature but responds nonlinearly to annual temperature anomalies. The causes of the decline remain unknown; however, this study suggests that increasing temperature stress and a declining saturation state of seawater aragonite may be diminishing the ability of GBR corals to deposit calcium carbonate.

  16. Preventing age-related decline of gut compartmentalization limits microbiota dysbiosis and extends lifespan

    PubMed Central

    Li, Hongjie; Qi, Yanyan; Jasper, Heinrich

    2016-01-01

    Summary Compartmentalization of the gastrointestinal (GI) tract of metazoans is critical for health. GI compartments contain specific microbiota, and microbiota dysbiosis is associated with intestinal dysfunction. Dysbiosis develops in aging intestines, yet how this relates to changes in GI compartmentalization remains unclear. The Drosophila GI tract is an accessible model to address this question. Here we show that the stomach-like copper cell region (CCR) in the middle midgut controls distribution and composition of the microbiota. We find that chronic activation of JAK/Stat signaling in the aging gut induces a metaplasia of the gastric epithelium, CCR decline, and subsequent commensal dysbiosis and epithelial dysplasia along the GI tract. Accordingly, inhibition of JAK/Stat signaling in the CCR specifically prevents age-related metaplasia, commensal dysbiosis and functional decline in old guts, and extends lifespan. Our results establish a mechanism by which age-related chronic inflammation causes the decline of intestinal compartmentalization and microbiota dysbiosis, limiting lifespan. PMID:26867182

  17. Ecosystem properties and forest decline in contrasting long-term chronosequences.

    PubMed

    Wardle, David A; Walker, Lawrence R; Bardgett, Richard D

    2004-07-23

    During succession, ecosystem development occurs; but in the long-term absence of catastrophic disturbance, a decline phase eventually follows. We studied six long-term chronosequences, in Australia, Sweden, Alaska, Hawaii, and New Zealand; for each, the decline phase was associated with a reduction in tree basal area and an increase in the substrate nitrogen-to-phosphorus ratio, indicating increasing phosphorus limitation over time. These changes were often associated with reductions in litter decomposition rates, phosphorus release from litter, and biomass and activity of decomposer microbes. Our findings suggest that the maximal biomass phase reached during succession cannot be maintained in the long-term absence of major disturbance, and that similar patterns of decline occur in forested ecosystems spanning the tropical, temperate, and boreal zones.

  18. Preventing Age-Related Decline of Gut Compartmentalization Limits Microbiota Dysbiosis and Extends Lifespan.

    PubMed

    Li, Hongjie; Qi, Yanyan; Jasper, Heinrich

    2016-02-10

    Compartmentalization of the gastrointestinal (GI) tract of metazoans is critical for health. GI compartments contain specific microbiota, and microbiota dysbiosis is associated with intestinal dysfunction. Dysbiosis develops in aging intestines, yet how this relates to changes in GI compartmentalization remains unclear. The Drosophila GI tract is an accessible model to address this question. Here we show that the stomach-like copper cell region (CCR) in the middle midgut controls distribution and composition of the microbiota. We find that chronic activation of JAK/Stat signaling in the aging gut induces a metaplasia of the gastric epithelium, CCR decline, and subsequent commensal dysbiosis and epithelial dysplasia along the GI tract. Accordingly, inhibition of JAK/Stat signaling in the CCR specifically prevents age-related metaplasia, commensal dysbiosis and functional decline in old guts, and extends lifespan. Our results establish a mechanism by which age-related chronic inflammation causes the decline of intestinal compartmentalization and microbiota dysbiosis, limiting lifespan.

  19. National Survey of Geriatricians to Define Functional Decline in Elderly People with Minor Trauma

    PubMed Central

    Abdulaziz, Kasim; Perry, Jeffrey J.; Taljaard, Monica; Émond, Marcel; Lee, Jacques S.; Wilding, Laura; Sirois, Marie-Josée; Brehaut, Jamie

    2016-01-01

    Background This study was designed to determine a clinically significant point drop in function to define functional decline and the required sensitivity for a clinical decision tool to identify elderly patients at high risk of functional decline following a minor injury. Methods After a rigorous development process, a survey questionnaire was administered to a random sample of 178 geriatricians selected from those registered in a national medical directory. The surveys were distributed using a modified Dillman technique. Results We obtained a satisfactory response rate of 70.5%. Ninety percent of the geriatricians required a sensitivity of 90% or less for a clinical decision tool to identify injured seniors at high risk of functional decline 6 months post injury. Our results indicate that 90% of the respondents considered a drop in function of at least 2 points in activities of daily living (ADL) as clinically significant when considering all 14 ADL items. Considering only the 7 basic ADL items, 90% of physicians considered a 1 point drop as clinically significant. Conclusions A tool with a sensitivity of 90% to detect patients at risk of functional decline at 6 months post minor injury would meet or exceed the sensitivity required by 90% of geriatric specialists. These findings clearly define what is a clinically significant decline following a “minor injury.” PMID:27076859

  20. Explaining the Decline in Mexico-U.S. Migration: The Effect of the Great Recession

    PubMed Central

    Villarreal, Andrés

    2014-01-01

    The rate of Mexico-U.S. migration has declined precipitously in recent years. From 25 migrants per thousand in 2005, the annual international migration rate for Mexican men dropped to 7 per thousand by 2012. If sustained, this low migration rate is likely to have a profound effect on the ethnic and national-origin composition of the U.S. population. This study examines the origins of the migration decline using a nationally representative panel survey of Mexican households. The results support an explanation that attributes a large part of the decline to lower labor demand for Mexican immigrants in the United States. Decreases in labor demand in industrial sectors that employ a large percentage of Mexican-born workers, such as construction, are found to be strongly associated with lower rates of migration for Mexican men. Second, changes in migrant selectivity are also consistent with an economic explanation for the decline in international migration. The largest declines in migration occurred precisely among the demographic groups most affected by the Great Recession: namely, economically active young men with low education. Results from the statistical analysis also show that the reduction in labor demand in key sectors of the U.S. economy resulted in a more positive educational selectivity of young migrants. PMID:25407844

  1. Endurance running program reverses the age related declines in peak oxygen consumption

    SciTech Connect

    Cartee, G.D.; Farrar, R.P.

    1986-03-01

    This study was designed to determine whether aging per se produces a decline in peak oxygen consumption (peak VO/sub 2/) or whether that decline may be due to the documented reduction in spontaneous activity. Male F344 rats, at the initial ages of 4 and 18 mos. of age, were divided into trained and untrained groups (YUT, YT, OUT, and OT). The trained groups ran up to 60 min/day 5 days/wk at a speed of 20m/min for 6 mos. The OUT rats demonstrated a 12% decline in peak VO/sub 2/ when compared to YUT rats. The OT rats had the same peak VO/sub 2/ as the YUT, but a 13% lower peak VO/sub 2/ than the YT. Representative enzymes of the TCA cycle, B oxidation, and electron transport system from gastrocnemius homogenates all declined in the OUT compared to YUT (14 to 24%). /sup 14/C-palmitate oxidation declined 45% in the OUT gastrocnemius compared to YUT. The carnitine values of the OUT were not significantly lower than the YUT and could not account for the large depression in palmitate oxidation. In contrast to the peak VO/sub 2/ which increased in OT only up to YUT values, the oxidative capacity of the skeletal muscle of OT was increased above the YUT group values equal to those of YT.

  2. Determinants of VO2 max decline with aging: an integrated perspective.

    PubMed

    Betik, Andrew C; Hepple, Russell T

    2008-02-01

    Aging is associated with a progressive decline in the capacity for physical activity. Central to this decline is a reduction in the maximal rate of oxygen utilization, or VO2 max. This critical perspective examines the roles played by the factors that determine the rate of muscle oxygen delivery versus those that determine the utilization of oxygen by muscle as a means of probing the reasons for VO2 max decline with aging. Reductions in muscle oxygen delivery, principally due to reduced cardiac output and perhaps also a maldistribution of cardiac output, appear to play the dominant role up until late middle age. On the other hand, there is a decline in skeletal muscle oxidative capacity with aging, due in part to mitochondrial dysfunction, which appears to play a particularly important role in extreme old age (senescence) where skeletal muscle VO2 max is observed to decline by approximately 50% even under conditions of similar oxygen delivery as young adult muscle. It is noteworthy that at least the structural aspects of the capillary bed do not appear to be reduced in a manner that would compromise the capacity for muscle oxygen diffusion even in senescence.

  3. Recent fertility declines in China and India: a comparative view.

    PubMed

    Kulkarni, P M; Rani, S

    1995-12-01

    This paper compares fertility transitions in China and parts of India. It is argued that China experienced a more rapid and more "impressive" decline than that of India. Socioeconomic conditions in China were more conducive to fertility decline. Kerala State in India experienced a similar decline as China but at a slower pace. The birth control campaign in China is credited with an important role in speeding the transition. It is posited that the political and administrative system and economic conditions in India are not compatible with the Chinese style program strategies. Both countries had similar fertility levels in the immediate post-revolutionary period. The most rapid decline occurred during the 1970s in China. The fertility transition was almost completed by 1981. In India, the total fertility rate (TFR) declined by only 1 point between the 1950s and 1981. In China TFR declined over 3 points during 1970-81. 76.7% of the decline in China during 1970-81 is attributed to a marked decline in marital fertility in all age groups, with the exception of ages 15-19 years. The decline in India is attributed to the decline in marital fertility. Female age at marriage rose in India, but less "impressively." In 1981 the mean age at marriage in India was 18.4 years, but it was 22.8 years in China. Marital fertility among women aged older than 30 years was considerably lower in China. Both countries experienced an increase in literacy, but in China the level of literacy was much greater. Both countries faced food shortages, but China improved food availability and calorie consumption per capita. Health services also improved in both countries, but the Chinese system of "barefoot" doctors brought services with easier reach of rural populations. Political structures differed in their dominance and organization. Family planning programs were introduced earlier in India, but prevalence was 64.4% in China in 1981 and about 22% in India.

  4. Decline in relative abundance of bottlenose dolphins exposed to long-term disturbance.

    PubMed

    Bejder, Lars; Samuels, Amy; Whitehead, Hal; Gales, Nick; Mann, Janet; Connor, Richard; Heithaus, Mike; Watson-Capps, Jana; Flaherty, Cindy; Krützen, Michael

    2006-12-01

    Studies evaluating effects of human activity on wildlife typically emphasize short-term behavioral responses from which it is difficult to infer biological significance or formulate plans to mitigate harmful impacts. Based on decades of detailed behavioral records, we evaluated long-term impacts of vessel activity on bottlenose dolphins (Tursiops sp.) in Shark Bay, Australia. We compared dolphin abundance within adjacent 36-km2 tourism and control sites, over three consecutive 4.5-year periods wherein research activity was relatively constant but tourism levels increased from zero, to one, to two dolphin-watching operators. A nonlinear logistic model demonstrated that there was no difference in dolphin abundance between periods with no tourism and periods in which one operator offered tours. As the number of tour operators increased to two, there was a significant average decline in dolphin abundance (14.9%; 95% CI=-20.8 to -8.23), approximating a decline of one per seven individuals. Concurrently, within the control site, the average increase in dolphin abundance was not significant (8.5%; 95% CI=-4.0 to +16.7). Given the substantially greater presence and proximity of tour vessels to dolphins relative to research vessels, tour-vessel activity contributed more to declining dolphin numbers within the tourism site than research vessels. Although this trend may not jeopardize the large, genetically diverse dolphin population of Shark Bay, the decline is unlikely to be sustainable for local dolphin tourism. A similar decline would be devastating for small, closed, resident, or endangered cetacean populations. The substantial effect of tour vessels on dolphin abundance in a region of low-level tourism calls into question the presumption that dolphin-watching tourism is benign.

  5. The Gulf: a young sea in decline.

    PubMed

    Sheppard, Charles; Al-Husiani, Mohsen; Al-Jamali, F; Al-Yamani, Faiza; Baldwin, Rob; Bishop, James; Benzoni, Francesca; Dutrieux, Eric; Dulvy, Nicholas K; Durvasula, Subba Rao V; Jones, David A; Loughland, Ron; Medio, David; Nithyanandan, M; Pilling, Graham M; Polikarpov, Igor; Price, Andrew R G; Purkis, Sam; Riegl, Bernhard; Saburova, Maria; Namin, Kaveh Samimi; Taylor, Oliver; Wilson, Simon; Zainal, Khadija

    2010-01-01

    This review examines the substantial changes that have taken place in marine habitats and resources of the Gulf over the past decade. The habitats are especially interesting because of the naturally high levels of temperature and salinity stress they experience, which is important in a changing world climate. However, the extent of all natural habitats is changing and their condition deteriorating because of the rapid development of the region and, in some cases from severe, episodic warming episodes. Major impacts come from numerous industrial, infrastructure-based, and residential and tourism development activities, which together combine, synergistically in some cases, to cause the observed deterioration in most benthic habitats. Substantial sea bottom dredging for material and its deposition in shallow water to extend land or to form a basis for huge developments, directly removes large areas of shallow, productive habitat, though in some cases the most important effect is the accompanying sedimentation or changes to water flows and conditions. The large scale of the activities compared to the relatively shallow and small size of the water body is a particularly important issue. Important from the perspective of controlling damaging effects is the limited cross-border collaboration and even intra-country collaboration among government agencies and large projects. Along with the accumulative nature of impacts that occur, even where each project receives environmental assessment or attention, each is treated more or less alone, rarely in combination. However, their combination in such a small, biologically interacting sea exacerbates the overall deterioration. Very few similar areas exist which face such a high concentration of disturbance, and the prognosis for the Gulf continuing to provide abundant natural resources is poor.

  6. Healthy eating and reduced risk of cognitive decline

    PubMed Central

    Dehghan, Mahshid; O'Donnell, Martin; Anderson, Craig; Teo, Koon; Gao, Peggy; Sleight, Peter; Dagenais, Gilles; Probstfield, Jeffrey L.; Mente, Andrew; Yusuf, Salim

    2015-01-01

    Objective: We sought to determine the association of dietary factors and risk of cognitive decline in a population at high risk of cardiovascular disease. Methods: Baseline dietary intake and measures of the Mini-Mental State Examination were recorded in 27,860 men and women who were enrolled in 2 international parallel trials of the ONTARGET (Ongoing Telmisartan Alone and in Combination with Ramipril Global Endpoint Trial) and TRANSCEND (Telmisartan Randomised Assessment Study in ACE Intolerant Subjects with Cardiovascular Disease) studies. We measured diet quality using the modified Alternative Healthy Eating Index. Cox proportional hazards regression was used to determine the association between diet quality and risk of ≥3-point decline in Mini-Mental State Examination score, and reported as hazard ratio with 95% confidence intervals with adjustment for covariates. Results: During 56 months of follow-up, 4,699 cases of cognitive decline occurred. We observed lower risk of cognitive decline among those in the healthiest dietary quintile of modified Alternative Healthy Eating Index compared with lowest quintile (hazard ratio 0.76, 95% confidence interval 0.66–0.86, Q5 vs Q1). Lower risk of cognitive decline was consistent regardless of baseline cognitive level. Conclusion: We found that higher diet quality was associated with a reduced risk of cognitive decline. Improved diet quality represents an important potential target for reducing the global burden of cognitive decline. PMID:25948720

  7. Tree decline and the future of Australian farmland biodiversity.

    PubMed

    Fischer, Joern; Zerger, Andre; Gibbons, Phil; Stott, Jenny; Law, Bradley S

    2010-11-09

    Farmland biodiversity is greatly enhanced by the presence of trees. However, farmland trees are declining worldwide, including in North America, Central America, and parts of southern Europe. We show that tree decline and its likely consequences are particularly severe in Australia's temperate agricultural zone, which is a threatened ecoregion. Using field data on trees, remotely sensed imagery, and a demographic model for trees, we predict that by 2100, the number of trees on an average farm will contract to two-thirds of its present level. Statistical habitat models suggest that this tree decline will negatively affect many currently common animal species, with predicted declines in birds and bats of up to 50% by 2100. Declines were predicted for 24 of 32 bird species modeled and for all of six bat species modeled. Widespread declines in trees, birds, and bats may lead to a reduction in economically important ecosystem services such as shade provision for livestock and pest control. Moreover, many other species for which we have no empirical data also depend on trees, suggesting that fundamental changes in ecosystem functioning are likely. We conclude that Australia's temperate agricultural zone has crossed a threshold and no longer functions as a self-sustaining woodland ecosystem. A regime shift is occurring, with a woodland system deteriorating into a treeless pasture system. Management options exist to reverse tree decline, but new policy settings are required to encourage their widespread adoption.

  8. Tree decline and the future of Australian farmland biodiversity

    PubMed Central

    Fischer, Joern; Zerger, Andre; Gibbons, Phil; Stott, Jenny; Law, Bradley S.

    2010-01-01

    Farmland biodiversity is greatly enhanced by the presence of trees. However, farmland trees are declining worldwide, including in North America, Central America, and parts of southern Europe. We show that tree decline and its likely consequences are particularly severe in Australia's temperate agricultural zone, which is a threatened ecoregion. Using field data on trees, remotely sensed imagery, and a demographic model for trees, we predict that by 2100, the number of trees on an average farm will contract to two-thirds of its present level. Statistical habitat models suggest that this tree decline will negatively affect many currently common animal species, with predicted declines in birds and bats of up to 50% by 2100. Declines were predicted for 24 of 32 bird species modeled and for all of six bat species modeled. Widespread declines in trees, birds, and bats may lead to a reduction in economically important ecosystem services such as shade provision for livestock and pest control. Moreover, many other species for which we have no empirical data also depend on trees, suggesting that fundamental changes in ecosystem functioning are likely. We conclude that Australia's temperate agricultural zone has crossed a threshold and no longer functions as a self-sustaining woodland ecosystem. A regime shift is occurring, with a woodland system deteriorating into a treeless pasture system. Management options exist to reverse tree decline, but new policy settings are required to encourage their widespread adoption. PMID:20974946

  9. Flavonol Intake and Cognitive Decline in Middle-Aged Adults.

    PubMed

    Root, Martin; Ravine, Erin; Harper, Anne

    2015-12-01

    Cognitive decline occurs with age and may be slowed by dietary measures, including increased intake of dietary phytochemicals. However, evidence from large and long-term studies of flavonol intake is limited. Dietary intakes of flavonols were assessed from a large biracial study of 10,041 subjects, aged 45-64, by analysis of a food frequency questionnaire administered at visit 1 of triennial visits. Cognitive function was assessed at visits 2 and 4 with the following three cognitive performance tests: the delayed word recall test, the revised Wechsler Adult Intelligence Scale digit symbol subtest, and the word fluency test of the Multilingual Aphasia Examination. The change in each score over 6 years was calculated, and a combined standardized change score was calculated. Generalized linear models controlled for age, ethnicity, gender, education level, energy intake, current smoking, physical activity, body mass index, diabetes, and vitamin C intake. Total flavonols across quintiles of intake were positively associated with preserved combined cognitive function (P<.001). This pattern with preserved combined cognitive function was consistent for the three major individual flavonols in the diet, myricetin, kaempferol, and quercetin (each P<.001). The positive association with total flavonols was strongest for the digit symbol subtest (P<.001). In this cohort, flavonol intake was correlated with protected cognitive function over time.

  10. Call to reverse decline in ODA.

    PubMed

    1997-01-01

    In November 1997, the UN Secretary-General noted that population assistance was a development success story that has resulted in increased life expectancy, child survival, and use of family planning as well as decreased maternal mortality, family size, and population growth. Despite this success, development activities are at a critical juncture because official development assistance has dropped to its lowest level. The financial target agreed upon at the 1994 International Conference on Population and Development called for $5.7 billion from donors, yet donors are committing only a small percentage of official development assistance to population programs. The income of the UN Population Fund will drop 8-10% for 1997 with the result that critical demands for reproductive health care will not be met. Because this will have critical consequences beyond the population field, the Secretary-General appealed to all nations to contribute to the highest level possible. In response to this statement, a Japanese newspaper asked why the Japanese government had cut donations by as much as 40% and urged the government to reconsider its reductions in donations to the UN.

  11. Cognition enhancers in age-related cognitive decline.

    PubMed

    Riedel, W J; Jolles, J

    1996-04-01

    A review of recently published studies on the effect of cognition enhancers in non-demented human study participants is presented. The heterogeneity of the therapeutic target, age-associated cognitive decline, can be improved by separately treating groups in whom age-extrinsic factors may underlie cognitive pathology. Standardisation of cognitive assessments is necessary, since many different tests are applied to answer the same question. Modelling cognitive dysfunction, either by pharmacological or nonpharmacological means, in humans is highly recommended since it allows hypotheses to be tested in a clearly operationalised way. Predictive validity of the currently applied models for the clinical situation remains a problem, however. The scopolamine (hyoscine) model has, to a reasonable extent, predictive validity for the cholinergic agents. The results of 67 single-dose studies and 30 multiple-dose studies are summarised. All single-dose studies and 14 multiple-dose studies were carried out in young or elderly human volunteers. In 45 of 81 volunteer studies, models of cognitive dysfunction were employed. The scopolamine model was the most used (n = 21); the other studies induced cognitive dysfunction by means of benzodiazepines (8), hypoxia (7), alcohol (5) and sleep-deprivation (4). The remaining 16 multiple-dose studies were clinical trials of a duration varying between 2 weeks and 1 year (average duration was 14 weeks). In these trials, the effects of cognition enhancers were assessed in elderly people in whom impairment of memory, psychomotor performance or cognitive function was determined. These included age-associated memory impairment (AAMI) and age-associated cognitive decline (AACD). There were many studies in which the cognition enhancing properties of substances in humans were reliably demonstrated. The cognition enhancing properties of substances that are widely used, such as caffeine, nicotine and vitamins, may already be active against AACD. New

  12. Clinically important FEV1 declines among coal miners: an exploration of previously unrecognised determinants

    PubMed Central

    Wang, M. L.; Petsonk, E. L.; Beeckman, L. A.; Wagner, G. R.

    1999-01-01

    OBJECTIVES: The relation between occupational exposure to dust and loss of ventilatory lung function is now well established. However, many exposures during work and other activities might also have important roles in determining clinically important losses of lung function. In this study, we attempted to explore additional plausible determinants of exposures and other potential risk factors for clinically important decline in forced expiratory volume in 1 second (FEV1) during work in dusty trades. METHODS: The study was performed in 264 underground coal miners whose lung function had been followed up for an average of 11 years. With an extensive follow up questionnaire, miners were asked about their occupational and non-occupational exposures, smoking, personal and family medical history, and living conditions during childhood. RESULTS: Several variables of the mine environment (as well as previously recognised effects of mining work and region) were found to be associated with excess decline in FEV1, including work in roof bolting, exposure to explosive blasting, and to control dust spraying water that had been stored in holding tanks. Use of respiratory protection seemed to reduce the risk of decline in FEV1. Other factors that were found to be associated with declines in pulmonary function included smoking, body mass, weight gain, childhood pneumonia, and childhood exposure in the home to passive tobacco smoke and possibly smoke due to wood and coal fuels. Miners with excessive decline in FEV1 were less likely to be working in mining jobs at follow up. CONCLUSIONS: These findings suggest the existence of additional risk factors for decline in lung function in dusty trades, and may be useful in developing additional approaches to the prevention of chronic respiratory disease.   PMID:10658541

  13. Clinical workout for the early detection of cognitive decline and dementia.

    PubMed

    Tsolaki, M

    2014-11-01

    Aging is the major risk factor for the development of human neurodegenerative maladies such as Alzheimer's, Huntington's and Parkinson's diseases (PDs) and prion disorders, all of which stem from toxic protein aggregation. All of these diseases are correlated with cognitive decline. Cognitive Decline is a dynamic state from normal cognition of aging to dementia. According to the original criteria for Alzheimer's Disease (AD) (1984), a clinical diagnosis was possible only when someone was already demented. The prevalence rates of Cognitive Decline (mild cognitive impairment plus dementia) are very high now and will be higher in future because of the increasing survival time of people. Many neurological and psychiatric diseases are correlated with cognitive decline. Diagnosis of cognitive decline is mostly clinical (clinical criteria), but there are multiple biomarkers that could help us mostly in research programs such as short or long, paper and pencil or computerized neuropsychological batteries for cognition, activities of daily living and behavior, electroencephalograph, event-related potentials, and imaging-structural magnetic resonance imaging (MRI) and functional (fMRI, Pittsburgh bound positron emission tomography, FDG-PET, single photon emission computerized tomography and imaging of tau pathology)-cerebrospinal fluid proteins (Abeta, tau and phospho-tau in AD and α-synuclein (αSyn) for PD). Blood biomarkers need more studies to confirm their usefulness. Genetic markers are also studied but until now are not used in clinical praxis. Finally, in everyday clinical praxis and in research workout for early detection of cognitive decline, the combination of biomarkers is useful.

  14. Terminal Decline in Well-Being: The Role of Social Orientation

    PubMed Central

    Gerstorf, Denis; Hoppmann, Christiane A.; Löckenhoff, Corinna E.; Infurna, Frank J.; Schupp, Jürgen; Wagner, Gert G.; Ram, Nilam

    2016-01-01

    Well-being development at the end of life is often characterized by steep deteriorations, but individual differences in these terminal declines are substantial and not yet well understood. This study moved beyond the typical consideration of health predictors and explored the role of social orientation and engagement. To do so, we made use of social variables at the behavioral level (self-ratings of social participation) and the motivational level (valuing social and family goals), assessed two to four years before death. We applied single- and multi-phase growth models to up to 27-year annual longitudinal data from 2,910 now deceased participants of the nation-wide German Socio-Economic Panel Study (SOEP; age at death: M = 74 years; SD = 14; 48% women). Results revealed that leading a socially active life and prioritizing social goals in late life were independently associated with higher late-life well-being, less pronounced late-life decline, and a later onset of terminal decline. Significant interaction effects suggested that the effects of (reduced) social participation and (lowered) social goals were compounding each other.compound. Findings also indicated that less decline in social participation was associated with shallower rates and a later onset of well-being decline. We found little evidence that valuing family goals is associated with late-life trajectories of well-being. Associations were independent of key correlates of well-being and mortality, including age at death, gender, education, disability, hospital stays, and goals in other life domains. We discuss possible pathways by which maintaining social orientation into late life may help mitigate terminal decline in well-being. PMID:26950226

  15. Effects of whole-body vibration applied to lower extremity muscles during decline bench press exercise

    PubMed Central

    García-Gutiérrez, M.T.; Hazell, T.J.; Marín, P.J.

    2016-01-01

    Objectives: To evaluate the effects of whole-body vibration (WBV) on skeletal muscle activity and power performance of the upper body during decline bench press exercise at different loads. Methods: Forty-seven healthy young and active male students volunteered. Each performed dynamic decline bench press repetitions with and without WBV (50 Hz, 2.2 mm) applied through a hamstring bridge exercise at three different loads of their 1-repetition maximum (1RM): 30%, 50%, and 70% 1RM. Muscle activity of the triceps brachii (TB), biceps brachii (BB), pectoralis major (PM), and biceps femoris (BF) was measured with surface electromyography electrodes and kinetic parameters of the repetitions were measured with a rotary encoder. Results: WBV increased peak power (PP) output during the 70% 1RM condition (p<0.01). Muscle activity was increased with WBV in the TB and BF muscles at all loads (p<0.05). There were no effects of WBV on BB or PM muscles. Conclusion: WBV applied through a hamstring bridge exercise increases TB muscle activity during a decline bench press and this augmentation contributes to an increased peak power at higher loads and increased peak acceleration at lower loads. PMID:27609035

  16. A Decline in Numeracy Skills among Bioscience Undergraduates.

    ERIC Educational Resources Information Center

    Tariq, Vicki N.

    2002-01-01

    Provides evidence of a decline in basic numeracy skills among first-year bioscience undergraduate students. Tests conceptualized numeracy skills which form a component of an introductory microbiology module. (Contains 23 references.) (Author/YDS)

  17. The Box Turtle: Room with a View on Species Decline.

    ERIC Educational Resources Information Center

    Belzer, Bill; Steisslinger, Mary Beth

    1999-01-01

    Surveys salient aspects of eastern box-turtle natural history. Explores the societal and ecological factors that have contributed to the decline of the box-turtle population. Contains 18 references. (WRM)

  18. DUI Rates Decline for U.S. Drivers

    MedlinePlus

    ... fullstory_162819.html DUI Rates Decline for U.S. Drivers But that doesn't mean roads will be ... 15 percent for 2002. Despite this decrease, however, drivers and their passengers remain at risk. An estimated ...

  19. When can the cause of a population decline be determined?

    USGS Publications Warehouse

    Hefley, Trevor J.; Hooten, Mevin B.; Drake, John M.; Russell, Robin E.; Walsh, Daniel P.

    2016-01-01

    Inferring the factors responsible for declines in abundance is a prerequisite to preventing the extinction of wild populations. Many of the policies and programmes intended to prevent extinctions operate on the assumption that the factors driving the decline of a population can be determined. Exogenous factors that cause declines in abundance can be statistically confounded with endogenous factors such as density dependence. To demonstrate the potential for confounding, we used an experiment where replicated populations were driven to extinction by gradually manipulating habitat quality. In many of the replicated populations, habitat quality and density dependence were confounded, which obscured causal inference. Our results show that confounding is likely to occur when the exogenous factors that are driving the decline change gradually over time. Our study has direct implications for wild populations, because many factors that could drive a population to extinction change gradually through time.

  20. ALIEN SPECIES: THEIR ROLE IN AMPHIBIAN POPULATION DECLINES AND RESTORATION

    EPA Science Inventory

    Alien species (also referred to as exotic, invasive, introduced, or normative species) have been implicated as causal agents in population declines of many amphibian species. Herein, we evaluate the relative contributions of alien species and other factors in adversely affecting ...

  1. Where Medical Pot Is Legal, Fatal Car Crashes Often Decline

    MedlinePlus

    ... 162675.html Where Medical Pot Is Legal, Fatal Car Crashes Often Decline It's possible that these state ... and Human Services. More Health News on: Marijuana Motor Vehicle Safety Recent Health News Related MedlinePlus Health ...

  2. Neuropsychological tests for predicting cognitive decline in older adults

    PubMed Central

    Baerresen, Kimberly M; Miller, Karen J; Hanson, Eric R; Miller, Justin S; Dye, Richelin V; Hartman, Richard E; Vermeersch, David; Small, Gary W

    2015-01-01

    Summary Aim To determine neuropsychological tests likely to predict cognitive decline. Methods A sample of nonconverters (n = 106) was compared with those who declined in cognitive status (n = 24). Significant univariate logistic regression prediction models were used to create multivariate logistic regression models to predict decline based on initial neuropsychological testing. Results Rey–Osterrieth Complex Figure Test (RCFT) Retention predicted conversion to mild cognitive impairment (MCI) while baseline Buschke Delay predicted conversion to Alzheimer’s disease (AD). Due to group sample size differences, additional analyses were conducted using a subsample of demographically matched nonconverters. Analyses indicated RCFT Retention predicted conversion to MCI and AD, and Buschke Delay predicted conversion to AD. Conclusion Results suggest RCFT Retention and Buschke Delay may be useful in predicting cognitive decline. PMID:26107318

  3. Folic Acid Supplements: Can They Slow Cognitive Decline?

    MedlinePlus

    ... slow cognitive decline? I've heard that folic acid supplements can improve cognitive function in older adults. ... those with Alzheimer's disease also benefit from folic acid? Answers from Paul Y. Takahashi, M.D. There's ...

  4. Recent advances in explaining fertility declines in the third world.

    PubMed

    Sharma, R K

    1984-01-01

    The purpose of this discussion is to provide a theoretical-methodological review of some recent socioeconomic theories that have been advanced to explain fertility decline in the 3rd world. Each theory is analyzed in terms of its theoretical claims and the methodology used in testing it. The intent is not so much with whether a particular theory has succeeded in explaining fertility decline but rather with the theoretical-methodological problems inherent in any attempt to explain fertility decline. The theories chosen are those theories that are explicity sociological in orientation or those that contain a significant sociological component. These theories are classified into 4 groups: proximate determinants of fertility; the "Synthesis Framework" of Easterlin; styles of development and fertility decline; and the "Wealth Flow" theory of fertility decline. Bongaarts (1978) developed an analytically simple yet comprehensive quantitative model of the relationship between the so-called intermediate variables and fertility. It can be either biological (such as sterility) or behavioral (such as contraceptive use)in nature. The most important finding from the application of Bongaart¿s framework (1982) is that fertility differences among populations are primarily due to variations in only 4 intermediate variables, namely proportion married, contraception, induced abortion, and postpartum infecundability. A knowledge of which proximate variable is responsible for fertility decline can narrow the search for social causes. The task of social research isultimately to understand such social causes that work through proximate variables to determine fertility. The "Synthesis Framework" of Easterlin attempts to accomplish precisely this by incorporating proximate variables within a broader socioeconomic framework. Those attempting to study the relationship between styles of development and fertility decline share this objective. The task of fertility research needs to be expanded

  5. White Matter Integrity Declined Over 6-Months, but Dance Intervention Improved Integrity of the Fornix of Older Adults.

    PubMed

    Burzynska, Agnieszka Z; Jiao, Yuqin; Knecht, Anya M; Fanning, Jason; Awick, Elizabeth A; Chen, Tammy; Gothe, Neha; Voss, Michelle W; McAuley, Edward; Kramer, Arthur F

    2017-01-01

    Degeneration of cerebral white matter (WM), or structural disconnection, is one of the major neural mechanisms driving age-related decline in cognitive functions, such as processing speed. Past cross-sectional studies have demonstrated beneficial effects of greater cardiorespiratory fitness, physical activity, cognitive training, social engagement, and nutrition on cognitive functioning and brain health in aging. Here, we collected diffusion magnetic resonance (MRI) imaging data from 174 older (age 60-79) adults to study the effects of 6-months lifestyle interventions on WM integrity. Healthy but low-active participants were randomized into Dance, Walking, Walking + Nutrition, and Active Control (stretching and toning) intervention groups (NCT01472744 on ClinicalTrials.gov). Only in the fornix there was a time × intervention group interaction of change in WM integrity: integrity declined over 6 months in all groups but increased in the Dance group. Integrity in the fornix at baseline was associated with better processing speed, however, change in fornix integrity did not correlate with change in processing speed. Next, we observed a decline in WM integrity across the majority of brain regions in all participants, regardless of the intervention group. This suggests that the aging of the brain is detectable on the scale of 6-months, which highlights the urgency of finding effective interventions to slow down this process. Magnitude of WM decline increased with age and decline in prefrontal WM was of lesser magnitude in older adults spending less time sedentary and more engaging in moderate-to-vigorous physical activity. In addition, our findings support the anterior-to-posterior gradient of greater-to-lesser decline, but only in the in the corpus callosum. Together, our findings suggest that combining physical, cognitive, and social engagement (dance) may help maintain or improve WM health and more physically active lifestyle is associated with slower WM decline

  6. White Matter Integrity Declined Over 6-Months, but Dance Intervention Improved Integrity of the Fornix of Older Adults

    PubMed Central

    Burzynska, Agnieszka Z.; Jiao, Yuqin; Knecht, Anya M.; Fanning, Jason; Awick, Elizabeth A.; Chen, Tammy; Gothe, Neha; Voss, Michelle W.; McAuley, Edward; Kramer, Arthur F.

    2017-01-01

    Degeneration of cerebral white matter (WM), or structural disconnection, is one of the major neural mechanisms driving age-related decline in cognitive functions, such as processing speed. Past cross-sectional studies have demonstrated beneficial effects of greater cardiorespiratory fitness, physical activity, cognitive training, social engagement, and nutrition on cognitive functioning and brain health in aging. Here, we collected diffusion magnetic resonance (MRI) imaging data from 174 older (age 60–79) adults to study the effects of 6-months lifestyle interventions on WM integrity. Healthy but low-active participants were randomized into Dance, Walking, Walking + Nutrition, and Active Control (stretching and toning) intervention groups (NCT01472744 on ClinicalTrials.gov). Only in the fornix there was a time × intervention group interaction of change in WM integrity: integrity declined over 6 months in all groups but increased in the Dance group. Integrity in the fornix at baseline was associated with better processing speed, however, change in fornix integrity did not correlate with change in processing speed. Next, we observed a decline in WM integrity across the majority of brain regions in all participants, regardless of the intervention group. This suggests that the aging of the brain is detectable on the scale of 6-months, which highlights the urgency of finding effective interventions to slow down this process. Magnitude of WM decline increased with age and decline in prefrontal WM was of lesser magnitude in older adults spending less time sedentary and more engaging in moderate-to-vigorous physical activity. In addition, our findings support the anterior-to-posterior gradient of greater-to-lesser decline, but only in the in the corpus callosum. Together, our findings suggest that combining physical, cognitive, and social engagement (dance) may help maintain or improve WM health and more physically active lifestyle is associated with slower WM decline

  7. Implications of Germany’s Declining Defense Spending

    DTIC Science & Technology

    2000-06-01

    security policy, defense spending is an important indicator. This thesis demonstrates that Germany’s defense expenditure seems to be inconsistent with its...Germany’s declining defense spending , it examines the reasons for and effects of Germany’s shrinking defense budget and suggests solutions for coping...Germany does not reverse the trend of declining defense spending it will probably decrease its political significance in Europe and in the world.

  8. The cause of global amphibian declines: a developmental endocrinologist's perspective

    PubMed Central

    Hayes, T. B.; Falso, P.; Gallipeau, S.; Stice, M.

    2010-01-01

    Greater than 70% of the world's amphibian species are in decline. We propose that there is probably not a single cause for global amphibian declines and present a three-tiered hierarchical approach that addresses interactions among and between ultimate and proximate factors that contribute to amphibian declines. There are two immediate (proximate) causes of amphibian declines: death and decreased recruitment (reproductive failure). Although much attention has focused on death, few studies have addressed factors that contribute to declines as a result of failed recruitment. Further, a great deal of attention has focused on the role of pathogens in inducing diseases that cause death, but we suggest that pathogen success is profoundly affected by four other ultimate factors: atmospheric change, environmental pollutants, habitat modification and invasive species. Environmental pollutants arise as likely important factors in amphibian declines because they have realized potential to affect recruitment. Further, many studies have documented immunosuppressive effects of pesticides, suggesting a role for environmental contaminants in increased pathogen virulence and disease rates. Increased attention to recruitment and ultimate factors that interact with pathogens is important in addressing this global crisis. PMID:20190117

  9. A re-examination of the projected subtropical precipitation decline

    NASA Astrophysics Data System (ADS)

    He, Jie; Soden, Brian J.

    2017-01-01

    A large-scale precipitation decline in the subtropics is a widely accepted projection of future climate change, but its causes and implications are uncertain. Two mechanisms are commonly used to explain the large-scale subtropical precipitation decline: an amplification of moisture export due to the increase in moisture and a poleward shift of subtropical subsidence associated with the poleward expansion of the Hadley cell. In an idealized experiment with abrupt CO2 increase, we find that the subtropical precipitation decline forms primarily in the fast adjustment to CO2 forcing during which neither of the two proposed mechanisms exists. Permitting the increase in moisture and the Hadley cell expansion does not substantially change the characteristics of the large-scale subtropical precipitation decline. This precipitation change should be interpreted as a response to the land-sea warming contrast, the direct radiative forcing of CO2 and, in certain regions, the pattern of SST changes. Moreover, the subtropical precipitation decline is projected predominately over oceans. Over subtropical land regions, the precipitation decline is muted or even reversed by the land-sea warming contrast.

  10. Interpreting Gas Production Decline Curves By Combining Geometry and Topology

    NASA Astrophysics Data System (ADS)

    Ewing, R. P.; Hu, Q.

    2014-12-01

    Shale gas production forms an increasing fraction of domestic US energy supplies, but individual gas production wells show steep production declines. Better understanding of this production decline would allow better economic forecasting; better understanding of the reasons behind the decline would allow better production management. Yet despite these incentives, production declines curves remain poorly understood, and current analyses range from Arps' purely empirical equation to new sophisticated approaches requiring multiple unavailable parameters. Models often fail to capture salient features: for example, in log-log space many wells decline with an exponent markedly different from the -0.5 expected from diffusion, and often show a transition from one decline mode to another. We propose a new approach based on the assumption that the rate-limiting step is gas movement from the matrix to the induced fracture network. The matrix is represented as an assemblage of equivalent spheres (geometry), with low matrix pore connectivity (topology) that results in a distance-dependent accessible porosity profile given by percolation theory. The basic theory has just 2 parameters: the sphere size distribution (geometry), and the crossover distance (topology) that characterizes the porosity distribution. The theory is readily extended to include e.g. alternative geometries and bi-modal size distributions. Comparisons with historical data are promising.

  11. Responses of riparian cottonwoods to alluvial water table declines

    USGS Publications Warehouse

    Scott, M.L.; Shafroth, P.B.; Auble, G.T.

    1999-01-01

    Human demands for surface and shallow alluvial groundwater have contributed to the loss, fragmentation, and simplification of riparian ecosystems. Populus species typically dominate riparian ecosystems throughout arid and semiarid regions of North American and efforts to minimize loss of riparian Populus requires an integrated understanding of the role of surface and groundwater dynamics in the establishment of new, and maintenance of existing, stands. In a controlled, whole-stand field experiment, we quantified responses of Populus morphology, growth, and mortality to water stress resulting from sustained water table decline following in-channel sand mining along an ephemeral sandbed stream in eastern Colorado, USA. We measured live crown volume, radial stem growth, annual branch increment, and mortality of 689 live Populus deltoides subsp. monilifera stems over four years in conjunction with localized water table declines. Measurements began one year prior to mining and included trees in both affected and unaffected areas. Populus demonstrated a threshold response to water table declines in medium alluvial sands; sustained declines ???1 m produced leaf desiccation and branch dieback within three weeks and significant declines in live crown volume, stem growth, and 88% mortality over a three-year period. Declines in live Crown volume proved to be a significant leading indicator of mortality in the following year. A logistic regression of tree survival probability against the prior year's live crown volume was significant (-2 log likelihood = 270, ??2 with 1 df = 232, P < 0.0001) and trees with absolute declines in live crown volume of ???30 during one year had survival probabilities <0.5 in the following year. In contrast, more gradual water table declines of ~0.5 m had no measurable effect on mortality, stem growth, or live crown volume and produced significant declines only in annual branch growth increments. Developing quantitative information on the timing and

  12. Declines in late-life disability: the role of early- and mid-life factors

    PubMed Central

    Freedman, Vicki A.; Martin, Linda G; Schoeni, Robert F; Cornman, Jennifer C

    2008-01-01

    Investigations into the causes of declines in late-life disability have largely focused on the role of contemporaneous factors. Adopting a life-course perspective as a backdrop, in this paper we ask whether there also has been a role for selected early- and mid-life factors in the decline, and if so whether these factors have been operating through changes in the risks of disability onset or recovery. Drawing on five waves from 1995 to 2004 of the US Health and Retirement Study, we found for the 75 and older population in the United States that the prevalence of difficulty with activities of daily living (ADL) declined from 30.2% in 1995 to 26.0% in 2004, whereas the trend in difficulty with instrumental activities of daily living (IADL) was flat. Onset of ADL limitations also was reduced during this period while recovery increased. Changes in the educational composition of the older population were linked to declines in the prevalence of ADL limitations, but there were also modest contributions of changes in mother's education, self-rated childhood health, and lifetime occupation. Declines in late-life vision impairments and increases in wealth also contributed substantially to the downward trend, and had chronic conditions not increased, it would have been even larger. Reductions in the onset of ADL limitations were partly driven by changes in educational attainment of respondents and their mothers and, in late-life, better vision and wealth. In contrast, the recovery trend was not accounted for by changes in early- or mid-life factors. We conclude that early- and mid-life factors have contributed along with late-life factors to U.S. late-life disability trends mainly through their influence on the onset of, rather than recovery from, limitations. PMID:18222580

  13. Increased neurocognitive intra-individual variability is associated with declines in medication adherence in HIV-infected adults

    PubMed Central

    Thaler, Nicholas S.; Sayegh, Philip; Arentoft, Alyssa; Thames, April D.; Castellon, Steven A.; Hinkin, Charlie H.

    2015-01-01

    There is cross-sectional evidence that neurocognitive intra-individual variability (IIV), or dispersion, is elevated in HIV disease and is associated with declines in activities of daily living, including medication adherence. This longitudinal study extends this literature by examining whether increased neurocognitive IIV in HIV+ persons over time predicts declines in medication adherence above and beyond changes in mean level of performance over a six-month observation. After controlling for drug use, declines in mean performance, and changes in depressive symptoms, results confirmed that increases in IIV were associated with overall poorer antiretroviral medication adherence. HIV+ individuals with the greatest increases in dispersion demonstrated marked reductions in adherence by the third month that exceed that observed in less variable individuals. Our results indicate that increases in dispersion are associated with poorer declines in medication adherence in HIV disease, which may have implications for the early detection and remediation of suboptimal antiretroviral adherence. PMID:25730729

  14. Seasonal change in tropical habitat quality and body condition for a declining migratory songbird.

    PubMed

    McKinnon, Emily A; Rotenberg, James A; Stutchbury, Bridget J M

    2015-10-01

    Many migratory songbirds spend their non-breeding season in tropical humid forests, where climate change is predicted to increase the severity and frequency of droughts and decrease rainfall. For conservation of these songbirds, it is critical to understand how resources during the non-breeding season are affected by seasonal patterns of drying, and thereby predict potential long-term effects of climate change. We studied habitat quality for a declining tropical forest-dwelling songbird, the wood thrush (Hylocichla mustelina), and tested the hypothesis that habitat moisture and arthropod abundance are drivers of body condition during the overwintering period. We examined habitat moisture, abundance of arthropods and fruit, and condition of individual birds (n = 418) in three habitat types--mature forest, mature forest with increased presence of human activity, and riparian scrub--from October to April. We found a strong pattern of habitat drying from October (wet season) to March (prior to spring migration) in all habitats, with concurrent declines in arthropod and fruit abundance. Body condition of birds also declined (estimated ~5 % decline over the wintering period), with no significant difference by habitat. Relatively poor condition (low body condition index, low fat and pectoral muscles scores) was equally apparent in all habitat types in March. Climate change is predicted to increase the severity of dry seasons in Central America, and our results suggest that this could negatively affect the condition of individual wood thrushes.

  15. Decline of Yangtze River water and sediment discharge: Impact from natural and anthropogenic changes

    PubMed Central

    Yang, S. L.; Xu, K. H.; Milliman, J. D.; Yang, H. F.; Wu, C. S.

    2015-01-01

    The increasing impact of both climatic change and human activities on global river systems necessitates an increasing need to identify and quantify the various drivers and their impacts on fluvial water and sediment discharge. Here we show that mean Yangtze River water discharge of the first decade after the closing of the Three Gorges Dam (TGD) (2003–2012) was 67 km3/yr (7%) lower than that of the previous 50 years (1950–2002), and 126 km3/yr less compared to the relatively wet period of pre-TGD decade (1993–2002). Most (60–70%) of the decline can be attributed to decreased precipitation, the remainder resulting from construction of reservoirs, improved water-soil conservation and increased water consumption. Mean sediment flux decreased by 71% between 1950–1968 and the post-TGD decade, about half of which occurred prior to the pre-TGD decade. Approximately 30% of the total decline and 65% of the decline since 2003 can be attributed to the TGD, 5% and 14% of these declines to precipitation change, and the remaining to other dams and soil conservation within the drainage basin. These findings highlight the degree to which changes in riverine water and sediment discharge can be related with multiple environmental and anthropogenic factors. PMID:26206169

  16. Diclofenac residues as the cause of vulture population decline in Pakistan.

    PubMed

    Oaks, J Lindsay; Gilbert, Martin; Virani, Munir Z; Watson, Richard T; Meteyer, Carol U; Rideout, Bruce A; Shivaprasad, H L; Ahmed, Shakeel; Chaudhry, Muhammad Jamshed Iqbal; Arshad, Muhammad; Mahmood, Shahid; Ali, Ahmad; Khan, Aleem Ahmed

    2004-02-12

    The Oriental white-backed vulture (OWBV; Gyps bengalensis) was once one of the most common raptors in the Indian subcontinent. A population decline of >95%, starting in the 1990s, was first noted at Keoladeo National Park, India. Since then, catastrophic declines, also involving Gyps indicus and Gyps tenuirostris, have continued to be reported across the subcontinent. Consequently these vultures are now listed as critically endangered by BirdLife International. In 2000, the Peregrine Fund initiated its Asian Vulture Crisis Project with the Ornithological Society of Pakistan, establishing study sites at 16 OWBV colonies in the Kasur, Khanewal and Muzaffargarh-Layyah Districts of Pakistan to measure mortality at over 2,400 active nest sites. Between 2000 and 2003, high annual adult and subadult mortality (5-86%) and resulting population declines (34-95%) (ref. 5 and M.G., manuscript in preparation) were associated with renal failure and visceral gout. Here, we provide results that directly correlate residues of the anti-inflammatory drug diclofenac with renal failure. Diclofenac residues and renal disease were reproduced experimentally in OWBVs by direct oral exposure and through feeding vultures diclofenac-treated livestock. We propose that residues of veterinary diclofenac are responsible for the OWBV decline.

  17. Diclofenac residues as the cause of vulture population decline in Pakistan

    USGS Publications Warehouse

    Oaks, J.L.; Gilbert, M.; Virani, M.Z.; Watson, R.T.; Meteyer, C.U.; Rideout, B.A.; Shivaprasad, H.L.; Ahmed, S.; Chaudhry, M.J.I.; Arshad, M.; Mahmood, S.; Ali, A.; Khan, A.A.

    2004-01-01

    The Oriental white-backed vulture (OWBV; Gyps bengalensis) was once one of the most common raptors in the Indian subcontinent. A population decline of >95%, starting in the 1990s, was first noted at Keoladeo National Park, India. Since then, catastrophic declines, also involving Gyps indicus and Gyps tenuirostris, have continued to be reported across the subcontinent. Consequently these vultures are now listed as critically endangered by BirdLife International. In 2000, the Peregrine Fund initiated its Asian Vulture Crisis Project with the Ornithological Society of Pakistan, establishing study sites at 16 OWBV colonies in the Kasur, Khanewal and Muzaffargarha??Layyah Districts of Pakistan to measure mortality at over 2,400 active nest sites5. Between 2000 and 2003, high annual adult and subadult mortality (5a??86%) and resulting population declines (34a??95%) (ref. 5 and M.G., manuscript in preparation) were associated with renal failure and visceral gout. Here, we provide results that directly correlate residues of the anti-inflammatory drug diclofenac with renal failure. Diclofenac residues and renal disease were reproduced experimentally in OWBVs by direct oral exposure and through feeding vultures diclofenac-treated livestock. We propose that residues of veterinary diclofenac are responsible for the OWBV decline.

  18. Passive acoustic monitoring of the decline of Mexico's critically endangered vaquita.

    PubMed

    Jaramillo-Legorreta, Armando; Cardenas-Hinojosa, Gustavo; Nieto-Garcia, Edwyna; Rojas-Bracho, Lorenzo; Ver Hoef, Jay; Moore, Jeffrey; Tregenza, Nicholas; Barlow, Jay; Gerrodette, Tim; Thomas, Len; Taylor, Barbara

    2017-02-01

    The vaquita (Phocoena sinus) is the world's most endangered marine mammal with approximately 245 individuals remaining in 2008. This species of porpoise is endemic to the northern Gulf of California, Mexico, and historically the population has declined because of unsustainable bycatch in gillnets. An illegal gillnet fishery for an endangered fish, the totoaba (Totoaba macdonaldi), has recently resurged throughout the vaquita's range. The secretive but lucrative wildlife trade with China for totoaba swim bladders has probably increased vaquita bycatch mortality by an unknown amount. Precise population monitoring by visual surveys is difficult because vaquitas are inherently hard to see and have now become so rare that sighting rates are very low. However, their echolocation clicks can be identified readily on specialized acoustic detectors. Acoustic detections on an array of 46 moored detectors indicated vaquita acoustic activity declined by 80% between 2011 and 2015 in the central part of the species' range. Statistical models estimated an annual rate of decline of 34% (95% Bayesian credible interval -48% to -21%). Based on results from 2011 to 2014, the government of Mexico enacted and is enforcing an emergency 2-year ban on gillnets throughout the species' range to prevent extinction, at a cost of US$74 million to compensate fishers. Developing precise acoustic monitoring methods proved critical to exposing the severity of vaquitas' decline and emphasizes the need for continual monitoring to effectively manage critically endangered species.

  19. Prevention of Age-Related Cognitive Decline: Which Strategies, When, and for Whom?

    PubMed

    Shatenstein, Bryna; Barberger-Gateau, Pascale; Mecocci, Patrizia

    2015-01-01

    Brain aging is characterized by the progressive and gradual accumulation of detrimental changes in structure and function, which increase risk of age-related cognitive decline and dementia. This devastating chronic condition generates a huge social and economic burden and accounts for 11.2% of years of disability. The increase in lifespan has contributed to the increase in dementia prevalence; however, there is currently no curative treatment for most causes of dementias. This paper reviews evidence-based strategies to build, enhance, and preserve cognition over the lifespan by examining approaches that work best, proposing when in the life course they should be implemented, and in which population group(s). Recent work shows a tendency to decreased age-specific prevalence and incidence of cognitive problems and dementia among people born later in the first half of the 20th century, citing higher educational levels, improvements in lifestyle, and better handling of vascular risk factors. This implies that we can target modifiable environmental, lifestyle, and health risk factors to modify the trajectory of cognitive decline before the onset of irreversible dementia. Because building cognitive reserve and prevention of cognitive decline are of critical importance, interventions are needed at every stage of the life course to foster cognitive stimulation, and enable healthy eating habits and physical activity throughout the lifespan. Preventive interventions to decrease and delay cognitive decline and its consequences in old age will also require collaboration and action on the part of policy-makers at the political and social level.

  20. Hot Topics in Research: Preventive Neuroradiology in Brain Aging and Cognitive Decline.

    PubMed

    Raji, C A; Eyre, H; Wei, S H; Bredesen, D E; Moylan, S; Law, M; Small, G; Thompson, P M; Friedlander, R M; Silverman, D H; Baune, B T; Hoang, T A; Salamon, N; Toga, A W; Vernooij, M W

    2015-10-01

    Preventive neuroradiology is a new concept supported by growing literature. The main rationale of preventive neuroradiology is the application of multimodal brain imaging toward early and subclinical detection of brain disease and subsequent preventive actions through identification of modifiable risk factors. An insightful example of this is in the area of age-related cognitive decline, mild cognitive impairment, and dementia with potentially modifiable risk factors such as obesity, diet, sleep, hypertension, diabetes, depression, supplementation, smoking, and physical activity. In studying this link between lifestyle and cognitive decline, brain imaging markers may be instrumental as quantitative measures or even indicators of early disease. The purpose of this article is to provide an overview of the major studies reflecting how lifestyle factors affect the brain and cognition aging. In this hot topics review, we will specifically focus on obesity and physical activity.

  1. Rapid declines in metabolism explain extended coral larval longevity

    NASA Astrophysics Data System (ADS)

    Graham, E. M.; Baird, A. H.; Connolly, S. R.; Sewell, M. A.; Willis, B. L.

    2013-06-01

    Lecithotrophic, or non-feeding, marine invertebrate larvae generally have shorter pelagic larval durations (PLDs) than planktotrophic larvae. However, non-feeding larvae of scleractinian corals have PLDs far exceeding those of feeding larvae of other organisms and predictions of PLD based on energy reserves and metabolic rates, raising questions about how such longevity is achieved. Here, we measured temporal changes in metabolic rates and total lipid content of non-feeding larvae of four species of reef corals to determine whether changes in energy utilization through time contribute to extended larval durations. The temporal dynamics of both metabolic rates and lipid content were highly consistent among species. Prior to fertilization, metabolic rates were low (2.73-8.63 nmol O2 larva-1 h-1) before rapidly increasing to a peak during embryogenesis and early development 1-2 days after spawning. Metabolic rates remained high until shortly after larvae first became competent to metamorphose and then declined by up to two orders of magnitude to levels at or below rates seen in unfertilized eggs over the following week. Larvae remained in this state of low metabolic activity for up to 2 months. Consistent with temporal patterns in metabolic rates, depletion of lipids was extremely rapid during early development and then slowed dramatically from 1 week onward. Despite the very low metabolic rates in these species, larvae continued to swim and retained competence for at least 2 months. The capacity of non-feeding coral larvae to enter a state of low metabolism soon after becoming competent to metamorphose significantly extends dispersal potential, thereby accruing advantages typically associated with planktotrophy, notably enhanced population connectivity.

  2. Focus on Freshman: Basic Instruction Programs Enhancing Physical Activity

    ERIC Educational Resources Information Center

    Curry, Jarred; Jenkins, Jayne M.; Weatherford, Jennifer

    2015-01-01

    Physical activity sharply decreases after different life stages, particularly high school graduation to beginning university education. The purpose of this study was to investigate the effect of a specifically designed university physical activity class, Exercise Planning for Freshman (EPF), on students' physical activity and group cohesion…

  3. Season-controlled changes in biochemical constituents and oxidase enzyme activities in tomato (Lycopersicon esculentum Mill.).

    PubMed

    Sen, Supatra; Mukherji, S

    2009-07-01

    Season-controlled changes in biochemical constituents viz. carotenoids (carotene and xanthophyll) and pectic substances along with IAA-oxidase and polyphenol oxidase (PPO) enzyme activities were estimated/assayed in leaves of Lycopersicon esculentum Mill. (tomato) in two developmental stages--pre-flowering (35 days after sowing) and post-flowering (75 days after sowing) in three different seasons--summer rainy and winter Carotenoid content along with pectic substances were highest in winter and declined significantly in summer followed by rainy i.e. winter > summer > rainy. Carotenoid content was significantly higher in the pre-flowering as compared to post-flowering in all three seasons while pectic substances increased in the post-flowering as compared to pre-flowering throughout the annual cycle. IAA oxidase and PPO enzyme activities were enhanced in rainy and decreased sharply in summer and winter i.e. rainy > summer > winter. Both the enzymes exhibited higher activity in the post-flowering stage as compared to pre-flowering in all three seasons. These results indicate winter to be the most favourable season for tomato plants while rainy season environmental conditions prove to be unfavourable (stressful) with diminished content of carotenoid and pectic substances and low activities of IAA oxidase and PPO, ultimately leading to poor growth and productivity.

  4. Detecting insect pollinator declines on regional and global scales

    USGS Publications Warehouse

    Lubuhn, Gretchen; Droege, Sam; Connor, Edward F.; Gemmill-Herren, Barbara; Potts, Simon G.; Minckley, Robert L.; Griswold, Terry; Jean, Robert; Kula, Emanuel; Roubik, David W.; Cane, Jim; Wright, Karen W.; Frankie, Gordon; Parker, Frank

    2013-01-01

    Recently there has been considerable concern about declines in bee communities in agricultural and natural habitats. The value of pollination to agriculture, provided primarily by bees, is >$200 billion/year worldwide, and in natural ecosystems it is thought to be even greater. However, no monitoring program exists to accurately detect declines in abundance of insect pollinators; thus, it is difficult to quantify the status of bee communities or estimate the extent of declines. We used data from 11 multiyear studies of bee communities to devise a program to monitor pollinators at regional, national, or international scales. In these studies, 7 different methods for sampling bees were used and bees were sampled on 3 different continents. We estimated that a monitoring program with 200-250 sampling locations each sampled twice over 5 years would provide sufficient power to detect small (2-5%) annual declines in the number of species and in total abundance and would cost U.S.$2,000,000. To detect declines as small as 1% annually over the same period would require >300 sampling locations. Given the role of pollinators in food security and ecosystem function, we recommend establishment of integrated regional and international monitoring programs to detect changes in pollinator communities.

  5. Global amphibian declines: perspectives from the United States and beyond

    USGS Publications Warehouse

    Densmore, Christine L.; Cipriano, R.C.; Bruckner, A.W.; Shchelkunov, I.S.

    2011-01-01

    Over recent decades, amphibians have experienced population declines, extirpations and species-level extinctions at an alarming rate. Numerous potential etiologies for amphibian declines have been postulated including climate and habitat degradation. Other potential anthropogenic causes including overexploitation and the frequent introductions of invasive predatory species have also been blamed for amphibian declines. Still other underlying factors may include infectious diseases caused by the chytrid fungus Batrachochytrium dendrobatidis, pathogenic viruses (Ranavirus), and other agents. It is nearly certain that more than one etiology is to blame for the majority of the global amphibian declines, and that these causal factors include some combination of climatological or physical habitat destabilization and infectious disease, most notably chytridiomycosis. Scientific research efforts are aimed at elucidating these etiologies on local, regional, and global scales that we might better understand and counteract the driving forces behind amphibian declines. Conservation efforts as outlined in the Amphibian Conservation Action Plan of 2005 are also being made to curtail losses and prevent further extinctions wherever possible.

  6. Arctic Sea Ice Decline: Observations, Projections, Mechanisms, and Implications

    NASA Astrophysics Data System (ADS)

    DeWeaver, Eric T.; Bitz, Cecilia M.; Tremblay, L.-Bruno

    This volume addresses the rapid decline of Arctic sea ice, placing recent sea ice decline in the context of past observations, climate model simulations and projections, and simple models of the climate sensitivity of sea ice. Highlights of the work presented here include • An appraisal of the role played by wind forcing in driving the decline; • A reconstruction of Arctic sea ice conditions prior to human observations, based on proxy data from sediments; • A modeling approach for assessing the impact of sea ice decline on polar bears, used as input to the U.S. Fish and Wildlife Service's decision to list the polar bear as a threatened species under the Endangered Species Act; • Contrasting studies on the existence of a "tipping point," beyond which Arctic sea ice decline will become (or has already become) irreversible, including an examination of the role of the small ice cap instability in global warming simulations; • A significant summertime atmospheric response to sea ice reduction in an atmospheric general circulation model, suggesting a positive feedback and the potential for short-term climate prediction. The book will be of interest to researchers attempting to understand the recent behavior of Arctic sea ice, model projections of future sea ice loss, and the consequences of sea ice loss for the natural and human systems of the Arctic.

  7. Inquiry into terminal decline: five objectives for future study.

    PubMed

    Gerstorf, Denis; Ram, Nilam

    2013-10-01

    Notions of terminal decline propose that late-life change is primarily driven by processes closely tied to pathology and mortality rather than chronological age. We use the rationales of longitudinal research as outlined by Baltes and Nesselroade (Baltes, P., & Nesselroade, J. [1979]. History and rationale of longitudinal research. In J. R. Nesselroade & P. Baltes (Eds.), Longitudinal research in the study of behavior and development [pp. 1-39]. San Diego, CA: Academic Press) as a framework for organizing research on terminal decline. In doing so, we note that there are relatively robust descriptions of terminal decline across a variety of different domains, as well as the extent of interindividual differences in the levels of function, rates of change, and timing of terminal decline (research rationales 1 and 2). However, there is much more to learn about the interrelations among change in different domains, the underlying mechanisms of change, and the factors that contribute to interindividual differences in change (research rationales 3-5). Needed are new study designs and analytical models that better address the structural, temporal, and causal interrelations that contribute to and protect against terminal decline.

  8. Critical Decline of the Eastern Caribbean Sperm Whale Population

    PubMed Central

    Whitehead, Hal

    2016-01-01

    Sperm whale (Physeter macrocephalus) populations were expected to rebuild following the end of commercial whaling. We document the decline of the population in the eastern Caribbean by tracing demographic changes of well-studied social units. We address hypotheses that, over a ten-year period of dedicated effort (2005–2015), unit size, numbers of calves and/or calving rates have each declined. Across 16 units, the number of adults decreased in 12 units, increased in two, and showed no change in two. The number of adults per unit decreased at -0.195 individuals/yr (95% CI: -0.080 to -0.310; P = 0.001). The number of calves also declined, but the decline was not significant. This negative trend of -4.5% per year in unit size started in about 2010, with numbers being fairly stable until then. There are several natural and anthropogenic threats, but no well-substantiated cause for the decline. PMID:27706153

  9. Patterns of widespread decline in North American bumble bees

    PubMed Central

    Cameron, Sydney A.; Lozier, Jeffrey D.; Strange, James P.; Koch, Jonathan B.; Cordes, Nils; Solter, Leellen F.; Griswold, Terry L.

    2011-01-01

    Bumble bees (Bombus) are vitally important pollinators of wild plants and agricultural crops worldwide. Fragmentary observations, however, have suggested population declines in several North American species. Despite rising concern over these observations in the United States, highlighted in a recent National Academy of Sciences report, a national assessment of the geographic scope and possible causal factors of bumble bee decline is lacking. Here, we report results of a 3-y interdisciplinary study of changing distributions, population genetic structure, and levels of pathogen infection in bumble bee populations across the United States. We compare current and historical distributions of eight species, compiling a database of >73,000 museum records for comparison with data from intensive nationwide surveys of >16,000 specimens. We show that the relative abundances of four species have declined by up to 96% and that their surveyed geographic ranges have contracted by 23–87%, some within the last 20 y. We also show that declining populations have significantly higher infection levels of the microsporidian pathogen Nosema bombi and lower genetic diversity compared with co-occurring populations of the stable (nondeclining) species. Higher pathogen prevalence and reduced genetic diversity are, thus, realistic predictors of these alarming patterns of decline in North America, although cause and effect remain uncertain. PMID:21199943

  10. Decline in long-term growth trends of white oak

    USGS Publications Warehouse

    Phipps, R.L.; Whiton, J.C.

    1988-01-01

    Quercus alba tree-ring collections from 89 locations throughout much of its range, from Connecticut to North Carolina to Iowa, were examined for evidence of growth decline initiated in the 1950s. The expected trend of annual basal area increments, based on pre-1950 growth, appears to be linear, with the slope varying among collections relative to site quality. Growth decline, defined as departure of actual growth below that expected, was identified in 40 to 60 collections judged to have not been affected by local site histories. The percentage of collections showing decline was essentially the same in the Northeast, the Midwest and the Southeast. Onset of decline began during a relatively narrow time window from the mid-1950's to the early 1960's. Since then the growth trend has been linear and appears unrelated to changes in regional sulfur and nitrogen oxide emissions. Events or conditions, unique to the 1950's, initiated a growth rate change in c 2/3 of the stands examined. Initiation of the decline appears to be unrelated to tree age, geographic location, site quality, climatic trends, or regional emissions of sulfur and nitrogen oxides. -from Authors

  11. Sea otter population declines in the Aleutian Archipelago

    USGS Publications Warehouse

    Doroff, Angela; Estes, James A.; Tinker, M. Tim; Burn, Douglas M.; Evans, Thomas J.

    2003-01-01

    Sea otter (Enhydra lutris) populations were exploited to near extinction and began to recover after the cessation of commercial hunting in 1911. Remnant colonies of sea otters in the Aleutian archipelago were among the first to recover; they continued to increase through the 1980s but declined abruptly during the 1990s. We conducted an aerial survey of the Aleutian archipelago in 2000 and compared results with similar surveys conducted in 1965 and 1992. The number of sea otters counted decreased by 75% between 1965 and 2000; 88% for islands at equilibrial density in 1965. The population decline likely began in the mid-1980s and declined at a rate of 17.5%/year in the 1990s. The minimal population estimate was 8,742 sea otters in 2000. The population declined to a uniformly low density in the archipelago, suggesting a common and geographically widespread cause. These data are in general agreement with the hypothesis of increased predation on sea otters. These data chronicle one of the most widespread and precipitous population declines for a mammalian carnivore in recorded history.

  12. An Investigation of the Afternoon Decline in Tropical Forest Photosynthesis

    NASA Astrophysics Data System (ADS)

    Doughty, C.; Goulden, M. L.; Miller, S. D.; Menton, M. C.; da Rocha, H.; Freitas, H.; Figueira, M. A.; da Sousa, C. A.; Maia, A.

    2002-12-01

    The recent use of eddy covariance to measure the net exchange of CO2 between the atmosphere and a tropical forest in Santarem Para, Brazil, has indicated a substantial decline in forest photosynthesis in the afternoon, even after taking light differences into account. Afternoon declines in leaf-level gas exchange have been reported for many ecosystems, including tropical forests. Potential causes for this decline include stomatal responses to VPD, low leaf water potential, changes in biochemistry due to elevated temperature, photoinhibition, photorespiration, or intrinsic circadian rhythm. This study attempts to understand this decline by using leaf gas exchange to measure photosynthesis while canopy leaves are kept under constant light, humidity, and temperature conditions for 24 to 36 hours hours.At constant light levels of 100 PAR æmol~m-2s-1, 7 of 12 species tested showed a substantial decline photosynthesis at night, and a subsequent recovery in photosynthesis during the next day. In most cases, the internal CO2 of these plants increased at night, indicating that this diel cycle was not simply an effect of a circadian rhythm in stomatal conductance. Rather, the photosynthesis of a significant fraction of the plants surveyed appears to be under the direct control of a circadian oscillator.

  13. Forest declines: Some perspectives on linking processes and patterns

    SciTech Connect

    McLaughlin, S.B.

    1992-01-01

    The regional decline in vigor of some species of forest trees has become an important component in the ecological, aesthetic, and economic criteria by which the costs of anthropogenic pollution are weighed. Because declines are often complex and virtually never without significant natural environmental modifiers, determining the role of specific anthropogenic stresses in initiating or enhancing the rate and direction of change in forest condition represents a significant research challenge. Separation of primary mechanisms that point to principal causes from secondary responses that result from internal feedbacks and the milieu of modifying agents is a critical issue in diagnosing forest decline. Air pollutant stress may have its most significant effects on forest processes by accelerating or amplifying natural stresses. Studies of changes in forest metabolic processes have played an important role in evaluating the role of air pollution in four regional forest declines that are the focus of this paper. The decline of ponderosa pine in the San Bernardino Mountains of California, Norway spruce and silver fir in Europe, loblolly and shortleaf pine in the Southeastern United States, and red spruce in the Eastern Appalachian Mountains provide case studies in which physiological responses to air pollutants under field and laboratory conditions have provided important analytical tools for assessing likely causes. These tools are most effective when both mechanistic explanations and larger scale patterns of response are evaluated in an iterative feedback loop that examines plausible mechanisms and patterns of response at levels ranging from cell membranes to plant populations.

  14. Forest declines: Some perspectives on linking processes and patterns

    SciTech Connect

    McLaughlin, S.B.

    1992-09-01

    The regional decline in vigor of some species of forest trees has become an important component in the ecological, aesthetic, and economic criteria by which the costs of anthropogenic pollution are weighed. Because declines are often complex and virtually never without significant natural environmental modifiers, determining the role of specific anthropogenic stresses in initiating or enhancing the rate and direction of change in forest condition represents a significant research challenge. Separation of primary mechanisms that point to principal causes from secondary responses that result from internal feedbacks and the milieu of modifying agents is a critical issue in diagnosing forest decline. Air pollutant stress may have its most significant effects on forest processes by accelerating or amplifying natural stresses. Studies of changes in forest metabolic processes have played an important role in evaluating the role of air pollution in four regional forest declines that are the focus of this paper. The decline of ponderosa pine in the San Bernardino Mountains of California, Norway spruce and silver fir in Europe, loblolly and shortleaf pine in the Southeastern United States, and red spruce in the Eastern Appalachian Mountains provide case studies in which physiological responses to air pollutants under field and laboratory conditions have provided important analytical tools for assessing likely causes. These tools are most effective when both mechanistic explanations and larger scale patterns of response are evaluated in an iterative feedback loop that examines plausible mechanisms and patterns of response at levels ranging from cell membranes to plant populations.

  15. Perceived Personal Control Buffers Terminal Decline in Well-Being

    PubMed Central

    Gerstorf, Denis; Heckhausen, Jutta; Ram, Nilam; Infurna, Frank J.; Schupp, Juergen; Wagner, Gert G.

    2015-01-01

    Recent research has repeatedly demonstrated that well-being typically evinces precipitous deterioration close to the end of life. However, the determinants of individual differences in these terminal declines are note well understood. In this study, we examine the role of perceived personal control as a potential buffer against steep terminal declines in well-being. We applied single- and multi-phase growth models to up to 25-year longitudinal data from 1,641 now deceased participants of the national German Socio-Economic Panel Study (SOEP; age at death: M = 74 years; SD = 14; 49% women). Results revealed that perceiving more personal control over one’s life was related to subsequently higher late-life well-being, less severe rates of late-life declines, and a later onset of terminal decline. Associations were independent of key predictors of mortality, including age, gender, SES, and disability. These findings suggest that feeling in control may ameliorate steep end-of-life decline in well-being. We also discuss scenarios for when and how processes of goal disengagement and giving up control may become beneficial. PMID:25244480

  16. Patterns of widespread decline in North American bumble bees.

    PubMed

    Cameron, Sydney A; Lozier, Jeffrey D; Strange, James P; Koch, Jonathan B; Cordes, Nils; Solter, Leellen F; Griswold, Terry L

    2011-01-11

    Bumble bees (Bombus) are vitally important pollinators of wild plants and agricultural crops worldwide. Fragmentary observations, however, have suggested population declines in several North American species. Despite rising concern over these observations in the United States, highlighted in a recent National Academy of Sciences report, a national assessment of the geographic scope and possible causal factors of bumble bee decline is lacking. Here, we report results of a 3-y interdisciplinary study of changing distributions, population genetic structure, and levels of pathogen infection in bumble bee populations across the United States. We compare current and historical distributions of eight species, compiling a database of >73,000 museum records for comparison with data from intensive nationwide surveys of >16,000 specimens. We show that the relative abundances of four species have declined by up to 96% and that their surveyed geographic ranges have contracted by 23-87%, some within the last 20 y. We also show that declining populations have significantly higher infection levels of the microsporidian pathogen Nosema bombi and lower genetic diversity compared with co-occurring populations of the stable (nondeclining) species. Higher pathogen prevalence and reduced genetic diversity are, thus, realistic predictors of these alarming patterns of decline in North America, although cause and effect remain uncertain.

  17. State welfare reform policies and declines in health insurance.

    PubMed Central

    Chavkin, W; Romero, D; Wise, P H

    2000-01-01

    OBJECTIVES: This study sought to determine whether there is a relationship between state policies on Temporary Assistance to Needy Families (TANF), declines in both TANF and Medicaid caseloads, and the rise in the number of uninsured. METHODS: Extant data sources of state TANF policies, TANF and Medicaid participation, and uninsurance rates were analyzed, with the state as the unit of analysis. The independent variables included state TANF policies that directly address receipt of benefits or relate to health; dependent variables included changes in state TANF enrollment, Medicaid enrollment, and health insurance status since the enactment of the law. RESULTS: In the bivariate analysis, declines in Medicaid were associated with sanction for work noncompliance, lack of a child care guarantee, and strategies to deter TANF enrollment; this last factor was also associated with increased uninsurance. In the multivariate analysis, lack of a child care guarantee and deterrent strategies predicted TANF declines; deterrent strategies predicted Medicaid decline and uninsurance increases. CONCLUSIONS: This analysis suggests that policies deterring TANF enrollment may contribute to declines in Medicaid and increased uninsurance. To maintain health insurance for the poor, policymakers should consider revising policies that deter TANF enrollment. PMID:10846507

  18. [The decline in the population growth rate--a priority issue in international politics].

    PubMed

    Rhein, E

    1994-08-25

    The Third International UN Conference on Population and Development took place in Cairo in early September 1994 with the participation of 200 governments and 1000 nongovernmental organizations to discuss ways of stabilizing world population at the possible lowest level and how industrialized countries could contribute to this effort. As a consequence of the advances in reproductive medicine the use of contraceptives skyrocketed: in 1994 more than half of men and women were using contraception compared to only 5% in 1950. However, the demographic momentum would still increase world population for another 100 years, even if fertility would drop to 2.2 children per couple (compared to 4 children in 1990). Nevertheless, the present generation could be instrumental in deciding whether the world's population will remain around 8 billion or reach 12 billion between 2050 and 2150. Poor countries can no longer afford an annual growth rate of 2-4% while also trying to improve living standards; this would require an economic growth rate of 6-8%. For the control of population growth both a sustainable environmental policy in the North, with rapid transition to renewable energy and recycling, and a more effective population policy in the South are needed. Family planning (FP) is the precondition of stabilization. The global FP outlays are envisioned to double from the 1994 figure of $5 billion to over $10 billion in the year 2000, with donor contributions to increase from 20% to 40% of the total. The US contribution is to double from $500 million by 2000, while the European Commission decided to boost expenditures for FP from DM 30 million in 1994 to DM 600 million by 2000. Japan is also expending $3 billion during this period. Recent promising developments have emerged: national pronatalist policies have diminished sharply and the pronatalist influence of religions has also declined. Political commitment at the highest level is central to a successful population policy as

  19. Behavioral inhibition during a conflict state elicits a transient decline in hippocampal theta power.

    PubMed

    Sakimoto, Yuya; Sakata, Shogo

    2015-09-01

    Although it has been shown that hippocampal theta power transiently declines during response inhibition in a simultaneous feature negative (FN: A+, AB-) task, observations of additional changes after this initial decline have been inconsistent across subjects. We hypothesized that the cause of these inconsistencies might be that variations in the learning speed for the FN task differentially affect the changes in hippocampal theta activity observed during the task. In this study, we classified rats into three groups (fast, intermediate, and slow FN-learning groups) based on the number of sessions required to complete learning of the FN task. We then examined whether there was a difference in hippocampal theta power among the fast, intermediate, and slow FN-learning groups, and rats that learned a simple discrimination task (SD group). We observed that compared to the SD group, the slow FN-learning group, but not the fast FN-learning group, showed an increase in hippocampal theta power. In addition, a transient decline of hippocampal theta power occurred in the fast FN-learning group, but not in the slow FN-learning group. These results indicate that the hippocampal theta activity during response inhibition in the FN task differed between fast- and slow-learning rats. Thus, we propose that a difference in learning speed affected hippocampal theta activity during response inhibition under a conflict state.

  20. Devil Declines and Catastrophic Cascades: Is Mesopredator Release of Feral Cats Inhibiting Recovery of the Eastern Quoll?

    PubMed Central

    Fancourt, Bronwyn A.; Hawkins, Clare E.; Cameron, Elissa Z.; Jones, Menna E.; Nicol, Stewart C.

    2015-01-01

    The eastern quoll (Dasyurus viverrinus) is a medium-sized Australian marsupial carnivore that has recently undergone a rapid and severe population decline over the 10 years to 2009, with no sign of recovery. This decline has been linked to a period of unfavourable weather, but subsequent improved weather conditions have not been matched by quoll recovery. A recent study suggested another mechanism: that declines in Tasmanian devil (Sarcophilus harrisii) populations, due to the spread of the fatal Devil Facial Tumour Disease, have released feral cats (Felis catus) from competitive suppression, with eastern quoll declines linked to a subsequent increase in cat sightings. Yet current evidence of intraguild suppression among devils, cats and quolls is scant and equivocal. We therefore assessed the influences of top-down effects on abundance and activity patterns among devils, feral cats and eastern quolls. Between 2011 and 2013, we monitored four carnivore populations using longitudinal trapping and camera surveys, and performed camera surveys at 12 additional sites throughout the eastern quoll’s range. We did not find evidence of a negative relationship between devil and cat abundance, nor of higher cat abundance in areas where devil populations had declined the longest. Cats did not appear to avoid devils spatially; however, there was evidence of temporal separation of cat and devil activity, with reduced separation and increasing nocturnal activity observed in areas where devils had declined the longest. Cats and quolls used the same areas, and there was no evidence that cat and quoll abundances were negatively related. Temporal overlap in observed cat and quoll activity was higher in summer than in winter, but this seasonal difference was unrelated to devil declines. We suggest that cats did not cause the recent quoll decline, but that predation of juvenile quolls by cats could be inhibiting low density quoll populations from recovering their former abundance

  1. Caries decline before fluoride toothpaste was available: earlier and greater decline in the rural north than in southwestern Norway.

    PubMed

    Birkeland, J M; Haugejorden, O

    2001-02-01

    The purpose of this study was to evaluate factors related to caries in 6-17-year-olds in 2 groups of Norwegian counties between 1966 and 1983. The average number of surfaces filled and permanent teeth extracted due to caries declined in the 4 northern counties from 1967. An increase was recorded in the 7 southwestern counties until 1971, then a decline. In the 1960s significantly more surfaces were filled and teeth extracted in the north compared to the southwest. Based on intra-county comparisons, the decline in surfaces treated was greater in the north between 1967 and 1983; 5.4 +/- 0.4 vs 3.7 +/- 0.7, P < 0.01. The averages were 1.9 surfaces treated in the north and the southwest in 1983. Higher infant mortality, lower percentage of people with completed senior secondary education, and more inhabitants per doctor and per dentist in the north indicate a less favorable situation than in the southwest. School-based fluoride programs had been implemented in both groups from the mid-1960s and around 60% participated when fluoride toothpaste became freely marketed in 1971. More fluoride programs and more fluoride tablets were available to children in the north; this may indicate a preventive attitude among dentists. The decline of caries started at different times in different parts of Norway. In the rural north with the most unfavorable situation, the decline was greater and started years before fluoride toothpaste came on to the market. The early decline may partly be ascribed to the school-based fluoride programs, the continued decline to several factors.

  2. Compensatory mechanisms in higher-educated subjects with Alzheimer's disease: a study of 20 years of cognitive decline.

    PubMed

    Amieva, Hélène; Mokri, Hind; Le Goff, Mélanie; Meillon, Céline; Jacqmin-Gadda, Hélène; Foubert-Samier, Alexandra; Orgogozo, Jean-Marc; Stern, Yaakov; Dartigues, Jean-François

    2014-04-01

    A better knowledge of long-term trajectories of cognitive decline is a central feature of the study of the process leading to Alzheimer's dementia. Several factors may mitigate such decline, among which is education, a major risk factor for Alzheimer's disease. The aim of our work was to compare the pattern and duration of clinical trajectories before Alzheimer's dementia in individuals with low and high education within the PAQUID cohort involving 20 years of follow-up. The sample comprises 442 participants with incident Alzheimer's disease (27.2% were male)--171 with low education (mean age=86.2 years; standard deviation=5.3 years) and 271 with higher education (mean age=86.5; standard deviation=5.4)--and 442 control subjects matched according to age, sex and education. At each visit and up to the 20-year follow-up visit, several cognitive and clinical measures were collected and incident cases of Alzheimer's disease clinically diagnosed. The evolution of clinical measures in pre-demented subjects and matched controls was analysed with a semi-parametric extension of the mixed effects linear model. The results show that the first signs of cognitive decline occurred 15 to 16 years before achieving dementia threshold in higher-educated subjects whereas signs occurred at 7 years before dementia in low-educated subjects. There seemed to be two successive periods of decline in higher-educated subjects. Decline started ∼15 to 16 years before dementia with subtle impairment restricted to some cognitive tests and with no impact during the first 7 to 8 years on global cognition, cognitive complaints, or activities of daily living scales. Then, ∼7 years before dementia, global cognitive abilities begin to deteriorate, along with difficulties dealing with complex activities of daily living, the increase in self-perceived difficulties and depressive symptoms. By contrast, lower-educated subjects presented a single period of decline lasting ∼7 years, characterized by

  3. On the decline of biodiversity due to area loss.

    PubMed

    Keil, Petr; Storch, David; Jetz, Walter

    2015-11-17

    Predictions of how different facets of biodiversity decline with habitat loss are broadly needed, yet challenging. Here we provide theory and a global empirical evaluation to address this challenge. We show that extinction estimates based on endemics-area and backward species-area relationships are complementary, and the crucial difference comprises the geometry of area loss. Across three taxa on four continents, the relative loss of species, and of phylogenetic and functional diversity, is highest when habitable area disappears inward from the edge of a region, lower when it disappears from the centre outwards, and lowest when area is lost at random. In inward destruction, species loss is almost proportional to area loss, although the decline in phylogenetic and functional diversity is less severe. These trends are explained by the geometry of species ranges and the shape of phylogenetic and functional trees, which may allow baseline predictions of biodiversity decline for underexplored taxa.

  4. The widespread threat of calcium decline in fresh waters.

    PubMed

    Jeziorski, Adam; Yan, Norman D; Paterson, Andrew M; Desellas, Anna M; Turner, Michael A; Jeffries, Dean S; Keller, Bill; Weeber, Russ C; McNicol, Don K; Palmer, Michelle E; McIver, Kyle; Arseneau, Kristina; Ginn, Brian K; Cumming, Brian F; Smol, John P

    2008-11-28

    Calcium concentrations are now commonly declining in softwater boreal lakes. Although the mechanisms leading to these declines are generally well known, the consequences for the aquatic biota have not yet been reported. By examining crustacean zooplankton remains preserved in lake sediment cores, we document near extirpations of calcium-rich Daphnia species, which are keystone herbivores in pelagic food webs, concurrent with declining lake-water calcium. A large proportion (62%, 47 to 81% by region) of the Canadian Shield lakes we examined has a calcium concentration approaching or below the threshold at which laboratory Daphnia populations suffer reduced survival and fecundity. The ecological impacts of environmental calcium loss are likely to be both widespread and pronounced.

  5. On the decline of biodiversity due to area loss

    PubMed Central

    Keil, Petr; Storch, David; Jetz, Walter

    2015-01-01

    Predictions of how different facets of biodiversity decline with habitat loss are broadly needed, yet challenging. Here we provide theory and a global empirical evaluation to address this challenge. We show that extinction estimates based on endemics–area and backward species–area relationships are complementary, and the crucial difference comprises the geometry of area loss. Across three taxa on four continents, the relative loss of species, and of phylogenetic and functional diversity, is highest when habitable area disappears inward from the edge of a region, lower when it disappears from the centre outwards, and lowest when area is lost at random. In inward destruction, species loss is almost proportional to area loss, although the decline in phylogenetic and functional diversity is less severe. These trends are explained by the geometry of species ranges and the shape of phylogenetic and functional trees, which may allow baseline predictions of biodiversity decline for underexplored taxa. PMID:26575347

  6. Infectious diseases subspecialty: declining demand challenges and opportunities.

    PubMed

    Chandrasekar, Pranatharthi; Havlichek, Daniel; Johnson, Leonard B

    2014-12-01

    Recent match results from the National Resident Matching Program for the subspecialty of infectious diseases show an ongoing decline in the number of fellowship positions filled, and, more important, in the number of applicants, particularly from the pool of international medical graduates. The main reasons for this declining application rate are unclear; in the absence of hard data, we present our viewpoint on this issue. Difficulties in securing visas for permanent residency in the United States, perception of a limited job market, and the explosive growth in the number of hospitalist positions may be important contributing factors. Infectious Diseases Society of America members need to focus on medical students and medical residents in their formative years. We present potential solutions to this problem of declining interest in the field of infectious diseases.

  7. Declining populations of the fingernail clam Musculium transversum in the upper Mississippi River

    USGS Publications Warehouse

    Wilson, D.M.; Naimo, T.J.; Weiner, J.G.; Anderson, R.V.; Sandheinrich, M.B.; Sparks, R.E.

    1995-01-01

    We examined recent temporal trends in the abundance of fingernail clams Musculium transversum (formerly Sphaerium transversum) in the upper Mississippi River. Historical data on densities of fingernail clams were obtained from regional scientists and published literature. We also sampled benthos in six navigation pools in summer 1991, finding very few fingernail clams. The combined data set, including historical data and sampling results, extended from 1973 to 1992 and was sufficient to statistically evaluate trends in densities of fingernail clams in eight pools. Populations of fingernail clams declined significantly in five of the eight pools examined (Pools 2, 5, 7, 9, and 19), which spanned a 700-km reach of river from St. Paul, Minnesota, to Keokuk, Iowa. Densities in Pool 19, which had the longest historical record on fingernail clam abundance, averaged 30 000 m super(-2) in 1985 and progressively declined to zero in 1990. Combined data from all eight pools showed a significant decline in abundance of fingernail clams. An evaluation of potential causal factors led us to hypothesize that the population declines in Pools 2 to 9 were linked to point-source pollution rather than to dredging activity or commercial navigation traffic. In Pool 19, the declines of fingernail clams may have resulted from low-flow conditions during drought periods, but the causal mechanisms by which low flow influences fingernail clam abundance are unclear. The decrease in fingernail clam populations may adversely affect certain fish and wildlife, such as migrating lesser scaup Aythya affinis, which feed heavily on the small mollusk. Moreover, the decreases in populations of this pollution-sensitive mollusk may signal a large-scale deterioration in the health of this riverine ecosystem.

  8. Rapid Decline of a Grassland System and Its Ecological and Conservation Implications

    PubMed Central

    Ceballos, Gerardo; Davidson, Ana; List, Rurik; Pacheco, Jesús; Manzano-Fischer, Patricia; Santos-Barrera, Georgina; Cruzado, Juan

    2010-01-01

    One of the most important conservation issues in ecology is the imperiled state of grassland ecosystems worldwide due to land conversion, desertification, and the loss of native populations and species. The Janos region of northwestern Mexico maintains one of the largest remaining black-tailed prairie dog (Cynomys ludovicianus) colony complexes in North America and supports a high diversity of threatened and endangered species. Yet, cattle grazing, agriculture, and drought have greatly impacted the region. We evaluated the impact of human activities on the Janos grasslands, comparing changes in the vertebrate community over the last two decades. Our results reveal profound, rapid changes in the Janos grassland community, demonstrating large declines in vertebrate abundance across all taxonomic groups. We also found that the 55,000 ha prairie dog colony complex has declined by 73% since 1988. The prairie dog complex has become increasingly fragmented, and their densities have shown a precipitous decline over the years, from an average density of 25 per ha in 1988 to 2 per ha in 2004. We demonstrated that prairie dogs strongly suppressed woody plant encroachment as well as created open grassland habitat by clearing woody vegetation, and found rapid invasion of shrubland once the prairie dogs disappeared from the grasslands. Comparison of grasslands and shrublands showed markedly different species compositions, with species richness being greatest when both habitats were considered together. Our data demonstrate the rapid decline of a grassland ecosystem, and documents the dramatic loss in biodiversity over a very short time period concomitant with anthropogenic grassland degradation and the decline of a keystone species. PMID:20066035

  9. Gradual decline in mobility with the adoption of food production in Europe

    PubMed Central

    Ruff, Christopher B.; Holt, Brigitte; Niskanen, Markku; Sladek, Vladimir; Berner, Margit; Garofalo, Evan; Garvin, Heather M.; Hora, Martin; Junno, Juho-Antti; Schuplerova, Eliska; Vilkama, Rosa; Whittey, Erin

    2015-01-01

    Increased sedentism during the Holocene has been proposed as a major cause of decreased skeletal robusticity (bone strength relative to body size) in modern humans. When and why declining mobility occurred has profound implications for reconstructing past population history and health, but it has proven difficult to characterize archaeologically. In this study we evaluate temporal trends in relative strength of the upper and lower limb bones in a sample of 1,842 individuals from across Europe extending from the Upper Paleolithic [11,000–33,000 calibrated years (Cal y) B.P.] through the 20th century. A large decline in anteroposterior bending strength of the femur and tibia occurs beginning in the Neolithic (∼4,000–7,000 Cal y B.P.) and continues through the Iron/Roman period (∼2,000 Cal y B.P.), with no subsequent directional change. Declines in mediolateral bending strength of the lower limb bones and strength of the humerus are much smaller and less consistent. Together these results strongly implicate declining mobility as the specific behavioral factor underlying these changes. Mobility levels first declined at the onset of food production, but the transition to a more sedentary lifestyle was gradual, extending through later agricultural intensification. This finding only partially supports models that tie increased sedentism to a relatively abrupt Neolithic Demographic Transition in Europe. The lack of subsequent change in relative bone strength indicates that increasing mechanization and urbanization had only relatively small effects on skeletal robusticity, suggesting that moderate changes in activity level are not sufficient stimuli for bone deposition or resorption. PMID:26060299

  10. Test of the invasive pathogen hypothesis of bumble bee decline in North America

    PubMed Central

    Cameron, Sydney A.; Lim, Haw Chuan; Lozier, Jeffrey D.; Duennes, Michelle A.; Thorp, Robbin

    2016-01-01

    Emergent fungal diseases are critical factors in global biodiversity declines. The fungal pathogen Nosema bombi was recently found to be widespread in declining species of North American bumble bees (Bombus), with circumstantial evidence suggesting an exotic introduction from Europe. This interpretation has been hampered by a lack of knowledge of global genetic variation, geographic origin, and changing prevalence patterns of N. bombi in declining North American populations. Thus, the temporal and spatial emergence of N. bombi and its potential role in bumble bee decline remain speculative. We analyze Nosema prevalence and genetic variation in the United States and Europe from 1980, before an alleged introduction in the early 1990s, to 2011, extracting Nosema DNA from Bombus natural history collection specimens from across this time period. Nosema bombi prevalence increased significantly from low detectable frequency in the 1980s to significantly higher frequency in the mid- to late-1990s, corresponding to a period of reported massive infectious outbreak of N. bombi in commercial bumble bee rearing stocks in North America. Despite the increased frequency, we find no conclusive evidence of an exotic N. bombi origin based on genetic analysis of global Nosema populations; the widespread Nosema strain found currently in declining United States bumble bees was present in the United States before commercial colony trade. Notably, the US N. bombi is not detectably different from that found predominantly throughout Western Europe, with both regions characterized by low genetic diversity compared with high levels of diversity found in Asia, where commercial bee breeding activities are low or nonexistent. PMID:27044096

  11. Test of the invasive pathogen hypothesis of bumble bee decline in North America.

    PubMed

    Cameron, Sydney A; Lim, Haw Chuan; Lozier, Jeffrey D; Duennes, Michelle A; Thorp, Robbin

    2016-04-19

    Emergent fungal diseases are critical factors in global biodiversity declines. The fungal pathogenNosema bombiwas recently found to be widespread in declining species of North American bumble bees (Bombus), with circumstantial evidence suggesting an exotic introduction from Europe. This interpretation has been hampered by a lack of knowledge of global genetic variation, geographic origin, and changing prevalence patterns ofN. bombiin declining North American populations. Thus, the temporal and spatial emergence ofN. bombiand its potential role in bumble bee decline remain speculative. We analyzeNosemaprevalence and genetic variation in the United States and Europe from 1980, before an alleged introduction in the early 1990s, to 2011, extractingNosemaDNA fromBombusnatural history collection specimens from across this time period.Nosema bombiprevalence increased significantly from low detectable frequency in the 1980s to significantly higher frequency in the mid- to late-1990s, corresponding to a period of reported massive infectious outbreak ofN. bombiin commercial bumble bee rearing stocks in North America. Despite the increased frequency, we find no conclusive evidence of an exoticN. bombiorigin based on genetic analysis of globalNosemapopulations; the widespreadNosemastrain found currently in declining United States bumble bees was present in the United States before commercial colony trade. Notably, the USN. bombiis not detectably different from that found predominantly throughout Western Europe, with both regions characterized by low genetic diversity compared with high levels of diversity found in Asia, where commercial bee breeding activities are low or nonexistent.

  12. NFE2L2 pathway polymorphisms and lung function decline in chronic obstructive pulmonary disease.

    PubMed

    Sandford, Andrew J; Malhotra, Deepti; Boezen, H Marike; Siedlinski, Mateusz; Postma, Dirkje S; Wong, Vivien; Akhabir, Loubna; He, Jian-Qing; Connett, John E; Anthonisen, Nicholas R; Paré, Peter D; Biswal, Shyam

    2012-08-01

    An oxidant-antioxidant imbalance in the lung contributes to the development of chronic obstructive pulmonary disease (COPD) that is caused by a complex interaction of genetic and environmental risk factors. Nuclear erythroid 2-related factor 2 (NFE2L2 or NRF2) is a critical molecule in the lung's defense mechanism against oxidants. We investigated whether polymorphisms in the NFE2L2 pathway affected the rate of decline of lung function in smokers from the Lung Health Study (LHS)(n = 547) and in a replication set, the Vlagtwedde-Vlaardingen cohort (n = 533). We selected polymorphisms in NFE2L2 in genes that positively or negatively regulate NFE2L2 transcriptional activity and in genes that are regulated by NFE2L2. Polymorphisms in 11 genes were significantly associated with rate of lung function decline in the LHS. One of these polymorphisms, rs11085735 in the KEAP1 gene, was previously shown to be associated with the level of lung function in the Vlagtwedde-Vlaardingen cohort but not with decline of lung function. Of the 23 associated polymorphisms in the LHS, only rs634534 in the FOSL1 gene showed a significant association in the Vlagtwedde-Vlaardingen cohort with rate of lung function decline, but the direction of the association was not consistent with that in the LHS. In summary, despite finding several nominally significant polymorphisms in the LHS, none of these associations were replicated in the Vlagtwedde-Vlaardingen cohort, indicating lack of effect of polymorphisms in the NFE2L2 pathway on the rate of decline of lung function.

  13. Rapid decline of a grassland system and its ecological and conservation implications.

    PubMed

    Ceballos, Gerardo; Davidson, Ana; List, Rurik; Pacheco, Jesús; Manzano-Fischer, Patricia; Santos-Barrera, Georgina; Cruzado, Juan

    2010-01-06

    One of the most important conservation issues in ecology is the imperiled state of grassland ecosystems worldwide due to land conversion, desertification, and the loss of native populations and species. The Janos region of northwestern Mexico maintains one of the largest remaining black-tailed prairie dog (Cynomys ludovicianus) colony complexes in North America and supports a high diversity of threatened and endangered species. Yet, cattle grazing, agriculture, and drought have greatly impacted the region. We evaluated the impact of human activities on the Janos grasslands, comparing changes in the vertebrate community over the last two decades. Our results reveal profound, rapid changes in the Janos grassland community, demonstrating large declines in vertebrate abundance across all taxonomic groups. We also found that the 55,000 ha prairie dog colony complex has declined by 73% since 1988. The prairie dog complex has become increasingly fragmented, and their densities have shown a precipitous decline over the years, from an average density of 25 per ha in 1988 to 2 per ha in 2004. We demonstrated that prairie dogs strongly suppressed woody plant encroachment as well as created open grassland habitat by clearing woody vegetation, and found rapid invasion of shrubland once the prairie dogs disappeared from the grasslands. Comparison of grasslands and shrublands showed markedly different species compositions, with species richness being greatest when both habitats were considered together. Our data demonstrate the rapid decline of a grassland ecosystem, and documents the dramatic loss in biodiversity over a very short time period concomitant with anthropogenic grassland degradation and the decline of a keystone species.

  14. Demography and decline of the Mentasta Caribou Herd, Alaska

    USGS Publications Warehouse

    Jenkins, Kurt J.; Barten, Neil L.

    2005-01-01

    We evaluated population trends in the Mentasta caribou (Rangifer tarandus (L., 1758)) herd in Wrangell a?? St. Elias National Park and Preserve, Alaska, from 1990 to 1997 and determined factors contributing to its decline. We postulated that predation-related mortality of adult females and juveniles was the proximate cause of the decline, and that survival of juvenile caribou reflected interactions with winter severity, calving distribution, timing of births, density of caribou, and physical condition of neonates at birth. The population declined at its greatest rate from 1990 to 1993 (r = a??0.32) and at a lower rate from 1994 to 1997 (r = a??0.09). Recruitment (number of calves/100 females during September) averaged 4/100 during the rapid population decline from 1990 to 1993 and 13/100 from 1994 to 1997. Parturition rate of adult females ranged from 65% to 97%. Survival of adult females and juveniles ranged from 0.77 to 0.86 and from 0.00 to 0.22, respectively. Approximately 43%, 59%, and 79% of all juvenile mortality occurred by 1, 2, and 4 weeks of age, respectively. We confirmed predation-related mortality as the primary proximate cause of population decline, with gray wolves (Canis lupus L., 1758), bears (species of the genus Ursus L., 1758), and other predators accounting for 57%, 38%, and 5%, respectively, of all juvenile mortality, and bears causing disproportionate mortality among 0- to 1-week-old neonates. We supported the hypotheses that timing of birth and habitat conditions at the birth site, particularly mottled snow patterns, affected vulnerability and survival of neonates, and birth mass affected survival of juveniles through summer. We speculate that the population will continue to decline before reaching a low-density equilibrium that is sustained by density-dependent changes in the functional responses of predators.

  15. Brain network changes and memory decline in aging.

    PubMed

    Beason-Held, Lori L; Hohman, Timothy J; Venkatraman, Vijay; An, Yang; Resnick, Susan M

    2016-06-18

    One theory of age-related cognitive decline proposes that changes within the default mode network (DMN) of the brain impact the ability to successfully perform cognitive operations. To investigate this theory, we examined functional covariance within brain networks using regional cerebral blood flow data, measured by (15)O-water PET, from 99 participants (mean baseline age 68.6 ± 7.5) in the Baltimore Longitudinal Study of Aging collected over a 7.4 year period. The sample was divided in tertiles based on longitudinal performance on a verbal recognition memory task administered during scanning, and functional covariance was compared between the upper (improvers) and lower (decliners) tertile groups. The DMN and verbal memory networks (VMN) were then examined during the verbal memory scan condition. For each network, group differences in node-to-network coherence and individual node-to-node covariance relationships were assessed at baseline and in change over time. Compared with improvers, decliners showed differences in node-to-network coherence and in node-to-node relationships in the DMN but not the VMN during verbal memory. These DMN differences reflected greater covariance with better task performance at baseline and both increasing and declining covariance with declining task performance over time for decliners. When examined during the resting state alone, the direction of change in DMN covariance was similar to that seen during task performance, but node-to-node relationships differed from those observed during the task condition. These results suggest that disengagement of DMN components during task performance is not essential for successful cognitive performance as previously proposed. Instead, a proper balance in network processes may be needed to support optimal task performance.

  16. Atrial Fibrillation, Neurocognitive Decline and Gene Expression After Cardiopulmonary Bypass

    PubMed Central

    Dalal, Rahul S.; Sabe, Ashraf A.; Elmadhun, Nassrene Y.; Ramlawi, Basel; Sellke, Frank W.

    2015-01-01

    OBJECTIVE Atrial fibrillation and neurocognitive decline are common complications after cardiopulmonary bypass. By utilizing genomic microarrays we investigate whether gene expression is associated with postoperative atrial fibrillation and neurocognitive decline. METHODS Twenty one cardiac surgery patients were prospectively matched and underwent neurocognitive assessments pre-operatively and four days postoperatively. The whole blood collected in the pre-cardiopulmonary bypass, 6 hours after-cardiopulmonary bypass, and on the 4th postoperative day was hybridized to Affymetrix Gene Chip U133 Plus 2.0 Microarrays. Gene expression in patients who developed postoperative atrial fibrillation and neurocognitive decline (n=6; POAF+NCD) was compared with gene expression in patients with postoperative atrial fibrillation and normal cognitive function (n=5; POAF+NORM) and patients with sinus rhythm and normal cognitive function (n=10; SR+NORM). Regulated genes were identified using JMP Genomics 4.0 with a false discovery rate of 0.05 and fold change of >1.5 or <-1.5. RESULTS Eleven patients developed postoperative atrial fibrillation. Six of these also developed neurocognitive decline. Of the 12 patients with sinus rhythm, only 2 developed neurocognitive decline. POAF+NCD patients had unique regulation of 17 named genes preoperatively, 60 named genes six hours after cardiopulmonary bypass, and 34 named genes four days postoperatively (P<0.05) compared with normal patients. Pathway analysis demonstrated that these genes are involved in cell death, inflammation, cardiac remodeling and nervous system function. CONCLUSION Patients who developed postoperative atrial fibrillation and neurocognitive decline after cardiopulmonary bypass may have differential genomic responses compared to normal patients and patients with only postoperative atrial fibrillation, suggesting common pathophysiology for these conditions. Further exploration of these genes may provide insight into the

  17. Decline in maternal mortality in Matlab, Bangladesh: a cautionary tale.

    PubMed

    Ronsmans, C; Vanneste, A M; Chakraborty, J; van Ginneken, J

    This study examines the impact of the Maternal-Child Health and Family Planning (MCH-FP) program in the Matlab, Bangladesh. Data were obtained from the Matlab surveillance system for treatment and comparison areas. This study reports the trends in maternal mortality since 1976. The MCH-FP area received extensive services in health and family planning since 1977. Services included trained traditional birth attendants and essential obstetric care from government district hospitals and a large number of private clinics. Geographic ease of access to essential obstetric care varied across the study area. Access was most difficult in the northern sector of the MCH-FP area. Contraception was made available through family welfare centers. Tetanus immunization was introduced in 1979. Door-to-door contraceptive services were provided by 80 female community health workers on a twice-monthly basis. In 1987, a community-based maternity care program was added to existing MCH-FP services in the northern treatment area. The demographic surveillance system began collecting data in 1966. During 1976-93 there were 624 maternal deaths among women aged 15-44 years in Matlab (510/100,000 live births). 72.8% of deaths were due to direct obstetric causes: postpartum hemorrhage, induced abortion, eclampsia, dystocia, and postpartum sepsis. Maternal mortality declined in a fluctuating fashion in both treatment and comparison areas. Direct obstetric mortality declined at about 3% per year. After 1987, direct obstetric mortality declined in the north by almost 50%. After the 1990 program expansion in the south, maternal mortality declined, though not significantly, in the south. Maternal mortality declined in the south comparison area during 1987-89 and stabilized. The comparison area of the north showed no decline.

  18. Decline in renal functioning is associated with longitudinal decline in global cognitive functioning, abstract reasoning and verbal memory

    PubMed Central

    Davey, Adam; Elias, Merrill F.; Robbins, Michael A.; Seliger, Stephen L.; Dore, Gregory A.

    2013-01-01

    Background Decreased estimated glomerular filtration rate (eGFR) and higher serum creatinine (sCR) levels have been associated with longitudinal decline in global mental status measures. Longitudinal data describing change in multiple domains of cognitive functioning are needed in order to determine which specific abilities are most affected in individuals with impaired renal function. Methods We conducted a 5-year longitudinal study with 590 community-living individuals (mean age 62.1 years, 60.2% female, 93.2% white, 11.4% with diabetes mellitus, mean eGFR 78.4 mL/min/1.73 m²) free from dementia, acute stroke and end-stage renal disease. To measure longitudinal change-over-time, cognitive performance measures were regressed on eGFR adjusting for baseline eGFR and cognitive performance, comorbidity and vascular risk factors. Outcome measures were scores from 17 separate tests of cognitive abilities that were used to index 5 theoretically relevant domains: verbal episodic memory, visual-spatial organization and memory, scanning and tracking, working memory and similarities (abstract reasoning). Results Declines in eGFR values were associated with cognitive declines, when adjusted for eGFR and cognitive function scores at baseline. Change in renal functioning over time was related to change observed in global cognitive ability [b = 0.21SD decline per unit ln(eGFR), 95% CI: 0.04–0.38, P = .018], verbal episodic memory [b = 0.28 SD decline per unit ln(eGFR), 95% CI: 0.02–0.54, P = 0.038] and abstract reasoning [b = 0.36 SD decline per unit ln(eGFR), 95% CI: 0.04–0.67, P = 0.025]. Decline in cognitive functioning in association with declining renal functioning was observed despite statistical adjustment for demographic variables and CVD risk factors and the exclusion of persons with dementia or a history of acute stroke. Conclusions Early detection of mild to moderate kidney disease is an important public health concern with regard to cognitive decline. PMID

  19. Towards the Understanding of Recent Lake Decline in the Yangtze Basin

    NASA Astrophysics Data System (ADS)

    Wang, J.; Sheng, Y.; Wada, Y.

    2014-12-01

    In the era of Anthropocene, lakes as essential stocks of terrestrial water resources are subject to increasing vulnerability from both climatic variations and human activities. Our recent study reveals a decadal area decline among the largest cluster of freshwater lakes in East Asia, distributed across the Yangtze River Basin downstream of China's Three Gorges Dam (TGD). The observed lake decline, a cumulative rate of 7.4% (~850 km2) from 2000 to 2011, concurred with enduring meteorological drought, continuous population growth, and extensive human water regulation (e.g., the TGD). The decreasing trend was tested significant in all seasons, leading to an evident phase drop of the average annual lake cycle before and after the TGD operation. The most substantial decline in the post-TGD period appears in fall (1.1% yr-1), which intriguingly coincides with the TGD water storage season. Motivated by such findings, this paper provides a comprehensive diagnosis of the potential TGD impacts on the Yangtze-connected downstream lake system, in comparison to the concurrent contributions from local meteorological variations and human water consumption. Results uncover an altered inundation regime of the downstream lake system induced by TGD's water regulation, manifested as evident lake area decrease in fall and increase in spring and winter. As the most substantial influence, reduced lake area in fall explains ~20-80% of the observed post-TGD decline. Concurrent Yangtze channel erosion slightly reinforced the area decrease in fall while counteracting ~30% of the area increase in winter. Human water consumption accumulated through the local river network led to constant discharge reduction, which equals another ~80% of the TGD-induced lake decline in fall and completely counteracts the TGD-induced lake area increase in winter. However, human water consumption only adds minor contribution (< 6%) to the post-TGD lake decline due to slow increasing rates during 2000-2011. The

  20. In the aging housefly aconitase is the only citric acid cycle enzyme to decline significantly.

    PubMed

    Yarian, Connie S; Sohal, Rajindar S

    2005-04-01

    The main objective of this study was to determine if the activities of the mitochondrial citric acid cycle enzymes are altered during the normal aging process. Flight muscle mitochondria of houseflies of different ages were used as a model system because of their apparent age-related decline in bioenergetic efficiency, evident as a failure of flying ability. The maximal activities of each of the citric acid cycle enzymes were determined in preparations of mitochondria from flies of relatively young, middle, and old age. Aconitase was the only enzyme exhibiting altered activity during aging. The maximal activity of aconitase from old flies was decreased by 44% compared to that from young flies while the other citric acid cycle enzymes showed no change in activity with age. It is suggested that the selective age-related decrease in aconitase activity is likely to contribute to a decline in the efficiency of mitochondrial bioenergetics, as well as result in secondary effects associated with accumulation of citrate and redox-active iron.

  1. Rapid cognitive decline: not always Creutzfeldt-Jakob disease.

    PubMed

    Randall, A; Ellis, R; Hywel, B; Davies, R R; Alusi, S H; Larner, A J

    2015-01-01

    A patient with rapidly progressive cognitive decline over an approximately four month period was suspected to have sporadic Creutzfeldt-Jakob disease. Features thought to support this diagnosis included psychiatric symptoms (anxiety and depression), visual hallucinations and a visual field defect. However, the finding of papilloedema broadened the differential diagnosis. Although standard brain imaging and electroencephalography had shown only non-specific abnormalities, subsequent cerebral angiography disclosed an intracranial dural arteriovenous fistula. Following embolisation, the patient made a good functional recovery. Intracranial dural arteriovenous fistula merits consideration in any patient with subacute cognitive decline, and should be included in the differential diagnosis of sporadic Creutzfeldt-Jakob disease.

  2. [Fertility decline in Colombia: expression of a profound social change].

    PubMed

    De Llinas, H M

    1983-01-01

    Demographers have identified 3 phases in the evolution of human population growth: 1) high mortality and high fertility resulting in very slow growth, 2) declining mortality and high fertility, resulting in rapid growth, and 3) declining mortality and fertility, resulting in slower growth. From the beginning of the century until the 1930s, Colombia was in the 1st phase, while the greatest mortality declines were registered from 1930-60. Fertility did not decline commensurately, and from 1951-64 the rate of population increase was 3.14%. The National Fertility Survey in 1969 and the 1973 census indicated that the country had at last begun its fertility decline. The 1969 survey showed that the total fertility rate (TFR) had dropped from 7.0 in the early 1960s to 6.0 in 1967-68, with fertility declining in both rural and urban areas. The 1973 census showed a rate of growth of 2.8% and an average number of children/woman of 4.7, showing that the fertility decline was structural and reflected profound changes in the values, norms, and attitudes regarding children of the Colombian population. Urbanization, the increased educational level and labor force participation of women, and the influence of the mass media in propagating the values of a consumer society are factors in the reduction of family size. Fertility differentials by region and social group have been declining progressively. The TFR in 1960-64 was 7.0 overall, 6.1 in urban areas, and 7.9 in rural areas, while in 1980 it was 3.6 overall, 3.0 in urban areas, and 5.1 in rural areas. In 1968-69, the TFR was 7.8 in the Atlantic region, 7.9 in the Oriental, 6.8 in the Central, 5.9 in the Pacific, and 4.5 in Bogota, while in 1980 it was 4.1 in the Atlantic, 4.0 in the Oriental, 3.5 in the Central, 3.3 in the Pacific, and 2.8 in Bogota. The number of women using family planning programs increased from 83 in 1965 to 1,790,484 in 1980. The proportion using contraception increased from 53% in 1976 to 55% in 1980. The

  3. Genetic uniformity and the decline of red spruce

    SciTech Connect

    Not Available

    1989-05-01

    This brief note examines current research that suggests genetic uniformity as a cause of red spruce decline. Although acid rain and ozone have been implicated in the decline of the species, dieback has been observed evening areas where pollution is low. In addition, the dieback is not observed in other species. Researchers have analyzed the seeds of approximately 500 red spruce trees representing 13 boreal and Montane populations from southern Appalachia to Canada. Of 42 gene loci examined, on the average only 8% of the genes were heterozygousand only 31% were polymorphic.

  4. Amphibian decline: An integrated analysis of multiple stressor effects

    USGS Publications Warehouse

    Linder, G.; Krest, S.K.; Sparling, D. W.; Linder, G.; Krest, S.K.; Sparling, D.W.

    2003-01-01

    Capturing the attention and imagination of the public and the scientific community alike, the mysterious decline in amphibian populations drew scientists and resource managers from ecotoxicology and chemistry, ecology and field biology, conservation biology, and natural resource policy to a SETAC–Johnson Foundation workshop. Facilitating environmental stewardship, increasing capacity of the sciences to explain complex stressors, and educating the public on relationships among communities of all types motivated these experts to address amphibian decline and the role of various stressors in these losses.

  5. Sensorineural Organs Dysfunction and Cognitive Decline: A Review Article

    PubMed Central

    Wongrakpanich, Supakanya; Petchlorlian, Aisawan; Rosenzweig, Andrew

    2016-01-01

    Vision, hearing, olfaction, and cognitive function are essential components of healthy and successful aging. Multiple studies demonstrate relationship between these conditions with cognitive function. The present article focuses on hearing loss, visual impairment, olfactory loss, and dual sensory impairments in relation to cognitive declination and neurodegenerative disorders. Sensorineural organ impairment is a predictive factor for mild cognitive impairment and neurodegenerative disorders in the elderly. We recommend early detection of sensorineural dysfunction by history, physical examination, and screening tests. Assisted device and early cognitive rehabilitation may be beneficial. Future research is warranted in order to explore advanced treatment options and method to slow progression for cognitive declination and sensorineural organ impairment. PMID:28053826

  6. How Personal Is the Political? Democratic Revolution and Fertility Decline

    PubMed Central

    Bailey, Amy Kate

    2010-01-01

    Existing theory has identified the capacity of political revolutions to effect change in a variety of social institutions, although relationships between revolution and many institutions remain unexplored. Using historical data from 22 European and four diaspora countries, I examine the temporal relationship between timing of revolution and onset of fertility decline. I hypothesize that specific kinds of revolutionary events affect fertility by engendering ideological changes in popular understandings of the individual’s relationship to society, and ultimately the legitimacy of couples’ authority over their reproductive capacities. Results demonstrate that popular democratic revolution – but not institutionalized democratic structures – predict the timing of the onset of fertility decline. PMID:19999826

  7. How personal is the political? Democratic revolution and fertility decline.

    PubMed

    Bailey, Amy Kate

    2009-10-01

    Existing theory has identified the capacity of political revolutions to effect change in a variety of social institutions, although relationships between revolution and many institutions remain unexplored. Using historical data from twenty-two European and four diaspora countries, the author examines the temporal relationship between timing of revolution and onset of fertility decline. The author hypothesizes that specific kinds of revolutionary events affect fertility by engendering ideological changes in popular understandings of the individual's relationship to society and ultimately the legitimacy of couples' authority over their reproductive capacities. Results demonstrate that popular democratic revolutions -- but not institutionalized democratic structures -- predict the timing of the onset of fertility decline.

  8. The future of species under climate change: resilience or decline?

    PubMed

    Moritz, Craig; Agudo, Rosa

    2013-08-02

    As climates change across already stressed ecosystems, there is no doubt that species will be affected, but to what extent and which will be most vulnerable remain uncertain. The fossil record suggests that most species persisted through past climate change, whereas forecasts of future impacts predict large-scale range reduction and extinction. Many species have altered range limits and phenotypes through 20th-century climate change, but responses are highly variable. The proximate causes of species decline relative to resilience remain largely obscure; however, recent examples of climate-associated species decline can help guide current management in parallel with ongoing research.

  9. Decline in human immunodeficiency virus seropositivity and seroconversion in US Navy enlisted personnel: 1986 to 1989. Navy HIV Working Group.

    PubMed Central

    Garland, F C; Gorham, E D; Cunnion, S O; Miller, M R; Balazs, L L

    1992-01-01

    The US Navy administered 1,795,578 enzyme-linked immunosorbent assay (ELISA) tests to 848,632 active-duty Navy enlisted personnel during 1986 to 1989. This study identified 2438 human immunodeficiency virus (HIV)-seropositive active-duty enlisted Navy personnel, including 778 seroconverters. Three types of quarterly rates of HIV seropositivity and seroconversion were determined. All three rates declined. This decline could not be explained by changes in the population tested according to age, race, sex, occupation, or geographic location of home port. PMID:1546779

  10. Early-Onset, Regular Cannabis Use Is Linked to IQ Decline

    MedlinePlus

    ... Is Linked to IQ Decline Early-Onset, Regular Cannabis Use Is Linked to IQ Decline Email Facebook ... that cannabis use may harm the developing brain. Cannabis Use Correlates With Cognitive Decline The study participants ...

  11. Ability of university-level education to prevent age-related decline in emotional intelligence.

    PubMed

    Cabello, Rosario; Navarro Bravo, Beatriz; Latorre, José Miguel; Fernández-Berrocal, Pablo

    2014-01-01

    Numerous studies have suggested that educational history, as a proxy measure of active cognitive reserve, protects against age-related cognitive decline and risk of dementia. Whether educational history also protects against age-related decline in emotional intelligence (EI) is unclear. The present study examined ability EI in 310 healthy adults ranging in age from 18 to 76 years using the Mayer-Salovey-Caruso Emotional Intelligence Test (MSCEIT). We found that older people had lower scores than younger people for total EI and for the EI branches of perceiving, facilitating, and understanding emotions, whereas age was not associated with the EI branch of managing emotions. We also found that educational history protects against this age-related EI decline by mediating the relationship between age and EI. In particular, the EI scores of older adults with a university education were higher than those of older adults with primary or secondary education, and similar to those of younger adults of any education level. These findings suggest that the cognitive reserve hypothesis, which states that individual differences in cognitive processes as a function of lifetime intellectual activities explain differential susceptibility to functional impairment in the presence of age-related changes and brain pathology, applies also to EI, and that education can help preserve cognitive-emotional structures during aging.

  12. Measurements of Declination at the Helsinki Magnetic-meteorological Observatory 1844-1853

    NASA Technical Reports Server (NTRS)

    Nevanlinna, Heikki; Ketola, Anneli; Kangas, Tuulikki

    1992-01-01

    A project was started with the goal of putting into computer readable form all the old unpublished magnetic data at the Finnish Meteorological Institute (FMI), the successor of the Helsinki magnetic-meteorological observatory. Altogether there are available about 2.5 million visual observations of D, H and Z made during the time interval 1844-1905. The first 10 year period (1844-1853) of declination data now converted to electronic form, includes observations made at every tenth minute. The total number of observations is 489,152. We present some examples of declination observations in forms of tables and graphs showing hourly, daily, monthly, and annual means. Secular variations of the declination in 1844-1853 have been extremely linear, showing a steady eastward increase of 8 prime/year that is more than two times larger than the present annual rate of secular change in Finland. The standard deviation of the daily and monthly residuals, after removing the secular variation trend for the whole time period, is about 1 prime, demonstrating the high stability and reliability of the observations. For this reason the data may be suitable for deriving a 3-hour activity index K and daily Ak numbers, giving new information for extending the existing long series of activity characters backwards in time.

  13. Context Memory Decline in Middle Aged Adults is Related to Changes in Prefrontal Cortex Function.

    PubMed

    Kwon, Diana; Maillet, David; Pasvanis, Stamatoula; Ankudowich, Elizabeth; Grady, Cheryl L; Rajah, M Natasha

    2016-06-01

    The ability to encode and retrieve spatial and temporal contextual details of episodic memories (context memory) begins to decline at midlife. In the current study, event-related fMRI was used to investigate the neural correlates of context memory decline in healthy middle aged adults (MA) compared with young adults (YA). Participants were scanned while performing easy and hard versions of spatial and temporal context memory tasks. Scans were obtained at encoding and retrieval. Significant reductions in context memory retrieval accuracy were observed in MA, compared with YA. The fMRI results revealed that overall, both groups exhibited similar patterns of brain activity in parahippocampal cortex, ventral occipito-temporal regions and prefrontal cortex (PFC) during encoding. In contrast, at retrieval, there were group differences in ventral occipito-temporal and PFC activity, due to these regions being more activated in MA, compared with YA. Furthermore, only in YA, increased encoding activity in ventrolateral PFC, and increased retrieval activity in occipital cortex, predicted increased retrieval accuracy. In MA, increased retrieval activity in anterior PFC predicted increased retrieval accuracy. These results suggest that there are changes in PFC contributions to context memory at midlife.

  14. Ear length and kidney function decline after kidney donation.

    PubMed

    Katavetin, Pisut; Watanatorn, Salin; Townamchai, Natavudh; Avihingsanon, Yingyos; Praditpornsilpa, Kearkiat

    2016-11-01

    The preservation of kidney function after kidney donation depends on the kidney reserve - the potential of the remaining kidney to boost their function after loss of the other kidney. In Traditional Chinese Medicine, size and shape of the external ears are examined to evaluate the person's kidney health. We hypothesized that ear size might be a practical yet overlooked marker of kidney reserve. Fifty kidney transplantation donors were participated in this study. The length and width of both ears of all participants were measured during one of the post-donation visits. Pre-donation serum creatinine and post-donation serum creatinine as well as other relevant parameters (age, sex, weight, height, etc.) of the participants were extracted from medical records. The estimated GFR was calculated from serum creatinine, age and sex using the CKD-EPI equation. Ear length negatively associated with %GFR decline after kidney donation. For every 1 cm increase in ear length, it was associated with 5.7% less GFR decline after kidney donation (95% Confidence Interval 0.2 to 11.3, P = 0.04). Ear width, as well as age, sex, body weight, height, body mass index, and pre-donation eGFR did not significantly associate with the GFR decline. Our findings support the notion of Traditional Chinese Medicine that ear morphology may be associated with kidney health and suggest that ear length might be a useful predictor of kidney function decline after kidney donation.

  15. Drought-induced forest decline: causes, scope and implications

    PubMed Central

    Martínez-Vilalta, Jordi; Lloret, Francisco; Breshears, David D.

    2012-01-01

    A large number of episodes of forest mortality associated with drought and heat stress have been detected worldwide in recent decades, suggesting that some of the world's forested ecosystems may be already responding to climate change. Here, we summarize a special session titled ‘Drought-induced forest decline: causes, scope and implications’ within the 12th European Ecological Federation Congress, held in Ávila (Spain) from 25 to 29 September 2011. The session focused on the interacting causes and impacts of die-off episodes at the community and ecosystem levels, and highlighted recent events of drought- and heat-related tree decline, advances in understanding mechanisms and in predicting mortality events, and diverse consequences of forest decline. Talks and subsequent discussion noted a potentially important role of carbon that may be interrelated with plant hydraulics in the multi-faceted process leading to drought-induced mortality; a substantial and yet understudied capacity of many forests to cope with extreme climatic events; and the difficulty of separating climate effects from other anthropogenic changes currently shaping forest dynamics in many regions of the Earth. The need for standard protocols and multi-level monitoring programmes to track the spatio-temporal scope of forest decline globally was emphasized as critical for addressing this emerging environmental issue. PMID:22171020

  16. Are We Sure the Quality of Teacher Candidates is Declining?

    ERIC Educational Resources Information Center

    Gallegos, Arnold M.; Gibson, Harry

    1982-01-01

    Data suggest that self-selection is weeding out the poorer students in the teacher education program at Western Washington University. The grade point average of freshmen, although declining for the university as a whole, is rising in teacher education. (Author/JM)

  17. Coordinated responses to honey bee decline in the USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In response to successive years of high honey bee mortality, the United States Congress mandated the U.S. Department of Agriculture to increase funding for research and education directed at reducing honey bee decline. The funding followed two administrative streams within USDA – one through the USD...

  18. American Family Decline, 1960-1990: A Review and Appraisal.

    ERIC Educational Resources Information Center

    Popenoe, David

    1993-01-01

    Draws from U.S. Census data to review family trends of past 30 years. Appraises evidence for family decline in three areas: demographic, institutional, and cultural. Argues that families have lost functions, power, and authority; that familism as cultural value has diminished; and that people have become less willing to invest time, money, and…

  19. Evaluating Functional Decline in Patients with Multiple Sclerosis

    ERIC Educational Resources Information Center

    Rosenblum, Sara; Weiss, Patrice L.

    2010-01-01

    Multiple Sclerosis (MS) is a disease with a wide-ranging impact on functional status. The aim of the study was to examine the added value of simultaneously evaluating fatigue, personal ADL and handwriting performance as indicators for functional decline among patients with MS. Participants were 50 outpatients with MS and 26 matched healthy…

  20. The Decline in the Economic Rewards to College Education

    ERIC Educational Resources Information Center

    Freeman, R. B.

    1977-01-01

    Analyzes the decline in the economic value of college training, using data from the 1969 and 1974 consumer income tapes from the Current Population Survey. Available from: North-Holland Publishing Company, P.O. Box 211, Amsterdam, The Netherlands; $19.00 annual subscription. (Author/JG)

  1. The Management of Decline in Education: The Case of Quebec.

    ERIC Educational Resources Information Center

    Crespo, Manuel; Hache, Jean B.

    1982-01-01

    Examines the social and organizational contexts of enrollment decline in Quebec (Canada) and describes the management strategies adopted by Quebec school districts to survive within reduced budgets and to try to increase budgets. Proposes a contingency model of the districts' management strategies and discusses the strategies' consequences and…

  2. Decline of red spruce in the Adirondacks, New York

    SciTech Connect

    Scott, J.T.; Siccama, T.G.; Johnson, A.H.; Breisch, A.R.

    1984-01-01

    Thirty-two stands in the spruce-fir forests of Whiteface Mountain in the Adirondacks, originally sampled from 1964-66, were resurveyed in 1982. From 10-25 Bitterlich points were used in each stand in 1982 to obtain an estimate of basal area per hectare. Data were summarized for low elevation (<900m) and high elevation (> or = 900m) forests. Red spruce declined by 40-60% in basal area for the low elevation forests and by 60-70% above 900m. Balsam fir decreased by 35% at high elevations, due to natural disturbance in several of the stands, but was unchanged when only undisturbed stands were considered. The decline of red spruce accounted for about three quarters of the total decrease in basal area for both the high- and low-elevation forests. Spruce seedling frequency for the high-elevation sample decreased by 80%, but was unchanged below 900m. The pattern of spruce decline in the Adirondacks is similar to findings for New England. The cause of the decline is speculative at the time.

  3. Sobering up: A Quantitative Review of Temporal Declines in Expectations

    ERIC Educational Resources Information Center

    Sweeny, Kate; Krizan, Zlatan

    2013-01-01

    Although people's outlook on the future tends to be characterized by hope and optimism, over time this outlook often becomes more dire. We review multiple theoretical accounts of this tendency to "sober up" as feedback about outcomes draws near, and we explicate factors critical to promoting these temporal declines in expectations. We then…

  4. Declining Enrollment, a People Problem (Effective Strategies for Reducing Staffs).

    ERIC Educational Resources Information Center

    Thomas, Donald

    School districts faced with declining enrollments can utilize several strategies for dealing with reductions in force while saving money, minimizing terminations, and creating new opportunities. Schools should be staffed on the basis of midyear projections to avoid too great a degree of overstaffing by year's end. An early retirement plan should…

  5. A Decline in Creativity? It Depends on the Domain

    ERIC Educational Resources Information Center

    Weinstein, Emily C.; Clark, Zachary; DiBartolomeo, Donna J.; Davis, Katie

    2014-01-01

    Earlier studies using psychometric tests have documented declines in creativity over the past several decades. Our study investigated whether and how this apparent trend would replicate through a qualitative investigation using an authentic nontest measure of creativity. Three-hundred and fifty-four visual artworks and 50 creative writing works…

  6. Evidence of disease-related amphibian decline in Colorado

    USGS Publications Warehouse

    Muths, Erin; Corn, Paul Stephen; Pessier, Allan P.; Green, D. Earl

    2003-01-01

    The recent discovery of a pathogenic fungus (Batrachochytrium dendrobatidis) associated with declines of frogs in the American and Australian tropics, suggests that at least the proximate cause, may be known for many previously unexplained amphibian declines. We have monitored boreal toads in Colorado since 1991 at four sites using capturea??recapture of adults and counts of egg masses to examine the dynamics of this metapopulation. Numbers of male toads declined in 1996 and 1999 with annual survival rate averaging 78% from 1991 to 1994, 45% in 1995 and 3% between 1998 and 1999. Numbers of egg masses also declined. An etiological diagnosis of chytridiomycosis consistent with infections by the genus Batrachochytrium was made in six wild adult toads. Characteristic histomorphological features (i.e. intracellular location, shape of thalli, presence of discharge tubes and rhizoids) of chytrid organisms, and host tissue response (acanthosis and hyperkeratosis) were observed in individual toads. These characteristics were indistinguishable from previously reported mortality events associated with chytrid fungus. We also observed epizootiological features consistent with mortality events associated with chytrid fungus: an increase in the ratio of female:male toads captured, an apparent spread of mortalities within the metapopulation and mortalities restricted to post metamorphic animals. Eleven years of population data suggest that this metapopulation of toads is in danger of extinction, pathological and epizootiological evidence indicates that B. dendrobatidis has played a proximate role in this process

  7. Is Occupational Mobility Declining in the United States?

    ERIC Educational Resources Information Center

    Rytina, Steven

    2000-01-01

    Trends in occupational mobility for U.S. males, 1972-90, were analyzed using three occupational scales providing different indicators of occupational status and social stratification. Results indicate stable or increasing rigidity in U.S. occupational stratification, with a decline in education's importance, both as key to achieving high rank and…

  8. IQ Decline Following Early Unilateral Brain Injury: A Longitudinal Study

    ERIC Educational Resources Information Center

    Levine, Susan C.; Kraus, Ruth; Alexander, Erin; Suriyakham, Linda Whealton; Huttenlocher, Peter R.

    2005-01-01

    We examine whether children with early unilateral brain injury show an IQ decline over the course of development. Fifteen brain injured children were administered an IQ test once before age 7 and again several years later. Post-7 IQ scores were significantly lower than pre-7 IQ scores. In addition, pre-7 IQ scores were lower for children with…

  9. Declining Health Behavior of Adolescents: A Measure of Alienation.

    ERIC Educational Resources Information Center

    Crase, Darrell

    1981-01-01

    Cites statistics on such adolescent problems as pregnancy, drugs, and obesity as evidence of the serious neglect and alienation of this age group in an era of family instability and declining social roles for youth. Urges educators to give concerted attention to the physical, mental, and health needs of adolescents. (SJL)

  10. Factors Contributing to Declining Enrollments at the University of Transkei.

    ERIC Educational Resources Information Center

    Imenda, S. N.; Kongolo, M.; Grewal, A. S.

    2002-01-01

    Surveyed students about their decision to enroll at the Unitersity of Transkei in an attempt to determine causes for declining enrollment. Found that career directions and affordability were main criteria. Public image and stability, staff quality, facilities and resources, administrative efficiency, staff friendliness, admissions/registration…

  11. Stagnation in Mortality Decline among Elders in the Netherlands

    ERIC Educational Resources Information Center

    Janssen, Fanny; Nusselder, Wilma J.; Looman, Caspar W. N.; Mackenbach, Johan P.; Kunst, Anton E.

    2003-01-01

    Purpose: This study assesses whether the stagnation of old-age (80+) mortality decline observed in The Netherlands in the 1980s continued in the 1990s and determines which factors contributed to this stagnation. Emphasis is on the role of smoking. Design and Methods: Poisson regression analysis with linear splines was applied to total and…

  12. Reasons for Declining Preconception Expanded Carrier Screening Using Genome Sequencing.

    PubMed

    Gilmore, Marian J; Schneider, Jennifer; Davis, James V; Kauffman, Tia L; Leo, Michael C; Bergen, Kellene; Reiss, Jacob A; Himes, Patricia; Morris, Elissa; Young, Carol; McMullen, Carmit; Wilfond, Benjamin S; Goddard, Katrina A B

    2017-03-17

    Genomic carrier screening can identify more disease-associated variants than existing carrier screening methodologies, but its utility from patients' perspective is not yet established. A randomized controlled trial for preconception genomic carrier screening provided an opportunity to understand patients' decisions about whether to accept or decline testing. We administered a survey to potential genomic carrier screening recipients who declined participation (N = 240) to evaluate their reasons for doing so. Two thirds of women declined participation. We identified major themes describing reasons these individuals declined to participate; the most common were time limitation, lack of interest, not wanting to know the information, and potential cause of worry or anxiety. Most women eligible for genomic carrier screening indicated that their reasons for opting out were due to logistical issues rather than opposing the rationale for testing. As expanded carrier screening and genomic sequencing become a more routine part of clinical care, it is anticipated there will be variable uptake from individuals for this testing. Thus, the advancement of clinical carrier screening from single genes, to expanded screening panels, to an exome- or genome-wide platform, will require approaches that respect individual choice to receive genetic testing for reproductive risk assessment.

  13. Cerebrospinal fluid biomarkers mirror rate of cognitive decline.

    PubMed

    Rolstad, Sindre; Berg, Anne Ingeborg; Bjerke, Maria; Johansson, Boo; Zetterberg, Henrik; Wallin, Anders

    2013-01-01

    The ability to predict future decline in cognitive systems using the cerebrospinal fluid (CSF) biomarkers 42 amino acid form of amyloid-β (Aβ42) and total tau (T-tau) is not fully understood. In a clinical sample ranging from cognitively healthy to dementia (n = 326), linear regression models were performed in order to investigate the ability of CSF biomarkers to predict cognitive decline in all cognitive domains from baseline to 2-year follow-up. Gender, age, and years of education were included as covariates. In patients with subjective cognitive impairment, T-tau had a small impact on executive functions (r2 = 0.07). T-tau had a small to moderate influence (r2 = 0.06-0.11) on all cognitive functions with the exception of visuospatial functions in patients with mild cognitive impairment (MCI). In patients with dementia, the impact of T-tau was large (r2 = 0.29) on semantic memory. Aβ42 had a small effect (r2 = 0.07) on speed and executive functions in MCI. In patients with dementia, Aβ42 had a moderate influence (r2 = 0.13-0.24) on semantic and verbal working memory/fluency. Our results speak in favor of the notion that CSF biomarkers reflect the rate of cognitive decline across the continuum of cognitive impairment from healthy to dementia. CSF predicted subsequent decline in more cognitive domains among MCI cases, but the impact was most pronounced in patients with dementia.

  14. Are neonicotinoid insecticides driving declines of widespread butterflies?

    PubMed Central

    Bunnefeld, Nils; Wilson, John McVean; Botham, Marc S.; Brereton, Tom M.; Fox, Richard; Goulson, Dave

    2015-01-01

    There has been widespread concern that neonicotinoid pesticides may be adversely impacting wild and managed bees for some years, but recently attention has shifted to examining broader effects they may be having on biodiversity. For example in the Netherlands, declines in insectivorous birds are positively associated with levels of neonicotinoid pollution in surface water. In England, the total abundance of widespread butterfly species declined by 58% on farmed land between 2000 and 2009 despite both a doubling in conservation spending in the UK, and predictions that climate change should benefit most species. Here we build models of the UK population indices from 1985 to 2012 for 17 widespread butterfly species that commonly occur at farmland sites. Of the factors we tested, three correlated significantly with butterfly populations. Summer temperature and the index for a species the previous year are both positively associated with butterfly indices. By contrast, the number of hectares of farmland where neonicotinoid pesticides are used is negatively associated with butterfly indices. Indices for 15 of the 17 species show negative associations with neonicotinoid usage. The declines in butterflies have largely occurred in England, where neonicotinoid usage is at its highest. In Scotland, where neonicotinoid usage is comparatively low, butterfly numbers are stable. Further research is needed urgently to show whether there is a causal link between neonicotinoid usage and the decline of widespread butterflies or whether it simply represents a proxy for other environmental factors associated with intensive agriculture. PMID:26623186

  15. 24 CFR 200.23 - Projects in declining neighborhoods.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 24 Housing and Urban Development 2 2011-04-01 2011-04-01 false Projects in declining neighborhoods... HOUSING AND URBAN DEVELOPMENT GENERAL INTRODUCTION TO FHA PROGRAMS Requirements for Application... Programs; and Continuing Eligibility Requirements for Existing Projects Miscellaneous Project...

  16. 24 CFR 200.23 - Projects in declining neighborhoods.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Projects in declining neighborhoods... HOUSING AND URBAN DEVELOPMENT GENERAL INTRODUCTION TO FHA PROGRAMS Requirements for Application... Programs; and Continuing Eligibility Requirements for Existing Projects Miscellaneous Project...

  17. History Jobs Decline 15% after Years of Growth

    ERIC Educational Resources Information Center

    Wilson, Robin

    2009-01-01

    This article reports that a five-year stretch of steady growth in the job market for academic historians is over. The number of job advertisements colleges have posted with the American Historical Association so far this academic year is down 15 percent from last year--the first decline since a slump that occurred in 2001-2002 and 2002-2003. The…

  18. Fertility Decline in Rural China: A Comparative Analysis

    PubMed Central

    Harrell, Stevan; Yuesheng, Wang; Hua, Han; Santos, Gonçalo D.; Yingying, Zhou

    2014-01-01

    Many models have been proposed to explain both the rapidity of China’s fertility decline after the 1960s and the differential timing of the decline in different places. In particular, scholars argue over whether deliberate policies of fertility control, institutional changes, or general modernization factors contribute most to changes in fertility behavior. Here the authors adopt an ethnographically grounded behavioral–institutional approach to analyze qualitative and quantitative data from three different rural settings: Xiaoshan County in Zhejiang (East China), Ci County in Hebei (North China), and Yingde County in Guangdong (South China). The authors show that no one set of factors explains the differential timing and rapidity of the fertility decline in the three areas; rather they must explain differential timing by a combination of differences in social–cultural environments (e.g., spread of education, reproductive ideologies, and gender relations) and politico-economic conditions (e.g., economic development, birth planning campaigns, and collective systems of labor organization) during the early phases of the fertility decline. PMID:21319442

  19. Decadence, Scorn, and the Decline of Christian Practice on Campus

    ERIC Educational Resources Information Center

    French, David

    2010-01-01

    Religious practice dramatically decreases in college and students' positions on hot-button religious/cultural questions move appreciably to the left. There's no doubt that college students are on a quest for meaning. In this article, the author reports on new data that reveals unequivocally the decline of religious practice among college students.…

  20. Report of the Task Force on Declining Enrollment. Third Revision.

    ERIC Educational Resources Information Center

    Highline Public Schools, Seattle, WA.

    The purpose of this task force was to study the program, facilities, and alternatives of the Highline School District as they relate to enrollment decline. Specifically, the task force was to establish criteria for identifying facilities where changes should be considered; identify and prioritize alternatives for use of excess classroom space; and…

  1. What Should We Do about the Decline in Vocational Enrollment?

    ERIC Educational Resources Information Center

    Lonza, Martin

    Vocational enrollment is declining because of an increase in academic requirements. Because job skills are changing so rapidly, employers are increasingly choosing to provide their own vocational training to students who have mastered standard academic requirements. However, the lack of hands-on methodology in academic curricula and the lack of…

  2. Are neonicotinoid insecticides driving declines of widespread butterflies?

    PubMed

    Gilburn, Andre S; Bunnefeld, Nils; Wilson, John McVean; Botham, Marc S; Brereton, Tom M; Fox, Richard; Goulson, Dave

    2015-01-01

    There has been widespread concern that neonicotinoid pesticides may be adversely impacting wild and managed bees for some years, but recently attention has shifted to examining broader effects they may be having on biodiversity. For example in the Netherlands, declines in insectivorous birds are positively associated with levels of neonicotinoid pollution in surface water. In England, the total abundance of widespread butterfly species declined by 58% on farmed land between 2000 and 2009 despite both a doubling in conservation spending in the UK, and predictions that climate change should benefit most species. Here we build models of the UK population indices from 1985 to 2012 for 17 widespread butterfly species that commonly occur at farmland sites. Of the factors we tested, three correlated significantly with butterfly populations. Summer temperature and the index for a species the previous year are both positively associated with butterfly indices. By contrast, the number of hectares of farmland where neonicotinoid pesticides are used is negatively associated with butterfly indices. Indices for 15 of the 17 species show negative associations with neonicotinoid usage. The declines in butterflies have largely occurred in England, where neonicotinoid usage is at its highest. In Scotland, where neonicotinoid usage is comparatively low, butterfly numbers are stable. Further research is needed urgently to show whether there is a causal link between neonicotinoid usage and the decline of widespread butterflies or whether it simply represents a proxy for other environmental factors associated with intensive agriculture.

  3. The Unusual Behavior of TT Arietis: 2009 October Decline

    NASA Astrophysics Data System (ADS)

    Koff, Robert A.; Patterson, Joe

    This paper presents the results of the photometric study of TT Arietis during its decline phase of 2009 October, when the star exhibited very unexpected behavior. CBA observers and others provided time-series photometry to study the star and to complement the observations of the Swift and GALEX satellites.

  4. When Patients Decline Medical Student Participation: The Preceptors' Perspective

    ERIC Educational Resources Information Center

    Tang, Tricia S.; Skye, Eric P.

    2009-01-01

    Patients' receptivity towards medical student participation has been examined predominantly from the patient and/or the medical student perspective. Few studies have investigated the preceptor's perspective. The study examined preceptors' experience with patients declining medical student participation in clinical care and identified…

  5. Pesticides and Population Declines of California Alpine Frogs

    EPA Science Inventory

    Airborne pesticides from the Central Valley of California have been implicated as a cause for population declines of several amphibian species, with the strongest evidence for the mountain yellow-legged frog complex (Rana muscosa and R. sierrae) in the Sierra Nevada. We measured ...

  6. In a Decade of Decline: The Seven R's of Planning.

    ERIC Educational Resources Information Center

    Peterson, Marvin W.

    1984-01-01

    Administrators must focus on the long-term effects of resource decline and identify a strategy to promote renewal and prevent stagnation. Redefinition of mission, rethinking models, reintegration of organizational processes, revitalizing members, reparations, recuperation and repatriation, and recommitment are discussed. (MLW)

  7. President Hails Continued Decline in Default Rate on Student Loans.

    ERIC Educational Resources Information Center

    Burd, Stephen

    1997-01-01

    President Bill Clinton used the declining default rate on college student loans as a basis for proposing tax breaks for college costs. Reduced defaults have saved taxpayer money and helped reduce the federal deficit. Over 150 colleges and universities, including 25 private institutions, risk losing eligibility for federal grant and loan programs…

  8. Detecting insect pollinator declines on regional and global scales.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recently, there has been considerable concern about declines in pollinator populations in both agricultural and natural habitats. The value of pollination services to agriculture, primarily by bees, is conservatively estimated to exceed $200 billion U.S. annually and the value of pollination servic...

  9. Yes, we can! Detect pollinator declines on a global scale

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recently there has been considerable concern about declines in bee communities, both in agricultural and natural habitats. The value of pollination to agriculture, provided primarily by bees, is > $200 billion US annually, and in natural ecosystems is thought to be even greater. However, because n...

  10. The Assessment of Behavioural Decline in Adults with Down's Syndrome.

    ERIC Educational Resources Information Center

    McKenzie, Karen; Harte, Cyan; Patrick, Shona; Matheson, Edith; Murray, George C.

    2002-01-01

    A study examined two methods of using the Vineland Adaptive Behavior Scales with people with Down syndrome at risk of developing Alzheimer's disease. Scoring the scales using the basal rule outlined in the manual resulted in highlighting significant declines in scores for those meeting the criteria for "probable Alzheimer's disease."…

  11. Decline of recent seabirds inferred from a composite 1000-year record of population dynamics

    PubMed Central

    Xu, Liqiang; Liu, Xiaodong; Wu, Libin; Sun, Liguang; Zhao, Jinjun; Chen, Lin

    2016-01-01

    Based on three ornithogenic sediment profiles and seabird subfossils therein from the Xisha Islands, South China Sea, the relative population size of seabirds over the past 1000 years was reconstructed using reflectance spectrum. Here we present an apparent increase and subsequent decline of seabirds on these islands in the South China Sea. Seabird populations peaked during the Little Ice Age (LIA, 1400–1850 AD), implying that the cool climate during the LIA appears to have been more favorable to seabirds on the Xisha Islands in the South China Sea. Climate change partly explains the recent decrease in seabird populations over the past 150 years, but the significant decline and almost complete disappearance thereof on most of the Xisha Islands is probably attributable to human disturbance. Our study reveals the increasing impact of anthropogenic activities on seabird population in recent times. PMID:27748366

  12. Decline of recent seabirds inferred from a composite 1000-year record of population dynamics

    NASA Astrophysics Data System (ADS)

    Xu, Liqiang; Liu, Xiaodong; Wu, Libin; Sun, Liguang; Zhao, Jinjun; Chen, Lin

    2016-10-01

    Based on three ornithogenic sediment profiles and seabird subfossils therein from the Xisha Islands, South China Sea, the relative population size of seabirds over the past 1000 years was reconstructed using reflectance spectrum. Here we present an apparent increase and subsequent decline of seabirds on these islands in the South China Sea. Seabird populations peaked during the Little Ice Age (LIA, 1400–1850 AD), implying that the cool climate during the LIA appears to have been more favorable to seabirds on the Xisha Islands in the South China Sea. Climate change partly explains the recent decrease in seabird populations over the past 150 years, but the significant decline and almost complete disappearance thereof on most of the Xisha Islands is probably attributable to human disturbance. Our study reveals the increasing impact of anthropogenic activities on seabird population in recent times.

  13. Pesticides are involved with population declines of amphibians in the California Sierra Nevadas

    USGS Publications Warehouse

    Sparling, D.W.; Fellers, G.; McConnell, L.

    2001-01-01

    Several species of frogs and toads are in serious decline in the Sierra Nevada Mountains of California. These species include the threatened red-legged frog ( Rana aurora ), foothill yellow-legged frog ( R. boylii ), mountain yellow-legged frog ( R. muscosa ), Cascades frog ( Rana cascadae ), western toad ( Bufo boreas ) and Yosemite toad ( B. canorus ). For many of these species current distributions are down to 10% of historical ranges. Several factors including introduced predators, habitat loss, and ultraviolet radiation have been suggested as causes of these declines. Another probable cause is air-borne pesticides from the Central Valley of California. The Central Valley, especially the San Joaquin Valley, is a major agricultural region where millions of pounds of active ingredient pesticides are applied each year (http://www.cdpr.ca.gov/dprdatabase.htm). Prevailing westerly winds from the Pacific Coast transport these pesticides into the into the Sierras.

  14. IANA task force on nutrition and cognitive decline with aging.

    PubMed

    Gillette Guyonnet, S; Abellan Van Kan, G; Andrieu, S; Barberger Gateau, P; Berr, C; Bonnefoy, M; Dartigues, J F; de Groot, L; Ferry, M; Galan, P; Hercberg, S; Jeandel, C; Morris, M C; Nourhashemi, F; Payette, H; Poulain, J P; Portet, F; Roussel, A M; Ritz, P; Rolland, Y; Vellas, B

    2007-01-01

    Cognitive impairment can be influenced by a number of factors. The potential effect of nutrition has become a topic of increasing scientific and public interest. In particular, there are arguments that nutrients (food and/or supplements) such as vitamins, trace minerals, lipids, can affect the risk of cognitive decline and dementia, especially in frail elderly people at risk of deficiencies. Our objective in this paper is to review data relating diet to risk of cognitive decline and dementia, especially Alzheimer's disease (AD). We chose to focus our statements on homocysteine-related vitamins (B-vitamins), antioxidant nutrients (vitamins E and C, carotenoids, flavonoids, enzymatic cofactors) and dietary lipids. Results of epidemiological studies may sometimes appeared conflicting; however, certain associations are frequently found. High intake of saturated and trans-unsaturated (hydrogenated) fats were positively associated with increased risk of AD, whereas intake of polyunsaturated and monounsaturated fats were protective against cognitive decline in the elderly in prospective studies. Fish consumption has been associated with lower risk of AD in longitudinal cohort studies. Moreover, epidemiologic data suggest a protective role of the B-vitamins, especially vitamins B9 and B12, on cognitive decline and dementia. Finally, the results on antioxidant nutrients may suggest the importance of having a balanced combination of several antioxidant nutrients to exert a significant effect on the prevention of cognitive decline and dementia, while taking into account the potential adverse effects of these nutrients. There is no lack of attractive hypotheses to support research on the relationships between nutrition and cognitive decline. It is important to stress the need to develop further prospective studies of sufficiently long duration, including subjects whose diet is monitored at a sufficiently early stage or at least before disease or cognitive decline exist. Meta

  15. Down-shifting among top UK scientists? - the decline of 'revolutionary science' and the rise of 'normal science' in the UK compared with the USA.

    PubMed

    Charlton, Bruce G; Andras, Peter

    2008-01-01

    It is sometimes asserted that UK science is thriving, at other times that it has declined. We suggest that both assertions are partly true because the UK is thriving with respect to the volume of 'normal' science production but at the same time declining in the highest level of 'revolutionary' science. Revolutionary science may be distinguished from normal science in that revolutionary science aims at generating qualitative advances which change the direction of established science, while 'normal' science aims at incremental progress extrapolating from established science. Revolutionary science has been measured by counting national numbers of science Nobel laureates and ISI Highly Cited (HiCi) scientists; normal science has been measured using the total volume of scientific publications and citations at both national and institutional levels. By these criteria the UK has been progressively catching-up with the USA in terms of normal science since the 1990s. At the same time the UK has declined in revolutionary science over recent decades by a significant brain drain of future Nobel laureates and HiCi scientists, and a sharply reduced success (both in absolute and compared with the USA) at winning science Nobel prizes. One possible cause for this pattern could be a time-lag, such that the UK's improved science production since about 1990 may eventually work-through into improved UK performance in revolutionary science. More pessimistically, this pattern may reflect a strategic down-shift of the best UK-resident scientists away from revolutionary science and towards less-ambitious and safer normal science which is more productive in the short term.

  16. Dietary patterns, cognitive decline, and dementia: a systematic review.

    PubMed

    van de Rest, Ondine; Berendsen, Agnes Am; Haveman-Nies, Annemien; de Groot, Lisette Cpgm

    2015-03-01

    Nutrition is an important modifiable risk factor that plays a role in the strategy to prevent or delay the onset of dementia. Research on nutritional effects has until now mainly focused on the role of individual nutrients and bioactive components. However, the evidence for combined effects, such as multinutrient approaches, or a healthy dietary pattern, such as the Mediterranean diet, is growing. These approaches incorporate the complexity of the diet and possible interaction and synergy between nutrients. Over the past few years, dietary patterns have increasingly been investigated to better understand the link between diet, cognitive decline, and dementia. In this systematic review we provide an overview of the literature on human studies up to May 2014 that examined the role of dietary patterns (derived both a priori as well as a posteriori) in relation to cognitive decline or dementia. The results suggest that better adherence to a Mediterranean diet is associated with less cognitive decline, dementia, or Alzheimer disease, as shown by 4 of 6 cross-sectional studies, 6 of 12 longitudinal studies, 1 trial, and 3 meta-analyses. Other healthy dietary patterns, derived both a priori (e.g., Healthy Diet Indicator, Healthy Eating Index, and Program National Nutrition Santé guideline score) and a posteriori (e.g., factor analysis, cluster analysis, and reduced rank regression), were shown to be associated with reduced cognitive decline and/or a reduced risk of dementia as shown by all 6 cross-sectional studies and 6 of 8 longitudinal studies. More conclusive evidence is needed to reach more targeted and detailed guidelines to prevent or postpone cognitive decline.

  17. Subtle Cognitive Decline and Biomarker Staging in Preclinical Alzheimer's Disease.

    PubMed

    Edmonds, Emily C; Delano-Wood, Lisa; Galasko, Douglas R; Salmon, David P; Bondi, Mark W

    2015-01-01

    The NIA-AA criteria for "preclinical" Alzheimer's disease (AD) propose a staging method in which AD biomarkers follow an invariable temporal sequence in accordance with the amyloid cascade hypothesis. However, recent findings do not align with the proposed temporal sequence and "subtle cognitive decline," which has not been definitively operationalized, may occur earlier than suggested in preclinical AD. We aimed to define "subtle cognitive decline" using sensitive and reliable neuropsychological tests, and to examine the number and sequence of biomarker abnormalities in the Alzheimer's Disease Neuroimaging Initiative (ADNI). 570 cognitively normal ADNI participants were classified based on NIA-AA criteria and separately based on the number of abnormal biomarkers/cognitive markers associated with preclinical AD that each individual possessed. Results revealed that neurodegeneration alone was 2.5 times more common than amyloidosis alone at baseline. For those who demonstrated only one abnormal biomarker at baseline and later progressed to mild cognitive impairment/AD, neurodegeneration alone was most common, followed by amyloidosis alone or subtle cognitive decline alone, which were equally common. Findings suggest that most individuals do not follow the temporal order proposed by NIA-AA criteria. We provide an operational definition of subtle cognitive decline that captures both cognitive and functional decline. Additionally, we offer a new approach for staging preclinical AD based on number of abnormal biomarkers, without regard to their temporal order of occurrence. This method of characterizing preclinical AD is more parsimonious than the NIA-AA staging system and does not presume that all patients follow a singular invariant expression of the disease.

  18. Evaluating the links between climate, disease spread, and amphibian declines.

    PubMed

    Rohr, Jason R; Raffel, Thomas R; Romansic, John M; McCallum, Hamish; Hudson, Peter J

    2008-11-11

    Human alteration of the environment has arguably propelled the Earth into its sixth mass extinction event and amphibians, the most threatened of all vertebrate taxa, are at the forefront. Many of the worldwide amphibian declines have been caused by the chytrid fungus, Batrachochytrium dendrobatidis (Bd), and two contrasting hypotheses have been proposed to explain these declines. Positive correlations between global warming and Bd-related declines sparked the chytrid-thermal-optimum hypothesis, which proposes that global warming increased cloud cover in warm years that drove the convergence of daytime and nighttime temperatures toward the thermal optimum for Bd growth. In contrast, the spatiotemporal-spread hypothesis states that Bd-related declines are caused by the introduction and spread of Bd, independent of climate change. We provide a rigorous test of these hypotheses by evaluating (i) whether cloud cover, temperature convergence, and predicted temperature-dependent Bd growth are significant positive predictors of amphibian extinctions in the genus Atelopus and (ii) whether spatial structure in the timing of these extinctions can be detected without making assumptions about the location, timing, or number of Bd emergences. We show that there is spatial structure to the timing of Atelopus spp. extinctions but that the cause of this structure remains equivocal, emphasizing the need for further molecular characterization of Bd. We also show that the reported positive multi-decade correlation between Atelopus spp. extinctions and mean tropical air temperature in the previous year is indeed robust, but the evidence that it is causal is weak because numerous other variables, including regional banana and beer production, were better predictors of these extinctions. Finally, almost all of our findings were opposite to the predictions of the chytrid-thermal-optimum hypothesis. Although climate change is likely to play an important role in worldwide amphibian declines

  19. Specifically neuropathic Gaucher's mutations accelerate cognitive decline in Parkinson's

    PubMed Central

    Liu, Ganqiang; Boot, Brendon; Locascio, Joseph J.; Jansen, Iris E.; Winder‐Rhodes, Sophie; Eberly, Shirley; Elbaz, Alexis; Brice, Alexis; Ravina, Bernard; van Hilten, Jacobus J.; Cormier‐Dequaire, Florence; Corvol, Jean‐Christophe; Barker, Roger A.; Heutink, Peter; Marinus, Johan; Williams‐Gray, Caroline H.; Scherzer, C.; Hyman, B.T.; Ivinson, A.J.; Trisini‐Lipsanopoulos, A.; Franco, D.; Burke, K.; Sudarsky, L.R.; Hayes, M.T.; Umeh, C.C.; Growdon, J.H.; Schwarzschild, M.A.; Hung, A.Y.; Flaherty, A.W.; Wills, A.‐M.; Mejia, N.I.; Gomperts, S.N.; Khurana, V.; Selkoe, D.J.; Yi, T.; Page, K.; Liao, Z.; Barker, R.; Foltynie, T.; Williams‐Gray, C.H.; Mason, S.; Winder‐Rhodes, S.; Barker, R.; Williams‐Gray, C.H.; Breen, D.; Cummins, G.; Evans, J.; Winder‐Rhodes, S.; Corvol, J.‐C.; Brice, A.; Elbaz, A.; Mallet, A.; Vidailhet, M.; Bonnet, A.‐M.; Bonnet, C.; Grabli, D.; Hartmann, A.; Klebe, S.; Lacomblez, L.; Mangone, G.; Bourdain, F.; Brandel, J.‐P.; Derkinderen, P.; Durif, F.; Mesnage, V.; Pico, F.; Rascol, O.; Forlani, S.; Lesage, S.; Tahiri, K.; van Hilten, J.J.; Marinus, J.; Liao, Z.; Page, K.; Franco, D.; Duong, K.; Yi, T.; Trisini‐Lipsanopoulos, A.; Dong, X.; Sudarsky, L.R.; Hutten, S.J.; Amr, S.S.; Shoulson, I.; Tanner, C.M.; Lang, A.E.; Nalls, M.A.

    2016-01-01

    Objective We hypothesized that specific mutations in the β‐glucocerebrosidase gene (GBA) causing neuropathic Gaucher's disease (GD) in homozygotes lead to aggressive cognitive decline in heterozygous Parkinson's disease (PD) patients, whereas non‐neuropathic GD mutations confer intermediate progression rates. Methods A total of 2,304 patients with PD and 20,868 longitudinal visits for up to 12.8 years (median, 4.1) from seven cohorts were analyzed. Differential effects of four types of genetic variation in GBA on longitudinal cognitive decline were evaluated using mixed random and fixed effects and Cox proportional hazards models. Results Overall, 10.3% of patients with PD and GBA sequencing carried a mutation. Carriers of neuropathic GD mutations (1.4% of patients) had hazard ratios (HRs) for global cognitive impairment of 3.17 (95% confidence interval [CI], 1.60–6.25) and a hastened decline in Mini–Mental State Exam scores compared to noncarriers (p = 0.0009). Carriers of complex GBA alleles (0.7%) had an HR of 3.22 (95% CI, 1.18–8.73; p = 0.022). By contrast, the common, non‐neuropathic N370S mutation (1.5% of patients; HR, 1.96; 95% CI, 0.92–4.18) or nonpathogenic risk variants (6.6% of patients; HR, 1.36; 95% CI, 0.89–2.05) did not reach significance. Interpretation Mutations in the GBA gene pathogenic for neuropathic GD and complex alleles shift longitudinal cognitive decline in PD into “high gear.” These findings suggest a relationship between specific types of GBA mutations and aggressive cognitive decline and have direct implications for improving the design of clinical trials. Ann Neurol 2016;80:674–685 PMID:27717005

  20. Declines in Sexual Frequency among American Adults, 1989-2014.

    PubMed

    Twenge, Jean M; Sherman, Ryne A; Wells, Brooke E

    2017-03-06

    American adults had sex about nine fewer times per year in the early 2010s compared to the late 1990s in data from the nationally representative General Social Survey, N = 26,620, 1989-2014. This was partially due to the higher percentage of unpartnered individuals, who have sex less frequently on average. Sexual frequency declined among the partnered (married or living together) but stayed steady among the unpartnered, reducing the marital/partnered advantage for sexual frequency. Declines in sexual frequency were similar across gender, race, region, educational level, and work status and were largest among those in their 50s, those with school-age children, and those who did not watch pornography. In analyses separating the effects of age, time period, and cohort, the decline was primarily due to birth cohort (year of birth, also known as generation). With age and time period controlled, those born in the 1930s (Silent generation) had sex the most often, whereas those born in the 1990s (Millennials and iGen) had sex the least often. The decline was not linked to longer working hours or increased pornography use. Age had a strong effect on sexual frequency: Americans in their 20s had sex an average of about 80 times per year, compared to about 20 times per year for those in their 60s. The results suggest that Americans are having sex less frequently due to two primary factors: An increasing number of individuals without a steady or marital partner and a decline in sexual frequency among those with partners.

  1. Almagest Declinations: Ptolemy or “As found by us”

    NASA Astrophysics Data System (ADS)

    Brandt, John C.; Zimmer, P. C.; Jones, P. B.

    2013-01-01

    Consistent results and compatibility with historical evidence were reported by Zimmer, Brandt, and Jones for Almagest declinations determined by Timocharis, Aristyllus, and Hipparcus. Unfortunately, this situation does not apply to the Almagest declinations (Book VII, Chapter 3; Toomer 1998) for Ptolemy or “As found by us.” Our formal solution gives a precision of 11.9 arc min and an epoch near 115AD. The precision is significantly worse than for the earlier observers and the date conflicts with historical data. Inspection of the (O) - (C) plots vs. year reveals that the natural clustering of trajectories seen for the other observers is not seen for the Ptolemy declinations. In addition, the spread in dates of observations estimated from the times of (O) - (C) = 0 shows a much larger value for Ptolemy than for the others. Historically, the Almagest was published around 150AD or perhaps a little later. Ptolemy’s life span was likely from c.100AD to c.175AD. Thus, the 115AD date for his observations is much too early. Maeyama (1984) moved the epoch from 115AD to 137/138AD by dropping stars from the analysis. Rawlins (manuscript, c. 1983) has an extensive discussion, drops several stars, and finds a preferred epoch of 137AD. He regards the observer as unknown. We prefer not to drop stars from the analysis unless the evidence is overwhelming. Our solution is to take Ptolemy literally. In Toomer (1998; tables on pages 331 & 332), these declinations are “As found by us” and in Taliaferro (1952; in the text) are as “we find it.” The idea of multiple observers has been suggested before and our analysis certainly supports the declinations coming from multiple observers through the years.

  2. [Effect of different organic fraction on membrane flux declines].

    PubMed

    Zhou, Xian-Jiao; Dong, Bing-Zhi

    2009-02-15

    Organic matter in the tap water was isolated into strongly hydrophobic acids, weakly hydrophobic acids, charged hydrophilic and neutral hydrophilic by DAX-8, XAD-4 and IRA-958 synthetic resins. Filtration tests using polyvinylidene fluoride (PVDF), polyethersulphone (PES) and cellulose acetate (CA) membranes were conducted to investigate the contribution of different organic fractions to membrane fouling. The results show that in filtration of raw water, flux declines with PES, PVDF and CA membrane are 67%, 59% and 19% of the initial flux, indicating that the more hydrophobic membrane resulted in more severe fouling. For the effect of different fractions on flux, flux decline with neutral hydrophilic is 41%-75% of the initial flux, whereas weakly hydrophobic acids is 6%-33%, suggesting that neutral hydrophilic has a great impact on filtration flux. Among three membranes tested, CA membrane shows the lowest flux decline compared with other membranes in spite of rejection of as high as 14.69% of neutral hydrophilic, suggesting that the extent of flux decline may not be associated with the total amount of NOM removed. The mechanism of fouling was discussed and found that the neutral hydrophilic fraction with greater than 3 x 10(4) of molecular weight caused a significant flux decline, through blocking the pore for the MF or UF having greater relative molecular mass cut-off (MWCO), but resulted in a little impact on flux with the UF having lower MWCO, through forming cake layer on the surface of membrane due to not entering the inside of pore.

  3. Dietary Patterns, Cognitive Decline, and Dementia: A Systematic Review12

    PubMed Central

    van de Rest, Ondine; Berendsen, Agnes AM; Haveman-Nies, Annemien; de Groot, Lisette CPGM

    2015-01-01

    Nutrition is an important modifiable risk factor that plays a role in the strategy to prevent or delay the onset of dementia. Research on nutritional effects has until now mainly focused on the role of individual nutrients and bioactive components. However, the evidence for combined effects, such as multinutrient approaches, or a healthy dietary pattern, such as the Mediterranean diet, is growing. These approaches incorporate the complexity of the diet and possible interaction and synergy between nutrients. Over the past few years, dietary patterns have increasingly been investigated to better understand the link between diet, cognitive decline, and dementia. In this systematic review we provide an overview of the literature on human studies up to May 2014 that examined the role of dietary patterns (derived both a priori as well as a posteriori) in relation to cognitive decline or dementia. The results suggest that better adherence to a Mediterranean diet is associated with less cognitive decline, dementia, or Alzheimer disease, as shown by 4 of 6 cross-sectional studies, 6 of 12 longitudinal studies, 1 trial, and 3 meta-analyses. Other healthy dietary patterns, derived both a priori (e.g., Healthy Diet Indicator, Healthy Eating Index, and Program National Nutrition Santé guideline score) and a posteriori (e.g., factor analysis, cluster analysis, and reduced rank regression), were shown to be associated with reduced cognitive decline and/or a reduced risk of dementia as shown by all 6 cross-sectional studies and 6 of 8 longitudinal studies. More conclusive evidence is needed to reach more targeted and detailed guidelines to prevent or postpone cognitive decline. PMID:25770254

  4. Distribution system in Bangladesh spurs decline in growth.

    PubMed

    1992-01-01

    Fertility reductions in Bangladesh have contributed to a reduction in population growth from 2.5% between 1981 and 1991 to 2.3% in 1991. The average density of 800 persons/sq. km means competition for resources in a subsistence level economy. There is scarcity of land, food shortages, and an abundance of labor. Rapid socioeconomic development is not possible even with an average annual economic growth rate of 3.7% because of population growth. Birth control has doubled to 18.6% in 1991. Sterilization is no longer the primary means of contraception. Contraceptive usage increases are more widespread among young women who are spacing births. A recent study reports that fertility declines are due to increases in the expansion of family planning field workers over the past decade. Home distribution is considered compatible with sociocultural traditions. In 1990, there was 1 field worker/856 married women of reproductive age. 120 private voluntary organizations and the government provide contraceptive services. In 1989, 40% of pill and condom users obtained their supplies from commercial channels. This is possible because of the successful social marketing available through 130,000 commercial retail outlets. Nongovernmental organizations have also been given the freedom to operate independently from government programs. The International Center for Diarrheal Disease Research contributed to the contraceptive effort by field testing in Matlab, Aboynagar, and Sirajganj the introduction of door-to-door injectable contraception services and the building of satellite clinics. The information, education, and communications (IEC) activities also contributed to the 95.4% of women knowledgeable about at least 4 methods of contraception. Kantner and Noor reported that 14.4 million births were averted due to an increase in marriage age (from 16.3 years in 1974) to (17.7 years in 1989). Program efforts are being accelerated because of the 45% of the population that is presently under

  5. Immunological predictors of CD4+ T cell decline in antiretroviral treatment interruptions

    PubMed Central

    Seoane, Elena; Resino, Salvador; Moreno, Santiago; de Quiros, Juan Carlos Lopez Bernaldo; Moreno, Ana; Rubio, Rafael; Gonzalez-García, Juan; Arribas, José Ramón; Pulido, Federico; Muñoz-Fernández, Ma Ángeles

    2008-01-01

    Background The common response to stopping anti-HIV treatment is an increase of HIV-RNA load and decrease in CD4+, but not all the patients have similar responses to this therapeutic strategy. The aim was to identify predictive markers of CD4+ cell count declines to < 350/μL in CD4-guided antiretroviral treatment interruptions. Methods 27 HIV-infected patients participated in a prospective multicenter study in with a 24 month follow-up. Patients on stable highly active antiretroviral therapy (HAART), with CD4+ count > 600/μL, and HIV-RNA < 50 copies/ml for at least 6 months were offered the option to discontinue antiretroviral therapy. The main outcome was a decline in CD4+ cell count to < 350/μL. Results After 24 months of follow-up, 16 of 27 (59%) patients (who discontinued therapy) experienced declines in CD4+ cell count to < 350/μL. Patients with a CD4+ nadir of < 200 cells/μL had a greater risk of restarting therapy during the follow-up (RR (CI95%): 3.37 (1.07; 10.36)). Interestingly, lymphoproliferative responses to Mycobacterium tuberculosis purified protein derivative (PPD) below 10000 c.p.m. at baseline (4.77 (1.07; 21.12)), IL-4 production above 100 pg/mL at baseline (5.95 (1.76; 20.07)) in PBMC cultured with PPD, and increased IL-4 production of PBMC with p24 antigen at baseline (1.25 (1.01; 1.55)) were associated to declines in CD4+ cell count to < 350/μL. Conclusion Both the number (CD4+ nadir) and the functional activity of CD4+ (lymphoproliferative response to PPD) predict the CD4+ decrease associated with discontinuation of ART in patients with controlled viremia. PMID:18302775

  6. Has contemporary climate change played a role in population declines of the lizard Ctenophorus decresii from semi-arid Australia?

    PubMed

    Walker, Samantha; Stuart-Fox, Devi; Kearney, Michael R

    2015-12-01

    Whilst contemporary climatic changes are small in magnitude compared to those predicted for the coming decades, they have already been linked to species range shifts and local extinctions. Elucidating the drivers behind species' responses to contemporary climate change will better inform management strategies for vulnerable and pest species alike. A recent proposal to explain worldwide local extinctions in lizards is that increasing maximum temperatures have constrained lizard activity time in the breeding season beyond extinction thresholds. Here we document a significant population decline and potential local extinction at the warm (northern) range margin of the tawny dragon, Ctenophorus decresii, a rock-dwelling lizard from the Flinders Ranges in semi-arid Australia. We developed and tested a biophysical model of tawny dragon thermoregulatory behaviour and drove the model with daily weather data for the period 1990-2009 across the Flinders Ranges. Our results indicate that potential annual activity time has likely increased over this period throughout the historic range, with within-season declines only in the summer months at the northern range limit. However, populations that have declined since 2000 have also likely experienced higher active body temperatures and more stringent retreat-site requirements (deeper crevices) than have regions where the species remains common, during a period of declining rainfall. Our laboratory estimates of thermal preference in this species were insensitive to altered nutritional and hydric state. Thus it is possible that recent population declines are linked to desiccation stress driven by higher body temperatures and declining rainfall. Our study illustrates that simple indices of the impact of climate warming on animals, such as activity restriction, may in fact reflect a variety of potential mechanisms whose ultimate outcome will be contingent on other factors such as water and shelter availability.

  7. Is the Test Score Decline Responsible for the Productivity Growth Decline? Working Paper No. 87-05.

    ERIC Educational Resources Information Center

    Bishop, John

    This paper presents evidence that recent aptitude test score decline is signaling a significant deterioration in the quality of entering cohorts of workers. The impact of general intellectual achievement (GIA) on productivity; trends in the GIA of the adult populations, students, and working adults; accounting for the labor quality growth when…

  8. Multiple stressor effects in relation to declining amphibian populations

    USGS Publications Warehouse

    2003-01-01

    This book represents the work of several authors who participated in the symposium entitled 'Multiple Stressor Effects in Relation to Declining Amphibian Populations' convened 16-17 April, 2002, in Pittsburgh, Pennsylvania. Declines of amphibian populations of varying severity have been observed for many years, and in the last 8 to 10 years considerable progress has been made in documenting the status and distribution of a range of amphibian species. Habitat alteration and destruction are likely linked to many amphibian declines, but a variety of other factors, both anthropogenic and natural, have been observed or proposed to have caused declines or extinctions of amphibian populations. Unfortunately, determining the environmental causes for the decline of many species has proven difficult. The goals of this symposium were three-fold. First, highlight ASTM's historic role in providing a forum for the standardization of amphibian toxicity test methods and the characterization of adverse effects potentially associated with chemical stressors. Second, demonstrate through case studies the current state of technical 'tools' available to biologists, ecologists, environmental scientists and natural resource professionals for assessing amphibian populations exposed to various environmental stressors. And third, characterize a process that brings a range of interdisciplinary technical and management tools to the tasks of causal analysis, especially as those relate to a multiple stressor risk assessment 'mind-set.' As part of the symposium, scientists and resource management professionals from diverse fields including ecotoxicology and chemistry, ecology and field biology, conservation biology, and natural resource management and policy contributed oral presentations and posters that addressed topics related to declining amphibian populations and the role that various stressors have in those losses. The papers contained in this publication reflect the commitment of ASTM

  9. Medication Use and Functional Status Decline in Older Adults: A Narrative Review

    PubMed Central

    Peron, Emily P.; Gray, Shelly L.; Hanlon, Joseph T.

    2012-01-01

    OBJECTIVE To critically review published articles that have examined the relationship between medication use and functional status decline in the elderly. METHODS The MEDLINE and EMBASE databases were searched for English-language articles published from January 1986 to December 2010. Search terms included aged, humans, drug utilization, polypharmacy, inappropriate prescribing, anticholinergics, psychotropics, antihypertensives, drug burden index, functional status, function change or decline, activities of daily living, gait, mobility limitation, and disability. A manual search of the reference lists of the identified articles and the authors’ article files, book chapters, and recent reviews was conducted to retrieve additional publications. Only articles that used rigorous observational or interventional designs were included. Cross-sectional studies and case series were excluded from this review. RESULTS Nineteenstudies met the inclusion criteria. Five studies addressed the impact of suboptimal prescribing on function, three of which found an increased risk of worse function in community-dwelling subjects receiving polypharmacy. Three of the four studies that assessed benzodiazepine use and functional status decline found a statistically significant association. One cohort study identified no relationship between antidepressant use and functional status while a randomized trial found that amitriptyline, but not desipramine or paroxetine, impaired certain measures of gait. Two studies found that increasing anticholinergic burden was associated with worse functional status. In a study of hospitalized rehabilitation patients, users of hypnotics/anxiolytics (e.g., phenobarbital, zolpidem) had lower relative Functional Independence Measure motor gains than nonusers. Use of multiple central nervous system (CNS) drugs (using different definitions) was linked to greater declines in self-reported mobility and Short Physical Performance Battery (SPPB) scores in two

  10. Use of the Internet as a prevention tool against cognitive decline in normal aging

    PubMed Central

    Klimova, Blanka

    2016-01-01

    Recent demographic trends indicate that older people appear to be one of the fastest growing population groups worldwide. In the year 2000, people older than 65 years represented 12.4% of the population. This number is expected to rise to 19% by 2030, particularly in developed countries. Therefore, there is sustained effort at both national and international levels to prolong the active life of these people as long as possible. Since the present older generation at the age of 55 years is already digitally literate, the use of technologies is one of the solutions. The purpose of this study is to discuss the role of the Internet in the prevention of cognitive decline in normal aging. The author examines clinical studies that exploit the use of the Internet, including online training programs, in the prevention of cognitive decline in healthy older individuals. The findings of the clinical studies indicate that the use of the Internet, especially online cognitive training programs, may have a positive effect on the improvement of cognitive functions in healthy older adults. Nevertheless, larger sample longitudinal randomized controlled clinical trials aimed at the prevention of cognitive decline among healthy older adults are needed. PMID:27672317

  11. Age-related decline in motor behavior and striatal dopamine transporter in cynomolgus monkeys.

    PubMed

    Yue, Feng; Zeng, Sien; Wu, Di; Yi, Deqiao; Alex Zhang, Y; Chan, Piu

    2012-08-01

    Advanced human aging is associated with progressive declines of motor function and a risk factor for Parkinson's disease, which mainly involves central nigrostriatal dopaminergic system. The present study investigated age-related changes in motor behaviors and alterations of the number of nigrostriatal dopaminergic terminals in non-human primates. A total of 30 cynomolgus monkeys (Macaca fascicularis) of age 3.5-15.5 years were studied. Motor behaviors including upper limb movement time and the amount of overall home cage activity were quantitatively assessed using a modified movement assessment panel and a newly developed webcam-based monitoring system. The function of the dopaminergic system was semi-quantitatively measured by (99m)Tc-TRODAT-1 uptake rates, a dopamine transporter (DAT) specific radiopharmaceutical with SPECT imaging. The results showed a significant decline in motor behaviors associated with aging which were significantly correlated with age-related decreases of (99m)Tc-TRODAT-1 uptake. A further partial correlation analysis independent of age indicated that age contributed to the relationship between striatal DAT levels and motor behaviors. Our results indicate that normal aging-related dopamine physiology influences certain aspects of motor behaviors and suggest that aging-associated dysfunction in the nigrostriatal dopaminergic system may be an important factor contributing to the decline of motor behaviors in aging cynomolgus monkeys.

  12. Coin hoards speak of population declines in Ancient Rome.

    PubMed

    Turchin, Peter; Scheidel, Walter

    2009-10-13

    In times of violence, people tend to hide their valuables, which are later recovered unless the owners had been killed or driven away. Thus, the temporal distribution of unrecovered coin hoards is an excellent proxy for the intensity of internal warfare. We use this relationship to resolve a long-standing controversy in Roman history. Depending on who was counted in the early Imperial censuses (adult males or the entire citizenry including women and minors), the Roman citizen population of Italy either declined, or more than doubled, during the first century BCE. This period was characterized by a series of civil wars, and historical evidence indicates that high levels of sociopolitical instability are associated with demographic contractions. We fitted a simple model quantifying the effect of instability (proxied by hoard frequency) on population dynamics to the data before 100 BCE. The model predicts declining population after 100 BCE. This suggests that the vigorous growth scenario is highly implausible.

  13. Devastating Decline of Forest Elephants in Central Africa

    PubMed Central

    Blake, Stephen; Wittemyer, George; Hart, John; Williamson, Elizabeth A.; Aba’a, Rostand; Abitsi, Gaspard; Ambahe, Ruffin D.; Amsini, Fidèl; Bakabana, Parfait C.; Hicks, Thurston Cleveland; Bayogo, Rosine E.; Bechem, Martha; Beyers, Rene L.; Bezangoye, Anicet N.; Boundja, Patrick; Bout, Nicolas; Akou, Marc Ella; Bene, Lambert Bene; Fosso, Bernard; Greengrass, Elizabeth; Grossmann, Falk; Ikamba-Nkulu, Clement; Ilambu, Omari; Inogwabini, Bila-Isia; Iyenguet, Fortune; Kiminou, Franck; Kokangoye, Max; Kujirakwinja, Deo; Latour, Stephanie; Liengola, Innocent; Mackaya, Quevain; Madidi, Jacob; Madzoke, Bola; Makoumbou, Calixte; Malanda, Guy-Aimé; Malonga, Richard; Mbani, Olivier; Mbendzo, Valentin A.; Ambassa, Edgar; Ekinde, Albert; Mihindou, Yves; Morgan, Bethan J.; Motsaba, Prosper; Moukala, Gabin; Mounguengui, Anselme; Mowawa, Brice S.; Ndzai, Christian; Nixon, Stuart; Nkumu, Pele; Nzolani, Fabian; Pintea, Lilian; Plumptre, Andrew; Rainey, Hugo; de Semboli, Bruno Bokoto; Serckx, Adeline; Stokes, Emma; Turkalo, Andrea; Vanleeuwe, Hilde; Vosper, Ashley; Warren, Ymke

    2013-01-01

    African forest elephants– taxonomically and functionally unique–are being poached at accelerating rates, but we lack range-wide information on the repercussions. Analysis of the largest survey dataset ever assembled for forest elephants (80 foot-surveys; covering 13,000 km; 91,600 person-days of fieldwork) revealed that population size declined by ca. 62% between 2002–2011, and the taxon lost 30% of its geographical range. The population is now less than 10% of its potential size, occupying less than 25% of its potential range. High human population density, hunting intensity, absence of law enforcement, poor governance, and proximity to expanding infrastructure are the strongest predictors of decline. To save the remaining African forest elephants, illegal poaching for ivory and encroachment into core elephant habitat must be stopped. In addition, the international demand for ivory, which fuels illegal trade, must be dramatically reduced. PMID:23469289

  14. Devastating decline of forest elephants in central Africa.

    PubMed

    Maisels, Fiona; Strindberg, Samantha; Blake, Stephen; Wittemyer, George; Hart, John; Williamson, Elizabeth A; Aba'a, Rostand; Abitsi, Gaspard; Ambahe, Ruffin D; Amsini, Fidèl; Bakabana, Parfait C; Hicks, Thurston Cleveland; Bayogo, Rosine E; Bechem, Martha; Beyers, Rene L; Bezangoye, Anicet N; Boundja, Patrick; Bout, Nicolas; Akou, Marc Ella; Bene, Lambert Bene; Fosso, Bernard; Greengrass, Elizabeth; Grossmann, Falk; Ikamba-Nkulu, Clement; Ilambu, Omari; Inogwabini, Bila-Isia; Iyenguet, Fortune; Kiminou, Franck; Kokangoye, Max; Kujirakwinja, Deo; Latour, Stephanie; Liengola, Innocent; Mackaya, Quevain; Madidi, Jacob; Madzoke, Bola; Makoumbou, Calixte; Malanda, Guy-Aimé; Malonga, Richard; Mbani, Olivier; Mbendzo, Valentin A; Ambassa, Edgar; Ekinde, Albert; Mihindou, Yves; Morgan, Bethan J; Motsaba, Prosper; Moukala, Gabin; Mounguengui, Anselme; Mowawa, Brice S; Ndzai, Christian; Nixon, Stuart; Nkumu, Pele; Nzolani, Fabian; Pintea, Lilian; Plumptre, Andrew; Rainey, Hugo; de Semboli, Bruno Bokoto; Serckx, Adeline; Stokes, Emma; Turkalo, Andrea; Vanleeuwe, Hilde; Vosper, Ashley; Warren, Ymke

    2013-01-01

    African forest elephants- taxonomically and functionally unique-are being poached at accelerating rates, but we lack range-wide information on the repercussions. Analysis of the largest survey dataset ever assembled for forest elephants (80 foot-surveys; covering 13,000 km; 91,600 person-days of fieldwork) revealed that population size declined by ca. 62% between 2002-2011, and the taxon lost 30% of its geographical range. The population is now less than 10% of its potential size, occupying less than 25% of its potential range. High human population density, hunting intensity, absence of law enforcement, poor governance, and proximity to expanding infrastructure are the strongest predictors of decline. To save the remaining African forest elephants, illegal poaching for ivory and encroachment into core elephant habitat must be stopped. In addition, the international demand for ivory, which fuels illegal trade, must be dramatically reduced.

  15. Habitat split and the global decline of amphibians.

    PubMed

    Becker, Carlos Guilherme; Fonseca, Carlos Roberto; Haddad, Célio Fernando Baptista; Batista, Rômulo Fernandes; Prado, Paulo Inácio

    2007-12-14

    The worldwide decline in amphibians has been attributed to several causes, especially habitat loss and disease. We identified a further factor, namely "habitat split"-defined as human-induced disconnection between habitats used by different life history stages of a species-which forces forest-associated amphibians with aquatic larvae to make risky breeding migrations between suitable aquatic and terrestrial habitats. In the Brazilian Atlantic Forest, we found that habitat split negatively affects the richness of species with aquatic larvae but not the richness of species with terrestrial development (the latter can complete their life cycle inside forest remnants). This mechanism helps to explain why species with aquatic larvae have the highest incidence of population decline. These findings reinforce the need for the conservation and restoration of riparian vegetation.

  16. Coin hoards speak of population declines in Ancient Rome

    PubMed Central

    Turchin, Peter; Scheidel, Walter

    2009-01-01

    In times of violence, people tend to hide their valuables, which are later recovered unless the owners had been killed or driven away. Thus, the temporal distribution of unrecovered coin hoards is an excellent proxy for the intensity of internal warfare. We use this relationship to resolve a long-standing controversy in Roman history. Depending on who was counted in the early Imperial censuses (adult males or the entire citizenry including women and minors), the Roman citizen population of Italy either declined, or more than doubled, during the first century BCE. This period was characterized by a series of civil wars, and historical evidence indicates that high levels of sociopolitical instability are associated with demographic contractions. We fitted a simple model quantifying the effect of instability (proxied by hoard frequency) on population dynamics to the data before 100 BCE. The model predicts declining population after 100 BCE. This suggests that the vigorous growth scenario is highly implausible. PMID:19805043

  17. A Rapidly Declining Arctic Perennial Sea Ice Cover

    NASA Technical Reports Server (NTRS)

    Comiso, Josefino C.; Koblinsky, Chester J. (Technical Monitor)

    2002-01-01

    The perennial sea ice cover in the Arctic is shown to be declining at -8.9 plus or minus 2.0% per decade, using 22 years of satellite data. A sustained decline at this rate would mean the disappearance of the multiyear ice cover during this century and drastic changes in the seasonal characteristics of the Arctic ice cover. An apparent increase in the fraction of second year ice in the 1990s is also inferred suggesting an overall thinning of the ice cover while co-registered satellite surface temperatures show a warming trend of 0.8 plus or minus 0.6 K per decade in summer and a good correlation with the perennial ice data.

  18. Declining resilience of ecosystem functions under biodiversity loss.

    PubMed

    Oliver, Tom H; Isaac, Nick J B; August, Tom A; Woodcock, Ben A; Roy, David B; Bullock, James M

    2015-12-08

    The composition of species communities is changing rapidly through drivers such as habitat loss and climate change, with potentially serious consequences for the resilience of ecosystem functions on which humans depend. To assess such changes in resilience, we analyse trends in the frequency of species in Great Britain that provide key ecosystem functions--specifically decomposition, carbon sequestration, pollination, pest control and cultural values. For 4,424 species over four decades, there have been significant net declines among animal species that provide pollination, pest control and cultural values. Groups providing decomposition and carbon sequestration remain relatively stable, as fewer species are in decline and these are offset by large numbers of new arrivals into Great Britain. While there is general concern about degradation of a wide range of ecosystem functions, our results suggest actions should focus on particular functions for which there is evidence of substantial erosion of their resilience.

  19. Faint UBVRI Standard Star Fields at +50° Declination

    NASA Astrophysics Data System (ADS)

    Clem, James L.; Landolt, Arlo U.

    2016-10-01

    Precise and accurate CCD-based UBVRI photometry is presented for ˜2000 stars distributed around the sky in a declination zone centered approximately at +50°. Their photometry has been calibrated to the standard Johnson UBV and Kron-Cousins RI systems through observations of the UBVRI standard stars presented in the various works of Landolt. The magnitude and color range for these stars are 12 ≲ V ≲ 22 and -0.3 ≲ (B - V) ≲ 1.8, respectively. Each star averages 13 measures in each UBVRI filter from data taken on 41 different photometric nights obtained over a 21 month period. Hence, there now exists a network of faint UBVRI photometric standard stars centered on the declination zones δ = -50°, 0°, and +50°.

  20. Declining hepatitis A seroprevalence: a global review and analysis.

    PubMed Central

    Jacobsen, K. H.; Koopman, J. S.

    2004-01-01

    Hepatitis A virus (HAV) is spread by faecal-oral contact or ingestion of contaminated food or water. Lifelong immunity is conferred by infection or vaccination, so anti-HAV seroprevalence studies can be used to indicate which populations are susceptible to infection. Seroprevalence rates are highly correlated with socioeconomic status and access to clean water and sanitation. Increasing household income, education, water quality and quantity, sanitation, and hygiene leads to decreases in HAV prevalence. Japan, Australia, New Zealand, Canada, the United States, and most European nations have low anti-HAV rates. Although anti-HAV rates remain high in most Latin American, Asian, and Middle Eastern nations, average seroprevalence rates are declining. Surveys from Africa generally indicate no significant decline in anti-HAV rates. Because the severity of illness increases with age, populations with a high proportion of susceptible adults should consider targeted vaccination programmes. PMID:15635957

  1. Improving Recruitment in Clinical Trials: Why Eligible Participants Decline

    PubMed Central

    Brintnall-Karabelas, Julie; Sung, Susanna; Cadman, Mary Ellen; Squires, Carol; Whorton, Katherine; Pao, Maryland

    2011-01-01

    There is a need to explore why protocol-eligible subjects refuse participation in clinical trials. Without a clear understanding, participation by representative populations will be an ongoing obstacle to recruitment. This descriptive research study analyzes frequency data regarding a sample of 965 individuals who, despite being eligible for studies with the National Institute of Mental Health intramural program, declined research participation. Overall, responses regarding reasons for declining fell into the following five categories: a result of specific protocol issues; inconvenience; for other reasons not mentioned; financial reasons; and, lastly, decided to participate elsewhere. The results of this study identify common factors which suggest there are steps that investigators can take to better accommodate the needs of the public and, consequently, improve research participation. PMID:21460590

  2. Does conservation on farmland contribute to halting the biodiversity decline?

    PubMed

    Kleijn, David; Rundlöf, Maj; Scheper, Jeroen; Smith, Henrik G; Tscharntke, Teja

    2011-09-01

    Biodiversity continues to decline, despite the implementation of international conservation conventions and measures. To counteract biodiversity loss, it is pivotal to know how conservation actions affect biodiversity trends. Focussing on European farmland species, we review what is known about the impact of conservation initiatives on biodiversity. We argue that the effects of conservation are a function of conservation-induced ecological contrast, agricultural land-use intensity and landscape context. We find that, to date, only a few studies have linked local conservation effects to national biodiversity trends. It is therefore unknown how the extensive European agri-environmental budget for conservation on farmland contributes to the policy objectives to halt biodiversity decline. Based on this review, we identify new research directions addressing this important knowledge gap.

  3. Nutritional management of older adults with cognitive decline and dementia.

    PubMed

    Ogawa, Sumito

    2014-04-01

    Age-related cognitive decline is a main predictor of disability among elderly people, and with the continued expansion of the aging population and the increase in life expectancy, the prevalence of mild cognitive impairment and dementia represented by Alzheimer's disease (AD), which is a multifactorial neurodegenerative disorder of older adults, have increased. Recent epidemiological and observational studies suggest a relationship exists between lifestyle factors, including nutrition and diet, and cognitive function in aging adults. It is also suggested that malnutrition and nutrient deficiencies are associated with cognitive decline in patients with dementia. There are a variety of nutritional factors, including nutritional status and dietary patterns, that might be associated with cognitive function, and specific micronutrients and dietary components have been suggested to have an association with cognitive function as well. Based on these findings and evidence, evaluation of nutritional state, as well as nutritional intervention, might be able to play a role in the management and prevention of dementia.

  4. Declining resilience of ecosystem functions under biodiversity loss

    PubMed Central

    Oliver, Tom H.; Isaac, Nick J. B.; August, Tom A.; Woodcock, Ben A.; Roy, David B.; Bullock, James M.

    2015-01-01

    The composition of species communities is changing rapidly through drivers such as habitat loss and climate change, with potentially serious consequences for the resilience of ecosystem functions on which humans depend. To assess such changes in resilience, we analyse trends in the frequency of species in Great Britain that provide key ecosystem functions—specifically decomposition, carbon sequestration, pollination, pest control and cultural values. For 4,424 species over four decades, there have been significant net declines among animal species that provide pollination, pest control and cultural values. Groups providing decomposition and carbon sequestration remain relatively stable, as fewer species are in decline and these are offset by large numbers of new arrivals into Great Britain. While there is general concern about degradation of a wide range of ecosystem functions, our results suggest actions should focus on particular functions for which there is evidence of substantial erosion of their resilience. PMID:26646209

  5. Progress, decline, and the public uptake of climate science.

    PubMed

    Rudiak-Gould, Peter

    2014-02-01

    Previous research has sought to explain public perception of climate change science in terms of individuals' "prior commitment" to such ideological stances as just-world belief, system justification, and liberalism/conservatism. One type of prior commitment that has received little formal attention in the literature is narratives of the moral trajectory of society. A theory of climate science uptake based on beliefs in societal progress or decline is more easily portable to non-Western settings; in a case study of global warming attitudes in the Marshall Islands, trajectory narratives indeed account for public belief, concern, blame, and response more aptly than existing theories, and accord well with qualitative analysis of Marshallese climate change discourse. In Western settings, progress/decline narratives may explain much of the variation in climate change attitudes previously accounted for by other ideological variables, promising a more penetrating explanation for the divergence of climate change attitudes within and between societies.

  6. Air pollution and forest decline near Mexico City.

    PubMed

    Tovar, D C

    1989-04-01

    The forests of Abies religiosa Schl. et Cham. in the north and the northeast slopes of the mountains of the southwestern region of the Valley of Mexico are in an acute process of decline, particularly the fir forest of the Cultural and Recreational Park Desierto de los Leones. The mortality of the trees began in 1981, and by 1987 30% of the trees of the Park had died; the mortality continues. The surviving trees are in a very poor crown condition, having thin crowns with many dead branches. in the light of current knowledge air pollution, in particular the oxidant gases (ozone), are the primary cause of decline, but other conditions or agents (age of the trees and diseases) could be contributing factors in the dying of the trees.

  7. Decline of spectacled eiders nesting in western Alaska

    USGS Publications Warehouse

    Stehn, Robert A.; Dau, Christian P.; Conant, Bruce; Butler, William I.

    1993-01-01

    Spectacled eider (Somateria fischeri) populations in western Alaska are now less than 4% of the numbers estimated in the early 1970s. In 1992, an estimated 1721 nesting pairs remained on the Yukon-Kuskokwim Delta. Causes of this rapid and continuing decline of -14% per year are undocumented. Many aspects of spectacled eider biology remain unknown, including their marine foraging habitats, food items, migratory movements, and population ecology. A review of some biological characteristics and possible threats to the species suggests the importance of quantifying potential impacts from parasites and disease, subsistence harvest, predation during brood rearing, and alteration of Bering Sea food resources. Factors causing the population decline of spectacled eiders must be determined and appropriate actions taken to reverse the trend.

  8. Macro-invertebrate decline in surface water polluted with imidacloprid.

    PubMed

    Van Dijk, Tessa C; Van Staalduinen, Marja A; Van der Sluijs, Jeroen P

    2013-01-01

    Imidacloprid is one of the most widely used insecticides in the world. Its concentration in surface water exceeds the water quality norms in many parts of the Netherlands. Several studies have demonstrated harmful effects of this neonicotinoid to a wide range of non-target species. Therefore we expected that surface water pollution with imidacloprid would negatively impact aquatic ecosystems. Availability of extensive monitoring data on the abundance of aquatic macro-invertebrate species, and on imidacloprid concentrations in surface water in the Netherlands enabled us to test this hypothesis. Our regression analysis showed a significant negative relationship (P<0.001) between macro-invertebrate abundance and imidacloprid concentration for all species pooled. A significant negative relationship was also found for the orders Amphipoda, Basommatophora, Diptera, Ephemeroptera and Isopoda, and for several species separately. The order Odonata had a negative relationship very close to the significance threshold of 0.05 (P = 0.051). However, in accordance with previous research, a positive relationship was found for the order Actinedida. We used the monitoring field data to test whether the existing three water quality norms for imidacloprid in the Netherlands are protective in real conditions. Our data show that macrofauna abundance drops sharply between 13 and 67 ng l(-1). For aquatic ecosystem protection, two of the norms are not protective at all while the strictest norm of 13 ng l(-1) (MTR) seems somewhat protective. In addition to the existing experimental evidence on the negative effects of imidacloprid on invertebrate life, our study, based on data from large-scale field monitoring during multiple years, shows that serious concern about the far-reaching consequences of the abundant use of imidacloprid for aquatic ecosystems is justified.

  9. Macro-Invertebrate Decline in Surface Water Polluted with Imidacloprid

    PubMed Central

    Van Dijk, Tessa C.; Van Staalduinen, Marja A.; Van der Sluijs, Jeroen P.

    2013-01-01

    Imidacloprid is one of the most widely used insecticides in the world. Its concentration in surface water exceeds the water quality norms in many parts of the Netherlands. Several studies have demonstrated harmful effects of this neonicotinoid to a wide range of non-target species. Therefore we expected that surface water pollution with imidacloprid would negatively impact aquatic ecosystems. Availability of extensive monitoring data on the abundance of aquatic macro-invertebrate species, and on imidacloprid concentrations in surface water in the Netherlands enabled us to test this hypothesis. Our regression analysis showed a significant negative relationship (P<0.001) between macro-invertebrate abundance and imidacloprid concentration for all species pooled. A significant negative relationship was also found for the orders Amphipoda, Basommatophora, Diptera, Ephemeroptera and Isopoda, and for several species separately. The order Odonata had a negative relationship very close to the significance threshold of 0.05 (P = 0.051). However, in accordance with previous research, a positive relationship was found for the order Actinedida. We used the monitoring field data to test whether the existing three water quality norms for imidacloprid in the Netherlands are protective in real conditions. Our data show that macrofauna abundance drops sharply between 13 and 67 ng l−1. For aquatic ecosystem protection, two of the norms are not protective at all while the strictest norm of 13 ng l−1 (MTR) seems somewhat protective. In addition to the existing experimental evidence on the negative effects of imidacloprid on invertebrate life, our study, based on data from large-scale field monitoring during multiple years, shows that serious concern about the far-reaching consequences of the abundant use of imidacloprid for aquatic ecosystems is justified. PMID:23650513

  10. Assessing the Decline in the National Saving Rate

    DTIC Science & Technology

    1993-04-01

    I1 8 ASSESSING THE DECLINE IN THE NATIONAL SAVING RATE April 1993 plain the connection between the processes of timber lands. Intangible assets include...increasing stocks of productive assets. And assets. The increase in assets can take place intangible assets contribute to living stan- either at home, through...obsolescence, physical deterioration, and acci- Both tangible and intangible assets are fi- dents. Because new investment involves ac- nanced from

  11. Dispositional optimism and terminal decline in global quality of life.

    PubMed

    Zaslavsky, Oleg; Palgi, Yuval; Rillamas-Sun, Eileen; LaCroix, Andrea Z; Schnall, Eliezer; Woods, Nancy F; Cochrane, Barbara B; Garcia, Lorena; Hingle, Melanie; Post, Stephen; Seguin, Rebecca; Tindle, Hilary; Shrira, Amit

    2015-06-01

    We examined whether dispositional optimism relates to change in global quality of life (QOL) as a function of either chronological age or years to impending death. We used a sample of 2,096 deceased postmenopausal women from the Women's Health Initiative clinical trials who were enrolled in the 2005-2010 Extension Study and for whom at least 1 global QOL and optimism measure were analyzed. Growth curve models were examined. Competing models were contrasted using model fit criteria. On average, levels of global QOL decreased with both higher age and closer proximity to death (e.g., M(score) = 7.7 eight years prior to death vs. M(score) = 6.1 one year prior to death). A decline in global QOL was better modeled as a function of distance to death (DtD) than as a function of chronological age (Bayesian information criterion [BIC](DtD) = 22,964.8 vs. BIC(age) = 23,322.6). Optimism was a significant correlate of both linear (estimate(DtD) = -0.01, SE(DtD) = 0.005; ρ = 0.004) and quadratic (estimate(DtD) = -0.006, SE(DtD) = 0.002; ρ = 0.004) terminal decline in global QOL so that death-related decline in global QOL was steeper among those with a high level of optimism than those with a low level of optimism. We found that dispositional optimism helps to maintain positive psychological perspective in the face of age-related decline. Optimists maintain higher QOL compared with pessimists when death-related trajectories were considered; however, the gap between those with high optimism and those with low optimism progressively attenuated with closer proximity to death, to the point that is became nonsignificant at the time of death.

  12. Persistent Ischemic Stroke Disparities despite Declining Incidence in Mexican Americans

    PubMed Central

    Morgenstern, Lewis B.; Smith, Melinda A.; Sanchez, Brisa N.; Brown, Devin L.; Zahuranec, Darin B.; Garcia, Nelda; Kerber, Kevin A.; Skolarus, Lesli E.; Meurer, William J.; Burke, James F.; Adelman, Eric E.; Baek, Jonggyu; Lisabeth, Lynda D.

    2015-01-01

    Objective To determine trends in ischemic stroke incidence among Mexican Americans and non-Hispanic whites. Methods We performed population-based stroke surveillance from January 1, 2000 to December 31, 2010 in Corpus Christi, Texas. Ischemic stroke patients 45 years and older were ascertained from potential sources, and charts were abstracted. Neurologists validated cases based on source documentation blinded to ethnicity and age. Crude and age-, sex-, and ethnicity-adjusted annual incidence was calculated for first ever completed ischemic stroke. Poisson regression models were used to calculate adjusted ischemic stroke rates, rate ratios, and trends. Results There were 2,604 ischemic strokes in Mexican Americans and 2,042 in non-Hispanic whites. The rate ratios (Mexican American:non-Hispanic white) were 1.94 (95% confidence interval [CI] = 1.67–2.25), 1.50 (95% CI = 1.35– 1.67), and 1.00 (95% CI = 0.90–1.11) among those aged 45 to 59, 60 to 74, and 75 years and older, respectively, and 1.34 (95% CI = 1.23–1.46) when adjusted for age. Ischemic stroke incidence declined during the study period by 35.9% (95% CI = 25.9–44.5). The decline was limited to those aged ≥60 years, and happened in both ethnic groups similarly (p > 0.10), implying that the disparities seen in the 45- to 74-year age group persist unabated. Interpretation Ischemic stroke incidence rates have declined dramatically in the past decade in both ethnic groups for those aged ≥60 years. However, the disparity between Mexican American and non-Hispanic white stroke rates persists in those <75 years of age. Although the decline in stroke is encouraging, additional prevention efforts targeting young Mexican Americans are warranted. PMID:23868398

  13. Entorhinal cortex thickness predicts cognitive decline in Alzheimer's disease.

    PubMed

    Velayudhan, Latha; Proitsi, Petroula; Westman, Eric; Muehlboeck, J-Sebastian; Mecocci, Patrizia; Vellas, Bruno; Tsolaki, Magda; Kłoszewska, Iwona; Soininen, Hilkka; Spenger, Christian; Hodges, Angela; Powell, John; Lovestone, Simon; Simmons, Andrew

    2013-01-01

    Biomarkers for Alzheimer's disease (AD) based on non-invasive methods are highly desirable for diagnosis, disease progression, and monitoring therapeutics. We aimed to study the use of hippocampal volume, entorhinal cortex (ERC) thickness, and whole brain volume (WBV) as predictors of cognitive change in patients with AD. 120 AD subjects, 106 mild cognitive impairment (MCI), and 99 non demented controls (NDC) from the multi-center pan-European AddNeuroMed study underwent MRI scanning at baseline and clinical evaluations at quarterly follow-up up to 1 year. The rate of cognitive decline was estimated using cognitive outcomes, Mini-Mental State Examination (MMSE) and Alzheimer disease assessment scale-cognitive (ADAS-cog) by fitting a random intercept and slope model. AD subjects had smaller ERC thickness and hippocampal and WBV volumes compared to MCI and NDC subjects. Within the AD group, ERC > WBV was significantly associated with baseline cognition (MMSE, ADAS-cog) and disease severity (Clinical Dementia Rating). Baseline ERC thickness was associated with both longitudinal MMSE and ADAS-cog score changes and WBV with ADAS-cog decline. These data indicate that AD subjects with thinner ERC had lower baseline cognitive scores, higher disease severity, and predicted greater subsequent cognitive decline at one year follow up. ERC is a region known to be affected early in the disease. Therefore, the rate of atrophy in this structure is expected to be higher since neurodegeneration begins earlier. Focusing on structural analyses that predict decline can identify those individuals at greatest risk for future cognitive loss. This may have potential for increasing the efficacy of early intervention.

  14. Scientific meeting raises awareness of amphibian decline in Asia

    USGS Publications Warehouse

    Vredenburg, Vance; Wang, Yuezhao; Fellers, Gary M.

    2000-01-01

    Blood samples from 433 Peregrine Falcons (Falco peregrinus) during fall and spring migrations, 1976-80, indicated that most of their pesticide burden, primarily DDE, was accumulated on wintering grounds in Latin America. DDE in spring migrants returning from Latin America for the first time declined significantly from 1979 to 1980. Only about 10% of breeding-age females contained organochlorine residues likely to adversely affect reproduction. The organochlorine pesticide threat in Latin America may be diminishing.

  15. Hospital admissions and exercise capacity decline in patients with COPD.

    PubMed

    Ramon, Maria A; Gimeno-Santos, Elena; Ferrer, Jaume; Balcells, Eva; Rodríguez, Esther; de Batlle, Jordi; Gómez, Federico P; Sauleda, Jaume; Ferrer, Antoni; Barberà, Joan A; Agustí, Alvar; Gea, Joaquim; Rodriguez-Roisin, Robert; Antó, Josep M; Garcia-Aymerich, Judith

    2014-04-01

    Exercise capacity declines with time and is an important determinant of health status and prognosis in patients with chronic obstructive pulmonary disease (COPD). We hypothesised that hospital admissions are associated with exercise capacity decline in these patients. Clinical and functional variables were collected for 342 clinically stable COPD patients. The 6-min walk distance (6MWD) was determined at baseline and after a mean±sd of 1.7±0.3 years. Information on hospitalisations during follow-up was obtained from centralised administrative databases. Linear regression was used to model changes in exercise capacity. Patients were mostly male (92%), with mean±sd age 67.9±8.6 years, post-bronchodilator forced expiratory volume in 1 s 54±17% predicted and baseline 6MWD 433±93 m. During follow-up, 6MWD decreased by 21.9±51.0 m·year(-1) and 153 (45%) patients were hospitalised at least once. Among patients admitted only for COPD-related causes (50% of those ever admitted), the proportion presenting a clinically significant loss of 6MWD was higher than in patients admitted for only nonrespiratory conditions (53% versus 29%, p=0.040). After adjusting for confounders, annual 6MWD decline was greater (26 m·year(-1), 95% CI 13-38 m·year(-1); p<0.001) in patients with more than one all-cause hospitalisation per year, as compared with those with no hospitalisations. Hospitalisations are related to a greater decline in exercise capacity in COPD.

  16. Species decline: A perspective on extinction, recovery, and propagation

    USGS Publications Warehouse

    Carpenter, J.W.

    1983-01-01

    This keynote address was presented at the Conference on the Conservation of Endangered Species in Zoological Parks and Aquariums on April 18, 1982 at the National Aquarium in Baltimore. It outlines 1) future trends in the world's environment, resources, and population; 2) factors affecting species decline; 3) reasons for preserving life forms; and 4) techniques, with emphasis on captive propagation, used to assist in species recovery.

  17. Radiocesium in Swedish reindeer after the Chernobyl fallout: Seasonal variations and long-term decline

    SciTech Connect

    Ahman, B.; Ahman, G.

    1994-05-01

    Data about {sup 137}Cs activity concentrations in reindeer muscle were collected from different parts of Sweden during 1986-1992. The data were used to evaluate seasonal and geographical variations and long-term decline of {sup 137}Cs in reindeer. The seasonal variation is shown in an example from one of the most contaminated areas, the Saami community Vilhelmina Norra, where {sup 137}Cs activity concentrations in reindeer during winter exceed those found during summer by about 20 times. Activity concentrations of {sup 137}Cs in reindeer were fairly well correlated to ground deposition. The ratio between {sup 137}Cs in reindeer (kBq kg{sup -1} wet weight) and ground deposition (kBq m{sup -2}) was calculated to be 0.76 m{sup 2} kg{sup -1} for the winter period, January-April, in 1987. Activity concentrations of {sup 137}Cs in reindeer decreased significantly during the years 1986-1992. The decline was generally more rapid during September, November, and December [corresponding to an effective ecological half-life (T{sub Eff}) of 3.2 y] than during January-April when T{sub Eff} was calculated to 4.2 y. There was a general trend toward a slower decrease during the last of the observed years. 42 refs., 5 figs., 2 tabs.

  18. Radiocesium in Swedish reindeer after the Chernobyl fallout: seasonal variations and long-term decline.

    PubMed

    Ahman, B; Ahman, G

    1994-05-01

    Data about 137Cs activity concentrations in reindeer muscle were collected from different parts of Sweden during 1986-1992. The data were used to evaluate seasonal and geographical variations and long-term decline of 137Cs in reindeer. The seasonal variation is shown in an example from one of the most contaminated areas, the Saami community Vilhelmina Norra, where 137Cs activity concentrations in reindeer during winter exceed those found during summer by about 20 times. Activity concentrations of 137Cs in reindeer were fairly well correlated to ground deposition. The ratio between 137Cs in reindeer (kBq kg-1 wet weight) and ground deposition (kBq m-2) was calculated to be 0.76 m2 kg-1 for the winter period, January-April, in 1987. Activity concentrations of 137Cs in reindeer decreased significantly during the years 1986-1992. The decline was generally more rapid during September, November, and December [corresponding to an effective ecological half-life (TEff) of 3.2 y] than during January-April when TEff was calculated to 4.2 y. There was a general trend toward a slower decrease during the last of the observed years.

  19. Toxicity of two insecticides to California, USA, anurans and its relevance to declining amphibian populations

    USGS Publications Warehouse

    Sparling, D.W.; Fellers, G.M.

    2009-01-01

    Contaminants have been associated with population declines of several amphibian species in California (USA). Pesticides from the Central Valley of California are transported by winds into the Sierra Nevada Mountains and precipitate into wet meadows where amphibians breed. The present study examined the chronic toxicity of two of the insecticides most commonly used in the Central Valley and found in the mountains, chlorpyrifos and endosulfan, to larval Pacific treefrogs (Pseudacris regilla) and foothill yellow-legged frogs (Rana boylii) and discusses the implications of this toxicity to declining amphibian populations. Larvae were exposed to the pesticides from Gosner stages 25 to 26 through metamorphosis. The estimated median lethal concentration (LC50) for chlorpyrifos was 365 ??g/L in P. regilla and 66.5 ??g/L for R. boylii. Time to metamorphosis increased with concentration of chlorpyrifos in both species, and cholinesterase activity declined with exposure concentration in metamorphs of both species at Gosner stages 42 to 46. For endosulfan, the estimated LC50 was 15.6 ??g/L for P. regilla and 0.55 ??g/L for R. boylii. All R. boylii exposed to concentrations of greater than 0.8 ??g/L died before they entered metamorphosis. Pseudacris regilla remains relatively abundant and is broadly distributed throughout California. In contrast, R. boylii is among the species experiencing severe population declines. The present study adds to the increasing evidence that pesticides are very harmful to amphibians living in areas that are miles from sources of pesticide application. ?? 2009 SETAC.

  20. Glutamatergic regulation prevents hippocampal-dependent age-related cognitive decline through dendritic spine clustering

    PubMed Central

    Pereira, Ana C.; Lambert, Hilary K.; Grossman, Yael S.; Dumitriu, Dani; Waldman, Rachel; Jannetty, Sophia K.; Calakos, Katina; Janssen, William G.; McEwen, Bruce S.; Morrison, John H.

    2014-01-01

    The dementia of Alzheimer’s disease (AD) results primarily from degeneration of neurons that furnish glutamatergic corticocortical connections that subserve cognition. Although neuron death is minimal in the absence of AD, age-related cognitive decline does occur in animals as well as humans, and it decreases quality of life for elderly people. Age-related cognitive decline has been linked to synapse loss and/or alterations of synaptic proteins that impair function in regions such as the hippocampus and prefrontal cortex. These synaptic alterations are likely reversible, such that maintenance of synaptic health in the face of aging is a critically important therapeutic goal. Here, we show that riluzole can protect against some of the synaptic alterations in hippocampus that are linked to age-related memory loss in rats. Riluzole increases glutamate uptake through glial transporters and is thought to decrease glutamate spillover to extrasynaptic NMDA receptors while increasing synaptic glutamatergic activity. Treated aged rats were protected against age-related cognitive decline displayed in nontreated aged animals. Memory performance correlated with density of thin spines on apical dendrites in CA1, although not with mushroom spines. Furthermore, riluzole-treated rats had an increase in clustering of thin spines that correlated with memory performance and was specific to the apical, but not the basilar, dendrites of CA1. Clustering of synaptic inputs is thought to allow nonlinear summation of synaptic strength. These findings further elucidate neuroplastic changes in glutamatergic circuits with aging and advance therapeutic development to prevent and treat age-related cognitive decline. PMID:25512503

  1. Declining Abundance of Beaked Whales (Family Ziphiidae) in the California Current Large Marine Ecosystem

    PubMed Central

    Moore, Jeffrey E.; Barlow, Jay P.

    2013-01-01

    Beaked whales are among the most diverse yet least understood groups of marine mammals. A diverse set of mostly anthropogenic threats necessitates improvement in our ability to assess population status for this cryptic group. The Southwest Fisheries Science Center (NOAA) conducted six ship line-transect cetacean abundance surveys in the California Current off the contiguous western United States between 1991 and 2008. We used a Bayesian hidden-process modeling approach to estimate abundance and population trends of beaked whales using sightings data from these surveys. We also compiled records of beaked whale stranding events (3 genera, at least 8 species) on adjacent beaches from 1900 to 2012, to help assess population status of beaked whales in the northern part of the California Current. Bayesian posterior summaries for trend parameters provide strong evidence of declining beaked whale abundance in the study area. The probability of negative trend for Cuvier's beaked whale (Ziphius cavirostris) during 1991–2008 was 0.84, with 1991 and 2008 estimates of 10771 (CV = 0.51) and ≈7550 (CV = 0.55), respectively. The probability of decline for Mesoplodon spp. (pooled across species) was 0.96, with 1991 and 2008 estimates of 2206 (CV = 0.46) and 811 (CV = 0.65). The mean posterior estimates for average rate of decline were 2.9% and 7.0% per year. There was no evidence of abundance trend for Baird's beaked whale (Berardius bairdii), for which annual abundance estimates in the survey area ranged from ≈900 to 1300 (CV≈1.3). Stranding data were consistent with the survey results. Causes of apparent declines are unknown. Direct impacts of fisheries (bycatch) can be ruled out, but impacts of anthropogenic sound (e.g., naval active sonar) and ecosystem change are plausible hypotheses that merit investigation. PMID:23341907

  2. Satellite Observed Widespread Decline in Mongolian Grasslands Largely Due to Overgrazing

    NASA Technical Reports Server (NTRS)

    Hilker, Thomas; Natsagdorj, Enkhjargal; Waring, Richard H.; Lyapustin, Alexei; Wang, Yujie

    2014-01-01

    The Mongolian Steppe is one of the largest remaining grassland ecosystems. Recent studies have reported widespread decline of vegetation across the steppe and about 70 percent of this ecosystem is now considered degraded. Among the scientific community there has been an active debate about whether the observed degradation is related to climate, or overgrazing, or both. Here, we employ a new atmospheric correction and cloud screening algorithm (MAIAC) to investigate trends in satellite observed vegetation phenology. We relate these trends to changes in climate and domestic animal populations. A series of harmonic functions is fitted to MODIS observed phenological curves to quantify seasonal and inter-annual changes in vegetation. Our results show a widespread decline (of about 12 percent on average) in MODIS observed NDVI across the country but particularly in the transition zone between grassland and the Gobi desert, where recent decline was as much as 40 percent below the 2002 mean NDVI. While we found considerable regional differences in the causes of landscape degradation, about 80 percent of the decline in NDVI could be attributed to increase in livestock. Changes in precipitation were able to explain about 30 percent of degradation across the country as a whole but up to 50 percent in areas with denser vegetation cover (p0.05). Temperature changes, while significant, played only a minor role (r20.10, p0.05). Our results suggest that the cumulative effect of overgrazing is a primary contributor to the degradation of the Mongolian steppe and is at least partially responsible for desertification reported in previous studies.

  3. Declining abundance of beaked whales (family Ziphiidae) in the California Current large marine ecosystem.

    PubMed

    Moore, Jeffrey E; Barlow, Jay P

    2013-01-01

    Beaked whales are among the most diverse yet least understood groups of marine mammals. A diverse set of mostly anthropogenic threats necessitates improvement in our ability to assess population status for this cryptic group. The Southwest Fisheries Science Center (NOAA) conducted six ship line-transect cetacean abundance surveys in the California Current off the contiguous western United States between 1991 and 2008. We used a Bayesian hidden-process modeling approach to estimate abundance and population trends of beaked whales using sightings data from these surveys. We also compiled records of beaked whale stranding events (3 genera, at least 8 species) on adjacent beaches from 1900 to 2012, to help assess population status of beaked whales in the northern part of the California Current. Bayesian posterior summaries for trend parameters provide strong evidence of declining beaked whale abundance in the study area. The probability of negative trend for Cuvier's beaked whale (Ziphius cavirostris) during 1991-2008 was 0.84, with 1991 and 2008 estimates of 10771 (CV = 0.51) and ≈7550 (CV = 0.55), respectively. The probability of decline for Mesoplodon spp. (pooled across species) was 0.96, with 1991 and 2008 estimates of 2206 (CV = 0.46) and 811 (CV = 0.65). The mean posterior estimates for average rate of decline were 2.9% and 7.0% per year. There was no evidence of abundance trend for Baird's beaked whale (Berardius bairdii), for which annual abundance estimates in the survey area ranged from ≈900 to 1300 (CV≈1.3). Stranding data were consistent with the survey results. Causes of apparent declines are unknown. Direct impacts of fisheries (bycatch) can be ruled out, but impacts of anthropogenic sound (e.g., naval active sonar) and ecosystem change are plausible hypotheses that merit investigation.

  4. Whole-body angular momentum in incline and decline walking.

    PubMed

    Silverman, Anne K; Wilken, Jason M; Sinitski, Emily H; Neptune, Richard R

    2012-04-05

    Angular momentum is highly regulated over the gait cycle and is important for maintaining dynamic stability and control of movement. However, little is known regarding how angular momentum is regulated on irregular surfaces, such as slopes, when the risk of falling is higher. This study examined the three-dimensional whole-body angular momentum patterns of 30 healthy subjects walking over a range of incline and decline angles. The range of angular momentum was either similar or reduced on decline surfaces and increased on incline surfaces relative to level ground, with the greatest differences occurring in the frontal and sagittal planes. These results suggest that angular momentum is more tightly controlled during decline walking when the risk of falling is greater. In the frontal plane, the range of angular momentum was strongly correlated with the peak hip and knee abduction moments in early stance. In the transverse plane, the strongest correlation occurred with the knee external rotation peak in late stance. In the sagittal plane, all external moment peaks were correlated with the range of angular momentum. The peak ankle plantarflexion, knee flexion and hip extension moments were also strongly correlated with the sagittal-plane angular momentum. These results highlight how able-bodied subjects control angular momentum differently on sloped surfaces relative to level walking and provide a baseline for comparison with pathological populations that are more susceptible to falling.

  5. Can education rescue genetic liability for cognitive decline?

    PubMed

    Cook, C Justin; Fletcher, Jason M

    2015-02-01

    Although there is a vast literature linking education and later health outcomes, the mechanisms underlying these associations are relatively unknown. In the spirit of some medical literature that leverages developmental abnormalities to understand mechanisms of normative functioning, we explore the ability of higher educational attainments to "rescue" biological/genetic liabilities in brain function through inheritance of a variant of the APOE gene shown to lead to cognitive decline, dementia, and Alzheimer's disease in old age. Deploying a between-sibling design that allows quasi-experimental variation in genotype and educational attainment within a standard gene-environment interaction framework, we show evidence that the genetic effects of the "risky" APOE variant on old-age cognitive decline are absent in individuals who complete college (vs. high school graduates). Auxiliary analyses suggest that the likely mechanisms of education are most consistent through changing brain processes (i.e., "how we think") and potentially building cognitive reserves, rather than alleviating old age cognitive decline through the channels of higher socioeconomic status and resources over the life course.

  6. Longitudinal association between hippocampus atrophy and episodic-memory decline.

    PubMed

    Gorbach, Tetiana; Pudas, Sara; Lundquist, Anders; Orädd, Greger; Josefsson, Maria; Salami, Alireza; de Luna, Xavier; Nyberg, Lars

    2017-03-01

    There is marked variability in both onset and rate of episodic-memory decline in aging. Structural magnetic resonance imaging studies have revealed that the extent of age-related brain changes varies markedly across individuals. Past studies of whether regional atrophy accounts for episodic-memory decline in aging have yielded inconclusive findings. Here we related 15-year changes in episodic memory to 4-year changes in cortical and subcortical gray matter volume and in white-matter connectivity and lesions. In addition, changes in word fluency, fluid IQ (Block Design), and processing speed were estimated and related to structural brain changes. Significant negative change over time was observed for all cognitive and brain measures. A robust brain-cognition change-change association was observed for episodic-memory decline and atrophy in the hippocampus. This association was significant for older (65-80 years) but not middle-aged (55-60 years) participants and not sensitive to the assumption of ignorable attrition. Thus, these longitudinal findings highlight medial-temporal lobe system integrity as particularly crucial for maintaining episodic-memory functioning in older age.

  7. Assessing the Factors of Regional Growth Decline of Sugar Maple

    NASA Astrophysics Data System (ADS)

    Bishop, D. A.; Beier, C. M.; Pederson, N.; Lawrence, G. B.; Stella, J. C.; Sullivan, T. J.

    2014-12-01

    Sugar maple (Acer saccharum Marsh) is among the most ecologically, economically and culturally important trees in North America, but has experienced a decline disease across much of its range. We investigated the climatic and edaphic factors associated with A. saccharum growth in the Adirondack Mountains (USA) using a well-replicated tree-ring network incorporating a range of soil fertility (base cation availability). We found that nearly 3 in 4 A. saccharum trees exhibited declining growth rates during the last several decades, regardless of tree age or size. Although diameter growth was consistently higher on base-rich soils, the negative trends in growth were largely consistent across the soil chemistry gradient. Sensitivity of sugar maple growth to climatic variability was overall weaker than expected, but were also non-stationary during the 20th century. We observed increasingly positive responses to late-winter precipitation, increasingly negative responses to growing season temperatures, and strong positive responses to moisture availability during the 1960s drought that became much weaker during the recent pluvial. Further study is needed of these factors and their interactions as potential mechanisms for sugar maple growth decline.

  8. Flow rate decline of steam wells in fractured geothermal reservoirs

    SciTech Connect

    Bodvarsson, G.S.; Witherspoon, P.A.

    1985-01-01

    Decline curves are commonly used at The Geysers geothermal field to assess the generating capacity of a producing lease. It is generally assumed that wells will initially be drilled using 40-acre (400 m) spacing, with infill drilling used later to provide additional producing wells as needed. It is commonly believed that the final well spacing should not be less than 10 acres (200 m). Decline curves are used with this approach to estimate the number of make-up wells during a project lifetime (up to 30 years), as well as the appropriate plant size (MWe). A rather simple two-dimensional model was used to investigate the factors that control flow rate decline in steam wells. The effects of parameters such as fracture spacing and permeability are considered, as well as the effects of permeability, porosity and initial liquid saturation in the rock matrix. Also, the conventional P/z method that is commonly used in analyzing gas well production is investigated in terms of its applicability to fractured vapor dominated systems.

  9. Decline of speech understanding and auditory thresholds in the elderly

    NASA Astrophysics Data System (ADS)

    Divenyi, Pierre L.; Stark, Philip B.; Haupt, Kara M.

    2005-08-01

    A group of 29 elderly subjects between 60.0 and 83.7 years of age at the beginning of the study, and whose hearing loss was not greater than moderate, was tested twice, an average of 5.27 years apart. The tests measured pure-tone thresholds, word recognition in quiet, and understanding of speech with various types of distortion (low-pass filtering, time compression) or interference (single speaker, babble noise, reverberation). Performance declined consistently and significantly between the two testing phases. In addition, the variability of speech understanding measures increased significantly between testing phases, though the variability of audiometric measurements did not. A right-ear superiority was observed but this lateral asymmetry did not increase between testing phases. Comparison of the elderly subjects with a group of young subjects with normal hearing shows that the decline of speech understanding measures accelerated significantly relative to the decline in audiometric measures in the seventh to ninth decades of life. On the assumption that speech understanding depends linearly on age and audiometric variables, there is evidence that this linear relationship changes with age, suggesting that not only the accuracy but also the nature of speech understanding evolves with age.

  10. Diagnosing the decline in pharmaceutical R&D efficiency.

    PubMed

    Scannell, Jack W; Blanckley, Alex; Boldon, Helen; Warrington, Brian

    2012-03-01

    The past 60 years have seen huge advances in many of the scientific, technological and managerial factors that should tend to raise the efficiency of commercial drug research and development (RD). Yet the number of new drugs approved per billion US dollars spent on RD has halved roughly every 9 years since 1950, falling around 80-fold in inflation-adjusted terms. There have been many proposed solutions to the problem of declining RD efficiency. However, their apparent lack of impact so far and the contrast between improving inputs and declining output in terms of the number of new drugs make it sensible to ask whether the underlying problems have been correctly diagnosed. Here, we discuss four factors that we consider to be primary causes, which we call the 'better than the Beatles' problem; the 'cautious regulator' problem; the 'throw money at it' tendency; and the 'basic research-brute force' bias. Our aim is to provoke a more systematic analysis of the causes of the decline in RD efficiency.

  11. Theoretical explanations of the rapid fertility decline in China.

    PubMed

    Wu, C

    1986-07-01

    A 1982 population census recorded China's fertility rate in 1982 at 2.6; recent statistics of China's State Statistics Bureau record China's 1984 birth rate at 17 per 1000 and the total fertility rate at 1.94. Wu Cangping asserts that this world-recognized rapid fertility decline is not due to any compulsory governmental restrictions on fertility, but to the people's willingness to control fertility voluntarily. He cites a number of socioeconomic factors contributing to this voluntary decline in China's birth rates: 1) change of family function; 2) decline of mortality, particularly infant mortality; 3) improvement in the educational level; 4) improvement in women's social status, especially increased employment; 5) better social security services for the elderly; 6) the preference for modern ways of production and life; and 7) the availability of information on population and birth control. He attributes these factors to the socialist system with its nationalized production, centralized planning of the national economy, and the even distribution system which prevents polarization of earning. In addition, reforms have been carried out in all aspects of social life and recent advances have been made in science and technology. All of these factors have resulted in a more rapid fertility transition in China as compared to that of developed countries in their past and that of developing countries at present.

  12. Patterns and ecosystem consequences of shark declines in the ocean.

    PubMed

    Ferretti, Francesco; Worm, Boris; Britten, Gregory L; Heithaus, Michael R; Lotze, Heike K

    2010-08-01

    Whereas many land predators disappeared before their ecological roles were studied, the decline of marine apex predators is still unfolding. Large sharks in particular have experienced rapid declines over the last decades. In this study, we review the documented changes in exploited elasmobranch communities in coastal, demersal, and pelagic habitats, and synthesize the effects of sharks on their prey and wider communities. We show that the high natural diversity and abundance of sharks is vulnerable to even light fishing pressure. The decline of large predatory sharks reduces natural mortality in a range of prey, contributing to changes in abundance, distribution, and behaviour of small elasmobranchs, marine mammals, and sea turtles that have few other predators. Through direct predation and behavioural modifications, top-down effects of sharks have led to cascading changes in some coastal ecosystems. In demersal and pelagic communities, there is increasing evidence of mesopredator release, but cascading effects are more hypothetical. Here, fishing pressure on mesopredators may mask or even reverse some ecosystem effects. In conclusion, large sharks can exert strong top-down forces with the potential to shape marine communities over large spatial and temporal scales. Yet more empirical evidence is needed to test the generality of these effects throughout the ocean.

  13. Angular Declination and the Dynamic Perception of Egocentric Distance

    PubMed Central

    Gajewski, Daniel A.; Philbeck, John W.; Wirtz, Philip W.; Chichka, David

    2014-01-01

    The extraction of the distance between an object and an observer is fast when angular declination is informative, as it is with targets placed on the ground. To what extent does angular declination drive performance when viewing time is limited? Participants judged target distances in a real-world environment with viewing durations ranging from 36–220 ms. An important role for angular declination was supported by experiments showing that the cue provides information about egocentric distance even on the very first glimpse, and that it supports a sensitive response to distance in the absence of other useful cues. Performance was better at 220 ms viewing durations than for briefer glimpses, suggesting that the perception of distance is dynamic even within the time frame of a typical eye fixation. Critically, performance in limited viewing trials was better when preceded by a 15 second preview of the room without a designated target. The results indicate that the perception of distance is powerfully shaped by memory from prior visual experience with the scene. A theoretical framework for the dynamic perception of distance is presented. PMID:24099588

  14. Decline of ectomycorrhizal fungi following a mountain pine beetle epidemic.

    PubMed

    Treu, Roland; Karst, Justine; Randall, Morgan; Pec, Gregory J; Cigan, Paul W; Simard, Suzanne W; Cooke, Janice E K; Erbilgin, Nadir; Cahill, James F

    2014-04-01

    Forest die-off caused by mountain pine beetle (MPB; Dendroctonus ponderosa) is rapidly transforming western North American landscapes. The rapid and widespread death of lodgepole pine (Pinus contorta) will likely have cascading effects on biodiversity. One group particularly prone to such declines associated with MPB are ectomycorrhizal fungi, symbiotic organisms that can depend on pine for their survival, and are critical for stand regeneration. We evaluated the indirect effects of MPB on above- (community composition of epigeous sporocarps) and belowground (hyphal abundance) occurrences of ectomycorrhizal fungi across 11 forest stands. Along a gradient of mortality (0-82% pine killed), macromycete community composition changed; this shift was driven by a decrease in the species richness of ectomycorrhizal fungi. Both the proportion of species that were ectomycorrhizal and hyphal length in the soil declined with increased MPB-caused pine mortality; < 10% of sporocarp species were ectomycorrhizal in stands with high pine mortality compared with > 70% in stands without MPB attacks. The rapid range expansion of a native insect results not only in the widespread mortality of an ecologically and economically important pine species, but the effect of MPB may also be exacerbated by the concomitant decline of fungi crucial for recovery of these forests.

  15. Rapid body size decline in Alaskan Pleistocene horses before extinction.

    PubMed

    Guthrie, R Dale

    2003-11-13

    About 70% of North American large mammal species were lost at the end of the Pleistocene epoch. The causes of this extinction--the role of humans versus that of climate--have been the focus of much controversy. Horses have figured centrally in that debate, because equid species dominated North American late Pleistocene faunas in terms of abundance, geographical distribution, and species variety, yet none survived into the Holocene epoch. The timing of these equid regional extinctions and accompanying evolutionary changes are poorly known. In an attempt to document better the decline and demise of two Alaskan Pleistocene equids, I selected a large number of fossils from the latest Pleistocene for radiocarbon dating. Here I show that horses underwent a rapid decline in body size before extinction, and I propose that the size decline and subsequent regional extinction at 12,500 radiocarbon years before present are best attributed to a coincident climatic/vegetational shift. The present data do not support human overkill and several other proposed extinction causes, and also show that large mammal species responded somewhat individualistically to climate changes at the end of the Pleistocene.

  16. Both Financial and Cognitive Decline Predict Clinical Progression in MCI

    PubMed Central

    Gerstenecker, Adam; Triebel, Kristen L.; Martin, Roy; Snyder, Scott; Marson, Daniel C.

    2015-01-01

    We investigated the roles of financial/functional and cognitive abilities in predicting clinical progression in patients with mild cognitive impairment (MCI). In a longitudinal sample of 51 patients with consensus-conference diagnosed MCI likely due to Alzheimer’s disease (AD). Two-year change scores were calculated for a performance measure of functional ability, cognitive variables, and three outcome measures used to track progression in neurologic disorders. We examined patterns of financial and cognitive decline across the two-year study period, and used this data and the three outcome variables to construct discrete predictor models of clinical progression in MCI. We found that both financial skills and cognitive abilities declined over the two-year study period, were significantly associated with clinical progression, and contributed unique variance all three predictor models. The resulting models accounted for 40–75% of variance in clinical progression across outcome variables. Taken together, our results indicate that changes in both cognitive abilities and higher-order functional skills appear integral to understanding clinical progression in MCI likely due to AD. Specifically, declines in financial skills contribute unique variance to measures commonly used to track progression in neurological disorders associated with aging and thus represent an important functional marker of clinical progression in prodromal AD. PMID:26900988

  17. Cognitive decline, dietary factors and gut-brain interactions.

    PubMed

    Caracciolo, Barbara; Xu, Weili; Collins, Stephen; Fratiglioni, Laura

    2014-01-01

    Cognitive decline in elderly people often derives from the interaction between aging-related changes and age-related diseases and covers a large spectrum of clinical manifestations, from intact cognition through mild cognitive impairment and dementia. Epidemiological evidence supports the hypothesis that modifiable lifestyle-related factors are associated with cognitive decline, opening new avenues for prevention. Diet in particular has become the object of intense research in relation to cognitive aging and neurodegenerative disease. We reviewed the most recent findings in this rapidly expanding field. Some nutrients, such as vitamins and fatty acids, have been studied longer than others, but strong scientific evidence of an association is lacking even for these compounds. Specific dietary patterns, like the Mediterranean diet, may be more beneficial than a high consumption of single nutrients or specific food items. A strong link between vascular risk factors and dementia has been shown, and the association of diet with several vascular and metabolic diseases is well known. Other plausible mechanisms underlying the relationship between diet and cognitive decline, such as inflammation and oxidative stress, have been established. In addition to the traditional etiological pathways, new hypotheses, such as the role of the intestinal microbiome in cognitive function, have been suggested and warrant further investigation.

  18. Ectomycorrhizal fungal richness declines towards the host species' range edge.

    PubMed

    Lankau, Richard A; Keymer, Daniel P

    2016-07-01

    Plant range boundaries are generally considered to reflect abiotic conditions; however, a rise in negative or decline in positive species interactions at range margins may contribute to these stable boundaries. While evidence suggests that pollinator mutualisms may decline near range boundaries, little is known about other important plant mutualisms, including microbial root symbionts. Here, we used molecular methods to characterize root-associated fungal communities in populations of two related temperate tree species from across the species' range in the eastern United States. We found that ectomycorrhizal fungal richness on plant roots declined with distance from the centre of the host species range. These patterns were not evident in nonmycorrhizal fungal communities on roots nor in fungal communities in bulk soil. Climatic and soil chemical variables could not explain these biogeographic patterns, although these abiotic gradients affected other components of the bulk soil and rhizosphere fungal community. Depauperate ectomycorrhizal fungal communities may represent an underappreciated challenge to marginal tree populations, especially as rapid climate change pushes these populations outside their current climate niche.

  19. Solar and interplanetary signatures of declining of solar magnetic fields: Implications to the next solar cycle 25

    NASA Astrophysics Data System (ADS)

    Bisoi, Susanta Kumar; Janardhan, P.; Ananthakrishnan, S.; Tokumaru, M.; Fujiki, K.

    2015-08-01

    Our detailed study of solar surface magnetic fields at high-latitudes, using magnetic synoptic magnetograms of NSO/Kitt Peak observatory from 1975-2014, has shown a steady decline of the field strength since mid-1990's until mid-2014, i.e. the solar maximum of cycle 24. We also found that magnetic field strength at high-latitudes declines after each solar cycle maximum, and since cycle 24 is already past its peak implies that solar surface magnetic fields will be continuing to decline until solar minimum of cycle 24. In addition, interplanetary scintillation (IPS) measurements of solar wind micro-turbulence levels, from Solar and Terrestrial Environment Laboratory (STEL), Japan, have also shown a steady decline in sync with the declining surface fields. Even the heliospheric magnetic fields (HMF) at 1 AU have been declined much below the previously proposed floor level of HMF of ~4.6 nT. From study of a correlation between the high-latitude surface fields and the HMF at the last four solar minima we found a floor value of HMF of ~3.2 nT. Using the above correlation and the fact that the high-latitude surface fields is expected to decline until the minimum of cycle 24, we estimate the value of the HMF at the minimum of cycle 24 will be 3.8 ± 0.2 nT and the peak sunspot number for solar cycle 25 will be 56±12 suggesting a weak sunspot activity to be continued in cycle 25 too.

  20. A review of possible causes of nutrient enrichment and decline of endangered sucker populations in Upper Klamath Lake, Oregon

    USGS Publications Warehouse

    Bortleson, Gilbert C.; Fretwell, Marvin O.

    1993-01-01

    Ten possible causes for this excessive enrichment in nutrients are described. Three of these hypotheses are suggested for immediate testing because of large-scale changes in nutrient loading that may have occurred as a result of man’s activities. These three hypotheses relate nutrient enrichment to (1) conversion of marshland to agricultural land, (2) agricultural drainage from the basin, and (3) reservoir regulation. Eleven possible hypothetical causes for the decline in sucker populations also are described. The decline in sucker population may be related to excessive nutrient enrichment (eutrophication) of the lake.