366 research outputs found
Age differences in free will and control perceptions across the lifespan and around the world
Variation in free will and control perceptions has been examined across the development of young children, adults, and in several different countries. In two studies (three samples; total N = 492,134), older adults believed less in free will, fatalistic determinism, and perceived less control over their lives than younger adults. In Study 2 (Samples 1 [48 countries] and 2 [99 countries]), control perceptions were highest among individuals who lived in countries that were more indulgent (versus restricted). Country-level characteristics often moderated the link between age and control perceptions, although variation in age differences was relatively small. The current studies are the largest and most comprehensive investigations of demographic and cultural differences in free will and control perceptions. The findings are discussed in the context of the mechanisms that drive changes in free will and control perceptions across the lifespan and across cultures
Low temperature decreases bone mass in mice: Implications for humans
ObjectivesHumans exhibit significant ecogeographic variation in bone size and shape. However, it is unclear how significantly environmental temperature influences cortical and trabecular bone, making it difficult to recognize adaptation versus acclimatization in past populations. There is some evidence that coldâinduced bone loss results from sympathetic nervous system activation and can be reduced by nonshivering thermogenesis (NST) via uncoupling protein (UCP1) in brown adipose tissue (BAT). Here we test two hypotheses: (1) low temperature induces impaired cortical and trabecular bone acquisition and (2) UCP1, a marker of NST in BAT, increases in proportion to degree of lowâtemperature exposure.MethodsWe housed wildtype C57BL/6J male mice in pairs at 26â°C (thermoneutrality), 22â°C (standard), and 20â°C (cool) from 3 weeks to 6 or 12âweeks of age with access to food and water ad libitum (N = 8/group).ResultsCool housed mice ate more but had lower body fat at 20â°C versus 26â°C. Mice at 20â°C had markedly lower distal femur trabecular bone volume fraction, thickness, and connectivity density and lower midshaft femur cortical bone area fraction versus mice at 26â°C (p <â.05 for all). UCP1 expression in BAT was inversely related to temperature.DiscussionThese results support the hypothesis that low temperature was detrimental to bone mass acquisition. Nonshivering thermogenesis in brown adipose tissue increased in proportion to lowâtemperature exposure but was insufficient to prevent bone loss. These data show that chronic exposure to low temperature impairs bone architecture, suggesting climate may contribute to phenotypic variation in humans and other hominins.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146428/1/ajpa23684.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146428/2/ajpa23684_am.pd
Do we know more about hypertension in Poland after the May Measurement Month 2017?-Europe
Elevated blood pressure (BP) is a worldwide burden, leading to over 10 million deaths yearly. May Measurement Month (MMM) is a global initiative organized by the International Society of Hypertension aimed at raising awareness of hypertension and the need for BP screening. An opportunistic cross-sectional survey of volunteers aged â„18 was carried out in May 2017. BP measurement, the definition of hypertension and statistical analysis followed the globally approved MMM17 Study Protocol. In Poland 5834 (98.9%, Caucasian) individuals were screened. After multiple imputation, 2601 (35.3%) had hypertension. Of individuals not receiving anti-hypertensive medication, 976 (20.6%) were hypertensive. Of individuals receiving anti-hypertensive medication, 532 (49.1%) had uncontrolled BP. In the crude screened group, 81.4% declared to not receive any anti-hypertensive treatment, while the remaining 18.6% were on such medications. In overweight and obese patients both systolic and diastolic BP were significantly higher than in normal weight and underweight subjects. In addition, BP measured on Sundays was significantly lower than on Mondays. MMM17 was one of the largest recent BP screening campaigns in Poland. We found that over 1/3 of participants were hypertensive. Almost half of the treated subjects had uncontrolled BP. These results suggest that opportunistic screening can identify substantial numbers with raised BP
Sequences of Regressions Distinguish Nonmechanical from Mechanical Associations between Metabolic Factors, Body Composition, and Bone in Healthy Postmenopausal Women
Background: There is increasing recognition of complex interrelations between the endocrine functions of bone and fat tissues or organs. Objective: The objective was to describe nonmechanical and mechanical links between metabolic factors, body composition, and bone with the use of graphical Markov models. Methods: Seventy postmenopausal women with a mean ± SD age of 62.3 ± 3.7 y and body mass index (in kg/m2) of 24.9 ± 3.8 were recruited. Bone outcomes were peripheral quantitative computed tomography measures of the distal and diaphyseal tibia, cross-sectional area (CSA), volumetric bone mineral density (vBMD), and cortical CSA. Biomarkers of osteoblast and adipocyte function were plasma concentrations of leptin, adiponectin, osteocalcin, undercarboxylated osteocalcin (UCOC), and phylloquinone. Body composition measurements were lean and percent fat mass, which were derived with the use of a 4-compartment model. Sequences of Regressions, a subclass of graphical Markov models, were used to describe the direct (nonmechanical) and indirect (mechanical) interrelations between metabolic factors and bone by simultaneously modeling multiple bone outcomes and their relation with biomarker outcomes with lean mass, percent fat mass, and height as intermediate explanatory variables. Results: The graphical Markov models showed both direct and indirect associations linking plasma leptin and adiponectin concentrations with CSA and vBMD. At the distal tibia, lean mass, height, and adiponectin-UCOC interaction were directly explanatory of CSA (R2 = 0.45); at the diaphysis, lean mass, percent fat mass, leptin, osteocalcin, and age-adiponectin interaction were directly explanatory of CSA (R2 = 0.49). The regression models exploring direct associations for vBMD were much weaker, with R2 = 0.15 and 0.18 at the distal and diaphyseal sites, respectively. Lean mass and UCOC were associated, and the global Markov property of the graph indicated that this association was explained by osteocalcin. Conclusions: This study, to our knowledge, offers a novel approach to the description of the complex physiological interrelations between adiponectin, leptin, and osteocalcin and the musculoskeletal system. There may be benefits to jointly targeting both systems to improve bone health
Stochastic Reaction-diffusion Equations Driven by Jump Processes
We establish the existence of weak martingale solutions to a class of second
order parabolic stochastic partial differential equations. The equations are
driven by multiplicative jump type noise, with a non-Lipschitz multiplicative
functional. The drift in the equations contains a dissipative nonlinearity of
polynomial growth.Comment: See journal reference for teh final published versio
The mitochondrial protein Sideroflexin 3 (SFXN3) influences neurodegeneration pathways in vivo
Synapses are a primary pathological target in neurodegenerative diseases. Identifying therapeutic targets at the synapse could delay progression of numerous conditions. The mitochondrial protein SFXN3 is a neuronally-enriched protein expressed in synaptic terminals and regulated by key synaptic proteins, including α-synuclein. We first show that SFXN3 uses the carrier import pathway to insert into the inner mitochondrial membrane. Using high-resolution proteomics on Sfxn3-KO mice synapses, we then demonstrate that SFXN3 influences proteins and pathways associated with neurodegeneration and cell death (including CSPα and Caspase-3), as well as neurological conditions (including Parkinsonâs disease and Alzheimerâs disease). Over-expression of SFXN3 orthologues in Drosophila models of Parkinsonâs Disease significantly reduced dopaminergic neuron loss. In contrast, the loss of SFXN3 was insufficient to trigger neurodegeneration in mice, indicating an anti- rather than pro-neurodegeneration role for SFXN3. Taken together, these results suggest a potential role for SFXN3 in the regulation of neurodegeneration pathways
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