As the world’s population ages, the prevalence of chronic diseases increases. Sarcopenia and osteoporosis are two conditions that are associated with aging, with similar risk factors that include ...genetics, endocrine function, and mechanical factors. Additionally, bone and muscle closely interact with each other not only anatomically, but also chemically and metabolically. Fat infiltration, a phenomenon observed in age-related bone and muscle loss, is highly prevalent and more severe in sarcopenic and osteoporotic subjects. Clinically, when individuals suffer a combination of both disorders, negative outcomes such as falls, fractures, loss of function, frailty, and mortality increase, thus generating significant personal and socio-economic costs. Therefore, it is suggested that when bone mineral density loss is synchronic with decreased muscle mass, strength, and function, it should be interpreted as a single diagnosis of osteosarcopenia, which may be preventable and treatable. Simple interventions such as resistance training, adequate protein and calcium dietary intake, associated with maintenance of appropriate levels of vitamin D, have a dual positive effect on bone and muscle, reducing falls, fractures, and, consequently, disability. It is essential that fracture prevention approaches—including postfracture management—involve assessment and treatment of both osteoporosis and sarcopenia. This is of particular importance as in older persons the combination of osteopenia/osteoporosis and sarcopenia has been proposed as a subset of frailer individuals at higher risk of institutionalization, falls, and fractures. This review summarizes osteosarcopenia epidemiology, pathophysiology, diagnosis, outcomes, and management strategies.
Recognizing International Status Duque, Marina G.
International studies quarterly,
09/2018, Letnik:
62, Številka:
3
Journal Article
Recenzirano
How do states achieve status? Although we rely on status to explain important phenomena in international politics—such as wars and the foreign policy of emerging powers—we still do not understand ...what status is or where it comes from. Previous research treats status as a function of state attributes, such as wealth and military capability. Following Weber, I argue that status depends on social recognition: it concerns identification processes in which an actor gains admission into a club once they follow the rules of membership. Therefore, systematic social processes, which cannot be reduced to state attributes, influence status. In particular, status is self-reinforcing. Moreover, social closure influences status—which implies that (1) a state’s existing relations influence its ability to achieve status and (2) states recognize similar states rather than states with the most impressive portfolio of certain attributes. To investigate the determinants of international status, I move beyond ranking states based on attributes to examine quantitatively how status emerges from state relations. Leveraging inferential network analysis, I examine state practices that express recognition—specifically, the network of embassies. The analysis indicates that self-reinforcing dynamics and social closure, rather than state attributes directly, drive status recognition.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Aqueous two-phase extraction has recently been demonstrated as a new method to separate single-wall carbon nanotubes (SWCNTs). In this work, we determined that the mechanism of separation is driven ...by the hydrophobicity of the surfactant, or combination of surfactants, at the SWCNT surface. This knowledge allowed us to develop a simple approach for obtaining highly enriched single-chirality suspensions in only 1 or 2 steps. These results were obtained by strategically combining multiple surfactants with different diameter-dependent binding affinities for SWCNTs and salts that readjust the surfactant structure within the mixed micelle surrounding the SWCNTs. The procedure is successfully applied to SWCNTs from different sources (CoMoCAT and HiPco) with various diameter distributions (from 0.53 to 1.2 nm). Each separation step is characterized by optical absorption, resonant Raman, and photoluminescence excitation spectroscopies. By determining the SWCNT sorting mechanism, we were able to develop a new set of parameters that separated another chirality.
Summary
Numerous sarcopenia definitions are not associated with increased falls-related hospitalization risk over 5 years to 9.5 years in older community-dwelling Australian women. Measures of muscle ...strength and physical function, but not appendicular lean mass (measured by dual-energy X-ray absorptiometry) may help discriminate the risk of falls-related hospitalization.
Introduction
The aim of this prospective, population-based cohort study of 903 Caucasian-Australian women (mean age 79.9 ± 2.6 years) was to compare the clinical utility of four sarcopenia definitions for the prediction of falls-related hospitalization over 9.5 years.
Methods
The four definitions were the United States Foundation for the National Institutes of Health (FNIH), the European Working Group on Sarcopenia in Older People (EWGSOP), and modified FNIH (AUS-POP
F
) and EWGSOP (AUS-POP
E
) definitions using Australian population-specific cut points (< 2 SD below the mean of young healthy Australian women). Components of sarcopenia including muscle strength, physical function, and appendicular lean mass (ALM) were quantified using hand grip strength, timed-up-and-go (TUG), and dual-energy X-ray absorptiometry (DXA), respectively. Incident 9.5-year falls-related hospitalization were captured by linked data.
Results
Baseline prevalence of sarcopenia according to FNIH (9.4%), EWGSOP (24.1%), AUS-POP
F
(12.0%), and AUS-POP
E
(10.7%) differed substantially. Sarcopenia did not increase the relative hazard ratio (HR) for falls-related hospitalization before or after adjustment for age (aHR): FNIH aHR 1.00 95%CI (0.69–1.47), EWGSOP aHR 1.20 95%CI (0.93–1.54), AUS-POP
F
aHR 0.96 95%CI (0.68–1.35), and AUS-POP
E
aHR 1.33 95%CI (0.94–1.88). When examining individual components of sarcopenia, only muscle strength and physical function but not ALM (adjusted for height
2
or BMI) were associated with falls-related hospitalization.
Conclusion
Current definitions of sarcopenia were not associated with falls-related hospitalization risk in this cohort of community-dwelling older Australian women. Finally, measures of muscle strength and physical function, but not ALM (measured by DXA) may help discriminate the risk of falls-related hospitalization.
The search for environmentally clean energy sources has spawned a wave of research into the use of carbon nanomaterials for photovoltaic applications. In particular, research using semiconducting ...single-walled carbon nanotubes has undergone dramatic transformations due to the availability of high quality samples through colloidal separation techniques. This has led to breakthrough discoveries on how energy and charge transport occurs in these materials and points to applications in energy harvesting. We present a review of the relevant photophysics of carbon nanotubes that dictate processes important for integration as active and passive material elements in thin film photovoltaics. Fundamental processes ranging from light absorption and internal conversion to exciton transport and dissociation are discussed in detail from both a spectroscopic and a device perspective. We also give a perspective on the future of these fascinating materials to be used as active and passive material elements in photovoltaics.
Density gradient ultracentrifugation (DGU) and fluorescence spectroscopy are used to probe the limiting behaviors of the dynamic response of surfactant structure at the single-walled carbon nanotube ...(SWNT) surface to reorganizing forces, including changes in surfactant concentration and electrolyte screening. DGU results indicate that, as surfactant (sodium dodecyl sulfate, SDS) concentration is increased, SDS adsorbed on metallic SWNTs becomes limited in its ability to reorganize before SDS adsorbed on semiconducting species. A diameter-dependent enhancement is observed in photoluminescence intensities from semiconducting SWNTS upon initial titration with NaCl. This response to electrostatic screening diminishes as SDS concentration is increased. The results are understood as a saturation of the surfactant structural response, defined as both a loss in ability to increase SDS loading at the SWNT surface and a loss in ability to reorient surface structure in response to a reorganizing force. Saturation of response is found to be reversible and also occurs as a result of restricting SDS mobility. These results confirm several aspects of recent molecular dynamics simulations of SDS behavior on SWNTs and have important implications for tunability of density-based separation approaches using cosurfactant systems that include SDS.
Ni
1−
x
Fe
x
O nanoparticles have been obtained by the co-precipitation chemical route. X-ray diffraction analyses using Rietveld refinement have shown a slight decrease in the microstrain and mean ...particle size as a function of the Fe content. The zero-field-cooling (ZFC) and field-cooling (FC) magnetization curves show superparamagnetic behavior at high temperatures and a low temperature peak (at
T
= 11 K), which is enhanced with increasing Fe concentration. Unusual behavior of the coercive field in the low temperature region and an exchange bias behavior were also observed. A decrease in the Fe concentration induces an increase in the exchange bias field. We argue that these behaviors can be linked with the strengthening of surface anisotropy caused by the incorporation of Fe ions.
An unusual increasing of magnetization (at
T
= 11 K) was observed, which is enhanced with an increase in Fe-doping concentration.
A New JNHA Section on Interviews with Experts Ruiz, Jorge G.; Duque, G.; Castillo-Gallego, C. ...
The Journal of nutrition, health & aging,
08/2023, Letnik:
27, Številka:
8
Journal Article
OBJECTIVES: In older persons, the combination of osteoporosis and sarcopenia has been proposed as a subset of frailer individuals at higher risk of falls and fractures. However, the particular ...nutritional status of the sarco-osteoporotic (SOP) patients remains unknown. The goal of this study was to obtain a comprehensive picture of nutritional status in SOP patients. DESIGN: Cross-sectional study. SETTING: Falls & Fractures Clinic, Nepean Hospital (Penrith, Australia). PARTICIPANTS: 680 subjects (mean age=79, 65% female) assessed between 2008–2013. MEASUREMENTS: Assessment included medical history, mini-nutritional assessment, physical examination, bone densitometry and body composition by DXA, and blood tests for nutritional status (albumin, creatinine, hemoglobin, vitamin D, vitamin B-12, calcium, phosphate and folate). Patients were divided in 4 groups: 1) osteopenia/osteoporosis (BMD<−1.0 SD); 2) sarcopenia; 3) SOP; and 4) normal (no sarcopenia/no osteoporosis). Difference between groups was assessed with one-way ANOVA and chi square analysis. Multivariable linear regression evaluated the association between the groups and measures of nutritional parameters. RESULTS: Sarcopenia was present in 47.4% of those with osteopenia (167/352) and 62.7% in those with osteoporosis (91/145). Mean age of the SOP was 80.4±7 years. SOP patients showed significantly higher prevalence of falls and fractures. Univariate analyses showed that SOP were more likely than normal to have a BMI< 25 (OR 2.42 95%CI 1.45–4.041, p<0.001), a MNA score <12 (OR 2.0, 95%CI 1.15–3.49, p<0.05), serum folate <20 nmol/L (OR 4.0 95%CI 1.35–11.87, p<0.01) and hemoglobin <120g/L (OR 2.0 95%CI 1.28–3.30, p<0.01). Multivariate analysis showed that a MNA score <12 was independently associated with SOP compared to normal when adjusted for age and gender. Hemoglobin <120g/L, BMI <25, and GDS >6 remained independently associated with SOP after adjustment for all variables including inflammatory conditions. Hypoalbuminemia (<35 g/L) was associated with just osteopenia/osteoporosis (OR: 2.03, 95%CI 1.08–3.81, p<0.01) and just sarcopenia (OR: 1.77, 95%CI 1.0–3.0, p<0.01) compared to normal. No differences in vitamin D, glomerular filtration rate, albumin, corrected calcium, phosphate, red blood cells folate or vitamin B12 levels were found between the subgroups. CONCLUSIONS: In approaching SOP patients, early prevention protocols directed to optimize their nutritional status would be a key strategy to prevent poor outcomes such as falls and fractures in this high risk population. Therefore, nutritional assessment and early nutritional supplementation should be essential domains in this strategy.
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