New Experimental Limits on Macroscopic Forces Below 100 Microns

Results of an experimental search for new macroscopic forces with Yukawa range between 5 and 500 microns are presented. The experiment uses 1 kHz mechanical oscillators as test masses with a stiff conducting shield between them to suppress backgrounds. No signal is observed above the instrumental thermal noise after 22 hours of integration time. These results provide the strongest limits to date between 10 and 100 microns, improve on previous limits by as much as three orders of magnitude, and rule out half of the remaining parameter space for predictions of string-inspired models with low-energy supersymmetry breaking. New forces of four times gravitational strength or greater are excluded at the 95% confidence level for interaction ranges between 200 and 500 microns.Comment: 25 Pages, 7 Figures: Minor Correction

Ultrafast changes in lattice symmetry probed by coherent phonons

The electronic and structural properties of a material are strongly determined by its symmetry. Changing the symmetry via a photoinduced phase transition offers new ways to manipulate material properties on ultrafast timescales. However, in order to identify when and how fast these phase transitions occur, methods that can probe the symmetry change in the time domain are required. We show that a time-dependent change in the coherent phonon spectrum can probe a change in symmetry of the lattice potential, thus providing an all-optical probe of structural transitions. We examine the photoinduced structural phase transition in VO2 and show that, above the phase transition threshold, photoexcitation completely changes the lattice potential on an ultrafast timescale. The loss of the equilibrium-phase phonon modes occurs promptly, indicating a non-thermal pathway for the photoinduced phase transition, where a strong perturbation to the lattice potential changes its symmetry before ionic rearrangement has occurred.Comment: 14 pages 4 figure

Interfacing low-energy SAW nebulization with liquid chromatography-mass spectrometry for the analysis of biological samples

Soft ionization methods for the introduction of labile biomolecules into a mass spectrometer are of fundamental importance to biomolecular analysis. Previously, electrospray ionization (ESI) and matrix assisted laser desorption-ionization (MALDI) have been the main ionization methods used. Surface acoustic wave nebulization (SAWN) is a new technique that has been demonstrated to deposit less energy into ions upon ion formation and transfer for detection than other methods for sample introduction into a mass spectrometer (MS). Here we report the optimization and use of SAWN as a nebulization technique for the introduction of samples from a low flow of liquid, and the interfacing of SAWN with liquid chromatographic separation (LC) for the analysis of a protein digest. This demonstrates that SAWN can be a viable, low-energy alternative to ESI for the LC-MS analysis of proteomic samples

The individual and combined effects of obesity- and ageing-induced systemic inflammation on human skeletal muscle properties.

BACKGROUND/OBJECTIVES: The purpose of this study was to determine whether circulating pro-inflammatory cytokines, elevated with increased fat mass and ageing, were associated with muscle properties in young and older people with variable adiposity. SUBJECTS/METHODS: Seventy-five young (18-49 yrs) and 67 older (50-80 yrs) healthy, untrained men and women (BMI: 17-49 kg/m(2)) performed isometric and isokinetic plantar flexor maximum voluntary contractions (MVCs). Volume (Vm), fascicle pennation angle (FPA), and physiological cross-sectional area (PCSA) of the gastrocnemius medialis (GM) muscle were measured using ultrasonography. Voluntary muscle activation (VA) was assessed using electrical stimulation. GM specific force was calculated as GM fascicle force/PCSA. Percentage body fat (BF%), body fat mass (BFM), and lean mass (BLM) were assessed using dual-energy X-ray absorptiometry. Serum concentration of 12 cytokines was measured using multiplex luminometry. RESULTS: Despite greater Vm, FPA, and PCSA (P0.05), while IL-8 correlated with VA in older but not young adults (r⩾0.378, P⩽0.027). TNF-alpha correlated with MVC, lean mass, GM FPA and maximum force in older adults (r⩾0.458; P⩽0.048). CONCLUSIONS: The age- and adiposity-dependent relationships found here provide evidence that circulating pro-inflammatory cytokines may play different roles in muscle remodelling according to the age and adiposity of the individual.International Journal of Obesity accepted article preview online, 29 August 2016. doi:10.1038/ijo.2016.151

27 years of benthic and coral community dynamics on turbid, highly urbanised reefs off Singapore

Coral cover on reefs is declining globally due to coastal development, overfishing and climate change. Reefs isolated from direct human influence can recover from natural acute disturbances, but little is known about long term recovery of reefs experiencing chronic human disturbances. Here we investigate responses to acute bleaching disturbances on turbid reefs off Singapore, at two depths over a period of 27 years. Coral cover declined and there were marked changes in coral and benthic community structure during the first decade of monitoring at both depths. At shallower reef crest sites (3–4 m), benthic community structure recovered towards pre-disturbance states within a decade. In contrast, there was a net decline in coral cover and continuing shifts in community structure at deeper reef slope sites (6–7 m). There was no evidence of phase shifts to macroalgal dominance but coral habitats at deeper sites were replaced by unstable substrata such as fine sediments and rubble. The persistence of coral dominance at chronically disturbed shallow sites is likely due to an abundance of coral taxa which are tolerant to environmental stress. In addition, high turbidity may interact antagonistically with other disturbances to reduce the impact of thermal stress and limit macroalgal growth rates

Ageing and Long-Term Care Planning Perceptions of Hispanics in the USA: Evidence from a Case Study in New London, Connecticut

This paper explores the ageing attitudes and long-term care planning behavior of adult Hispanics in New London, Connecticut, a town with 30 thousand inhabitants that is rapidly ageing. We conducted six focus groups and had 37 participants share their ageing perceptions and long-term care needs. Our main findings suggest that informal care arrangements are vulnerable and unsustainable especially since women have historically and disproportionately provided most family eldercare even at their own personal and financial expense. Though male participants expected their female relatives to care for them when they age and need personal assistance, female participants did not necessarily expect the same from their relatives including their daughters. Also, both formal and government long-term care systems lack cultural competence and can be prohibitively costly. Therefore, Hispanics plan for ageing within their circles of family care and their resilience in a context of cultural exclusion and socio-economic disadvantage epitomizes strong intergenerational values. These support networks may help explain why may outlive whites (the Hispanic paradox ) who, on average, have higher wealth and education levels. Long-term care planning is a complex process that cannot be relayed to families only. Adequate training for family members from other relatives, and from private and government entities to appropriately convey this type of planning is vital to ensure that Hispanic families understand their options

Alpha-2-Macroglobulin Is Acutely Sensitive to Freezing and Lyophilization: Implications for Structural and Functional Studies.

Alpha-2-macroglobulin is an abundant secreted protein that is of particular interest because of its diverse ligand binding profile and multifunctional nature, which includes roles as a protease inhibitor and as a molecular chaperone. The activities of alpha-2-macroglobulin are typically dependent on whether its conformation is native or transformed (i.e. adopts a more compact conformation after interactions with proteases or small nucleophiles), and are also influenced by dissociation of the native alpha-2-macroglobulin tetramer into stable dimers. Alpha-2-macroglobulin is predominately present as the native tetramer in vivo; once purified from human blood plasma, however, alpha-2-macroglobulin can undergo a number of conformational changes during storage, including transformation, aggregation or dissociation. We demonstrate that, particularly in the presence of sodium chloride or amine containing compounds, freezing and/or lyophilization of alpha-2-macroglobulin induces conformational changes with functional consequences. These conformational changes in alpha-2-macroglobulin are not always detected by standard native polyacrylamide gel electrophoresis, but can be measured using bisANS fluorescence assays. Increased surface hydrophobicity of alpha-2-macroglobulin, as assessed by bisANS fluorescence measurements, is accompanied by (i) reduced trypsin binding activity, (ii) increased chaperone activity, and (iii) increased binding to the surfaces of SH-SY5Y neurons, in part, via lipoprotein receptors. We show that sucrose (but not glycine) effectively protects native alpha-2-macroglobulin from denaturation during freezing and/or lyophilization, thereby providing a reproducible method for the handling and long-term storage of this protein.Early Career Fellowship from the National Health and Medical Research Council GNT1012521(A.R.W.); Wellcome Trust Programme Grant (J.R.K., C.M.D.) 094425/Z/10/Z; Samsung GRO Grant (M.R.W.)This is the final version of the article. It first appeared from PLoS via http://dx.doi.org/10.1371/journal.pone.013003

Probing Galaxy Evolution in Massive Clusters Using ACT and DES: Splashback as a Cosmic Clock

We measure the projected number density profiles of galaxies and the splashback feature in clusters selected by the Sunyaev–Zel'dovich effect from the Advanced Atacama Cosmology Telescope (AdvACT) survey using galaxies observed by the Dark Energy Survey (DES). The splashback radius is consistent with CDM-only simulations and is located at ${2.4}_{-0.4}^{+0.3}\,\mathrm{Mpc}\,{h}^{-1}$. We split the galaxies on color and find significant differences in their profile shapes. Red and green-valley galaxies show a splashback-like minimum in their slope profile consistent with theory, while the bluest galaxies show a weak feature at a smaller radius. We develop a mapping of galaxies to subhalos in simulations and assign colors based on infall time onto their hosts. We find that the shift in location of the steepest slope and different profile shapes can be mapped to the average time of infall of galaxies of different colors. The steepest slope traces a discontinuity in the phase space of dark matter halos. By relating spatial profiles to infall time, we can use splashback as a clock to understand galaxy quenching. We find that red galaxies have on average been in clusters over 3.2 Gyr, green galaxies about 2.2 Gyr, while blue galaxies have been accreted most recently and have not reached apocenter. Using the full radial profiles, we fit a simple quenching model and find that the onset of galaxy quenching occurs after a delay of about a gigayear and that galaxies quench rapidly thereafter with an exponential timescale of 0.6 Gyr