Mangroves and salt marshes are among the most productive ecosystems in the global coastal ocean. Mangroves store more carbon (739 Mg CORG ha−1) than salt marshes (334 Mg CORG ha−1), but the latter ...sequester proportionally more (24%) net primary production (NPP) than mangroves (12%). Mangroves exhibit greater rates of gross primary production (GPP), aboveground net primary production (AGNPP) and plant respiration (RC), with higher PGPP/RC ratios, but salt marshes exhibit greater rates of below-ground NPP (BGNPP). Mangroves have greater rates of subsurface DIC production and, unlike salt marshes, exhibit active microbial decomposition to a soil depth of 1 m. Salt marshes release more CH4 from soil and creek waters and export more dissolved CH4, but mangroves release more CO2 from tidal waters and export greater amounts of particulate organic carbon (POC), dissolved organic carbon (DOC) and dissolved inorganic carbon (DIC), to adjacent waters. Both ecosystems contribute only a small proportion of GPP, RE (ecosystem respiration) and NEP (net ecosystem production) to the global coastal ocean due to their small global area, but contribute 72% of air–sea CO2 exchange of the world’s wetlands and estuaries and contribute 34% of DIC export and 17% of DOC + POC export to the world’s coastal ocean. Thus, both wetland ecosystems contribute disproportionately to carbon flow of the global coastal ocean.
Fluid-driven origami-inspired artificial muscles Li, Shuguang; Vogt, Daniel M.; Rus, Daniela ...
Proceedings of the National Academy of Sciences - PNAS,
12/2017, Volume:
114, Issue:
50
Journal Article
Peer reviewed
Open access
Artificial muscles hold promise for safe and powerful actuation for myriad common machines and robots. However, the design, fabrication, and implementation of artificial muscles are often limited by ...their material costs, operating principle, scalability, and single-degree-of-freedom contractile actuation motions. Here we propose an architecture for fluid-driven origami-inspired artificial muscles. This concept requires only a compressible skeleton, a flexible skin, and a fluid medium. A mechanical model is developed to explain the interaction of the three components. A fabrication method is introduced to rapidly manufacture low-cost artificial muscles using various materials and at multiple scales. The artificial muscles can be programed to achieve multiaxial motions including contraction, bending, and torsion. These motions can be aggregated into systems with multiple degrees of freedom, which are able to produce controllable motions at different rates. Our artificial muscles can be driven by fluids at negative pressures (relative to ambient). This feature makes actuation safer than most other fluidic artificial muscles that operate with positive pressures. Experiments reveal that these muscles can contract over 90% of their initial lengths, generate stresses of ∼600 kPa, and produce peak power densities over 2 kW/kg—all equal to, or in excess of, natural muscle. This architecture for artificial muscles opens the door to rapid design and low-cost fabrication of actuation systems for numerous applications at multiple scales, ranging from miniature medical devices to wearable robotic exoskeletons to large deployable structures for space exploration.
A series of six luminescent two-coordinate Cu(I) complexes were investigated bearing nonconventional N-heterocyclic carbene ligands, monoamido-aminocarbene (MAC*) and diamidocarbene (DAC*), along ...with carbazolyl (Cz) as well as mono- and dicyano-substituted Cz derivatives. The emission color can be systematically varied over 270 nm, from violet to red, through proper choice of the acceptor (carbene) and donor (carbazolyl) groups. The compounds exhibit photoluminescent quantum efficiencies up to 100% in fluid solution and polystyrene films with short decay lifetimes (τ ≈ 1 μs). The radiative rate constants for the Cu(I) complexes (k r = 105–106 s–1) are comparable to state of the art phosphorescent emitters with noble metals such as Ir and Pt. All complexes show strong solvatochromism due to the large dipole moment of the ground states and the transition dipole moment that is in the opposite direction. Temperature-dependent studies of (MAC*)Cu(Cz) reveal a small energy separation between the lowest singlet and triplet states (ΔE S1–T1 = 500 cm–1) and an exceptionally large zero-field splitting (ZFS = 85 cm–1). Organic light-emitting diodes (OLEDs) fabricated with (MAC*)Cu(Cz) as a green emissive dopant have high external quantum efficiencies (EQE = 19.4%) and brightness of 54 000 cd/m2 with modest roll-off at high currents. The complex can also serve as a neat emissive layer to make highly efficient OLEDs (EQE = 16.3%).
This book is a five-country empirical study of the causes and consequences of social and economic rights litigation. Detailed studies of Brazil, India, Indonesia, Nigeria, and South Africa present ...systematic and nuanced accounts of court activity on social and economic rights in each country. The book develops new methodologies for analyzing the sources of and variation in social and economic rights litigation, explains why actors are now turning to the courts to enforce social and economic rights, measures the aggregate impact of litigation in each country, and assesses the relevance of the empirical findings for legal theory. This book argues that courts can advance social and economic rights under the right conditions precisely because they are never fully independent of political pressures.
Abstract
Study Objectives
Multisensor wearable consumer devices allowing the collection of multiple data sources, such as heart rate and motion, for the evaluation of sleep in the home environment, ...are increasingly ubiquitous. However, the validity of such devices for sleep assessment has not been directly compared to alternatives such as wrist actigraphy or polysomnography (PSG).
Methods
Eight participants each completed four nights in a sleep laboratory, equipped with PSG and several wearable devices. Registered polysomnographic technologist-scored PSG served as ground truth for sleep–wake state. Wearable devices providing sleep–wake classification data were compared to PSG at both an epoch-by-epoch and night level. Data from multisensor wearables (Apple Watch and Oura Ring) were compared to data available from electrocardiography and a triaxial wrist actigraph to evaluate the quality and utility of heart rate and motion data. Machine learning methods were used to train and test sleep–wake classifiers, using data from consumer wearables. The quality of classifications derived from devices was compared.
Results
For epoch-by-epoch sleep–wake performance, research devices ranged in d′ between 1.771 and 1.874, with sensitivity between 0.912 and 0.982, and specificity between 0.366 and 0.647. Data from multisensor wearables were strongly correlated at an epoch-by-epoch level with reference data sources. Classifiers developed from the multisensor wearable data ranged in d′ between 1.827 and 2.347, with sensitivity between 0.883 and 0.977, and specificity between 0.407 and 0.821.
Conclusions
Data from multisensor consumer wearables are strongly correlated with reference devices at the epoch level and can be used to develop epoch-by-epoch models of sleep–wake rivaling existing research devices.
Cet article clarifie la nature des relations entre économie positive et économie normative standard. Dès lors que la rationalité peut être caractérisée par la satisfaction de conditions portant sur ...les choix et les préférences et qu’il est établit que les individus sont approximativement rationnels, il est possible pour les économistes d’utiliser la théorie de la rationalité pour expliquer les choix. S’il s’avère de plus que les individus sont, comme cela est souvent supposé en économie positive, essentiellement égoïstes et raisonnablement informés, alors leurs préférences peuvent être utilisées comme des indicateurs de leur niveau de bien-être. Par conséquent, la modélisation des choix et du bien-être en termes de préférences rationnelles permet d’unifier économie positive et économie normative. En expliquant les résultats du marché par le biais des choix individuels, en expliquant les choix par les préférences, et en supposant que les préférences sont des indicateurs du bien-être, les économistes s’intéressant aux problématiques relatives au bien-être peuvent ainsi développer une théorie normative reposant sur leur théorie positive. Cette approche standard de l’économie normative est confrontée à plusieurs difficultés, mais son unité et son lien avec l’économie positive la rendent également particulièrement attractive.
Multiple sclerosis (MS) is a disabling, chronic disease that imposes a significant economic burden on patients and the US healthcare system. The largest cost component for individuals with MS are ...prescription drugs, specifically disease-modifying therapies (DMTs). Despite an increase in the number and diversity of DMTs over the past 10 years, acquisition costs for all DMTs have escalated dramatically at rates substantially higher than medical inflation. Currently, costs for most DMTs exceed $70,000 a year. Recent cost-effectiveness studies suggest the cost for nearly all DMTs exceeds generally accepted thresholds for what is considered a good value in the USA, even after factoring expected rebates. The high cost of DMTs is symptomatic of systemic dysfunction in the pharmaceutical market. Strategies aimed at reigning in high-cost medications include proposals ranging from increasing pricing transparency to allowing Medicare to negotiate directly with manufacturers. Because the economics of pharmaceuticals are inherently complex, a diversity of approaches will be required.
•Perceived Social Isolation (loneliness) is health-relevant, not only in the elderly.•Stress-related hormones and neurotransmitters, are relevant in loneliness.•Desired solitude and perceived social ...isolation both correlate with negative health consequences.•Medical treatment for reducing stress may be effective in loneliness.•Screening and early intervention are clinical best options.
Perceived Social Isolation or loneliness, a cognitive state with negative effects on health, is a global problem.
Treatment of diagnosed loneliness is mostly through its physical (cardiovascular) and/or mental (depression, anxiety) health consequences, with limited success. Desired solitude is considered a means to wellbeing by Mindfulness-Based Stress Reduction (MBSR), Evidence exists for the relevancy of developing stress-related medical factors which have demonstrated a prodromic or causal role in loneliness, depression and hopelessness. Consequently, presently unexplored direct medical treatment of biological factors in loneliness becomes an option.
We searched medical and psychological databases including PubMed, PsycINFO and Cochrane from 1975 thru May 2018 with the keywords, no limits, pursuing related links. Studies identified: 373. Studies considered: 42.
Studies indicating causal and correlational links between stress and loneliness were considered as to relevancy and study quality.
Data indicate that both loneliness and solitude may be caused by or correlate with biological factors resulting from psychological (life quality) and medical (health) factors including circulating stress hormones, immune system components and the glutamate system.
Causal and correlational links between stress and loneliness are under-researched and study size is generally small. Most research is correlational and study criteria diverse. This review is partly descriptive.
Forty years of incidental research give indications as to a co-causal or prodromic role for stress in loneliness.
Early medical and psychological stress treatment should be combined for incipient and clinical loneliness.
By using synchrotron X-ray powder diffraction, the temperature dependent phase diagram of the hybrid perovskite tri-halide compounds, methyl ammonium lead iodide (MAPbI
, MA
= CH
NH
) and methyl ...ammonium lead bromide (MAPbBr
), as well as of their solid solutions, has been established. The existence of a large miscibility gap between 0.29 ≤
≤ 0.92 (±0.02) for the MAPb(I
Br
)
solid solution has been proven. A systematic study of the lattice parameters for the solid solution series at room temperature revealed distinct deviations from Vegard's law. Furthermore, temperature dependent measurements showed that a strong temperature dependency of lattice parameters from the composition is present for iodine rich compositions. In contrast, the bromine rich compositions show an unusually low dependency of the phase transition temperature from the degree of substitution.
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