We present a new observation‐based estimate of the global oceanic carbon dioxide (CO2) sink and its temporal variation on a monthly basis from 1998 through 2011 and at a spatial resolution of 1°×1°. ...This sink estimate rests upon a neural network‐based mapping of global surface ocean observations of the partial pressure of CO2 (pCO2) from the Surface Ocean CO2 Atlas database. The resulting pCO2 has small biases when evaluated against independent observations in the different ocean basins, but larger randomly distributed differences exist particularly in high latitudes. The seasonal climatology of our neural network‐based product agrees overall well with the Takahashi et al. (2009) climatology, although our product produces a stronger seasonal cycle at high latitudes. From our global pCO2 product, we compute a mean net global ocean (excluding the Arctic Ocean and coastal regions) CO2 uptake flux of −1.42 ± 0.53 Pg C yr−1, which is in good agreement with ocean inversion‐based estimates. Our data indicate a moderate level of interannual variability in the ocean carbon sink (±0.12 Pg C yr−1, 1σ) from 1998 through 2011, mostly originating from the equatorial Pacific Ocean, and associated with the El Niño–Southern Oscillation. Accounting for steady state riverine and Arctic Ocean carbon fluxes our estimate further implies a mean anthropogenic CO2 uptake of −1.99 ± 0.59 Pg C yr−1 over the analysis period. From this estimate plus the most recent estimates for fossil fuel emissions and atmospheric CO2 accumulation, we infer a mean global land sink of −2.82 ± 0.85 Pg C yr−1 over the 1998 through 2011 period with strong interannual variation.
Key Points
A new method permits us to upscale surface ocean pCO2 observationsWe find moderate variability in the global ocean carbon sinkENSO is the dominant mode driving the sink variability
The Atlantic Ocean is one of the most important sinks for atmospheric carbon dioxide (CO2), but this sink has been shown to vary substantially in time. Here we use surface ocean CO2 observations to ...estimate this sink and the temporal variability from 1998 through 2007 in the Atlantic Ocean. We benefit from (i) a continuous improvement of the observations, i.e. the Surface Ocean CO2 Atlas (SOCAT) v1.5 database and (ii) a newly developed technique to interpolate the observations in space and time. In particular, we use a two-step neural network approach to reconstruct basin-wide monthly maps of the sea surface partial pressure of CO2 (pCO2) at a resolution of 1° × 1°. From those, we compute the air–sea CO2 flux maps using a standard gas exchange parameterization and high-resolution wind speeds. The neural networks fit the observed pCO2 data with a root mean square error (RMSE) of about 10 μatm and with almost no bias. A check against independent time-series data and new data from SOCAT v2 reveals a larger RMSE of 22.8 μatm for the entire Atlantic Ocean, which decreases to 16.3 μatm for data south of 40° N. We estimate a decadal mean uptake flux of −0.45 ± 0.15 Pg C yr−1 for the Atlantic between 44° S and 79° N, representing the sum of a strong uptake north of 18° N (−0.39 ± 0.10 Pg C yr−1), outgassing in the tropics (18° S–18° N, 0.11 ± 0.07 Pg C yr−1), and uptake in the subtropical/temperate South Atlantic south of 18° S (−0.16 ± 0.06 Pg C yr−1), consistent with recent studies. The strongest seasonal variability of the CO2 flux occurs in the temperature-driven subtropical North Atlantic, with uptake in winter and outgassing in summer. The seasonal cycle is antiphased in the subpolar latitudes relative to the subtropics largely as a result of the biologically driven winter-to-summer drawdown of CO2. Over the 10 yr analysis period (1998 through 2007), sea surface pCO2 increased faster than that of the atmosphere in large areas poleward of 40° N, while in other regions of the North Atlantic the sea surface pCO2 increased at a slower rate, resulting in a barely changing Atlantic carbon sink north of the Equator (−0.01 ± 0.02 Pg C yr−1 decade−1). Surface ocean pCO2 increased at a slower rate relative to atmospheric CO2 over most of the Atlantic south of the Equator, leading to a substantial trend toward a stronger CO2 sink for the entire South Atlantic (−0.14 ± 0.02 Pg C yr−1 decade−1). In contrast to the 10 yr trends, the Atlantic Ocean carbon sink varies relatively little on inter-annual timescales (±0.04 Pg C yr−1; 1 σ).
Interannual anomalies in the sea-air carbon dioxide (CO2 ) exchange have been estimated from surface-ocean CO2 partial pressure measurements. Available data are sufficient to constrain these ...anomalies in large parts of the tropical and North Pacific and in the North Atlantic, in some areas covering the period from the mid 1980s to 2011. Global interannual variability is estimated as about 0.31 Pg C yr-1 (temporal standard deviation 1993-2008). The tropical Pacific accounts for a large fraction of this global variability, closely tied to El Niño-Southern Oscillation (ENSO). Anomalies occur more than 6 months later in the east than in the west. The estimated amplitude and ENSO response are roughly consistent with independent information from atmospheric oxygen data. This both supports the variability estimated from surface-ocean carbon data and demonstrates the potential of the atmospheric oxygen signal to constrain ocean biogeochemical processes. The ocean variability estimated from surface-ocean carbon data can be used to improve land CO2 flux estimates from atmospheric inversions.
Lack of physical activity causes bone loss and fractures not only in elderly people, but also in bedridden patients or otherwise inactive youth. This is fast becoming one of the most serious ...healthcare problems in the world. Osteocytes, cells buried within our bones, stimulate bone formation in the presence of mechanical stimuli, as well as bone degradation in the absence of such stimuli. As yet, we do not fully comprehend how osteocytes sense mechanical stimuli, and only know a fraction of the whole range of molecules that osteocytes subsequently produce to regulate bone formation and degradation in response to mechanical stimuli. This dramatically hampers the design of bone loss prevention strategies. In this review we will focus on the first step in the cascade of events leading to adaptation of bone mass to mechanical loading, i.e., on how osteocytes are able to perceive mechanical stimuli placed on whole bones. We will place particular emphasis on the role of the osteocyte cytoskeleton in mechanosensing. Given the crucial importance of osteocytes in maintaining a proper resistance against bone fracture, greater knowledge of the molecular mechanisms that govern the adaptive response of osteocytes to mechanical stimuli may lead to the development of new strategies towards fracture prevention and enhanced bone healing.
The hypothesis that elimination of facultative and strict anaerobic microorganisms from the gastro-intestinal tract by antimicrobial drugs in the period of time around allogeneic bone marrow ...transplantation (BMT) prevents acute graft-versus-host disease (GVHD), was examined in a cohort of 112 children grafted between 1989 and 2002 for hematological malignancies. All patients received T-cell replete marrow from human leukocyte antigens (HLA) matched sibling donors under identical transplantation conditions. To eliminate microorganisms from the gastro-intestinal tract, total gastro-intestinal decontamination (GID) was applied by high doses of non-absorbable antimicrobial drugs while the graft recipient was maintained in strict protective isolation. About half of the children (51%) proved to be successfully decontaminated, and about half (49%) unsuccessfully. One recipient got acute GVHD in the first group and 8 in the second group (p = 0.013). The degree of success of total GID was decisive for the occurrence of acute GVHD, irrespective of the presence of other risk factors such as higher age of recipient and/or donor, female donor for male recipient and carriership or reactivation of herpesviruses. Our results demonstrate that successful total GID of the graft recipient prevents moderate to severe acute GVHD. We suppose that substantial translocation of gastro-intestinal microorganisms or parts of these, functioning as microbial-associated molecular patterns (MAMP's), triggering macrophages/dendritic cells via pattern recognizing receptors (PRR's) is prohibited. As a consequence the initiation and progression of an inflammatory process leading to acute GVHD is inhibited.
The periodontal ligament (PDL) connects the tooth root and alveolar bone. It is an aligned fibrous network that is interposed between, and anchored to, both mineralized surfaces. Periodontal disease ...is common and reduces the ability of the PDL to act as a shock absorber, a barrier for pathogens and a sensor of mastication. Although disease progression can be stopped, current therapies do not primarily focus on tissue regeneration. Functional regeneration of PDL may be achieved using innovative techniques, such as tissue engineering. However, the complex fibrillar architecture of the PDL, essential to withstand high forces, makes PDL tissue engineering very challenging. This challenge may be met by studying PDL anatomy and development. Understanding PDL anatomy, development and maintenance provides clues regarding the specific events that need to be mimicked for the formation of this intricate tissue. Owing to the specific composition of the PDL, which develops by self‐organization, a different approach than the typical combination of biomaterials, growth factors and regenerative cells is necessary for functional PDL engineering. Most specifically, the architecture of the new PDL to be formed does not need to be dictated by textured biomaterials but can emerge from the local mechanical loading conditions. Elastic hydrogels are optimal to fill the space properly between tooth and bone, may house cells and growth factors to enhance regeneration and allow self‐optimization by the alignment to local stresses. We suggest that cells and materials should be placed in a proper mechanical environment to initiate a process of self‐organization resulting in a functional architecture of the PDL.
Aims
To investigate short‐ and long‐term effects of real‐time monitoring medication use combined with short message service (SMS) reminders for missed doses on refill adherence to oral anti‐diabetic ...medication.
Methods
A randomized controlled trial with two intervention groups and one control group involving 161 participants with Type 2 diabetes with suboptimal adherence. For 6 months, participants in the SMS group (n = 56) were monitored and received SMS reminders if they missed their medication. Participants in the non‐SMS group (n = 48) were only monitored. The control group (n = 57) was not exposed to any intervention. Primary outcome measure was refill adherence to oral anti‐diabetic medication. Multi‐level regression analyses were performed to examine intervention effects on adherence between and within groups after 1 and 2 years of follow‐up.
Results
At baseline, mean refill adherence was comparable between the groups. After 1 year, adherence in the SMS group was significantly higher than in the control group (79.5% vs. 64.5%; P < 0.001) and showed a significant improvement from baseline (+16.3%; P < 0.001). Mean adherence in the non‐SMS group reached 73.1% (+7.3%; P < 0.05), but did not differ from the control group (P = 0.06). After 2 years, the improved adherence in the SMS group persisted and remained significantly higher than in the control group (80.4% vs. 68.4%; P < .01), contrary to the non‐SMS group whose adherence approached baseline level again (65.5%).
Conclusions
This study shows the long‐term effectiveness of real‐time medication monitoring combined with SMS reminders in improving refill adherence. This new reminder system can strengthen the self‐management of people with diabetes.
What's new?
The innovative real‐time medication monitoring system evaluated in this study is the first to provide the opportunity to intervene only when patients forget to take their medication.
This study showed that receiving short message service (SMS) reminders only when a dose is missed results in a higher refill adherence, and is the first to demonstrate long‐term effectiveness of electronic reminders on adherence.
The real‐time medication monitoring reminder system can especially provide support for people who have problems taking their medication because of forgetfulness.
This system can also strengthen a person's self‐management, as medication management is an important aspect of self‐management.
Carbon dioxide (CO2) is, next to water vapour, considered to be the most important natural greenhouse gas on Earth. Rapidly rising atmospheric CO2 concentrations caused by human actions such as ...fossil fuel burning, land-use change or cement production over the past 250 years have given cause for concern that changes in Earth's climate system may progress at a much faster pace and larger extent than during the past 20 000 years. Investigating global carbon cycle pathways and finding suitable adaptation and mitigation strategies has, therefore, become of major concern in many research fields. The oceans have a key role in regulating atmospheric CO2 concentrations and currently take up about 25% of annual anthropogenic carbon emissions to the atmosphere. Questions that yet need to be answered are what the carbon uptake kinetics of the oceans will be in the future and how the increase in oceanic carbon inventory will affect its ecosystems and their services. This requires comprehensive investigations, including high-quality ocean carbon measurements on different spatial and temporal scales, the management of data in sophisticated databases, the application of Earth system models to provide future projections for given emission scenarios as well as a global synthesis and outreach to policy makers. In this paper, the current understanding of the ocean as an important carbon sink is reviewed with respect to these topics. Emphasis is placed on the complex interplay of different physical, chemical and biological processes that yield both positive and negative air–sea flux values for natural and anthropogenic CO2 as well as on increased CO2 (uptake) as the regulating force of the radiative warming of the atmosphere and the gradual acidification of the oceans. Major future ocean carbon challenges in the fields of ocean observations, modelling and process research as well as the relevance of other biogeochemical cycles and greenhouse gases are discussed.
Highlights ► Real Time Medication Monitoring provides detailed and accurate data on patients’ medication use. ► SMS reminders sent only if patients forget medication improve adherence to oral ...antidiabetics. ► SMS reminders are appreciated by patients. ► Real Time Medication Monitoring with SMS reminders provide opportunities for other patient groups as well.