Warming experiments are increasingly relied on to estimate plant responses to global climate change. For experiments to provide meaningful predictions of future responses, they should reflect the ...empirical record of responses to temperature variability and recent warming, including advances in the timing of flowering and leafing. We compared phenology (the timing of recurring life history events) in observational studies and warming experiments spanning four continents and 1,634 plant species using a common measure of temperature sensitivity (change in days per degree Celsius). We show that warming experiments underpredict advances in the timing of flowering and leafing by 8.5-fold and 4.0-fold, respectively, compared with long-term observations. For species that were common to both study types, the experimental results did not match the observational data in sign or magnitude. The observational data also showed that species that flower earliest in the spring have the highest temperature sensitivities, but this trend was not reflected in the experimental data. These significant mismatches seem to be unrelated to the study length or to the degree of manipulated warming in experiments. The discrepancy between experiments and observations, however, could arise from complex interactions among multiple drivers in the observational data, or it could arise from remediable artefacts in the experiments that result in lower irradiance and drier soils, thus dampening the phenological responses to manipulated warming. Our results introduce uncertainty into ecosystem models that are informed solely by experiments and suggest that responses to climate change that are predicted using such models should be re-evaluated.
Committing to ecological restoration Suding, Katharine; Higgs, Eric; Palmer, Margaret ...
Science,
05/2015, Volume:
348, Issue:
6235
Journal Article
Peer reviewed
Open access
At the September 2014 United Nations Climate Summit, governments rallied around an international agreement-the New York Declaration on Forests-that underscored restoration of degraded ecosystems as ...an auspicious solution to climate change. Ethiopia committed to restore more than one-sixth of its land. Uganda, the Democratic Republic of Congo, Guatemala, and Colombia pledged to restore huge areas within their borders. In total, parties committed to restore a staggering 350 million hectares by 2030.
Earth and its magnetosphere are immersed in the supersonic flow of the solar-wind plasma that fills interplanetary space. As the solar wind slows and deflects to flow around Earth, or any other ...obstacle, a 'bow shock' forms within the flow. Under almost all solar-wind conditions, planetary bow shocks such as Earth's are collisionless, supercritical shocks, meaning that they reflect and accelerate a fraction of the incident solar-wind ions as an energy dissipation mechanism
, which results in the formation of a region called the ion foreshock
. In the foreshock, large-scale, transient phenomena can develop, such as 'hot flow anomalies'
, which are concentrations of shock-reflected, suprathermal ions that are channelled and accumulated along certain structures in the upstream magnetic field. Hot flow anomalies evolve explosively, often resulting in the formation of new shocks along their upstream edges
, and potentially contribute to particle acceleration
, but there have hitherto been no observations to constrain this acceleration or to confirm the underlying mechanism. Here we report observations of a hot flow anomaly accelerating solar-wind ions from roughly 1-10 kiloelectronvolts up to almost 1,000 kiloelectronvolts. The acceleration mechanism depends on the mass and charge state of the ions and is consistent with first-order Fermi acceleration
. The acceleration that we observe results from only the interaction of Earth's bow shock with the solar wind, but produces a much, much larger number of energetic particles compared to what would typically be produced in the foreshock from acceleration at the bow shock. Such autogenous and efficient acceleration at quasi-parallel bow shocks (the normal direction of which are within about 45 degrees of the interplanetary magnetic field direction) provides a potential solution to Fermi's 'injection problem', which requires an as-yet-unexplained seed population of energetic particles, and implies that foreshock transients may be important in the generation of cosmic rays at astrophysical shocks throughout the cosmos.
Pharmacokinetic and pharmacodynamic changes occur with increasing age. Sex differences in pharmacokinetics and pharmacodynamics exist and persist at older age. The issue for the clinician is how to ...best treat the older patient with currently available knowledge. This communication highlights age‐ and sex‐related differences in pharmacokinetics that should influence clinical practice and prescribing guidelines to optimize clinical responses. The most compelling data for sex‐specific medication dosing guidelines for older patients are related to volume of distribution differences, or size differences, between the sexes and to differences in glomerular filtration rates.
Clinical Pharmacology & Therapeutics (2007) 82, 87–96. doi:10.1038/sj.clpt.6100226; published online 9 May 2007
An excessive amount of adipose tissue may contribute to sarcopenia and may be one mechanism underlying accelerated loss of muscle mass and strength with aging. We therefore examined the association ...of baseline total body fat with changes in leg lean mass, muscle strength, and muscle quality over 7 years of follow-up and whether this link was explained by adipocytokines and insulin resistance.
Data were from 2,307 men and women, aged 70-79 years, participating in the Health, Aging, and Body Composition study. Total fat mass was acquired from dual energy X-ray absorptiometry. Leg lean mass was assessed by dual energy X-ray absorptiometry in Years 1, 2, 3, 4, 5, 6, and 8. Knee extension strength was measured by isokinetic dynamometer in Years 1, 2, 4, 6, and 8. Muscle quality was calculated as muscle strength divided by leg lean mass.
Every SD greater fat mass was related to 1.3 kg more leg lean mass at baseline in men and 1.5 kg in women (p < .01). Greater fat mass was also associated with a greater decline in leg lean mass in both men and women (0.02 kg/year, p < .01), which was not explained by higher levels of adipocytokines and insulin resistance. Larger fat mass was related to significantly greater muscle strength but significantly lower muscle quality at baseline (p < .01). No significant differences in decline of muscle strength and quality were found.
High fatness was associated with lower muscle quality, and it predicts accelerated loss of lean mass. Prevention of greater fatness in old age may decrease the loss of lean mass and maintain muscle quality and thereby reducing disability and mobility impairments.
Objective
There are limited data on combinations of co-morbid conditions to guide efforts to improve therapeutic strategies in patients with multiple co-morbid conditions. To some extent, this may be ...due to limited data on combinations of co-morbid conditions in patient groups. Our goal was to determine the most common comorbid medical conditions in older residents of U. S. nursing homes and identify sex differences in prevalences and changes across the agespan of nursing residents.
Design
Cross sectional analysis of National Nursing Home Survey (NNHS) —a nationally representative sample with comprehensive medical data on nursing home residents.
Setting
1174 Nursing homes.
Participants
Long term stay residents of U.S. Nursing Homes aged 65 years and older (11,734: 8745 women, 2989 men).
Measurements
Determination of the prevalences of the most frequent two and three disease combinations identified using Clinical Classifications Software (CCS) for ICD-9-CM and a composite vascular disease diagnosis (atherosclerosis and/or coronary artery disease, and/or peripheral arterial disease, and/or cerebrovascular disease or stroke) from the most recent and only NNHS survey with comprehensive medical diagnosis information.
Results
Frequent 2-disease combinations were: hypertension (HTN) + dementia (DEM) in 27%, HTN + any Vascular (Vasc) disease (26%), HTN + depression(DEP) 21%, HTN + arthritis(ARTH) 20%, DEM + Vasc (21%), DEM+Depression 19%, Arthritis + DEM 17%, DEP + Vasc (16%), ARTH + Vasc (15%), followed by HTN + GERD (14%) and ARTH + DEP (14%). Frequent 3-disease combinations: HTN +VASC+ DEP in 13%, HTN +DEM +DEP (11%), and HTN+Arthritis+DEM (10%). HTN was in 80% of the top 3-disease combinations, Vasc in 50%, HTN+VASC in 35%, DEM or DEP in 40%, ARTH in 25% and GERD in 20%. Combinations with anemia, arthritis, dementia, heart failure, osteroporosis, thyroid disease were higher in women, COPD combinations higher in men. As age increased, dementia, depression, arthritis, and anemia with hypertension were common co-morbid combinations, diabetes and heart failure were not.
Conclusions
Hypertension, vascular disease, dementia, arthritis, depression, and gastroesophageal reflux disease were part of the most prevalent co-morbid conditions. Multimorbidity patterns can be identified in nursing home residents and vary with age and by sex.
Objective:
Our goal was to compare direct quantitation of circulating free 25-hydroxyvitamin D (25(OH)D)levels to calculated free 25(OH)D levels and their relationships to intact PTH (iPTH), a ...biomarker of 25(OH)D effect, in humans with a range of clinical conditions.
Patients and Methods:
Serum samples and clinical data were collected from 155 people: 111 without cirrhosis or pregnancy (comparison group), 24 cirrhotic patients with albumin <2.9 g/dL, and 20 pregnant women (second and third trimester). Total 25(OH)D (LC/MS/MS), free 25(OH)D (immunoassay), vitamin D binding protein (DBP) (immunoassay), albumin, and iPTH (immunoassay) were measured.
Results:
Total 25(OH)D, DBP, and albumin were lowest in patients with cirrhosis, but measured free 25(OH)D was highest in this group (P < .001). DBP was highest in pregnant women (P < .001), but measured free 25(OH)D did not differ from the comparison group. Calculated free 25(OH)D was positively correlated with measured free 25(OH)D (P < .0001) but explained only 13% of the variability with calculated values higher than measured. African Americans had lower DBP than other ethnic populations within all clinical groups (P < .03), and differences between measured and calculated free 25(OH)D were greatest in African Americans (P < .001). Measured free 25(OH)D was correlated with total 25(OH)D (P < .0001; r2 = 0.51), but calculated free 25(OH)D was not. Similarly, both measured free 25(OH)D (P < .02) and total 25(OH)D (P < .05) were correlated with iPTH, but calculated free 25(OH)D was not.
Conclusions:
Calculated free 25(OH)D levels varied considerably from direct measurements of free 25(OH)D with discrepancies greatest in the data for African Americans. Differences in DBP binding affinity likely contributed to estimation errors between the races. Directly measured free 25(OH)D concentrations were related to iPTH, but calculated estimates were not. Current algorithms to calculate free 25(OH)D may not be accurate. Further evaluation of directly measured free 25(OH)D levels to determine its role in research and clinical management of patients is needed.
The objective of this study was to determine vitamin D supplementation effects on concentrations of atorvastatin and cholesterol in patients. Sixteen patients (8 men, 8 women; 10 Caucasians, 4 ...African Americans, 1 Hispanic, 1 Asian), aged 63 ± 11 years (mean ± SD, weight 92 ± 31 kg) on atorvastatin (45 ± 33 mg/day) were studied with and without supplemental vitamin D (800 IU/day for 6 weeks). Levels of vitamin D (1,25‐dihydroxy(OH) and 25 OH‐metabolites), atorvastatin (parent, OH‐acid metabolites, lactone, and lactone metabolites), and cholesterol (total, low‐density lipoprotein (LDL) cholesterol, and high‐density lipoprotein (HDL) cholesterol) were determined at 0.5, 3, and 10 h after dosing. Vitamin D supplementation increased vitamin D‐25‐OH metabolites (P < 0.0001) without increased 1,25‐dihydroxy vitamin D. Atorvastatin and active metabolite concentrations (P < 0.001) as well as LDL‐cholesterol and total‐cholesterol levels (97 ± 28 mg/dl vs. 83 ± 30 and 169 ± 35 mg/dl vs. 157 ± 37, P < 0.005) were lower during vitamin D supplementation. The conclusion of the study is that vitamin D supplementation lowers atorvastatin and active metabolite concentrations yet has synergistic effects on cholesterol concentrations.
Clinical Pharmacology & Therapeutics (2009); 85, 2, 198–203 doi:10.1038/clpt.2008.165
Phylogenetic conservatism in plant phenology Davies, T. Jonathan; Wolkovich, Elizabeth M.; Kraft, Nathan J. B. ...
The Journal of ecology,
November 2013, Volume:
101, Issue:
6
Journal Article
Peer reviewed
Open access
1. Phenological events - defined points in the life cycle of a plant or animal - have been regarded as highly plastic traits, reflecting flexible responses to various environmental cues. 2. The ...ability of a species to track, via shifts in phenological events, the abiotic environment through time might dictate its vulnerability to future climate change. Understanding the predictors and drivers of phenological change is therefore critical. 3. Here, we evaluated evidence for phylogenetic conservatism - the tendency for closely related species to share similar ecological and biological attributes - in phenological traits across flowering plants. We aggregated published and unpublished data on timing of first flower and first leaf, encompassing ~4000 species at 23 sites across the Northern Hemisphere. We reconstructed the phylogeny for the set of included species, first, using the software program Phylomatic, and second, from DNA data. We then quantified phylogenetic conservatism in plant phenology within and across sites. 4. We show that more closely related species tend to flower and leaf at similar times. By contrasting mean flowering times within and across sites, however, we illustrate that it is not the time of year that is conserved, but rather the phenological responses to a common set of abiotic cues. 5. Our findings suggest that species cannot be treated as statistically independent when modelling phenological responses. 6. Synthesis. Closely related species tend to resemble each other in the timing of their life-history events, a likely product of evolutionarily conserved responses to environmental cues. The search for the underlying drivers of phenology must therefore account for species' shared evolutionary histories.
Abstract
STUDY QUESTION
What is an objective approach that employs measurable and reproducible physiologic changes as the basis for the classification of ovarian hyperstimulation syndrome (OHSS) in ...order to facilitate more accurate reporting of incidence rates within and across clinical trials?
SUMMARY ANSWER
The OHSS flow diagram is an objective approach that will facilitate consistent capture, classification and reporting of OHSS within and across clinical trials.
WHAT IS KNOWN ALREADY
OHSS is a potentially life-threatening iatrogenic complication of the early luteal phase and/or early pregnancy after ovulation induction (OI) or ovarian stimulation (OS). The clinical picture of OHSS (the constellation of symptoms associated with each stage of the disease) is highly variable, hampering its appropriate classification in clinical trials. Although some degree of ovarian hyperstimulation is normal after stimulation, the point at which symptoms transition from those anticipated to those of a disease state is nebulous.
STUDY DESIGN, SIZE, DURATION
An OHSS working group, comprised of subject matter experts and clinical researchers who have significantly contributed to the field of fertility, was convened in April and November 2014.
PARTICIPANTS/MATERIALS, SETTING, METHODS
The OHSS working group was tasked with reaching a consensus on the definition and the classification of OHSS for reporting in clinical trials. The group engaged in targeted discussion regarding the scientific background of OHSS, the criteria proposed for the definition and the rationale for universal adoption. An agreement was reached after discussion with all members.
MAIN RESULTS AND THE ROLE OF CHANCE
One of the following conditions must be met prior to making the diagnosis of OHSS in the context of a clinical trial: (i) the subject has undergone OS (either controlled OS or OI) AND has received a trigger shot for final oocyte maturation (e.g. hCG, GnRH agonist GnRHa or kisspeptin) followed by either fresh transfer or segmentation (cryopreservation of embryos) or (ii) the subject has undergone OS or OI AND has a positive pregnancy test. All study patients who develop symptoms of OHSS should undergo a thorough examination. An OHSS flow diagram was designed to be implemented for all subjects with pelvic or abdominal complaints, such as lower abdominal discomfort or distention, nausea, vomiting and diarrhea, and/or for subjects suspected of having OHSS. The diagnosis of OHSS should be based on the flow diagram.
LIMITATIONS, REASONS FOR CAUTION
This classification system is primarily intended to address the needs of the clinical investigator undertaking clinical trials in the field of OS and may not be applicable for the use in clinical practice or with OHSS occurring under natural circumstances.
WIDER IMPLICATIONS OF THE FINDINGS
The proposed OHSS classification system will enable an accurate estimate of the incidence and severity of OHSS within and across clinical trials performed in women with infertility.
STUDY FUNDING/COMPETING INTERESTS
Financial support for the advisory group meetings was provided by Merck & Co., Inc., Kenilworth, NJ, USA. P.H. reports unrestricted research grants from MSD, Merck and Ferring, and honoraria for lectures from MSD, Merck and IBSA. S.M.N. reports that he has received fees and grant support from the following companies (in alphabetic order): Beckman Coulter, Besins, EMD Serono, Ferring Pharmaceuticals, Finox, MSD and Roche Diagnostics over the previous 5 years. P.D., C.C.C., J.L.F., H.M.F., and P.L. report no relationships that present a potential conflict of interest. B.C.T. reports: grants and honorarium from Merck Serono; unrestricted research grants, travel grants and honorarium, and participation in a company-sponsored speaker's bureau from Merck Sharp & Dohme; grants, travel grants, honoraria and advisory board membership from IBSA; travel grants from Ferring; and advisory board membership from Ovascience. L.B.S. reports current employment with Merck & Co, Inc., Kenilworth, NJ, USA, and owns stock in the company. K.G. and B.J.S. report prior employment with Merck & Co., Inc., Kenilworth, NJ, USA, and own stock in the company. All reported that competing interests are outside the submitted work. No other relationships or activities exist that could appear to have influenced the submitted work.
TRIAL REGISTRATION NUMBER
Not applicable.
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