Institution
University of Groningen
Education•Groningen, Groningen, Netherlands•
About: University of Groningen is a education organization based out in Groningen, Groningen, Netherlands. It is known for research contribution in the topics: Population & Poison control. The organization has 36346 authors who have published 69116 publications receiving 2940370 citations. The organization is also known as: Rijksuniversiteit Groningen & RUG.
Papers published on a yearly basis
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TL;DR: In this article, the authors report repetitive, monodirectional rotation around a central carbon-carbon double bond in a chiral, helical alkene, with each 360° rotation involving four discrete isomerization steps activated by ultraviolet light or a change in the temperature of the system.
Abstract: Attempts to fabricate mechanical devices on the molecular level1,2 have yielded analogues of rotors3, gears4, switches5, shuttles6,7, turnstiles8 and ratchets9. Molecular motors, however, have not yet been made, even though they are common in biological systems10. Rotary motion as such has been induced in interlocked systems11,12,13 and directly visualized for single molecules14, but the controlled conversion of energy into unidirectional rotary motion has remained difficult to achieve. Here we report repetitive, monodirectional rotation around a central carbon–carbon double bond in a chiral, helical alkene, with each 360° rotation involving four discrete isomerization steps activated by ultraviolet light or a change in the temperature of the system. We find that axial chirality and the presence of two chiral centres are essential for the observed monodirectional behaviour of the molecular motor. Two light-induced cis-trans isomerizations are each associated with a 180° rotation around the carbon–carbon double bond and are each followed by thermally controlled helicity inversions, which effectively block reverse rotation and thus ensure that the four individual steps add up to one full rotation in one direction only. As the energy barriers of the helicity inversion steps can be adjusted by structural modifications, chiral alkenes based on our system may find use as basic components for ‘molecular machinery’ driven by light.
1,494 citations
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University of British Columbia1, University of Vermont2, University of Manitoba3, University of Wyoming4, Temple University5, University of North Carolina at Chapel Hill6, National University of Distance Education7, Dalhousie University8, State University of New York System9, City University of New York10, Boston University11, University of Groningen12, University of Savoy13, National Autonomous University of Mexico14
TL;DR: The authors developed an 18-item measure, the ASI-3, which assesses the 3 factors best replicated in previous research: Physical, Cognitive, and Social Concerns and displayed generally good performance on other indices of reliability and validity, along with evidence of improved psychometric properties over the original ASI.
Abstract: Accumulating evidence suggests that anxiety sensitivity (fear of arousal-related sensations) plays an important role in many clinical conditions, particularly anxiety disorders. Research has increasingly focused on how the basic dimensions of anxiety sensitivity are related to various forms of psychopathology. Such work has been hampered because the original measure--the Anxiety Sensitivity Index (ASI)--was not designed to be multidimensional. Subsequently developed multidimensional measures have unstable factor structures or measure only a subset of the most widely replicated factors. Therefore, the authors developed, via factor analysis of responses from U.S. and Canadian nonclinical participants (n=2,361), an 18-item measure, the ASI-3, which assesses the 3 factors best replicated in previous research: Physical, Cognitive, and Social Concerns. Factorial validity of the ASI-3 was supported by confirmatory factor analyses of 6 replication samples, including nonclinical samples from the United States and Canada, France, Mexico, the Netherlands, and Spain (n=4,494) and a clinical sample from the United States and Canada (n=390). The ASI-3 displayed generally good performance on other indices of reliability and validity, along with evidence of improved psychometric properties over the original ASI.
1,461 citations
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University of East Anglia1, University of Exeter2, Alfred Wegener Institute for Polar and Marine Research3, Ludwig Maximilian University of Munich4, Max Planck Society5, Commonwealth Scientific and Industrial Research Organisation6, Karlsruhe Institute of Technology7, Atlantic Oceanographic and Meteorological Laboratory8, Cooperative Institute for Marine and Atmospheric Studies9, École Normale Supérieure10, Centre national de la recherche scientifique11, University of Maryland, College Park12, University of Virginia13, Flanders Marine Institute14, Oak Ridge National Laboratory15, Woods Hole Research Center16, University of Illinois at Urbana–Champaign17, Geophysical Institute, University of Bergen18, Met Office19, University of California, San Diego20, Utrecht University21, Netherlands Environmental Assessment Agency22, University of Paris23, Oeschger Centre for Climate Change Research24, Tsinghua University25, National Center for Atmospheric Research26, Institute of Arctic and Alpine Research27, National Institute for Environmental Studies28, Cooperative Research Centre29, Hobart Corporation30, Japan Agency for Marine-Earth Science and Technology31, Wageningen University and Research Centre32, University of Groningen33, Bjerknes Centre for Climate Research34, Goddard Space Flight Center35, Leibniz Institute for Baltic Sea Research36, Princeton University37, Leibniz Institute of Marine Sciences38, National Oceanic and Atmospheric Administration39, Auburn University40, Food and Agriculture Organization41, VU University Amsterdam42
TL;DR: In this article, the authors describe data sets and methodology to quantify the five major components of the global carbon budget and their uncertainties, including emissions from land use and land-use change data and bookkeeping models.
Abstract: . Accurate assessment of anthropogenic carbon dioxide
( CO2 ) emissions and their redistribution among the atmosphere,
ocean, and terrestrial biosphere – the “global carbon budget” – is
important to better understand the global carbon cycle, support the
development of climate policies, and project future climate change. Here we
describe data sets and methodology to quantify the five major components of
the global carbon budget and their uncertainties. Fossil CO2
emissions ( EFF ) are based on energy statistics and cement
production data, while emissions from land use and land-use change ( ELUC ),
mainly deforestation, are based on land use and land-use change data and
bookkeeping models. Atmospheric CO2 concentration is measured
directly and its growth rate ( GATM ) is computed from the annual
changes in concentration. The ocean CO2 sink ( SOCEAN )
and terrestrial CO2 sink ( SLAND ) are estimated with
global process models constrained by observations. The resulting carbon
budget imbalance ( BIM ), the difference between the estimated
total emissions and the estimated changes in the atmosphere, ocean, and
terrestrial biosphere, is a measure of imperfect data and understanding of
the contemporary carbon cycle. All uncertainties are reported as ±1σ . For the last decade available (2008–2017), EFF was
9.4±0.5 GtC yr −1 , ELUC 1.5±0.7 GtC yr −1 , GATM 4.7±0.02 GtC yr −1 ,
SOCEAN 2.4±0.5 GtC yr −1 , and SLAND 3.2±0.8 GtC yr −1 , with a budget imbalance BIM of
0.5 GtC yr −1 indicating overestimated emissions and/or underestimated
sinks. For the year 2017 alone, the growth in EFF was about 1.6 %
and emissions increased to 9.9±0.5 GtC yr −1 . Also for 2017,
ELUC was 1.4±0.7 GtC yr −1 , GATM was 4.6±0.2 GtC yr −1 , SOCEAN was 2.5±0.5 GtC yr −1 , and SLAND was 3.8±0.8 GtC yr −1 ,
with a BIM of 0.3 GtC. The global atmospheric
CO2 concentration reached 405.0±0.1 ppm averaged over 2017.
For 2018, preliminary data for the first 6–9 months indicate a renewed
growth in EFF of + 2.7 % (range of 1.8 % to 3.7 %) based
on national emission projections for China, the US, the EU, and India and
projections of gross domestic product corrected for recent changes in the
carbon intensity of the economy for the rest of the world. The analysis
presented here shows that the mean and trend in the five components of the
global carbon budget are consistently estimated over the period of 1959–2017,
but discrepancies of up to 1 GtC yr −1 persist for the representation
of semi-decadal variability in CO2 fluxes. A detailed comparison
among individual estimates and the introduction of a broad range of
observations show (1) no consensus in the mean and trend in land-use change
emissions, (2) a persistent low agreement among the different methods on
the magnitude of the land CO2 flux in the northern extra-tropics,
and (3) an apparent underestimation of the CO2 variability by ocean
models, originating outside the tropics. This living data update documents
changes in the methods and data sets used in this new global carbon budget
and the progress in understanding the global carbon cycle compared with
previous publications of this data set (Le Quere et al., 2018, 2016,
2015a, b, 2014, 2013). All results presented here can be downloaded from
https://doi.org/10.18160/GCP-2018 .
1,458 citations
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TL;DR: An estimate of the effect of obesity and overweight in adulthood on life expectancy is provided, implicitly taking into account the various possible weight trajectories throughout the life course, based on data from the Framingham Heart Study.
Abstract: BACKGROUND: Overweight and obesity in adulthood are linked to an increased
risk for death and disease. Their potential effect on life expectancy and
premature death has not yet been described. OBJECTIVE: To analyze
reductions in life expectancy and increases in premature death associated
with overweight and obesity at 40 years of age. DESIGN: Prospective cohort
study. SETTING: The Framingham Heart Study with follow-up from 1948 to
1990. PARTICIPANTS: 3457 Framingham Heart Study participants who were 30
to 49 years of age at baseline. MEASUREMENTS: Mortality rates specific for
age and body mass index group (normal weight, overweight, or obese at
baseline) were derived within sex and smoking status strata. Life
expectancy and the probability of death before 70 years of age were
analyzed by using life tables. RESULTS: Large decreases in life expectancy
were associated with overweight and obesity. Forty-year-old female
nonsmokers lost 3.3 years and 40-year-old male nonsmokers lost 3.1 years
of life expectancy because of overweight. Forty-year-old female nonsmokers
lost 7.1 years and 40-year-old male nonsmokers lost 5.8 years because of
obesity. Obese female smokers lost 7.2 years and obese male smokers lost
6.7 years of life expectancy compared with normal-weight smokers. Obese
female smokers lost 13.3 years and obese male smokers lost 13.7 years
compared with normal-weight nonsmokers. Body mass index at ages 30 to 49
years predicted mortality after ages 50 to 69 years, even after adjustment
for body mass index at age 50 to 69 years. CONCLUSIONS: Obesity and
overweight in adulthood are associated with large decreases in life
expectancy and increases in early mortality. These decreases are similar
to those seen with smoking. Obesity in adulthood is a powerful predictor
of death at older ages. Because of the increasing prevalence of obesity,
more efficient prevention and treatment should become high priorities in
public health.
1,450 citations
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TL;DR: In this paper, the main contributions of microscopic consideration can offer are (1) the understanding and interpretation of experimental results, (2) semiquantitative estimates of experimental result, and (3) the capability to interpolate or extrapolate experimental data into regions that are only difficultly accessible in the laboratory.
Abstract: During recent decades it has become feasible to simulate the dynamics of molecular systems on a computer. The method of molecular dynamics (MD) solves Newton's equations of motion for a molecular system, which results in trajectories for all atoms in the system. From these atomic trajectories a variety of properties can be calculated. The aim of computer simulations of molecular systems is to compute macroscopic behavior from microscopic interactions. The main contributions a microscopic consideration can offer are (1) the understanding and (2) interpretation of experimental results, (3) semiquantitative estimates of experimental results, and (4) the capability to interpolate or extrapolate experimental data into regions that are only difficultly accessible in the laboratory. One of the two basic problems in the field of molecular modeling and simulation is how to efficiently search the vast configuration space which is spanned by all possible molecular conformations for the global low (free) energy regions which will be populated by a molecular system in thermal equilibrium. The other basic problem is the derivation of a sufficiently accurate interaction energy function or force field for the molecular system of interest. An important part of the art of computer simulation is to choose the unavoidable assumptions, approximations and simplifications of the molecular model and computational procedure such that their contributions to the overall inaccuracy are of comparable size, without affecting significantly the property of interest. Methodology and some practical applications of computer simulation in the field of (bio)chemistry will be reviewed.
1,443 citations
Authors
Showing all 36692 results
Name | H-index | Papers | Citations |
---|---|---|---|
Ronald C. Kessler | 274 | 1332 | 328983 |
Nicholas J. Wareham | 212 | 1657 | 204896 |
André G. Uitterlinden | 199 | 1229 | 156747 |
Lei Jiang | 170 | 2244 | 135205 |
Brenda W.J.H. Penninx | 170 | 1139 | 119082 |
Richard H. Friend | 169 | 1182 | 140032 |
Panos Deloukas | 162 | 410 | 154018 |
Jerome I. Rotter | 156 | 1071 | 116296 |
Christopher M. Dobson | 150 | 1008 | 105475 |
Dirk Inzé | 149 | 647 | 74468 |
Scott T. Weiss | 147 | 1025 | 74742 |
Dieter Lutz | 139 | 671 | 67414 |
Wilmar B. Schaufeli | 137 | 513 | 95718 |
Cisca Wijmenga | 136 | 668 | 86572 |
Arnold B. Bakker | 135 | 506 | 103778 |