Trajectories of the Earth System in the Anthropocene Steffen, Will; Rockström, Johan; Richardson, Katherine ...
Proceedings of the National Academy of Sciences - PNAS,
08/2018, Letnik:
115, Številka:
33
Journal Article
Recenzirano
Odprti dostop
We explore the risk that self-reinforcing feedbacks could push the Earth System toward a planetary threshold that, if crossed, could prevent stabilization of the climate at intermediate temperature ...rises and cause continued warming on a “Hothouse Earth” pathway even as human emissions are reduced. Crossing the threshold would lead to a much higher global average temperature than any interglacial in the past 1.2 million years and to sea levels significantly higher than at any time in the Holocene. We examine the evidence that such a threshold might exist and where it might be. If the threshold is crossed, the resulting trajectory would likely cause serious disruptions to ecosystems, society, and economies. Collective human action is required to steer the Earth System away from a potential threshold and stabilize it in a habitable interglacial-like state. Such action entails stewardship of the entire Earth System—biosphere, climate, and societies—and could include decarbonization of the global economy, enhancement of biosphere carbon sinks, behavioral changes, technological innovations, new governance arrangements, and transformed social values.
To evaluate associations between the electronic environment, clerical burden, and burnout in US physicians.
Physicians across all specialties in the United States were surveyed between August and ...October 2014. Physicians provided information regarding use of electronic health records (EHRs), computerized physician order entry (CPOE), and electronic patient portals. Burnout was measured using validated metrics.
Of 6375 responding physicians in active practice, 5389 (84.5%) reported that they used EHRs. Of 5892 physicians who indicated that CPOE was relevant to their specialty, 4858 (82.5%) reported using CPOE. Physicians who used EHRs and CPOE had lower satisfaction with the amount of time spent on clerical tasks and higher rates of burnout on univariate analysis. On multivariable analysis, physicians who used EHRs (odds ratio OR=0.67; 95% CI, 0.57-0.79; P<.001) or CPOE (OR=0.72; 95% CI, 0.62-0.84; P<.001) were less likely to be satisfied with the amount of time spent on clerical tasks after adjusting for age, sex, specialty, practice setting, and hours worked per week. Use of CPOE was also associated with a higher risk of burnout after adjusting for these same factors (OR=1.29; 95% CI, 1.12-1.48; P<.001). Use of EHRs was not associated with burnout in adjusted models controlling for CPOE and other factors.
In this large national study, physicians' satisfaction with their EHRs and CPOE was generally low. Physicians who used EHRs and CPOE were less satisfied with the amount of time spent on clerical tasks and were at higher risk for professional burnout.
Simple Scaling of Catastrophic Landslide Dynamics Ekström, Göran; Stark, Colin P.
Science (American Association for the Advancement of Science),
03/2013, Letnik:
339, Številka:
6126
Journal Article
Recenzirano
Odprti dostop
Catastrophic landslides involve the acceleration and deceleration of millions of tons of rock and debris in response to the forces of gravity and dissipation. Their unpredictability and frequent ...location in remote areas have made observations of their dynamics rare. Through real-time detection and inverse modeling of teleseismic data, we show that landslide dynamics are primarily determined by the length scale of the source mass. When combined with geometric constraints from satellite imagery, the seísmically determined landslide force histories yield estimates of landslide duration, momenta, potential energy loss, mass, and runout trajectory. Measurements of these dynamical properties for 29 teleseismogenic landslides are consistent with a simple acceleration model in which height drop and rupture depth scale with the length of the failing slope.
Depending on the adequacy of collateral sources of blood flow, arterial stenosis or occlusion may lead to reduced perfusion pressure and ultimately reduced blood flow in the distal territory supplied ...by that vessel. There are two well-defined compensatory mechanisms to reduced pressure or flow – autoregulatory vasodilation and increased oxygen extraction fraction. Other changes, such as metabolic downregulation, are likely. The positive identification of autoregulatory vasodilation and increased oxygen extraction fraction in humans is an established risk factor for future ischemic stroke in some disease states such as atherosclerotic carotid stenosis and occlusion. The mechanisms by which ischemic stroke may occur are not clear, and may include an increased vulnerability to embolic events. The use of hemodynamic assessment to identify patients with occlusive vasculopathy at an increased risk for stroke is very appealing for several different patient populations, such as those with symptomatic intracranial atherosclerotic disease, moyamoya phenomenon, complete internal carotid artery occlusion, and asymptomatic cervical carotid artery stenosis. While there is very good data for stroke risk prediction in some of these groups, no intervention based on these tools has been proven effective yet. In this manuscript, we will review these topics above and identify areas for future research.
Addressing Physician Burnout: The Way Forward Shanafelt, Tait D; Dyrbye, Lotte N; West, Colin P
JAMA : the journal of the American Medical Association,
03/2017, Letnik:
317, Številka:
9
Journal Article
ABSTRACT
We introduce a polydisperse version of the streaming instability (SI), where the dust component is treated as a continuum of sizes. We show that its behaviour is remarkably different from ...the monodisperse SI. We focus on tightly coupled particles in the terminal velocity approximation and show that unstable modes that grow exponentially on a dynamical time-scale exist. However, for dust to gas ratios much smaller than unity, they are confined to radial wavenumbers that are a factor $\sim 1/{\overline{\rm St}}$ larger than where the monodisperse SI growth rates peak. Here ${\overline{\rm St}}\ll 1$ is a suitable average Stokes number for the dust size distribution. For dust to gas ratios larger than unity, polydisperse modes that grow on a dynamical time-scale are found as well, similar as for the monodisperse SI and at similarly large wavenumbers. At smaller wavenumbers, where the classical monodisperse SI shows secular growth, no growing polydisperse modes are found under the terminal velocity approximation. Outside the region of validity for the terminal velocity approximation, we have found unstable epicyclic modes that grow on ∼104 dynamical time-scales.
Abstract
Renewable CH
4
produced from electrocatalytic CO
2
reduction is viewed as a sustainable and versatile energy carrier, compatible with existing infrastructure. However, conventional alkaline ...and neutral CO
2
-to-CH
4
systems suffer CO
2
loss to carbonates, and recovering the lost CO
2
requires input energy exceeding the heating value of the produced CH
4
. Here we pursue CH
4
-selective electrocatalysis in acidic conditions via a coordination method, stabilizing free Cu ions by bonding Cu with multidentate donor sites. We find that hexadentate donor sites in ethylenediaminetetraacetic acid enable the chelation of Cu ions, regulating Cu cluster size and forming Cu-N/O single sites that achieve high CH
4
selectivity in acidic conditions. We report a CH
4
Faradaic efficiency of 71% (at 100 mA cm
−2
) with <3% loss in total input CO
2
that results in an overall energy intensity (254 GJ/tonne CH
4
), half that of existing electroproduction routes.
The T7 endonuclease 1 (T7E1) mismatch detection assay is a widely used method for evaluating the activity of site-specific nucleases, such as the clustered regularly interspaced short palindromic ...repeats (CRISPR)-Cas9 system. To determine the accuracy and sensitivity of this assay, we compared the editing estimates derived by the T7E1 assay with that of targeted next-generation sequencing (NGS) in pools of edited mammalian cells. Here, we report that estimates of nuclease activity determined by T7E1 most often do not accurately reflect the activity observed in edited cells. Editing efficiencies of CRISPR-Cas9 complexes with similar activity by T7E1 can prove dramatically different by NGS. Additionally, we compared editing efficiencies predicted by the Tracking of Indels by Decomposition (TIDE) assay and the Indel Detection by Amplicon Analysis (IDAA) assay to that observed by targeted NGS for both cellular pools and single-cell derived clones. We show that targeted NGS, TIDE, and IDAA assays predict similar editing efficiencies for pools of cells but that TIDE and IDAA can miscall alleles in edited clones.
•This work discusses new advances in fluorescent biosensors for cellular neuroscience.•New neuromodulator sensors are being developed.•A variety of sensor options are available depending on the ...question being asked.
Dissecting neuronal structure and function in relation to behavior is an immense undertaking. Researchers require imaging tools to study neuronal activity and biochemical signaling in situ in order to study the roles of neuronal and biochemical activity in information processing. A large number of genetically encoded fluorescent biosensors have been reported in the literature over the past few years as there is a push to develop new technology in neuroscience. Here, we review the classes and characteristics of fluorescent biosensors and highlight some considerations that investigators should keep in mind when choosing their tool. In addition, we discuss recent advances in biosensor development.
The aim of this statement is to review the current data and to make suggestions for the diagnosis and management of both ruptured and unruptured brain arteriovenous malformations.
The writing group ...met in person and by teleconference to establish search terms and to discuss narrative text and suggestions. Authors performed their own literature searches of PubMed, Medline, or Embase, specific to their allocated section, through the end of January 2015. Prerelease review of the draft statement was performed by expert peer reviewers and by the members of the Stroke Council Scientific Oversight Committee and Stroke Council Leadership Committee.
The focus of the scientific statement was subdivided into epidemiology; diagnosis; natural history; treatment, including the roles of surgery, stereotactic radiosurgery, and embolization; and management of ruptured and unruptured brain arteriovenous malformations. Areas requiring more evidence were identified.
Brain arteriovenous malformations are a relatively uncommon but important cause of hemorrhagic stroke, especially in young adults. This statement describes the current knowledge of the natural history and treatment of patients with ruptured and unruptured brain arteriovenous malformations, suggestions for management, and implications for future research.
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