236 research outputs found
A Comparison of Methods for a Priori Bias Correction in Soil Moisture Data Assimilation
Data assimilation is being increasingly used to merge remotely sensed land surface variables such as soil moisture, snow and skin temperature with estimates from land models. Its success, however, depends on unbiased model predictions and unbiased observations. Here, a suite of continental-scale, synthetic soil moisture assimilation experiments is used to compare two approaches that address typical biases in soil moisture prior to data assimilation: (i) parameter estimation to calibrate the land model to the climatology of the soil moisture observations, and (ii) scaling of the observations to the model s soil moisture climatology. To enable this research, an optimization infrastructure was added to the NASA Land Information System (LIS) that includes gradient-based optimization methods and global, heuristic search algorithms. The land model calibration eliminates the bias but does not necessarily result in more realistic model parameters. Nevertheless, the experiments confirm that model calibration yields assimilation estimates of surface and root zone soil moisture that are as skillful as those obtained through scaling of the observations to the model s climatology. Analysis of innovation diagnostics underlines the importance of addressing bias in soil moisture assimilation and confirms that both approaches adequately address the issue
Влияние ионизирующего излучения высокоэнергетических ионов гелия на процессы формирования протон-проводящих свойств полимерных фторсодержащих фукциональных мембран
What Are Effective Program Characteristics of Self-Management Interventions in Patients With Heart Failure? An Individual Patient Data Meta-analysis
To identify those characteristics of self-management interventions in patients with heart failure (HF) that are effective in influencing health-related quality of life, mortality, and hospitalizations
2nd ESMO Consensus Conference in Lung Cancer: locally advanced stage III non-small-cell lung cancer
To complement the existing treatment guidelines, ESMO organises consensus conferences to focus on specific issues. The 2nd ESMO Consensus Conference on Lung Cancer included 35 experts who met to address several questions on non-small-cell lung cancer (NSCLC). Recommendations were made with reference to grade of recommendation and level of evidence. This paper focuses on locally advanced diseas
Oncogenic ERBB3 Mutations in Human Cancers
SummaryThe human epidermal growth factor receptor (HER) family of tyrosine kinases is deregulated in multiple cancers either through amplification, overexpression, or mutation. ERBB3/HER3, the only member with an impaired kinase domain, although amplified or overexpressed in some cancers, has not been reported to carry oncogenic mutations. Here, we report the identification of ERBB3 somatic mutations in ∼11% of colon and gastric cancers. We found that the ERBB3 mutants transformed colonic and breast epithelial cells in a ligand-independent manner. However, the mutant ERBB3 oncogenic activity was dependent on kinase-active ERBB2. Furthermore, we found that anti-ERBB antibodies and small molecule inhibitors effectively blocked mutant ERBB3-mediated oncogenic signaling and disease progression in vivo
Traces of past activity in the Galactic Centre
The Milky Way centre hosts a supermassive Black Hole (BH) with a mass of
~4*10^6 M_Sun. Sgr A*, its electromagnetic counterpart, currently appears as an
extremely weak source with a luminosity L~10^-9 L_Edd. The lowest known
Eddington ratio BH. However, it was not always so; traces of "glorious" active
periods can be found in the surrounding medium. We review here our current view
of the X-ray emission from the Galactic Center (GC) and its environment, and
the expected signatures (e.g. X-ray reflection) of a past flare. We discuss the
history of Sgr A*'s past activity and its impact on the surrounding medium. The
structure of the Central Molecular Zone (CMZ) has not changed significantly
since the last active phase of Sgr A*. This relic torus provides us with the
opportunity to image the structure of an AGN torus in exquisite detail.Comment: Invited refereed review. Chapter of the book: "Cosmic ray induced
phenomenology in star forming environments" (eds. Olaf Reimer and Diego F.
Torres
Autism as a disorder of neural information processing: directions for research and targets for therapy
The broad variation in phenotypes and severities within autism spectrum disorders suggests the involvement of multiple predisposing factors, interacting in complex ways with normal developmental courses and gradients. Identification of these factors, and the common developmental path into which theyfeed, is hampered bythe large degrees of convergence from causal factors to altered brain development, and divergence from abnormal brain development into altered cognition and behaviour. Genetic, neurochemical, neuroimaging and behavioural findings on autism, as well as studies of normal development and of genetic syndromes that share symptoms with autism, offer hypotheses as to the nature of causal factors and their possible effects on the structure and dynamics of neural systems. Such alterations in neural properties may in turn perturb activity-dependent development, giving rise to a complex behavioural syndrome many steps removed from the root causes. Animal models based on genetic, neurochemical, neurophysiological, and behavioural manipulations offer the possibility of exploring these developmental processes in detail, as do human studies addressing endophenotypes beyond the diagnosis itself
Direct oral anticoagulants versus vitamin K antagonists after recent ischemic stroke in patients with atrial fibrillation
Objective:
We compared outcomes after treatment with direct oral anticoagulants (DOAC) and Vitamin‐K antagonists (VKA) in patients with atrial fibrillation (AF) and a recent cerebral ischemia.
Methods:
We conducted an individual patient data analysis of 7 prospective cohort studies. We included patients with AF and a recent cerebral ischemia (<3 months before starting oral anticoagulation) and a minimum follow‐up of 3 months. We analyzed the association between type of anticoagulation (DOAC vs. VKA) with the composite primary endpoint (recurrent ischemic stroke [AIS], intracerebral hemorrhage [ICH], or mortality) using mixed effects Cox proportional hazards regression models; we calculated adjusted hazard ratios (HR) with 95% confidence intervals (95% CI).
Results:
We included 4912 patients (median age 78 years [IQR 71‐84]; 2331 [47.5%] women, median NIHSS at onset 5 [IQR 2‐12]); 2256 (45.9%) patients received VKA and 2656 (54.1%) DOAC. The median time from index event to starting oral anticoagulation was 5 days (IQR 2‐14) for VKA and 5 days (IQR 2‐11) for DOAC (p=0.53). There were 262 AIS (4.4%/year), 71 ICH (1.2%/year) and 439 deaths (7.4%/year) during the total follow‐up of 5970 patient‐years. Compared to VKA, DOAC treatment was associated with reduced risks of the composite endpoint (HR 0.82, 95%CI 0.67‐1.00, p=0.05) and ICH (HR 0.42, 95%CI 0.24‐0.71, p<0.01); we found no differences for the risk of recurrent AIS (HR 0.91, 95%CI 0.70‐1.19, p=0.5) and mortality (HR 0.83, 95%CI 0.68‐1.03, p=0.09).
Interpretation:
DOAC treatment commenced early after recent cerebral ischemia related to AF was associated with reduced risk of poor clinical outcomes compared to VKA, mainly due to lower risks of ICH
Operative Treatment of Intra-Articular Distal Radius Fractures With versus Without Arthroscopy: study protocol for a randomised controlled trial
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