ABSTRACT We present a new, publicly available set of Los Alamos OPLIB opacity tables for the elements hydrogen through zinc. Our tables are computed using the Los Alamos ATOMIC opacity and plasma ...modeling code, and make use of atomic structure calculations that use fine-structure detail for all the elements considered. Our equation of state model, known as ChemEOS, is based on the minimization of free energy in a chemical picture and appears to be a reasonable and robust approach to determining atomic state populations over a wide range of temperatures and densities. In this paper we discuss in detail the calculations that we have performed for the 30 elements considered, and present some comparisons of our monochromatic opacities with measurements and other opacity codes. We also use our new opacity tables in solar modeling calculations and compare and contrast such modeling with previous work.
Coronavirus disease 2019 (COVID-19) is a viral infection which can cause a variety of respiratory, gastrointestinal, and vascular symptoms. The acute illness phase generally lasts no more than 2–3 ...weeks. However, there is increasing evidence that a proportion of COVID-19 patients experience a prolonged convalescence and continue to have symptoms lasting several months after the initial infection. A variety of chronic symptoms have been reported including fatigue, dyspnea, myalgia, exercise intolerance, sleep disturbances, difficulty concentrating, anxiety, fever, headache, malaise, and vertigo. These symptoms are similar to those seen in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), a chronic multi-system illness characterized by profound fatigue, sleep disturbances, neurocognitive changes, orthostatic intolerance, and post-exertional malaise. ME/CFS symptoms are exacerbated by exercise or stress and occur in the absence of any significant clinical or laboratory findings. The pathology of ME/CFS is not known: it is thought to be multifactorial, resulting from the dysregulation of multiple systems in response to a particular trigger. Although not exclusively considered a post-infectious entity, ME/CFS has been associated with several infectious agents including Epstein–Barr Virus, Q fever, influenza, and other coronaviruses. There are important similarities between post-acute COVID-19 symptoms and ME/CFS. However, there is currently insufficient evidence to establish COVID-19 as an infectious trigger for ME/CFS. Further research is required to determine the natural history of this condition, as well as to define risk factors, prevalence, and possible interventional strategies.
Summary
Background
Non‐cardiac chest pain is one of the most common functional gastrointestinal disorders. By recognising that gastro‐oesophageal reflux disease (GERD), oesophageal dysmotility and ...oesophageal hypersensitivity are the main underlying mechanisms of NCCP, a more directed therapeutic approach has been developed.
Aim
To determine the value of the current therapeutic modalities for NCCP.
Methods
Electronic (Pubmed/Medline/Cochrane central) and manual search.
Results
Double‐dose PPI treatment for two months is a reasonable first choice approach in patients with NCCP because GERD is the most common aetiology. Studies evaluating the role of medical therapy in NCCP patients with hypercontractile oesophageal motility suggest a limited value to muscle relaxants like calcium channel blockers (nifedipine, diltiazem), nitrates and sildenafil. While most trials evaluating pain modulators are small and many are not placebo‐controlled, these type of medications appear efficacious in both patients with NCCP due to oesophageal dysmotility and those with functional chest pain. Cognitive behavioural therapy has been extensively studied in patients with functional chest pain with good results. Other psychological techniques such as hypnotherapy, group therapy or coping skills have been scarcely studied but appear to be effective in NCCP patients.
Conclusion
Medical, endoscopic and surgical therapeutic options are available for the treating physician, although some patients with non‐cardiac chest pain may require a multimodal therapeutic approach.
The microgrid is an emerging trend in modern power systems. Microgrids consist of controllable power sources, storage, and loads. An elaborate control infrastructure is established to regulate and ...synchronize the interaction of these components. The control scheme is divided into a hierarchy of several layers, where each layer is composed of multi-agents performing their dedicated functions and arriving at a consensus of corrective values. Lateral and horizontal interaction of such multi-agents forms a comprehensive hierarchical control structure that regulates the microgrid operation to achieve a compendium of objectives, including power sharing, voltage, and frequency regulation. The success of a multi-agent-based control scheme is dependent on the health of the communication media that is used to relay measurements and control signals. Delays in the transmission of control signals result in an overall deterioration of the control performance and non-convergence. This paper proposes novel multi-agent moving average estimators to mitigate the effect of latent communication links and establishes a hierarchical control scheme incorporating these average estimators to accurately arrive at system values during communication delays. Mathematical models are established for the complete microgrid system to test the stability of the proposed method against conventional consensus-based methods. Case-wise simulation studies and lab-scale experimental verification further establish the efficacy and superiority of the proposed control scheme in comparison with other conventionally used control methods.
Chronic obstructive pulmonary disease (COPD) is characterized by chronic airway inflammation and episodes of worsening respiratory symptoms and pulmonary function, termed acute exacerbations of COPD ...(AECOPD). AECOPD episodes are associated with heightened airway inflammation and are often triggered by infection. A subset of COPD patients develops frequent exacerbations despite maximal existing standard medical therapy. It is therefore clear that a targeted and more effective prevention strategy is needed. Immunoglobulins are glycoprotein molecules that are secreted by B lymphocytes and plasma cells and play a critical role in the adaptive immune response against many pathogens. Altered serum immunoglobulin levels have been observed in patients with immunodeficiencies and inflammatory diseases. Serum immunoglobulin has also been identified as potential biomarkers of AECOPD frequency. Since plasma-derived polyvalent immunoglobulin treatment is effective in preventing recurrent infections in immunodeficient patients and in suppressing inflammation in many inflammatory diseases, it may be conceivable that immunoglobulin treatment may be effective in preventing recurrent AECOPD. In this article, we provide a review of the current knowledge on immunoglobulin treatment in patients with COPD and discuss plausible mechanisms as to how immunoglobulin treatment may work to reduce AECOPD frequency.
Boltzmann electron kinetic simulations are performed to study the time development of the electron energy distribution function (EEDF) in plasma resulting from neon gas subject to a 40 fs x-ray free ...electron laser radiation source. The simulations are performed without any assumptions of electron temperature. The distributions are calculated as a function of time through 40 fs using Boltzmann kinetics, including the appropriate processes that alter state populations and electron energy. The calculations are also extended into the picosecond regime, after the laser pulse, to track the thermalization of free electrons. Results are presented that predict the evolution of the charge-state distribution, effective temperature, the photon spectrum, as well as the EEDF.
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