Most atmospheric motions of different spatial scales and precipitation are closely related to phase transitions in clouds. The continuously increasing resolution of large‐scale and mesoscale ...atmospheric models makes it feasible to treat the evolution of individual clouds. The explicit treatment of clouds requires the simulation of cloud microphysics. Two main approaches describing cloud microphysical properties and processes have been developed in the past four and a half decades: bulk microphysics parameterization and spectral (bin) microphysics (SBM). The development and utilization of both represent an important step forward in cloud modeling. This study presents a detailed survey of the physical basis and the applications of both bulk microphysics parameterization and SBM. The results obtained from simulations of a wide range of atmospheric phenomena, from tropical cyclones through Arctic clouds using these two approaches are compared. Advantages and disadvantages, as well as lines of future development for these methods are discussed.
Key Points
Review of concepts of microphysical methods
Analysis of errors in representation of microphysical processes
Comparison of results obtained by different methods
Stokes drift van den Bremer, T. S.; Breivik, Ø.
Philosophical transactions - Royal Society. Mathematical, Physical and engineering sciences/Philosophical transactions - Royal Society. Mathematical, physical and engineering sciences,
01/2018, Letnik:
376, Številka:
2111
Journal Article
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During its periodic motion, a particle floating at the free surface of a water wave experiences a net drift velocity in the direction of wave propagation, known as the Stokes drift (Stokes 1847 ...Trans. Camb. Philos. Soc. 8, 441-455). More generally, the Stokes drift velocity is the difference between the average Lagrangian flow velocity of a fluid parcel and the average Eulerian flow velocity of the fluid. This paper reviews progress in fundamental and applied research on the induced mean flow associated with surface gravity waves since the first description of the Stokes drift, now 170 years ago. After briefly reviewing the fundamental physical processes, most of which have been established for decades, the review addresses progress in laboratory and field observations of the Stokes drift. Despite more than a century of experimental studies, laboratory studies of the mean circulation set up by waves in a laboratory flume remain somewhat contentious. In the field, rapid advances are expected due to increasingly small and cheap sensors and transmitters, making widespread use of small surface-following drifters possible. We also discuss remote sensing of the Stokes drift from high-frequency radar. Finally, the paper discusses the three main areas of application of the Stokes drift: in the coastal zone, in Eulerian models of the upper ocean layer and in the modelling of tracer transport, such as oil and plastic pollution. Future climate models will probably involve full coupling of ocean and atmosphere systems, in which the wave model provides consistent forcing on the ocean surface boundary layer. Together with the advent of new space-borne instruments that can measure surface Stokes drift, such models hold the promise of quantifying the impact of wave effects on the global atmosphere-ocean system and hopefully contribute to improved climate projections.
This article is part of the theme issue ‘Nonlinear water waves’.
Cerebral autoregulation is the intrinsic ability of the brain to maintain adequate cerebral perfusion in the presence of blood pressure changes. A large number of methods to assess the quality of ...cerebral autoregulation have been proposed over the last 30 years. However, no single method has been universally accepted as a gold standard. Therefore, the choice of which method to employ to quantify cerebral autoregulation remains a matter of personal choice. Nevertheless, given the concept that cerebral autoregulation represents the dynamic relationship between blood pressure (stimulus or input) and cerebral blood flow (response or output), transfer function analysis became the most popular approach adopted in studies based on spontaneous fluctuations of blood pressure. Despite its sound theoretical background, the literature shows considerable variation in implementation of transfer function analysis in practice, which has limited comparisons between studies and hindered progress towards clinical application. Therefore, the purpose of the present white paper is to improve standardisation of parameters and settings adopted for application of transfer function analysis in studies of dynamic cerebral autoregulation. The development of these recommendations was initiated by (but not confined to) the Cerebral Autoregulation Research Network (CARNet – www.car-net.org).
Around 40-50% of all triple-negative breast cancer (TNBC) patients achieve a pathological complete response (pCR) after treatment with neoadjuvant chemotherapy (NAC). The identification of biomarkers ...predicting the response to NAC could be helpful for personalized treatment. This systematic review provides an overview of putative biomarkers at baseline that are predictive for a pCR following NAC. Embase, Medline and Web of Science were searched for articles published between January 2010 and August 2022. The articles had to meet the following criteria: patients with primary invasive TNBC without distant metastases and patients must have received NAC. In total, 2045 articles were screened by two reviewers resulting in the inclusion of 92 articles. Overall, the most frequently reported biomarkers associated with a pCR were a high expression of Ki-67, an expression of PD-L1 and the abundance of tumor-infiltrating lymphocytes, particularly CD8+ T cells, and corresponding immune gene signatures. In addition, our review reveals proteomic, genomic and transcriptomic markers that relate to cancer cells, the tumor microenvironment and the peripheral blood, which also affect chemo-sensitivity. We conclude that a prediction model based on a combination of tumor and immune markers is likely to better stratify TNBC patients with respect to NAC response.
Estimates of the prevalence of Parkinson's disease in North America have varied widely and many estimates are based on small numbers of cases and from small regional subpopulations. We sought to ...estimate the prevalence of Parkinson's disease in North America by combining data from a multi-study sampling strategy in diverse geographic regions and/or data sources. Five separate cohort studies in California (2), Minnesota (1), Hawaii USA (1), and Ontario, Canada (1) estimated the prevalence of PD from health-care records (3), active ascertainment through facilities, large group, and neurology practices (1), and longitudinal follow-up of a population cohort (1). US Medicare program data provided complementary estimates for the corresponding regions. Using our age- and sex-specific meta-estimates from California, Minnesota, and Ontario and the US population structure from 2010, we estimate the overall prevalence of PD among those aged ≥45 years to be 572 per 100,000 (95% confidence interval 537-614) that there were 680,000 individuals in the US aged ≥45 years with PD in 2010 and that that number will rise to approximately 930,000 in 2020 and 1,238,000 in 2030 based on the US Census Bureau population projections. Regional variations in prevalence were also observed in both the project results and the Medicare-based calculations with which they were compared. The estimates generated by the Hawaiian study were lower across age categories. These estimates can guide health-care planning but should be considered minimum estimates. Some heterogeneity exists that remains to be understood.
In-depth structural analysis of biorefined lignin is imperative to understand its physicochemical properties, essential for its efficient valorization to renewable materials and chemicals. Up to now, ...research on Reductive Catalytic Fractionation (RCF) of lignocellulose biomass, an emerging biorefinery technology, has strongly focused on the formation, separation and quantitative analysis of the abundant lignin-derived phenolic monomers. However, detailed structural information on the linkages in RCF lignin oligomers, constituting up to 50 wt% of RCF lignin, and their quantification, is currently lacking. This study discloses new detailed insights into the pine wood RCF lignin oil's molecular structure through the combination of fractionation and systematic analysis, resulting in the first assignment of the major RCF-derived structural units in the
1
H-
13
C HSQC NMR spectrum of the RCF oligomers. Specifically, β-5 γ-OH, β-5 ethyl, β-1 γ-OH, β-1 ethyl, β-β 2x γ-OH, β-β THF, and 5-5 inter-unit linkages were assigned unambiguously, resulting in the quantification of over 80% of the lignin inter-unit linkages and end-units. Detailed inspection of the native lignin inter-unit linkages and their conversion reveals the occurring hydrogenolysis chemistry and the unambiguous proof of absence of lignin fragment condensation during proper RCF processing. Overall, the study offers an advanced analytical toolbox for future RCF lignin conversion and lignin structural analysis research, and valuable insights for lignin oil valorization purposes.
In-depth structural analysis of pine wood RCF lignin discloses new detailed insights into the RCF lignin oil's molecular structure.
Depression has been associated with increased mortality rates, and modifying mechanisms have not yet been elucidated. We examined whether specific subtypes or characteristics of late-life depression ...predict mortality.
A cohort study including 378 depressed older patients according to DSM-IV criteria and 132 never depressed comparisons. The predictive value of depression subtypes and characteristics on the six-year mortality rate, as well as their interaction with somatic disease burden and antidepressant drug use, were studied by Cox proportional hazard analysis adjusted for demographic and lifestyle characteristics.
Depressed persons had a higher mortality risk than non-depressed comparisons (HR = 2.95 95% CI: 1.41-6.16, p = .004), which lost significance after adjustment for age, sex, education, smoking, alcohol, physical activity, number of prescribed medications and somatic comorbidity. Regarding depression subtypes and characteristics, only minor depression was associated with a higher mortality risk when adjusted for confounders (HR = 6.59 95% CI: 1.79-24.2, p = .005).
Increased mortality rates of depressed older persons seem best explained by unhealthy lifestyle characteristics and multiple drug prescriptions. The high mortality rate in minor depression, independent of these factors, might point to another, yet unknown, pathway towards mortality for this depression subtype. An explanation might be that minor depression in later life reflects depressive symptoms due to underlying aging-related processes, such as inflammation-based sickness behavior, frailty, and mild cognitive impairment, which have all been associated with increased mortality.
Abstract
Seaweeds are seen as important future feedstock for Europe, providing biomass for food, feed, and other applications. Seaweeds can contribute to a circular food system a protein transition ...and bio-based economy. Europe is a minor player in the world market dominated by the Asian producers and processors. According to the FAO, total production of aquatic plants (dominated by seaweed) was 30 million tonnes in 2016, with China (47.9%) and Indonesia (38, 7%) dominating production. This article discusses the challenges to seaweed production and use in Europe and formulates future directions for upscaling the European seaweed sector. From a People, Planet, Profit perspective, there is no need to focus on producing large volumes of seaweed per se. We need to focus on nature-inclusive production systems, producing the right amount of the right seaweeds, based on the carrying capacity of the European seas. The seaweed sector must avoid developing along the “old” economy’s way of cost leadership but develop along the way of the “new” circular economy. Seaweeds should not be seen as a new product “added” to the market but become an integral part of the European food system, being used for human consumption, feed and improving production processes.
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