Climatic and oceanic associations with daily rainfall extremes over southern Africa

Changes in climate variability and, in particular, changes in extreme climate events are likely to be of far more significance for environmentally vulnerable regions than changes in the mean state. It is generally accepted that sea-surface temperatures (SSTs) play an important role in modulating rainfall variability. Consequently, SSTs can be prescribed in global and regional climate modelling in order to study the physical mechanisms behind rainfall and its extremes. Using a satellite-based daily rainfall historical data set, this paper describes the main patterns of rainfall variability over southern Africa, identifies the dates when extreme rainfall occurs within these patterns, and shows the effect of resolution in trying to identify the location and intensity of SST anomalies associated with these extremes in the Atlantic and southwest Indian Ocean. Derived from a Principal Component Analysis (PCA), the results also suggest that, for the spatial pattern accounting for the highest amount of variability, extremes extracted at a higher spatial resolution do give a clearer indication regarding the location and intensity of anomalous SST regions. As the amount of variability explained by each spatial pattern defined by the PCA decreases, it would appear that extremes extracted at a lower resolution give a clearer indication of anomalous SST regions

Following Natures Lead: On the Construction of Membrane-Inserted Toxins in Lipid Bilayer Nanodiscs

Bacterial toxin or viral entry into the cell often requires cell surface binding and endocytosis. The endosomal acidification induces a limited unfolding/refolding and membrane insertion reaction of the soluble toxins or viral proteins into their translocation competent or membrane inserted states. At the molecular level, the specific orientation and immobilization of the pre-transitioned toxin on the cell surface is often an important prerequisite prior to cell entry. We propose that structures of some toxin membrane insertion complexes may be observed through procedures where one rationally immobilizes the soluble toxin so that potential unfolding ↔ refolding transitions that occur prior to membrane insertion orientate away from the immobilization surface in the presence of lipid micelle pre-nanodisc structures. As a specific example, the immobilized prepore form of the anthrax toxin pore translocon or protective antigen can be transitioned, inserted into a model lipid membrane (nanodiscs), and released from the immobilized support in its membrane solubilized form. This particular strategy, although unconventional, is a useful procedure for generating pure membrane-inserted toxins in nanodiscs for electron microscopy structural analysis. In addition, generating a similar immobilized platform on label-free biosensor surfaces allows one to observe the kinetics of these acid-induced membrane insertion transitions. These platforms can facilitate the rational design of inhibitors that specifically target the toxin membrane insertion transitions that occur during endosomal acidification. This approach may lead to a new class of direct anti-toxin inhibitors

A dynamical framework for the origin of the diagonal South Pacific and South Atlantic convergence zones

The South Pacific Convergence Zone (SPCZ) and South Atlantic Convergence Zone (SACZ) are diagonal bands of precipitation that extend from the equator southeastward into the Southern Hemisphere over the western Pacific and Atlantic Oceans, respectively. With mean precipitation rates over 5 mm day−1, they are a major component of the tropical and global climate in austral summer. However, their basic formation mechanism is not fully understood. Here, a conceptual framework for the diagonal convergence zones is developed, based on calculations of the vorticity budget from reanalysis and Rossby wave theory. Wave trains propagate eastward along the Southern Hemisphere subtropical jet, with initially quasi-circular vorticity centres. In the zonally sheared environment on the equatorward flank of the jet, these vorticity centres become elongated and develop a northwest-southeast tilt. Ray tracing diagnostics in a non-divergent, barotropic Rossby wave framework then explain the observed equatorward propagation of these diagonal vorticity structures toward the westerly ducts over the equatorial Pacific and Atlantic. The baroclinic component of these circulations leads to destabilisation and ascent ahead of the cyclonic vorticity anomaly in the wave, triggering deep convection because of the high sea surface temperatures in this region. Latent heat release then forces additional ascent and strong upper-tropospheric divergence, with an associated anticyclonic vorticity tendency. A vorticity budget shows that this cancels out the advective cyclonic vorticity tendency in the wave train over the SPCZ, and dissipates the wave within a day. The mean SPCZ is consequently comprised of the sum of these pulses of diagonal bands of precipitation. Similar mechanisms also operate in the SACZ. However, the vorticity anomalies in the wave trains are stronger, and the precipitation and negative feedback from the divergence and anticyclonic vorticity tendency are weaker, resulting in continued propagation of the wave and a more diffuse diagonal convergence zone

GENDER SPECIFICATION OF POLISH NOUNS NAMING PEOPLE: THE LANGUAGE SYSTEM AND PUBLIC DEBATE ARGUMENTS

Changes in language practices take place against a backdrop of social pressures for greater gender equality. The topic of the current paper concerns the grammatical and social complexities of a language reform for gender fair representation in the Polish context. This “socially-motivated” language reform, which aims to enhance social equality, is underpinned but also challenged by the language system on the one hand and the public debate on the other. Therefore, the grammatical constraints afforded by the language system need to be investigated in the context of the social attitudes to gender relations in Poland, as well as attitudes to the proposed linguistic innovations. It is our aim here to reflect upon the current social debate about the process of ongoing language change, more specifically to consider the relevant linguistic and social arguments. These arguments are revealed in a close analysis of a range of texts of varying genre, social reach and significance, written as a reaction to the usage dilemmas often faced by speakers. The texts were collected between January 2014 and November 2019. The paper concludes with suggestions of the best policy to deal with a highly controversial socio-linguistic issue such as this one

The 2010-2011 drought in the Horn of Africa in ECMWF reanalysis and seasonal forecast products

This study evaluates the use of European Centre for Medium-Range Weather Forecasts (ECMWF) products in monitoring and forecasting drought conditions during the recent 2010–2011 drought in the Horn of Africa (HoA). The region was affected by a precipitation deficit in both the October–December 2010 and March–May 2011 rainy seasons. These anomalies were captured by the ERA-Interim reanalysis (ERAI), despite its limitations in representing the March–May interannual variability. Soil moisture anomalies of ERAI also identified the onset of the drought condition early in October 2010 with a persistent drought still present in September 2011. This signal was also evident in normalized difference vegetation index (NDVI) remote sensing data. The precipitation deficit in October–December 2010 was associated with a strong La Niña event. The ECMWF seasonal forecasts for the October–December 2010 season predicted the La Niña event from June 2010 onwards. The forecasts also predicted a below-average October–December rainfall, from July 2010 onwards. The subsequent March–May rainfall anomaly was only captured by the new ECWMF seasonal forecast system in the forecasts starting in March 2011. Our analysis shows that a recent (since 1999) drying in the region during the March–May season is captured by the new ECMWF seasonal forecast system and is consistent with recently published results. The HoA region and its population are highly vulnerable to future droughts, thus global monitoring and forecasting of drought, such as that presented here, will become increasingly important in the future. Copyright © 2012 Royal Meteorological Societ

Diurnal Characteristics of Rainfall over the Contiguous United States and Northern Mexico in the Dynamically Downscaled Reanalysis Dataset (US10)

The diurnal characteristics of summer rainfall in the contiguous United States and northern Mexico were examined with the United States reanalysis for 5 years in 10-km horizontal resolution (US10), which is dynamically downscaled from the National Centers for Environmental Prediction National Center for Atmospheric Research (NCEP-NCAR) Global Reanalysis 1 using the Regional Spectral Model (RSM). The hourly precipitation outputs demonstrate a realistic structure in the temporal evolution of the observed rainfall episodes and their magnitudes across the United States without any prescriptions of the observed rainfall to the global reanalysis and the downscaled regional reanalysis. Nighttime rainfall over the Great Plains associated with eastward-propagating, mesoscale convective systems originating from the Rocky Mountains is also represented realistically in US 10, while the original reanalysis and most general circulation models (GCMs) have difficulties in capturing the series of nocturnal precipitation events in summer over the Plains. The results suggest an important role of the horizontal resolution of the model in resolving small-scale, propagating convective systems to improve the diurnal cycle of summer rainfall.open3

Shear Moduli Determination Using Torsional Stiffness Measurements

The orthotropic shear moduli were determined for three different reconstituted wood materials. Shear moduli determination was accomplished using the respective formulae that define torsional stiffness for a linear elastic orthotropic rectangular parallelepiped. Applied test procedures required the experimental evaluation of torsional stiffness constants for rectangular specimens of decreasing width to thickness slenderness ratio. Anticlastic plate bending tests were also conducted to derive in-plane shear modulus values using standard ASTM D3044 procedures. In-plane shear modulus values derived from applied torsional theory were found to be in reasonable agreement with the standard ASTM test procedure

Iosipescu Shear Test Apparatus Applied to Wood Composites

In-plane and transverse (through-the-thickness) shear strength properties were evaluated for three wood composite materials. A modified Iosipescu test apparatus was used to determine shear strength relative to the six possible material orientations. In-plane shear was also characterized using ASTM D1037-87 test standards. The Iosipescu shear test method was developed originally for metals testing. However, different forms of the test device have evolved for purposes of shear evaluation with numerous nonisotropic materials being evaluated. Previous research for various materials has shown satisfactory results with repeatability and apparent shear failure. The current research specifically utilized the University of Wyoming version of the original shear test device. Iosipescu test results for in-plane shear strength were comparable to values derived from the ASTM test method. Transverse shear strength values were found to exceed the magnitude of previously published ASTM test results. Greater directional or material orientation differences were observed for transverse shear properties

Zastosowanie analgetyków opioidowych w leczeniu objawowym pacjentów z rozpoznaniem zaawansowanych nienowotworowych chorób płuc

Abstract Studies on the endogenous opioid system have demonstrated its presence, including opioid receptors, not only in the central nervous system but also in the respiratory tract. The presence of these receptors, both centrally and peripherally, provides the potential for treatment of respiratory symptoms, such as dyspnea and cough, with systemic and local application of opioids. These are especially important when symptomatic treatment becomes a priority in patient care.Badania nad endogennym układem opioidowym wykazały obecność receptorów opioidowych, nie tylko w ośrodkowym układzie nerwowym, ale także w drogach oddechowych. Chociaż mechanizmy duszności nie są w pełni zrozumiałe, obecność tych receptorów, zarówno centralnie jak i obwodowo, zapewnia możliwość leczenia objawów ze strony dróg oddechowych, takich jak duszność i kaszel, przy ogólnoustrojowym lub miejscowym zastosowaniu opioidów, kiedy leczenie przyczynowe zaawansowanych nienowotworowych choroby płuc jest niewystarczające. Podczas gdy jakość badań dotyczących stosowania opioidów w leczeniu kaszlu pozostaje niska, istnieje coraz więcej dowodów potwierdzających skuteczność i bezpieczeństwo parenteralnych i nebulizowanych opioidów w leczeniu duszności.