Steric sea level changes from ocean reanalyses at global and regional scales

Sea level has risen significantly in the recent decades and is expected to rise further based on recent climate projections. Ocean reanalyses that synthetize information from observing networks, dynamical ocean general circulation models, and atmospheric forcing data offer an attractive way to evaluate sea level trend and variability and partition the causes of such sea level changes at both global and regional scales. Here, we review recent utilization of reanalyses for steric sea level trend investigations. State-of-the-science ocean reanalysis products are then used to further infer steric sea level changes. In particular, we used an ensemble of centennial reanalyses at moderate spatial resolution (between 0.5 × 0.5 and 1 × 1 degree) and an ensemble of eddy-permitting reanalyses to quantify the trends and their uncertainty over the last century and the last two decades, respectively. All the datasets showed good performance in reproducing sea level changes. Centennial reanalyses reveal a 1900–2010 trend of steric sea level equal to 0.47 ± 0.04 mm year−1, in agreement with previous studies, with unprecedented rise since the mid-1990s. During the altimetry era, the latest vintage of reanalyses is shown to outperform the previous ones in terms of skill scores against the independent satellite data. They consistently reproduce global and regional upper ocean steric expansion and the association with climate variability, such as ENSO. However, the mass contribution to the global mean sea level rise is varying with products and its representability needs to be improved, as well as the contribution of deep and abyssal waters to the steric sea level rise. Similarly, high-resolution regional reanalyses for the European seas provide valuable information on sea level trends, their patterns, and their causes

Neuro-hormonal effects of physical activity in the elderly.

Thanks to diagnostic and therapeutic advances, the elderly population is continuously increasing in the western countries. Accordingly, the prevalence of most chronic age-related diseases will increase considerably in the next decades, thus it will be necessary to implement effective preventive measures to face this epidemiological challenge. Among those, physical activity exerts a crucial role, since it has been proven to reduce the risk of cardiovascular diseases, diabetes, obesity, cognitive impairment and cancer. The favorable effects of exercise on cardiovascular homeostasis can be at least in part ascribed to the modulation of the neuro-hormonal systems implicated in cardiovascular pathophysiology. In the elderly, exercise has been shown to affect catecholamine secretion and biosynthesis, to positively modulate the renin-angiotensin-aldosterone system and to reduce the levels of plasma brain natriuretic peptides. Moreover, drugs modulating the neuro-hormonal systems may favorably affect physical capacity in the elderly. Thus, efforts should be made to actually make physical activity become part of the therapeutic tools in the elderly. © 2013 Femminella, de Lucia, Iacotucci, Formisano, Petraglia, Allocca, Ratto, DAmico, Rengo, Pagano, Bonaduce, Rengo and Ferrara

Oxidation and Cross-Linking in the Curing of Air-Drying Artists' Oil Paints

In this study, the chemistry of air-drying artist's oil paint curing and aging up to 24 months was studied. The objective is to improve our molecular understating of the processes that lead to the conversion of the fluid binder into a dry film and how this evolves with time, which is at the base of a better comprehension of degradation phenomena of oil paintings and relevant to the artists' paint manufacturing industry. To this aim, a methodological approach based on thermogravimetric (TG) analysis, differential scanning calorimetry (DSC), gas chromatography-mass spectrometry (GC-MS), and analytical pyrolysis coupled with gas chromatography and mass spectrometry (Py-GC-MS) was implemented. Model paintings based on linseed oil and safflower oil (a drying and a semidrying oil, respectively) mixed with two historically relevant pigments - lead white (a through drier) and synthetic ultramarine blue (a pigment often encountered in degraded painting layers) - were investigated. The oil curing under accelerated conditions (80 °C under air flow) was followed by isothermal TG analysis. The oxygen uptake profiles were fit by a semiempiric equation that allowed to study the kinetics of the oil oxidation and estimate oxidative degradation. The DSC signal due to hydroperoxide decomposition and radical recombination was used to monitor the radical activity over time and to evaluate the stability of peroxides formed in the paint layers. GC-MS was performed at 7 and 24 months of natural aging to investigate the noncovalently cross-linked fractions and Py-GC-MS to characterize the whole organic fraction of the model paintings, including the cross-linked network. We show that the oil-pigment combination may have a strong influence on the relative degree of oxidation of the films formed with respect to its degree of cross-linking, which may be correlated with the literature on the stability of painting layers. Undocumented pathways of oxidation are also highlighted

The DSC monitoring of oil melting to follow the oil curing

The drying of an oil paint is due to the polyunsaturations of the oil in the binder. Polyunsaturated oils dry trough an autoxidation process in which the double bonds of linolenic and linoleic acids naturally react with the oxygen present in the atmosphere. The gradual conversion of the liquid oil through a soft gel to a rubbery solid occurs as a result of a multistep free radical chain reaction. During the propagation step, hydroperoxides are formed. A method frequently used to follow the oil curing is the DSC monitoring of the peroxide decomposition peak during time. Since the oil polymerization affects its crystallinity, we propose here an altemative method to asses the oil curing. The melting peak of linseed oil samples is measured at different times of curing and compared with the pro\ufb01le of the peroxide decomposition peak over time. The comparison shows that the two phenomena are strongly correlated and that, when the maximum of the peroxide content is reached, the melting peak disappears. The study of the DSC melting peak is therefore proposed as a valid alternative tool to monitor the curing of an oil paint

Effects of losartan treatment on cardiac autonomic control during volume loading in patients with DCM

This study evaluated the effect of angiotensin II receptor blockade on cardiac autonomic control adaptation and urine output in response to acute isotonic volume load in patients with idiopathic dilated cardiomyopathy (DCM) and asymptomatic to mildly symptomatic heart failure. Left ventricular volumes and heart rate variability measurements were assessed at baseline and during intravenous saline load in 14 patients before and after 2 mo of losartan treatment. After losartan treatment, blood pressure values were lower, whereas left ventricular ejection fraction was higher (F = 79, P50 ms) decreased during saline load in untreated patients (F = 3.1, P< 0.05 and F = 6.5, P< 0.01, respectively), but not after losartan. Similarly, a decrease in very low frequency (F = 3.2, P< 0.05), low-frequency (F = 2.9, P< 0.05), and high-frequency power (F = 6.1, P< 0.01) after saline load was observed only in untreated patients. In patients with DCM, losartan treatment improves the cardiac autonomic adaptation and increases urine output in response to volume overload

A simple and reliable methodology to detect egg white in art samples

A protocol for a simple and reliable dot-blot immunoassay was developed and optimized to test work of art samples for the presence of specific proteinaceus material (i.e. ovalbumin-based). The analytical protocol has been extensively set up with respect, among the other, to protein extraction conditions, to densitometric analysis and to the colorimetric reaction conditions. Feasibility evaluation demonstrated that a commercial scanner and a free image analysis software can be used for the data acquisition and elaboration, thus facilitating the application of the proposed protocol to commonly equipped laboratories and to laboratories of museums and conservation centres. The introduction of method of standard additions in the analysis of fresh and artificially aged laboratory-prepared samples, containing egg white and various pigments, allowed us to evaluate the matrix effect and the effect of sample aging and to generate threshold density values useful for the detection of ovalbumin in samples from ancient works of art. The efficacy of the developed dot-blot immunoassay was proved testing microsamples from 13th–16th century mural paintings of Saint Francesco Church in Lodi (Italy). Despite the aging, the altered conditions of conservation, the complex matrix, and the micro-size of samples, the presence of ovalbumin was detected in all those mural painting samples where mass-spectrometry-based proteomic analysis unambiguously detected ovalbumin peptides

Elaia, Pergamon's maritime satellite:The rise and fall of an ancient harbour city shaped by shoreline migration

Throughout human history, communication and trade have been key to society. Because maritime trade facilitated the rapid transportation of passengers and freight at relatively low cost, harbours became hubs for traffic, trade and exchange. This general statement holds true for the Pergamenian kingdom, which ruled wide parts of today's western Turkey during Hellenistic times. Its harbour, located at the city of Elaia on the eastern Aegean shore, was used extensively for commercial and military purposes. This study reconstructs the coastal evolution in and around the ancient harbour of Elaia and compares the observed environmental modifications with archaeological and historical findings. We use micropalaeontological, sedimentological and geochemical proxies to reconstruct the palaeoenvironmental dynamics and evolution of the ancient harbour. The geoarchaeological results confirm the archaeological and historical evidence for Elaia's primacy during Hellenistic and early Roman times, and the city's gradual decline during the late Roman period. Furthermore, our study demonstrates that Elaia holds a unique position as a harbour city during ancient times in the eastern Aegean region, because it was not greatly influenced by the high sediment supply associated with river deltas. Consequently, no dredging of the harbour basins is documented, creating exceptional geo-bioarchives for palaeoenvironmental reconstructions

Complex systems and the technology of variability analysis

Characteristic patterns of variation over time, namely rhythms, represent a defining feature of complex systems, one that is synonymous with life. Despite the intrinsic dynamic, interdependent and nonlinear relationships of their parts, complex biological systems exhibit robust systemic stability. Applied to critical care, it is the systemic properties of the host response to a physiological insult that manifest as health or illness and determine outcome in our patients. Variability analysis provides a novel technology with which to evaluate the overall properties of a complex system. This review highlights the means by which we scientifically measure variation, including analyses of overall variation (time domain analysis, frequency distribution, spectral power), frequency contribution (spectral analysis), scale invariant (fractal) behaviour (detrended fluctuation and power law analysis) and regularity (approximate and multiscale entropy). Each technique is presented with a definition, interpretation, clinical application, advantages, limitations and summary of its calculation. The ubiquitous association between altered variability and illness is highlighted, followed by an analysis of how variability analysis may significantly improve prognostication of severity of illness and guide therapeutic intervention in critically ill patients