Sigh in supine and prone position during acute respiratory distress syndrome

Interventions aimed at recruiting the lung of patients with acute respiratory distress syndrome (ARDS) are not uniformly effective. Because the prone position increases homogeneity of inflation of the lung, we reasoned that it might enhance its potential for recruitment. We ventilated 10 patients with early ARDS (PaO2/FIO2, 121 +/- 46 mm Hg; positive end-expiratory pressure, 14 +/- 3 cm H2O) in supine and prone, with and without the addition of three consecutive "sighs" per minute to recruit the lung. Inspired oxygen fraction, positive end-expiratory pressure, and minute ventilation were kept constant. Sighs increased PaO2 in both supine and prone (p < 0.01). The highest values of PaO2 (192 +/- 41 mm Hg) and end-expiratory lung volume (1840 +/- 790 ml) occurred with the addition of sighs in prone and remained significantly elevated 1 hour after discontinuation of the sighs. The increase in PaO2 associated with the sighs, both in supine and prone, correlated linearly with the respective increase of end-expiratory lung volume (r = 0.82, p < 0.001). We conclude that adding a recruitment maneuver such as cyclical sighs during ventilation in the prone position may provide optimal lung recruitment in the early stage of ARDS

Effect of air exposure time on erodibility of intertidal mud flats

This study investigates the influence of air exposure time on the erodibility of intertidal mud flats, emphasizing the role of evaporation in altering sediment strength and cohesion. Through a comprehensive approach combining laboratory experiments, fieldwork, and numerical modelling, it explores the dynamic interactions between sediment properties and environmental conditions. The research reveals that drying significantly reduces sediment erodibility, with pronounced effects observed during the initial hours of air exposure. Laboratory tests demonstrate a direct correlation between drying time and increased yield stress for both artificial and field-derived mud samples. Field observations further support these results, showing spatial and temporal variations in water content and shear strength across various locations on a tidal flat. The study emphasizes the critical impact of mud content on water retention and the subsequent effect on sediment stability. The incorporation of drying time into erosion formulations within a numerical model highlights the importance of considering evaporation processes in predicting the morphological evolution of tidal flats. This research contributes to a better understanding of sediment transport dynamics in intertidal zones, offering insights into the mechanisms driving the growth and stability of mud flats. It underscores the necessity of integrating evaporation effects into cohesive sediment transport models to enhance the accuracy of predictions concerning the erosion and accretion of intertidal environments

Vertical Specialization, Tariff Shirking and Trade

The core idea behind the paper is that trade policy matters for the organization of global value chains, a notion largely neglected by economists but which has important implications for our understanding of trade and the international transmission of trade policy shocks. We develop a theoretical model in which a firm's ability to spatially separate manufacturing from headquarter services gives them the flexibility to circumvent economy-specific tariff changes by switching their assembly location abroad. We show that tariff shirking increases the elasticity of bilateral trade to economy-specific tariff hikes due to an extra extensive margin effect. Furthermore, we show that tariff shirking affects the vulnerability of headquarter services and manufacturing to trade policy shocks in opposite ways. While tariff shirking dampens the vulnerability of headquarter services to trade policy shocks, it amplifies the vulnerability of manufacturing to trade policy shocks. Using firm-level and province-level export data from the People's Republic of China, we provide evidence in line with the theoretical model

L\u2019ospedale psichiatrico di Verona tra passato, presente e futuro

Il contributo illustra le potenzialit\ue0 del patrimonio archivistico prodotto dall'ospedale psichiatrico San Giacomo di Tomba di Verona (1880-1980) e l'importanza del luogo San Giacomo, del quale restano a tutt'oggi significative testimonianze architettoniche, che meritano di essere valorizzate in quanto parte integrante della citt\ue0 e della sua memoria storica

A Selective Metal-Mediated Approach for the Efficient Self-Assembling of Multi-Component Photoactive Systems

We report on the efficient use of different coordinative affin- ities to quantitatively construct a three-component multi- chromophore system containing one free-base porphyrin, one aluminium(III) monopyridylporphyrin, and one ruth- enium(II) tetraphenylporphyrin in a single step. The Al III monopyridylporphyrin plays the pivotal role in directing the correct self-assembly process, and it behaves as the antenna unit for the photoinduced processes of interest. A two-com- ponent system, containing the same free-base porphyrin and one aluminium(III) tetraphenylporphyrin, was prepared for comparative studies. Both systems are remarkably stable in chlorinated solutions. Their photophysical behaviour was studied in detail by stationary and time-resolved emission techniques. In the two-component system, fast and efficient singlet energy transfer from the Al\u2013porphyrin to the free- base porphyrin is observed; in the three-component system, upon excitation of the Al\u2013porphyrin, a fast (minor of 250 ps) electron transfer process from the Ru\u2013porphyrin to the aluminium\u2013porphyrin is observed