Air motion determination by tracking humidity patterns in isentropic layers

Determining air motions by tracking humidity patterns in isentropic layers was investigated. Upper-air rawinsonde data from the NSSL network and from the AVE-II pilot experiment were used to simulate temperature and humidity profile data that will eventually be available from geosynchronous satellites. Polynomial surfaces that move with time were fitted to the mixing-ratio values of the different isentropic layers. The velocity components of the polynomial surfaces are part of the coefficients that are determined in order to give an optimum fitting of the data. In the mid-troposphere, the derived humidity motions were in good agreement with the winds measured by rawinsondes so long as there were few or no clouds and the lapse rate was relatively stable. In the lower troposphere, the humidity motions were unreliable primarily because of nonadiabatic processes and unstable lapse rates. In the upper troposphere, the humidity amounts were too low to be measured with sufficient accuracy to give reliable results. However, it appears that humidity motions could be used to provide mid-tropospheric wind data over large regions of the globe

Three-dimensional reconstruction of CME-driven shock-streamer interaction from radio and EUV observations: a different take on the diagnostics of coronal magnetic fields

On 2014 October 30, a band-splitted type II radio burst associated with a coronal mass ejection (CME) observed by the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamic Observatory (SDO) occurred over the southeast limb of the Sun. The fast expansion in all directions of the plasma front acted as a piston and drove a spherical fast shock ahead of it, whose outward progression was traced by simultaneous images obtained with the Nan\c{c}ay Radioheliograph (NRH). The geometry of the CME/shock event was recovered through 3D modeling, given the absence of concomitant stereoscopic observations, and assuming that the band-splitted type II burst was emitted at the intersection of the shock surface with two adjacent low-Alfven speed coronal streamers. From the derived spatiotemporal evolution of the standoff distance between shock and CME leading edge, we were finally able to infer the magnetic field strength $B$ in the inner corona. A simple radial profile of the form $B(r) = (12.6 \pm 2.5) r^{-4}$ nicely fits our results, together with previous estimates, in the range $r = 1.1-2.0$ solar radii.Comment: Accepted for publication in Astronomy & Astrophysics Letter

Advanced Techniques for Design and Manufacturing in Marine Engineering

Modern engineering design processes are driven by the extensive use of numerical simulations, and naval architecture as well as ocean engineering are no exception. Structural design or fluid dynamic performance evaluation can only be carried out by means of several dedicated pieces of software. Classical naval design methodology can take advantage of the integration of these pieces of software, giving rise to more robust design in terms of shape, structural and hydrodynamic performances, and manufacturing processes. This Special Issue (SI) on “Advanced Techniques for Design and Manufacturing in Marine Engineering”, published in the Journal of Marine Science and Engineering, aimed to invite researchers and engineers from both academia and industry to publish the latest progress in design and manufacturing techniques in marine engineering as well as to debate current issues and future perspectives in this research area. After a rigorous peer review process we accepted 11 papers [1–11], covering a wide range of topics related to the themes proposed in the Special Issue. In [1], machine-learningbased algorithms are developed in order to enhance the real-time decision process of an AUV sailing yacht. In [2], topology optimization techniques and laser powder bed fusion manufacturing have been synergically adopted to redesign the bulb of sailing yachts, leading to drag reduction and improving overall boat performance. In [3], the topic of sail design is discussed by means of numerical fluid structure interaction methods and a practical tool is proposed to support the analyst during the design process of a yacht sail plan. The sail design process is also investigated in [4] but using different tools, such as combining a velocity prediction program, RANS computations, and analytical approaches. The problem of grid generation in a CFD model has been studied in [5], where the authors propose, for the particular shape of a submarine, an automated procedure based on Cartesian adaptive grids. The applicability of a CFD numerical technique to a complex biphase fluid medium is the key point of [6], where the robustness of the method is tested to simulate the ventilation phenomenon occurring in stepped hull planing motor yachts. In [7], an analytical tool incorporating the main dimensional naval coefficients of a sailing boat is adopted during the early design stage, with the additional aim of quickly predicting the overall resistance of the hull. In [8], different pieces of sensor information have been used by the authors to train an algorithm able to control water sample collection in deep water. Computational methods have been used in [9] to determine the resistance of ship fuel tanks when subjected to an increased internal pressure. In [10], a simulation model has been used to design a platform able to compensate for the wave action on a vessel, with particular attention to the shape optimization of the structure in order to reduce the total weight. Finally, in [11], CFD tools using moving meshes have been adopted to simulate turbulent flows that originate in an oscillating water column device and move a Savonius turbine

UV AND RADIO OBSERVATIONS OF THE CORONAL SHOCK ASSOCIATED WITH THE 2002 JULY 23 CORONAL MASS EJECTION EVENT

We report on the analysis of a fast coronal mass ejection (CME)-driven shock observed on 2002 July 23 with the Ultraviolet Coronagraph Spectrometer (UVCS) on board the Solar and Heliospheric Observatory (SOHO). The CME was first detected in white light by the Large Angle and Spectrometric Coronagraph Experiment (LASCO), and shock-associated type II metric emission was recorded by several ground-based radio spectrographs. The evolution of the excess broadening of the O VI λ1032 line profiles observed by UVCS at 1.63 R☉ is consistent with the passage of a CME-driven shock surface enveloping a bubble-type, conically expanding CME, and its dynamics is found to be well associated with the complex, multiple type II radio emission detected in the metric band. Our results suggest that there might be a deficiency of ion heating in the present event with respect to what was observed in previous CME shocks detected by UVCS, and that this paucity might be attributed to different local plasma conditions, such as higher ambient coronal plasma β. We conclude that plasma β could be an important parameter in determining the effect of ion heating at collisionless shock fronts in the solar corona

Representing and analysing molecular and cellular function in the computer

Determining the biological function of a myriad of genes, and understanding how they interact to yield a living cell, is the major challenge of the post genome-sequencing era. The complexity of biological systems is such that this cannot be envisaged without the help of powerful computer systems capable of representing and analysing the intricate networks of physical and functional interactions between the different cellular components. In this review we try to provide the reader with an appreciation of where we stand in this regard. We discuss some of the inherent problems in describing the different facets of biological function, give an overview of how information on function is currently represented in the major biological databases, and describe different systems for organising and categorising the functions of gene products. In a second part, we present a new general data model, currently under development, which describes information on molecular function and cellular processes in a rigorous manner. The model is capable of representing a large variety of biochemical processes, including metabolic pathways, regulation of gene expression and signal transduction. It also incorporates taxonomies for categorising molecular entities, interactions and processes, and it offers means of viewing the information at different levels of resolution, and dealing with incomplete knowledge. The data model has been implemented in the database on protein function and cellular processes 'aMAZE' (http://www.ebi.ac.uk/research/pfbp/), which presently covers metabolic pathways and their regulation. Several tools for querying, displaying, and performing analyses on such pathways are briefly described in order to illustrate the practical applications enabled by the model

Red Blood Cells from Individuals with Abdominal Obesity or Metabolic Abnormalities Exhibit Less Deformability upon Entering a Constriction.

Abdominal obesity and metabolic syndrome (MS) are multifactorial conditions associated with increased risk of cardiovascular disease and type II diabetes mellitus. Previous work has demonstrated that the hemorheological profile is altered in patients with abdominal obesity and MS, as evidenced for example by increased whole blood viscosity. To date, however, no studies have examined red blood cell (RBC) deformability of blood from individuals with obesity or metabolic abnormalities under typical physiological flow conditions. In this study, we pumped RBCs through a constriction in a microfluidic device and used high speed video to visualize and track the mechanical behavior of ~8,000 RBCs obtained from either healthy individuals (n = 5) or obese participants with metabolic abnormalities (OMA) (n = 4). We demonstrate that the OMA+ cells stretched on average about 25% less than the healthy controls. Furthermore, we examined the effects of ingesting a high-fat meal on RBC mechanical dynamics, and found that the postprandial period has only a weak effect on the stretching dynamics exhibited by OMA+ cells. The results suggest that chronic rigidification of RBCs plays a key role in the increased blood pressure and increased whole blood viscosity observed in OMA individuals and was independent of an acute response triggered by consumption of a high-fat meal