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Current advancements in waterborne autonomous systems, together with the development of cloud-based service-oriented architectures and the recent availability of low-cost underwater acoustic modems and long-range above water wireless devices, enabled the development of new applications to support ships and port activities. Unmanned Surface Vehicle (USV) can, for instance, be used to perform bathymetry and environmental data collection tasks to ensure under-keel clearance and to monitor the quality of the water. Similarly, Remotely Operated Vehicles (ROVs) can be deployed to inspect ship hulls and typical port infrastructure elements, such as quay and sheet pilling walls. In this paper we present the complete system deployed for the small-scale demonstrations of the Robotic Vessels as-a-Service (RoboVaaS) project, which introduces an on-demand service-based cloud system that dispatches Unmanned Vehicles (UVs) capable of performing the required service either autonomously or piloted. These vessels are able to interact with sensors deployed in the port and with the shore station through an integrated underwater and above water network. The developed system has been validated through sea trials and showcased through an underwater sensor data collection service. The results of the test presented in this paper provide a proof-of-concept of the system design and indicate its technical feasibility. It also shows the need for further developments for a mature technology allowing on-demand robotic maritime assistance services in real operational scenarios., Comment: 54 pages

Early diagnosis of MSA-C in patients with late-onset cerebellar ataxia (LOCA) may prove difficult. We therefore describe and evaluate the performance of the new "phalanx sign" (PS), that should be looked for during the nose-finger test to distinguish MSA-C from idiopathic late-onset ataxia (ILOCA).Sensitivity, specificity, positive predictive value, negative predictive value and interrater reliability of PS were assessed in three groups: 21 MSA-C, 23 ILOCA and 20 age-matched healthy subjects.PS was positive for 61.9% of MSA-C patients', 4.3% of ILOCA patients' and in none of healthy subjects' evaluations. PS discriminated MSA-C from ILOCA (p 0.001) with a sensitivity of 61.9%, a specificity of 95.7%, a positive predictive value of 92.9%, a negative predictive value of 73.3% and a substantial interrater reliability (Kappa = 0.7273).PS could be a helpful, easy and reproducible sign for the early diagnosis of MSA-C in patients with LOCA.

Multiple sclerosis is an autoimmune disease that affects the central nervous system. Dysfunction of the immune system leads to lesions that cause motor, sensory, cognitive, visual and/or sphincter disturbances. In the long term, these disorders can progress towards an irreversible handicap. The diagnosis takes time because there are no specific criteria to diagnose multiple sclerosis. To realize the diagnosis, a combination of clinical, biological, and radiological arguments is therefore required. Hence, there is a need to identify multiple sclerosis biomarkers. Some biomarkers target immunity through the detection of oligoclonal bands, the measurement of the IgG index and cytokines. During the physiopathological process, the blood-brain barrier can be broken, and this event can be identified by measuring metalloproteinase activity and diffusion of gadolinium in the brain by magnetic resonance imaging. Markers of demyelination and of astrocyte and microglial activity may also be of interest as well as markers of neuronal damage and mitochondrial status. The measurement of different lipids in the plasma and cerebrospinal fluid can also provide suitable information. These different lipids include fatty acids, fatty acid peroxidation products, phospholipids as well as oxidized derivatives of cholesterol (oxysterols). Oxysterols could constitute new biomarkers providing information on the form of multiple sclerosis, the outcome of the disease and the answer to treatment.

The denudation of soil or soft rock surfaces by non-concentrated flow is mostly estimated by relating the sediment discharge observed at the outlet of a plot or natural micro-catchment to their respective surface areas. This approach generates an average denudation rate, but ignores spatial patterns of erosion and deposition. A well established approach to capture such spatial differences are pins, which deliver a highly precise point measurement of surface elevation change. Advances in the development of Unmanned Aerial Vehicles (UAVs) and imagine processing in the past decades offer an additional tool for mapping erosion and deposition at millimetre scale for continuous surfaces. In this study, pin and UAV-derived erosion data for a badland area in the Karoo rangelands, South Africa, are compared. The results show that typical annual erosion rates in the study area are lower than the differences between two DEMs generated a year apart. This illustrates that in situations where erosion rates are low, pins still offer the faster and more reliable results. For their extrapolation, on the other hand, UAV-derived DEMs provide suitable topographic data.

Decreasing motivation in science classes is often reported in many countries. Georgia, one of the post Soviet countries, has overcome the highly centralised educational system and nowadays implements a new national educational reform. National reforms demand more student-active and inquiry-based learning. Many Georgian teachers aren’t ready for these changes and need professional development training to enhance their professional skills in Inquiry-Based Science Education (IBSE). Therefore Ilia State University offers special continuous professional development (CPD) programs for science teachers in the frame of PROFILES project. The aim of the research was to determine what profession oriented attitudes and concerns Georgian in-service science teachers have regarding IBSE and what changes are visible after the implementation of PROFILES-based CPD programme. In order to conduct the research, the Stages of Concern model was used. 40 teachers took part in the two terms of the CPD programme. Research shows that the implemented CPD programme fosters the professional attitudes and concerns of Georgian science teachers in a positive manner. Therefore, it can be highly recommended to use the framework of the PROFILES-based CPD programme(s). Key words: IBSE, in-service teachers in Georgia, professional development, stages of concern.

Exosomes are small vesicles secreted by different immune cells and which display anti-tumoral properties. Stimulation of RBL-2H3 cells with ionomycin triggered phospholipase D2 (PLD2) translocation from plasma membrane to intracellular compartments and the release of exosomes. Although exosomes carry the two isoforms of PLD, PLD2 was enriched and specifically sorted on exosomes when overexpressed in cells. PLD activity present on exosomes was clearly increased following PLD2 overexpression. PLD2 activity in cells was correlated to the amount of exosome released, as measured by FACS. Therefore, the present work indicates that exosomes can vehicle signaling enzymes.

Exosomes are small vesicles (60-100 nm) secreted by various cell types upon the fusion of endosomal compartments with the plasma membrane. Exosomes from antigen-presenting cells (APC), such as B lymphocytes and dendritic cells (DC), bear MHC class II molecules. In addition, the injection of DC-derived exosomes was reported to elicit potent T cell responses in vivo. Here, we analyzed the activation of specific T cells by MHC class II-bearing exosomes in vitro. The rat mast cell line, RBL-2H3, was engineered to express human class II molecules uniformly loaded with an antigenic peptide [HLA-DR1-hemagglutinin (HA)]. These cells secreted exosomes bearing DR1 class II molecules upon stimulation by a calcium ionophore or IgE receptor cross-linking. Exosomes bearing DR1-HA(306-318) complexes activated HA/DR1-specific T cells only weakly, whereas the cross-linking of such exosomes to latex beads increased stimulation of specific T cells. By contrast, the incubation of free exosomes with DC resulted in the highly efficient stimulation of specific T cells. Thus, exosomes bearing MHC class II complexes must be taken up by professional APC for efficient T cell activation.

Bone marrow-derived mast cells as well as dendritic cells, macrophages and B lymphocytes express major histocompatibility complex (MHC) class II molecules. In mast cells, the majority of MHC class II molecules reside in intracellular cell type-specific compartments, secretory granules. To understand the molecular basis for the localisation of MHC class II molecules in secretory granules, MHC class II molecules were expressed, together with the invariant chain, in the mast cell line, RBL-2H3. Using electron and confocal microscopy, we observed that in RBL-2H3 cells, mature and immature class II molecules accumulate in secretory granules. Two particular features of class II transport accounted for this intracellular localization: first, a large fraction of newly synthesized MHC class II molecules remained associated with invariant chain fragments. This defect, resulting in a slower rate of MHC class II maturation, was ascribed to a low cathepsin S activity. Second, although a small fraction of class II dimers matured (i.e. became free of invariant chain), allowing their association with antigenic peptides, they were retained in secretory granules. As a consequence of this intracellular localization, cell surface expression of class II molecules was strongly increased by cell activation stimuli which induced the release of the contents of secretory granules. Our results suggest that antigen presentation, and thereby antigen specific T cell stimulation, are regulated in mast cells by stimuli which induce mast cell activation.

The Haynesville shale gas play in North Louisiana poses a number of significant technical challenges. One of the most daunting is penetrating the hard, abrasive Hosston sandstone-shale sequence and hard Knowles limestone in the intermediate section of the overburden. The high strength and interbedded nature of these formations trigger bit and drillstring vibration that can lead to short, slow bit runs and unacceptably high cost per foot. The operator applied a systematic Drilling Efficiency Optimization (DEO) approach encompassing well planning, well execution and post-well analysis to drive performance improvement through these formations. Optimization efforts focused on polycrystalline diamond compact (PDC) bit design, bit hydraulics, positive displacement motor (PDM) selection, soft torque rotary system (STRS) utilization, bottom hole assembly (BHA) design and active management of drilling parameters. Combined, these efforts reduced cost per foot and days per thousand feet by over 50% while drilling approximately 70 wells over a two year period.

Significant drilling performance improvement was achieved over a two year period in the HPHT Haynesville Shale Play in North Louisiana. Technical challenges include drilling through abrasive, high compressive strength formations, bottom hole temperatures exceeding 360°F, sour gas and shut-in surface pressures near 10,000 psi. The wells are horizontal with 12,500 to 14,500 ft TVD, and 16,500 to 18,500 ft MD. The application and optimization of managed pressure drilling (MPD), underbalanced drilling (UBD), hard rock drilling, casing drilling, casing design and installation procedures will be discussed.

Given the current economic climate and continued volatility in oil and natural gas prices, extracting maximum benefit from drilling performance optimization is key to the economical exploitation of many resource plays around the world. Shell Upstream Americas is employing a highly effective performance improvement team to help drive performance optimization and the delivery of top quartile performance on its wells in North America and beyond. Central to this group is a dedicated team of optimization engineers that deliver drilling efficiency optimization techniques, the innovative use of real-time optimization centers, and value-adding root-cause failure investigations to various land and offshore well delivery teams in a fit-for-purpose way. Using the optimization approaches taken, it has been possible to help accelerate well delivery times and associated learning curves by as much as a factor of three, often in a minimum amount of time. A main conclusion is therefore that this approach is a highly effective way to bring performance optimization focus to field operations. This paper highlights the modus operandi of these optimization engineers, the techniques and tools they employ, and the remarkable results achieved. The workflow and organizational structure was applied to well delivery optimization with projects ranging from shale gas drilling in the Continental US and Canada as well as hard rock drilling in the Middle East.

The primary purpose of this study was to determine if portable spirometers can be successfully used in an emergency department (ED) in children with an acute exacerbation of asthma. The secondary purpose of this study was to determine if a validated clinical asthma score (CAS) correlates with the spirometry results in children with an acute exacerbation of asthma.Children between the ages of 6 and 17 years who presented to an urban free-standing children's hospital ED with an acute exacerbation of asthma were enrolled in our study. On arrival, the CAS was recorded and then portable spirometry was performed. Attempts were continued until acceptable and reproducible flow loop measurements were obtained or until the patient was unable to perform further attempts. Outcomes included success at spirometry and correlation of spirometry with the CAS.A total of 101 patients were enrolled in this study. Of those patients, only 35 (35%) were able to successfully perform portable spirometry. Successful spirometry attempts were associated with older age (10.4 vs. 8.9, p = .01), lower respiratory rates (24.8 vs. 30.2, p = .001), lower heart rates (110 vs. 124, p = .004), and lower CASs (8.4 vs. 9.7, p = .001). Increasing asthma severity correlated with a decreased likelihood of successfully obtaining a useful forced expiratory volume in 1 second (FEV(1)) measurement (p = .013). Compared with cases of mild asthma, a patient with moderate asthma is 33% less likely to be able to perform spirometry, and a patient with severe asthma 93% less likely to perform spirometry. The CAS correlated poorly with the more objective measure of FEV(1)% predicted in those with mild asthma.Many children are incapable of using portable spirometry for the evaluation of acute exacerbations of asthma in the ED. The clinical asthma scoring system demonstrated poor correlation with portable spirometry measurements in terms of severity classification.

Summary Purpose To estimate the association between signal characteristic of dynamic enhanced MRI using curve types and angiogenesis in solitary pulmonary nodules. Materials and methods Thirty-six patients with a solitary pulmonary nodule (SPN) ranging in size from 6 to 37mm (median 17mm) underwent dynamic contrast enhanced MRI with a time interval of 10s over a total period of 4min. Resulting from the time–intensity curves four different enhancement curve profiles (A–D) were defined: type A with strong increase followed by early washout, type B with strong increase without washout, type C with slow increase and type D without relevant increase. Maximum peak ( P max ), slope of the first bolus transit (slope) and washout were calculated. Microvessel densities (MVD) were counted at the margins and at the center of the nodules. The mean MVD of each nodule was calculated. Enhancement characteristics were correlated with MVD grouped by diagnosis and by curve types. Curve types were correlated with the score of vascular endothelial growth factor (VEGF). Results The frequency of malignancy was 55% (20/36). Using curve types for differentiation between malignant and benign SPN, the sensitivity, specificity and accuracy were 100%, 75% and 89%, respectively. The correlation between P max and MVD mean for all nodules was moderate ( r s =0.4, P =0.02). A relevant correlation was found between P max and MVD margin in curve type A ( r s =0.63; P =0.04) and P max and MVD mean in curve type C ( r s =0.86; P =0.006). No positive correlation was found between P max and MVD (mean, center and margin) in curve type B. No significant correlation was found for slope and washout. VEGF score correlated positively with curve types ( r s =0.67; P Conclusion A relevant association between perfusion curve profiles and angiogenesis was found in malignant nodules having early washout and in benign lesion with a slow increase of enhancement. In cases of strong signal increase without washout additional factors for enhancement must be considered. The use of curve profiles could allow for the estimation of the extent of VEGF.

Fluorescent lipid probes were used to track lipid trafficking between parent RBL cells and exosomes. We have checked the intracellular labeling of exosomes ("in vivo labeling") from parent cell incubated with either Bodipy-Cer, Bodipy-PC, or NBD-PC. Bodipy-PC labeled equally cells and exosomes, whereas Bodipy-Cer, a Golgi marker, was enriched in exosomes. Golgi membranes participated effectively in exosome biogenesis since cell incubation with brefeldin A leads to a modified phospholipid/protein ratio in exosomes. At the opposite, NBD-PC, a plasma membrane marker weakly labeled exosome membranes. Sorting of subpopulations indicated that the MHC-II containing exosomes were enriched in Bodipy-PC, whereas tetraspanin(CD 63 or CD81)-containing exosomes are essentially labeled with Bodipy-Cer and Bodipy-PC. These results indicated that RBL released two main subpopulations of exosomes that can be discriminated by their protein and lipid contents. When the bulk of exosomes was labeled after their purification ("in vitro labeling") with either of the above-mentioned lipid probes, the Bodipy-Cer was the only one to incorporate noticeably in all the subpopulations, indicating that the previous results obtained during "in vivo labeling" monitored real intracellular lipid trafficking between organelles and exosomes. Bodipy-Cer was further used as a tool to measure the respective amounts of each subpopulations. CD63, MHC II, and CD81-containing exosomes accounted for 47%, 32%, and 21%, respectively, of total exosomes.

Antigen recognition by clonotypic B cell receptor (BcR) is the first step of B lymphocytes differentiation into plasmocytes. This B cell function is dependent on efficient major histocompatibility complex (MHC) class II–restricted presentation of BcR-bound antigens. In this work, we analyzed the subcellular mechanisms underlying antigen presentation after BcR engagement on B cells. In quiescent B cells, we found that MHC class II molecules mostly accumulated at the cell surface and in an intracellular pool of tubulovesicular structures, whereas H2-M molecules were mostly detected in distinct lysosomal compartments devoid of MHC class II. BcR stimulation induced the transient intracellular accumulation of MHC class II molecules in newly formed multivesicular bodies (MVBs), to which H2-M was recruited. The reversible downregulation of cathepsin S activity led to the transient accumulation of invariant chain–MHC class II complexes in MVBs. A few hours after BcR engagement, cathepsin S activity increased, the p10 invariant chain disappeared, and MHC class II–peptide complexes arrived at the plasma membrane. Thus, BcR engagement induced the transient formation of antigen-processing compartments, enabling antigen-specific B cells to become effective antigen-presenting cells.