Remote Points Research Articles

Post-translational environmental switch of RadA activity by extein-intein interactions in protein splicing.

Post-translational control based on an environmentally sensitive intervening intein sequence is described. Inteins are invasive genetic elements that self-splice at the protein level from the flanking host protein, the exteins. Here we show in Escherichia coli and in vitro that splicing of the RadA intein located in the ATPase domain of the hyperthermophilic archaeon Pyrococcus horikoshii is strongly regulated by the native exteins, which lock the intein in an inactive state. High temperature or solution conditions can unlock the intein for full activity, as can remote extein point mutations. Notably, this splicing trap occurs through interactions between distant residues in the native exteins and the intein, in three-dimensional space. The exteins might thereby serve as an environmental sensor, releasing the intein for full activity only at optimal growth conditions for the native organism, while sparing ATP consumption under conditions of cold-shock. This partnership between the intein and its exteins, which implies coevolution of the parasitic intein and its host protein may provide a novel means of post-translational control.

Estimation of point source fugitive emission rates from a single sensor time series: A conditionally-sampled Gaussian plume reconstruction

Emerging mobile fugitive emissions detection and measurement approaches require robust inverse source algorithms to be effective. Two Gaussian plume inverse approaches are described for estimating emission rates from ground-level point sources observed from remote vantage points. The techniques were tested using data from 41 controlled methane release experiments (14 studies) and further investigated using 7 field studies executed downwind of oil and gas well pads in Wyoming. Analyzed measurements were acquired from stationary observation locations 18–106 m downwind of the emission sources. From the fluctuating wind direction, the lateral plume geometry is reconstructed using a derived relationship between the wind direction and crosswind plume position. The crosswind plume spread is determined with both modeled and reconstructed Gaussian plume approaches and estimates of source emission rates are found through inversion. The source emission rates were compared to a simple point source Gaussian emission estimation approach that is part of Draft EPA Method OTM 33A. Compared to the known release rates, the modeled, reconstructed, and point source Gaussian controlled release results yield average percent errors of −5%, -2%, and 6% with standard deviations of 29%, 25%, and 37%, respectively. Compared to each other, the three methods agree within 30% for 78% of all 48 observations (41 CR and 7 Wyoming).

The slack-based measure model based on supporting hyperplanes of production possibility set

The original slack-based measure (SBM) model evaluates the efficiency of decision making units (DMUs) referring to the furthest frontier point within a range. Hence the projection may go to a remote point on the efficient frontier which may be inappropriate as a reference point. In this paper we propose a new variant for the improvement of efficiency scores in SBM models. It is based on the determination of strong hyperplanes of the production possibility set (PPS). The approach presented here improves the currently used Tone method both, from the time consumption and computational points of view. Comparative examples, as well as a case study, are given to illustrate the new procedure.

Placement of PMUs Considering Measurement Phase-Angle Mismatch

Phasor measurement units (PMUs) are becoming an important component in the power grid. The PMUs provide time-synchronized measurements of multiple remote measurement points, enabling more accurate and real-time monitoring of the system state. Heuristically, it is difficult to tell how the placement of a PMU at a specific location in the power system would affect the state estimation error, not to say the effect of the PMU synchronization and measurement accuracy. In this paper, we derive the posterior Cramér-Rao bound (PCRB) on the state estimation error based on a measurement model which considers the phase-angle mismatch from PMU measurements. We then propose a PMU placement strategy using the derived PCRB. The greedy algorithm is used to solve the optimization problem. The results are then compared with other heuristics, with the optimal solution through an exhaustive search (for small systems), and with a lower bound on the optimal placement obtained through convex relaxation. For some design criteria, the objective functions are submodular, which guarantees a performance bound on the greedy solution. For other design criteria where the objective functions are not submodular, numerical examples demonstrate the effectiveness of the greedy algorithms.

Experimental studies of the local reflection of long waves from an underwater slope

The regularities of the local reflection of long waves from underwater slopes with different inclinations were investigated using the data of a laboratory experiment that was performed at a scale of 1 : 20 compared to the full-scale conditions. It is shown that the coefficient of the local reflection of waves decreases with the distance from the coast. The dissipation of the wave energy significantly reduces the local reflection coefficient near the shoreline and at the most remote sea point of the underwater slope. This leads to the existence of maximum of the local reflection coefficient at the boundary of the wave breaking. The presence of peculiarities of the bottom topography, such as an underwater bar or trench, can also significantly change the local reflection coefficient and influence its values in the offshore part of the underwater slope.

Localic remote points revisited

We consider remote points in general extensions of frames, with an emphasis on perfect extensions. For a strict extension ?XL ? L determined by a set X of filters in L, we show that if there is an ultrafilter in X then the extension has a remote point. In particular, if a completely regular frame L has a maximal completely regular filter which is an ultrafilter, then ?L ? L has a remote point, where ?L is the Stone-C?ch compactification of L. We prove that in certain extensions associated with radical ideals and l-ideals of reduced f-rings, remote points induced by algebraic data are exactly non-essential prime ideals or non-essential irreducible l-ideals. Concerning coproducts, we show that if M1 ? L1 and M2 ? L2 are extensions of T1-frames, then each of these extensions has a remote point if the extensionM1?M2?L1?L2 has a remote point.

Business Continuity Management (BCM) Applied to Transpetro's National Operational Control Center - CNCO

Abstract TRANSPETRO (Petrobras Transporte S.A.) undertakes oil, products, ethanol, biofuels, and natural gas pipeline transportation and storage activities. It is in charge of more than 14,000 kilometers of pipelines - among oil and gas pipelines - which interconnect all Brazilian regions and supply the country's most remote points. Currently, TRANSPETRO, through its National Operational Control Center (CNCO), undertakes the operations and monitoring of more than 91% of liquid transportation pipelines and distribution lines and 100% of natural gas pipelines for the Brazilian state company, PETROBRAS, and private companies. The centralization of TRANSPETRO's pipelines and terminals operations, started by 2002 with the creation of its Control Center, which uses SCADA technology, changed substantially the way the company operates its pipelines. This decision required a very large cultural change and breaking of paradigms. In addition to requirements for better operational reliability, which involves SCADA Technology and its supporting infrastructure (Electric, Air-conditioning, Fire Detection and Extinguishing, etc), it were also introduced reliability requirements in processes management of the operation and human reliability. In this context, the CNCO is part of the triad of Reliability, covering the segments of the operational, technological and human process. Considering this context, the present work will describe the Program for Business Continuity Management (BCM), which is now being implemented in TRANSPETRO. Methodology and guidelines established for Managing Business Continuity and Incident Response (Crisis Management), focusing on CNCO, using as a ‘benchmark’ the BSI 2231-3 [1] . As a result of the BCM program on the CNCO, will be presented some evidence such as: the benefits arising from the implementation of the Business Impact Analysis (BIA); Qualitative Risk Assessment, based at the FRAAP methodology and a sample of the system used to evaluate the level of maturity (stages) of the implementation of the program, considering as benchmark BSI-2231-3 (BSI PAS 56) Examples of the various documents that make up the BCM will be showed. It will also be presented, a summary of the SCADA architecture, and, as an example, the process of assessing the level of maturity of the model Maintenance Management and Administration applied to SCADA Technology, based on heuristic model, developed by professionals responsible for SCADA, as one of the solutions that can be used, among others, to ensure business continuity.

Fuzzy Neural-Network-Based Controller

Using a controller is necessary for any automation system. The controller must be cheap, reliable, user friendly and not cause any problems for inputs and outputs. Classical control systems like proportional integral derivative (PID) put adequate results of linear systems and continuous-time. In fact, real control systems are time-variant, with non-linearity and poorly calculated dynamic variables. For this reason, conventional control systems need an expert person to adjust controller parameters in general. Sometimes an operator is required to solve control problems. Human control is not completely reliable. Also, it does not include any electronic communication. In modern factories, every point must be monitored and electronically controlled from remote points when necessary. In this study, including every electronic communication channel, a simplified handling, low-cost, reliable, Fuzzy Neural Network Controller (FNNC) is designed.

Muscle pain syndrome: Evaluation and treatment

Muscle pain syndrome: Evaluation and treatment

An Investigation of Earth Grid Performance Using Graphene-Coated Copper

Large power systems are normally operated with their neutral points directly earthed. At a major generating or switching station, this results in the provision of a large earth grid buried in the ground. The design of earthing systems requires a worst case approach. There is a possibility of heavy currents flowing into the earth grid from the overhead earth wires through the tower during a line conductor fault and from lightning strikes. The flow of earth current during a fault or lightning conditions results in a rise of earth grid potential with respect to a physically remote earth point, which can lead to unsafe conditions under some conditions for personnel and connected electrical plant. This paper aims to investigate the potential of adding novel coatings to the conventional copper earth grid conductors to enhance overall conductivity and diminish corrosion. This contributes to lowering the rise of earth grid potential. Graphene-coated copper performance as an earth grid conductor is evaluated with staged low voltage fault and the corrosion behavior in both a destructive and nondestructive environment. A comparison of the simulation software packages CDEGS and CST is also carried out using lightning strike conditions.

A Distributed Antenna System for Indoor Accurate WiFi Localization

Specific infrastructures are a key challenge for indoor geo-localization systems. In particular, an accurate narrowband localization technique using 802.11 g WiFi signals is proposed in this letter. The related system architecture is built on the basis of radio over fiber topology of distributed antennas systems that are increasingly deployed in buildings. In particular, the system proposed collects the microwave signals using remote and local access points linked by ${\hbox {62.5-}}\mu\hbox{m}$ core diameter multimode fibers and enables to determine the location transmitter with an accuracy of less than 6.4 cm.

Simulation-Based Planning and Control of Transport Flows in Port Logistic Systems

In highly dynamic and uncertain transport conditions, transport transit time has to be continuously monitored so that the service level is ensured at a proper cost. The aim of this research is to propose and to test a procedure which allows an agile planning and control of transport flows in port logistic systems. The procedure couples an agent-based simulation and a queueing theory model. In this paper, the transport scheduling performed by an agent at the intermodal terminal was taken into consideration. The decision-making agent takes into account data which is acquired in remote points of the system. The obtained results indicate the relevance of continuously considering, for the transport planning and control, the expected transit time and further waiting times along port logistic systems.

Durable fear memories require PSD-95.

Traumatic fear memories are highly durable but also dynamic, undergoing repeated reactivation and rehearsal over time. While overly persistent fear memories underlie anxiety disorders such as posttraumatic stress disorder, the key neural and molecular mechanisms underlying fear memory durability remain unclear. Post-synaptic density 95 (PSD-95) is a synaptic protein regulating glutamate receptor anchoring, synaptic stability and certain types of memory. Employing a loss-of-function mutant mouse lacking the guanylate kinase domain of PSD-95 (PSD-95GK), we analyzed the contribution of PSD-95 to fear memory formation and retrieval, and sought to identify the neural basis of PSD-95-mediated memory maintenance using ex vivo immediate-early gene mapping, in vivo neuronal recordings and viral-mediated knockdown approaches. We show that PSD-95 is dispensable for the formation and expression of recent fear memories, but essential for the formation of precise and flexible fear memories and for the maintenance of memories at remote time points. The failure of PSD-95GK mice to retrieve remote cued fear memories was associated with hypoactivation of the infralimbic cortex (IL) (not anterior cingulate (ACC) or prelimbic cortex), reduced IL single-unit firing and bursting, and attenuated IL gamma and theta oscillations. Adeno-associated PSD-95 virus-mediated knockdown in the IL, not ACC, was sufficient to impair recent fear extinction and remote fear memory, and remodel IL dendritic spines. Collectively, these data identify PSD-95 in the IL as a critical mechanism supporting the durability of fear memories over time. These preclinical findings have implications for developing novel approaches to treating trauma-based anxiety disorders that target the weakening of overly persistent fear memories.

A Novel Fuzzy Clustering Algorithm Based on K-Means Algorithm

Conventional K-means algorithm cannot obtain elevated clustering specific rate, and without difficulty be exaggerated by clustering center random initialized and remote points, however the algorithm is straightforward with low time difficulty, and can process the large data set rapidly. This paper suggests an enhanced K-means algorithm named PKM. PKM is based on similarity degree among data points made by cumulated K-means, and get the final clustering partition via fuzzy precise rate of clustering higher, and reduce the effects made by isolated points and random clustering center, at the same time, can be familiar with isolated points better. Experiments with analog information and genuine data make obvious its benefit.

Inactivation of the anterior cingulate reveals enhanced reliance on cortical networks for remote spatial memory retrieval after sequential memory processing.

One system consolidation model suggests that as time passes, ensembles of cortical neurons form strong connections to represent remote memories. In this model, the anterior cingulate cortex (ACC) serves as a cortical region that represents remote memories. However, there is debate as to whether remote spatial memories go through this systems consolidation process and come to rely on the ACC. The present experiment examined whether increasing the processing demand on the hippocampus, by sequential training on two spatial tasks, would more fully engage the ACC during retrieval of a remote spatial memory. In this scenario, inactivation of the ACC at a remote time point was hypothesized to produce a severe memory deficit if rats had been trained on two, sequential spatial tasks. Rats were trained on a water maze (WM) task only or a WM task followed by a radial arm maze task. A WM probe test was given recently or remotely to all rats. Prior to the probe test, rats received an injection of saline or muscimol into the ACC. A subtle deficit in probe performance was found at the remote time point in the group trained on only one spatial task and treated with muscimol. In the group trained on two spatial tasks and treated with muscimol, a subtle deficit in probe performance was noted at the recent time point and a substantial deficit in probe performance was observed at the remote time point. c-Fos labeling in the hippocampus revealed more labeling in the CA1 region in all remotely tested groups than recently tested groups. Findings suggest that spatial remote memories come to rely more fully on the ACC when hippocampal processing requirements are increased. Results also suggest continued involvement of the hippocampus in spatial memory retrieval along with a progressive strengthening of cortical connections as time progresses.

The most remote point method for the site selection of the future GGOS network

The Global Geodetic Observing System (GGOS) proposes 30–40 geodetic observatories as global infrastructure for the most accurate reference frame to monitor the global change. To reach this goal, several geodetic observatories have upgrade plans to become GGOS stations. Most initiatives are driven by national institutions following national interests. From a global perspective, the site distribution remains incomplete and the initiatives to improve this are up until now insufficient. This article is a contribution to answer the question on where to install new GGOS observatories and where to add observation techniques to existing observatories. It introduces the iterative most remote point (MRP) method for filling in the largest gaps in existing technique-specific networks. A spherical version of the Voronoi-diagram is used to pick the optimal location of the new observatory, but practical concerns determine its realistic location. Once chosen, the process is iterated. A quality and a homogeneity parameter of global networks measure the progress of improving the homogeneity of the global site distribution. This method is applied to the global networks of VGOS, and VGOS co-located with SLR to derive some clues about where additional observatory sites or additional observation techniques at existing observatories will improve the GGOS network configuration. With only six additional VGOS-stations, the homogeneity of the global VGOS-network could be significantly improved by more than $$45\,\%$$ . From the presented analysis, 25 known or new co-located VGOS and SLR sites are proposed as the future GGOS backbone: Colombo, Easter Island, Fairbanks, Fortaleza, Galapagos, GGAO, Hartebeesthoek, Honiara, Ibadan, Kokee Park, La Plata, Mauritius, McMurdo, Metsahovi, Ny Alesund, Riyadh, San Diego, Santa Maria, Shanghai, Syowa, Tahiti, Tristan de Cunha, Warkworth, Wettzell, and Yarragadee.

Marine litter distribution and density in European seas, from the shelves to deep basins.

Anthropogenic litter is present in all marine habitats, from beaches to the most remote points in the oceans. On the seafloor, marine litter, particularly plastic, can accumulate in high densities with deleterious consequences for its inhabitants. Yet, because of the high cost involved with sampling the seafloor, no large-scale assessment of distribution patterns was available to date. Here, we present data on litter distribution and density collected during 588 video and trawl surveys across 32 sites in European waters. We found litter to be present in the deepest areas and at locations as remote from land as the Charlie-Gibbs Fracture Zone across the Mid-Atlantic Ridge. The highest litter density occurs in submarine canyons, whilst the lowest density can be found on continental shelves and on ocean ridges. Plastic was the most prevalent litter item found on the seafloor. Litter from fishing activities (derelict fishing lines and nets) was particularly common on seamounts, banks, mounds and ocean ridges. Our results highlight the extent of the problem and the need for action to prevent increasing accumulation of litter in marine environments.

An adaptive augmented Lagrangian method for large-scale constrained optimization

We propose an augmented Lagrangian algorithm for solving large-scale constrained optimization problems. The novel feature of the algorithm is an adaptive update for the penalty parameter motivated by recently proposed techniques for exact penalty methods. This adaptive updating scheme greatly improves the overall performance of the algorithm without sacrificing the strengths of the core augmented Lagrangian framework, such as its ability to be implemented matrix-free. This is important as this feature of augmented Lagrangian methods is responsible for renewed interests in employing such methods for solving large-scale problems. We provide convergence results from remote starting points and illustrate by a set of numerical experiments that our method outperforms traditional augmented Lagrangian methods in terms of critical performance measures.

The impact of multiple memory formation on dendritic complexity in the hippocampus and anterior cingulate cortex assessed at recent and remote time points.

Consolidation processes, involving synaptic and systems level changes, are suggested to stabilize memories once they are formed. At the synaptic level, dendritic structural changes are associated with long-term memory storage. At the systems level, memory storage dynamics between the hippocampus and anterior cingulate cortex (ACC) may be influenced by the number of sequentially encoded memories. The present experiment utilized Golgi-Cox staining and neuron reconstruction to examine recent and remote structural changes in the hippocampus and ACC following training on three different behavioral procedures. Rats were trained on one hippocampal-dependent task only (a water maze task), two hippocampal-dependent tasks (a water maze task followed by a radial arm maze task), or one hippocampal-dependent and one non-hippocampal-dependent task (a water maze task followed by an operant conditioning task). Rats were euthanized recently or remotely. Brains underwent Golgi-Cox processing and neurons were reconstructed using Neurolucida software (MicroBrightField, Williston, VT, USA). Rats trained on two hippocampal-dependent tasks displayed increased dendritic complexity compared to control rats, in neurons examined in both the ACC and hippocampus at recent and remote time points. Importantly, this behavioral group showed consistent, significant structural differences in the ACC compared to the control group at the recent time point. These findings suggest that taxing the demand placed upon the hippocampus, by training rats on two hippocampal-dependent tasks, engages synaptic and systems consolidation processes in the ACC at an accelerated rate for recent and remote storage of spatial memories.

Future Distribution Feeder Protection Using Directional Overcurrent Elements

Distribution feeder protection could soon be complicated by non-radial flows of real and reactive power available from high penetration distributed generation and potentially from microgrids. Non-directional overcurrent protection may not provide necessary security and sensitivity for faults on remote points of the circuit. Directional supervision is necessary to set overcurrent pickups with adequate sensitivity for remote faults. Setting the directional element by traditional means provides a reliability risk at varying VAR flows within reach of specific types of distributed generation. This paper will demonstrate the limitations of non-directional overcurrent protection and the pitfalls of an improperly configured directional element. A unique solution using directional overcurrent elements further secured by a load encroachment function can solve these problems. This approach has been validated in renewable plant collector circuit protection applications over a wide range of operating conditions.