Primary Sensor Research Articles

IoT-Based Real-Time Aquaculture Health Monitoring System

Aquaculture fastest growing business worldwide especially in developing countries. Fisheries are marine species and required an oceanic environment where fisheries could grow and live naturally. Off-shore aquaculture businesses need a real-time water quality monitoring system. So, aquafarmers could maintain the required environment for a sustainable and profitable business. This work represents an IoT-based realtime health management system designed for aquaculture and considered the most required health metrics for aquaculture. The proposed system used four primary sensors: water level, temperature, pH, and dissolved oxygen. Sensors connected with microcontroller Arduino Uno R3 and ESP 8266 wi-fi module are used for data transmission to the IoT source ThingSpeak. The designed system could access online through the web interface and phone App for aquafarmers. The sensor data was accurate, and the system worked as designed.

Infrared Thermography Smart Sensor for the Condition Monitoring of Gearbox and Bearings Faults in Induction Motors.

The monitoring of machine conditions is very important from the viewpoints of productivity, economic benefits, and maintenance. Several techniques have been proposed in which sensors are the key to providing relevant information to verify the system. Recently, the smart sensor concept is common, in which the sensors are integrated with a data processing unit executing dedicated algorithms used to generate meaningful information about the system in situ. Additionally, infrared thermography has gained relevance in monitoring processes, since the new infrared cameras have more resolution, smaller dimensions, reliability, functionality, and lower costs. These units were firstly used as secondary elements in the condition monitoring of machines, but thanks to modern techniques for data processing, the infrared sensors can be used to give a first, or even a direct, diagnosis in a nonintrusive way in industrial applications. Therefore, in this manuscript, the structure and development of an infrared-thermography-based smart sensor for diagnosing faults in the elements associated with induction motors, such as rolling bearings and the gearbox, is described. The smart sensor structure includes five main parts: an infrared primary sensor, a preprocessing module, an image processing module, classification of faults, and a user interface. The infrared primary sensor considers a low-cost micro thermal camera for acquiring the thermal images. The processing modules and the classification module implement the data processing algorithms into digital development boards, enabling smart system characteristics. Finally, the interface module allows the final users to require the smart sensor to perform processing actions and data visualization, with the additional feature that the diagnosis report can be provided by the system. The smart sensor is validated in a real experimental test bench, demonstrating its capabilities in different case studies.

Cross-Axis Dynamic Field Compensation of Optically Pumped Magnetometer Arrays for MEG

We present dynamic field compensation (DFC), whereby three-axis field measurements from reference magnetometers are used to dynamically maintain null at the alkali vapor cells of an array of primary sensors that are proximal to a subject's scalp. Precision measurement of the magnetoencephalogram (MEG) by zero-field optically pumped magnetometer (OPM) sensors requires that sensor response is linear and sensor gain is constant over time. OPMs can be operated in open-loop mode, where the measured field is proportional to the output at the demodulated photodiode output, or in closed-loop, where on-board coils are dynamically driven to maintain the internal cell at zero field in the measurement direction. While OPMs can be operated in closed-loop mode along all three axes, this can increase sensor noise and poses engineering challenges. Uncompensated fluctuations in the ambient field along any statically nulled axes perturb the measured field by tipping the measurement axis and altering effective sensor gain – a phenomenon recently referred to as cross-axis projection error (CAPE). These errors are particularly problematic when OPMs are allowed to move in the remnant background field. Sensor gain-errors, if not mitigated, preclude precision measurements with OPMs operating in the presence of ambient field fluctuations within a typical MEG laboratory. In this manuscript, we present the cross-axis dynamic field compensation (DFC) method for maintaining zero field dynamically on all three axes of each sensor in an array of OPMs. Together, DFC and closed-loop operation strongly attenuate errors introduced by CAPE. This method was implemented by using three orthogonal reference sensors together with OPM electronics that permit driving each sensor's transverse field coils dynamically to maintain null field across its OPM measurement cell. These reference sensors can also be used for synthesizing 1st-gradient response to further reduce the effects of fluctuating ambient fields on measured brain activity and compensate for movement within a uniform field. We demonstrate that, using the DFC method, magnetic field measurement errors of less than 0.7% are easily achieved for an array of OPM sensors in the presence of ambient field perturbations of several nT.

Changes in physiological responses of OsCaM1-1 overexpression in the transgenic rice under dehydration stress.

Calmodulin, a primary calcium sensor in eukaryotes, binds calcium and regulates the activity of effector proteins in response to calcium signals that evoked in response to abiotic and biotic stress. To identify physiological responses associated with improved tolerance under dehydration stress that may be regulated by calmodulin in rice, the transgenic rice overexpressing OsCaM1-1, the control, and the wild-type KDML105 differing in their dehydration tolerance were compared 24 h after exposure to dehydration stress. The results demonstrated a greater increase in relative water content, relative growth rate, abscisic acid, photosynthetic pigment and proline contents, and antioxidant activities in the transgenic rice plants, whereas Na/K and Na/Ca ratio, lipid peroxidation, and electrolytic leakage decreased. The OsCaM1-1 gene overexpression in the transgenic rice showed greater tolerance to dehydration stress than non-transgenic rice, suggesting that OsCaM1-1 might play an important role in mitigating dehydration stress.

Ocular counter-roll is less affected in experienced versus novice space crew after long-duration spaceflight

Otoliths are the primary gravity sensors of the vestibular system and are responsible for the ocular counter-roll (OCR). This compensatory eye torsion ensures gaze stabilization and is sensitive to a head roll with respect to gravity and the Gravito-Inertial Acceleration vector during, e.g., centrifugation. To measure the effect of prolonged spaceflight on the otoliths, we quantified the OCR induced by off-axis centrifugation in a group of 27 cosmonauts in an upright position before and after their 6-month space mission to the International Space Station. We observed a significant decrease in OCR early postflight, larger for first-time compared to experienced flyers. We also found a significantly larger torsion for the inner eye, the eye closest to the rotation axis. Our results suggest that experienced cosmonauts have acquired the ability to adapt faster after G-transitions. These data provide a scientific basis for sending experienced cosmonauts on challenging missions that include multiple g-level transitions.

The Hippo-YAP/TAZ Signaling Pathway in Intestinal Self-Renewal and Regeneration After Injury.

The Hippo pathway and its downstream effectors, the transcriptional coactivators Yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ), control stem cell fate and cell proliferation and differentiation and are essential for tissue self-renewal and regeneration. YAP/TAZ are the core components of the Hippo pathway and they coregulate transcription when localized in the nucleus. The intestinal epithelium undergoes well-regulated self-renewal and regeneration programs to maintain the structural and functional integrity of the epithelial barrier. This prevents luminal pathogen attack, and facilitates daily nutrient absorption and immune balance. Inflammatory bowel disease (IBD) is characterized by chronic relapsing inflammation of the entire digestive tract. Impaired mucosal healing is a prominent biological feature of IBD. Intestinal self-renewal is primarily dependent on functional intestinal stem cells (ISCs), especially Lgr5+ crypt base columnar (CBC) cells and transient-amplifying (TA) cells in the crypt base. However, intestinal wound healing is a complicated process that is often associated with epithelial cells, and mesenchymal and immune cells in the mucosal microenvironment. Upon intestinal injury, nonproliferative cells rapidly migrate towards the wound bed to reseal the damaged epithelium, which is followed by cell proliferation and differentiation. YAP is generally localized in the nucleus of Lgr5+ CBC cells, where it transcriptionally regulates the expression of the ISC marker Lgr5 and plays an important role in intestinal self-renewal. YAP/TAZ are the primary mechanical sensors of the cellular microenvironment. Their functions include expanding progenitor and stem cell populations, reprogramming differentiated cells into a primitive state, and mediating the regenerative function of reserve stem cells. Thus, YAP/TAZ play extremely crucial roles in epithelial repair after damage. This review provides an overview of the Hippo–YAP/TAZ signaling pathway and the processes of intestinal self-renewal and regeneration. In particular, we summarize the roles of YAP/TAZ in the phases of intestinal self-renewal and regeneration to suggest a potential strategy for IBD treatment.

SynWoodScape: Synthetic Surround-View Fisheye Camera Dataset for Autonomous Driving

Surround-view cameras are a primary sensor for automated driving, used for near-field perception. It is one of the most commonly used sensors in commercial vehicles primarily used for parking visualization and automated parking. Four fisheye cameras with a <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$190^{\circ }$</tex-math></inline-formula> field of view cover the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$360^{\circ }$</tex-math></inline-formula> around the vehicle. Due to its high radial distortion, the standard algorithms do not extend easily. Previously, we released the first public fisheye surround-view dataset named WoodScape. In this work, we release a synthetic version of the surround-view dataset, covering many of its weaknesses and extending it. Firstly, it is not possible to obtain ground truth for pixel-wise optical flow and depth. Secondly, WoodScape did not have all four cameras annotated simultaneously in order to sample diverse frames. However, this means that multi-camera algorithms cannot be designed to obtain a unified output in birds-eye space, which is enabled in the new dataset. We implemented surround-view fisheye geometric projections in CARLA Simulator matching WoodScape’s configuration and created SynWoodScape. We release 80 k images from the synthetic dataset with annotations for 10+ tasks. We also release the baseline code and supporting scripts.

Research on Target Tracking for Robotic Fish Based on Low-Cost Scarce Sensing Information Fusion

Target tracking for underwater robots is always challenging, due to low-quality sensing information, information interference, and environmental disturbances. Traditional sensing methods for underwater target tracking include vision-based tracking, acoustic-based tracking, etc., but most of the adopted sensors are extremely expensive or complicated to achieve the mission. In this letter, we investigate the possibility of utilizing low-cost scarce sensing information for underwater target tracking through a robotic fish platform. First, we introduce the design and control system of the robotic fish platform. Instead of using cameras and other expensive sensors, we adopt low-cost infrared sensors as the primary sensors for the robotic fish, which can only detect the appearance of objects within the sensing range of each sensor. Second, we present a target tracking strategy based on the scarce sensing information and fusion by analyzing and combining the information of two adjacent consecutive moments of the sensors. Then, a centralized detection decision tree with fewer branches, fast convergence, and high purity is proposed. Finally, to verify our method, several sets of guided target tracking experiments are conducted. The experimental results show the effectiveness and robustness of the proposed target tracking strategy based on low-cost scarce sensing information fusion.

Sensing Mechanisms: Calcium Signaling Mediated Abiotic Stress in Plants.

Plants are exposed to various environmental stresses. The sensing of environmental cues and the transduction of stress signals into intracellular signaling are initial events in the cellular signaling network. As a second messenger, Ca2+ links environmental stimuli to different biological processes, such as growth, physiology, and sensing of and response to stress. An increase in intracellular calcium concentrations ([Ca2+]i) is a common event in most stress-induced signal transduction pathways. In recent years, significant progress has been made in research related to the early events of stress signaling in plants, particularly in the identification of primary stress sensors. This review highlights current advances that are beginning to elucidate the mechanisms by which abiotic environmental cues are sensed via Ca2+ signals. Additionally, this review discusses important questions about the integration of the sensing of multiple stress conditions and subsequent signaling responses that need to be addressed in the future.

Structure-function analysis of the AMPK activator SC4 and identification of a potent pan AMPK activator.

The AMP-activated protein kinase (AMPK) αβγ heterotrimer is a primary cellular energy sensor and central regulator of energy homeostasis. Activating skeletal muscle AMPK with small molecule drugs improves glucose uptake and provides an opportunity for new strategies to treat type 2 diabetes and insulin resistance, with recent genetic and pharmacological studies indicating the α2β2γ1 isoform combination as the heterotrimer complex primarily responsible. With the goal of developing α2β2-specific activators, here we perform structure/function analysis of the 2-hydroxybiphenyl group of SC4, an activator with tendency for α2-selectivity that is also capable of potently activating β2 complexes. Substitution of the LHS 2-hydroxyphenyl group with polar-substituted cyclohexene-based probes resulted in two AMPK agonists, MSG010 and MSG011, which did not display α2-selectivity when screened against a panel of AMPK complexes. By radiolabel kinase assay, MSG010 and MSG011 activated α2β2γ1 AMPK with one order of magnitude greater potency than the pan AMPK activator MK-8722. A crystal structure of MSG011 complexed to AMPK α2β1γ1 revealed a similar binding mode to SC4 and the potential importance of an interaction between the SC4 2-hydroxyl group and α2-Lys31 for directing α2-selectivity. MSG011 induced robust AMPK signalling in mouse primary hepatocytes and commonly used cell lines, and in most cases this occurred in the absence of changes in phosphorylation of the kinase activation loop residue α-Thr172, a classical marker of AMP-induced AMPK activity. These findings will guide future design of α2β2-selective AMPK activators, that we hypothesise may avoid off-target complications associated with indiscriminate activation of AMPK throughout the body.

Structures of a mammalian TRPM8 in closed state

Transient receptor potential melastatin 8 (TRPM8) channel is a Ca2+-permeable non-selective cation channel that acts as the primary cold sensor in humans. TRPM8 is also activated by ligands such as menthol, icilin, and phosphatidylinositol 4,5-bisphosphate (PIP2), and desensitized by Ca2+. Here we have determined electron cryo-microscopy structures of mouse TRPM8 in the absence of ligand, and in the presence of Ca2+ and icilin at 2.5–3.2 Å resolution. The ligand-free state TRPM8 structure represents the full-length structure of mammalian TRPM8 channels with a canonical S4-S5 linker and the clearly resolved selectivity filter and outer pore loop. TRPM8 has a short but wide selectivity filter which may account for its permeability to hydrated Ca2+. Ca2+ and icilin bind in the cytosolic-facing cavity of the voltage-sensing-like domain of TRPM8 but induce little conformational change. All the ligand-bound TRPM8 structures adopt the same closed conformation as the ligand-free structure. This study reveals the overall architecture of mouse TRPM8 and the structural basis for its ligand recognition.

РЕАЛИЗАЦИЯ РАСПРЕДЕЛЕННЫХ ВЫЧИСЛЕНИЙ НА ОТЕЧЕСТВЕННЫХ МИКРОПРОЦЕССОРНЫХ УСТРОЙСТВАХ

The aim of the work is to create a productive computing device for a strapdown inertial navigationsystem (SINS) of a ground-based robotic complex (RTC) on a domestic element base.A formal description of the typical sufficient functions performed by SINS is given and the basicprinciples of the algorithms are described from the point of view of the requirements for computingresources. A description of domestic microcontrollers available on the market and a comparison withthe closest foreign analogue are given. The results of the prototyping carried out showed the fundamentalpossibility, but the low prospects of creating computing devices on a single microcontroller.In this regard, technical proposals were developed and implemented to increase the computing powerby means of building the architecture of a multiprocessor computer. As a result, it was necessaryto develop special approaches to the design of algorithms and software. The organization of distributedcomputing is one of the most optimal methods for ensuring the calculation of functioning algorithms.The introduction of additional microprocessors into the calculator circuit made it possible notonly to increase the computing power, but also to introduce additional interfaces for interaction withboth the consumer and primary information sensors. The proposed variant of the distribution of SINSoperation algorithms made it possible to create a reserve for the development prospects and systemscalability. The most resource-intensive algorithm is the calculation of inertial coordinates, implementedas an iterative calculation for determining the latitude component of the location. Also, theperformance margin may allow the implementation of additional adaptive algorithms for filteringand processing data based on the results of testing and operation of a ground moving object.The choice of on-board exchange interface between controllers is substantiated and its practicalapplication is described. The creation of a closed loop of information exchange made it possible toimplement additional parallel calculations of secondary information and to calculate an autonomousreckoning of the object's location coordinates. The described technical solutions can be used in thedesign of embedded calculators for objects for various purposes operating on the basis of hard logic.As the main drawback of the presented approach to designing a calculator, one can designate a limitedfunctionality when working with ROMs.

NQRELoc: AP Selection via Nonuniform Quantization RSSI Entropy for Indoor Localization

Received signal strength indicator (RSSI) of WiFi access point (AP) is a primary sensor data used for indoor fingerprint localization. User sends its online RSSI to server to estimate its position by matching with RSSI fingerprints database which built in the offline phase. An important goal of indoor fingerprint localization is to increase the accuracy while reduce the storage cost. Meanwhile, APs perform different effects on target estimation and mapping metric in RSSI fingerprint localization. In this paper, a novel localization model based on the nonuniform quantization RSSI entropy (NQRELoc) is proposed to address these problems. First, to select the APs that contribute more to the localization, the nonuniform quantization RSSI entropy (NQRE) is introduced to quantify AP’s discernibility and select APs whose signals show sufficient differentiation to construct an offline fingerprints database. Then, the entropy-weighted euclidean distance (EWED) is used as a metric to measure the similarity of online RSSI vectors and offline RPs fingerprints. Finally, NQRELoc locates the target by the improved entropy-weighted K nearest neighbor (IEWKNN) algorithm, which takes the APs effect into target estimation. To validate the proposed algorithm, a large scale of experiments and simulations are implemented. The results demonstrate that NQRELoc can not only reduce the storage overhead but also improve the positioning accuracy compared to the other existing techniques.

Dynamic O-GlcNAcylation coordinates ferritinophagy and mitophagy to activate ferroptosis

Ferroptosis is a regulated iron-dependent cell death characterized by the accumulation of lipid peroxidation. A myriad of facets linking amino acid, lipid, redox, and iron metabolisms were found to drive or to suppress the execution of ferroptosis. However, how the cells decipher the diverse pro-ferroptotic stress to activate ferroptosis remains elusive. Here, we report that protein O-GlcNAcylation, the primary nutrient sensor of glucose flux, orchestrates both ferritinophagy and mitophagy for ferroptosis. Following the treatment of ferroptosis stimuli such as RSL3, a commonly used ferroptosis inducer, there exists a biphasic change of protein O-GlcNAcylation to modulate ferroptosis. Pharmacological or genetic inhibition of O-GlcNAcylation promoted ferritinophagy, resulting in the accumulation of labile iron towards mitochondria. Inhibition of O-GlcNAcylation resulted in mitochondria fragmentation and enhanced mitophagy, providing an additional source of labile iron and rendering the cell more sensitive to ferroptosis. Mechanistically, we found that de-O-GlcNAcylation of the ferritin heavy chain at S179 promoted its interaction with NCOA4, the ferritinophagy receptor, thereby accumulating labile iron for ferroptosis. Our findings reveal a previously uncharacterized link of dynamic O-GlcNAcylation with iron metabolism and decision-making for ferroptosis, thus offering potential therapeutic intervention for fighting disease.

Inhalation Exposure to Airborne PM2.5Induces Integrated Organelle Stress Response in the Liver

Air pollution is a sustained problem of public health for the general population. Accumulating evidence has confirmed a significant association between exposure to fine ambient particulate matter with aerodynamic diameters &lt; 2.5 μm (PM2.5) and the increase of morbidity and mortality associated with cardiovascular and metabolic diseases. Chronic inflammation and dysregulated energy metabolism have been identified as the driving force of the PM2.5‐caused pathogenesis. However, a precise understanding of the molecular and cellular mechanisms by which PM2.5induces inflammatory stress responses and impairs energy homeostasis remains elusive. Research in our laboratory has addressed the mechanistic basis underlying the pathophysiologic effects of PM2.5exposure on liver and adipose tissues with mouse models under inhalation exposure to environmentally relevant PM2.5. Proteomics analysis with PM2.5‐exposed mouse liver tissues indicated that mitochondria and endoplasmic reticulum (ER) are the most sensitive organelles in transducing signaling cascades upon PM2.5stimulation. Further investigation revealed that inhalation exposure to PM2.5induces an integrated ER stress and mitochondrial stress response in mouse livers. Under PM2.5exposure, the ER and mitochondria interact and build up a platform through Mitochondria‐Associated Membranes (MAMs) to augment an integrated inflammatory stress response, mediated through the primary ER stress sensor IRE1α and Toll‐like receptor (TLR) 2 and 4. This integrated organelle stress response pathway promoted non‐alcoholic steatohepatitis (NASH), characterized by hepatic inflammation, steatosis and fibrogenesis, hepatic glycogen depletion, and insulin resistance in PM2.5‐exposed mice. Disruption of MAMs by knockdown of the MAM‐residing ER chaperone Sigma‐1 Receptor (Sig‐1R) or mitofusin (MNF2) in Kupffer cells or hepatocytes suppressed PM2.5‐induced NASH and insulin resistance in mice. Together, our studies suggested that exposure to airborne PM2.5pollution activates an integrated ER and mitochondrial stress response in the liver, which promotes NASH, disrupts energy homeostasis, and impairs insulin signaling associated with the development of metabolic syndrome. These findings provide significant insights into the hepatic pathways underlying PM2.5‐triggered liver pathology, and have important implications in the understanding, prevention, and treatment of air pollution‐associated metabolic disease.

Allosteric coupling between transmembrane segment 4 and the selectivity filter of TALK1 potassium channels regulates their gating by extracellular pH

Opening of two-pore domain K+ channels (K2Ps) is regulated by various external cues, such as pH, membrane tension, or temperature, which allosterically modulate the selectivity filter (SF) gate. However, how these cues cause conformational changes in the SF of some K2P channels remains unclear. Herein, we investigate the mechanisms by which extracellular pH affects gating in an alkaline-activated K2P channel, TALK1, using electrophysiology and molecular dynamics (MD) simulations. We show that R233, located at the N-terminal end of transmembrane segment 4, is the primary pHo sensor. This residue distally regulates the orientation of the carbonyl group at the S1 potassium-binding site through an interacting network composed of residues on transmembrane segment 4, the pore helix domain 1, and the SF. Moreover, in the presence of divalent cations, we found the acidic pH-activated R233E mutant recapitulates the network interactions of protonated R233. Intriguingly, our data further suggested stochastic coupling between R233 and the SF gate, which can be described by an allosteric gating model. We propose that this allosteric model could predict the hybrid pH sensitivity in heterodimeric channels with alkaline-activated and acidic-activated K2P subunits.

Materials, Preparation Strategies, and Wearable Sensor Applications of Conductive Fibers: A Review.

The recent advances in wearable sensors and intelligent human–machine interfaces have sparked a great many interests in conductive fibers owing to their high conductivity, light weight, good flexibility, and durability. As one of the most impressive materials for wearable sensors, conductive fibers can be made from a variety of raw sources via diverse preparation strategies. Herein, to offer a comprehensive understanding of conductive fibers, we present an overview of the recent progress in the materials, the preparation strategies, and the wearable sensor applications related. Firstly, the three types of conductive fibers, including metal-based, carbon-based, and polymer-based, are summarized in terms of their principal material composition. Then, various preparation strategies of conductive fibers are established. Next, the primary wearable sensors made of conductive fibers are illustrated in detail. Finally, a robust outlook on conductive fibers and their wearable sensor applications are addressed.

MEASURES AND MEANS TO IMPROVE THE ENERGY EFFICIENCY OF FOOD PRODUCTION

Improving the energy efficiency of modern enterprises, including the food industry as one of the priorities for the life support of the population, is of strategic importance for Ukraine. The purpose of the study is an analysis of the energy-saving potential of food industry enterprises and the search for ways to reduce the energy intensity of technological processes, devices, and equipment, as well as transmission heat losses of buildings and structures. For field tests of industrial and technological objects, a combined thermal imaging and thermometric research methodology was chosen, which combines thermal imaging of characteristic thermal zones to detect anomalous areas and contact measurements of thermophysical parameters in these zones. A computerised information and measuring system equipped with a set of primary sensors of temperature, heat flux, humidity, etc. was used for long-term monitoring of thermophysical parameters simultaneously at different sites of the facilities. As a result, an array of data was obtained and processed, the parameters of complex convective and radiation heat transfer were calculated, and the heat transfer resistance was determined, which allows assessing the degree of danger of the detected thermal anomalies and developing measures for thermal modernisation of facilities using modern thermal insulation materials. Reduction of heat loss in production processes is also achieved by organising high-quality thermal insulation of technological apparatuses, pipelines and refrigeration equipment. The main parameter for selecting the required material is its low thermal conductivity in the operating temperature range of the equipment. For the effective heat insulator selection, the thermal conductivity of a number of popular materials of world-famous manufacturers was studied based on the certified information-measuring system of Ukrainian design by the stationary plate method with the use of heat flux and temperature sensors. The thermophysical parameters of heat-insulating materials in the range of 0.02...0.045 W/(m·K) were estimated and thereby revealed the thermal conductivity of materials with a closed microporous structure to be half that of fibrous ones and not dependent on the density of the material, which makes them the best option for high-quality insulation of buildings and equipment of food production

The New Method of Active SLAM for Mapping Using LiDAR

In this article, we propose a new approach to addressing the issue of active SLAM. In this design, we used the already functional SLAM algorithm, which we modified for our case. Matlab was used as the main software tool. All proposed methods were experimentally verified on a mobile robotic system. We used LiDAR as the primary sensor. After mapping the environment, we created a grid map. The grid map may be used for the navigation of the mobile robotic system, but the navigation and control of the mobile robotic system are not involved in this article. The result of the whole process is an autonomous mapping of the environment.

Crucial role and mechanism of transcription-coupled DNA repair in bacteria.

Transcription-coupled DNA repair (TCR) is presumed to be a minor sub-pathway of nucleotide excision repair (NER) in bacteria. Global genomic repair is thought to perform the bulk of repair independently of transcription. TCR is also believed to be mediated exclusively by Mfd-a DNA translocase of a marginal NER phenotype1-3. Here we combined in cellulo cross-linking mass spectrometry with structural, biochemical and genetic approaches to map the interactions within the TCR complex (TCRC) and to determine the actual sequence of events that leads to NER in vivo. We show that RNA polymerase (RNAP) serves as the primary sensor of DNA damage and acts as a platform for the recruitment of NER enzymes. UvrA and UvrD associate with RNAP continuously, forming a surveillance pre-TCRC. In response to DNA damage, pre-TCRC recruits a second UvrD monomer to form a helicase-competent UvrD dimer that promotes backtracking of the TCRC. The weakening of UvrD-RNAP interactions renders cells sensitive to genotoxic stress. TCRC then recruits a second UvrA molecule and UvrB to initiate the repair process. Contrary to the conventional view, we show that TCR accounts for the vast majority of chromosomal repair events; that is, TCR thoroughly dominates over global genomic repair. We also show that TCR is largely independent of Mfd. We propose that Mfd has an indirect role in this process: it participates in removing obstructive RNAPs in front of TCRCs and also in recovering TCRCs from backtracking after repair has been completed.