Learning enhances encoding of time and temporal surprise in primary sensory cortex

Primary sensory cortex has long been believed to play a straightforward role in the initial processing of sensory information. Yet, the superficial layers of cortex overall are sparsely active, even during sensory stimulation; moreover, cortical activity is influenced by other modalities, task context, reward, and behavioral state. Our study demonstrates that reinforcement learning dramatically alters representations among longitudinally imaged neurons in superficial layers of mouse primary somatosensory cortex. Learning an object detection task recruits previously unresponsive neurons, enlarging the neuronal population sensitive to touch and behavioral choice. In contrast, cortical responses decrease upon repeated exposure to unrewarded stimuli. Moreover, training improved population encoding of the passage of time, and unexpected deviations in trial timing elicited even stronger responses than touch did. In conclusion, the superficial layers of sensory cortex exhibit a high degree of learning-dependent plasticity and are strongly modulated by non-sensory but behaviorally-relevant features, such as timing and surprise.

A Novel Method for Layover Detection in Mountainous Areas with SAR Images

It is well known that there are geometric distortions in synthetic aperture radar (SAR) images when the terrain undulates. Layover is the most common one, which brings challenges to the application of SAR remote sensing. This study proposes a novel detection method that is mainly aimed at the layover caused by mountains and can be performed with only medium-resolution SAR images and no other auxiliary data. The detection includes the following four stages: initial processing, difference image calculation and rough and fine layover detection. Initial processing mainly obtains the potential layover areas, which are mixed with the built-up areas after classification. Additionally, according to the analysis of the backscatter coefficient (BC) of various ground objects with different polarization images, the layover areas are detected step-by-step from the mixed areas, in which the region-based FCM segmentation algorithm and spatial relationship criteria are used. Taking the Danjiangkou Reservoir area as the study area, the relevant experiments with Sentinel-1A SAR images were conducted. The quantitative analysis of detection results adopted the figure of merit (FoM), and the highest accuracy was up to 87.6% of one selected validation region. Experiments in the South Taihang area also showed the satisfactory effect of layover detection, and the values of FoM were all above 85%. These results show that the proposed method can do well in the layover detection caused by mountains. Its simplicity and effectiveness are helpful in removing the influence of layover on SAR image applications to a certain extent and improving the development of SAR remote sensing technology.

Effect of Varying Initial Processing Temperature on Mechanical Properties of Carbon Epoxy Composites

Use of composite materials for structural application has greatly flourished in last three decades. Mechanical properties of carbon composite are largely dependent on the processing parameters like processing temperature, compaction pressure, resin flow and fiber orientation. Processing temperature has an important and decisive role in defining the properties of the composites and absence of proper temperature can cause reduced mechanical properties and defects like wrinkles and voids. This study focuses on varying the initial processing temperature for carbon laminates and documents the effect on mechanical properties of the composite produced. The testing range of temperature was specified by the choice of resin. It was found that the mechanical properties like tensile, bending and shear strength increased non-linearly with increasing initial temperature of processing. Increase of fiber volume fraction, fiber weight fraction and density were observed which along with better resin distribution, resin flow and increased laminate compaction can be attributed as key reasons of increased mechanical properties

How the use of segmentation signs in compound reading affects reading behavior: an eye-tracking study

Two eye-tracking experiments were conducted to investigate the effects of visual segmenta-tion, complexity, and context on the cognitive processing of compounds in German Easy Language. By presenting compounds in different boundary conditions, we determined whether a segmentation cue facilitates the processing of compounds presented with and without contextual information. The study was conducted with unimpaired adults and with hearing-impaired pupils, representing one of the target groups of Easy Language. The results indicate that visual segmentation facilitates processing of compounds for pupils with low literacy skills. However, they only benefit from segmentation when morpheme boundaries are marked in a subtle way, i.e., without strikingly deviating from the standard version. Pupils with higher literacy skills and unimpaired adults do not profit from segmentation. Even though hyphenation slows down compound processing for unimpaired readers, initial processing advantages of hyphenated over concatenated compounds emerged, which is explained by the fact that hyphenation forces a morpheme-based access and enables fast recognition of the compound’s first constituent. However, it hinders readers from accessing the compound via the direct route and thus slows down the processing of the compound as a whole. Furthermore, unimpaired readers and hearing-impaired pupils process compounds faster when presented with context.

Role of 53BP1 in end protection and DNA synthesis at DNA breaks

Double-strand break (DSB) repair choice is greatly influenced by the initial processing of DNA ends. 53BP1 limits the formation of recombinogenic single-strand DNA (ssDNA) in BRCA1-deficient cells, leading to defects in homologous recombination (HR). However, the exact mechanisms by which 53BP1 inhibits DSB resection remain unclear. Previous studies have identified two potential pathways: protection against DNA2/EXO1 exonucleases presumably through the Shieldin (SHLD) complex binding to ssDNA, and localized DNA synthesis through the CTC1-STN1-TEN1 (CST) and DNA polymerase α (Polα) to counteract resection. Using a combinatorial approach of END-seq, SAR-seq, and RPA ChIP-seq, we directly assessed the extent of resection, DNA synthesis, and ssDNA, respectively, at restriction enzyme-induced DSBs. We show that, in the presence of 53BP1, Polα-dependent DNA synthesis reduces the fraction of resected DSBs and the resection lengths in G0/G1, supporting a previous model that fill-in synthesis can limit the extent of resection. However, in the absence of 53BP1, Polα activity is sustained on ssDNA yet does not substantially counter resection. In contrast, EXO1 nuclease activity is essential for hyperresection in the absence of 53BP1. Thus, Polα-mediated fill-in partially limits resection in the presence of 53BP1 but cannot counter extensive hyperresection due to the loss of 53BP1 exonuclease blockade. These data provide the first nucleotide mapping of DNA synthesis at resected DSBs and provide insight into the relationship between fill-in polymerases and resection exonucleases.

An efficient polymer cocktail-based transportation method for cartilage tissue, yielding chondrocytes with enhanced hyaline cartilage expression during in vitro culturing

Chondrocytes are used in cell-based therapies such as autologous chondrocyte implantation (ACI) and matrix-associated cartilage implantation (MACI). To transport the cartilage tissue to the laboratory for in vitro culturing, phosphate-buffered saline (PBS), Euro-Collins solution (ECS) and Dulbecco Modified Eagle Medium (DMEM) are commonly employed at 4-8 deg C. In this study, eight samples of human cartilage biopsy tissues from elderly patients with severe osteoarthritis undergoing arthroscopy, which would otherwise have been discarded, were used. The cartilage tissue samples were compared to assess the cell yield between two transportation groups: i) a thermo-reversible gelation polymer (TGP) based method without cool preservation (~25 deg C) and ii) ECS transport at 4 deg C. These samples were subjected to in vitro culture in a two-dimensional (2D) monolayer for two weeks and subsequently in a three-dimensional (3D) TGP scaffold for six weeks. The cell count obtained from the tissues transported in TGP was higher (0.2 million cells) than those transported in ECS (0.08 million cells) both after initial processing and after in vitro culturing for 2 weeks in 2D (18 million cells compared with 10 million cells). In addition, mRNA quantification demonstrated significantly higher expression of Col2a1 and SOX-9 in 3D-TGP cultured cells and lower expression of COL1a1 in RT-PCR, characteristic of the hyaline cartilage phenotype, than in 2D culture. This study confirms that the TGP cocktail is suitable for both the transport of human cartilage tissue and for in vitro culturing to yield better-quality cells for use in regenerative therapies.

THE DRIVERS AND BARRIERS OF GREEN SUPPLY CHAIN MANAGEMENT IMPLEMENTATION: A REVIEW

Due to environmental degradation such as climate change, increased CO2 and GHG emission and all other problems threatening the world and its existence. Firms now are forced to think about integrating environmental thinking into their business operations in order to satisfy their stakeholders. Therefore, several organizations start developing environmental management strategies such as green practices overall their business operations, and since the supply chain concerns the product from its initial processing of raw material until the delivery to the customer there has been an emergency to integrate environmental thinking within this function. This paper aims to review the literature on the drivers and barriers influencing GSCM implementation. A total of 60 elements that englobe 28 drivers, and 32 barriers were identified from the selected literature where only the highest weightage factors are discussed. As results, Financial and cost related factors, Customers and Regulatory related factors seemed to behave simultaneously in both directions.

A Novel Approach to Spoken Arabic Number Recognition Based on Developed Ant Lion Algorithm

Intelligent spoken system is constructed to recognize numbers spoken in Arabic language by different people. Series of operations are performed on audio sound file as pre-processing stages. A novel approach is applied to extract features of audio files called Max Mean Log to reduce audio file dimensions in an efficient manner. Several stages of initial processing are used to prepare the file for the next step of the recognition process. The recognition process begins with the use of Antlion’s advanced intelligence algorithm to determine the type of the spoken number in Arabic and later convert it to a visual text that represents the value of the spoken number. The current proposal method is relatively fast and very effective. The percentage of recognizing numbers spoken by the proposed algorithm is 99%. For 1,800 different audio files, the error rate was 1%. Additional 40 audio files were used that are different from people’s original dataset. Due to an additional examination of the system and its ability to recognize the audio file, the rate of discrimination for such files was 72.5%.

A New Approach in Query Expansion Methods for Improving Information Retrieval

This research develops a new approach to query expansion by integrating Association Rules (AR) and Ontology. In the proposed approach, there are several steps to expand the query, namely (1) the document retrieval step; (2) the step of query expansion using AR; (3) the step of query expansion using Ontology. In the initial step, the system retrieved the top documents via the user's initial query. Next is the initial processing step (stopword removal, POS Tagging, TF-IDF). Then do a Frequent Itemset (FI) search from the list of terms generated from the previous step using FP-Growth. The association rules search by using the results of FI. The output from the AR step expanded using Ontology. The results of the expansion with Ontology use as new queries. The dataset used is a collection of learning documents. Ten queries used for the testing, the test results are measured by three measuring devices, namely recall, precision, and f-measure. Based on testing and analysis results, integrating AR and Ontology can increase the relevance of documents with the value of recall, precision, and f-measure by 87.28, 79.07, and 82.85.

The Foreground Bias: Initial Scene Representations Across the Depth Plane

When you walk into a large room, you perceive visual information that is both close to you in depth and farther in the background. Here, we investigated how initial scene representations are affected by information across depth. We examined the role of background and foreground information on scene gist by using chimera scenes (images with a foreground and background from different scene categories). Across three experiments, we found a foreground bias: Information in the foreground initially had a strong influence on the interpretation of the scene. This bias persisted when the initial fixation position was on the scene background and when the task was changed to emphasize scene information. We concluded that the foreground bias arises from initial processing of scenes for understanding and suggests that scene information closer to the observer is initially prioritized. We discuss the implications for theories of scene and depth perception.