Pyramidal Layer Research Articles

The Digital Markets Act: A partial solution to antitrust’s remedy problem

Antitrust remedies in digital markets have shown little effectiveness. The Digital Markets Act (DMA) offers a partial solution by establishing a multi-level remedial pyramid that addresses several of the challenges the Commission faced when remedying antitrust infringements. At the base of this pyramid are the DMA’s obligations, which embed ex ante remedies that are faster and more prescriptive than antitrust remedies. The second level consists of regulatory dialogue, an open and iterative specification procedure that can mitigate information asymmetries and future-proof remedies. The third level is the non-compliance procedure, which complements the regulatory dialogue. At the pyramid’s apex is the systematic non-compliance procedure. It empowers the Commission to impose ex post remedies, which can be more forceful than their EU competition law counterparts. Although the DMA enhances the Commission’s remedial process and powers compared to EU competition law, it is crucial for the Commission to exercise its authority judiciously. The Commission’s focus should be on the intermediate layers of the remedial pyramid, particularly the regulatory dialogue.

Histomorphological and Comparative Study for Cerebral Cortex Thickness and Length of Brain in Neonate of Human (Statistical and histomorphological investication)

Twenty five specimens of tissue brain at age 1-28 days after birth, were used, put in 10% formalin for fixation , then excised from the skull, for twenty hour . Samples of 0.5 cm3 thickness from frontal ,parietal ,temporal and occipital lobes are put in the fixative formalin ten percentage and then obtained for histological technique and finally stained by (H&E). The presented results were based on the analysis of a samples of 25 neonatal corps. The samples were further classified into 2 age groups, first 2 weeks of life with a sample size of 10 brain and the second was 15-28 days of age with a sample size of 15 brain. The antero-posterior cranial length was measured. In addition of the thickness of each of the 4 brain lobes were measured in triplicates and the mean of these 3 samples repeated measurements was used for comparison. The mean frontal lobe thickness ranged between 2.42 to 3.72 mm in the first group or younger age and between 3.11 to 4.28 mm in the second group or older age. The mean of frontal lobe thickness was significantly higher in older age (3.67 mm) compared to younger age (3.05mm). The mean difference in frontal lobe thickness of (0.62 mm) was evaluated as a large difference (Cohen’s d > 0.8). The histological result demonstrated that the parietal and frontal lobes were lo ated at the anterior and lateral cerebral hemisphere and the brain cortex composed by six layers and these are outer molecular and granular . external and inner pyramidal neurons external pyramidal, internal granular, internal pyramidal and polymorphic layers.

Probiotics by Modulating Gut-Brain Axis Together With Brivaracetam Mitigate Seizure Progression, Behavioral Incongruities, and Prevented Neurodegeneration in Pentylenetetrazole-Kindled Mice.

The microbiota-gut-brain axis (MGBA) is a central nexus that integrates higher cognitive and emotional centers of the central nervous system (CNS) within the intricate functioning of the intestine. Accumulating evidence suggests that dysbiosis in the taxonomic diversity of gut flora plays a salient role in the progression of epilepsy and comorbid secondary complications. In the current study, we investigated the impact of long-term oral bacteriotherapy (probiotics; 10 mL/kg; 109 colony-forming unit/ml) as an adjunctive treatment intervention with brivaracetam (BRV; 10 mg/kg) over 21 days on pentylenetetrazole (PTZ) induced augmented epileptic response and associated electrographical and behavioral perturbations in mice. Moreover, we also unveiled antioxidant capacity and histopathologic changes in treated versus non-treated animals. Results revealed combination increases seizure threshold and prevented high ictal spiking. Additionally, it alleviated PTZ-induced neuropsychiatric disturbances such as anxiety and depressive-like phenotype along with cognitive deficits. Furthermore, dual therapy prompted physiological oxidant/antioxidant balance as evidenced by increased activity of antioxidant enzymes (SOD and catalase) and reduced levels of oxidative stressor (MDA). This therapeutic intervention with commensal species suppressed network-driven neuroinflammation and preserved normal cytoarchitecture with intact morphology in the pyramidal layers of cornu ammonis (CA1 and CA3). Our study provides supporting evidence for the use of probiotics as adjunctive therapy with anti-seizure medications to modulate epileptogenic processes and related multimorbidities, particularly in individuals with drug-resistant seizures.

Hippocampal recording with a soft microelectrode array in a cranial window imaging scheme: a validation study

The hippocampus has a crucial role in the formation, consolidation and recall of memories as well as in navigation related processes. These functions are in the focus of neuroscience and different disciplines have contributed to this research field for decades. Two-photon imaging in awake animals is a valuable new aspect for these observations, especially when it is supported by electrophysiology. In this study, we applied high speed two-photon hippocampal imaging through a chronically implanted, soft, transparent microelectrode (STM) device incorporated into a cranial window chamber in awake mice. We monitored the impedance of the recording sites over the course of the experiments to observe long-term changes in recording quality. The large-scale ipsilateral local field potential (LFP) recordings from the dorsal hippocampus provided reliable sharp wave-ripples (SPW-Rs), multi-unit activity (MUA) and single-unit activity (SUA) for up to two months. Calcium imaging of GCaMP6f. labeled cells from the CA1 pyramidal layer under the transparent device was possible even after six months in thy1-GCaMP6f. transgenic mice. We investigated the immune response with GFAP staining after the end of the long-term experiments. Based on our results, this dedicated transparent electrode device proved to be suitable for simultaneous two-photon imaging and large-scale electrophysiological measurements in chronic experiments in mice.

Lightweight mask R-CNN for instance segmentation and particle physical property analysis in multiphase flow

A lightweight Mask R-CNN instance segmentation model was developed here to analyze particle size and shape accurately and quickly. Firstly, a hybrid Depthwise Dilated Convolutional Network (DDNet) is proposed, and the feature pyramid layers and the shared convolutional layers of the region proposal network are simplified, reducing the model complexity while ensuring robust feature extraction capabilities. Then, segmentation accuracy is significantly improved without sacrificing computational speed and performance by introducing the Dice loss function and clustering algorithm. Experimental results show that the model parameters are significantly reduced by 49.46%, and the segmentation speed increases from 2.15 FPS (frames per second) to 5.88 FPS. Meanwhile, the segmentation accuracy (AP50) increased from 90.56% to 91.21%. In addition, it was proven that the particle size distribution and shape could be analyzed accurately and rapidly with the proposed model, providing essential information for multiphase flow process optimization and equipment design in industrial applications.

Distribution of lipid droplets in hippocampal neurons and microglia: impact of diabetes and exercise.

Neuroinflammation, aging, and neurodegenerative disorders are associated with excessive accumulation of neutral lipids in lipid droplets (LDs) in microglia. Type 2 diabetes mellitus (T2DM) may cause neuroinflammation and is a risk factor for neurodegenerative disorders. Here, we show that hippocampal pyramidal neurons contain smaller, more abundant LDs than their neighboring microglia. The density of LDs varied between pyramidal cells in adjacent subregions, with CA3 neurons containing more LDs than CA1 neurons. Within the CA3 region, a gradual increase in the LD content along the pyramidal layer from the hilus toward CA2 was observed. Interestingly, the high neuronal LD content correlated with less ramified microglial morphotypes. Using the db/db model of T2DM, we demonstrated that diabetes increased the number of LDs per microglial cell without affecting the neuronal LD density. High-intensity interval exercise induced smaller changes in the number of LDs in microglia but was not sufficient to counteract the diabetes-induced changes in LD accumulation. The changes observed in response to T2DM may contribute to the cerebral effects of T2DM and provide a mechanistic link between T2DM and neurodegenerative disorders.

Therapeutic potential of mesenchymal stromal cells on morphological parameters in the hippocampus of rats with brain ischemia-reperfusion modeling

Ischemic stroke is an extremely important pathology with high mortality, in which more than 50 % of patients with occlusion of the main vessels remain disabled, despite early reperfusion therapy by thrombolysis or thrombectomy. As part of the regenerative strategy, stem cell transplantation in ischemic stroke became a new impetus. Cell therapy with the use of mesenchymal stromal cells demonstrated encouraging results regarding endogenous mechanisms of neuroregeneration in response to ischemic damage to brain structures. The aim of the research is to study the influence of mesenchymal stromal cells of various genesis, lysate of mesenchymal stromal cells obtained from Wharton’s jelly umbilical cord and citicoline on the dynamics of morphological changes in the hippocampal CA1 region of rats with acute cerebral ischemia-reperfusion according to light microscopy and micromorphometry data. The experiment was carried out using 200 male Wistar rats, which were subjected to ischemia-reperfusion by reversible 20-minute bilateral occlusion of the internal carotid arteries. Animals with modeled pathology were intravenously transplanted with mesenchymal stromal cells of various genesis (from Wharton’s jelly of the human umbilical cord, human and rat adipose tissue), and rat embryonic fibroblasts, lysate of mesenchymal stromal cells and citicoline were injected. Histological analysis of rat brain sections was performed on the 7th and 14th day of the experiment. Statistical analysis was performed using “Statistica 6.0” (StatSoft® Snc, USA). The significance of differences was assessed using the Student’s t-test and the nonparametric Mann-Whitney U test. During the study, it was found that modeled ischemia-reperfusion in rats caused almost complete degeneration of the structure of the pyramidal layer of hippocampal CA1 region, gave uniformity to the structure of the radiant layer, infiltration of microglia, contributed to the disruption of the arrangement of apical dendrite bundles and narrowing of blood vessels as a result of perivascular edema. Also, the modeled pathology reduced the total number of neuronal nuclei in the hippocampal CA1 area, the overwhelming majority of which had signs of pathological changes. Transplantation of mesenchymal stromal cells of various origins, lysate of mesenchymal stromal cells and citicoline contributed to a significant increase in the number of neuronal nuclei in the hippocampal CA1 zone and nuclei that did not undergo pathological changes. The most positive effect was found in the transplantation of mesenchymal stromal cells from human Wharton’s jelly-derived cells. Thus, both in the subacute and recovery periods of ischemic stroke in rats, the transplantation of human Wharton’s jelly-derived mesenchymal stromal cells was significantly surpassed the reference drug citicoline in its ability to reduce the number of pathologically changed nuclei by 1.5 times (p<0.05). At the same time, the number of pathologically unchanged nuclei significantly exceeded the number of nuclei with signs of karyorrhexis and karyopyknosis, so it would be advisable to use mesenchymal stromal cells of various genesis, lysate or citicoline in conditions of acute cerebral ischemia-reperfusion, taking into account their ability to reduce the volume of the infarct. In the future, an injectable drug will be created from the most effective culture of mesenchymal stromal cells in terms of cerebroprotective properties for cell therapy of patients with acute ischemic stroke.

Cotton-YOLO-Seg: An Enhanced YOLOV8 Model for Impurity Rate Detection in Machine-Picked Seed Cotton

The detection of the impurity rate in machine-picked seed cotton is crucial for precision agriculture. This study proposes a novel Cotton-YOLO-Seg cotton-impurity instance segmentation algorithm based on the you only look once version 8 small segmentation model (Yolov8s-Seg). The algorithm achieves precise pixel-level segmentation of cotton and impurities in seed cotton images and establishes a detection model for the impurity rate, enabling accurate detection of the impurity rate in machine-picked cotton. The proposed algorithm removes the Pyramid 4 (P4) feature layer and incorporates Multi-Scale Convolutional Block Attention (MSCBCA) that integrates the Convolutional Block Attention Module (CBAM) and Multi-Scale Convolutional Attention (MSCA) into the Faster Implementation of Cross Stage Partial Bottleneck with 2 Convolutions (C2f) module of the feature extraction network, forming a novel C2f_MSCBCA module. The SlimNeck structure is introduced in the feature fusion network by replacing the P4 feature layer with the small-target detection layer Pyramid 2 (P2). Additionally, transfer learning is employed using the Common Objects in Context (COCO) instance segmentation dataset. The analysis of 100 groups of cotton image samples shows that the Mean Absolute Error (MAE), Root Mean Square Error (RMSE), and Mean Absolute Percentage Error (MAPE) for impurity rate detection are 0.29%, 0.33%, and 3.70%, respectively, which are reduced by 52.46%, 48.44%, and 53.75% compared to the Yolov8s-seg model. The Precision (P), Recall (R), and mean Average Precision at an intersection over union of 0.5 (mAP@0.5) are 85.4%, 78.4%, and 80.8%, respectively, which are improved by 4.2%, 6.2%, and 6.4% compared to Yolov8s-seg model, significantly enhancing the segmentation performance of minor impurities. The Cotton-YOLO-Seg model demonstrates practical significance for precisely detecting the impurity rate in machine-picked seed cotton.

Neuroprotective effects of pink lotus oil in kainic acid-induced epilepsy

Excitotoxicity-induced oxidative stress results in neuronal cell death. Pink lotus essential oil (PLO) is a concentrated volatile oil from lotus blossoms widely used in traditional medicine. This study aimed to explore the possible therapeutic effects of PLO and its underlying mechanisms on kainic acid (KA)-induced oxidative stress and hippocampal cell death in a mouse model of epilepsy. Mice were treated with 100 mg/kg or 200 mg/kg PLO to ameliorate neurodegeneration and seizure-induced behavior induced by KA injection. Pre- and post-treatment of PLO increased antioxidant activities, reduced the seizure score, prevented oxidative stress by increasing GSH and CAT levels, and reduced MDA (malondialdehyde) levels after KA-induced status epilepticus. KA injection created neuronal cell death in the pyramidal layers of CA1 and CA3 subfields of the hippocampus, and affected interneurons in the hilus of the dentate gyrus. PLO treatment notably diminished KA-induced neuronal cell death in these areas through activation of the Akt signaling pathway, increasing reactive astrogliosis, and up-regulation of GDNF expression. Moreover, caspase-3 expression, and microglia activation were significantly decreased in PLO treatments. Taken together, these results suggest that PLO possesses antiepileptic, anti-apoptosic, and neuroprotective effects on KA-induced epileptogenesis indicating that PLO may serve as a dietary supplement option in the treatment of epilepsy or of other neurodegenerative disorders.

An improved YOLOv8 model enhanced with detail and global features for underwater object detection

Underwater object detection is significant for the practical research of mastering existing marine biological resources. In response to the challenges posed by complex underwater environments such as water scattering and variations in object scales, researchers have developed YOLOv8 for object detection, driven by the rising popularity and iteration of deep learning. Building upon this model, we propose an enhanced underwater object detection model named YOLOv8-DGF. Firstly, we replace the convolutional layers of Spatial Pyramid Pooling Fusion (SPPF) with Invertible Neural Networks to further augment the fusion capacity of detailed features, facilitating the preservation of pivotal information while mitigating the impact of noise. Additionally, we introduce a global attention mechanism into Convolution to Fully Connected (C2f), which weights the input features, thereby emphasizing or suppressing feature information from different locations. Through our ‘Detail to Global’ strategy, the model achieved mAP@0.5 scores of 87.7% and 84.8% on the RUOD and URPC2020 datasets, respectively, with improved processing speed. Extensive ablation experiments on the Pascal VOC dataset demonstrate that YOLOv8-DGF outperforms other methods, achieving the best overall performance.

Hierarchical optimization by spatial-temporal indictor in multi-scale decision pyramid for constrained large-scale multi-objective problems

Most existing constrained multi-objective evolutionary algorithms (CMOEAs) are not so efficient when handling constrained large-scale multi-objective problems (CLSMOPs). To overcome CLSMOPs, a hierarchical optimization, based on the spatial–temporal indictor in the decision pyramid (HOSTI-DP), is proposed to determine the dynamic trade-off between feasible and infeasible solutions in the effectively shrunken searching area. The decision pyramid consists of multiple decision spaces with a set of descending numbers of variables; it is initially constructed to speed up the solution convergence by the layer-by-layer dimensionality reduction and increase the population diversity based on the accumulation of these layers. The spatial–temporal indictor considers both the optimization stage (time) and the hierarchy structure of the decision pyramid (space) and it is designed to restrain the prematurely feasible solutions and find the promising infeasible solutions. Finally, the hierarchical optimization strategy, which applies the spatial–temporal indicator to the evolutionary algorithms in every layer of the decision pyramid and dynamically arranging the proportion among them, is designed for comprehensive balance of objectives, constraints, and computational complexity. Nine representative and state-of-the-art CMOEAs have been compared with the HOSTI-DP to demonstrate its effectiveness through comparative experiments on CLSMOPs with equality and inequality constraints and 1000 decision variables. Experimental results show that HOSTI-DP can significantly improve the performance of these CMOEAs.

Hippocampal CA1 Pyramidal Neurons Display Sublayer and Circuitry Dependent Degenerative Expression Profiles in Aged Female Down Syndrome Mice.

Individuals with Down syndrome (DS) have intellectual disability and develop Alzheimer's disease (AD) pathology during midlife, particularly in the hippocampal component of the medial temporal lobe memory circuit. However, molecular and cellular mechanisms underlying selective vulnerability of hippocampal CA1 neurons remains a major knowledge gap during DS/AD onset. This is compounded by evidence showing spatial (e.g., deep versus superficial) localization of pyramidal neurons (PNs) has profound effects on activity and innervation within the CA1 region. We investigated whether there is a spatial profiling difference in CA1 PNs in an aged female DS/AD mouse model. We posit dysfunction may be dependent on spatial localization and innervation patterns within discrete CA1 subfields. Laser capture microdissection was performed on trisomic CA1 PNs in an established mouse model of DS/AD compared to disomic controls, isolating the entire CA1 pyramidal neuron layer and sublayer microisolations of deep and superficial PNs from the distal CA1 (CA1a) region. RNA sequencing and bioinformatic inquiry revealed dysregulation of CA1 PNs based on spatial location and innervation patterns. The entire CA1 region displayed the most differentially expressed genes (DEGs) in trisomic mice reflecting innate DS vulnerability, while trisomic CA1a deep PNs exhibited fewer but more physiologically relevant DEGs, as evidenced by bioinformatic inquiry. CA1a deep neurons displayed numerous DEGs linked to cognitive functions whereas CA1a superficial neurons, with approximately equal numbers of DEGs, were not linked to pathways of dysregulation, suggesting the spatial location of vulnerable CA1 PNs plays an important role in circuit dissolution.

Studying estrogen effects in an in vitro-model of traumatic brain injury (TBI)

In traumatic brain injury (TBI), mechanical forces trigger a series of detrimental processes in the affected brain, which eventually result in substantial neuronal death. TBI has thus become a leading cause of death and disability worldwide. Here we utilized organotypic hippocampal slice cultures from mice to simulate mild diffuse TBI, the most common type, in vitro. We specifically used this model to examine the potential of 17β-estradiol (E2), which is considered to be neuroprotective, to influence injury-induced events, such as astrocyte and microglia activation, and to reduce cell death, if applied acutely after TBI. We found that established consequences of mechanical brain injury are replicated in the model, as increased apoptosis was observed 8 h and PI-uptake was significantly enhanced 24 h after in vitro TBI in CA1 pyramidal layer. GFAP expression was not overall increased, but correlated with cell death, indicating a confined activation of astrocytes associated with cell injury. Similarly, no general increase of microglia was detected, but activated microglia was observed in the vicinity of dying cells. Notably, application of E2 (20 nM) increased GFAP expression after 48 h, but did not significantly reduce cell death at any of the studied time points. We conclude that the presented in vitro TBI model is generally suited to study processes triggered by diffuse mechanical forces acting on brain tissue. Our data further support a stimulating effect of E2 on GFAP expression in astrocytes, but they do not confirm a neuroprotective role of E2 in the early phase of TBI.

Rent‐seeking or value‐creating? The impact of managerial autonomy from state‐built corporate pyramids on M&A performance

AbstractHow to give managers autonomy to improve organisational performance has long been a focus of business practice. In this paper, we use a unique Chinese context to investigate the effect of managerial autonomy arising from state‐built corporate pyramids on mergers and acquisitions (M&A) performance. We find that the number of pyramidal layers between the government and the state‐owned enterprise (SOE) is positively associated with M&A performance. This relationship is stronger when the SOE managers possess professional M&A abilities but weaker when the SOE management team and the government are politically connected. We attribute the positive association to the career path incentives of SOE managers. Additionally, we address the role of managerial autonomy in the M&A process and integration. We also analyse this effect in contexts where managerial autonomy is crucial in some investment decisions. Taken together, our study fills a critical gap on managerial discretion within internal organisational contexts.

A Histological Study of the Effects of Administration and Withdrawal of Anabolic Androgenic Steroid (Nandrolone Decanoate) on the Hippocampus and the Prefrontal Cortex in Adult Male Albino Rats

Abstract Background The PFC and the hippocampus are parts of the limbic systems and have a major role in emotion regulation, memory and learning. Anabolic androgenic steroids (AASs) are large groups of synthetic derivatives of testosterone, prescribed for the treatment of male hypogonadism. Common abuse of AASs has spread among the general population and Aim of the Work The aim of the current work was to study the effects of AASs on the PFC and the hippocampus histologically and statistically and to evaluate the reversibility of these effects in these regions after AASs withdrawal. Material and Methods 24 adult male albino rats (3 – 6) months old (weighing 200-225 gm) were used in the current study and divided into 3 groups; according to the procedure and treatment type: control group (I) (12 rats) and AASs treated group (II) (6 rats) and Withdrawal group (III) (6 rats). Fixation for the brain using bouin solution was done first in situ followed by its removal and transfer to a glass bottle containing bouin solution for 24 hours to ensure complete fixation. The PFC and the hippocampi were obtained through parasagittal section. Specimens were processed for preparation of paraffin blocks then stained with H&E stain and immunohistochemically stained for GFAP antibody. Image analysis &morphometry were performed on stained sections for; number of surviving pyramidal neurons and the mean area percentage of GFAP staining. Results On examination of H&E-stained sections of control groups, the PFC was formed of the six- layers, the molecular layer, outer granular layer, outer pyramidal layer, inner granular layer, inner pyramidal layer and the multiform layer. The Hippocampus was formed of two components: the dentate gyrus (DG), the hippocampus proper (Cornu Ammonis, with its four regions: CA1, CA2, CA3 and CA4). The cells forming the hippocampus proper were arranged in three layers; the molecular, the pyramidal and the polymorphic layers. In immunohistochemically stained section, the present work showed minimal apparent immune-reaction in the cytoplasm and processes of astrocytes in the PFC and CA1 region of the hippocampus in the control group. On examination of H&E-stained sections of the AASs treated groups, signs of neuronal damage were observed. The inner pyramidal layer of the PFC and the pyramidal layer of CA1 region of the hippocampus revealed abnormal shrunken pyramidal cells having deeply stained nuclei, peri-cellular spaces and flame like appearance with pointed end. Moreover, these layers demonstrated also normal pyramidal cells showing also large rounded open vesicular nuclei and prominent nucleoli. Immunohistochemically stained sections of the treated group in both regions showed apparent extensive brownish immunostaining of the astrocytes with ramifying processes along the layer. Examination of H&E-stained sections of the withdrawal group revealed the inner pyramidal layer of the PFC and the pyramidal layer of CA1 region of the hippocampus showing normal pyramidal cells having large rounded open vesicular nuclei, prominent nucleoli and apical dendrites. It also showed dark irregular cells having deeply stained nuclei, peri- cellular spaces and flame like appearance with pointed end. Immunohistochemically stained section of the treated group in both regions showed apparent minimal brownish immunostaining of the astrocytes. Conclusion Results of the present experimental study demonstrated that AASs (in the form of ND) administration affecting the PFC and the hippocampus resulted in several histopathological and morphometric harmful effects which regressed to a lesser extent through its withdrawal after 2 weeks.

Fully Additively 3D Manufactured Conductive Deformable Sensors for Pressure Sensing

Additive manufacturing technologies increasingly revolutionize current production techniques for object manufacturing. Particularly, fused deposition modeling (FDM) strongly impacts production processes by enabling the cost‐effective and efficient creation of structures with complex designs and innovative geometries. The use of conductive filaments in FDM printing is paving the way for the advancement of entirely printed sensors and circuits, although this domain is still in its early stages. In this article, the design and production of bilayer deformable pressure sensors fabricated using conductive thermoplastic polyurethane are investigated. The potential to vary the mechanical and electrical characteristics of FDM‐printed components by adjusting printing parameters is explored. The influence of different levels of material infill (20%, 50%, and 100%) and different contact geometries between layers (domes, pyramids, and cylinders) is studied. Electromechanical tests are carried out to characterize the sensor, applying pressures up to 22 kPa. The 3D‐printed pressure sensors demonstrate tunable mechanical and electrical sensitivities at different infill values, with the highest value of −6.3 kPa−1 achieved by using a pyramid layer at 100% infill. Sensor outputs registered during cyclic tests show reproducible responses with a wide range of sensitivity, paving the way for applicability in recording both static and periodic pressure changes.

Amitriptyline and cholecalciferol amend hippocampal histological structure and myelination during stress in Wistar rats via regulating miR200/BMP4/Olig-2 signaling.

Chronic stress is a universal condition commonly associated with many psychiatric diseases. An extensive body of evidence discussed hippocampal affection upon chronic stress exposure, however, the underlying molecular pathways still need to be identified. We investigated the impact of chronic stress on miR200/BMP/Olig-2 signaling and hippocampal myelination. We also compared the effects of chronic administration of amitriptyline and cholecalciferol on chronically stressed hippocampi. Both amitriptyline and cholecalciferol significantly decreased serum cortisol levels, reduced immobility time in the forced swim test, increased the number of crossed squares in open field test, decreased the hippocampal expression of bone morphogenetic protein 4 (BMP4) and its messenger RNA (mRNA) levels, reduced miR200 expression as compared to untreated chronically stressed rats. Also, both drugs amended the hippocampal neuronal damage, enhanced the surviving cell count, and increased the pyramidal layer thickness of Cornu Ammonis subregion 1 (CA1) and granule cell layer of the dentate gyrus. Cholecalciferol was more effective in increasing the area percentage of myelin basic protein (MBP) and Olig-2 positive cells count in hippocampi of chronic stress-exposed rats than amitriptyline, thus enhancing myelination. We also found a negative correlation between the expression of BMP4, its mRNA, miR200, and the immunoexpression of MBP and Olig-2 proteins. This work underscores the amelioration of the stress-induced behavioral changes, inhibition of miR200/BMP4 signaling, and enhancement of hippocampal myelination following chronic administration of either amitriptyline or cholecalciferol, though cholecalciferol seemed more effective in brain remyelination.

Unusual superconductivity in crystallographically disordered RT2−xSn2 compounds

The discovery of new superconducting materials represents a complementary and crucial tile to shed light on the mechanism controlling the phenomenon of superconductivity. During the search for new superconducting materials, we discovered a new series of intermetallic compounds with the general composition RZn2−xSn2 (R = La, Ce, Pr, Nd). Their formation and crystal structure have been investigated. The Zn content decreases along the series from ≈ 1.50 in LaZn1.50(1)Sn1.98(2) to ≈ 1.32 in NdZn1.321(8)Sn2.01(2), due to the partial occupation of one of the two Zn sites [the Zn1 (2c) site, which from ≈ 50% in the La compound drops to ≈ 42%, ≈ 37% and ≈ 32% in the Ce, Pr and Nd compounds, respectively]. Both the Zn occupation factor and unit cell volume follow the lanthanide contraction. No such compound has been observed with Sm. AC and DC magnetic susceptibility and transport measurements revealed LaZn1.5Sn2 to undergo a sharp superconducting transition at Tc = 5.5 K. In order to search for further possible superconductive homologues, the lanthanum substituted phases La(Zn,T)2–xSn2 (T = Ti, Mn, Fe, Co, Ni, Cu, Pd, Ag, Pt, Au, Cd; x ≈ 0.5) were also prepared. The crystal structure of the ternary compounds is a disordered defective derivative of the tetragonal CaBe2Ge2-type (tP10, P4/nmm), with a partially occupied Zn Wyckoff site and a disordered Sn position. Three related isostructural series, corresponding to three new prototypes, have been identified; they all contain conventional checkered pyramidal layers characteristic of the archetype. The magnetic and transport properties have been measured for some of these substituted quaternary La compounds and we found that superconductivity is preserved in them but in the orthorhombic compounds or when T was a magnetic transition metal (e.g., Ni or Mn). A slight decrease in Tc down to about 4.0 K was detected as a result of the Zn by T atomic substitution.

TRIPS: Trilinear Point Splatting for Real‐Time Radiance Field Rendering

AbstractPoint‐based radiance field rendering has demonstrated impressive results for novel view synthesis, offering a compelling blend of rendering quality and computational efficiency. However, also latest approaches in this domain are not without their shortcomings. 3D Gaussian Splatting [KKLD23] struggles when tasked with rendering highly detailed scenes, due to blurring and cloudy artifacts. On the other hand, ADOP [RFS22] can accommodate crisper images, but the neural reconstruction network decreases performance, it grapples with temporal instability and it is unable to effectively address large gaps in the point cloud. In this paper, we present TRIPS (Trilinear Point Splatting), an approach that combines ideas from both Gaussian Splatting and ADOP. The fundamental concept behind our novel technique involves rasterizing points into a screen‐space image pyramid, with the selection of the pyramid layer determined by the projected point size. This approach allows rendering arbitrarily large points using a single trilinear write. A lightweight neural network is then used to reconstruct a hole‐free image including detail beyond splat resolution. Importantly, our render pipeline is entirely differentiable, allowing for automatic optimization of both point sizes and positions.Our evaluation demonstrate that TRIPS surpasses existing state‐of‐the‐art methods in terms of rendering quality while maintaining a real‐time frame rate of 60 frames per second on readily available hardware. This performance extends to challenging scenarios, such as scenes featuring intricate geometry, expansive landscapes, and auto‐exposed footage. The project page is located at:https://lfranke.github.io/trips

Morphofunctional changes in ventral and dorsal hippocampus in adult rats after chronic mild stress: a preclinical experimental study

Background. Stressful influences, depending on their severity and duration, can cause the development of pathological conditions. Repeated episodes of stress cause functional and structural changes in the central nervous system and can cause the development of depressive conditions. Depression is one of the leading mental illnesses. One of the most stress-sensitive brain structures is the hippocampus. Objective. To study is to evaluate structural changes in the hippocampus, which is considered as a heterogeneous structure with separate dorsal and ventral regions, to evaluate the expression of inducible nitric oxide synthase, endothelial nitric oxide synthase, serine racemase, synaptophysin in a mild stress model.Methods. A study of the effects of mild stress was carried out on 16 adult male Wistar rats (age 12 months, body weight 350–400 g). After acclimatization, the rats were divided into two equal groups (n = 8): intact (control) and stressed. When keeping animals, modeling and removing them from the experiment, we were guided by the Regulations for Carrying Out Work Using Laboratory Animals and the Declaration of Helsinki. Experimental modeling of depression in animals was induced by mild stress exposure for 7 days (30 minutes daily). Euthanasia was performed in a CO2 incubator. The brain was fixed in neutral buffered 10% formalin. Paraffin sections were made in the frontal plane, stained with hematoxylin and eosin, thionin using the Nissl method and examined at a level from –2.40 to –3.96 mm relative to bregma using an Axio Lab A1 microscope (Carl Zeiss Microscopy GmbH, Germany). Photo documentation was carried out with an AxioCam 105 color camera (Carl Zeiss Microscopy GmbH, Germany). Using the Image Analysis module of the ZEN 1.1.2.0 program (Carl Zeiss Microscopy GmbH, Germany) in the pyramidal layer of the hippocampus. Statistical analysis was performed with Microsoft Office Excel 2016 (Microsoft, USA) and Prism 6 (GraphPad Software Inc., USA). Comparisons of two conditions were made by nonparametric Mann-Whitney-U test to avoid a statistical bias of unequal data distribution. The level of significance was set at p < 0.05. The summarized data were presented as a as mean ± standard error of mean.Results. Functional research methods and assessment of pathological changes in hippocampal neurons are presented. An increase in the relative number of wrinkled hyperchromatic pyramidal neurons in the dorsal cornu ammonis field 3 in stressed rats was noted by 23.6% (p < 0.05) compared to the control. There was an increase in the relative number of inducible nitric oxide synthase-immunopositive neurons in the dorsal cornu ammonis field 3 by 40% ( p < 0.05) and the relative area of inducible nitric oxide synthase-immunoreactive material by 35% (p < 0.05) in the pyramidal layer of cornu ammonis field 3 in stressed rats. A decrease in the relative area of synaptophysin-immunopositive material in stressed rats was found in the ventral cornu ammonis field 3 compared to the control group by 16.8% (p < 0.05); decrease in the relative area of serine racemase-immunopositive material in dorsal cornu ammonis field 3 by 4.3% (p < 0.05) and ventral cornu ammonis field 3 by 7.8% (p < 0.05).Conclusion. The results of the study demonstrate that mild stress is an adequate model of depression in rats. In animals exposed to mild stress, pronounced morphological signs of damage to hippocampal neurons were revealed; motor and indicative exploratory activity decreases. Differences were found in morphofunctional changes in the dorsal and ventral parts of the hippocampus under the influence of mild stress. In cornu ammonis field 3 of the dorsal hippocampus, in contrast to the ventral section, more pronounced signs of damage to pyramidal layer neurons were observed. The increase in the relative number of inducible nitric oxide synthase-immunopositive neurons and the relative area of inducible nitric oxide synthase-immunoreactive material in the cornu ammonis field 3 pyramidal layer in stressed rats indicates an increase in nitric oxide production and the participation of nitrooxide-dependent free radical mechanisms of damage to hippocampal neurons. The decrease in the relative area of synaptophysin-immunoreactive material in stressed rats may contribute to changes in synaptic plasticity. A decrease in the relative area of serine racemase-immunoreactive material in the dorsal and ventral parts of cornu ammonis field 3 is considered to be a sign of a possible decrease in N-methyl-D-aspartate-dependent neurotransmission in the hippocampus under stress.