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NeuroImage Jun 2024Brain disorders are often associated with changes in brain structure and function, where functional changes may be due to underlying structural variations. Gray matter...
Brain disorders are often associated with changes in brain structure and function, where functional changes may be due to underlying structural variations. Gray matter (GM) volume segmentation from 3D structural MRI offers vital structural information for brain disorders like schizophrenia, as it encompasses essential brain tissues such as neuronal cell bodies, dendrites, and synapses, which are crucial for neural signal processing and transmission; changes in GM volume can thus indicate alterations in these tissues, reflecting underlying pathological conditions. In addition, the use of the ICA algorithm to transform high-dimensional fMRI data into functional network connectivity (FNC) matrices serves as an effective carrier of functional information. In our study, we introduce a new generative deep learning architecture, the conditional efficient vision transformer generative adversarial network (cEViT-GAN), which adeptly generates FNC matrices conditioned on GM to facilitate the exploration of potential connections between brain structure and function. We developed a new, lightweight self-attention mechanism for our ViT-based generator, enhancing the generation of refined attention maps critical for identifying structural biomarkers based on GM. Our approach not only generates high quality FNC matrices with a Pearson correlation of 0.74 compared to real FNC data, but also uses attention map technology to identify potential biomarkers in GM structure that could lead to functional abnormalities in schizophrenia patients. Visualization experiments within our study have highlighted these structural biomarkers, including the medial prefrontal cortex (mPFC), dorsolateral prefrontal cortex (DL-PFC), and cerebellum. In addition, through cross-domain analysis comparing generated and real FNC matrices, we have identified functional connections with the highest correlations to structural information, further validating the structure-function connections. This comprehensive analysis helps to understand the intricate relationship between brain structure and its functional manifestations, providing a more refined insight into the neurobiological research of schizophrenia.
PubMed: 38851549
DOI: 10.1016/j.neuroimage.2024.120674 -
Frontiers in Physiology 2024Ants are capable of learning long visually guided foraging routes with limited neural resources. The visual scene memory needed for this behaviour is mediated by the...
Ants are capable of learning long visually guided foraging routes with limited neural resources. The visual scene memory needed for this behaviour is mediated by the mushroom bodies; an insect brain region important for learning and memory. In a visual navigation context, the mushroom bodies are theorised to act as familiarity detectors, guiding ants to views that are similar to those previously learned when first travelling along a foraging route. Evidence from behavioural experiments, computational studies and brain lesions all support this idea. Here we further investigate the role of mushroom bodies in visual navigation with a spiking neural network model learning complex natural scenes. By implementing these networks in GeNN-a library for building GPU accelerated spiking neural networks-we were able to test these models offline on an image database representing navigation through a complex outdoor natural environment, and also online embodied on a robot. The mushroom body model successfully learnt a large series of visual scenes (400 scenes corresponding to a 27 m route) and used these memories to choose accurate heading directions during route recapitulation in both complex environments. Through analysing our model's Kenyon cell (KC) activity, we were able to demonstrate that KC activity is directly related to the respective novelty of input images. Through conducting a parameter search we found that there is a non-linear dependence between optimal KC to visual projection neuron (VPN) connection sparsity and the length of time the model is presented with an image stimulus. The parameter search also showed training the model on lower proportions of a route generally produced better accuracy when testing on the entire route. We embodied the mushroom body model and comparator visual navigation algorithms on a Quanser Q-car robot with all processing running on an Nvidia Jetson TX2. On a 6.5 m route, the mushroom body model had a mean distance to training route (error) of 0.144 ± 0.088 m over 5 trials, which was performance comparable to standard visual-only navigation algorithms. Thus, we have demonstrated that a biologically plausible model of the ant mushroom body can navigate complex environments both in simulation and the real world. Understanding the neural basis of this behaviour will provide insight into how neural circuits are tuned to rapidly learn behaviourally relevant information from complex environments and provide inspiration for creating bio-mimetic computer/robotic systems that can learn rapidly with low energy requirements.
PubMed: 38841209
DOI: 10.3389/fphys.2024.1379977 -
Journal of Hazardous Materials Aug 2024The ceramic industry is a production sector that can efficiently recycle its own processing residues, achieving a reuse index of almost 100%. Recently, the range of...
The ceramic industry is a production sector that can efficiently recycle its own processing residues, achieving a reuse index of almost 100%. Recently, the range of waste from other industrial sectors that can be used as secondary raw materials in ceramic bodies has expanded. However, such an expansion potentially introduces hazardous components. This study aimed to quantitatively assess the efficiency of inertising hazardous elements (HEs) through ceramisation. The ceramics were characterised through XRPD, SEM-EDS and leaching tests to determine their leaching behaviour and the mechanisms of element immobilisation in neoformation phases during the ceramisation process. The results indicate high immobilisation efficiency for Ba, Co, Cr, Cu, Pb, Sb, Sn and Zn. However, Mo is the main element of concern owing to its poor retention in ceramic bodies. This is likely due to the formation of oxyanionic complexes that are difficult to immobilise in silicate matrices. In addition, the ceramic bodies exhibit substantial differences that appear to be associated with variations in pseudo-structural components and the degree of polymerisation of their vitreous phase.
PubMed: 38838526
DOI: 10.1016/j.jhazmat.2024.134657 -
Proceedings of the National Academy of... Jun 2024Human pose, defined as the spatial relationships between body parts, carries instrumental information supporting the understanding of motion and action of a person. A...
Human pose, defined as the spatial relationships between body parts, carries instrumental information supporting the understanding of motion and action of a person. A substantial body of previous work has identified cortical areas responsive to images of bodies and different body parts. However, the neural basis underlying the visual perception of body part relationships has received less attention. To broaden our understanding of body perception, we analyzed high-resolution fMRI responses to a wide range of poses from over 4,000 complex natural scenes. Using ground-truth annotations and an application of three-dimensional (3D) pose reconstruction algorithms, we compared similarity patterns of cortical activity with similarity patterns built from human pose models with different levels of depth availability and viewpoint dependency. Targeting the challenge of explaining variance in complex natural image responses with interpretable models, we achieved statistically significant correlations between pose models and cortical activity patterns (though performance levels are substantially lower than the noise ceiling). We found that the 3D view-independent pose model, compared with two-dimensional models, better captures the activation from distinct cortical areas, including the right posterior superior temporal sulcus (pSTS). These areas, together with other pose-selective regions in the LOTC, form a broader, distributed cortical network with greater view-tolerance in more anterior patches. We interpret these findings in light of the computational complexity of natural body images, the wide range of visual tasks supported by pose structures, and possible shared principles for view-invariant processing between articulated objects and ordinary, rigid objects.
Topics: Humans; Magnetic Resonance Imaging; Male; Female; Adult; Brain; Brain Mapping; Visual Perception; Posture; Young Adult; Imaging, Three-Dimensional; Photic Stimulation; Algorithms
PubMed: 38830105
DOI: 10.1073/pnas.2317707121 -
Frontiers in Psychiatry 2024Body image dissatisfaction has emerged as an important determinant of dietary and physical activity, which in turn determine adolescents' nutritional status. Hence, it...
PURPOSE
Body image dissatisfaction has emerged as an important determinant of dietary and physical activity, which in turn determine adolescents' nutritional status. Hence, it is important to understand predictors of body image dissatisfaction. Therefore, this study aimed to assess body image dissatisfaction and its associated factors among secondary school adolescents in the study area.
METHODS
Data collected for other purposes were used to assess body image dissatisfaction among adolescents in Harar town. Body image dissatisfaction was assessed using the Body Part Satisfaction Scale. Data processing and analysis were performed using STATA version 14, and binary logistic regression was used to identify factors associated with body image dissatisfaction. Factors associated with body image dissatisfaction were determined by estimating AOR along with 95% CI and the statistical significance was declared at a p-value less than or equal to 0.05.
RESULT
The prevalence of body image dissatisfaction was 22.06% [95% CI (19.63, 24.70)]. This study also revealed that males were more dissatisfied with their upper torso and face, and females were more dissatisfied with their middle torso, lower torso, height, and weight than males. In this study, body image dissatisfaction was associated with perception of being fat [AOR = 1.89, 95% CI (1.23, 2.91)], anxiety [AOR = 1.59, 95% CI (1.02, 2.48)], and cigarette smoking [AOR = 1.63, 95% CI (1.03, 2.58)].
CONCLUSION
Almost one in five secondary school adolescents in Harar had body image dissatisfaction, which was significantly associated with perceptions of being fat, anxiety, and smoking. In this study, a significant number of the adolescents experienced body image dissatisfaction. Hence, all concerned bodies have to take action to reduce the burden.
PubMed: 38827436
DOI: 10.3389/fpsyt.2024.1397155 -
Frontiers in Cellular Neuroscience 2024Multiple sclerosis (MS) is an inflammatory and demyelinating disease of the central nervous system (CNS). Current therapies primarily target the inflammatory component...
INTRODUCTION
Multiple sclerosis (MS) is an inflammatory and demyelinating disease of the central nervous system (CNS). Current therapies primarily target the inflammatory component of the disease and are highly effective in early stages of MS while limited therapies have an effect in the more chronic progressive stages of MS where resident glia have a larger role. MS lesions tend to be inflammatory even after the initial peripheral immune cell invasion has subsided and this inflammation is known to cause alternative splicing events.
METHODS
We used qPCR of normal-appearing white matter and white matter lesions from postmortem MS tissue, studies, and immunostaining in MS tissue to investigate the alternative splicing of one gene known to be important during recovery in an animal model of MS, .
RESULTS
We found a novel, intron-retained isoform which has not been annotated, upregulated specifically in MS patient white matter lesions. We found that this novel isoform activates the nonsense-mediated decay pathway in primary human astrocytes, the most populous glial cell in the CNS, and is then degraded. Overexpression of this isoform in astrocytes leads to an increased number of processing bodies , the primary site of mRNA decay. Finally, we demonstrated that MS white matter lesions have a higher burden of processing bodies compared to normal-appearing white matter, predominantly in GFAP-positive astrocytes.
DISCUSSION
The increase in alternative splicing of the gene, the stress that this alternative splicing causes, and the observation that processing bodies are increased in white matter lesions suggests that the lesion microenvironment may lead to increased alternative splicing of many genes. This alternative splicing may blunt the protective or reparative responses of resident glia in and around white matter lesions in MS patients.
PubMed: 38812791
DOI: 10.3389/fncel.2024.1379261 -
The Journal of Biological Chemistry May 2024Ataxin-2 (Atx2) is a polyglutamine (polyQ) tract-containing RNA-binding protein, while its polyQ expansion may cause protein aggregation that is implicated in the...
Ataxin-2 (Atx2) is a polyglutamine (polyQ) tract-containing RNA-binding protein, while its polyQ expansion may cause protein aggregation that is implicated in the pathogenesis of neurodegenerative diseases such as spinocerebellar ataxia type 2 (SCA2). However, the molecular mechanism underlying how Atx2 aggregation contributes to the proteinopathies remains elusive. Here, we investigated the influence of Atx2 aggregation on the assembly and functionality of cellular processing bodies (P-bodies) by using biochemical and fluorescence imaging approaches. We have revealed that polyQ-expanded (PQE) Atx2 sequesters the DEAD-box RNA helicase (DDX6), an essential component of P-bodies, into aggregates or puncta via some RNA sequences. The N-terminal like-Sm (LSm) domain of Atx2 (residues 82-184) and the C-terminal helicase domain of DDX6 are responsible for the interaction and specific sequestration. Moreover, sequestration of DDX6 may aggravate pre-mRNA mis-splicing, and interfere with the assembly of cellular P-bodies, releasing the endoribonuclease MARF1 that promotes mRNA decay and translational repression. Rescuing the DDX6 protein level can recover the assembly and functionality of P-bodies, preventing targeted mRNA from degradation. This study provides a line of evidence for sequestration of the P-body components and impairment of the P-body homeostasis in dysregulating RNA metabolism, which is implicated in the disease pathologies and a potential therapeutic target.
PubMed: 38810698
DOI: 10.1016/j.jbc.2024.107413 -
Current Biology : CB Jun 2024The mitochondrial proteome is comprised of approximately 1,100 proteins, all but 12 of which are encoded by the nuclear genome in C. elegans. The expression of...
The mitochondrial proteome is comprised of approximately 1,100 proteins, all but 12 of which are encoded by the nuclear genome in C. elegans. The expression of nuclear-encoded mitochondrial proteins varies widely across cell lineages and metabolic states, but the factors that specify these programs are not known. Here, we identify mutations in two nuclear-localized mRNA processing proteins, CMTR1/CMTR-1 and SRRT/ARS2/SRRT-1, which we show act via the same mechanism to rescue the mitochondrial complex I mutant NDUFS2/gas-1(fc21). CMTR-1 is an FtsJ-family RNA methyltransferase that, in mammals, 2'-O-methylates the first nucleotide 3' to the mRNA CAP to promote RNA stability and translation. The mutations isolated in cmtr-1 are dominant and lie exclusively in the regulatory G-patch domain. SRRT-1 is an RNA binding partner of the nuclear cap-binding complex and determines mRNA transcript fate. We show that cmtr-1 and srrt-1 mutations activate embryonic expression of NDUFS2/nduf-2.2, a paralog of NDUFS2/gas-1 normally expressed only in dopaminergic neurons, and that nduf-2.2 is necessary for the complex I rescue by the cmtr-1 G-patch mutant. Additionally, we find that loss of the cmtr-1 G-patch domain cause ectopic localization of CMTR-1 protein to processing bodies (P bodies), phase-separated organelles involved in mRNA storage and decay. P-body localization of the G-patch mutant CMTR-1 contributes to the rescue of the hyperoxia sensitivity of the NDUFS2/gas-1 mutant. This study suggests that mRNA methylation at P bodies may control nduf-2.2 gene expression, with broader implications for how the mitochondrial proteome is translationally remodeled in the face of tissue-specific metabolic requirements and stress.
Topics: Animals; Caenorhabditis elegans; Caenorhabditis elegans Proteins; Electron Transport Complex I; Dopaminergic Neurons; Mutation; Methyltransferases; Mitochondria; Mitochondrial Proteins; NADH Dehydrogenase
PubMed: 38810637
DOI: 10.1016/j.cub.2024.04.079 -
PloS One 2024In the realm of industrial inspection, the precise assessment of internal thread quality is crucial for ensuring mechanical integrity and safety. However, challenges...
In the realm of industrial inspection, the precise assessment of internal thread quality is crucial for ensuring mechanical integrity and safety. However, challenges such as limited internal space, inadequate lighting, and complex geometry significantly hinder high-precision inspection. In this study, we propose an innovative automated internal thread detection scheme based on machine vision, aimed at addressing the time-consuming and inefficient issues of traditional manual inspection methods. Compared with other existing technologies, this research significantly improves the speed of internal thread image acquisition through the optimization of lighting and image capturing devices. To effectively tackle the challenge of image stitching for complex thread textures, an internal thread image stitching technique based on a cylindrical model is proposed, generating a full-view thread image. The use of the YOLOv8 model for precise defect localization in threads enhances the accuracy and efficiency of detection. This system provides an efficient and intuitive artificial intelligence solution for detecting surface defects on geometric bodies in confined spaces.
Topics: Image Processing, Computer-Assisted; Algorithms; Artificial Intelligence
PubMed: 38805511
DOI: 10.1371/journal.pone.0304224 -
Cortico-amygdala synaptic structural abnormalities produced by templated aggregation of α-synuclein.BioRxiv : the Preprint Server For... May 2024Parkinson's disease (PD) and Dementia with Lewy bodies (DLB) are characterized by neuronal α-synuclein (α-syn) inclusions termed Lewy Pathology, which are abundant in...
Parkinson's disease (PD) and Dementia with Lewy bodies (DLB) are characterized by neuronal α-synuclein (α-syn) inclusions termed Lewy Pathology, which are abundant in the amygdala. The basolateral amygdala (BLA), in particular, receives projections from the thalamus and cortex. These projections play a role in cognition and emotional processing, behaviors which are impaired in α-synucleinopathies. To understand if and how pathologic α-syn impacts the BLA requires animal models of α-syn aggregation. Injection of α-synuclein pre-formed fibrils (PFFs) into the striatum induces robust α-synuclein aggregation in excitatory neurons in the BLA that corresponds with reduced contextual fear conditioning. At early time points after aggregate formation, cortico-amygdala excitatory transmission is abolished. The goal of this project was to determine if α-syn inclusions in the BLA induce synaptic degeneration and/or morphological changes. In this study, we used C57BL/6J mice injected bilaterally with PFFs in the dorsal striatum to induce α-syn aggregate formation in the BLA. A method was developed using immunofluorescence and three-dimensional reconstruction to analyze excitatory cortico-amygdala and thalamo-amygdala presynaptic terminals closely juxtaposed to postsynaptic densities. The abundance and morphology of synapses were analyzed at 6- or 12-weeks post-injection of PFFs. α-Syn aggregate formation in the BLA did not cause a significant loss of synapses, but cortico-amygdala and thalamo-amygdala presynaptic terminals and postsynaptic densities with aggregates of α-synuclein show increased volumes, similar to previous findings in human DLB cortex, and in non-human primate models of PD. Transmission electron microscopy showed that PFF-injected mice showed reduced intervesicular distances similar to a recent study showing phospho-serine-129 α-synuclein increases synaptic vesicle clustering. Thus, pathologic α-synuclein causes major alterations to synaptic architecture in the BLA, potentially contributing to behavioral impairment and amygdala dysfunction observed in synucleinopathies.
PubMed: 38798467
DOI: 10.1101/2024.05.15.594419