At specific velocities, intense tonal sound can be radiated from the flow around cascaded flat plates. This sound arises from the coupled phenomena of vortex shedding and acoustic resonance. To ...suppress such noise, we actively control the vortex shedding and acoustic radiation by oscillating the edges of every second plate in the cascade. The objective of this investigation was to clarify the effects and mechanism of noise reduction under this control. To understand how the amplitude and frequency of the oscillations influence the controlled flow and acoustic fields around the flat-plate cascade, we conducted direct aeroacoustic simulations using the volume penalization method. The sound pressure level at the resonance frequency was decreased by oscillating the plates at a dimensionless amplitude of 0.15. The pressure reduction failed at oscillation frequencies close to the resonance frequency, because the acoustic resonance occurs at the oscillation frequency. In the audible range of oscillation frequencies (0–20 kHz), the audible overall sound pressure level was not able to be reduced. In contrast, at oscillation frequencies beyond the audible range, both the tonal sound pressure level at the resonance frequency and the audible overall level were decreased. Consequently, the noise radiated from a cascade of plates can be reduced by forced oscillations at a frequency above the audible range. Moreover, we offset the phase of the oscillations between two plates and observed the effect on the acoustic field. At a one-quarter phase offset, the sound pressure level at the oscillation frequency exhibited a vertical asymmetrical directivity.
Chronic opiates induce the development of physical dependence. Opioid physical dependence characterized by withdrawal symptoms, may have very long-lasting effects on the motivation for reward, ...including the incubation of cue-induced drug-seeking behavior. Elucidation of the mechanisms involved in physical dependence is crucial to developing more effective treatment strategies for opioid dependence. Chronic morphine induces production of proinflammatory cytokines in regional-specific sites of the brain. Interleukin-4 (IL-4) is a prototypical anti-inflammatory cytokine that globally suppresses proinflammatory cytokines. Here, we used recombinant herpes simplex virus vector S4IL4 that encode mouse il4 gene to evaluate the therapeutic potential of IL-4 in naloxone-precipitation morphine withdrawal (MW). One week after microinjection of the vector S4IL4 into the PAG LacZ or mouse IL-4 immunoreactivity in the vlPAG was visualized. ELISA assay showed that vector S4IL4 into the PAG induced the expression of IL-4. S4IL4 blunted the morphine withdrawal syndrome. S4IL4 suppressed the upregulated TNFα, NR2B and pC/EBPβ in the PAG induced by MW. These results show that inhibition of proinflammatory factor in the PAG suppressed MW. This study may provide a novel therapeutic approach to morphine physical withdrawal symptoms.
The differences in land resource use methods depend largely on climate change, the natural situation of the area and society. Until now, there has been much research on climate change and the impact ...of economic globalization on land use in the region, but land use hasn't been discussed as a regional strategy. In this research, the land use map was reconstructed while paying attention to the historical changes of Ishigaki Island in Japan. Tourism is the main industry in the island. However, coral reefs, which are important as tourism resources, have been threatened by red soil runoff from farmland and development sites. Red soil runoff became worse in the pineapple boom that has occurred since the 1950s. After that, the "Red soil prevention law of Okinawa Prefecture" was enacted in 1994, and the red soil runoff was suppressed. Based on these social changes, we reconstructed the land use maps in 1921 (before pineapple boom), 1966 (the pineapple boom) and 2004 (after Red Earth Ordinance). As a result, it was found that the cultivated area of pineapple is expanding and reducing with the pineapple boom.
Primary age-related tauopathy (PART) is a form of Alzheimer-type neurofibrillary degeneration occurring in the absence of amyloid-beta (Aβ) plaques. While PART shares some features with Alzheimer ...disease (AD), such as progressive accumulation of neurofibrillary tangle pathology in the medial temporal lobe and other brain regions, it does not progress extensively to neocortical regions. Given this restricted pathoanatomical pattern and variable symptomatology, there is a need to reexamine and improve upon how PART is neuropathologically assessed and staged. We performed a retrospective autopsy study in a collection (n = 174) of post-mortem PART brains and used logistic regression to determine the extent to which a set of clinical and neuropathological features predict cognitive impairment. We compared Braak staging, which focuses on hierarchical neuroanatomical progression of AD tau and Aβ pathology, with quantitative assessments of neurofibrillary burden using computer-derived positive pixel counts on digitized whole slide images of sections stained immunohistochemically with antibodies targeting abnormal hyperphosphorylated tau (p-tau) in the entorhinal region and hippocampus. We also assessed other factors affecting cognition, including aging-related tau astrogliopathy (ARTAG) and atrophy. We found no association between Braak stage and cognitive impairment when controlling for age (p = 0.76). In contrast, p-tau burden was significantly correlated with cognitive impairment even when adjusting for age (p = 0.03). The strongest correlate of cognitive impairment was cerebrovascular disease, a well-known risk factor (p < 0.0001), but other features including ARTAG (p = 0.03) and hippocampal atrophy (p = 0.04) were also associated. In contrast, sex, APOE, psychiatric illness, education, argyrophilic grains, and incidental Lewy bodies were not. These findings support the hypothesis that comorbid pathologies contribute to cognitive impairment in subjects with PART. Quantitative approaches beyond Braak staging are critical for advancing our understanding of the extent to which age-related tauopathy changes impact cognitive function.
Tauopathies are a category of neurodegenerative diseases characterized by the presence of abnormal tau protein-containing neurofibrillary tangles (NFTs). NFTs are universally observed in aging, ...occurring with or without the concomitant accumulation of amyloid-beta peptide (Aβ) in plaques that typifies Alzheimer disease (AD), the most common tauopathy. Primary age-related tauopathy (PART) is an Aβ-independent process that affects the medial temporal lobe in both cognitively normal and impaired subjects. Determinants of symptomology in subjects with PART are poorly understood and require clinicopathologic correlation; however, classical approaches to staging tau pathology have limited quantitative reproducibility. As such, there is a critical need for unbiased methods to quantitatively analyze tau pathology on the histological level. Artificial intelligence (AI)-based convolutional neural networks (CNNs) generate highly accurate and precise computer vision assessments of digitized pathology slides, yielding novel histology metrics at scale. Here, we performed a retrospective autopsy study of a large cohort (n = 706) of human post-mortem brain tissues from normal and cognitively impaired elderly individuals with mild or no Aβ plaques (average age of death of 83.1 yr, range 55-110). We utilized a CNN trained to segment NFTs on hippocampus sections immunohistochemically stained with antisera recognizing abnormal hyperphosphorylated tau (p-tau), which yielded metrics of regional NFT counts, NFT positive pixel density, as well as a novel graph-theory based metric measuring the spatial distribution of NFTs. We found that several AI-derived NFT metrics significantly predicted the presence of cognitive impairment in both the hippocampus proper and entorhinal cortex (p < 0.0001). When controlling for age, AI-derived NFT counts still significantly predicted the presence of cognitive impairment (p = 0.04 in the entorhinal cortex; p = 0.04 overall). In contrast, Braak stage did not predict cognitive impairment in either age-adjusted or unadjusted models. These findings support the hypothesis that NFT burden correlates with cognitive impairment in PART. Furthermore, our analysis strongly suggests that AI-derived metrics of tau pathology provide a powerful tool that can deepen our understanding of the role of neurofibrillary degeneration in cognitive impairment.
The diagnosis of Parkinson's disease (PD) is challenging at all stages due to variable symptomatology, comorbidities, and mimicking conditions. Postmortem assessment remains the gold standard for a ...definitive diagnosis. While it is well recognized that PD manifests pathologically in the central nervous system with aggregation of α-synuclein as Lewy bodies and neurites, similar Lewy-type synucleinopathy (LTS) is additionally found in the peripheral nervous system that may be useful as an antemortem biomarker. We have previously found that detection of LTS in submandibular gland (SMG) biopsies is sensitive and specific for advanced PD; however, the sensitivity is suboptimal especially for early-stage disease. Further, visual microscopic assessment of biopsies by a neuropathologist to identify LTS is impractical for large-scale adoption. Here, we trained and validated a convolutional neural network (CNN) for detection of LTS on 283 digital whole slide images (WSI) from 95 unique SMG biopsies. A total of 8,450 LTS and 35,066 background objects were annotated following an inter-rater reliability study with Fleiss Kappa = 0.72. We used transfer learning to train a CNN model to classify image patches (151 × 151 pixels at 20× magnification) with and without the presence of LTS objects. The trained CNN model showed the following performance on image patches: sensitivity: 0.99, specificity: 0.99, precision: 0.81, accuracy: 0.99, and F-1 score: 0.89. We further tested the trained network on 1230 naïve WSI from the same cohort of research subjects comprising 42 PD patients and 14 controls. Logistic regression models trained on features engineered from the CNN predictions on the WSI resulted in sensitivity: 0.71, specificity: 0.65, precision: 0.86, accuracy: 0.69, and F-1 score: 0.76 in predicting clinical PD status, and 0.64 accuracy in predicting PD stage, outperforming expert neuropathologist LTS density scoring in terms of sensitivity but not specificity. These findings demonstrate the practical utility of a CNN detector in screening for LTS, which can translate into a computational tool to facilitate the antemortem tissue-based diagnosis of PD in clinical settings.
Background:
Addictive drugs lead to reinforcing properties by increasing dopamine in the nucleus accumbens, which is composed of a core and shell regions. Neurons in the nucleus accumbens are divided ...into 2 subtypes based on the differential gene expression of the dopamine D1 receptors and D2 receptors.
Methods:
In the present study, we investigated the role of D2 receptors in the nucleus accumbens core in behaviors and signal transduction induced by psychostimulant methamphetamine in mice that were microinjected with adeno-associated virus vectors containing a microRNA (miRNA) sequence for D2 receptor (adeno-associated virus-miD2r vectors) in the nucleus accumbens core. The adeno-associated virus vectors containing a miRNA sequence for D2 receptor-treated mice (miD2r mice) were assessed at a reduction in D2 receptor, but at no change in dopamine D1 receptor, in the nucleus accumbens core compared with the adeno-associated virus-Mock vectors-treated mice (Mock mice).
Results:
miD2r mice exhibited a reduction in hyperlocomotion that was induced by a single treatment with methamphetamine. The development of locomotor sensitization induced by repeated treatment with methamphetamine exhibited less extension in miD2r mice. In a place conditioning paradigm, the preferred effects of methamphetamine were significantly weaker in miD2r mice than in Mock mice. Furthermore, the single treatment with methamphetamine-induced phosphorylation of extracellular signal regulated kinase and cyclic adenosine monophosphate response element-binding protein in the nucleus accumbens core of miD2r mice was decreased compared with that in Mock mice. Repeated treatment with methamphetamine-induced delta FBJ murine osteosarcoma viral oncogene homolog B accumulation in the nucleus accumbens core of miD2r mice was also attenuated.
Conclusions:
These findings suggest that a D2 receptor-mediated neuronal pathway from the nucleus accumbens core plays an inhibitory role in the development of reinforcing properties.
Abstract The effects on craniofacial growth of two different soft palate repair techniques in two-stage palatoplasty were investigated. This was a retrospective, cross-sectional cohort study of 68 ...children with non-syndromic, complete unilateral cleft lip and palate. Thirty-four patients were treated with the modified Furlow method (F-group) and the remaining 34 with the Widmaier–Perko method (P-group). Craniofacial growth was assessed by analyzing 12 angular and 12 linear measurements on lateral cephalograms. Composite facial diagrams from the two groups were compared with those of a control non-cleft group. Angular and linear measurements did not differ significantly between the two groups, implying that the craniofacial morphology was not affected by the difference in soft palate repair technique. However, small differences in anterior nasal spine and posterior nasal spine were found in cleft patients compared with controls. These findings suggest that the modified Furlow and Widmaier–Perko methods have a similar impact on craniofacial growth. Considering speech function, the modified Furlow method provides better craniofacial growth and speech function. However, the long-term effects of both methods on craniofacial growth after growth cessation remain to be determined.
We present a novel concept for x-ray waveguiding based on electromagnetism in photonic crystals, using a waveguide consisting of a pair of claddings sandwiching a core with a periodic structure. By ...confining the x rays undergoing multiple interference in the core by total reflection, a characteristic waveguide mode whose field distribution matches the periodicity of the core is formed. The distinctively low propagation loss enables the single-mode propagation of x rays. This concept opens broad application possibilities in x-ray physics from coherent imaging to x-ray quantum optics.
The objective of this study was to assess the efficacy of the use of an ex vivo produced oral mucosa equivalent (EVPOME) for intraoral grafting procedures. Autogenous keratinocytes were harvested ...from a punch biopsy 4 weeks prior to surgery, placed in a serum-free culture system and seeded onto a human cadaveric dermal equivalent, AlloDerm®. Thirty patients with either a premalignant or cancerous lesion were triaged into two groups, depending on the stage of disease: Group 1: EVPOME or Group 2: AlloDerm®, control without an epithelial layer. Clinically, EVPOME grafts were easy to handle and showed excellent compliance on grafting. Both, EVPOME and AlloDerm® grafts, showed a 100% take rate. At 6 days post-grafting, the EVPOME clinically showed changes indicating vascular ingrowth and had cytologic evidence of the persistence of grafted cultured keratinocytes on the surface. The EVPOME grafts had enhanced maturation of the underlying submucosal layer associated with rapid epithelial coverage when compared to the AlloDerm® grafts at biopsies taken at 28 days post-grafting. In summary, EVPOME appears to be an acceptable oral mucosal substitute for human intraoral grafting procedures and results in a more favorable wound healing response than AlloDerm® alone.
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