Semi-supervised learning, i.e. jointly learning from labeled and unlabeled samples, is an active research topic due to its key role on relaxing human supervision. In the context of image classification, recent advances to learn from unlabeled samples are mainly focused on consistency regularization methods that encourage invariant predictions for different perturbations of unlabeled samples. We, conversely, propose to learn from unlabeled data by generating soft pseudo-labels using the network predictions. We show that a naive pseudo-labeling overfits to incorrect pseudo-labels due to the so-called confirmation bias and demonstrate that mixup augmentation and setting a minimum number of labeled samples per mini-batch are effective regularization techniques for reducing it. The proposed approach achieves state-of-the-art results in CIFAR-10/100, SVHN, and Mini-ImageNet despite being much simpler than other methods. These results demonstrate that pseudo-labeling alone can outperform consistency regularization methods, while the opposite was supposed in previous work. Source code is available at https://git.io/fjQsC.
The ventral midbrain (vMb) is organized into distinct anatomical domains and contains cohorts of functionally distinct subtypes of midbrain dopamine (mDA) neurons. We tested the hypothesis that genetic history and timing of gene expression within mDA neuron progenitors impart spatial diversity. Using Genetic Inducible Fate Mapping to mark the Sonic hedgehog (Shh) and Gli1 lineages at varying embryonic stages, we performed a quantitative and qualitative comparison of the two lineages’ contribution to the mDA neuron domains. Dynamic changes in Shh and Gli1 expression in the vMb primordia delineated their spatial contribution to the E12.5 vMb: Both lineages first contributed to the medial domain, but subsequently the Gli1 lineage exclusively contributed to the lateral vMb while the Shh lineage expanded more broadly across the vMb. The contribution of both lineages to the differentiated mDA neuron domain was initially biased anteriorly and became more uniform across the anterior/posterior vMb throughout development. Our findings demonstrate that the early Shh and Gli1 lineages specify mDA neurons of the substantia nigra pars compacta while the late Shh and Gli1 lineages maintain their progenitor state longer in the posterior vMb to extend the production of mDA neurons in the ventral tegmental area. Together, our study demonstrates that the timing of gene expression along with the genetic lineage (Shh or Gli1) within the neural progenitors segregate mDA neurons into distinct spatial domains.
Vitamin D research is discussed in light of the hypothesis that the lower average levels of vitamin D frequently observed in autoimmune disease are not a sign of deficiency. Instead, it is proposed that the lower levels result from chronic infection with intracellular bacteria that dysregulate vitamin D metabolism by causing vitamin D receptor (VDR) dysfunction within phagocytes. The VDR dysfunction causes a decline in innate immune function that causes susceptibility to additional infections that contribute to disease progression. Evidence has been accumulating that indicates that a number of autoimmune diseases can be reversed by gradually restoring VDR function with the VDR agonist olmesartan and subinhibitory dosages of certain bacteriostatic antibiotics. Diseases showing favorable responses to treatment so far include systemic lupus erythematosis, rheumatoid arthritis, scleroderma, sarcoidosis, Sjogren's syndrome, autoimmune thyroid disease, psoriasis, ankylosing spondylitis, Reiter's syndrome, type I and II diabetes mellitus, and uveitis. Disease reversal using this approach requires limitation of vitamin D in order to avoid contributing to dysfunction of nuclear receptors and subsequent negative consequences for immune and endocrine function. Immunopathological reactions accompanying bacterial cell death require a gradual elimination of pathogens over several years. Practical and theoretical implications are discussed, along with the compatibility of this model with current research.
The catastrophic failure of human metabolism observed in autoimmune disease results from a common underlying pathogenesis - the successive accumulation of pathogens into the microbiome over time, and the ability of such pathogens to dysregulate gene transcription, translation, and human metabolic processes. Autoimmune diseases are more likely passed in families because of the inheritance of a familial microbiome, rather than Mendelian inheritance of genetic abnormalities. We can stimulate innate immune defenses and allow patients to target pathogens, but cell death results in immunopathology.
The structure and innervation as determined by methylene blue techniques of the sensilla of the maxillary palp, galea, mandible, labrum, and labial palp of the spruce budworm larva are described, based on light and scanning electron microscopy. An attempt is made to identify the function of various sensilla by comparing them with those of other insects. The function of the gustatory sensilla on the galea and epipharynx is confirmed electrophysiologically.
A white spruce, Picea glauca (Moench) Voss (Pinaceae), plantation in southern Quebec was found to contain two distinct types of trees, the first resistant and the second susceptible to attack by spruce budworm, Choristoneura fumiferana (Clemens) (Lepidoptera: Tortricidae). To identify the mechanisms of white spruce resistance to spruce budworm, we studied the role of epicuticular waxes, comparing (i) the foliar chemistry of susceptible and resistant trees and (ii) the feeding pattern of larvae at first contact with the foliage. Needles collected from resistant trees contained concentrations of the monoterpenes α-pinene and myrcene that were 307% and 476%, respectively, above those found in needles collected from susceptible trees. Although there were no significant differences in probing behaviour, significantly fewer larvae transitioned from probing to feeding on resistant needles; this led to fewer feeding bouts as well as a significantly shorter first meal. Removal of waxes increased the number of individuals transitioning from probing to feeding on resistant needles; this led to more feeding bouts. Our results demonstrate that monoterpenes influence the pattern of feeding of spruce budworm larvae as well as playing an important role in white spruce resistance.
Recent research has implicated vitamin D deficiency (serum levels of 25-hydroxyvitamin D <50 nmol/L) with a number of chronic conditions, including autoimmune conditions such as multiple sclerosis, lupus, and psoriasis, and chronic conditions such as osteoporosis, osteoarthritis, metabolic syndrome, fibromyalgia and chronic fatigue syndrome. It has been assumed that low levels of 25-hydroxyvitamin D (25-D) accurately indicate vitamin D storage and vitamin D receptor (VDR)-mediated control of calcium metabolism and innate immunity. To evaluate this assumption, 25-D and 1,25-dihydroxyvitamin D3 (1,25-D) levels were measured in 100 Canadian patients with these conditions. Additionally, other inflammatory markers (CK, CRP) were measured. Results showed a strong positive association between these autoimmune conditions and levels of 1,25-D >110 pmol/L. However, there was little association with vitamin D deficiency or the other inflammatory markers, meaning that the results challenge the assumption that serum levels of 25-D are a sensitive measure of the autoimmune disease state. Rather, these findings support the use of 1,25-D as a clinical marker in autoimmune conditions. High levels of 1,25-D may result when dysregulation of the VDR by bacterial ligands prevents the receptor from expressing enzymes necessary to keep 1,25-D in a normal range.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.