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Effects of size and atomic defects on the buckling of single-layer and double-layer graphene nanoplates using AFEM
Electrophysiological Brain Connectivity and Subjective States Evoked by Electrical Stimulation of the Human Mid-thalamus
Recent developments in intracranial EEG allow direct recordings from the human thalamus, offering new insight into thalamocortical relationships in the human brain. In this study, we applied direct intracranial electrical stimulation (iES) to the mid-thalamus, within or close to the mediodorsal nucleus, to examine its impact on conscious experience and causal brain connectivity in 30 patients with focal epilepsy (10 females, 128 sites; 4 ± 1 sites per patient). Applying 50 Hz stimulations (iES HF ) in the mid-thalamus region elicited changes in conscious experience in 11 of 12 patients (39 sites; 83 stimulations across 27 unique pairs), predominantly in the visceral, emotional, or somatosensory domains and often described as unpleasant without any seemingly obvious lateralization effect. Our connectivity analyses based on single-pulse 0.5 Hz stimulations (iES LF ), at the individual brain level, revealed strong electrophysiological connectivity between the mid-thalamus and the insula, anterior and midcingulate, and the other prefrontal cortices and medial temporal lobe structures. Notably, inflow signals from some of the sites to the mid-thalamus were significantly stronger than those in the reverse direction, indicating clear asymmetry in connectivity. These findings demonstrate that stimulation of the human thalamus modulates conscious experience and reveal an asymmetric electrophysiological relationship between the thalamus and human cerebral cortex.
The transcription factor AP-1 regulates the catalase family and oxidative stress adaptation in the dermatophyte Trichophyton rubrum
Physical exercise and school adaptation among junior high school students: the chain mediating roles of self-efficacy and mental health
Bright Light Shapes Diurnal Sleep–Wake Rhythms with Associated c-Fos Activity in the Anterior Paraventricular Thalamus in the Nile Grass Rat
Sleep profiles of the Nile grass rat, a day-active rodent that is widely used in research, have not been fully characterized. Sleep electroencephalograms were therefore recorded in male Nile grass rats maintained under 12 h light/dark (LD) cycles with different light intensities and spectra. A crepuscular elevation in wakefulness was observed under LD cycles of 150 lux white light. Moreover, a stepwise increase in daytime wakefulness and a reduction in daytime non-rapid eye movement sleep were observed at higher light intensities (300 or 1,000 lux). The amount of nighttime non-rapid eye movement sleep remained stable regardless of preceding light conditions, whereas delta electroencephalogram power was enhanced during the day and early nighttime under 1,000 lux LD cycles, suggesting homeostatic control of sleep quality. Although Nile grass rats have ultraviolet-sensitive photoreceptors, daytime coexposures of ultraviolet light did not affect daily sleep amounts or quality under 300 lux LD cycles. We then explored correlations between brain activity and sleep–wake levels or light intensities (150 or 1,000 lux) using c-Fos immunostaining in brains sampled at four different times of the day. c-Fos immunoreactivity in the hypothalamic suprachiasmatic nucleus—the central circadian clock—displayed the highest signal at light onset under 1,000 lux LD cycles. Furthermore, c-Fos immunoreactivity in the anterior paraventricular thalamic nucleus increased at dawn and dusk, and the midday signal was amplified by 1,000 lux light. These results elucidate light-dependent sleep–wake profiles in Nile grass rats and suggest the possible involvement of the anterior paraventricular thalamic nucleus in daytime arousal control.
Prevalence of sarcopenia and population attributable fraction of related factors in Iranian older adults from the IMOS‑2021 study
Exaggerated NMDA Receptor-Primed Metaplasticity via SK Channel Dysregulation in <i>Fmr1</i> Knockout Mice
Fragile X syndrome (FXS), the most common monogenic neurodevelopmental disorder associated with autism and intellectual disability, results from the loss of expression of the X-linked FMR1 gene. Synaptic and circuit-level abnormalities in the brain are well documented in FXS and extensively studied in the Fmr1 KO mouse model. In CA1 hippocampal neurons, functional, molecular, and structural synaptic changes have been described, yet the canonical form of Hebbian CA1 long-term potentiation (LTP) remains intact in Fmr1 KO mice. Here we examined whether state-dependent synaptic plasticity in CA1, in which prior “priming” activity modulates subsequent synaptic plasticity, was altered in male Fmr1 KO mice. We found that NMDA receptor activation prior to LTP induction produced metaplastic inhibition of LTP, which was exaggerated in Fmr1 KO mice. This effect was mediated by the activity of small conductance calcium-activated potassium (SK) channels which was enhanced after NMDA priming and dampened dendritic excitability. Blocking SK channels during NMDA-primed LTP induction eliminated the abnormal metaplasticity in Fmr1 KO slices, implicating altered SK activity in the exaggerated LTP inhibition in Fmr1 KO mice. These finding reveal a disrupted functional coupling between NMDA receptors and SK channels in Fmr1 KO mice, altering the impact of priming on LTP expression in the CA1. Altered metaplasticity may represent a neural correlate of impaired hippocampal function in Fmr1 KO mice and potentially contribute to clinical manifestations in FXS individuals.
Comparing implicit boundary and hierarchical plurigaussian simulation for modeling geological domains using hard and soft data
Abstract The delineation of geological domains is a crucial step in mineral resource evaluation, as it directly influences the accuracy of grade models. Instead of a single geological interpretation, geostatistical simulation generates multiple scenarios that reproduce the spatial variability and can be used to assess uncertainty in the spatial layout of the geological domains. This study compares two established geostatistical simulation frameworks–Implicit Boundary Simulation (IBS) and Hierarchical Plurigaussian Simulation (HPGS)–and proposes practical, rigorous pathways to incorporate interpreted geological models as soft data. In IBS, the interpreted model enters as an auxiliary signed–distance covariate which is co-simulated with the down-the-hole signed distance derived from sampling data. In HPGS, the interpreted model informs local domain proportions through a moving window that controls local truncation thresholds. Both methods were applied to a porphyry copper deposit in northern Chile for modeling five mineralization zones under pronounced data scarcity. One hundred conditional realizations were generated for each approach and probability maps, most-probable domain maps, and match–mismatch tables against the interpreted model and drilling data were computed. The results demonstrated that, while both approaches benefited from incorporating soft data, HPGS yielded results that are more consistent with the interpreted model, particularly for mineralization zones exhibiting small-scale variability.
Modulating effect of salivary pellicle conditioning of titanium surfaces on the development of biofilms of Pseudomonas aeruginosa and Staphylococcus species
Abstract To evaluate the modulating effect of salivary pellicle (SP) on titanium (Ti) surfaces on the development of Staphylococcus species and Pseudomonas aeruginosa biofilm. Ti substrates were incubated for 2 h with whole saliva samples to induce the salivary pellicle formation. After conditioning with SP, Ti substrates were incubated for 12 h with P. aeruginosa , S. aureus , S. epidermidis strains individually, in addition to co-culture of the three bacteria. The biofilm development on the Ti substrates was visualized by Scanning Electron Microscopy (SEM). To measure the metabolic activity and vitality of cells within the biofilm the XTT assay was used, while the proportion of the species tested in the biofilms was determined throughout DNA-DNA hybridizations. SP modulated the biofilm development on the Ti surfaces, favoring the formation of P. aeruginosa biofilms, while inhibiting the growth of S. aureus and S. epidermidis . In the case of the coculture biofilms, a predominance of P. aeruginosa cells over the Staphylococcus strains was observed. When the bacterial strains were tested individually, the SP importantly reduced the development of biofilms of Staphylococcus species, whereas it favored the development of P. aeruginosa biofilms on Ti surfaces. Similarly, when mixed biofilms developed, SP favored the selective expansion of P. aeruginosa and S. aureus growth over S. epidermidis growth. The results of this study provide valuable information on the modulatory effect of the SP on the development of opportunistic bacteria biofilms on Ti surfaces used for dental and oral implantology.
Extracellular HSPA5/Grp78/BiP, Acting through Its Receptor Plexin-B3 and Nkx2.8, Regulates Oligodendrocyte Myelination in Mice
Myelin sheaths are generated from differentiated plasma membranes of oligodendroglial cells (oligodendrocytes) during development. Despite detailed functional studies, such as aiding nerve conduction velocity, it remains unclear which extracellular signals from neurons interact with oligodendrocytes to control oligodendrocyte development and how these are achieved. Herein, we demonstrate that the Plexin molecule Plexin-B3, generally known as a receptor for Sema family signaling proteins, is specifically expressed in oligodendrocytes and plays a key role in promoting oligodendrocyte maturation and myelination. Oligodendrocyte-specific conditional male knock-out mice of Plexin-B3 exhibited decreased myelin thickness and myelin marker protein expression, compared with littermate controls. Unexpectedly, we identified heat shock protein family A member 5 (HSPA5)/Grp78/BiP as the neuron-secreted ligand of Plexin-B3. Indeed, neuron-specific knockdown of HSPA5 in male mice revealed a critical role for myelin thickness not only at the biochemical level but also at the histochemical one. Furthermore, the transcription factor Nkx2.8, which plays a role in oligodendrocytes, was identified as a potential mediator of Plexin-B3 signaling. Our results suggest that the interaction of extracellular HSPA5 with Plexin-B3 on oligodendrocytes, acting possibly through Nkx2.8, regulates oligodendrocyte maturation and myelination. This ligand and receptor interaction and a downstream molecule are newly added to the list of emerging signaling units controlling myelination.
Scalable distributed control for hybrid AC-DC microgrids with adaptive load management
MuseRAG++: a deep retrieval-augmented generation framework for semantic interaction and multi-modal reasoning in virtual museums
Wetting as an Emergent Property of Water: Reformulating Young’s Equation on Molecular Grounds
Feature-weighted maximum representative subsampling
Abstract In the social sciences, it is often necessary to debias studies and surveys before valid conclusions can be drawn. Debiasing algorithms enable the computational removal of bias using sample weights. However, an issue arises when only a subset of features is highly biased, while the rest are already representative. Algorithms need to substantially alter the sample distribution to handle a few highly biased features, which can, in turn, introduce bias into otherwise representative variables. To address this issue, we developed a method that uses feature weights to minimize the impact of highly biased features on the computation of sample weights. Our algorithm is based on Maximum Representative Subsampling (MRS), which debiases datasets by iteratively removing elements from a non-representative sample to align it with a representative one. The new algorithm, named feature-weighted MRS (FW-MRS), decreases the emphasis on highly biased features, allowing it to retain more instances for downstream tasks. The feature weights are derived from the feature importance of a domain classifier trained to differentiate between the representative and non-representative datasets. We validated FW-MRS using eight tabular datasets, each of which we artificially biased. Biased features can be important for downstream tasks, and focusing less on them could reduce generalization. For this reason, we assessed the generalization performance of FW-MRS on downstream tasks and found no statistically significant differences. Additionally, FW-MRS was applied to a real-world dataset from the social sciences. The source code is available at https://github.com/kramerlab/FeatureWeightDebiasing .
Electrosynthesis of Ethylene Glycol from Methanol via Oxidative C–C Coupling
Correction: PIGN spatiotemporally regulates the spindle assembly checkpoint proteins in leukemia transformation and progression
Discovery of a Robust Ru <sub>1</sub> –O–Ce Single Atom Catalyst for Coke-Free Dry Reforming of Methane
High-Fidelity Backpropagation through Primate Foveal Cones
Primate vision has exceptionally high spatial acuity and contrast sensitivity. This performance originates in specialized photoreceptors of the fovea. These cones transduce light into electrical signals in the outer segment, and convey these signals to the presynaptic terminal for transmission. Backpropagating signals are also possible, as the terminal receives inputs. Such signals could influence phototransduction itself. To test this idea, we recorded electrophysiologically from both ends of single cones dissociated from the macaque fovea (either sex). We found that backpropagation was effective despite the extreme slenderness and length of these cells. Backpropagation was also effective in a passive compartmental model, indicating that amplification by voltage-gated channels is not required. We then modeled foveal cones receiving terminal inputs from retinal networks. Despite faithful backpropagation of these inputs, they appear unlikely to influence phototransduction. Thus, even though foveal cones exhibit effective backpropagation, their encoding of visual information may remain compartmentalized.