Search Results (474)

Background: Deprivation of sleep (DS) might affect mood and cognitive abilities, including psychomotor functions (PF). Molecular mechanisms underlying these effects remain unclear, though studies suggest that the circadian rhythm plays a role. Methods: Seventy participants underwent polysomnography (PSG) and DS. PF was evaluated using Bimanual Eye–Hand Coordination Test (BEHCT). Mood, PF, and clock gene expression (Circadian Locomotor Output Cycles Kaput (CLOCK), Brain and Muscle ARNT-Like 1 (BMAL1), Period Circadian Regulator 1 (PER1), Cryptochrome Circadian Regulator 1 (CRY1), Nuclear Receptor Subfamily 1 Group D Member 1 (NR1D1), and Neuronal PAS Domain Protein 2 (NPAS2)) were analyzed post-PSG and post-DS. Mood changes after DS classified participants as responders (RE) or non-responders (NR). Results: In NRs, but not REs, the BEHCT error count positively correlated with the expression of BMAL1, CRY1, PER1, NR1D1 (R = 0.60, p = 0.002; R = 0.49, p = 0.018; R = 0.57, p = 0.023; and R = 0.53, p = 0.011, respectively), with PER1 explaining its variability in 57.8% (b = 0.174, R² = 0.578, F = 20.144, and p < 0.001). Conclusions: Obtained results suggest that altered clock gene expression may contribute to individual differences in mood and PF following DS. Full article

As the mainstream technology solution for deep imaging LiDAR, dToF measurement has been widely applied in emerging fields such as environmental perception and obstacle recognition, 3D terrain reconstruction, real-time motion capture, and drone obstacle avoidance navigation due to its advantages of high resolution, long-range detection capability, and high sensitivity. In order to adapt to functional applications in different scenarios, the resolution of TDC needs to be adjustable and can work normally in different environments. In view of this, this article studies the pixel array and TDC circuit in the chip and locks a voltage-controlled ring oscillator (VCRO) with the same structure as the pixel to a fixed frequency through a PLL structure. Then copy the control voltage of the locked VCRO to the control terminal of the TDC in each pixel. In an ideal situation, this control voltage can make the oscillation frequency of VCRO within the pixel consistent with the locking frequency of VCRO within the PLL, and insensitive to changes in PVT. This study developed a module expandable 16 × 16-pixel array dToF sensor chip based on TDC architecture using CMOS technology. Finally, six configurable 16 × 16-pixel subarrays were integrated and constructed into a 32 × 48 large-scale dToF sensor chip through modular splicing. The top-level layout design was completed using SMIC 180 nm technology, with a layout area of 5285 µm × 3669 µm. Post-simulation verification showed that, under the testing conditions of a 400 MHz system clock and a 33.3 kHz frame rate, the dToF chip system performance indicators were: time measurement resolution of 156 ps, DNL < 1 LSB, INL < 0.85 LSB, and absolute ranging accuracy better than 2.5 cm. Full article

To explore the function of the period gene (Ec-per) in Exopalaemon carinicauda, we cloned the gene of 4611 bp with a 5′UTR of 201 bp, a 3′UTR of 813 bp, and an ORF of 3597 bp encoding 1198 amino acids. The predicted protein includes two PAS and one PERIOD domain. qPCR analysis revealed that Ec-per was expressed across all tissues tested at different developmental stages and during both embryonic and larval stages. Moreover, Ec-per oscillated rhythmically under different conditions of light-to-dark (L:D) ratios, including continuous darkness (0 L:24 D), where changes in the photoperiod influenced amplitude and phase shifts. The knockdown of Ec-per mRNA significantly reduced the expression of the circadian-related genes timeless (tim) and cryptochrome 1 (cry1) (p < 0.05). This suggests that Ec-per is an endogenous clock gene that may participate in molecular feedback loops and synergistically regulate the circadian rhythms through interacting with tim and cry1. RNA interference of Ec-per also markedly downregulated ecdysone receptor mRNA (p < 0.05), suggesting a positive role in the ovarian development of E. carinicauda. In situ hybridization further demonstrated that Ec-per is involved in oocyte proliferation and the accumulation of exogenous nutrients. This study provides new insights for promoting ovarian development and artificial breeding in crustaceans through optimized light-cycle management. Full article

Due to the influence of factors such as satellite jitters, orbital errors, star sensor errors, and satellite clock errors, significant geometric systematic errors often exist among multi-view satellite images. This is common for multi-view, cross-orbit satellite data, where complex nonlinear systematic errors are present, making it difficult to correct them using traditional error compensation models. To achieve high-precision block adjustment, this paper proposes a direct adjustment and optimization method for Rational Function Model (RFM) parameters based on prior soft constraints. In this method, the original RFM parameters are used as prior information, which is formulated as prior information soft constraint equations in the adjustment model, aiming at effectively addressing the ill-posed problems. By directly optimizing part or all of the RFM parameters, this method can obtain stable adjustment results in scenarios of complex systematic errors. Experiments among WorldView-3, GaoFen Multi-mode, ZY-3 (Ziyuan-3), and GaoFen-7 satellite data show that, when using multi-view, cross-orbit satellite data and with sufficient and evenly distributed tie points, the proposed full-parameter RFM optimization method and the adaptive RFM optimization method can achieve the highest adjustment accuracy. On the other hand, when using in-track satellite data, the affine systematic error compensation model achieves the highest accuracy, while the adaptive RFM optimization method can achieve comparable accuracy. Therefore, the research results can be applied to intelligent processing scenarios for multi-view, cross-orbit satellite data, such as multi-temporal change detection and multi-view, cross-orbit satellite 3D modeling. Full article

Circadian disruption (CD) has emerged as a critical factor compromising human health in contemporary society. Increasing evidence suggests that disturbances in circadian rhythms are involved in the pathogenesis of neurodegenerative diseases, such as Alzheimer’s disease (AD). The hyperphosphorylation of tau and the deposition of amyloid-β (Aβ) are recognized as major pathological hallmarks of AD. In this study, we aimed to explore the impact of long-term CD on AD-like pathological changes and to explore the underlying molecular mechanisms using a mouse model. To mimic the CD experienced by shift workers, mice were subjected to lighting conditions involving repeated reversals of the light–dark cycle. In this study, qPCR was to employed detect the expression profile of clock genes in the hippocampus. Subsequently, Western blotting and immunohistochemical analyses were used to evaluate AD-like pathological changes in the hippocampus following CD. For elucidating the underlying mechanisms, we assessed circadian expression patterns of major neurotransmitters, activation of microglia and astrocytes, and alterations of tight junction proteins within the hippocampus. Our findings demonstrated that light–dark cycle disruption triggered CD in mice, and then CD led to increased expression of Aβ protein and tau hyperphosphorylation. CD significantly disrupted the circadian expression profiles of hippocampal clock genes and major neurotransmitters, induced microglial and astrocytic activation, and decreased the expression of the tight junction proteins zonula occludens-1 and occludin in the hippocampus. These results suggest that changes in the light–dark cycles induced abnormal expression of hippocampal clock genes involved in circadian rhythm regulation, suggesting that the body is in a state of endogenous CD. CD induces AD-like pathological changes in mice, potentially mediated by dysregulated circadian oscillations of clock genes, neuroinflammation, loss of key blood–brain barrier proteins, and disturbed neurotransmitter expression in the hippocampus. Collectively, this study underscores the importance of circadian stability for brain health, and highlights the necessity for deeper exploration into the connection between AD and CD. Full article

Computer-based engineering design tools can quicken the cadence for machine design, which enables companies to compete better in the global marketplace. The application of nonlinear optimization and tradespace analysis methods allows the exploration of design variables within dynamic mechanisms. In this paper, the design of a classical machine, the Seth Thomas pendulum street clock, which offered precision timekeeping and time display at the turn of the 20th century, will be investigated from a modern perspective. A mathematical model serves as the basis for the genetic algorithm optimization method to assess the system design in terms of accuracy, mass, quality factor, and bending stress. To validate the model, experimental data was collected on a 1906 Seth Thomas Model 04 movement. The engineering study findings indicate that the target accuracy, quality factor, and bending stress can be achieved with pendulum mass and gear thickness reductions of 1.4% and 50.3%, respectively. The tradespace exploration offers a visualization of the machine’s performance per design variable adjustments for greater insight into the original solution and subsequent recommended changes. Overall, this mechanical machine review enables an assessment of original design choices made over a century ago and provides an awareness of engineering’s progress during this period. Full article

As we become older, systems throughout the body gradually decline in function. Contributing factors include the accumulation of senescent cells and the dysfunction and exhaustion of stem and progenitor cells. A promising approach to mitigate these changes and enhance cellular function in aged animals is the discovery that differentiated cells retain plasticity, enabling them to revert to pluripotent states when exposed to Yamanaka factors. This method has shown promise in models of rapid aging, and recent studies have demonstrated notable life extension in both flies and mice. These findings, along with the development of senolytics and aging clocks, could revolutionize aging research and interventions. Here, we review recent discoveries in the field and propose new directions for intervention discovery. Full article

As space systems evolve towards cis-lunar missions and beyond, the demand for precise yet low-size, -weight, and -power (SWaP) clocks and synchronization methods becomes increasingly critical. We introduce a novel clock synchronization approach based on the Kuramoto oscillator model that facilitates the creation of an ensemble timescale for satellite constellations. Unlike traditional ensembling algorithms, the proposed Kuramoto method leverages nearest-neighbor interactions to achieve collective synchronization. This method simplifies the communication architecture and data-sharing requirements, making it well suited for dynamically connected networks such as proliferated low Earth orbit (pLEO) and lunar or Martian constellations, where intersatellite links may frequently change. Through simulations incorporating realistic noise models for small-scale atomic clocks, we demonstrate that the Kuramoto ensemble can yield an improvement in stability on the order of 1/√N, while mitigating the impact of constellation fragmentation and defragmentation. The results indicate that the Kuramoto oscillator-based algorithm can potentially deliver performance comparable to established techniques like Equal Weights Frequency Averaging (EWFA), yet with enhanced scalability and resource efficiency critical for future spaceborne PNT and communication systems. Full article

Background/Objectives: Parkinson’s disease (PD) is an adult-onset neurodegenerative disorder whose pathogenesis is still not completely understood. Several lines of evidence suggest that alterations in epigenetic architecture may contribute to the development of this condition. Here, we present a pilot DNA methylation study from peripheral blood in a cohort of Sicilian PD patients and matched controls. Peripheral tissue analysis has previously been shown to reflect molecular and functional profiles relevant to neurological diseases, supporting their validity as a proxy for studying brain-related epigenetic mechanisms. Methods: We analyzed 20 PD patients and 20 healthy controls (19 males and 21 females overall), matched for sex, with an age range of 60–87 years (mean 72.3 years). Peripheral blood DNA was extracted and processed using the Illumina Infinium MethylationEPIC v2.0 BeadChip, which interrogates over 935,000 CpG sites across the genome, including promoters, enhancers, CpG islands, and other regulatory elements. The assay relies on sodium bisulfite conversion of DNA to detect methylation status at single-base resolution. Results: Epigenome-wide association study (EWAS) data allowed for multiple levels of analysis, including immune cell-type deconvolution, estimation of biological age (epigenetic clocks), quantification of stochastic epigenetic mutations (SEMs) as a measure of epigenomic stability, and differential methylation profiling. Immune cell-type inference revealed an increased but not significant proportion of monocytes in PD patients, consistent with previous reports. In contrast, epigenetic clock analysis did not reveal significant differences in biological age acceleration between cases and controls, partially at odds with earlier studies—likely due to the limited sample size. SEMs burden did not differ significantly between groups. Epivariations reveal genes involved in pathways known to be altered in dopaminergic neuron dysfunction and α-synuclein toxicity. Differential methylation analysis, however, yielded 167 CpG sites, of which 55 were located within genes, corresponding to 54 unique loci. Gene Ontology enrichment analysis highlighted significant overrepresentation of pathways with neurological relevance, including regulation of synapse structure and activity, axonogenesis, neuron migration, and synapse organization. Notably, alterations in KIAA0319, a gene involved in neuronal migration, synaptic formation, and cortical development, have previously been associated with Parkinson’s disease at the gene expression level, while methylation changes in FAM50B have been reported in neurotoxic and cognitive contexts; our data suggest, for the first time, a potential epigenetic involvement of both genes in Parkinson’s disease. Conclusions: This pilot study on a Sicilian population provides further evidence that DNA methylation profiling can yield valuable molecular insights into PD. Despite the small sample size, our results confirm previously reported findings and highlight biological pathways relevant to neuronal structure and function that may contribute to disease pathogenesis. These data support the potential of epigenetic profiling of peripheral blood as a tool to advance the understanding of PD and generate hypotheses for future large-scale studies. Full article

The “athlete’s heart” phenotype, featuring resting bradycardia, has traditionally been viewed as a benign adaptation. However, emerging evidence associates prolonged, high-intensity endurance training with an increased risk of clinical sinoatrial node dysfunction. This systematic review synthesizes evidence on exercise-induced intrinsic Sinoatrial Node (SAN) electrophysiological remodelling and evaluates its dual nature along the adaptation–pathology continuum. Following PRISMA guidelines, a systematic search of PubMed, Web of Science, and Google Scholar (2000–2025) identified 17 eligible studies. Analysis revealed that in humans, rodents, and rabbits, exercise induces intrinsic SAN electrophysiological remodelling—a “membrane clock” reset characterized by coordinated downregulation of pacemaker currents, notably Hyperpolarization-activated cyclic nucleotide-gated cation channel (I_f), via the Nkx2.5-miR-423-5p transcription factor pathway. Evidence for “calcium clock” involvement remains inconsistent. In contrast, large animal models (e.g., dogs, horses) show only parasympathetic-mediated bradycardia without intrinsic remodelling. Training loads may induce structural changes (e.g., fibrosis), providing an anatomical substrate for pathology. Moderating factors such as training type and ageing contribute to a phenotype of “acquired SAN reserve reduction. Exercise-induced intrinsic SAN remodelling is a physiological adaptation mechanism that, under certain conditions, can cross a threshold to become a pathological cause of clinical dysfunction. Recognizing this continuum is essential for risk stratification and future therapeutic innovation. Full article

Satellite clock bias exhibits complex, time-varying periodic characteristics due to environmental disturbances. Accurate modeling and prediction of periodic terms play a crucial role in improving the precision and stability of short-term predictions. Traditional models such as spectral analysis model (SAM) estimate the frequency, amplitude, and phase of periodic terms through global fitting, which limits their ability to adapt to abrupt changes at the prediction boundary. To address this limitation, this paper proposes an improved spectral analysis model (IM-SAM) based on the inaction method (IM). The model employs IM to extract the instantaneous frequency, amplitude, and phase parameters of periodic terms precisely at the data endpoint, and utilizes the parameters of periodic terms at the data endpoint for prediction, effectively suppressing periodic fluctuations in prediction errors. Experimental results based on real GPS clock bias data demonstrate that the root mean square (RMS) of IM-SAM prediction errors is reduced by 19.14%, 14.39%, and 10.48% for 3 h, 6 h, and 12 h prediction tasks, respectively, compared with SAM. Furthermore, a kinematic precise point positioning experiment was performed using IM-SAM-predicted clock products and compared with the predicted half of IGS ultra-rapid clock products. The RMS of position error was reduced by 14.3%, 12.6%, and 7.9% in the east, north, and up directions, respectively. These results demonstrate the practical effectiveness and accuracy of IM-SAM in real-time clock prediction and GPS positioning applications. Full article

Disruptions in the circadian clock and their link with cancer constitute a growing area of research, as evidenced by the steadily increasing number of articles on the topic. While the genes associated with circadian rhythms are relatively well characterized, the complexity of their regulation remains an important direction for study. It has been demonstrated that the interplay between genes, their expression products and external factors, such as environmental pollutants and human behavioral patterns, can lead to pathological changes, including metabolic diseases and cancer. Investigation of circadian cycle deregulations can not only provide a better understanding of carcinogenicity mechanisms and risk assessment but also create possibilities to identify new chemotherapeutics targeted at neoplastic cells. REV-ERBs and RORs are two groups of circadian clock-related nuclear factors that are examined regarding their interactions with small-molecule modulators of the circadian clock. These can act as either receptor agonists or inverse agonists, depending on the specific characteristics of a particular cancer. This review therefore summarizes and systematizes existing knowledge regarding the effectiveness of circadian modulators as chemotherapy agents, with the aim of indicating further directions for research in the field. Full article

As embedded and IoT systems demand secure and compact encryption, developing cryptographic solutions that are both lightweight and efficient remains a major challenge. Many existing AES implementations either lack flexibility or consume excessive hardware resources. This paper presents an area-efficient and flexible AES-128 implementation based on a hardware/software (HW/SW) co-design, specifically optimized for platforms with limited hardware resources, resulting in reduced power consumption. In this approach, key expansion is performed in software on a lightweight MicroBlaze processor, while encryption and decryption are accelerated by dedicated hardware IP cores optimized at the Look-up Table (LuT) level. The design is implemented on a Xilinx XC5VLX50T Virtex-5 FPGA, synthesized using Xilinx ISE 14.7, and tested at a 100 MHz system clock. It achieves a throughput of 13.3 Gbps and an area efficiency of 5.44 Gbps per slice, requiring only 2303 logic slices and 7 BRAMs on a Xilinx FPGA. It is particularly well-suited for resource-constrained applications such as IoT nodes, secure mobile devices, and smart cards. Since key expansion is executed only once per session, the runtime is dominated by AES core operations, enabling efficient processing of large data volumes. Although the present implementation targets AES-128, the HW/SW partitioning allows straightforward extension to AES-192 and AES-256 by modifying only the software Key expansion module, ensuring practical scalability with no hardware changes. Moreover, the architecture offers a balanced trade-off between performance, flexibility and resource utilization without relying on complex pipelining. Experimental results demonstrate the effectiveness and flexibility of the proposed lightweight design. Full article

The inverter is the key element that converts the intermittent DC power of the PV array into a quality AC flow to the grid and simultaneously performs functions such as power factor control, reactive services, and grid code compliance. Therefore, the detailed operating profile of the inverter, how the power, dynamics, power quality, and efficiency evolve over time, is critical for both the scientific understanding of the system and the daily operation (O&M). Monitoring only aggregated energy indicators or single KPIs (e.g., PR) is often insufficient: it does not distinguish weather-related variations from technical limitations (clipping, curtailment), does not show dynamic loads (ramp rate), and does not provide confidence in the quality of the injected energy (PF, P–Q behavior). These deficiencies motivate research that simultaneously covers the physical side of the conversion, the operational dynamics, and the climatic reference of the resource. The analysis covers the window of 25 January–15 April 2025 (winter→spring). Due to the pronounced seasonality of the solar resource and temperature regime, all quantitative results and conclusions regarding efficiency, dynamics, clipping, and degradation are valid only for this window; generalizations to other seasons require additional data. In the next stage, we will add ≥12 months of data and perform a comparable seasonal analysis. Full specifications of the measuring equipment (DC/AC current/voltage, clock synchronization, separate high-frequency $PQ$-logger) and quantitative uncertainty estimates, including distribution to key indicators ($\eta$, $PR$, $THD$, $I_{DC}$), are presented. The PVGIS per-kWp climate reference is anchored to the nameplate DC peak and cross-checked against percentile scaling; $a\pm \epsilon$ scale error shifts $PR$ by $\epsilon$ and changes $\Delta E$ proportionally only on hours with $\widehat{P}>P$. The capacity for the climate reference (PVGIS per-kWp) is calibrated to the tabulated DC peak power $C_{cert}$ and is cross-validated using a percentile scale ($Q_{0.99}$). Full article

Background: White adipose tissue (WAT) exhibits diurnal oscillations regulated by clock genes, which autonomously control its functionality. These rhythms are modulated by the central clock and external factors, such as light exposure and diet. Flavanols, phenolic compounds known for their beneficial metabolic effects, have been shown to modulate the expression of clock genes. This study explored the impact of flavanols on clock gene expression in WAT explants from lean and obese rats under changes in light/dark cycles. Methods: WAT explants were obtained from 24 Fischer rats fed a standard diet (STD) or cafeteria diet (CAF) for seven weeks. During the final week, rats were changed to short (6 h of light, L6) or long (18 h of light, L18) photoperiods. CAF-fed rats were also administered a grape seed (poly)phenol-rich extract (GSPE) (25 mg/kg) or vehicle (VH). After sacrifice, WAT explants were collected every 6 h starting at 8 a.m. the following day (CT0, CT6, CT12, CT18, and CT24). Results: The results showed that under L18 conditions, STD-fed rats displayed oscillations in Bmal1, Cry1, Per1, and Rev-erbα clock gene expression, whereas many of these rhythms were disrupted under L6 conditions. Moreover, the administration of the CAF diet also resulted in the loss of clock gene circadian oscillations in the WAT explants. GSPE administration restored the oscillation of these clock genes under L18 and L6 conditions. Conclusions: These findings highlight the potential zeitgeber role of flavanols in modulating WAT peripheral clocks and their capacity to improve metabolic and circadian regulation under conditions of diet- and photoperiod-induced disruption. Full article