Search Results (801)

This paper starts with the transition from classical physics to quantum mechanics which was greatly aided by the concept of phase space. The role of canonical transformations in quantum mechanics is addressed. The Wigner phase-space distribution function is then defined which arises from the formulation of the density matrix, followed by the harmonic oscillator in phase space. Coherent and one- and two-mode squeezed states of light as well as the squeezed vacuum are discussed in the phase-space picture. Attention is also drawn to the fact that squeezed states naturally generate entanglement between the two-modes. Coupled harmonic oscillators are also elucidated in connection with the Wigner phase space. Note that the phase-space picture of quantum mechanics has become an important scientific language for the rapidly expanding field of quantum optics. Here, we mainly focus on the simplest form of the Wigner function, which finds application in many branches of quantum mechanics. We make use of several symmetry groups such as Lorentz groups, the symplectic group in two and four dimensions, and the Euclidean group. The decoherence problem of an optical field is examined through a reformulation of the Poincaré sphere as a further illustration of the density matrix. Full article

In the era of big data and multimedia communication, securing color images against unauthorized access and attacks is a pressing challenge. While quaternion-based models provide a unified representation for color images, most existing encryption schemes rely on single-image frameworks or lack the mathematical rigor to ensure both security and feasibility. To bridge this gap, this paper introduces a system of generalized Sylvester-type quaternion matrix equations as a novel encryption model. By using the equivalence canonical forms of five matrices arranged in a specific array, we provide necessary and sufficient conditions for the solvability of the generalized Sylvester-type quaternion matrix equation system, depending on the rank of the coefficient matrix. Numerical examples are provided to validate the obtained results. As an example of applications, we develop an encryption scheme for color images based on the proposed quaternion matrix equation system. Experimental results confirm the high feasibility of the proposed scheme. Notably, the proposed model supports dynamic key updates and multi-image secure transmission, making it highly adaptable for real-world applications. By integrating advanced quaternion matrix theory with practical image encryption, this work offers a scalable, secure, and mathematically sound approach to color image protection. Full article

Atherosclerosis (AS) is a disease characterized by chronic vascular wall inflammation and lipid deposition. Although lipid-lowering drugs such as statins have significantly reduced cardiovascular event rates, “residual inflammatory risk” remains a key factor driving disease progression and plaque rupture. As a central regulator of the inflammatory response, the nuclear factor-κappaB (NF-κB) signaling network comprises both canonical pro-inflammatory pathways and functionally more complex non-canonical pathways. Increasing evidence in recent years indicates that abnormal and sustained activation of the non-canonical NF-κB signaling pathway plays a pivotal role in driving plaque rupture. This review first elaborates on the shift in AS strategies from “lipid-lowering” to “anti-inflammatory” approaches, followed by an in-depth analysis of the molecular activation mechanisms of the NF-κB signaling pathway and its distinctiveness in the AS pathological process, along with its epigenetic regulation. It emphasizes how this pathway drives pathological angiogenesis and regulates vascular smooth muscle cell (VSMC) phenotypic switching and macrophage function, thereby forming a vicious cycle that amplifies inflammation and structural damage, ultimately leading to acute cardiovascular events. Finally, we systematically summarize current progress and challenges in drug development targeting the NF-κB pathway (e.g., targeting key kinases like NIK and IKKα), aiming to provide theoretical foundations and future directions for novel therapeutic strategies to stabilize coronary plaques and prevent acute coronary syndromes. Full article

In the Chinese Buddhist tradition, copying and printing sacred texts is considered a form of merit-making, or virtuous activity. One reason for the printing and circulation of books in the Buddhist tradition is the belief that one can gain merits. From the introduction of Buddhism into China, devotees copied, printed and disseminated sūtras to generate merit, a kind of spiritual goodness, which accumulates with each positive act. The author has gathered a large amount of data from libraries, museums and temples around the world that demonstrates how the imperial family members, concubines, court ladies, eunuchs, Buddhist monks and lay devotees supported the construction of the Buddhist canon. They believed that the printing of the Buddhist scriptures would grant them all kinds of merit, such as those who seek happiness in life now and happiness in the next life, or those who encounter disasters and difficulties in the present world. As this paper deeply delves into the sources of the editions of the Chinese Buddhist canon, we may further analyze the practice of merit-making hierarchically and horizontally. Full article

CK2α and CK2α’, two paralogous members of the human kinome, are catalytic subunits of protein kinase CK2. Together with the regulatory subunit CK2β, they form heterotetrameric holoenzymes. CK2 is the subject of efforts to develop effective and selective inhibitors. For this, secondary binding sites remote from the canonical ATP/GTP cavity are critical. A crystallographic fragment screening with CK2α’ crystals and an established molecular fragment collection was performed to identify new ligands at known or novel sites. It resulted in fourteen CK2α’/fragment structures. Five fragments were found at the CK2β interface of CK2α’ and three fragments at the established αD pocket, which exhibits subtle differences between CK2α and CK2α’; comparative co-crystallisations with CK2α showed that one of them binds to the αD pocket of CK2α’ exclusively. No fragments bound at the substrate-binding region of CK2α’, but a CK2α’ structure with dp10, a decameric section of the substrate-competitive inhibitor heparin, and the indenoindole-type ATP-competitive inhibitor 4w was determined. A comparison with a published CK2α/dp10 structure revealed features consistent with reports about substrate specificity differences between the isoenzymes: dp10 binds to CK2α’ and CK2α with opposite strand orientations, and the local conformations of the isoenzymes in the helix αD region are significantly different. Full article

The present research demonstrates the utility of the linear canonical transform (LCT) in constructing the characteristic function of real random variables. We refer to this construction as the linear canonical characteristic function (LCCF). The proposed LCCF aims to address the limitations of the classical characteristic function in both theoretical and applied aspects. Using this approach, we investigate its properties, such as Hermitian symmetry, continuity, convolution, and derivatives, which are generalized forms of the classical characteristic function in the literature. Finally, we implement the obtained results by calculating several probability density functions in the LCCF domains. Full article

Background/Objectives: Familial adenomatous polyposis (FAP) is an autosomal dominant disorder caused by pathogenic variants in the adenomatous polyposis coli (APC) gene. Its attenuated form (AFAP) is characterized by fewer colorectal polyps and later onset of colorectal cancer. We aimed to characterize the molecular effects of a novel APC gene variant (NM_000038.6: c.1620_1624delinsT) identified in a patient with AFAP. Methods: A 56-year-old man with the AFAP phenotype underwent germline testing via a multigene NGS panel, which identified a novel APC gene variant (NM_000038.6: c.1620_1624delinsT). In silico analyses predicted disruption of the canonical donor splice site and a frameshift followed by the introduction of a premature stop codon. The transcriptional impact of the identified APC gene variant was investigated by mRNA analysis. Results: mRNA analysis revealed two distinct APC transcripts: the first transcript led to a truncated protein (p.Leu540PhefsTer8), and the second transcript lacked exon 12, resulting in an in-frame 26 amino acid deletion of APC protein (p.Ala517_Gly542del). The transcript lacking exon 12 was more abundant than the transcript with a premature stop codon, likely due to degradation through nonsense-mediated decay. Conclusions: The APC gene variant (NM_000038.6: c.1620_1624delinsT) exhibits a dual transcriptional effect, revealing its pathogenic role in AFAP. This study highlights the diagnostic value of combined DNA–RNA germline testing for improving the clinical classification of novel APC gene variants and their genotype–phenotype correlations in FAP. Full article

Ferroptosis is an iron-dependent, oxidative form of regulated cell death that has emerged as a therapeutic vulnerability in glioblastoma; however, the mitochondrial determinants that govern ferroptotic sensitivity remain poorly defined. Cytochrome c oxidase (CcO/Complex IV), a key regulator of mitochondrial respiration, contains two isoforms of subunit IV (COX4): COX4-1, a housekeeping isoform, and COX4-2, a stress-inducible variant. We previously found that COX4-1 expression protects glioma cells from erastin-induced ferroptosis, suggesting that mitochondria influence cell-death decisions independently of canonical ferroptotic regulators. Here, we used CRISPR-generated POLG-knockout ρ⁰ cells and transmitochondrial cybrids to isolate mitochondrial from nuclear contributions to ferroptosis sensitivity. Cybrids reconstituted with COX4-1-containing mitochondria restored CcO activity and recapitulated the ferroptosis-resistant phenotype, whereas COX4-2 cybrids remained insensitive to erastin. COX4-1 cybrids exhibited reduced labile iron, diminished cystine uptake, and low expression of SLC7A11 and GPX4, yet underwent apoptosis rather than ferroptosis upon erastin treatment. These findings demonstrate that mitochondrial COX4-1 rewires redox metabolism and diverts cell-death signaling away from ferroptosis toward apoptosis. Our results identify isoform-specific mitochondrial composition as a previously unrecognized determinant of regulated cell death and highlight COX4-1-driven mitochondrial remodeling as a potential mechanism of therapeutic resistance in glioblastoma. Full article

The role of alternative nucleic acid structures (ANS) in biology is an area of increasing interest. These non-canonical structures include the Z-DNA and Z-RNA duplexes (ZNA), the three-stranded triplex, the four-stranded G-quadruplex (GQ), and i-motifs. Previously, the biological relevance of ANS was dismissed. Their formation in vitro often required non-physiological conditions, and there was no genetic evidence for their function. Further, structural studies confirmed that sequence-specific transcription factors (TFs) bound B-DNA. In contrast, ANS are formed dynamically by a subset of repeat sequences, called flipons. The flip requires energy, but not strand cleavage. Flipons are enriched in promoters where they modulate transcription. Here, computational modeling based on AlphaFold V3 (AF3), under optimized conditions, reveals that known B-DNA-binding TFs also dock to ANS, such as ZNA and GQ. The binding of HLH and bZIP homodimers to Z-DNA is promoted by methylarginine modifications. Heterodimers only bind preformed Z-DNA. The interactions of TFs with ANS likely enhance genome scanning to identify cognate B-DNA-binding sites in active genes. Docking of TF homodimers to Z-DNA potentially facilitates the assembly of heterodimers that dissociate and are stabilized by binding to a cognate B-DNA motif. The process enables rapid discovery of the optimal heterodimer combinations required to regulate a nearby promoter. Full article

A new class of plant phosphotransfer proteins belonging to the multistep phosphorelay (MSP) system implicated in phytohormone cytokinin signaling was discovered based on large-scale bioinformatics methods. Unlike the canonical soluble nucleo-cytosolic forms, these proteins were predicted to have transmembrane (TM) domains and, apparently, should be localized on some kind of cell membrane. To date, 94 predicted TM-containing phosphotransmitter (TM-HPt) homologs were found in 62 plant species belonging to different clades, taxa, and groups of embryophytes: bryophytes, gymnosperms, and mono- and dicotyledons. The conserved HPt motif with phosphorylatable histidine was preserved in most of the TM-HPts under study, which allowed us to consider these proteins potentially active in MSP signaling. For the identified TM-HPts, a Bayesian analysis at the DNA level was performed, and a relevant phylogenetic tree was constructed. According to evolutionary relationships, plant TM-HPts were divided into two main groups corresponding to Arabidopsis AHP1-3,5,6, and AHP4 orthologs. Transcriptomic analysis confirmed the expression of most of the investigated TM-HPt-encoding genes. Their moderate-to-low overall transcription rate may be a consequence of inducible and/or tissue-specific expression. Using molecular modeling methods, a variety of potential spatial organizations of several such proteins are demonstrated. The ability of the uncovered TM domains to tether HPts to membranes was supported by molecular dynamic simulation. Possible roles of TM-HPts as modulators of the MSP signaling pathway and corresponding putative mechanisms of their action are suggested. Full article

Dental pain often arises from the compromised integrity of the tooth pulp due to dental injury or caries. The dentin–pulp complex has long been considered to be central to the unique biology of dental pain. Most trigeminal ganglion afferents projecting into tooth pulp are myelinated neurons, which lose their myelination at the site of peripheral dentin innervation. The pulpal afferents likely combine multiple internal and external stimuli to mediate nociception and maintain pulp homeostasis. Transient receptor potential (TRP) ion channels in neurons and odontoblasts, along with mechanosensitive ion channels such as Piezo, form a key molecular hub for pulpal nociception by sensing thermal, chemical, and hydrodynamic stimuli. Among these, TRP vanilloid 1 (TRPV1) mediates nociception and the release of calcitonin-gene-related peptides (CGRPs), while TRP canonical 5 (TRPC5) mediates cold pain. TRP melastatin 8 (TRPM8) mediates the transduction of hyperosmotic stimuli. Pulpitis elevates endogenous TRPV1 and TRPA1 agonists, while inflammatory mediators sensitize TRP channels, amplifying pain. CGRP recruits immune cells and promotes bacterial clearance and reparative dentinogenesis, yet the roles of TRP channels in these processes remain unclear. Future studies should use advanced multi-omics and in vivo or organotypic models in animal and human teeth to define TRP channel contributions to pain, immune responses, and regeneration. Understanding neuronal and non-neuronal TRP channel interactions and their integration with other ion channels may enable novel analgesic and regenerative strategies in dentistry. Full article

Synapses, abundant in the brain, are structures needed for life. Our Introduction, based on the forms of such structures published few decades ago, helped in developing recent concepts of health and diseases. Growing axons govern their growth by cell-to-cell communication, axon guidance, and synapse orientations. The assembly of synapses requires the organization and function of pre-synaptic and post-synaptic neuronal terminals with a liquid–liquid phase, governed by Ca²⁺ responses of thin astrocyte domains. Upon synapse stimulation, the clefts expand up to several folds while pre- and post-synaptic thickness remains unchanged. In additional responses, neurons co-operate with astrocytes and extracellular vesicles (EVs), the latter dependent on extracellular and intracellular spaces. Astrocyte and microglia cells and/or EV secretions induce neurons by various effects including traveling changes. Pre-synaptic responses are defined as canonical if based on neurotransmitter release; non-canonical if they are without release and are discharged by EVs, not neurotransmitters. Health and diseases depend on other general properties, such as those defined molecularly. Among neurodegenerative diseases, attention is specified by various properties of Alzheimer’s and other diagnoses. Critical identifications can be due to astrocyte and microglia cells or multiple effects induced by EVs. At present, the complexity of therapies, although of limited success, is developing innovative initiatives. Full article

Butidae is a family of teleost fishes with diverse morphological and ecological adaptations, including the marbled goby (Oxyeleotris marmorata), a large species of high economic value in Southeast and East Asia. The previous mitogenomic studies on cultured populations of O. marmorata from non-native habitats have provided limited insights into genetic divergence, structural variation, and evolutionary relationships. Hence, this study presented the complete mitochondrial genome of O. marmorata from its native habitat in Indonesia, providing structural characterization, assessment of genetic diversity, and matrilineal phylogenetic analysis. The circular mitogenome was 16,525 bp, comprising 37 genes and a non-coding control region (CR). The gene organization and strand distribution were conserved among Oxyeleotris species, with 28 genes on the heavy strand and nine on the light strand, and a pronounced A+T compositional bias. The comparative analyses of O. marmorata (from both native and cultured habitats) and Oxyeleotris lineolata mitogenomes revealed minor variations in intergenic spacers, gene overlaps, protein-coding gene (PCGs) lengths, and codon usage patterns. Conversely, the nonsynonymous and synonymous substitution ratios observed in species of the family Butidae and its closest related family (Eleotridae) indicate strong purifying selection in the present dataset. Notably, the ATG was the predominant start codon, whereas the COI gene utilized GTG, and amino acid composition analysis demonstrated high frequencies of arginine, leucine, and serine. Most transfer RNAs retained the canonical cloverleaf secondary structure except for trnS1, which lacked a functional dihydrouridine arm, whereas the CR contained four conserved sequence blocks with variable nucleotide motifs and no detectable tandem repeats. The haplotype analysis of native (Indonesia) and introduced populations (China) highlighted three haplotypes with high diversity (Hd = 1.0000) and substantial nucleotide variation (π = 0.6667). The genetic divergence across 13 PCGs was gene-specific, with COI and ND5 showing the highest variation, while ND4L and ATP8 were highly conserved. The phylogenetic analyses based on concatenated 13 PCGs using both Bayesian Inference and Maximum Likelihood methods revealed that Oxyeleotris forms a monophyletic clade and is closely related to Bostrychus sinensis. In addition, the broader phylogenetic framework inferred the matrilineal relationships within the family Butidae and its closest related family, Eleotridae. This study also recommends expanding analyses to include the mitogenomes of the remaining 17 Oxyeleotris species, together with comprehensive genomic data, to further elucidate their genetic architecture, evolutionary history, and ecological adaptability across diverse aquatic ecosystems. Full article

In the mid to late Tang Dynasty, the compilation and reproduction of the tripiṭaka (Tripitaka) was directly intervened and controlled by the authorities, surpassing its own religious function and becoming an important political expression form with Buddhist elements. In the 10th century, with the collapse of the Tang Empire, the Liao, Song, and Western Xia coexisted within its original territory. At the same time, the political situation in the Korean Peninsula and Vietnam has undergone drastic changes. Within this period, the Song and Liao empires formed a dual core pattern, and the printing and issuing of the Tripitaka with strong political attributes became an important means of competition between the two sides. From the end of the 10th century to the early 11th century, the Song was the first to complete the Kaibao Canon, maintaining the monopoly of the printed Tripitaka during this period and taking it as an important way to establish the world order dominated by the Song and consolidate its relationship with neighboring political powers. Japan, which was not part of the tribute system dominated by the Song, became a target that Emperor Taizong of Song vigorously sought. Under the guidance of this political logic, the Song court, which advocated Daoism, also wanted to voluntarily issue the newly printed Daoist Canon to Vietnam, to exert its religious and political influence. After the mid-11th century, with the establishment of the Khitan Canon, the competition began between the Liao and Song dynasties over the printing and distribution of the Tripitaka. As one of the dual core patterns, the Liao attempted to challenge the monopoly position of the Song’s Kaibao Canon and the cultural hegemony behind it. In this situation, Goryeo, which was wavering between the Liao and Song, became the battlefield of competition between the two empires, presenting complex changes in terms of whether to accept the Tripitaka and their reception standards. In the late 11th century, the Goryeo and the Western Xia almost coincidentally embarked on the so-called “third path”—the construction of their own independent Tripitaka. Due to their limited positions in the political landscape of East Asia at that time, these Tripitakas were not granted to neighboring regimes outside their borders after completion, and therefore did not have international significance. It should be noted that although the positioning of the Goryeo Canon was different from that of the Song and Liao editions, it still belonged to the competition among the same language; the emergence of the Tangut Canon marked a new possibility and opened the way for future Tibetan and Manchu Canons. Briefly, the printed Tripitaka was deeply involved in the multilateral interactions of political powers in East Asia from the 10th to the 13th Century. Full article

Background: Adolescence is a crucial stage of development marked by significant biological, social, and emotional changes that influence mental health and well-being. This study aims to (a) assess the relationship between resilience, life satisfaction, and mental well-being in adolescents aged between 10 and 18 years who are attending 5th to 12th grade in the central region of mainland Portugal, and (b) assess the quality of fit of a structural mediation model in which life satisfaction mediates the relationship between resilience and mental well-being. Methods: A total of 589 adolescents participated in the study and responded to the Escala de Avaliação do Eu Resiliente, the Multidimensional Life Satisfaction Scale for Adolescents, and the Mental Health Continuum–Short Form. Descriptive analyses, ANOVA, canonical correlation analysis, and structural equation modeling with mediation were carried out. Results: A high canonical correlation (r = 0.873, p < 0.001) was found between resilience and well-being/life satisfaction. Mediation analysis revealed that life satisfaction partially mediates the relationship between resilience and positive mental health (r² = 0.34), indicating direct and indirect effects. Conclusions: These results suggest that more resilient adolescents tend to report higher levels of life satisfaction and well-being, which reinforces the importance of promoting resilience and life satisfaction as protective factors for mental health during adolescence. Full article