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Batalin–Fradkin–Vilkovisky quantization of Einstein gravity with off-diagonal solutions encoding Hořava type generating functions
No full textWe develop and apply the Batalin–Fradkin–Vilkovisky (BFV) formalism for the covariant quantization of generic off-diagonal solutions of the Einstein equations in general relativity (GR). In the classical regime, such nonholonomic configurations are formulated entirely within GR and are characterized by nonlinear symmetries of generating functions, running cosmological constants, integration functions, and effective matter sources. These constructions are further extended to quantum gravity (QG) models involving effective local Lorentz symmetry violations and anisotropic scaling, as realized in Hořva–Lifshitz (HL)-type theories. The classical geometric framework is formulated on Lorentz manifolds endowed with nonholonomic 2+2 and 3+1 splitting structures and subsequently generalized to quantum configurations determined by HL-type generating functions. The 2+2 dyadic splitting, incorporating connection distortions, provides a systematic method for constructing exact and parametric classical and quantum solutions described by generating functions and effective sources depending on all spacetime coordinates, physical constants, and anisotropic scaling or deformation parameters. The complementary 3+1 splitting allows for a consistent implementation of the BFV quantization procedure. We demonstrate the renormalizability of off-diagonal quantum HL-type deformations of GR. The resulting classical and quantum nonholonomic BFV models represent viable candidates for asymptotically free theories of gravity and may provide a mechanism for resolving unitarity issues in QG. In appropriate classical limits, the framework reproduces physically relevant off-diagonal GR solutions with or without locally anisotropic scaling, offering potential applications to nonlinear classical and quantum phenomena in accelerating cosmology and dark energy and dark matter physics
Dynamic two-level system in the presence of a delta-function pulse: Exactly solvable dynamic system
No full textThe Landau-Zener formula represents the only case where a dynamic quantum system was solved exactly analytically. There is no model of a system, which is perturbed by a temporal pulse, and can be solved exactly. It is suggested to use a delta-function perturbation, a model which has an exact analytical solution, to model the effect of a finite period pulse perturbation. Not only can this model be solved exactly and mimic the effect of a very narrow pulse, but it also presents a quantization rule for suppressed transmission (i.e., no change in initial state), which resembles qualitatively a similar quantization rule that appears due to the presence of a finite period pulse. Nevertheless, despite its simplicity, the model exhibits non-trivial dynamics that challenge approximation schemes. Specifically, it shows that the suppressed transmission criterion substantially changes due to an arbitrarily small change in potential value
Sibling sub-Neptunes around sibling M dwarfs: TOI-521 and TOI-912
No full textContext. Sub-Neptunes are absent in the Solar System, yet they are the most common category of planets found in our Galaxy. This kind of planet challenges the internal structure models, prompts investigations into its formation and evolution, and pushes atmospheric characterisation studies to break the degeneracy in their inner composition.
Aims. We report here the discovery and characterisation of new sub-Neptunes orbiting two similar M dwarfs, TOI-521 (Teff = 3544 ± 100 K, V = 14.7 mag) and TOI-912 (Teff = 3572 ± 100 K, V = 12.7 mag). Each star hosts a transiting planetary candidate identified by TESS and is part of the THIRSTE
Protein Folding: Recent Advances and Analysis in Computing
No full textProtein folding is a fundamental yet elusive problem: a protein's three-dimensional structure determines its function, but misfolding underlies disorders such as Alzheimer's. Experimental techniques like X-ray crystallography and NMR resolve structures but cannot keep pace with the explosive growth of sequence data. Consequently, computational approaches - from simplified hydrophobic-polar (HP) lattice models to deep neural networks - have become indispensable. This paper reviews recent advances in computational protein folding, using the HP model as a conceptual test bed. It surveys classic heuristics, modern deep reinforcement learning, variational generative techniques and emerging quantum algorithms for NP-hard lattice models, and compares them with breakthroughs in all-atom structure prediction exemplified by AlphaFold and RosettaFold. Benchmark datasets, evaluation metrics and ongoing challenges - such as data bias, dynamic folding and integration of physical constraints - are discussed. The review concludes that future progress will likely come from hybrid methods that combine machine-learning flexibility with physics-based priors, expanded and more diverse structural data sets, and algorithmic innovations, including quantum-inspired heuristics and efficient hardware. Such advances could enable more accurate folding predictions, facilitate rational drug design and deepen our understanding of protein misfolding diseases
Integrative Use of Pelvic Floor Muscle Training and Traditional Chinese Medicine Rehabilitation for Postpartum Pelvic Floor Dysfunction
No full textPelvic Floor Dysfunction (PFD) is highly prevalent in postpartum women, with 40%-91% of primiparas having symptoms within one year post-delivery. It is associated with urinary incontinence, pelvic organ prolapses, and psychosocial issues such as anxiety and depression, leading to considerable health and quality-of-life burdens. Pelvic floor muscle training is widely regarded as the first-line conservative intervention, as it strengthens pelvic support structures and improves continence. Nevertheless, its effectiveness is often constrained by poor adherence, limited supervision, and difficulty in sustaining long-term training intensity. Rehabilitation approaches within the framework of Traditional Chinese Medicine (TCM), such as acupuncture, tuina, and Baduanjin exercise, have been reported to improve local blood perfusion, regulate neuromuscular pathways, and relieve pelvic discomfort, although high-quality evidence and standardized protocols remain insufficient. Emerging studies indicate that combining pelvic floor muscle training with TCM rehabilitation achieves greater reductions in urine leakage, better continence-related quality-of-life scores, and shorter recovery time compared with either approach alone. This review aims to evaluate the combined effects and synergistic mechanisms of pelvic floor muscle training and TCM rehabilitation in postpartum pelvic floor dysfunction, thereby informing future clinical strategies
Association between Periodontitis and Systemic Diseases
No full textPeriodontal disease is a chronic inflammatory disease that affects the gums and periodontal tissues. It is one of the main causes of tooth loss in adults, affecting more than half of the world's adults to varying degrees, and has become a major public health issue. Increasing evidence suggests that periodontal disease is closely linked to systemic health. Pathogenic bacteria and their toxins can enter the bloodstream, it induces a low-grade inflammatory state, leading to the occurrence and development of various systemic diseases. For instance, in cardiovascular health, periodontal inflammation may damage endothelial function and promote atherosclerosis. In metabolic regulation, proinflammatory mediators impair insulin signalling, thereby worsening glycemic control in diabetes. In pregnancy, microbial invasion and inflammatory mediators may disrupt placental function, increased risk of preterm birth and low birth weight. Although conventional periodontal therapy can improve local outcomes, it may not completely alleviate systemic effects. This review aims to summarize the recent evidence on the link between periodontal disease and systemic health, focusing on mechanisms and potential strategies for prevention and clinical management
Resonance with quasinormal modes in long-range kinks’ collisions
No full textWe consider a rational scalar field model in (1+1)-dimensions where the long-range character of the kinks is controllable. We show via numerical simulations that kinks with long-range tails on both sides can exhibit resonance windows. The resonant energy exchange mechanism occurs via the excitation of quasinormal modes, which we obtain via a spectral analysis. Additionally, we locate a resonance window in a family of models with long-range tails on both sides. Moreover, we propose a new algorithm for initializing long-range kink collisions, based on convection–diffusion dynamics
CRISPR-Cas Technology for Constructing Engineered Strains to Produce High Value-Added Industrial Products
No full textWith its ability to make precise, effective, and programmable genetic changes, the CRISPR-Cas system has become a revolutionary tool for microbial genome engineering. This article summarizes the use of CRISPR-Cas technology to create modified strains for the manufacturing of high value-added industrial products. First, the basic mechanisms of CRISPR-Cas systems are explained, including target recognition, Cas-mediated DNA cleavage, and repair pathways including HDR and NHEJ. This article then discusses representative applications in three key microbial hosts: Bacillus subtilis, Saccharomyces cerevisiae, and Escherichia coli. In B. subtilis, CRISPR-based systems enable multiplex and iterative editing for optimizing hyaluronic acid biosynthesis; in S. cerevisiae, they facilitate marker-free and multi-copy integration for high-value metabolite production; and in E. coli, they improve pathway balance and editing precision for fine chemical synthesis. Collectively, these advances illustrate how CRISPR-Cas technologies provide a versatile and universal platform for rational strain design. The integration of CRISPR-based editing with metabolic engineering continues to drive sustainable, efficient, and scalable biomanufacturing of high value-added products across diverse microbial systems
Phytotherapeutics for parasite control in global fish aquaculture: a review of anti-monogenean agents and their mechanisms
No full textWith the intensification of fish cultivation, also increased threat of parasitic diseases to fish health, growth, production, and productivity. This has had huge negative impacts and necessitate alternative therapeutics for the control and treatment of diseases. Medicinal plants have been integral to human life, utilized as a natural source of bioactive compounds for use in veterinary and human medicine. These plants produce diverse chemical compounds, such as alkaloids, saponins, phenolic compounds, tannins, terpenoids, steroids, flavonoids, and essential oils, which have been used in fish aquaculture. Thus, the present study aimed to synthesize papers published within the last eight years on the efficacy of different extracts, essential oils, and bioactive compounds derived from medicinal plants, as well as their potential modes of action on fish parasites, with an emphasis on fish parasitic monopisthocotylans and polyopisthocotylans (formerly monogeneans). Data on phytotherapeutic products, phytochemicals, targeted parasites, and in vitro and in vivo experiment outcomes were extracted from the literature and summarized. Additionally, the mechanisms by which these phytotherapics act on parasites were shown and discussed. The bioactivity of essential oils and crude herbal extracts in controlling and eliminating parasites is directly linked to the action of their major components, which demonstrate parasiticidal and anti-monopisthocotylans and polyopisthocotylans activity, even when isolated. This provides a wide range of options. Phytotherapeutic agents are an alternative to chemotherapeutic agents because they pose no risk of acute or chronic toxicity to host fish, nor do they contaminate handlers. They also do not cause parasitic resistance and are environmentally friendly. Therefore, they are recommended for use in management strategies to control and treat parasite infections in fish aquaculture due to their anthelmintic and parasiticide properties. Lastly, although the economic and aquaculture viability of phytotherapeutic agents is unknown, the environmental benefits are evident compared to the widespread use of chemotherapeutics
Synthesis of Mo-doped SnO
No full textIn this work, Sn1-xMoxO2 (x = 0.00, 0.01, 0.02, 0.04) nanoparticles powders were produced successfully at room temperature using the co-precipitation method. These types of nanoparticles are widely used as a dopant for photo anodes due to its thermal stability and unique electronic configuration, it exhibits different oxidation states. The structural and optical characterization of the nano-powders were investigated by DRX, FTIR, and UV-Visible spectroscopy techniques. The DRX measurements showed that all samples had a tetragonal rutile structure of polycrystalline SnO2 and the (110) preferential orientation of the undoped sample remains with 1%, 2% and 4% Mo doped SnO2 samples. Also, the grain size and the micro-deformation are calculated by Williamson-Hall and Debye-Scherrer formulas, the grain size is approximately between 8nm and 10nm. The presence of a band at 632 cm-1 in the FTIR spectrum confirms the existence of the O-Sn-O bond