Constructing G2 Continuous Curve on Freeform Surface with Normal Projection

AbstractThis article presents a new method for G2 continuous interpolation of an arbitrary sequence of points on an implicit or parametric surface with prescribed tangent direction and curvature vector, respectively, at every point. First, a G2 continuous curve is constructed in three-dimensional space. Then the curve is projected normally onto the given surface. The desired interpolation curve is just the projection curve, which can be obtained by numerically solving the initial- value problems for a system of first-order ordinary differential equations in the parametric domain for parametric case or in three-dimensional space for implicit case. Several shape parameters are introduced into the resulting curve, which can be used in subsequent interactive modification so that the shape of the resulting curve meets our demand. The presented method is independent of the geometry and parameterization of the base surface. Numerical experiments demonstrate that it is effective and potentially useful in numerical control (NC) machining, path planning for robotic fibre placement, patterns design on surface and other industrial and research fields

FABRICATION OF CRYSTALLINE COLLOIDAL ARRAY PHOTONIC CRYSTALS AND APPLICATIONS

Crystalline colloidal array (CCA) photonic crystals (PCs) are periodic structures formed by the self-assembly of monodisperse, highly-charged particles in low ionic strength aqueous solutions. Similar to an atomic crystal but with much larger lattice spacings, the CCA can efficiently diffract light in the UV, visible and near-IR spectral regions. This thesis reports the development of new CCA materials, novel CCA Bragg diffraction devices, and utilization of CCA PC templates for new nanostructure and nanomaterial fabrication. We use CCA for development of a CCA deep UV narrow band filter that acts as a Rayleigh rejection filter for UV Raman spectroscopy and for templates for solid-state UV Raman cross section determinations. We developed novel CCA PC deep UV Bragg diffraction devices. We synthesized small, monodisperse, highly surface-charged silica particles and prepared novel silica CCA through the self-assembly of these particles. The silica CCA efficiently Bragg diffract light in the deep UV. The diffracted wavelength was varied by tilting the CCA orientation to the incident beam. We demonstrated the utility of the silica CCA filter as a Rayleigh rejection filter in Teflon UV Raman measurements. We conducted the first resonance Raman cross-section measurements of solids that avoids self-absorption bias by using PC templates. We fabricated complex stoichiometrically defined nanoparticles (NaNO3/Na2SO4 nanoparticles) by utilizing the defined interstitial volume of close-packed PCs. We successfully determined the solid-state NaNO3 UV resonance Raman cross-sections by using solid Na2SO4 as an internal standard. We also developed a refractive-index matching method to measure solid-state Na2SO4 UV Raman cross sections that avoids the effect of the local field and avoids interface scattering of the incident light. We developed a facile method to fabricate silica shell PCs through the use of flexible poly(N-isopropylacrylamide) (PNIPAm) core templates. We synthesized monodisperse PNIPAm-silica core-shell particles and demonstrated their reversible swelling and shrinking as the temperature is cycled. We fabricated close-packed PCs of PNIPAm-silica core-shell particles and further fabricated hollow silica shell PCs by removing the PNIPAm cores by calcination

Advances in Organic Small Molecule-Based Fluorescent Probes for Precision Detection of Liver Diseases:A Perspective on Emerging Trends and Challenges

Liver disease poses a significant challenge to global health, and its early diagnosis is crucial for improving treatment outcomes and patient prognosis. Since fluctuation of key biomarkers during the onset and progression of liver diseases can directly reflect liver health and normal/abnormal function, biomarker-based assays are vital tools for the early detection of liver disease. In this context, small molecule fluorescent probes have undeniably emerged as indispensable tools for diagnosis and analysis, with an ever-growing number of small molecule-based fluorescent probes being developed over recent years, with the sole aim of monitoring relevant biomarkers of liver disease. This perspective will focus on the development and application of probes developed primarily over the last 10 years for diagnosing a range liver disease-related processes. It will outline the foundational design strategies for developing promising probes, their optical response to key biomarkers, and how they have been demonstrated in proof-of-concept imaging applications. Current challenges and new developments in the field will be discussed, with the aim of providing insights and highlighting opportunities in the field.</p

Versatile Ratiometric Fluorescent Probe Based on the Two-Isophorone Fluorophore for Sensing Nitroxyl

Nitroxyl (HNO) is closely linked with numerous biological processes. Fluorescent probes provide a visual tool for determining HNO. Due to fluorescence quenching by HNO-responsive recognition groups, most of the current fluorescent probes exhibit an "off-on"fluorescence response. As such, the single fluorescence signal of these probes is easily affected by external factors such as the microenvironment, sensor concentration, and photobleaching. Herein, we have developed a ratiometric fluorescent probe (CHT-P) based on our previously developed two-isophorone fluorophore. CHT-P could be used to determine HNO through ratiometric signal readouts with high selectivity and sensitivity, ensuring the accurate quantitative detection of HNO. Additionally, the probe exhibited low cytotoxicity, was cell permeable, and could be used for ratiometric imaging of HNO in cells. Finally, CHT-P-coated portable test strips were used to determine HNO using the solid-state fluorescence signal readout. </p

Effect of tongue temperature on oral tactile sensitivity and viscosity discrimination

© 2019 Elsevier Ltd An Individual's oral capability in perceiving food texture influences greatly food appreciation and preference. While there is no doubt that one's ability of texture discrimination depends on various oral physiological characteristics of the individual, it is not yet clear how tongue surface temperature affects the sensitivity of texture discrimination. This study was designed to test the effects of tongue surface temperature on oral tactile sensitivity and viscosity discrimination. A total of twenty healthy subjects (ten females and ten males; mean age: 25 ± 1 yrs, mean body mass index: 20.5 ± 2.9 kg/m2) participated in this study. Water at different temperatures (0, 20, 37, and 45 °C) and capsaicin solutions (5,10, and 20 ppm) were used as physical and chemical stimulations to alter tongue temperature, respectively. Semmes-Weinstein monofilaments, Bio-Thesiometer, and Touch-Test®Two-point discriminator were respectively applied to assess the tongue's sensitivity of light touch, vibratory perception and two-point discrimination before and after treatment with both physical and chemical stimuli. Maltodextrin solutions were used for oral viscosity discrimination. Tongue's vibratory perception thresholds varied significantly (P < 0.01), indicating an increase of 0.6 × 10−6cm in vibratory perception threshold when tongue surface temperature decreased from 33 °C to 20 °C, while light touch and two-point discrimination thresholds remained unchanged. The application of capsaicin (5, 10, and 20 ppm) produced an increase in tongue surface temperature but did not affect oral tactile sensitivity. Viscosity discrimination increased both after rinsing the mouth with warm water and capsaicin application (20 ppm). Capsaicin (20 ppm) increased tongue temperature by 1.3 °C and lead to a decrease in viscosity discrimination threshold from 34.7% to 20.2%. After stimulation with water at 37 °C and 45 °C, the tongue temperature increased by 3 °C (from 34.2 °C to 37.2 °C), while threshold of viscosity discrimination decreased from 28.1% to 23.1%. When water was used to change tongue surface temperature, a positive correlation was found between vibratory perception sensitivity and viscosity discrimination ability, suggesting the capacity of discriminating viscosity might depend on vibratory perception sensitivity

Fluorescent small molecule donors

Small molecule donors (SMDs) play subtle roles in the signaling mechanism and disease treatments. While many excellent SMDs have been developed, dosage control, targeted delivery, spatiotemporal feedback, as well as the efficiency evaluation of small molecules are still key challenges. Accordingly, fluorescent small molecule donors (FSMDs) have emerged to meet these challenges. FSMDs enable controllable release and non-invasive real-time monitoring, providing significant advantages for drug development and clinical diagnosis. Integration of FSMDs with chemotherapeutic, photodynamic or photothermal properties can take full advantage of each mode to enhance therapeutic efficacy. Given the remarkable properties and the thriving development of FSMDs, we believe a review is needed to summarize the design, triggering strategies and tracking mechanisms of FSMDs. With this review, we compiled FSMDs for most small molecules (nitric oxide, carbon monoxide, hydrogen sulfide, sulfur dioxide, reactive oxygen species and formaldehyde), and discuss recent progress concerning their molecular design, structural classification, mechanisms of generation, triggered release, structure–activity relationships, and the fluorescence response mechanism. Firstly, from the large number of fluorescent small molecular donors available, we have organized the common structures for producing different types of small molecules, providing a general strategy for the development of FSMDs. Secondly, we have classified FSMDs in terms of the respective donor types and fluorophore structures. Thirdly, we discuss the mechanisms and factors associated with the controlled release of small molecules and the regulation of the fluorescence responses, from which universal guidelines for optical properties and structure rearrangement were established, mainly involving light-controlled, enzyme-activated, reactive oxygen species-triggered, biothiol-triggered, single-electron reduction, click chemistry, and other triggering mechanisms. Fourthly, representative applications of FSMDs for trackable release, and evaluation monitoring, as well as for visible in vivo treatment are outlined, to illustrate the potential of FSMDs in drug screening and precision medicine. Finally, we discuss the opportunities and remaining challenges for the development of FSMDs for practical and clinical applications, which we anticipate will stimulate the attention of researchers in the diverse fields of chemistry, pharmacology, chemical biology and clinical chemistry. With this review, we hope to impart new understanding thereby enabling the rapid development of the next generation of FSMDs

Fluorescent Probes for Disease Diagnosis

The identification and detection of disease-related biomarkers is essential for early clinical diagnosis, evaluating disease progression, and for the development of therapeutics. Possessing the advantages of high sensitivity and selectivity, fluorescent probes have become effective tools for monitoring disease-related active molecules at the cellular level and in vivo. In this review, we describe current fluorescent probes designed for the detection and quantification of key bioactive molecules associated with common diseases, such as organ damage, inflammation, cancers, cardiovascular diseases, and brain disorders. We emphasize the strategies behind the design of fluorescent probes capable of disease biomarker detection and diagnosis and cover some aspects of combined diagnostic/therapeutic strategies based on regulating disease-related molecules. This review concludes with a discussion of the challenges and outlook for fluorescent probes, highlighting future avenues of research that should enable these probes to achieve accurate detection and identification of disease-related biomarkers for biomedical research and clinical applications

Dual-Responsive Fluorescent Probes:Advances in Biosensing, Diagnosis and Therapy

Recent years have witnessed rapid developments in molecular imaging for fundamental biomedical research and clinical diagnostics. Particularly, fluorescence imaging represents an indispensable technique, enabling longitudinal monitoring of intravital physiopathological activities in a real-time and non-invasive manner. Dual-responsive fluorescent probes, which circumvent non-specific signal activation and background noise, have exhibited remarkably enhanced selectivity, high spatiotemporal resolution, and multiplexing capability. With the increasing prevalence of precision medicine, dual-responsive fluorescent probes offer promising opportunities to enhance diagnostic accuracy and optimize therapeutic efficacy. In this review, the design strategies for customized dual-responsive fluorescent probes are comprehensively summarized. Subsequently, representative examples in biosensing, diagnosis, and therapy are highlighted. Finally, the review provides perspectives and discusses key challenges in advancing dual-responsive fluorescent probes toward clinical biomedical applications.</p

The role of N6-methyladenosine (m6A) in kidney diseases

Chemical modifications are a specific and efficient way to regulate the function of biological macromolecules. Among them, RNA molecules exhibit a variety of modifications that play important regulatory roles in various biological processes. More than 170 modifications have been identified in RNA molecules, among which the most common internal modifications include N6-methyladenine (m6A), n1-methyladenosine (m1A), 5-methylcytosine (m5C), and 7-methylguanine nucleotide (m7G). The most widely affected RNA modification is m6A, whose writers, readers, and erasers all have regulatory effects on RNA localization, splicing, translation, and degradation. These functions, in turn, affect RNA functionality and disease development. RNA modifications, especially m6A, play a unique role in renal cell carcinoma disease. In this manuscript, we will focus on the biological roles of m6A in renal diseases such as acute kidney injury, chronic kidney disease, lupus nephritis, diabetic kidney disease, and renal cancer

Comparative analysis of blood whole transcriptome profiles in Yili horses pre- and post-5000-meter racing

This study employed Yili horses participating in a 5000-meter race as a model to investigate exercise-induced gene expression alterations in peripheral blood using whole transcriptome sequencing. Jugular vein blood samples from the three leading horses were collected pre- and immediately post-race, yielding 2,171 differentially expressed mRNAs (2,080 upregulated, 91 downregulated), 4,375 differentially expressed LncRNAs (4,354 upregulated), and 68 differentially expressed circRNAs (64 upregulated). GO/KEGG analyses demonstrated significant enrichment of differential mRNAs in transmembrane transport function and pivotal signaling pathways (cAMP, MAPK, PI3K-Akt). Differential lncRNAs targeted neuro-signaling pathways (e.g., Neuroactive ligand-receptor interaction, Calcium signaling) and developmental regulators (stem cell pluripotency). Source genes of circRNAs were enriched in axon guidance and immune-related T cell receptor signaling. Molecular functions converged on transporter/receptor activity (mRNA/lncRNA) and nucleic acid/GTP binding (circRNA source genes). The protein-protein interaction analysis identified ten central genes within the heat shock protein family, such as HSP90AA1 and HSPA4. Notably, significant upregulation of HCN4, IGF1, PTHR1, and FGF23 indicated their potential roles in modulating cardiac rhythm, promoting tissue repair, and maintaining calcium-phosphorus homeostasis during exercise adaptation. This study provides comprehensive overview of transcriptomic regulatory mechanisms in the blood of Yili horses, offering a molecular framework for advancing understanding of physiological adaptation to exercise and optimizing equine exercise protocols