ABSTRACT
Viral infections usually induce the rearrangement of cellular cytoskeletal proteins and organelle membrane structures, thus creating independent compartments [termed replication organelles (ROs)] to facilitate viral genome replication. Within the ROs, viral replicases, including polymerases, helicases, and ligases, play functional roles during viral replication. These viral replicases are pivotal in the virus life cycle, and numerous studies have demonstrated that the viral replicases could be the potential targets for drugs development. Here, we summarize primarily the key replicases within viral ROs and emphasize the advancements of antiviral drugs targeting crucial viral replicases, providing novel insights into the future development of antiviral strategies.
ABSTRACT
Nanozymes are promising antimicrobials, as they produce reactive oxygen species (ROS). However, the intrinsic lack of selectivity of ROS in distinguishing normal flora from pathogenic bacteria deprives nanozymes of the necessary selectivities of ideal antimicrobials. Herein, we exploit the physiological conditions of bacteria (high alkaline phosphatase (ALP) expression) using a novel CuO nanoparticle (NP) nanoenzyme system to initiate an ALP-activated ROS prodrug system for use in the on-demand precision killing of bacteria. The prodrug strategy involves using 2-phospho-L-ascorbic acid trisodium salt (AAP) that catalyzes the ALP in pathogenic bacteria to generate ascorbic acid (AA), which is converted by the CuO NPs, with intrinsic ascorbate oxidase- and peroxidase-like activities, to produce ROS. Notably, the prodrug system selectively kills Escherichia coli (pathogenic bacteria), with minimal influence on Staphylococcus hominis (non-pathogenic bacteria) due to their different levels of ALP expression. Compared to the CuO NPs/AA system, which generally depletes ROS during storage, CuO NPs/AAP exhibits a significantly higher stability without affecting its antibacterial activity. Furthermore, a rat model is used to indicate the applicability of the CuO NPs/AAP fibrin gel in wound disinfection in vivo with negligible side effects. This study reveals the therapeutic precision of this bifunctional tandem nanozyme platform against pathogenic bacteria in ALP-activated conditions.
Subject(s)
Alkaline Phosphatase , Anti-Bacterial Agents , Copper , Disinfection , Escherichia coli , Prodrugs , Reactive Oxygen Species , Copper/chemistry , Copper/pharmacology , Animals , Prodrugs/pharmacology , Prodrugs/chemistry , Alkaline Phosphatase/metabolism , Rats , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Escherichia coli/drug effects , Reactive Oxygen Species/metabolism , Disinfection/methods , Ascorbic Acid/pharmacology , Ascorbic Acid/chemistry , Ascorbic Acid/analogs & derivatives , Metal Nanoparticles/chemistry , Rats, Sprague-Dawley , MaleABSTRACT
ABSTRACT: Aneurysms are localized dilations of blood vessels, which can expand to 50% of the original diameter. They are more common in cardiovascular and cerebrovascular vessels. Rupture is one of the most dangerous complications. The pathophysiology of aneurysms is complex and diverse, often associated with progressive vessel wall dysfunction resulting from vascular smooth muscle cell death and abnormal extracellular matrix synthesis and degradation. Multiple studies have shown that long noncoding RNAs (lncRNAs) play a significant role in the progression of cardiovascular and cerebrovascular diseases. Therefore, it is necessary to find and summarize them. LncRNAs control gene expression and disease progression by regulating target mRNA or miRNA and are biomarkers for the diagnosis and prognosis of aneurysmal cardiovascular and cerebrovascular diseases. This review explores the role, mechanism, and clinical value of lncRNAs in aneurysms, providing new insights for a deeper understanding of the pathogenesis of cardiovascular and cerebrovascular aneurysms.
Subject(s)
Intracranial Aneurysm , Muscle, Smooth, Vascular , Myocytes, Smooth Muscle , Phenotype , RNA, Long Noncoding , Humans , Muscle, Smooth, Vascular/pathology , Muscle, Smooth, Vascular/metabolism , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , Intracranial Aneurysm/genetics , Intracranial Aneurysm/pathology , Intracranial Aneurysm/metabolism , Intracranial Aneurysm/physiopathology , Myocytes, Smooth Muscle/metabolism , Myocytes, Smooth Muscle/pathology , Animals , Gene Expression Regulation , Aneurysm/genetics , Aneurysm/pathology , Aneurysm/metabolism , Cardiovascular Diseases/genetics , Cardiovascular Diseases/pathology , Cardiovascular Diseases/metabolism , Cardiovascular Diseases/physiopathology , Signal TransductionABSTRACT
Developing sensor arrays capturing comprehensive fluorescence (FL) spectra from a single probe is crucial for understanding sugar structures with very high similarity in biofluids. Therefore, the analysis of highly similar sugar' structures in biofluids based on the entire FL of a single nanozyme probe needs more concern, which makes the development of novel alternative approaches highly wanted for biomedical and other applications. Herein, a well-designed deep learning model with intrinsic information of 3D FL of CuO nanoparticles (NPs)' oxidase-like activity was developed to classify and predict the concentration of a group of sugars with very similar chemical structures in different media. The findings presented that the overall accuracy of the developed model in classifying the nine selected sugars was (99-100 %), which prompted us to transfer the developed model to predict the concentration of the selected sugars at a concentration range of (1-100 µM). The transferred model also gave excellent results (R2 = 97-100 %). Therefore, the model was extended to other more complex applications, namely the identification of mixtures of sugars in serum and the detection of polysaccharides in different media such as serum and lake water. Notably, LOD for fructose was determined at 4.23 nM, marking a 120-fold decrease compared to previous studies. Our developed model was also compared with other deep learning-based models, and the results have demonstrated remarkable progress. Moreover, the identification of other possible coexisting interference substances in lake water samples was considered. This work marks a significant advancement, opening avenues for the widespread application of sensor arrays integrating nanozymes and deep learning techniques in biomedical and other diverse fields.
ABSTRACT
The kagome spin ice can host frustrated magnetic excitations by flipping its local spin. Under an inelastic tunneling condition, the tip in a scanning tunneling microscope can flip the local spin, and we apply this technique to kagome metal HoAgGe with a long-range ordered spin ice ground state. Away from defects, we discover a pair of pronounced dips in the local tunneling spectrum at symmetrical bias voltages with negative intensity values, serving as a striking inelastic tunneling signal. This signal disappears above the spin ice formation temperature and has a dependence on the magnetic fields, demonstrating its intimate relation with the spin ice magnetism. We provide a two-level spin-flip model to explain the tunneling dips considering the spin ice magnetism under spin-orbit coupling. Our results uncover a local emergent excitation of spin ice magnetism in a kagome metal, suggesting that local electrical field induced spin flip climbs over a barrier caused by spin-orbital locking.
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Pseudolaric Acid B (PAB), a natural product with remarkable anti-tumor activity, is a starting point for new anticancer therapeutics. We designed and synthesized 27 PAB derivatives and evaluated their anti-proliferative activities against four cancer cell lines: MCF-7, HCT-116, HepG2, and A549. Compared with unmodified PAB, the PAB derivatives showed stronger anti-proliferative activity. The ability of compound D3 (IC50 = 0.21 µM) to inhibit HCT-116 cells was approximately 5.3 times that of PAB (IC50 = 1.11 µM) and the antiproliferative action was unrelated to cytotoxicity (SI=20.38), indicating its superior safety profile (PAB; SI=0.95). Compound D3 effectively suppressed the EdU-positive rate and reduced colony formation, arrested HCT-116 cells in the S and G2/M phases and induced apoptosis. In vivo experiments further demonstrated low toxicity of compound D3 while suppressing tumor growth in mice. In summary, given its strong anti-proliferative effect and relative safety, further development of compound D3 is warranted.
ABSTRACT
A BPAPTPyC organic molecule containing a sandwich structural chromophore is designed and synthesized to produce blue thermally activated delayed fluorescence (TADF). The chromophore is composed of two di(4-tert-butylphenyl)amino donors and one inserted terpyridyl acceptor hitched at positions 1, 8, and 9 of a single carbazole via the p-phenylene group, in which the multiple space π-π interactions between the donor and acceptor enable the molecule to possess the TADF feature with a high energy emission at 470 nm but a low photoluminescence quantum yield (PLQY) and a small proportion of the delayed component. In contrast, the corresponding Zn(BPAPTPyC)Cl2 complex has a high PLQY and a short lifetime with a red-shifted emission due to the enhanced rigidity and electron accepting ability of the terpyridyl group from coordination. A solution-processed organic light-emitting diode (OLED) based on the complex achieves a maximum external quantum efficiency (EQE) of 17.9% with an emission peak at 585 nm, while an OLED of the organic molecule produces blue emission with a maximum EQE of 2.7%.
ABSTRACT
Aim: Nano-hydroxyapatite (nHA) is a good nanocarrier to load 223Ra, but the low specific activity (sp.act.) of 223Ra@nHA limits its application in medicine. Methods: We proposed a method for preparing nHA using PEG as a template, which significantly increases the sp.act of 223Ra@nHA and a new method to loaded 99mTc for in vivo tracking. Results: The nHA synthesized using PEG as a template was associated with higher sp.act for 223Ra in comparison to nHA with identical particle size and without PEG. The nHA load 99mTc-MDP was associated with higher labeling rate and stability in comparison to 99mTc. Conclusion: All these findings suggest that using PEG as a template and 99mTc-MDP could be the most effective of synthetic 223Ra/99mTc@nHA.
[Box: see text].
Subject(s)
Bone Neoplasms , Durapatite , Particle Size , Radium , Durapatite/chemistry , Humans , Bone Neoplasms/drug therapy , Bone Neoplasms/diagnostic imaging , Radium/chemistry , Polyethylene Glycols/chemistry , Nanoparticles/chemistry , Technetium/chemistry , Cell Line, Tumor , Radiopharmaceuticals/chemistry , Animals , Technetium Tc 99m Medronate/chemistryABSTRACT
The B169L protein (pB169L) of African swine fever virus (ASFV) is a structural protein with an unidentified function during the virus replication. The sequences of the B169L gene and the downstream B438L gene are separated by short intergenic regions. However, the regulatory mode of the gene transcription remains unknown. Here, we identified two distinct promoter regions and two transcription start sites (TSSs) located upstream of the open reading frame (ORF) of B438L. Using the promoter reporter system, we demonstrated that the cis activity of the ORF proximal promoter exhibited significantly higher levels compared with that of the distal promoter located in the B169L gene. Furthermore, transfection with the plasmids with two different promoters for B438L could initiate the transcription and expression of the B438L gene in HEK293T cells, and the cis activity of the ORF proximal promoter also displayed higher activities compared with the distal promoter. Interestingly, the B438L distal promoter also initiated the transcription of the alternatively spliced B169L mRNA (B169L mRNA2) encoding a truncated pB169L (tpB169L) (amino acids 92-169), and the gene transcription efficiency was increased upon mutation of the initiation codon located upstream of the alternatively spliced B169L gene. Taken together, we demonstrated that the distal promoter of B438L gene initiates the transcription of both the B438L mRNA and B169L mRNA2. Comprehensive analysis of the transcriptional regulatory mode of the B438L gene is beneficial for the understanding of the association of B438L protein and pB169L and the construction of the gene-deleted ASFV.
Subject(s)
African Swine Fever Virus , Alternative Splicing , Gene Expression Regulation, Viral , Promoter Regions, Genetic , Transcription Initiation Site , Transcription, Genetic , African Swine Fever Virus/genetics , Animals , Humans , Swine , HEK293 Cells , Viral Proteins/genetics , Viral Proteins/metabolism , African Swine Fever/virology , Virus ReplicationABSTRACT
BACKGROUND: Surprisingly, despite the high prevalence of metformin use in type 2 diabetes (T2D) patients with heart disease, limited safety data is available regarding metformin use in patients with acute and critical heart disease. METHODS: In this single-center retrospective study, patients admitted to the cardiology department for heart failure (HF) or acute coronary syndrome (ACS) between December 2013 and December 2021 and who underwent arterial blood gas analysis at admission with an estimated glomerular clearance rate of ≥45 ml/min/1.73 m2 were identified. The incidences of hyperlactatemia, acidosis, and 30-day in-hospital mortality were compared between preadmission metformin users and nonusers. RESULTS: Of 526 admissions, 193/193 metformin users/nonusers were selected in a propensity score-matched model. Metformin users had greater lactate levels (2.55 ± 2.07 mmol/l vs. 2.00 ± 1.80 mmol/l P < 0.01), a greater incidence of hyperlactatemia [odds ratio (OR) = 2.55; 95% confidence interval (CI), 1.63-3.98; P < 0.01] and acidosis (OR = 1.78; 95% CI, 1.00-3.16; P < 0.05) at admission and a greater incidence of in-hospital mortality (OR = 3.83; 95% CI, 1.05-13.94; P < 0.05), especially those with HF/acute myocardial infarction, elderly age, or without preadmission insulin use. CONCLUSIONS: Our results suggest that, compared to metformin nonusers, preadmission use of metformin may be associated with a greater incidence of hyperlactatemia and acidosis at admission and greater 30-day in-hospital mortality among T2D patients with HF or ACS at high risk of hypoxia, particularly those without preadmission insulin use. The safety of metformin in this population needs to be confirmed in prospective controlled trials.
Subject(s)
Diabetes Mellitus, Type 2 , Hospital Mortality , Hyperlactatemia , Hypoglycemic Agents , Metformin , Humans , Metformin/therapeutic use , Metformin/adverse effects , Male , Female , Hospital Mortality/trends , Retrospective Studies , Aged , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/mortality , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/epidemiology , Hyperlactatemia/epidemiology , Hyperlactatemia/blood , Hyperlactatemia/chemically induced , Incidence , Hypoglycemic Agents/therapeutic use , Hypoglycemic Agents/adverse effects , Middle Aged , Hypoxia/epidemiology , Hypoxia/mortality , Hypoxia/blood , Patient Admission/trends , Heart Diseases/epidemiology , Heart Diseases/mortality , Heart Diseases/blood , Aged, 80 and over , Risk FactorsABSTRACT
Archwire bending is the key to orthodontic treatment, and multi-time bendings are inevitable during manual and robotic automated bending. The purpose of this paper is to quantitatively evaluate the mechanical effects of the different preparation modes and to compare the mechanical properties of the orthodontic loops in one and multiple bends. Three types of typical stainless steel orthodontic loops (vertical loop, T-loop, and L-loop) were used to quantify the mechanical effect of patterns for preparation by experimental comparison between loops with different bending times by using an orthodontic force tester (OFT). The results were statistically analyzed by t-test. The fracture test of the stainless steel archwire was also carried out, and the bending times at fracture were recorded. Results of the tests indicate that one-time and multi-time bending have a significant mechanical effect on orthodontic appliances. Multi-time bending causes significant mechanical decreases and can damage the appliances.
ABSTRACT
Multiscale design of catalyst layers (CLs) is important to advancing hydrogen electrochemical conversion devices toward commercialized deployment, which has nevertheless been greatly hampered by the complex interplay among multiscale CL components, high synthesis cost and vast design space. We lack rational design and optimization techniques that can accurately reflect the nanostructure-performance relationship and cost-effectively search the design space. Here, we fill this gap with a deep generative artificial intelligence (AI) framework, GLIDER, that integrates recent generative AI, data-driven surrogate techniques and collective intelligence to efficiently search the optimal CL nanostructures driven by their electrochemical performance. GLIDER achieves realistic multiscale CL digital generation by leveraging the dimensionality-reduction ability of quantized vector-variational autoencoder. The powerful generative capability of GLIDER allows the efficient search of the optimal design parameters for the Pt-carbon-ionomer nanostructures of CLs. We also demonstrate that GLIDER is transferable to other fuel cell electrode microstructure generation, e.g., fibrous gas diffusion layers and solid oxide fuel cell anode. GLIDER is of potential as a digital tool for the design and optimization of broad electrochemical energy devices.
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Few clinical decision rules have been used to guide clinical management and predict outcomes in patients with pericardial tamponade. The objectives of this study are to identify the echocardiographic features associated with adverse outcomes in patients with pericardial effusions requiring pericardiocentesis and to apply a previously described four-point clinical and echocardiographic score to predict clinical outcomes over 24-hr, 30-day, and 1-year intervals. We performed a retrospective cohort review of patients who had transthoracic echocardiogram (TTE) performed and underwent pericardiocentesis within 48 h of emergency department presentation at two large tertiary care institutions. We constructed different stepwise logistic regression models and examined the associations of TTE characteristics and clinical features with ICU admission, hospital length of stay (h-LOS), and survival. The data set was then employed against a previously proposed scoring system to predict factors associated with clinical outcomes over 24 hr, 30 days, and 1 year. Two hundred thirty-nine patients were included in the final analysis. Echocardiographic characteristics of patients with pericardial tamponade who underwent pericardiocentesis are as follows: 69.1% right ventricular (RV) diastolic collapse, 62.3% exaggerated mitral valve (MV) inflow velocities, 56.4% inferior vena cava (IVC) plethora, and 53.4% right atrial (RA) systolic collapse. Increase in systolic blood pressure and increased variation in MV inflow velocity were associated with reduced ICU admission [OR: 0.94 (CI 0.90, 0.99), 0.28 (CI 0.09, 0.89), respectively]. In addition, a history of malignancy increased the length of hospital stay by about 3.89 days (CI 1.43-6.35, p < 0.01) and prior pericardiocentesis history was associated with 4.82-day increase in hospital stay (CI 1.19-8.45, p = 0.01). In utilizing the previously published prediction score, we found no statistically significant correlation in predicting survival. RV diastolic collapse and exaggerated MV inflow velocity were the most common echocardiographic findings in patients requiring pericardiocentesis. Contrary to prior studies, exaggerated MV inflow velocity was associated with reduced ICU admission. In addition, a previously described prediction score did not correlate with decreased survival in this cohort.
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Fast and high-fidelity qubit initialization is crucial for low-frequency qubits such as fluxonium, and in applications of many quantum algorithms and quantum error correction codes. In a circuit quantum electrodynamics system, the initialization is typically achieved by transferring the state between the qubit and a short-lived cavity through microwave driving, also known as the sideband cooling process in atomic system. Constrained by the selection rules from the parity symmetry of the wave functions, the sideband transitions are only enabled by multiphoton processes which require multitone or strong driving. Leveraging the flux tunability of fluxonium, we circumvent this limitation by breaking flux symmetry to enable an interaction between a noncomputational qubit transition and the cavity excitation. With single-tone sideband driving, we realize qubit initialization with a fidelity exceeding 99% within a duration of 300 ns, robust against the variation of control parameters. Furthermore, we show that our initialization scheme has a built-in benefit in simultaneously removing the second-excited state population of the qubit, and can be easily incorporated into a large-scale fluxonium processor.
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BACKGROUND: Obesity-associated male infertility is a common complication of obesity and has been increasing in prevalence. Blautia wexlerae has modulation effects on obesity. However, the action of B. wexlerae on obesity-associated male infertility is unclear. The nod-like receptor protein 3 (NLRP3) inflammasome has become a major target for addressing many diseases, including obesity-associated male infertility. This study aims to investigate the action of B. wexlerae on obesity-associated male infertility and the influence of B. wexlerae on NLRP3 inflammasome. MATERIALS AND METHODS: The fecal samples were collected from 60 infertile men with or without obesity and 30 healthy men. The obesity mice model was established through high-fat diet (HFD) induction. The mating assays evaluated the male infertility of obese mice. A mouse-derived spermatogonia (GC-1 spg) cell viability was detected using the Cell Counting Kit-8 assay. The reactive oxygen species (ROS) were assessed using flow cytometry. Furthermore, immunofluorescence, enzyme-linked immunosorbent assay, and western blotting were applied to measure the gene expressions. RESULTS: Blautia wexlerae was decreased and negatively correlated with interleukin-1 beta (IL-1ß) or IL-18 levels in infertile men with obesity. On the other hand, B. wexlerae improved the mating capability of obese male mice and suppressed oxidative stress and NLRP3 inflammasome via the activation of the acetate receptor. Furthermore, sodium acetate regulated oxidative stress and NLRP3 inflammasome via the activation of the acetate receptor in GC-1 spg cells in vitro. CONCLUSION: The administration of Blautia wexlerae improved obesity-associated male infertility and regulated oxidative stress and NLRP3 inflammasome activities. In general, its administration may be an effective strategy for the treatment of obesity-associated male infertility.
Subject(s)
Infertility, Male , Inflammasomes , NLR Family, Pyrin Domain-Containing 3 Protein , Obesity , Oxidative Stress , Male , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/genetics , Animals , Obesity/complications , Obesity/metabolism , Humans , Infertility, Male/etiology , Infertility, Male/metabolism , Inflammasomes/metabolism , Mice , Adult , Reactive Oxygen Species/metabolism , Disease Models, Animal , Diet, High-Fat , Interleukin-1beta/metabolism , Mice, Inbred C57BLABSTRACT
The MS2-PP7 two-color live-imaging system provides insights into the spatiotemporal dynamics of nascent transcripts at tagged loci. Here, we present a protocol to quantitatively measure the rate of RNA polymerase II elongation for each actively transcribing nucleus in living Drosophila embryos. The elongation rate is calculated by measuring the effective distance and the time elapsed between MS2 and PP7 trajectories. We describe steps for preparing embryo samples, performing live imaging, and measuring the elongation rate. For complete details on the use and execution of this protocol, please refer to Keller et al.1.
Subject(s)
Embryo, Nonmammalian , RNA Polymerase II , Animals , RNA Polymerase II/metabolism , RNA Polymerase II/genetics , Embryo, Nonmammalian/metabolism , Drosophila/embryology , Drosophila/metabolism , Drosophila melanogaster/embryology , Drosophila melanogaster/genetics , Drosophila melanogaster/metabolism , Drosophila Proteins/metabolism , Drosophila Proteins/geneticsABSTRACT
Stopping postoperative soft tissue adhesions is one of the most challenging clinical problems that needs to be addressed urgently to avoid secondary injury and pain to patients. Currently, membrane materials with anti-protein adsorption and antibacterial activity are recognized as an effective and promising anti-adhesion barrier to prevent postoperative adhesion and the recurrent adhesion after adhesiolysis. Herein, poly(amino acid) (PAA), which is structurally similar to collagen, is selected as the membrane base material to successfully synthesize PAA-5 membranes with excellent mechanical and degradation properties by in-situ melt polymerization and hot-melt film-forming technology. Subsequently, the co-deposition of polydopamine/polysulfobetaine methacrylate (PDA/PSBMA) coatings induced by CuSO4/H2O2on PAA-5 membranes results in the formation of PDC-5S and PDC-10S, which exhibit excellent hemocompatibility, protein antifouling properties, and cytocompatibility. Additionally, PDC-5S and PDC-10S demonstrated significant antibacterial activity againstEscherichia coliandStaphylococcus aureus, with an inhibition rate of more than 90%. As a result, this study sheds light on newly discovered PAA membranes with anti-protein adsorption and antibacterial activity can sever as one of the promising candidates for the prevention of postoperative peritoneum adhesions.
Subject(s)
Anti-Bacterial Agents , Escherichia coli , Hydrogen Peroxide , Indoles , Membranes, Artificial , Methacrylates , Polymers , Staphylococcus aureus , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Polymers/chemistry , Adsorption , Indoles/chemistry , Indoles/pharmacology , Methacrylates/chemistry , Escherichia coli/drug effects , Staphylococcus aureus/drug effects , Humans , Hydrogen Peroxide/chemistry , Animals , Materials Testing , Amino Acids/chemistry , Biofouling/prevention & control , Coated Materials, Biocompatible/chemistry , Coated Materials, Biocompatible/pharmacology , Betaine/chemistry , Betaine/analogs & derivatives , Tissue Adhesions/prevention & controlABSTRACT
In recent years, the development of environmentally friendly packaging materials using biodegradable polymers has emerged as a key challenge for scientists and consumers in response to resource depletion and environmental issues caused by plastic packaging materials. Starch and polyvinyl alcohol (PVA) are being recognized as excellent candidates for producing biodegradable food packaging films. Polymer blending has emerged as a practical approach to overcome the limitations of biopolymer films by developing films with unique properties and enhancing overall performance. This review briefly introduces the molecular structure and properties of starch and PVA, summarizes the common preparation methods and properties of starch/PVA blend films, and focuses on different strategies used to enhance starch/PVA blend films, including nanoparticles, plant extracts, and cross-linking agents. Additionally, this study summarizes the application of starch/PVA blend films as active and smart packaging in food preservation systems. This study demonstrates that starch and PVA blends have potential in manufacturing biodegradable food films with excellent properties due to their excellent compatibility and intermolecular interactions, and can be used as packaging films for a variety of foods to extend their shelf life.
Subject(s)
Food Packaging , Polyvinyl Alcohol , Starch , Polyvinyl Alcohol/chemistry , Food Packaging/methods , Starch/chemistry , Plastics/chemistryABSTRACT
In this paper, cascaded modal interferometers constructed by strongly-coupled seven-core fiber (SC-SCF) with different lengths are demonstrated for enhanced bending sensing based on Vernier effect. The free spectral range (FSR) of a single SC-SCF interferometer is determined by the length of SC-SCF. Two SC-SCF interferometers with different FSRs are cascaded, in which, one functions as the sensor while the other functions as the reference. The wavelength shift of the envelope of the output spectrum is much larger than that of a single SC-SCF interferometer due to the Vernier effect. Therefore, enhanced sensing can be achieved. Experimental results show that the bending sensitivity of the proposed sensor is improved from -2.20â nm/m-1 (single SC-SCF interferometer) to 42.32â nm/m-1 (cascaded SC-SCF interferometers). The temperature response of the sensor is also investigated. Our proposed cascaded SC-SCF sensor has advantages of high sensitivity, ease of fabrication, and low cost. It is attractive for high precision bending sensing applications.