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1.
Food Chem X ; 23: 101636, 2024 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-39113734

RESUMEN

Emulsion gels mimic the rheological properties of solid and semi-solid fats, offering a viable solution to replace conventional fats in low-fat food formulations. In this study, gel emulsions stabilized with stigmasterol (ST) and polyglycerol polyricinoleate (PGPR) complexes were prepared. Initially, we examined the effect of the ST/PGPR complex on the mechanism of gel emulsion stabilization. Our findings revealed that the gel emulsion formulated with 3% PGPR and ST exhibited a robust structure, effectively stabilizing the entire system and ensuring uniform distribution, and increasing ST concentration led to greater stability of the gel emulsion system. Stability assessments demonstrated that gel emulsions containing 3% PGPR and varying ST concentrations exhibited remarkable thermal stability and effectively delayed oil oxidation. These results underscore the high stability of gel emulsions stabilized with the ST/PGPR complex, highlighting their potential as a margarine substitute.

2.
Front Pharmacol ; 15: 1361733, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39130645

RESUMEN

Introduction: Cytotoxic cerebral edema is a serious complication associated with cerebral ischemic stroke and is widely treated using the hypertonic dehydrant. Here, we propose, for the first time, the decrease of intracellular osmosis as a treatment strategy for alleviating cytotoxic cerebral edema. Methods: We established a fluorescence resonance energy transfer-based intermediate filament tension probe for the study and in situ evaluation of osmotic gradients, which were examined in real-time in living cells from primary cultures as well as cell lines. The MCAO rat model was used to confirm our therapy of cerebral edema. Results: Depolymerization of microfilaments/microtubules and the production of NLRP3 inflammasome resulted in an abundance of protein nanoparticles (PNs) in the glutamate-induced swelling of astrocytes. PNs induced changes in membrane potential and intracellular second messengers, thereby contributing to hyper-osmosis and the resultant astrocyte swelling via the activation of voltage-dependent nonselective ion channels. Therefore, multiple inhibitors of PNs, sodium and chloride ion channels were screened as compound combinations, based on a decrease in cell osmosis and astrocyte swelling, which was followed by further confirmation of the effectiveness of the compound combination against alleviated cerebral edema after ischemia. Discussion: The present study proposes new pathological mechanisms underlying "electrophysiology-biochemical signal-osmotic tension," which are responsible for cascade regulation in cerebral edema. It also explores various compound combinations as a potential treatment strategy for cerebral edema, which act by multi-targeting intracellular PNs and voltage-dependent nonselective ion flux to reduce astrocyte osmosis.

3.
Pharmacol Res ; 207: 107341, 2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-39134188

RESUMEN

Drug conjugates are obtained from tumor-located vectors connected to cytotoxic agents via linkers, which are designed to deliver hyper-toxic payloads directly to targeted cancer cells. These drug conjugates include antibody-drug conjugates (ADCs), peptide-drug conjugates (PDCs), small molecule-drug conjugates (SMDCs), nucleic acid aptamer-drug conjugates (ApDCs), and virus-like drug conjugate (VDCs), which show great therapeutic value in the clinic. Drug conjugates consist of a targeting carrier, a linker, and a payload. Payloads are key therapy components. Cytotoxic molecules and their derivatives derived from natural products are commonly used in the payload portion of conjugates. The ideal payload should have sufficient toxicity, stability, coupling sites, and the ability to be released under specific conditions to kill tumor cells. Microtubule protein inhibitors, DNA damage agents, and RNA inhibitors are common cytotoxic molecules. Among these conjugates, cytotoxic molecules of natural origin are summarized based on their mechanism of action, conformational relationships, and the discovery of new derivatives. This paper also mentions some cytotoxic molecules that have the potential to be payloads. It also summarizes the latest technologies and novel conjugates developed in recent years to overcome the shortcomings of ADCs, PDCs, SMDCs, ApDCs, and VDCs. In addition, this paper summarizes the clinical trials conducted on conjugates of these cytotoxic molecules over the last five years. It provides a reference for designing and developing safer and more efficient conjugates.

4.
Foods ; 13(15)2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39123505

RESUMEN

The presence of cracks reduces egg quality and safety, and can easily cause food safety hazards to consumers. Machine vision-based methods for cracked egg detection have achieved significant success on in-domain egg data. However, the performance of deep learning models usually decreases under practical industrial scenarios, such as the different egg varieties, origins, and environmental changes. Existing researches that rely on improving network structures or increasing training data volumes cannot effectively solve the problem of model performance decline on unknown egg testing data in practical egg production. To address these challenges, a novel and robust detection method is proposed to extract max domain-invariant features to enhance the model performance on unknown test egg data. Firstly, multi-domain egg data are built on different egg origins and acquisition devices. Then, a multi-domain trained strategy is established by using Maximum Mean Discrepancy with Normalized Squared Feature Estimation (NSFE-MMD) to obtain the optimal matching egg training domain. With the NSFE-MMD method, the original deep learning model can be applied without network structure improvements, which reduces the extremely complex tuning process and hyperparameter adjustments. Finally, robust cracked egg detection experiments are carried out on several unknown testing egg domains. The YOLOV5 (You Only Look Once v5) model trained by the proposed multi-domain training method with NSFE-MMD has a detection mAP of 86.6% on the unknown test Domain 4, and the YOLOV8 (You Only Look Once v8) model has a detection mAP of 88.8% on Domain 4, which is an increase of 8% and 4.4% compared to the best performance of models trained on a single domain, and an increase of 4.7% and 3.7% compared to models trained on all domains. In addition, the YOLOV5 model trained by the proposed multi-domain training method has a detection mAP of 87.9% on egg data of the unknown testing Domain 5. The experimental results demonstrate the robustness and effectiveness of the proposed multi-domain training method, which can be more suitable for the large quantity and variety of egg detection production.

5.
Psychol Res Behav Manag ; 17: 2819-2834, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39099587

RESUMEN

Purpose: Self-deception refers to an individual holding inflated beliefs about their abilities, plays a crucial role in human behavior and decision-making. Individuals may inflate their abilities when subject to comparisons with others. This study examined the impact of social comparison on self-deception through the implementation of two behavioral experiments. Methods: In Experiment 1, we recruited a sample of 152 undergraduate students. Participants were falsely informed that they performed better (downward comparison) and worse (upward comparison) than average on a game. Subsequently, their level of self-deception was assessed by asking them to predict their performance in a future game, with more inflated predictions indicating greater self-deception. In Experiment 2, we gathered 126 undergraduate students to broaden the current study. This experiment examined the combined effects of comparison direction and comparison gap on self-deceptive behavior. Results: The findings showed that self-deception was more common in circumstances of upward comparison than in downward comparison or no comparison (Experiment 1). Furthermore, Individuals were more inclined to participate in self-deception when encountering a notable performance gap relative to others, particularly in scenarios involving upward social comparison (Experiment 2). Conclusion: The findings suggested that when confronted with threatening social comparative information, people tended to use self-deception to protect themselves. Members of the large gap group experienced strong feelings of unfairness and negative emotions, which led to self-protective behaviors and a greater likelihood of self-deception.

6.
Biomed Eng Online ; 23(1): 79, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39113053

RESUMEN

OBJECTIVES: The abnormal anatomical alterations of blood vessels during DSA angiography in patients with hematological disorders were retrospectively examined, and the influencing factors of short-term (≤ 6 months) recurrent hemoptysis were statistically analyzed, and the consistency between admission diagnosis and intraoperative diagnosis was evaluated. METHODS: The intraoperative angiography data of patients who underwent selective bronchial artery embolization for hemoptysis in our hospital from January 2022 to December 2022 were reviewed. They were divided into the observation group and the control group based on whether there was recurrent hemoptysis. The Logistic regression model and forest map were employed to analyze the factors influencing the recurrence rate. RESULTS: A total of 104 patients were encompassed in this study (12 cases of tuberculosis, 35 cases of infection, 4 cases of lung cancer, 8 cases of bronchiectasis, 22 cases of arteriovenous fistula, 16 cases of aneurysm, and 7 cases of pulmonary hypertension). The coincidence rate of preoperative and intraoperative diagnoses was 73.1%. Pulmonary arteriovenous fistula and aneurysm were the predominant types of diseases that were misdiagnosed. The short-term recurrence rate was 16.3%, mainly attributed to the reopening of responsible vessels related to embolization, angiography leakage, and leaky embolization of specific types of vessels. The recurrence rate of only patients with arteriovenous fistula and aneurysm accounted for 47% of the total recurrence rate. The right bronchial artery, right internal thoracic artery, right thyroid neck trunk, and age were the independent factors influencing the recurrence of hemoptysis (p < 0.05). CONCLUSIONS: The main reason for angiographic leakage and embolization leakage in cases of hemoptysis is the lack of understanding of the anatomic variations of the vessels responsible. Careful examination of the specific types and locations of the vessels is the principal approach to reducing secondary operations.


Asunto(s)
Angiografía , Embolización Terapéutica , Hemoptisis , Recurrencia , Humanos , Hemoptisis/diagnóstico por imagen , Hemoptisis/terapia , Masculino , Femenino , Persona de Mediana Edad , Adulto , Anciano , Estudios Retrospectivos , Factores de Tiempo
7.
ACS Nano ; 18(33): 22095-22103, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39114966

RESUMEN

Designing a high-performing iridium (Ir) single-atom catalyst is desired for acidic water electrolysis, which shows enormous potential given its high catalytic activity toward acidic oxygen evolution reaction (OER) with minimum usage of precious Ir metal. However, it still remains a substantial challenge to stabilize the Ir single atoms during the OER operation without sacrificing the activity. Here, we report a high-performing OER catalyst by immobilizing Ir single atoms on a polyimide support, which exhibits a high mass activity on a carbon paper electrode while simultaneously achieving outstanding stability with negligible decay for 360 h. The resulting electrode (denoted as Ir1-PI@CP) reaches a 49.7-fold improvement in mass activity compared to the counterpart electrode prepared without polyimide support. Both our experimental and theoretical results suggest that, owing to the strong metal-support interactions, the polyimide support can enhance the Ir 5d states of Ir single atoms in Ir1-PI@CP, which can tailor the adsorption energies of intermediates and decrease the thermodynamic barrier at the rate-determining step of the OER, but also facilitate the proton-electron-transfer process and improve the reaction kinetics. This work offers an alternative avenue for developing single-atom catalysts with superior activity and durability toward various catalytic systems and beyond.

8.
Nanotechnology ; 35(43)2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39105490

RESUMEN

Ammonia (NH3) is a versatile and important compound with a wide range of uses, which is currently produced through the demanding Haber-Bosch process. Electrocatalytic nitrate reduction into ammonia (NRA) has recently emerged as a sustainable approach for NH3synthesis under ambient conditions. However, the NRA catalysis is a complex multistep electrochemical process with competitive hydrogen evolution reaction that usually results in poor selectivity and low yield rate for NH3synthesis. With maximum atom utilization and well-defined catalytic sites, single atom catalysts (SACs) display high activity, selectivity and stability toward various catalytic reactions. Very recently, a number of SACs have been developed as promising NRA electrocatalysts, but systematical discussion about the key factors that affect their NRA performance is not yet to be summarized to date. This review focuses on the latest breakthroughs of SACs toward NRA catalysis, including catalyst preparation, catalyst characterization and theoretical insights. Moreover, the challenges and opportunities for improving the NRA performance of SACs are discussed, with an aim to achieve further advancement in developing high-performance SACs for efficient NH3synthesis.

9.
Cytometry A ; 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39132928

RESUMEN

Single-cell sorting (index sorting) is a widely used method to isolate one cell at a time using fluorescence-activated cell sorting (FACS) for downstream applications such as single-cell sequencing or single-cell expansion. Despite widespread use, few assays are available to evaluate the proteomic features of the sorted single cell and further confirm the accuracy of single-cell sorting. With this caveat, we developed a novel assay to confirm the protein expression of sorted single cells by co-staining cells with the same marker using both antibody-derived tags (ADTs) and fluorescent antibodies. After single-cell sorting, we amplified the oligo of the ADT reagent as a surrogate signal for the protein expression using multiplex TaqMan™ qPCR on sorted cells. This assay is not only useful for confirming the identity of a sorted single cell but also an efficient method to profile proteomic features at the single-cell level. Finally, we applied this assay to characterize protein expression on whole cell lysate. Because of the sensitivity of the TaqMan™ qPCR, we can detect protein expression from a small number of cells. In summary, the ADT-based qPCR assay developed here can be utilized to confirm single-cell sorting accuracy and characterizing protein expression on both single cells and whole cell lysate.

11.
Nature ; 632(8024): 301-306, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39048825

RESUMEN

Molecule-based selective contacts have become a crucial component to ensure high-efficiency inverted perovskite solar cells1-5. These molecules always consist of a conjugated core with heteroatom substitution to render the desirable carrier-transport capability6-9. So far, the design of successful conjugation cores has been limited to two N-substituted π-conjugated structures, carbazole and triphenylamine, with molecular optimization evolving around their derivatives2,5,10-12. However, further improvement of the device longevity has been hampered by the concomitant limitations of the molecular stability induced by such heteroatom-substituted structures13,14. A more robust molecular contact without sacrificing the electronic properties is in urgent demand, but remains a challenge. Here we report a peri-fused polyaromatic core structure without heteroatom substitution that yields superior carrier transport and selectivity over conventional heteroatom-substituted core structures. This core structure produced a relatively chemically inert and structurally rigid molecular contact, which considerably improved the performance of perovskite solar cells in terms of both efficiency and durability. The champion device showed an efficiency up to 26.1% with greatly improved longevity under different accelerated-ageing tests.

12.
Heliyon ; 10(12): e33298, 2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-39022052

RESUMEN

To investigate the spatial and temporal patterns of environmental factors influencing the activity of purse seine tuna fishing vessels, data on fishing efforts of purse seine tuna fleets and environmental factors in the Western and Central Pacific Ocean (WCPO) from 2015 to 2020 were utilized to develop a geographically weighted regression (GWR) model. The results showed that fishing activity was primarily concentrated in the area between 140°E and 175°W, and between 10°S and 5°N. The GWR model showed excellent fitting performance and was suitable for correlation analysis. The environmental factors had a significant spatially heterogeneous effect on the fishing activity of purse seine tuna fishing vessels. The sea surface temperature, primary productivity at 200 m depth, and dissolved oxygen below the surface had the greatest spatially heterogeneous effect and are important environmental variables influencing the activity of purse seine tuna vessels in the WCPO. This study provides new methods for exploring the spatial distribution of fishing vessel activity to support science-based conservation and management.

13.
Artículo en Inglés | MEDLINE | ID: mdl-39027983

RESUMEN

Panax notoginseng has the effect of stimulating circulation to end stasis. Our study was designed to evaluate the anti-thrombotic effect of protoparaxotriol saponins (PTS) from Panax notoginseng and the involved mechanisms. A thrombosis model was constructed, and the anti-thrombotic activity of PTS was determined by erythrocyte staining, heart rate, and blood flow velocity. In addition, quantitative real-time polymerase chain reaction (qPCR) was used to identify changes in the expression of genes related to coagulation, inflammation, and apoptosis. PTS alleviated arachidonic acid (AA)-induced caudal vein thrombosis, restored blood flow, and increased the area of cardiac erythrocyte staining, heart rate and blood flow velocity. It reduced the ponatinib-induced cerebral thrombus area and decreased the intensity of erythrocyte staining. The qPCR data showed that the anti-thrombotic effect of PTS was mediated by suppression of genes related to coagulation, inflammation and apoptosis, and also involved inhibition of NF-κB and PI3K/Akt pathways.

14.
Sci Data ; 11(1): 799, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39025902

RESUMEN

Callosobruchus maculatus is one of the most competitive stored grain pests, which causes a great loss to agricultural economy. However, due to an inadequacy of high-quality reference genome, the molecular mechanisms for olfactory and hypoxic adaptations to stored environments are unknown and require to be revealed urgently, which will contribute to the detection and prevention of the invasive pests C. maculatus. Here, we presented a high-quality chromosome-level genome of C. maculatus based on Illumina, Nanopore and Hi-C sequencing data. The total size was 1.2 Gb, and 65.17% (797.47 Mb) of it was identified to be repeat sequences. Among assembled chromosomes, chromosome 10 was considered the X chromosome according to the evidence of reads coverage and homologous genes among species. The current version of high-quality genome provides preferable data resources for the adaptive evolution research of C. maculatus.


Asunto(s)
Escarabajos , Genoma de los Insectos , Animales , Escarabajos/genética
15.
Prenat Diagn ; 2024 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-39072792

RESUMEN

OBJECTIVE: Currently, the most commonly used methods for linkage analysis of pre-implantation genetic testing for monogenic disorders (PGT-M) are next generation sequencing (NGS) and SNP array. We aim to investigate whether the application efficacy of Asian screening array (ASA) in PGT-M preclinical workup for the Chinese population is superior to NGS based single nucleotide polymorphism (SNP) panels. METHODS: We conducted a retrospective analysis by reviewing 294 couples from a single center over the past 4 years and compared the detection results between NGS-based SNP panels and ASA. Using the numbers of informative SNPs upstream and downstream flanking of variants, we assessed the detection efficiency of both methods in monogenic diseases, chromosomal microdeletion syndrome and males with de novo variants, among other scenarios. RESULTS: Results indicate that ASA offers a greater number of informative SNPs compared with NGS-based SNP panels. Additionally, data analysis for ASA is generally more straightforward and may require less computational resources. While ASA can address most PGT-M challenges, we have also identified certain genes in previous tests that are not suitable for PGT-M using ASA. CONCLUSION: The application of ASA in PGT-M preclinical workup for Chinese populations has good practical value as it can perform linkage analysis for most genetic variants. However, for certain variants, NGS or other testing methods, such as mutated allele revealed by sequencing with aneuploidy and linkage analysis (MARSALA), may still be necessary for completion.

16.
Int J Nanomedicine ; 19: 6981-6997, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39005961

RESUMEN

Background: Enterococcus faecalis (E. faecalis) is one of the main pathogens responsible for refractory root canal infections in the teeth and shows resistance against various antibacterial managements. Effective control of E. faecalis infection is a prerequisite for successful treatment of refractory apical periodontitis. This study aimed to analyze the antibacterial activity and mechanisms of Au@Ag nanoparticles (NPs) combined with photothermal therapy (PTT) against the original and Ag+-resistant E. faecalis. Methods: Au@AgNPs with optimal shell thicknesses were synthesized and characterized. The antibacterial activity of Au@AgNPs with PTT against the original or Ag+-resistant E. faecalis was evaluated, and the antibiofilm activity was tested on E. faecalis biofilm on the dentin of teeth. The potential antibacterial mechanisms of Au@AgNPs combined with PTT against E. faecalis have also been studied. Moreover, its influence on dentin microhardness and cytotoxicity was assessed. Results: This study revealed that Au@AgNPs combined with PTT showed enhanced antibacterial and antibiofilm effects, no negative effects on dentin microhardness, and low cytotoxicity toward human periodontal ligament cells (hPDLCs). Moreover, Au@AgNPs combined with PTT effectively inhibited the growth of Ag+-resistant E. faecalis. Its antibacterial effects may be exerted through the release of silver ions (Ag+), destruction of the cell membrane, production of reactive oxygen species (ROS) and inhibition of adenosine triphosphate (ATP) production. Hyperthermia generated by Au@AgNPs with PTT reduced membrane fluidity and enhanced Ag+ sensitivity by downregulating fabF expression. The upregulated expression of heat shock genes demonstrated that the Ag+ released from Au@AgNPs compromised the heat adaptation of E. faecalis. Conclusion: PTT significantly enhanced Ag+ sensitivity of the original and Ag+-resistant E. faecalis. Au@AgNPs combined with PTT may have the potential to be developed as a new antibacterial agent to control E. faecalis infections in teeth.


Asunto(s)
Antibacterianos , Biopelículas , Dentina , Enterococcus faecalis , Oro , Nanopartículas del Metal , Plata , Plata/química , Plata/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Enterococcus faecalis/efectos de los fármacos , Humanos , Oro/química , Oro/farmacología , Nanopartículas del Metal/química , Dentina/química , Dentina/efectos de los fármacos , Biopelículas/efectos de los fármacos , Terapia Fototérmica/métodos , Pruebas de Sensibilidad Microbiana , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Rayos Infrarrojos , Especies Reactivas de Oxígeno/metabolismo
17.
Eur J Intern Med ; 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-39048339
18.
Front Immunol ; 15: 1429405, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39055718

RESUMEN

The treatment of primary Sjögren's syndrome (pSS) coexisting with neuromyelitis optica spectrum disorder (NMOSD) using protein-A immunoadsorption combined with immunosuppressive therapy has rarely been reported. Herein, we present the case of a 35-year-old female diagnosed with pSS concomitant with NMOSD (pSS-NMOSD) who demonstrated a positive response to protein-A immunoadsorption after failing to respond to therapy comprising high-dose intravenous methylprednisolone (IVMP) and intravenous immunoglobulin (IVIG). Within one week of receiving three sessions of immunoadsorption combined with immunosuppressive treatment, the patient's clinical symptoms (blurred vision, paraparesis, and dysfunctional proprioception) significantly improved. Additionally, a rapid decrease in the circulating levels of Aquaporin-4 immunoglobulin G antibodies (AQP4-IgG), immunoglobulin (Ig) A, IgG, IgM, erythrocyte sedimentation rate (ESR), and rheumatoid factor (RF) were observed. Magnetic resonance imaging (MRI) further revealed a significant reduction in the lesions associated with longitudinal extensive transverse myelitis. During the follow-up period, prednisolone was gradually tapered to a maintenance dose of 5-10 mg/day, whereas mycophenolate mofetil (MMF) was maintained at 1.0-1.5 g/day. The patient's condition has remained stable for four years, with no signs of recurrence or progression observed on imaging examination. Therefore, this case suggests that protein A immunoadsorption may represent a potentially effective therapeutic option for patients with pSS-NMOSD who are refractory to conventional treatments.


Asunto(s)
Inmunosupresores , Neuromielitis Óptica , Síndrome de Sjögren , Humanos , Femenino , Neuromielitis Óptica/terapia , Neuromielitis Óptica/inmunología , Neuromielitis Óptica/diagnóstico , Síndrome de Sjögren/terapia , Síndrome de Sjögren/inmunología , Síndrome de Sjögren/complicaciones , Síndrome de Sjögren/diagnóstico , Adulto , Inmunosupresores/uso terapéutico , Proteína Estafilocócica A/inmunología , Autoanticuerpos/sangre , Autoanticuerpos/inmunología , Resultado del Tratamiento , Técnicas de Inmunoadsorción , Acuaporina 4/inmunología , Terapia Combinada
19.
Insects ; 15(7)2024 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-39057265

RESUMEN

In this study, the morphology and ultrastructure of the compound eye of Asi. xanthospilota were examined by using scanning electron microscopy (SEM), transmission electron microscopy (TEM), micro-computed tomography (µCT), and 3D reconstruction. Spectral sensitivity was investigated by electroretinogram (ERG) tests and phototropism experiments. The compound eye of Asi. xanthospilota is of the apposition type, consisting of 611.00 ± 17.53 ommatidia in males and 634.8 0 ± 24.73 ommatidia in females. Each ommatidium is composed of a subplano-convex cornea, an acone consisting of four cone cells, eight retinular cells along with the rhabdom, two primary pigment cells, and about 23 secondary pigment cells. The open type of rhabdom in Asi. xanthospilota consists of six peripheral rhabdomeres contributed by the six peripheral retinular cells (R1~R6) and two distally attached rhabdomeric segments generated solely by R7, while R8 do not contribute to the rhabdom. The orientation of microvilli indicates that Asi. xanthospilota is unlikely to be a polarization-sensitive species. ERG testing showed that both males and females reacted to stimuli from red, yellow, green, blue, and ultraviolet light. Both males and females exhibited strong responses to blue and green light but weak responses to red light. The phototropism experiments showed that both males and females exhibited positive phototaxis to all five lights, with blue light significantly stronger than the others.

20.
Rev Sci Instrum ; 95(7)2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-39041905

RESUMEN

Interfacial bonding between aramid fibers and epoxy resin is crucial for the mechanical properties of fiber-reinforced epoxy composites. Interfacial stress transfer between resin and fibers bridges microscopic and macroscopic properties. Using micro-Raman spectroscopy for in situ stress measurement offers insights into interface bonding through assessment of interfacial stress transfer characteristics. This study measures stress distribution on loaded microdroplet sample surfaces, analyzes stress transfer at the interface, and proposes an evaluation method using finite element analysis (FEA). The results show that interfacial stress along the fiber decreases from the droplet's edge to center, indicating stress transfer between the fiber and matrix, as evidenced by the stress-dependent Raman shift of aramid fiber. The interface modulus (Eif), derived from the FEA model, effectively reflects interface bonding, with droplet shape influence removed in evaluations. The agreement between the proposed method and the transverse fiber bundle test confirms its applicability. The method offers a direct, non-destructive, and shape-independent way to evaluate the interface of aramid/epoxy composites.

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