Foraging hematophagous flies such as the stable fly, Stomoxys calcitrans, are shown or expected to sense multiple characteristics of visual host cues. These include relative intensity, spectral composition, and the angle and degree of polarization. Here, we investigated the role of each of these visual cue characteristics on stable fly attraction. In laboratory two-choice bioassays, we offered groups of female or male stable flies a choice between paired photostimuli that differed in their visual characteristics, recording the flies' landing responses on stimuli as the response criterion. Bioassay flies preferentially selected lower-intensity visual stimuli even when paired stimuli markedly differed in spectral composition and polarization characteristics (a high degree of horizontal or vertical polarization). When paired stimuli had identical relative intensity, flies failed to discriminate between the stimulus that presented ultraviolet, blue, green, and red wavebands and a corresponding paired stimulus lacking one of these wavebands. Our results support the hypothesis that foraging stable flies may respond to colour and polarization characteristics of visual stimuli as modulations of perceived intensity. Acquired knowledge on the mechanisms that underlie stable fly visual attraction may inform the design of vision-based traps so that they become optimally attractive to stable flies and other biting flies.

Foraging hematophagous flies such as the stable fly, Stomoxys calcitrans, are shown or expected to sense multiple characteristics of visual host cues. These include relative intensity, spectral composition, and the angle and degree of polarization. Here, we investigated the role of each of these visual cue characteristics on stable fly attraction. In laboratory two-choice bioassays, we offered groups of female or male stable flies a choice between paired photostimuli that differed in their visual characteristics, recording the flies' landing responses on stimuli as the response criterion. Bioassay flies preferentially selected lower-intensity visual stimuli even when paired stimuli markedly differed in spectral composition and polarization characteristics (a high degree of horizontal or vertical polarization). When paired stimuli had identical relative intensity, flies failed to discriminate between the stimulus that presented ultraviolet, blue, green, and red wavebands and a corresponding paired stimulus lacking one of these wavebands. Our results support the hypothesis that foraging stable flies may respond to colour and polarization characteristics of visual stimuli as modulations of perceived intensity. Acquired knowledge on the mechanisms that underlie stable fly visual attraction may inform the design of vision-based traps so that they become optimally attractive to stable flies and other biting flies.

Foraging hematophagous flies such as the stable fly, Stomoxys calcitrans, are shown or expected to sense multiple characteristics of visual host cues. These include relative intensity, spectral composition, and the angle and degree of polarization. Here, we investigated the role of each of these visual cue characteristics on stable fly attraction. In laboratory two-choice bioassays, we offered groups of female or male stable flies a choice between paired photostimuli that differed in their visual characteristics, recording the flies' landing responses on stimuli as the response criterion. Bioassay flies preferentially selected lower-intensity visual stimuli even when paired stimuli markedly differed in spectral composition and polarization characteristics (a high degree of horizontal or vertical polarization). When paired stimuli had identical relative intensity, flies failed to discriminate between the stimulus that presented ultraviolet, blue, green, and red wavebands and a corresponding paired stimulus lacking one of these wavebands. Our results support the hypothesis that foraging stable flies may respond to colour and polarization characteristics of visual stimuli as modulations of perceived intensity. Acquired knowledge on the mechanisms that underlie stable fly visual attraction may inform the design of vision-based traps so that they become optimally attractive to stable flies and other biting flies.

Eye swabs, bioassays, and even smart contact lenses can pick up biomarkers for various conditions

Eye swabs, bioassays, and even smart contact lenses can pick up biomarkers for various conditions

A collection of analytical tools for insect ecology research, currently covering age-stage, two-sex life table analysis and dose-response bioassays. The life table module supports fast batch processing of multi-group datasets, validates raw 'csv' data, computes cohort size, mean fecundity, age-stage survival rates, age-specific survival, age-specific fecundity, life expectancy, and derived population parameters (net reproductive rate, intrinsic and finite rates of increase, mean generation time), simultaneously generates age-stage survival curves for all groups, and exports all tabular results and plots to 'Excel' in a single run. The bioassay module estimates lethal concentrations by the traditional and the weighted (improved) linear regression methods and by probit analysis, with Abbott correction, 95% confidence intervals and chi-square goodness-of-fit tests; the lethal proportion can be set freely (e.g., 25%, 50%, 70% or 90%), so any LC value such as the LC25, LC70 or LC90 can be computed, not only the LC50. The regression plots and tables are exported to 'Excel'. Planned extensions include more insect ecology indicators, such as median lethal temperature/time (LT50) and thermal constants (effective accumulated temperature).

A collection of analytical tools for insect ecology research, currently covering age-stage, two-sex life table analysis and dose-response bioassays. The life table module supports fast batch processing of multi-group datasets, validates raw 'csv' data, computes cohort size, mean fecundity, age-stage survival rates, age-specific survival, age-specific fecundity, life expectancy, and derived population parameters (net reproductive rate, intrinsic and finite rates of increase, mean generation time), simultaneously generates age-stage survival curves for all groups, and exports all tabular results and plots to 'Excel' in a single run. The bioassay module estimates lethal concentrations by the traditional and the weighted (improved) linear regression methods and by probit analysis, with Abbott correction, 95% confidence intervals and chi-square goodness-of-fit tests; the lethal proportion can be set freely (e.g., 25%, 50%, 70% or 90%), so any LC value such as the LC25, LC70 or LC90 can be computed, not only the LC50. The regression plots and tables are exported to 'Excel'. Planned extensions include more insect ecology indicators, such as median lethal temperature/time (LT50) and thermal constants (effective accumulated temperature).

ABSTRACT Brucea javanica oil oral emulsion (BJOE) serves as an adjunctive therapeutic agent for glioblastoma multiforme (GBM); however, the inhibitory effects of its serum metabolites remain unexplored. In this study, ultrahigh performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UHPLC-Q-TOF-MS/MS) was employed to analyze serum metabolites in rats following BJOE administration. The inhibitory effects of the serum on GBM were assessed using U251 cell bioassays, and the relationship between serum metabolites and cellular inhibitory activity was examined. Six prototype components and six metabolites were identified in the serum, including linoleic acid, linoleic acid-M1, linoleic acid-M2, linoleic acid-M3, oleic acid, oleic acid-M1, oleic acid-M2, oleic acid-M3, sphingosine, palmitoleic acid, oleamide, and 1-stearoyl-rac-glycerol. Rat serum collected 2 h postdosing significantly inhibited U251 cell proliferation. Gray relationship analysis indicated that oleic acid, oleic acid-M1, linoleic acid, linoleic acid-M1, linoleic acid-M2, sphingosine, palmitoleic acid, oleamide, and 1-stearoyl-rac-glycerol were highly correlated with the inhibition rate of U251 cell proliferation, with oleic acid-M1 showing the highest correlation coefficient (0.9806). These findings suggest that BJOE and its metabolites may possess therapeutic potential against GBM, particularly in inhibiting glioma cell proliferation, with oleic acid and its metabolites likely playing a significant role.

Eye swabs, bioassays, and even smart contact lenses can pick up biomarkers for various conditions

Agriculture and Environmental Modelling (AEM) would like to warmly welcome Dr Junho Yoon as a new Subject Editor. Junho received his PhD from Seoul National University, South Korea, and is now a postd...

Using untargeted metabolomics and herbivore bioassays, the authors demonstrate that plants exhibit species-specific metabolic defense against multiple herbivore species. This process depends on both p...

Microfractionation is a prominent alternative for the discovery and characterization of bioactive natural products in complex extracts (e.g., plant, fungal, or microbial); however, the method faces limitations as it requires arduous scale-up for full ...

The rational design of fluorogenic amino acids for peptide-based fluorescence imaging is challenging. Now a strategy has been developed to prepare fluorogenic amino acids with adaptability across UV-t...

AbstractMultiplex electrochemiluminescence (ECL) bioassays in continuous flow require reliable target identification and event-resolved signal assignment within the same detection process. Here, we report a flow-through, micropore-confined bipolar electrochemiluminescence (BE-ECL) platform that uses structurally color-coded photonic amorphous conductive microbeads (PACMs) as mobile bipolar electrodes. The PACMs provide visually decodable identities and generate localized ECL at their poles, enabling simultaneous detection of CEA, CA125, and AFP. Micropore confinement concentrates the electric field in the detection region, and bead polarization further enhances local ECL generation under reduced driving voltages. A serpentine microfluidic injection module separates beads before detection, allowing decoded structural-color sequences to be matched to synchronous current perturbations and ECL peaks during continuous flow. The platform achieved sensitive, selective, and reproducible multiplex detection with low background. This work provides a practical strategy for encoded suspension-array ECL bioassays by integrating structural-color coding, micropore-confined BE-ECL, and flow-through bead analysis.

The synthesis of FgAAs has been restricted, so far, to the derivatization of environmentally sensitive scaffolds with amino acid moieties that enable integration into peptides and proteins. These approaches have rendered encodable amino acids (for example, CouA, ANAP and dansylalanine) to produce recombinant fluorescent proteins31,32,33, tetrahydroquinoline rotor fluorogenic d-amino acids for imaging transpeptidation reactions in bacterial cells20 or small nitrobenzodiazoles for super-resolution microscopy34. While useful, the broad application of these amino acids is hampered by the optical properties of fluorogenic cores. For instance, CouA, ANAP and dansylalanine display short excitation wavelengths (that is, <400 nm) that overlap with cellular autofluorescence, whereas tetrahydroquinolines and nitrobenzodiazoles exhibit moderate-to-low extinction coefficients (that is, in the 103–104 M−1 cm−1 range). We envisaged that the preparation of FgAAs by direct conversion of fluorescent structures would expand not only the chemical diversity of the FgAA toolbox but also their optical properties and range of applications in fluorescence-based imaging. Our group and others have reported the fine-tuning and optical modulation of organic fluorophores using a wide range of intramolecular quenching mechanisms35,36,37,38,39,40. Among others, these include the incorporation of metal ion chelators (for example, Cu2+ and Sn2+) to generate ion-sensitive fluorophores41,42, spirocyclization mechanisms to modulate pH sensitivity and...

Nature Chemistry, Published online: 26 August 2026; doi:10.1038/s41557-026-02228-0The rational design of fluorogenic amino acids for peptide-based fluorescence imaging is challenging. Now a strategy has been developed to prepare fluorogenic amino acids with adaptability across UV-to-NIR fluorophore scaffolds. The integration of these amino acids into solid-phase peptide synthesis generates fluorogenic peptide probes for real-time microscopy and flow cytometry in live cells.

The widespread transmission of mosquito-borne diseases such as dengue, chikungunya, Zika, and yellow fever by Aedes albopictus necessitates environmentally sustainable vector control solutions. This study developed and characterized a citral-based nanoemulsion using Tween 80 via low-energy emulsification, aiming to enhance larvicidal efficacy and environmental safety. Larvicidal bioassays against third instar A. albopictus revealed significantly higher potency for citral nanoemulsion (LC(50):...

Rhipicephalus microplus is a cattle ectoparasite responsible for economic losses in livestock systems. The present study aimed to evaluate the essential oil (EO) of Piper hemmendorffii and its major constituent, limonene, for their activity against R. microplus larvae. The EO of P. hemmendorffii and its major compound, limonene, were evaluated against pyrethroid-resistant R. microplus larvae using larval immersion bioassays, biochemical analyses of detoxification enzymes and acetylcholinesterase, and scanning electron microscopy (SEM). The EO showed higher larvicidal potency (LC50 = 10.46 mg/mL; 95% CI: 9.86&ndash;11.09) compared to limonene (LC50 = 31.62 mg/mL; 95% CI: 30.86&ndash;32.40). Piper hemmendorffii EO affected the following classes of enzymes investigated: &alpha;-Esterase (&alpha;-EST) activity increased at LC25 and LC50, reaching its highest level at LC50, whereas &beta;-esterase (&beta;-EST) activity increased only at LC25. Cytochrome P450 (CYP450)-associated heme content activity showed a significant increase exclusively at LC50, suggesting a response of the surviving larvae to EO exposure, although this increase does not by itself demonstrate the activation of detoxification pathways. In contrast, limonene did not significantly affect the activity of the three evaluated enzymes. The inhibition of AChE by the EO suggests a possible effect on the cholinergic system, which may be associated with neurotoxic activity, whereas limonene had no significant effect. The absence of detectable ultrastructural changes by SEM suggests that treatment with either EO or limonene did not induce evident external morphological damage to the larval cuticle under the evaluated conditions. EO toxicity seems to be associated with changes in detoxification enzyme and AChE activities, suggesting the involvement of these biochemical pathways in larval response.